uuid
stringlengths 36
36
| chunk_index
int64 0
24
| text
stringlengths 1
1.82k
⌀ |
|---|---|---|
fe3b40d3-384d-49ac-bef2-24d4cb237469
| 0 |
Effects of training on biochemical values in standardbred horses. Effects of training at a regular, fixed, standard exercise load on venous lactic acid, mixed venous and arterial blood gases and pH, and serum muscle enzymes were determined on previously unconditioned, healthy, adult, Standardbred horses. Arterial and mixed venous blood gases, pH, and serum muscle enzymes did not change in a consistent manner during training. Venous lactic acid concentrations did increase significantly with training and may be of value for the biochemical evaluation of fitness in horses.
|
4864d466-8e4e-4557-9537-bd8108b3eed4
| 0 |
Acid-base values of standardbred horses recovering from strenuous exercise. Blood gases, lactic acid concentrations, and pH were measured in arterial and mixed venous blood in moderately conditioned Standardbred horses after a standardized exercise load of 1.6 km in 2 minutes, 40 seconds. Samples were obtained at rest, immediately after exercise, and at 3, 6, 15, 30, and 60 minutes after exercise.
|
4864d466-8e4e-4557-9537-bd8108b3eed4
| 1 |
Arterial oxygen tension and mixed venous oxygen tension increased after exercise, reaching peak values at 6 minutes. Arterial oxygen tension returned to the resting (preexercise) value by 15 minutes, and mixed venous oxygen tension by 30 minutes. Arterial carbon dioxide tension decreased immediately after exercise, reaching its lowest value at 6 minutes, and returned to resting value by 30 minutes.
|
4864d466-8e4e-4557-9537-bd8108b3eed4
| 2 |
Mixed venous carbon dioxide tension reached its highest value immediately after exercise, then decreased to less than the resting value, reaching its lowest value by 15 minutes, and returned to normal by 60 minutes. Lactic acid concentration increased immediately after exercise, reaching its highest value at 6 minutes, and returned toward normal by 60 minutes.
|
4864d466-8e4e-4557-9537-bd8108b3eed4
| 3 |
Arterial pH decreased immediately after exercise, reaching its lowest value at 6 minutes, and returned to normal by 60 minutes. Mixed venous pH reached its lowest value immediately after exercise, then began to increase, and returned to normal by 60 minutes. The decrease in mixed venous pH was more pronounced than that in arterial blood since, in addition to the increase in lartic acid, there was a considerable increase in mixed venous carbon dioxide tension.
|
33e1508e-9ae4-4a14-b20d-72f3ae4e54ff
| 0 |
[Metabolic acidosis and intravenous injections of fat emulsions (role of phospholipids. Experimental study)]. In explanation of metabolic acidosis during parenteral nutrition, the authors considered the supply of H+ ions by fat emulsion, containing phospholipids of egg or soy. During intravenous infusions of 24 grams of lecithins to two healthy subjects, they observed an increased output H+ ions in urine, about 74,05 and 75,88 mEq, and a metabolic acidosis of the plasma.
|
33e1508e-9ae4-4a14-b20d-72f3ae4e54ff
| 1 |
The theorically forcasted supply of production was 74,6 mEq. Indeed the metabolism of phospholipids supplies phosphoric ions (PO4H3), giving H+ ions at pH 7,40. The most used fat emulsions are able to give between 37 (intralipid 10%) and 61 (lipihysan 15%) mEq of H+ ions/liter.
|
abbb0a12-8782-4dc9-8a0a-5101df6976c8
| 0 |
Identification of immunoglobulins associated with complement fixation, agglutination, and low pH buffered antigen tests for brucellosis. Serums from infected cattle, cattle with persistent postvaccinal antibody, and serologically "positive" noninfected cattle were fractionated into major immunoglobulin classes by diethylaminoethyl (DEAE)-cellulose chromatography and by sucrose density gradient centrifugation.
|
abbb0a12-8782-4dc9-8a0a-5101df6976c8
| 1 |
Each fraction was assayed for anti-Brucella activity by standard tube-agglutination test (STT), buffered tube-agglutination test (BTT), and complement-fixation test (CF). In the serums from experimentally infected cattle, anti-Brucella antibody could be found by all tests in 6 DEAE fractions and in slow, fast, and sediment regions of the density gradient.
|
abbb0a12-8782-4dc9-8a0a-5101df6976c8
| 2 |
Serums from cattle with persistent postvaccinal titers had STT activity in all 6 DEAE fractions, BTT activity in 5 fractions, and CF activity in only 1 fraction. The STT and BTT activities were found in the slow and the sediment regions of the gradient, whereas the CF activity was found only in the slow region.
|
abbb0a12-8782-4dc9-8a0a-5101df6976c8
| 3 |
Serums from a chronically infected animal had STT and BTT activities in 2 DEAE fractions and CF activity in only 1. The STT, BTT, and CF activities were found in the slow and the sediment regions of the gradient. The principal antibody in serums from noninfected cattle was immunoglobulin M, which had all of the CF activity and most of the STT and BTT activities.
|
abbb0a12-8782-4dc9-8a0a-5101df6976c8
| 4 |
Low levels of STT and BTT activities were found in 3 other DEAE fractions. Only STT and BTT activities were found in the fast and the sediment regions of the gradient.
