bluuebunny/crossref_metadata_2025_split huggingface dataset:
Studies on the New Zealand Strain of Genetically Hypertensive Rats
Authors: Simpson F. O. , Phelan E. L. , Clark D. W. J. , Jones D. R. , Gresson C. R. , Lee D. R. , Bird D. L. 
Published: August 2015

1. The New Zealand strain of rats with genetic hypertension (GH rats), the Japanese strain with spontaneous hypertension and the salt-sensitive strain of Dahl are now well established as three genetically pure lines for use in hypertensive research. Other pure lines not consciously selected for high blood pressure have also recently been shown to exhibit hypertension.
2. In the GH rats the inheritance of the blood pressure appears to be polygenic; thus a simple causation of the hypertension appears unlikely. The inheritance is also complex in the other pure lines of hypertensive rats.
3. In the GH rats variation in intake of sodium from 0.05% to 1% of the solid diet does not affect the development of the hypertension.
4. The renin-angiotensin-aldosterone system does not appear to play a primary role in the initiation of the hypertension in the GH rats. Compared with normotensive rats of the parent colony, plasma and renal renin are decreased, total exchangeable and carcass sodium are decreased, as are also the plasma volume and total extracellular fluid volume. Plasma sodium is normal and plasma potassium increased.
5. There is no evidence of a primary abnormality of catecholamine storage or turnover. Prevention of the development of the sympathetic nervous system from birth does not entirely abolish the difference in blood pressure between GH rats and comparably treated normotensive rats.
6. The increased peripheral resistance in blood-perfused hind limbs and tails of GH rats is due both to increased neurogenic and myogenic components and to a structural element. Increased vascular reactivity to a variety of constrictor agents is readily demonstrated in saline-perfused preparations.
7. The different strains of hypertensive rats may in their diversity mirror the differences between the various forms of human essential hypertension.
Plasma Volume Decrease and Elevated Evans Blue Disappearance Rate in Essential Hypertension
Authors: Ulrych Milos 
Published: August 2015

1. The disappearance rate of intravenously injected Evans Blue, plasma volume, cardiac output, and blood pressure were measured in seven normotensive and eighteen hypertensive subjects.
2. Plasma volume was found to be negatively correlated with the mean arterial pressure, Evans Blue disappearance rate and packed cell volume.
3. Faster disappearance rate of Evans Blue in hypertensive subjects may be due to an abnormality of mixing of the label or of the capillaries.
The Inactivation by Carbenoxolone of Individual Human Pepsinogens and Pepsins
Authors: Roberts N. B. , Taylor W. H. 
Published: August 2015

1. Carbenoxolone, in suspension at pH 4·0, inhibits swine pepsin A, and human pepsins 1, 3 and 5. Human pepsin 5 is the most readily inhibited, and human pepsin 1 the least.
2. Inhibition occurs by a process which is time-dependent, temperature-dependent and proportional to the quantity of carbenoxolone suspended.
3. Carbenoxolone, in solution at pH 7·4 and pH 8·0, inhibits the activation of the total pepsinogens of human gastric mucosal extracts and of the individual pepsinogens 1, 3 and 5. Pepsinogen 1 was the most readily inhibited, pepsinogen 5 the least.
4. Chymotrypsin was readily inhibited by carbenoxolone at pH 7·4 and 8·0. Trypsin was not inhibited at pH 7·4 but was inhibited, relatively weakly, at pH 8·0. Pronase was weakly inhibited at pH 7·4 and 8·0 but papain was weakly activated.
5. Carbenoxolone is therefore not a general enzyme inhibitor but shows specificity for enzymes (pepsins and chymotrypsin) which split proteins at the same bonds, rather than for enzymes with similar active centres (chymotrypsin and trypsin).
6. The results suggest that, in vivo, carbenoxolone might diminish peptic activity in three ways: by inactivating pepsinogens irreversibly in the mucosal cells or at some point before their activation to pepsins; by inhibiting pepsins irreversibly in the gastric lumen; and by binding pepsins in the lumen without destroying their activity but decreasing their effective concentration.
7. These results are compatible with the hypothesis that pepsins, and pepsin 1 particularly, are factors in the aetiology of peptic ulcer.
Retention of a Single Oral Massive Dose of Vitamin A
Authors: Pereira Sheila M. , Begum Almas 
Published: August 2015

