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561.
562.
The objectives of the study were to determine the chemical constituents of rainbow trout (Salmo gairdneri) during the first 14 months of life, to study the effects of starvation on the body composition of trout, and to measure organ weights during the first 14 months of life. Body fat and protein content as a percentage of body weight increased with age, the water content declined, and the ash content remained constant during the first 14 months of life. There were no significant differences in body composition between immature male and female rainbow trout. Total body ions as a proportion of ash content decreased until the 10th month and then began to increase. During starvation, fat was used as the primary source of energy while water and ash content increased and protein content remained constant as a percentage of body weight. The gall bladder, liver, and air bladder remained relatively constant as a percentage of body weight during the first year of life. As body weight increased, the relative weight of brain, heart, and digestive system decreased while the gonad and spleen weight increased.  相似文献   
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Summary Culture studies revealed that 54.3 % of 70 mouth samples and 15.1 % of 371 throat samples from captive male and female baboons contained yeasts.Candida albicans was found to be the highest single species isolated from the oral cavity of both sexes, with the exception ofTrichosporon, which was slightly higher in the mouths of female baboons.There is a slight indication that the yeast flora of the female oral cavity is higher than that of the male. Similarly, there is a close parallelism between the oral mycoflora of human beings and that of the baboons studied.  相似文献   
566.
Human adenovirus cloning vectors based on infectious bacterial plasmids   总被引:8,自引:0,他引:8  
By making use of the fact that human adenovirus DNA circularizes in infected cells, and that circular forms of the viral genome are infectious, we have developed an improved adenovirus-based cloning system. A deletion mutant of adenovirus type 5 (Ad5) with deletions in early regions 1 (E1) and 3 (E3) was converted to a bacterial plasmid which can regenerate infectious virus following transfection into human 293 cells. A single XbaI recognition site in the deleted E3 region serves as a site for the insertion of foreign DNA. We have used this system to clone a number of genes into the Ad5 genome and describe the insertion of the neomycin/G418 resistance marker into Ad5 as an example.  相似文献   
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Many investigators have sought, but failed to find, ethnic differences in the number and regional distribution of active sweat glands. In this study measurements have been made of sweat secreted on one hand and also on the whole body of Whites and Blacks walking in desert heat. Whites numbered 31 men and 27 women, ages 30 to 88 years; there were 21 Black men and 31 Black women, ages 16 to 61 years. Each walked on three occasions for 1 hour at a rate that required an oxygen consumption of about 40% of aerobic capacity. Ambient temperature ranged from 32 to 44°C in 1979 and 1980; means were 38.4°C in 1979 and 36.7°C in 1980. There was no sweat in the gloves of many Blacks; this was true of only a few Whites. Volume of body sweat increased in both races with rate of walking; volume of hand sweat increased more in Whites than in Blacks. The Mann-Whitney test revealed that volumes of hand sweat were significantly greater for Whites than for Blacks. It was concluded that in desert walks most Whites and few Blacks sweat freely on their hands. In samples of hand sweat, Na+, K+, and Cl? were determined. Concentrations of each ion varied widely in both races, and were unrelated to race. Concentrations of Na+ and Cl? generally are somewhat higher in hand sweat than in body sweat; concentrations of K+ are much higher. It follows that the values for concentration of Na+ and Cl? reported in Table 3 probably are somewhat higher than would have been found in body sweat, and concentrations of K+ are probably much higher.  相似文献   
569.
Adult male Swiss-Webster (NIH) mice were isolated for 6 weeks. Aggressive behavior was tested on 2 occasions, 24 hours apart. Immediately following the 2nd test period, aggressors and isolated non-aggressors (controls) were decapitated and α-MSH concentration was measured in discrete areas of the brain. Only the nucleus accumbens and preoptic lateralis of the aggressors, showed a higher level of α-MSH when compared to the controls. The significance of these changes is discussed.  相似文献   
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