|
786fe0cf-3c24-4a94-ad55-f059a9439d4b
| 0 |
Theoretic significance of pH dependence of narcotics and narcotic antagonists in clinical anesthesia. Determination of the effect of pH and temperature on pKa partition, and drug distribution coefficients in a series of common narcotics and their antagonists has shown that within the range of blood pH (7.1 to 7.7
|
786fe0cf-3c24-4a94-ad55-f059a9439d4b
| 1 |
) encountered in the practice of anesthesiology, marked differences of distribution of the drugs between a model lipid (octanol) and water can occur. When these data are considered in the light of clinical experience with narcotics used in patients undergoing or recovering from surgical procedures, a correlation between the depth and duration of narcosis or the efficacy of narcotic antidotes and ventilatory status is seen.
|
786fe0cf-3c24-4a94-ad55-f059a9439d4b
| 2 |
This correlation can be explained in part if the influence of blood pH on the probable CNS/blood distribution of a given drug is taken into consideration. Support is given to this proposal by representative studies in the literature. The very different drug distribution coefficients of two closely related narcotic antagonists, naloxone and naltrexone, correctly predicted the faster onset and shorter duration of the former, which was confirmed by reported clinical observations.
|
0ccd45c8-562f-4322-8b35-29fdaa30dc45
| 0 |
"Aspiration disease". Aspiration disease, a term used to define both an acute and chronic form of a disease entity, is described. Etiological factors, pathophysiology and therapy are discussed with emphasis on aspiration of gastric juice. A brief mention of a small clinical experience is included.
|
e5f63806-a98f-420c-a50a-88205aa5ad9c
| 0 |
Plasmid-mediated penicillin beta-lactamases in Pseudomonas aeruginosa. A penicillin beta-lactamase (PCase) was extracted from Pseudomonas aeruginosa Rms139(+) and purified by means of column chromatography. The isoelectric point of Rms139 PCase was 5.7 and its molecular weight was 22,500 +/- 1,000. The optimal pH for the hydrolysis of benzylpenicillin was 7.0
|
e5f63806-a98f-420c-a50a-88205aa5ad9c
| 1 |
to 7.5 and the optimal temperature was 45 C, with the PCase also showing high activity against carbenicillin. It is concluded that this enzyme is a new type of penicillin beta-lactamase different from the type I, II, or III R plasmid-mediated PCases reported previously.
|
3f92e07e-704f-42a2-8e3d-4743f56a7065
| 0 |
Immunosuppressant activity of the ansamycins. The immunosuppressive effect of four analogues of rifampin and two streptovaracins on cell-mediated immunity has been determined. Tuberculin hypersensitivity in the footpads of immunized mice was inhibited by three of the rifampin analogues and by both streptovaracins. The observed in vivo immunosuppressive activity of the compounds tested was not correlated with their in vitro activity against mycobacterial growth but was associated with their toxicity in mice.
|
3f92e07e-704f-42a2-8e3d-4743f56a7065
| 1 |
These data indicate that some of the analogues of rifampin and the streptovaracins can significantly suppress cell-mediated immunity and suggest that other ansamycins may have significant immunosuppressant activity.
|
c7b9ef39-8475-4dcc-b0d0-1ec15a5e4ff8
| 0 |
In vitro susceptibility studies with josamycin and erythromycin. The in vitro activity of josamycin and erythromycin against five bacterial species was compared. In general, erythromycin was slightly more active by weight than josamycin, although both agents had a similar range of activity.
|
d748e20b-47ee-4512-8116-e31845b3045f
| 0 |
Two XX males diagnosed in childhood. Endocrine, renal, and laboratory findings. Two prepubertal boys with bilateral cryptorchidism were identified as 46,XX after nuclear sexing studies in several tissues. Gonadal histology and chromosome studies suggested that true hermaphroditism or mosaicism were unlikely. Xg blood grouping was informative in one patient.
|
d748e20b-47ee-4512-8116-e31845b3045f
| 1 |
Accepting paternity, this suggested either that both Xs were maternal, with loss, for example, of the male determining Y chromosome, or that the paternal X chromosome did not express, probably because of a deletion, the allele for the positive Xg blood group. The patients had normal thyroid stimulating hormone reserves but subnormal responses to human chorionic gonadotrophin stimulation, and may need hormonal replacement at puberty.
|
d748e20b-47ee-4512-8116-e31845b3045f
| 2 |
Both had renal anomalies. We suggest that chromosome analysis is essential when cryptorchidism, hypospadias, or microgenitalia are found and that an intravenous pyelogram is desirable.
|
a987a391-9d96-438c-8764-5fadf245d1f5
| 0 |
Establishment of a viable homograft cardiac valve bank: a rapid method of determining homograft viability. A method for determining the viability of homograft valves has been developed based on sequential measurements of glucose and pH levels of the culture medium in which cardiac valves have been maintained for short periods at 37 degrees C.
|
a987a391-9d96-438c-8764-5fadf245d1f5
| 1 |
Viable valves, as determined by tissue culture, showed a characteristic pattern of glucose utilization and pH reduction that was absent in nonviable valves. Upon explantation of valve leaflet fragments into tissue culture, only fragments from valves that metabolized glucose produced viable fibroblast cultures. The method reported here is rapid, requires no specialized equipment, is nondestructive, and can directly determine the viability of the valve homograft within 24 to 48 hours.
