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81.
Central amygdaloid nucleus lesions in rats had no effect on recovery of preoperative body weight and food consumption levels. The brain damaged rats also recovered preoperative levels of water consumption as rapidly as control rats but then developed a mild but persistent hypodipsia. The experimental rats also drank less than control rats when food deprived and showed marginally reliable decreases in 0.1% quinine solution consumption and latency to consume a novel food. There was no detectable lesion effect on 0.1% saccharin solution consumption, exploration of a novel environment or formation of a learned taste aversion. It is suggested that the central amygdaloid nucleus has a role in mediating the relationship between food and water intake and in some taste mediated consummatory behavior.  相似文献   
82.
Body weight and food intake of lean and obese, male and female Osborne-Mendel rats following treadmill exercise were compared. Rats were assigned, separately by sex, to one of three diet groups; Group 1 was fed a low fat (10%) diet throughout the study, Group 2 was fed a high fat (55%) diet for 16 weeks and then switched to the low fat diet 1 week prior to exercise, and Group 3 was fed the high fat diet throughout the study. To control for differences in work output between the leanest and heaviest animals, exercise intensity was adjusted across groups such that all exercised rats had equivalent energy expenditure. After a 3 day training period, the exercise was successively increased over 8 days until a work output of 374.9J was reached. Relative to their respective controls, obese exercised males showed a reduction in body weight but no change in food intake. In contrast, exercised females showed no change in body weight or food intake, regardless of dietary condition.  相似文献   
83.
Four human subjects were fed ad lib with a bland diet for a period of 3 weeks. Their body weight decreased by 3.13 kg during this period. It was observed that the shift of the palatability response to sucrose solutions induced by a gastric glucose load (alliesthesia) was not affected by such a reduction of body weight. This result was compared to a previous experiment showing a decreased alliesthesia after a body weight loss due to the restriction of a palatable diet. These results confirm the role of the palatability of the diet on the maintenance of a body weight level and provide evidence for an interaction between the two factors in determining the oral satiation process.  相似文献   
84.
85.

Background

Increased body fat may be associated with an increased risk of developing an underlying pro-inflammatory state, thus leading to greater risk of developing certain chronic conditions. Immunoglobulin G has the ability to exert both anti- and pro-inflammatory effects, and the N-glycosylation of the fragment crystallisable portion is involved in mediating this process. Body mass index, a rudimentary yet gold standard indication for body fat, has been shown to be associated with agalactosylated immunoglobulin G N-glycans.

Aim

We aimed to determine the association between increased body fat and the immunoglobulin G glycosylation features, comparing body mass index to other measures of body fat distribution.

Methods

We investigated a sample of 637 community-based 45–69?year olds, with mixed phenotypes, residing in Busselton, Western Australia. Body mass index and the waist-to-hip and waist-to-height ratios were calculated using anthropometry, while dual-energy x-ray absorptiometry was performed to gain an accurate measure of total and area specific body fat. Serum immunoglobulin GN-glycans were analysed by ultra-performance liquid chromatography.

Results

Twenty-two N-glycan peaks were found to be associated with at least one of the fat measures. While the previous association of body mass index to agalactosylated immunoglobulin G was replicated, measures of central adiposity explained the most variation in the immunoglobulin G glycome.