1. Six pre-school children with normal intestinal absorption were given 100000 μg of retinyl palmitate and 14·4 μCi of [11,12-3H]retinyl acetate.
2. The absorption, excretion and retention of the label were determined.
3. The children retained 23–54% of the label.
4. The inefficacy of the massive dose as a prophylaxis against deficiency is discussed.
Maximum Motor Nerve Conduction Velocity in XYY Males
Authors: Wright M. O. 
Published: August 2015

1. Maximum motor nerve conduction velocities were determined under standard conditions for the median and ulnar nerves in the right forearm in males: (a) from the general population, (b) from a subnormality hospital, and (c) in males with the XYY sex chromosome abnormality. Distal latencies for these nerves were also measured.
2. No significant differences in maximum peripheral motor nerve conduction were found between the two control populations from the general population and from the subnormality hospital.
3. The maximum motor conduction velocity in the median nerve in the XYY group was significantly slowed when compared with both control groups. In the case of the ulnar nerve, maximum motor conduction was significantly slowed when compared with the general population, but not when compared with the subnormality hospital group.
4. There were no significant differences in the mean distal latencies of either the median or ulnar nerves between the two control groups.
5. In the XYY group, the distal latency in the ulnar nerve was significantly prolonged when compared with both control groups. In the case of the median nerve, the distal latency was prolonged significantly when compared with the general population; when the comparison was made with the subnormality hospital group significant prolongation was also observed but was less marked.
The Respiratory Response to Chronic Metabolic Alkalosis and Acidosis in Disease
Authors: van Ypersele de Strihou C. , Frans A. 
Published: August 2015

1. The respiratory response to chronic metabolic alkalosis was defined on the basis of 182 determinations of the arterial blood pH, Pco2, HCO3− concentration and Po2 obtained in thirty uraemic patients undergoing chronic haemodialysis. Plasma bicarbonate concentrations, [HCO3−], ranged from 20 to 38 mmol/l before dialysis, and were elevated by increasing the acetate content of the dialysate.
2. The calculated arterial carbon dioxide tension (Pa,co2) was linearly related to HCO3−, Pa,co2 reaching 50 mmHg at a [HCO3−] of 37.5 mmol/l. This response was virtually identical with that previously reported in chronic metabolic acidosis. The 95% confidence limits of the respiratory adaptation to chronic metabolic acid-base disorders were calculated for [HCO3−] ranging from 11 to 38 mmol/l.
3. Analysis of the individual response lines of thirteen patients revealed no difference among their slopes but significant differences among their elevations. Each subject appears thus to have his own threshold to acid-base stimuli.
4. Hypoxaemia developed with increasing [HCO3−], Pa,o2 falling in a curvilinear fashion to reach 70 mmHg at a [HCO3−] of 37.5 mmol/l.
Studies on the Pathogenesis of Fever in Renal Carcinoma
Authors: Cranston W. I. , Luff R. H. , Owen D. , Rawlins M. D. 
Published: August 2015

1. Endogenous pyrogen (EP) was detected in tumour extracts from four patients with renal carcinoma and fever. No EP was detected in extracts of tumours from six afebrile patients or in extracts of normal kidney.
2. Tumour slices from one febrile patient released EP into a nutrient incubation medium; this process was suppressed by the presence of cycloheximide. Tumour slices from an afebrile patient did not release EP on incubation.
3. Leucocytes from the peripheral blood of two febrile patients with renal carcinoma did not yield EP on incubation in saline.
4. The production of EP by leucocytes ‘activated’ by 2 h incubation with a Proteus endotoxin was not inhibited by cycloheximide.
5. It is suggested that fever associated with renal carcinoma is caused by the release of EP within the tumour.
The Effect of Ethanol on the Cough Reflex
Authors: Berkowitz H. , Reichel J. , Shim C. 
Published: August 2015

1. Coughing was induced in ten healthy subjects with various threshold concentrations of nebulized citric acid. The citric acid aerosol method of cough induction proved a reliable and reproducible tool for assessing the cough threshold in an individual. The subjects were retested after consumption of 1 ml of ethanol/kg body weight. Coughing was significantly suppressed in nine of the ten subjects.
2. The marked suppression of the cough reflex by the moderate amounts of ethanol used in this study provides confirmatory evidence for the suspected causal links between ethanol abuse and certain pulmonary infections caused by aspiration.
The Effect of Simulated Metabolic Acidosis on Intracellular pH and Lactate Metabolism in the Isolated Perfused Rat Liver
Authors: Lloyd M. H. , Iles R. A. , Simpson B. R. , Strunin J. M. , Layton J. M. , Cohen R. D. 
Published: August 2015