|
0464b822-7872-4ed9-bc6e-3b0eff5218fd
| 0 |
Resin hemoperfusion for acute drug intoxication. Eight patients with drug intoxication were hemoperfused on ten occasions at a blood-flow rate of 300 ml/min with a 650gm column of Amberlite XAD-4 resin, which is a macroreticular resin with a specific adsorptive attraction for lipid-soluble organic molecules.
|
0464b822-7872-4ed9-bc6e-3b0eff5218fd
| 1 |
Column clearances of glutethimide and a variety of barbiturates ranged from 207 to 300 ml/min for treatment sessions extending from 2 1/2 to ten hours. After ingestion of 75 gm of glutethimide, one patient received hemoperfusion on three successive days for nine, ten, and eight hours, respectively.
|
0464b822-7872-4ed9-bc6e-3b0eff5218fd
| 2 |
She recovered after the column removed over 30 gm of drug. The patients demonstrated dramatic clinical responses with no evidence of meaningful toxic reactions. Column hemoperfusion with Amberlite XAD-4 resin was simpler and more effective than any known method of removing barbiturates and glutethimide from the blood of patients with drug overdoses.
|
56c3fa4b-9d5f-4ba6-a96e-4895dacf4d3e
| 0 |
Increased mucociliary transport by adrenergic stimulation. Tracheobronchial clearance of inhaled 6mum Teflon particles (density 2 gm/cu cm) tagged with technetium 99m was studied in healthy subjects by external measurement of the radioactivity in the lungs for two hours. Clearance, salivary secretion, blood pressure, and heart rate were determined in eight subjects after double-blind, subcutaneous administration of 0.25
|
56c3fa4b-9d5f-4ba6-a96e-4895dacf4d3e
| 1 |
mg terbutaline sulfate, a beta-adrenoceptor stimulating compound and vehicle, respectively, in a crossover study. Terbutaline produced a marked increase in clearance and a slight increase in heart rate, but had no important effect on salivary secretion or blood pressure. The result indicates that the blood concentrations of catecholamines might be of importance for the regulation of the mucociliary transport rate.
|
4d54b1e4-17ae-4231-b3b0-af2b5c456a68
| 0 |
Platelet aggregation in portal cirrhosis. Primary and secondary platelet aggregation in response to adenosine diphosphate was studied in 24 patients with portal (Laënnec) cirrhosis and compared with platelet aggregation in 14 normal subjects. In 12 patients with cirrhosis, platelet aggregation was diminished when compared to controls. Of the 12 patients with impaired aggregation, 6 had elevated levels of fibrinogen-fibrin degradation products (FDPs), 11 had thrombocytopenia, 10 had shortened euglobulin lysis times, 11 had prolonged bleeding times, 4 had hypofibrinogenemia, and all had prolonged thrombin clotting times.
|
4d54b1e4-17ae-4231-b3b0-af2b5c456a68
| 1 |
The data suggest that elevated levels of serum FDPs do not explain fully the impairment of platelet aggregation or the prolongation of the thrombin clotting time that was noted in patients with advanced liver disease. A possible explanation for the prolongation of the thrombin clotting time is the presence of "altered" plasma fibrinogen.
|
d1745262-9a29-4e81-a09d-3ad3d9a8e245
| 0 |
Study of guinea pigs fed Swiss chard grown on municipal sludge-amended soil. Multi-element content of tissues. Swiss chard, field-grown on soil amended with 100 dry tons per acre of municipal sewage sludge from Washington, DC, was fed to guinea pigs for 28 days. Control animals were fed Swiss chard grown on unfortified soi.
|
d1745262-9a29-4e81-a09d-3ad3d9a8e245
| 1 |
Forty-one elements were determined in the sludge, the plant material, and liver, kidney, muscle, adrenal, and spleen tissues by neutron activation and other methods. Elevated concentrations of several elements found in the Swiss chard grown on the sludge-soil mixture also appeared at higher levels in certain of the animal tissues.
|
d1745262-9a29-4e81-a09d-3ad3d9a8e245
| 2 |
These included antimony in adrenal, cadmium in kidney, manganese in liver tissues, and tin in several tissues. The animals showed no observable toxicological effects.
|
b8cf887d-f61c-4208-a2fc-6993a486d4a1
| 0 |
[Counter-immunoelectrophoresis in the diagnosis of meningoencephalitis by Diplococcus pneumoniae and Hemophilus influenzae]. The presence of antigen of D. pneumoniae and H. influenzae was detected by counter-immunoelectrophoresis (CIE) in 113 LCR of children with central nervous system (CNS) infection (17 viral, 70 bacterial and 6 tuberculous).
|
b8cf887d-f61c-4208-a2fc-6993a486d4a1
| 1 |
From 41 normal children spinal fluid was obtained and used as control. Precipitation band was not observed in normal children cases of viral and tuberculosis meningitis. In 21 cases of bacterial meningitis, D. pneumoniae and H. influenzae was isolated in six cases each. In six cases of bacterial meningitis were positive both bacteriological study and CIE.