Conclusion

Central adiposity is associated with an increased pro-inflammatory fraction of immunoglobulin G, suggesting that the android/gynoid ratio or waist-to-height ratio instead be considered when controlling for adiposity in immunoglobulin G glycome biomarker studies.  相似文献   
86.
Three groups of girl athletes — 10 gymnasts and 8 middle-distance swimmers averaging 14 years of age, and 8 middle-distance runners averaging almost 19 — were the subjects of this study. The maximal oxygen intake was determined by graded work load on a bicycle ergometer, certain pulmonary functions by spirometry, and total body potassium by wholebody counting of naturally radioactive40K. The total body water was obtained from measurements of deuterium oxide and application of the dilution principle, and creatinine excretion was determined from urine collections. Fat-free mass was calculated from total body water, and the amount of body fat was obtained by subtracting fat-free mass from body weight. Cell mass was calculated from total body potassium. Supporting evidence of leanness or fatness was provided by anthropometric measurements.The runners and swimmers achieved significantly higher maximal oxygen consumption per kg of body weight, fat-free mass, and cell mass; and the runners excelled the gymnasts in certain other pulmonary functions. Total body potassium in milliequivalents per kg of body weight, total body water expressed in percentage of body weight, and creatinine coefficients were similar in all three groups of subjects. These results indicated no differences in body composition. Calculations of body fat, fat-free mass, and cellular mass verified that conclusion; and supporting evidence was obtained from subcutaneous fat folds and from appraisal of leanness by corrected limb diameters or volumes, which also were similar in all three groups.  相似文献   
87.
Abstract Data on the metabolic responses to repeated endurance exercise sessions are limited. Thus, the aims of this study were to examine (1) the impact of prior exercise on metabolic responses to a subsequent exercise session and (2) the effect of different recovery periods between two daily exercise sessions on metabolic responses to the second bout of exercise. Nine male elite athletes participated in four 25-h trials: one bout of exercise (ONE), two bouts of exercise separated by 3 h of rest and one meal (SHORT), two bouts of exercise separated by 6 h of rest and two meals (LONG), and a trial with no exercise (REST). All exercise bouts consisted of 10 min cycling at 50% followed by 65 min at 75% of maximal O2 uptake. Compared to no prior exercise (ONE), a previous bout of exercise (SHORT) was followed by higher mean O2 uptake, heart rate (HR), rectal temperature (TR), excess post-exercise oxygen consumption and lower respiratory exchange ratio (R) during and after a similar exercise session 3 h later. A longer rest interval between the two exercise bouts (6 h versus 3 h) and an additional meal resulted in a decrease in O2 uptake, HR, TR and an increase in R during the second bout of exercise, but no effects on post-exercise metabolism were found. Thus, augmented metabolic stress was observed when strenuous exercise was repeated after only 3 h of recovery, but this was attenuated when a longer recovery period including an additional meal was provided between the exercise sessions.  相似文献   
88.
Analyses of natural feeding behavior in albino male Sprague-Dawley rats demonstrate that, when allowed to self-select from pure macronutrient diets (protein, carbohydrate and fat), these rats of the same genetic strain can be categorized into 3 subpopulations according to either their 24-h or their 12-h nocturnal patterns of nutrient intake. A majority of the animals (HC for high carbohydrate, 50% of the total population) consumed a diet rich in carbohydrate relative to protein or fat, while a smaller population of rats (HF, 30%) preferred the fat diet, and an even smaller population (HP, 20%) chose a high-protein diet. These 3 subpopulations, after a few weeks of maintenance on the diets, differed in their body weight, with the HF rats having a higher body weight than the HP animals, who tended to weigh more than the lightest HC rats. Whereas all subgroups exhibited a similar bimodal distribution of feeding during the nocturnal cycle, with peaks during the early and late dark periods, they were distinguishable on the basis of their nutrient consumption during specific phases of the dark cycle. This difference was most apparent in the early dark phase, when the 3 subgroups exhibited exaggerated preferences for the specific nutrient that was generally preferred over the 24-h cycle. This is in contrast to the middle dark phase, when diet preferences were attenuated or lost, and the late dark phase, when most rats were similar in showing an increased preference for protein and fat and a decreased preference for carbohydrate. The HF group was further distinguished by an unusually strong burst of feeding during the first 2 h of the dark period and an extra peak of feeding in the middle dark period (7th h), both of which were relatively high in fat content.  相似文献   
89.
Perception of our own bodies is based on integration of visual and tactile inputs, notably by neurons in the brain's parietal lobes. Here we report a behavioural consequence of this integration process. Simply viewing the arm can speed up reactions to an invisible tactile stimulus on the arm. We observed this visual enhancement effect only when a tactile task required spatial computation within a topographic map of the body surface and the judgements made were close to the limits of performance. This effect of viewing the body surface was absent or reversed in tasks that either did not require a spatial computation or in which judgements were well above performance limits. We consider possible mechanisms by which vision may influence tactile processing.  相似文献   
90.
大于胎龄儿脐血脂联素水平测定及其临床意义研究   总被引:1,自引:0,他引:1  
目的探讨血脂联素水平与大于胎龄儿发生的关系。方法研究对象为大于胎龄儿和适于胎龄儿各30例。应用酶联免疫吸附法(ELISA)测定脐血和产妇血脂联素浓度,用免疫比浊法测定甘油三酯(TG)、总胆固醇(TCH)、低密度脂蛋白-胆固醇(LDL-c)、高密度脂蛋白-胆固醇(HDL-c)的水平;并分析脐血脂联素水平与母血脂联素、新生儿性别、出生体重、体重指数、胎盘重量和血脂水平的相关性。结果①大于胎龄儿脐血浆脂联素水平低于适于胎龄儿,差异有非常显著性(P<0.01=;大于胎龄儿血TG、TCH、LDL-c、HDL-c的水平与适于胎龄儿比较差异均无显著性(P>0.05)。②大于胎龄儿血浆脂联素水平与新生儿出生体重、BM I、胎盘重量、脐血TG水平均呈显著负相关(r分别=-0.848、-0.785、-0.835,P均<0.001=,与母血脂联素水平、新生儿身长、孕前和分娩时产妇体重及其BM I、其它脐血脂成分无相关性(P>0.05)。母血脂联素水平与上述因素无相关性(P>0.05)③大于胎龄儿男婴和女婴脐血浆脂联素、血脂各成分水平比较差异均无显著性(P>0.05)。结论血脂联素水平的变化与大于胎龄儿的发生有关,测定脐血脂联素水平有助于判断大于胎龄儿的发展趋势,为早期预防糖尿病、心血管疾病等多种肥胖相关性疾病的发生开拓新的思路。  相似文献   
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