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取食雄蜂蛹粉对龟纹瓢虫和异色瓢虫卵黄发生的影响 总被引:1,自引:1,他引:0
本文比较了龟纹瓢虫Proylea japonica和异色瓢虫Harmonia axyridis取食蚜虫和取食雄蜂蛹粉时的卵黄发生情况.当取食雄蜂蛹粉时,体内卵黄蛋白出现迟,积累速度慢,产卵前期长.但用保幼激素类似物ZR512点滴处理后则能达到与食蚜对照相当的水平.ZR512对取食雄蜂蛹粉瓢虫的作用显著大于取食岈虫者.进一步的研究表明,ZR512能促进这两种瓢虫取食雄蜂蛹粉,但对成虫的体重没有明显的影响.因此推论,雄蜂蛹粉基本能够满足这两种瓢虫生殖的营养需要,但对其内分泌有一定的影响,使瓢虫处于类似生殖滞育的状态.本文根据不同食物条件对卵黄蛋白发生的影响不同,建议用卵黄蛋白的量作为生理指标,以快速初步筛选和评估人工饲料. 相似文献
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A series of 52 young male white laboratory mice were starved for a maximum of five days, and 45 normally fed animals were used as controls. A group of experimental animals and a corresponding control group were sacrificed after two, three, and four days' starvation and after six, 12 and 17 days' refeeding. Even after two days the animals had lost weight, and the liver cells had diminished highly significantly. A return to the initial values was noted after 12 days' refeeding. In the experimental animals a strong negative correlation was noted between the cell count per field and body weight (r =–0.712, b =–7.520), while no such correlation was observed for the controls. The volume of the liver cells was reduced by 61.7 %, the volume of their nuclei by 16.2 % after four days' starvation. After two to three days' starvation the liver cells often showed a slight accumulation of fat. Mitoses were frequent in the liver cells during the stage of regeneration, when the cells had attained the same size as in the controls. 相似文献
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The kidney fat was histologically examined of 27 spontaneously dead lambs of which 14 had starved. The lambs were born with mature fat, but in young animals a starvation period of more than 24 hrs. reduced the fat tissues and changed its cells towards the embryonal type built up of preadipocytes. These cells were smaller than the mature fat cells. Nucleus was large, round and situated in the centre of the cell. The slight eosinophilic, strongly diminished cytoplasm was some granulated and had some small fat droplets. The starvation changes of fat cells did not depend on the weight of animals or on the age of lambs less than two weeks. 相似文献
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本工作应用心钠素放射免疫测定和分子杂交技术首次发现,吗啡耐受大鼠血浆心钠素水平显著降低,心房内心钠素含量明显升高,同时心房内心钠素特异性mRNA水平也相应提高,提示在吗啡耐受时大鼠心房内心钠素的合成和贮存增加,释放减少。 相似文献
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肝再生的调控及原癌基因表达 总被引:4,自引:0,他引:4
肝脏再生过程中受到多种体液因素的调控。肝细胞生长因子(HGF)、肝刺激因子(HSS)等对肝细胞有促分裂作用;转化生长因子β1(TGFβ1)等则具有抑制作用。此外,肝再生还需要去甲肾上腺素(NE)、胰岛素等辅助分裂原的存在,共同调节肝再生。肝细胞分裂增殖与原癌基因表达密切相关。肝细胞从静息期进入细胞周期,以及在整个细胞周期中,某些原癌基因有特征性的表达。 相似文献
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皖南汉族的趾纹研究 总被引:3,自引:0,他引:3
本文对皖南地区520例汉族大学生的趾纹进行了调查分析,计算出了各型趾纹频率、趾纹组合、趾嵴纹计数等项参数。比较了不同性别、不同侧别和不同人种间的差异,分析了趾纹类型和趾嵴纹计数在各趾的分布特点,并对差异的原因进行了讨论。Abstract: The authors inverstigated and analysed the toe prints of 520 cases of good healthy students in Wannan area of Aahui, and calculated the frequency of various toe patterns, combinations of toe patterns, toe ridge counts (TRC) and so on. The differences between sexes, sides and reces were compared. The distributive character of toe patterns and toe ridge count on every toe were analysed. The different cause were discussed. 相似文献
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On semiparametric inference for modulated renewal processes 总被引:1,自引:0,他引:1