|
b8cf887d-f61c-4208-a2fc-6993a486d4a1
| 2 |
In 49 cases in which culture was negative only 13 gave positive CIE. When other strains of bacteria were isolated, no positive band was detected with CIE. This technic was regarded as useful for detecting etiologic agent in purulent meningitis.
|
0eba130a-a7ea-47d0-84a9-85688eef40c6
| 0 |
Alanine dehydrogenase of the N2-fixing blue-green alga, Anabaena cylindrica. The L-alanine dehydrogenase (ADH) of Anabaena cylindrica has been purified 700-fold. It has a molecular weight of approximately 270,000, has 6 sub-units, each of molecular weight approximately 43,000, and shows activity both in the aminating and deaminating directions. The enzyme is NADH/NAD+ specific and oxaloacetate can partially substitute for pyruvate. The Kampp for NAD+ is 14 muM and 60 muM at low and high NAD concentrations respectively.
|
8064ad44-7cfe-4de6-8883-b7e92af80fe2
| 0 |
Aromatic amino acid biosynthesis in Alcaligenes eutrophus H 16 III. Properites and regulation of anthranilate synthase. Properties and regulation of anthranilate synthase from Alcaligenes eutrophus H 16 were investigated. Anthranilate synthase was partially purified from crude extracts by affinity chromatography on tryptophan-substituted Sepharose, and was used for kinetic measurements. During the purification procedure the enzyme was stabilized by 50 mM L-glutamine or during chromatography on DEAE- cellulose and Sephadex G-200 with 30% glucerol, respectively.
|
8b56bfaa-b7e2-4dd0-b3bb-0f6923ff5f21
| 0 |
Influence of industrial toxic compounds on pregnancy. VI. Some tissue enzymes in pregnant guinea pigs exposed to the action of triethylenetetramine. Gamma-glutamyl transpeptidase activity in kidney homogenates, aspartate and alanine aminotransferase activities in liver homogenates, and cholinesterase activity in brain homogenates were determined in nonpregnant and pregnant guinea pigs exposed to absorption through the skin of the epoxy resin triethylenetetramine. Elevated activity of gamma-glutamyl transpeptidase in the kidneys of pregnant animals, and aspartate aminotransferase in the liver of nonpregnant guinea pigs were observed.
|
245f5f77-e9fb-44ba-afce-c4f1e3ee276d
| 0 |
[Histology and histochemistry of the seal ovaries and the age-related changes in the ovaries of the Greenland seal]. Histological and histochemical methods were used to study the ovaries of Greenland seal (Pagophoca groenlandica) from birth-time up to 30 years of age and mature females of Phoca vitulina and Erignathus barbatus.
|
245f5f77-e9fb-44ba-afce-c4f1e3ee276d
| 1 |
The ovary of the new-born Greenland seal has fetal medullary substance which is a provisory endocrinous gland producing not only sex hormones but also corticosteron. In other species of seals the intestinal cells of the medullary substance are the equivalent of this gland. Within 3-4 weeks after birth the reduction of the fetal medullary substance is completed, it is substituted by the connective tissue and the ovary acquires its typical structure.
|
245f5f77-e9fb-44ba-afce-c4f1e3ee276d
| 2 |
The rest of the fetal medullary substance is in the depth of the cortex and near the infundibulum of the ovary as lipofuscincontaining cells. When the maturation period approaches, the process of the follicle atresia regularly changes: the epithelium dies quicker, and the multiplication of intestinal cells increases.
|
245f5f77-e9fb-44ba-afce-c4f1e3ee276d
| 3 |
The ovaries of seals are rich in interstitial cells. Their amount cyclically changes. The cells producing steroid hormones always well hydrolize AS naphthyl-phosphates, the reaction with glycerophosphate is more variable. The connective tissue is poor in acid mucopolysaccharides, its amorphous substance in the ovary cortex is rich in protein.
|
245f5f77-e9fb-44ba-afce-c4f1e3ee276d
| 4 |
Senile changes of the ovary are noticed in the seal beginning from 20 years of age.
|
f7c8ae2e-c06e-41aa-b8ba-a406193856f5
| 0 |
[Endocrine cells of the gastric mucous membrane]. In order to obtain an additional information concerning a possible functional role of the main types of the endocrine cells (EC and ECL) on investigation of aspiration biopsy specimens taken from the middle third of the stomach in patients with ulcerative disease of the duodenum and chronic gastritis was carried out.
|
f7c8ae2e-c06e-41aa-b8ba-a406193856f5
| 1 |
Changes in morphology, distribution and number of the endocrine cells in pathology of the mucosa and in various acidity of the gastric juice were followed up. On the basis of the data obtained the conclusion is made that serotonin-producing (EC) cells seem to have nothing to do with the regulation of the activity of the fundal glands, whereas the enterochromaffin-like cells (ECL) influence the production of hydrochloric acid by pavement cells.
|
597d2628-afaf-4061-99a3-01b92d0de2b3
| 0 |
Tranquilizers or anti-depressants for chronic schizophrenics: a long term study. The relative efficacy of 4 tranquilizers was investigated in 66 chronic schizophrenics who had been hospitalized for 10.01 years (mean). The role of adding an anti-depressant was also studied. Following a 4 week placebo period, high dosage tranquilizers were given for 16 weeks and amitriptyline was added for the following 16 weeks.