1. The relationship between extracellular pH (pHe), intracellular pH (pHi) and lactate uptake was studied in the isolated perfused rat liver during simulated metabolic acidosis.
2. pHi fell to a considerably less extent than pHe when the latter was decreased from pH 7·4 to 6·7.
3. The liver took up lactate when pHi was greater than 7·0; at lower values of pHi lactate output occurred.
4. The relevance of these observations to the control of hepatic pHi and lactate metabolism is discussed.
Plasma Lipid and Lipoprotein Abnormalities in Patients with Malabsorption
Authors: Thompson Gilbert R. , Miller J. Paul 
Published: August 2015

1. Plasma lipids and lipoproteins have been studied in control subjects and patients with various types of steatorrhoea.
2. Low plasma cholesterol levels were found in malabsorbers and were associated with decreased amounts of low-density lipoprotein (LDL) in males and high-density lipoprotein (HDL) in females.
3. Serum triglyceride levels were normal in males, but exceeded control values in some of the females, due to an increase in very-low-density lipoprotein.
4. LDL composition was abnormal in both male and female malabsorbers, with a decreased proportion of cholesterol ester and an increased proportion of triglyceride. There was also an increased proportion of triglyceride in HDL.
5. These findings show that malabsorption markedly influences not only the concentration but also the composition of plasma lipoproteins.
The Absorption of the Diastereoisomers of 5-Methyltetrahydropteroylglutamate in Man: A Carrier-Mediated Process
Authors: Weir D. G. , Brown J. P. , Freedman D. S. , Scott J. M. 
Published: August 2015

1. The two diastereoisomers of 5-methyltetrahydropteroylglutamate, the form of folate that predominates in food and bile, were prepared chemically.
2. Their intestinal absorption was compared by means of the urinary-excretion method of 3H-labelled compounds and it was found that the naturally occurring biologically active isomer was excreted to a greater extent. Studies of the clearance of the two forms after intravenous injection showed that this difference was due to preferential intestinal absorption of the naturally occurring isomer.
3. In four patients with coeliac disease, the absorption of the naturally occurring isomer was depressed to the same range as the inactive isomer.
4. Since the two diastereoisomers are chemically inseparable, these results indicate that a carrier-mediated process is involved in the human intestinal absorption of this form of reduced folate.
Renal Handling of Calcium, Magnesium, Inorganic Phosphate and Hydrogen Ions during Prolonged Exposure to Elevated Carbon Dioxide Concentrations
Authors: Gray S. P. , Morris J. E. W. , Brooks C. J. 
Published: August 2015

1. Fifteen healthy young men were exposed to an atmosphere of 0–7% CO2 in air for 7 weeks.
2. For 1 week before and during the exposure to CO2, serum calcium, magnesium and inorganic phosphate (Pi) levels were measured at intervals, together with 24 h urinary excretion of these three components, and net urinary acid excretion.
3. The urinary excretion of Ca2+, Mg2+ and Pi fell during exposure to CO2, whereas the serum levels of these components increased.
4. Serum levels of calcium were inversely correlated with urinary Ca2+ excretion both in control conditions and during exposure to CO2
5. An increase in urinary acid excretion in the third to fourth week of exposure to CO2 was associated with an increase in the urinary excretion of Ca2+, but not of Mg2+.
6. It is suggested that there is a difference from the normal in the renal handling of H+ and Ca2+ ions during exposure to CO2 which may lead to a retention of Ca2+ in the tissues.
The Hydrolysis of Glycine Oligopeptides by Guinea-Pig Intestinal Mucosa and by Isolated Brush Borders
Authors: Peters T. J. 
Published: August 2015

1. The relative rates of hydrolysis of a series of glycine homopeptides by guinea-pig small intestinal mucosa and by isolated brush borders have been studied. Oligopeptides up to and including hexaglycine were hydrolysed. No activity was detected against a series of homopolypeptides of molecular weight 10000–100000.
2. Except for activity against diglycine, the peptidase activity was greater in the brush-border fraction than in the original homogenate. The relative activity of the peptidase in the brush borders compared to the homogenate increased with increasing length oligopeptide substrate.
3. Analysis of the enzyme reaction products indicated that the brush border contained an exopeptidase. Studies with peptide derivatives containing N- and C-terminal blocking groups and with tetraglycine synthesized with either the N- or C-terminal residues labelled, demonstrated that the brush borders contained an amino-oligopeptidase.
4. Studies with inhibitors and with purified gastric and pancreatic enzymes indicated that this glycine oligopeptidase activity was not due to enzymes from the intestinal lumen which had been adsorbed to the brush borders.
The Effects of Therapeutic Decrease in Packed Cell Volume on the Responses to Exercise of Patients with Polycythaemia Secondary to Lung Disease
Authors: Harrison B. D. W. , Davis Jane , Madgwick R. G. , Evans Marion , Prime F. J. 
Published: August 2015

