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221.
222.
The mechanisms underlying physical exercise-induced hyperthermia may be species specific. Therefore, the present study aimed to investigate the effects of exercise intensity and ambient temperature on the core body temperature (T core) of running mice, which provide an important experimental model for advancing the understanding of thermal physiology. We evaluated the influence of different protocols (constant- or incremental-speed exercises), treadmill speeds and ambient temperatures (T a) on the magnitude of exercise-induced hyperthermia. To measure T core, a telemetric sensor was implanted in the abdominal cavity of male adult Swiss mice under anesthesia. After recovering from the surgery, the animals were familiarized to running on a treadmill and then subjected to the different running protocols and speeds at two T a: 24 °C or 34 °C. All of the experimental trials resulted in marked increases in T core. As expected, the higher-temperature environment increased the magnitude of running-induced hyperthermia. For example, during incremental exercise at 34 °C, the maximal T core achieved was increased by 1.2 °C relative to the value reached at 24 °C. However, at the same T a, neither treadmill speed nor exercise protocol altered the magnitude of exercise-induced hyperthermia. We conclude that T core of running mice is influenced greatly by T a, but not by the exercise protocols or intensities examined in the present report. These findings suggest that the magnitude of hyperthermia in running mice may be regulated centrally, independently of exercise intensity.  相似文献   
223.
Haplotypes derived from five polymorphic restriction sites in the beta-globin gene cluster were investigated in 139 individuals from five different Brazilian Indian tribes by the polymerase chain reaction (PCR). Eight haplotypes were identified. Haplotypes 2 (+????) and 6 (?++?+) were the most frequent and were common to all tribes. Their prevalences ranged from 60% to 93% and from 3% to 18%, respectively. Average heterozy-gosity measured by the Gini-Simpson index is markedly reduced among these Brazilian Indians when compared with Europeans (56%), but much less (8%) in relation to Asiatics, suggesting the absence of an important bottleneck effect in the early colonization of South America. The coefficient of gene differentiation (GST′) was estimated as 0.082 among six Brazilian Indian tribes, but when only three Tupi-Mondé-speaking tribes were considered, this estimate was reduced to 0.030. © 1995 Wiley-Liss, Inc.  相似文献   
224.
Three isoproteic and isoenergetic diets containing fish meal as a protein source (control diet) or incorporating 10 and 20% of protein from mycelia Penicilium sp. as a fish meal substitute were tested during three months for eel fingerlings growth. Some preliminary “in vitro” experiments on the L-Lysin intestinal absorption in the presence and in the absence of Penicilin (500 mg/l) after 17 h of contact show a positive effect of this antibiotic. No residues of Penicilin were detected in carcass of eels fed 7 days with 100 mg/kg Penicilin in the food. The present results show that the use of Penicilin mycelia in eels diets will have the advantage of increasing growth without any appreciable change in the quality of the carcass and also, eventually, reductions of nitrogen excretion with a positive effect in effluent quality.  相似文献   
225.
Maltopentaose and olive pulp xylo-oligosaccharides and the correspondent alditol derivatives were analysed by ESI-MS and ESI-MS/MS. The ESI-MS spectrum of maltopentaose and maltopentaose alditols showed [M+Na]+and [M+H]+ ions. ESI-MS spectrum of xylo-oligosaccharides and their alditols showed [M+Na]+of neutral (Xyl3–6) and acidic (Xyl2–3MeGlcA and Xyl2–3GlcA) xylo-oligosaccharides. The ESI-MS/MS spectra of maltopentaose and underivatised xylo-oligosaccharides presented fragments of glycosidic cleavages attributed to B/Z and C/Y ions. On the other hand, MS/MS spectra of the correspondent alditols showed glycosidic cleavages unambiguously identified as B-type and Y-type ions. Y-type fragment ions showed higher abundance in the MS/MS spectra of the alditol derivatives when compared to the non-reduced samples. The study of the oligoxylosyl alditols fragmentation permits to distinguish fragmentation pathways that occur both from the reducing end and from the non-reducing end of the xylan chain, allowing to obtain more information about the localization of the acidic substituent along the glucuronoxylan backbone.  相似文献   
226.
Hydrostatic pressure elevated to 500 kPa for 14 days was found to affect hepatic 7‐ethoxyresorufin‐O‐deethylase (EROD), oxidized protein (POx), protein yield and branchial Na+–K+‐ATPase. No effect on glutathione‐S‐transferase (GST), superoxidase dismutase (SOD), catalase (CAT), lipid peroxidation (LP), acetylcholinesterase (AChE), butyrylcholinesterase (BChE), condition factor (K) and hepato‐somatic index (IH) was encountered.  相似文献   
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