|
597d2628-afaf-4061-99a3-01b92d0de2b3
| 1 |
Statistical analyses of the various change measures revealed that patients worsened significantly on placebo, all 4 tranquilizers were significantly better than placebo for symptom reduction and maximum improvement was attained within 16 weeks of tranquilizer administration. No significant differences in efficacy were observed among the 4 tranquilizers and addition of amitriptyline did not confer any additional therapeutic advantage.
|
04993545-2081-4a85-83d0-dd8918f21703
| 0 |
Physiological index as an aid in developing airline pilot scheduling patterns. A multiplicative and additive formula has been developed for assisting in the development of schedules for airline pilots and flight engineers. The formula is based on freshness/tiredness data derived from aircrews on world flights. It should materially assist those who develop the schedules to avoid, where possible, finalizing those crew patterns that would impose a severe physiologic load on cockpit personnel.
|
04993545-2081-4a85-83d0-dd8918f21703
| 1 |
The objective of the application of the formula is to assure that crew members retain adequate "physiologic reserve" in the course of flying various segments of a pattern. This enables them to absorb the stresses of schedule delays or disruptions, as well as unforeseen operational problems and flight emergencies.
|
cda9b79b-41d9-4bd7-bd42-ddcf1e0be499
| 0 |
A neutral collagenase from human gastric mucosa. Biopsy specimens of human gastric mucosa, maintained in culture for 7 days in the absence of serum, released a collagen-degrading enzyme into the medium. The yield of active enzyme reached a maximum after 2-3 days, and viable tissue, capable of protein synthesis, was essential for its production.
|
cda9b79b-41d9-4bd7-bd42-ddcf1e0be499
| 1 |
2. At 25 degrees C the enzyme attacked undenatured collagen in solution, resulting in a 55% loss of specific viscosity and producing the two products TCA and TCB characteristic of neutral-collagenase action. 3. Electron microscopy of segment-long-spacing crystallites of these reaction products showed the exact cleavage locus of the collagen molecules to be between bands 43 and 44 (I-43).
|
cda9b79b-41d9-4bd7-bd42-ddcf1e0be499
| 2 |
The larger TCA and smaller TCB products were fragments representing 77 and 23% respectively of the length of the collagen molecule. 4. Optimal enzyme activity was observed over the pH range 7.5-8.5 and a mol.wt. of approx. 38000 was derived from gel-filtration studies. 5.
|
cda9b79b-41d9-4bd7-bd42-ddcf1e0be499
| 3 |
The enzyme was shown to be inhibited by the human serum proteins alpha2-macroglobulin and a smaller component of mol.wt. approx. 40000; alpha1-anti-trypsin was not inhibitory. 6. EDTA, 1, 10-phenanthroline, cysteine and dithiothreitol all inhibited collagenase activity. 7. The gastric enzyme has properties similar to other well characterized collagenases, but differences exist with respect to its molecular size and the site of attack on the collagen molecule.
|
84cceb1f-477c-495c-8361-66e9cb813a81
| 0 |
Adsorption of glyceraldehyde 3-phosphate dehydrogenase on condensed monolayers of phospholipid. The adsorption of [14C] alkylated glyceraldehyde 3-phosphate dehydrogenase from rabbit muscle to condensed monolayers of phosphatidic acid was investigated under a variety of conditions. 2. The rate constant for association at 20 degrees C depended on ionic strength.
|
84cceb1f-477c-495c-8361-66e9cb813a81
| 1 |
At I/2=60mM the rate constant was 0.39min-1. At I/2=260mM it decreased to 0.27min-1. 3. The apparent association constant (Kass.) for adsorption at I/2=60mM was 1.06 X 10(6)M-1 and was strongly influenced by subphase changes in pH and ionic strength.
|
84cceb1f-477c-495c-8361-66e9cb813a81
| 2 |
Measurements of Kass. at 20 degrees and 5 degrees C gave a value for the apparent enthalpy change on adsorption of -33kJ-mol-1. Calculations of the apparent change in free energy and apparent entropy change for the adsorption process gave values of -34kJ-mol-1 and +2J-K-1-mol-1 respectively.
|
84cceb1f-477c-495c-8361-66e9cb813a81
| 3 |
4. Decreasing the amount of phosphatidic acid in the monolayer by replacement with phosphatidylcholine caused the shape of the adsorption isotherm to change from apparent hyperbolic to sigmoid. Subphase changes in pH or ionic strength did not affect the shape of the adsorption isotherm. However, adsorption of enzyme on monolayers of 100% phosphatidic acid in the presence of 1mM-CaCl2 was sigmoid in nature.
|
84cceb1f-477c-495c-8361-66e9cb813a81
| 4 |
5. It is concluded that glyceraldehyde 3-phosphate dehydrogenase binds to condensed charged monolayers by multiple electrostatic interactions. At low concentrations of phosphatidic acid in the monolayer or in the presence of Ca2+, this occurs in a two-step process and depends on lateral diffusion of phosphatidic acid for strong binding to take place.