1. Progressive exercise and circulatory studies are reported on a selected group of patients with hypoxaemia and secondary polycythaemia before and after therapeutic decrease of packed cell volume.
2. A significant increase in exercise tolerance was demonstrated in a group of seven patients who claimed subjective benefit from the treatment.
3. No important circulatory changes were detected at rest after treatment.
4. During steady exercise mean pulmonary artery pressure at any given cardiac out-put was lower after treatment suggesting a fall in pulmonary vascular resistance.
5. During steady exercise oxygen consumption was increased in five of six patients subjectively improved by the treatment but no consistent changes in arterial lactate concentration or lactate/pyruvate ratio were observed.
Effect of High-Salt, High-Carbohydrate, Low-Protein Diet on Hypertension in the Rat
Authors: Ueda Hideo 
Published: August 2015

1. High-salt, high-carbohydrate and low-protein diet induces remarkable elevation of blood pressure in spontaneous hypertensive rats (SHR).
2. These animals have low serum potassium, low blood urea nitrogen and high blood sugar.
3. Heart weight is increased in proportion to the elevation of blood pressure.
4. Kidney weight of rats receiving the high-salt, high-carbohydrate and low-protein diet was, by contrast, smaller than SHR receiving a normal diet.
5. The kidneys of SHR receiving a high-salt, high-protein diet were twice as heavy as the kidneys of normal rats.
6. Similar dietary modifications in Goldblatt hypertensive rats to those in SHR produced similar changes in blood pressure and heart weight.
Long-Term Study of Relationships between Blood Pressure, Age and Body Weight in Steelmill Workers
Authors: Ulrych M. , Tauber J. , Shapiro A. P. 
Published: August 2015

1. In 404 male steelmill workers blood pressure and body weight were followed for 15–25 years and their relationships analysed.
2. It appears that age on average has a negligible influence on diastolic pressure and has a positive influence on systolic pressure only after 45 years of age.
3. In contrast to this, weight gain influences both pressures positively regardless of age.
Electrolytes, Environment and Blood Pressure
Authors: Langford H. G. , Watson Robert L. 
Published: August 2015

1. Studies to explain a significant socioeconomic and rural-urban blood pressure gradient found in central Mississippi are reported.
2. 24 h sodium excretion alone fails to explain the differences found, and fails to correlate with blood pressure.
3. A single 24 h determination of electrolyte excretion correlates modestly with the mean of 6 days' collection. Three days' collection and blood pressure determination is a reasonable compromise.
4. The urinary Na/Ca ratio is significantly higher in specimens from rural black girls compared with urban girls, and significantly higher in specimens from those with systolic pressure > 125 mmHg compared with those with < 105 mmHg pressure.
5. The urinary Na/K ratio of black girls was significantly higher than that of white girls of the same age, as was their blood pressure.
6. No correlation between blood pressure and urinary electrolytes could be found in black women aged between 35 and 45.
Sympathetic Activity in Peripheral Nerves of Normo- and Hypertensive Subjects
Authors: Wallin B. G. , Delius W. , Hagbarth K.-E. 
Published: August 2015

1. In hypertensive patients the general pattern of spontaneously occurring sympathetic activity (SA) as well as the sympathetic responses to various manoeuvres are similar to those of the normotensive controls.
2. This suggests that the multi-unit SA recorded in muscle and skin nerves of hypertensive patients are made up of impulses from the same fibre populations as in normotensive subjects and that the outflow of these impulses is controlled by similar mechanisms in the two groups.
3. More quantitative evidence obtained under standardized external conditions is necessary before it can be decided whether there is an increased strength of the sympathetic outflow to the skin in hypertensive patients.
The Thymus of Spontaneously Hypertensive Rats: Light- and Electron-Microscopic Studies
Authors: Rojo-Ortega J. M. , Yeghiayan E. , Genest J. 
Published: August 2015

