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41.
The hormonal levels of the gonadotropins, the weight of selected organs and of the triceps surae as well as body composition were determined in Sprague Dawley rats at 3 and 6 weeks after intensive training with or without a methandrostenelone (Dianabol) supplement (0.35 mg/kg/day). The controls were sedentary rats of similar age and weight at the start of the experiment. The dianabol treated rats in the sedentary and exercise groups had a depression of plasma LH levels. There were no differences in body weight, specific gravity, lean body weight, fat or % fat between the two trained groups. Dianabol had no apparent effect on the measured parameters other than a depression of LH.  相似文献   
42.
The pattern of metabolic processes in lymphocytes of mice with Ehrlich ascites carcinoma depended on the stage of tumor growth.Translated from Byulleten Eksperimentalnoi Biologii i Meditsiny, Vol. 138, No. 11, pp. 563–566, November, 2004  相似文献   
43.
44.
Control of protein intake was studied in young rats that were allowed to choose between either protein-free and 55% casein diets or 15% and 55% casein diets. Animals on the protein-free vs. 55% casein regimen exhibited a lower weight gain, a lower cumulative energy intake and a greater cumulative total protein intake during the 13-day study compared to rats selecting between 15% and 55% casein. The daily average proportion of total food selected as casein by animals choosing between protein-free and 55% casein diets increased from 15% to 38% during the course of the study. In contrast, rats choosing between 15% and 55% casein chose 18-22% of total food as protein throughout the entire study. Long-term protein intake or protein selection did not correlate significantly with whole-brain contents of 5-HT or 5-HIAA. Our results suggest that protein intake is not regulated at a constant proportion of total calories, but is controlled between a minimum level that will support rapid growth and a maximum that, if exceeded, would require the animal to undergo substantial metabolic adaptation. The mechanism controlling protein selection may involve diet-induced changes in the brain content of total free indispensable amino acids.  相似文献   
45.
Summary IK and STF from male and female rats have been used to study in vitro the renal metabolism of B. in male rat tissue four lipid soluble metabolites (I–IV) have been found, I+II being more polar and III+IV being less polar than B. I and II have been identified as 11-dehydro-20-hydroxy-B and 20-hydroxy-B. The structure of III and IV remains to be determined. Renal tissue from female rats produced predominantly III indicating sexual variations of steroid metabolism in kidneys. — The literature has been reviewed which documents that the kidneys in addition to B metabolize A, cortisol, progesterone and other corticosteroids.
Abbreviations A Aldosterone - B Corticosterone - Alb Albumin - CS Corticosteroids - MCS/GCS Mineralo-/gluco-CS - IK Isolated (perfused) kidney - STF Suspended tubular fragments Supported by Deutsche Forschungsgemeinschaft Hi 97/16  相似文献   
46.
The role of work period duration as the principal factor influencing carbohydrate metabolism during intermittent exercise has been investigated. Fuel oxidation rates and muscle glycogen and free carnitine content were compared between two protocols of sustained intermittent intense exercise with identical treadmill speed and total work duration. In the first experiment subjects (n=6) completed 40 min of intermittent treadmill running involving a work : recovery cycle of 6 : 9 s or 24 : 36 s on separate days. With 24 : 36 s exercise a higher rate of carbohydrate oxidation approached significance (P=0.057), whilst fat oxidation rate was lower (P ≤ 0.01) and plasma lactate concentration higher (P ≤ 0.01). Muscle glycogen was lower post‐exercise with 24 : 36 s (P ≤ 0.05). Muscle free carnitine decreased (P ≤ 0.05), but there was no difference between protocols. In the second experiment a separate group of subjects (n=5) repeated the intermittent exercise protocols with the addition of a 10‐min bout of intense exercise, followed by 43 ± 5 min passive recovery, prior to sustained (40 min) intermittent exercise. For this experiment the difference in fuel use observed previously between 6 : 9 s and 24 : 36 s was abolished. Carbohydrate and fat oxidation, plasma lactate and muscle glycogen levels were similar in 6 : 9 s and 24 : 36 s. When compared with the first experiment, this result was because of reduced carbohydrate oxidation in 24 : 36 s (P ≤ 0.05). There was no difference, and no change, in muscle free carnitine between protocols. A 10‐min bout of intense exercise, followed by 43 ± 5 min of passive recovery, substantially modifies fuel use during subsequent intermittent intense exercise.  相似文献   
47.
Increased adrenal cortical activity and hypertrophy of adrenal glands associated with defeat and social subordination have been reported frequently in small mammals; these adrenal changes have been linked to impairments in immune response, glucose metabolism and reproductive performance. Similar studies in primates have produced variable results. The current study was undertaken to illuminate the effects of social status on the adrenal gland and to examine concurrent effects of social variables on other physiological systems in Macaca fascicularis, in an initial exploration of the hypothesis that high and low social status have different physiological consequences. Sixty adult male M. fascicularis were housed in social groups of n = 5, under either stable or unstable social conditions. It was found that subordinate animals had heavier adrenal glands and somewhat higher plasma glucose concentrations than dominants. In contrast, dominants had higher blood pressure and worsened atherosclerosis, under some conditions, than subordinates. These data appear to offer preliminary support for Henry and Stephen's hypothesis of differential arousal of dominant and subordinate animals.  相似文献   
48.
The metabolism of D-galactose is a major feature of red-algal physiology. We have cloned and sequenced a gene from the red alga Gracilaria gracilis that encodes a key enzyme of D-galactose metabolism, galactose-1-phosphate uridylyltransferase (GALT). This gene, designated GgGALT1, is apparently devoid of introns. A potential TATA box, four potential CAAT boxes, and a repeated sequence occur in the 5′-flanking region. The predicted 369-aa peptide shares significant sequence similarity with GALTs from other organisms (human, 47%; Saccharomyces cerevisiae, 49%; Solanum tuberosum, 49%). Southern-hybridization analysis reveals two related, but apparently not identical, GALT genes in the nuclear genome of G. gracilis. Sequence analysis indicates that the GgGALT1 enzyme lacks a rubredoxin “knuckle” motif, which in bacterial and fungal GALTs is involved in binding zinc. An open reading frame encoding a potential peptidyl tRNA hydrolase occurs 179 bp downstream from the GgGALT1 gene. Received: 6 April / 2 June 1998  相似文献   
49.
A new noninvasive method of measuring the structure and the electrical properties of bilayered biological tissues was evaluated as a potentially useful diagnostic means for detecting changes in subcutaneous tissues. First, the input impedance of an open-ended coaxial probe radiating into a bilayered model was calculated using a full-wave method, the results showed that the evanescen higher order modes do not have a significant influence on the reflection coefficient of muscle layer surface. Then, it was clearly proven that the phase shift and the modulus of the reflection coefficient of muscle layer surface depending on the frequency are useful to estimate the thickness of fat layer and the electrical properties of muscle respectively. The experimental results showed an excellent agreement with the theoretical relationship between the phase shift and the thickness. The sensitivity of estimation of the electrical properties of muscle was shown to be not enough for differentiating between normal and diseased deep tissue because of noises from the experimental systems.  相似文献   
50.
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