|
e64de892-cac6-43e1-b347-0e1f3e9c3ef8
| 0 |
Blood pH and PaCO2 as chemical factors in myocardial blood flow control. The effect of metabolic and hypercapnic acidosis on myocardial blood flow was studied during intravenous infusions of hydrochloric acid solutions (n = 12) and during passive ventilation with 5% CO2 (n = 5) in anaesthetized, closed chest dogs.
|
e64de892-cac6-43e1-b347-0e1f3e9c3ef8
| 1 |
Below a pH of 7.2 metabolic acidosis at normal arterial CO2-tensions caused an increase of coronary blood flow and a decrease of coronary vascular resistance associated with a narrowed myocardial arteriovenous O2-difference, indicating vasodilation at unchanged myocardial oxygen consumption. In propranolol-pretreated dogs myocardial blood flow and coronary oxygen AV difference remained unaffected, suggesting that the coronary dilatory effect of metabolic acidemia involves beta adrenergic stimulation.
|
e64de892-cac6-43e1-b347-0e1f3e9c3ef8
| 2 |
Coronary vasodilation induced by increasing arterial pCO2 was found to the significantly greater as compared with the dilatory effect of metabolic acidosis at the same blood pH level. Blocking of beta receptors did not reduce the coronary response to increased arterial CO2-tensions. It is concluded that the coronary vasodilation observed during hypercapnic acidosis is neither mediated by a beta adrenergic stimulation nor dependent of the concomitant change in blood pH.
|
e64de892-cac6-43e1-b347-0e1f3e9c3ef8
| 3 |
The possible sites of the coronary dilatory actions of increased arterial CO2-tensions are discussed.
|
c14d6890-8a61-4ea5-b021-64980820dfbd
| 0 |
Enzymic hydrolysis of acetylcarnitine in liver from rats, sheep and cows. 1. The enzymic utilization of O-acetyl-l-carnitine other than via carnitine acetyltransferase (EC 2.3.1.7) was investigated in liver homogenates from rats, sheep and dry cows. 2. An enzymic utilization of O-acetyl-l-carnitine via hydrolysis of the ester bond to yield stoicheiometric quantities of acetate and l-carnitine was demonstrated;
|
c14d6890-8a61-4ea5-b021-64980820dfbd
| 1 |
0.55, 0.53 and 0.30mumol of acetyl-l-carnitine were utilized/min per g fresh wt. of liver homogenates from rats, sheep and dry cows respectively. 3. The acetylcarnitine hydrolysis activity was not due to a non-specific esterase or non-specific cholinesterase. O-Acetyl-d-carnitine was not utilized.
|
c14d6890-8a61-4ea5-b021-64980820dfbd
| 2 |
4. The activity was associated with the enriched outer mitochondrial membrane fraction from rat liver. Isolation of this fraction resulted in an eightfold purification of acetylcarnitine hydrolase activity. 4. The K(m) for this acetylcarnitine utilization was 2mm and 1.5mm for rat and sheep liver homogenates respectively.
|
c14d6890-8a61-4ea5-b021-64980820dfbd
| 3 |
6. There was a significant increase in acetylcarnitine hydrolase in rats on starvation and cows on lactation and a significant decrease in sheep that were severely alloxan-diabetic. 7. The physiological role of an acetylcarnitine hydrolase is discussed in relation to coupling with carnitine acetyltransferase for the relief of ;
|
c14d6890-8a61-4ea5-b021-64980820dfbd
| 4 |
acetyl pressure'.
|
b59696a4-5593-4aa3-b91f-05f6e170ac70
| 0 |
Creatine kinase equilibrium and lactate content compared with muscle pH in tissue samples obtained after isometric exercise. Muscle biopsies taken from the musculus quadriceps femoris of man were analysed for pH, ATP, ADP, AMP, creatine phosphate, creatine, lactate and pyruvate. Biopsies were taken at rest, after circulatory occlusion and after isometric contraction.
|
b59696a4-5593-4aa3-b91f-05f6e170ac70
| 1 |
Muscle pH decreased from 7.09 at rest to 6.56 after isometric exercise to fatigue. Decrease in muscle pH was linearly related to accumulation of lactate plus pyruvate. An increase of 22mumol of lactate plus pyruvate per g of muscle resulted in a fall of 0.5pH unit. The apparent equilibrium constant of the creatine kinase reaction (apparent K(CK)) increased after isometric contraction and a linear relationship between log(apparent K(CK)) and muscle pH was obtained.
|
b59696a4-5593-4aa3-b91f-05f6e170ac70
| 2 |
The low content of creatine phosphate in muscle after contraction as analysed from needle-biopsy samples is believed to be a consequence of an altered equilibrium state of the creatine kinase reaction. This in turn is attributed mainly to a change in intracellular pH.
|
ee0c156a-39a0-4ab0-a1de-ca1c84bb71bd
| 0 |
The microbial metabolism of acetophenone. Metabolism of acetophenone and some chloroacetophenones by an Arthrobacter species. 1. An organism that utilizes acetophenone as sole source of carbon and energy was isolated in pure culture and tentatively identified as an Arthrobacter sp. 2. Cell-free extracts of the acetophenone-grown organism contained an enzyme, acetophenone oxygenase, that catalysed an NADPH-dependent consumption of O(2) in the presence of the growth substrate;
|
ee0c156a-39a0-4ab0-a1de-ca1c84bb71bd
| 1 |
approx. 1mol of O(2) and 1mol of NADPH were consumed per mol of acetophenone oxidized. 3. Cell-free extracts also contained an enzyme capable of the hydrolysis of phenyl acetate to phenol and acetate. The amount of this esterase was increased markedly by growth on acetophenone.