1. The present investigation was undertaken to study the possibility that hypertensive vascular disease could be associated with changes in the morphology of the thymus.
2. Using light- and electron-microscopic techniques, the thymus of spontaneously hypertensive rats (SHR) with (1 year of age) and without (10 weeks of age) severe vascular lesions were compared with appropriate controls.
3. The thymus of SHR with severe hypertensive vascular disease showed: (a) marked hyperplasia and hypertrophy of the epithelial cells, with ultrastructural features of hypersecretory activity, and (b) in contrast to the paucity of plasma cells in the thymus of the control animals, the SHR had numerous plasma cells.
4. These observations may suggest the involvement of an autoimmunological mechanism in the development of the vascular lesions in SHR.
Hypotensive Effect of Oxprenolol in Mild Hypertension: A Co-Operative Controlled Study
Authors: Muiesan G. , Motolese M. , Colombi A. 
Published: August 2015

1. In a multicentre double-blind study, oxprenolol (OX) hypotensive effect was investigated in 329 patients with mild to moderate hypertension.
2. A factorial experimental design with three factors was chosen: OX mg/day 0, 20, 40, 60, 80; dihydrazinophthalazine (DHZ) mg/day 0, 30; and hydrochlorothiazide (HCH) mg/day 0, 30. Each treatment was carried out for a period of 4 weeks after an adequate placebo period.
3. Independently of the association with DHZ and/or HCH, OX yielded a hypotensive effect linearly related to dose (P < 0.05) for systolic and diastolic pressure in the standing position, but only for diastolic pressure in the supine position.
4. The addition of DHZ and/or HCH to OX at 80 mg/day caused a significant increase in the final hypotensive effect.
The Effect of Practolol (‘Eraldin’) in the Long-Term Treatment of Severe and Moderate Hypertension
Authors: Fulton R. M. , Fulton E. Hilda , Green K. G. 
Published: August 2015

1. The results of a clinical trial of practolol in sixty-one patients with moderate and severe hypertension are presented. Alone or with a diuretic the drug was highly effective in thirty patients, and in a further eight who developed side effects. Effectiveness was not directly related to dosage or blood levels of drug, or to the severity of the hypertension.
2. Nine non-responders to practolol were found to respond to propranolol which is probably a more widely effective antihypertensive agent. Nevertheless, the additional safety factors of practolol and twice daily dosing make it first choice for many patients. We have been impressed by the ability of both β-blocking drugs to control blood pressure without impairing the quality of every-day life.
Age-Dependent Changes of Plasma Renin Concentration in Humans
Authors: Hayduk K. , Krause D. K. , Kaufmann W. , Huenges R. , Schillmöller U. , Unbehaun V. 
Published: August 2015

1. Plasma renin concentration (PRC) in newborns greatly exceeded PRC in children and adults. PRC in cord plasma of newborns was higher than peripheral venous PRC in their mothers. PRC in the newborns increased further in the first 48 h post partum and then gradually decreased.
2. The mean PRC of healthy children and adults on free sodium intake decreased with age by an exponential function.
3. The absolute increase of PRC in response to upright posture (PRCupright — PRCrecumbent) decreased with age. The relative increase of PRC in response to upright posture (PRCuprjght:PRCrecumbent) remained unchanged with age, the PRC in upright posture being about twice the basal PRC in all age groups.
Plasma Renin Activity and Plasma Renin Substrate in Hypertension Associated with Steroid Excess
Authors: Krakoff L. R. , Mendlowitz M. 
Published: August 2015

1. Plasma renin activity and plasma renin substrate were measured by radioimmunoassay of generated angiotensin I in patients with steroid excess syndromes. Significant increases in substrate were observed in patients with Cushing's syndrome, during glucocorticoid therapy and on oral contraceptive agents. Suppression of plasma renin activity occurred only in primary aldosteronism.
2. The Michaelis constant (Km) for the reaction between renin and substrate in plasma at physiological pH (7.4) was also determined. The extent to which elevated plasma renin substrate increases the velocity of angiotensin I formation was then calculated.
3. In patients with Cushing's syndrome, glucocorticoid therapy or oral contraceptive use, elevated renin substrate coupled with failure of suppression of circulating renin results in increased angiotensin I formation.
The Effect of Chronic Sodium Loading and Sodium Restriction on Plasma and Renal Concentrations of Prostaglandin a in Normal Wistar and Spontaneously Hypertensive Aoki Rats
Authors: Zusman R. M. , Forman B. H. , Schneider G. , Caldwell B. V. , Speroff L. , Mulrow P. J. 
Published: August 2015

1. In normal and hypertensive rats prostaglandin A (PGA) in plasma and kidney increased on low sodium intake and decreased on high sodium intake.
2. Plasma and renal concentrations of PGA were higher in spontaneously hypertensive rats than in normal Wistar rats in each dietary group.