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21.
The experiment was conducted to investigate the human thermoregulatory responses during rest, exercise and recovery atT
a 20°C and 60% R.H. under the conditions of wearing two different types of clothing. Six healthy men wore two types of clothing: one covering the whole body area except the head (Type A, weight 1656 g), and the other covering only the trunk, upper arms and thighs (Type B, weight 996 g). The level of rectal temperature was kept significantly higher in Type B than in Type A during rest and recovery. The increased and decreased rates of rectal temperature during exercise and recovery were significantly greater in Type A than in Type B, respectively. These findings are discussed from the viewpoint of the differences of skin temperatures of the extremities between Type A and Type B. 相似文献
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23.
本文对洈水水库鳡鱼的生长及其利用进行了分析研究,结果表明:1.该种鱼生长快,高速生长时间长,可连续5年每年生长6kg以上;2.雌、雄鱼体长与体重生长分别适合Von.Bertalanffy的生长公式:L=L_∞(1-e-k(t-t·))和W=W_∞(1-e-k(t-t·))~3;3.雌鱼体重生长速度快于雄鱼,体长生长无明显差别;4.建议大中型水体中的鳡鱼与其它鱼类群落体重之比控制在3—5%为宜。 相似文献
24.
本文对洈水水库鳡鱼的生长及其利用进行了分析研究,结果表明:1.该种鱼生长快,高速生长时间长,可连续5年每年生长6kg以上;2.雌、雄鱼体长与体重生长分别适合Von.Bertalanffy的生长公式:L=L_∞(1-e-k(t-t·))和W=W_∞(1-e-k(t-t·))~3;3.雌鱼体重生长速度快于雄鱼,体长生长无明显差别;4.建议大中型水体中的鳡鱼与其它鱼类群落体重之比控制在3—5%为宜。 相似文献
25.
Strain-dependent expression of VH gene families 总被引:12,自引:0,他引:12
H D Jeong J L Komisar E Kraig J M Teale 《Journal of immunology (Baltimore, Md. : 1950)》1988,140(7):2436-2441
The tremendous diversity of the antibody specificity repertoire stems from the ability of each developing B cell to select one out of many possible variable, diversity, and joining gene segments by specific rearrangement of the DNA. The mechanism by which V region gene segments is selected is not known. Moreover, evidence for both random and nonrandom expression of VH genes in mature B cells has been presented previously. In this report, the technique of in situ hybridization is used to accurately measure at the single cell level VH gene family expression in LPS-induced cells from several strains. In this way, at least one-third of the B cells are stimulated and a large sampling of activated splenocytes from each strain analyzed. The use of in situ hybridization eliminates any potential biases resulting from transformation protocols. In addition, because all populations of cells are analyzed by both in situ hybridization and immunocytochemical staining with anti-IgM, the proportion of cells detected by in situ hybridization could be compared with the proportion of B cells, blasts, and plasma cells in the population. It was concluded from these comparisons that the cells being detected by in situ hybridization under the conditions described are plasmablasts and plasma cells. Therefore, an accurate measure of the functional and expressed VH gene repertoire could be made. The results clearly demonstrate strain-dependent variation in VH gene family expression, particularly VH 7183 and VH J558 with up to three-fold differences observed. Thus, either there is considerable strain variation in the number of functional VH gene family segments or the expression of VH genes is not entirely random. 相似文献
26.
限制性内切酶诱发的姊妹染色单体互换 总被引:1,自引:1,他引:0
用限制性内切酶PstⅠ,SalⅠ,PvuⅡ和BamHⅠ处理CHO细胞后,发现其SCE率升高,与对照相比,前三种酶具有显著性差异。但这些酶诱导SCE的效应与其致染色体畸变效应相比则较弱,提示引起DNA双链断裂的限制性内切酶不是SCE的强刺激物。实验结果表明,BrdU取代胸苷不能消除限制酶对底物DNA的识别及裂解。 相似文献
27.
天名精倍半萜内酯化合物 总被引:2,自引:0,他引:2
从菊科天名精全草中分得天名精内酯酮,特勒内酯,11(13)-二氢特勒内酯和异埃瓦内酯。其中11(13)-二氢特勒内酯和异埃瓦内酯为新的天然产物。 相似文献
28.
29.
猪肺炎支原体膜上ATP酶为Mg~(2+)激活,乌巴因不抑制。DCCD和寡霉素对该酶也无抑制作用,只有NBD与Quercetin才有一定的抑制效果。用梯度凝胶电泳可获均一的具有活性的酶蛋白带。 相似文献
30.
Dr. Jian Wen Chen Lanping Zhang Jiantao Song Fen Hwang Qinghua Dong Jian Liu Yumin Qian 《Current microbiology》1992,24(4):189-192
The glycoproteins and glycolipids from membranes of virulent strain Z and avirulent strain M ofMycoplasma hyopneumoniae have been compared. The proteins and the glycoproteins were identified by SDS-polyacrylamide gel electrophoresis and concanavalin A-biotin labeling, respectively. The membrane preparation contained approximately 34 protein bands with molecular weights between 20 KD and 100 KD. The concanavalin A-biotin system reacted with a glycoprotein of a molecular weight of approximately 28,000 from avirulent strain M and did not react with the correspondent band from virulent strain Z. The membrane glycolipids of both strains consisted of monogalactosyldiacylglycerol (MGDG) and digalactosyldiacylglycerol (DGDG), and the percentages of 160, 180, and 181 fatty acids comprised more than 80% of the total fatty acids of membrane glycolipids. The 180 fatty acid of MGDG in avirulent strain M was twofold higher than that of virulent strain Z. 相似文献