|
ee0c156a-39a0-4ab0-a1de-ca1c84bb71bd
| 2 |
4. The observed products of the acetophenone oxygenase reaction by crude cell-free extracts were phenol and acetate. However, inhibition of the phenyl acetate esterase by paraoxon resulted in the formation of phenyl acetate from acetophenone. 5. A degradative sequence is proposed in which acetophenone is metabolized by an oxygen-insertion reaction to form phenyl acetate.
|
ee0c156a-39a0-4ab0-a1de-ca1c84bb71bd
| 3 |
Further metabolism occurs by hydrolysis of this ester. 6. The organism and extracts were shown to metabolize chlorinated acetophenones. The environmental implications of this observation are discussed.
|
7faa5e15-9dc0-4ca4-b0f7-f420cba3da93
| 0 |
Permeability to calcium of pigeon erythrocyte 'ghosts' studied by using the calcium-activated luminescent protein, obelin. 1. Obelin, the Ca(2+)-activated luminescent protein from the hydroid Obelia geniculata, was sealed inside pigeon erythrocyte ;ghosts' in order to investigate effects on their permeability of different methods of preparation and of the bivalent cation ionophore A23187.
|
7faa5e15-9dc0-4ca4-b0f7-f420cba3da93
| 1 |
2. Changes in free Ca(2+) within the ;ghosts' were studied by following the rate of luminescence of obelin. The possibility that the obelin might have been released from the ;ghosts' during an experiment was investigated by studying the release of inulin and pyruvate kinase from the ;
|
7faa5e15-9dc0-4ca4-b0f7-f420cba3da93
| 2 |
ghosts'. Less than 10% of the inulin or pyruvate kinase sealed within the ;ghosts' was released under any of the experimental conditions. 3. Triton X-100 (0.1-10%, v/v) made the ;ghosts' highly permeable to Ca(2+). In the presence of 1mm-Ca(2+) and Triton, 95-100% of the obelin was utilized within 10-20s.
|
7faa5e15-9dc0-4ca4-b0f7-f420cba3da93
| 3 |
4. A time-course of resealing ;ghosts' at 37 degrees C showed that over a period of 90min, the ;ghosts' became gradually less permeable to Ca(2+). ;Ghosts' which remained at 0 degrees C retained only a small concentration of obelin and ATP, and were highly permeable to Ca(2+).
|
7faa5e15-9dc0-4ca4-b0f7-f420cba3da93
| 4 |
5. Erythrocyte ;ghosts' resealed for 30min at 20 degrees C rather than 37 degrees C were more permeable to Ca(2+), as shown by the fact that 92% of the obelin in the ;ghosts' was utilized during the first 60s after the addition of 1mm-Ca(2+), as opposed to 44% for ;
|
7faa5e15-9dc0-4ca4-b0f7-f420cba3da93
| 5 |
ghosts' resealed at 37 degrees C. 6. Haemolysis at pH6.0 rather than 7.0 resulted in ;ghosts' which were highly permeable to Ca(2+) after resealing for 60min at 37 degrees C. Of the obelin in the ;ghosts', produced by haemolysis at pH6.0, 90% was utilized in the first 60s after the addition of 1mm-Ca(2+) compared with 23% for ;
|
7faa5e15-9dc0-4ca4-b0f7-f420cba3da93
| 6 |
ghosts' produced at pH7.0. 7. The bivalent cation ionophore A23187 increased the permeability of the ;ghosts' to Ca(2+). Maximum effects of the ionophore (16mug/ml) were obtained by preincubating the ;ghosts' with the ionophore A23187 (16mug/ml) in the presence of a low concentration of Mg(2+) and in the absence of Ca(2+).
|
8014f6ed-d846-40d7-a607-50d1f18beade
| 0 |
The action of tributyltin on energy coupling in coupling-factor-deficient submitochondrial particles. 1. Tributyltin at concentrations of approx. 1nmol/mg of protein induces respiratory control and lessens the protein permeability of coupling-factor-deficient submitochondrial particles. 2. At these concentrations or lower, it increases the P/O ratio of the particles to a small extent and inhibits the adenosine triphosphatase activity without greatly increasing its sensitivity to uncoupling agents.
|
8014f6ed-d846-40d7-a607-50d1f18beade
| 1 |
3. It fails to stimulate ATP-driven reversed electron transport or transhydrogenase, but stimulates the transhydrogenase driven by aerobic succinate oxidation. 4. The results indicate that, unlike oligomycin, tributyltin does not discriminate between damaged and intact ATP-synthesizing complexes. 5. The relationship between the oligomycin- and tributyltin-binding sites is discussed.
|
727e0ffc-40b4-48a4-b068-66f8505d3d24
| 0 |
Effects of the cardioselective beta-adrenergic receptor blocking agent metoprolol in angina pectoris. Subacute study with exercise tests. The effect of a cardioselective beta-adrenergic blocking agent, metoprolol, on symptoms and exercise tolerance was studied in 16 patients with angina pectoris. Metroprolol was compared with placebo at two dose levels (20 mg t.
|
727e0ffc-40b4-48a4-b068-66f8505d3d24
| 1 |
d.s. and 50 mg t.d.s.) in a double-blind trial in 14 patients. Compared with placebo, metroprolol caused a significant reduction of heart rate and systolic blood pressure during exercise, and consequently a reduction of the rate-pressure product. The reduction was greater with 50 mg t.
|
727e0ffc-40b4-48a4-b068-66f8505d3d24
| 2 |
d.s. than with 20 mg t.d.s. The exercise tolerance measured as total work increased significantly by 21 per cent during treatment with metroprolol 20 mg t.d.s., and by 17 per cent during treatment with 50 mg t.d.s. There was a reduction in the number of anginal attacks and in nitroglycerin consumption, and subjective improvement of angina pectoris at both dose levels of metroprolol.
|
727e0ffc-40b4-48a4-b068-66f8505d3d24
| 3 |
No signs of cardiac failure appeared during any of the four treatment periods. Heart volume showed no significant change. Unwanted effects were of the same frequency and severity during treatment with metroprolol at both dose levels as with placebo.
|
0051ba27-d21c-4a31-8de6-d8e65f08fea4
| 0 |
The availability of folates in man: effect of orange juice supplement on intestinal conjugase. The mechanisms of the low availability of endogenous folates in orange juice and the inhibitory effects on the availability of pteroylheptaglutamate (PteGlu7) caused by orange juice supplements were investigated in man by the use of simulated orange juice (containing the principal components:
|
0051ba27-d21c-4a31-8de6-d8e65f08fea4
| 1 |
citric acid, malic acid, etc.) with several different pHs. The endogenous folates in orange juice were identified as mainly 5-methyl reduced derivatives of pteroylpolyglutamates (40-45% pentaglutamate, 10-15% tetraglutamate, 30-40% monoglutamate, and the rest were tri-and diglutamates). The availability of PteGlu7 is decreased to 54% by supplementation with 600 g concentrated orange juice (pH 3.7
|
0051ba27-d21c-4a31-8de6-d8e65f08fea4
| 2 |
) and to 39% and 66% by the supplement of 24 g and 12 g citric acid (pH 3.7), respectively. Neutralization of 12 g citric acid to pH 6.4 largely reverses the inhibitory effect. On the other hand, the availability of pteroylmonoglutamate (PteGlu) is not influenced by a supplement of orange juice or citric acid.
|
0051ba27-d21c-4a31-8de6-d8e65f08fea4
| 3 |
The results suggest that the low availability of PteGlu7 is due to the inhibition of intestinal conjugase caused by the low pH. These observations suggest that pH of foodstuffs may be an important factor in the absorption of polyglutamate forms of folate.
|
9d52b6db-e311-403a-8eaa-bf359d50959d
| 0 |
The use of a single venous blood sample to assess oxygen binding in haemoglobin. The measurement of pH, PO2, PCO2 and SO2 in a single venous blood sample can be used to determine the P50 at standard or at in vivo conditions. This technique makes it feasible for a physician, firstly, to make an assessment of the net adaptation of the red cell to reductions in blood oxygen content or flow and, secondly, to make an initial assessment of whether a haemoglobin with altered affinity for oxygen is present in subjects with polycythaemia or anaemia.
|
f6030843-ddc2-4058-ac49-609e4dda2425
| 0 |
The state of energization of the membrane of Escherichia coli as affected by physiological conditions and colicin K. The bacterial protein colicin K, when added to sensitive Escherichia coli in the presence of 3,3'-dihexyloxacarbocyanine, cuases a doubling in fluorescence of the probe. Glucose and oxygen cause a decreased fluorescence while anoxia and cyanide cause a rise in fluorescence.
|
f6030843-ddc2-4058-ac49-609e4dda2425
| 1 |
These results in conjunction with the work of other laboratories suggest that colicin K causes a depolarization of the transmembrane electrical potential. Fluorescence in the absence of colicin K was relatively independent of KCl, NaCl, and MgCl2 concentrations below 0.1 M. Although colicin K caused rapid efflux of the K+ analogue 86Rb+, the fluorescence rise was only partially blocked by 0.13
|
f6030843-ddc2-4058-ac49-609e4dda2425
| 2 |
M KCl. The level of fluorescence caused by the action of colcin K was inversely proportional to the logarithm of the concentration of MgCl2 over the range of 2 muM to 4 mM. This suggests that a Nernst electrochemical potential for an anion can counteract a membrane depolarization caused by colcin.
|
f6030843-ddc2-4058-ac49-609e4dda2425
| 3 |
After colcin K action, the fluorescence of the carbocyanine could be further increased by anoxia or cyanide. The distribution of the weak base dimethyloxazolidinedione indicated that the pH in the interior of aerobic E. coli supplied with lactate was alkaline by 0.1 unit and unaffected by colicin. These results suggest that colicin K does not completely depolarize the membrane potential and does not interfere with the component of membrane energization generated by electron transport.
|
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.