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51.
研究了黑杨(Populus nigra)萎蔫枝叶及其气味对棉铃虫成虫的隐藏部位、产卵部位、交配率及产卵量等的影响,并对黑杨萎蔫枝把在田间诱集到的棉铃虫雌蛾进行了解剖观察。结果表明,在田间,黑杨萎蔫枝把诱集到的棉铃虫93.3%已经交配。在气候箱中,放置黑杨萎蔫枝叶的环境中配对饲养的棉铃虫,经过1个暗期和2个暗期后,其交配率与对照环境中的均无显著差异。在光期开始时,有51.5%的成虫隐藏在饲养笼内所设置的黑杨叶子圆片下,对照纱布圆片下仅有16.7%。叶子圆片所在区域的日平均落卵量显著大于对照区。黑杨萎蔫枝叶及其气味对棉铃虫的产卵前期、产卵持续期、成虫寿命和产下50%的卵所用的时间无显著影响,但饲养笼内有黑杨枝把或黑杨叶片气味存在时,棉铃虫的产卵量比模拟枝把和对照显著提高。 相似文献
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盐池半荒漠风沙区土地沙漠化发生发展规律的研究 总被引:1,自引:0,他引:1
本文耐盐池半荒漠风沙区土地沙漠化发生发展规律进行了探讨,主要分析了在土地沙漠化的过程中土壤和植被的变化过程及其成因。 相似文献
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AIM: To explore interaction and biological behaviour changes of two kinds of cells-blastocysts and hepatocarcinoma cells in the same microenvironment. METHODS:The models of mouse blastocysts co-cultured with human hepatocarcinoma cell lines were established, then biological behaviours and mutual effects of the two kinds of cells in co-culture system were observed. RESULTS: Compared with control group, hepatocarcinoma cells with differently invasive and metastatic potential significantly enhanced the rates of blastocyst hatchment , attachment and outgrowth(P<0.05). There was no significant difference in those among hepatocarcinoma cells co-cultured groups (P>0.05). The blastocyst hatched and attached to hepatocarcinoma cells with differently invasive and metastatic potential. Then, differential trophoblasts invaded hepatocarcinoma cells. The clear-cut interfaces were gradually formed between both sides. Hepatocarcinoma cells on interface showed changes of growth direction and cell shapes and did not invade blastocysts. CONCLUSIONS: Hepatocarcinoma cells promoted blastocyst development. Blastocysts implanted and invaded hepatocarcinoma cells with differently invasive and metastatic potential in vitro, which indicate that blastocyst implantation in vitro does not relate with the kinds and differential level of interactional cells and the low selectivity maybe relate with high adaptability of early life. 相似文献
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AIM: To investigate the role of nitric oxide synthase (NOS), soluble guanylyl cyclase (sGC) and protein kinase C (PKC) signaling in tumor necrosis factor-α (TNF-α)-induced cardioprotection against hypoxia/reoxygenation (H/R) injury. METHODS: Neonatal rat ventricular myocytes were pretreated with TNF-α or sodium nitroprusside (SNP) or L-arginine (L-Arg), respectively, for 12 h and then subjected to continuous hypoxia for 12 h, followed by reoxygenation for 6 h. The manganese superoxide dismutase (Mn-SOD) activity of the cells was measured after H/R. Myocyte injury was determined by the release of lactic dehydrogenase (LDH). RESULTS: TNF-α (105 U/L) significantly increased the Mn-SOD activity and decreased release of LDH from ventricular myocytes. The cardioprotection against H/R injury was induced by the pretreatment with SNP (5 μmol/L) or L-Arg (5 mmol/L), which was blocked by ODQ (10 μmol/L), the specific sGC inhibitor, and Chel (5 μmol/L), the specific PKC inhibitor. Pretreatment with L-NAME (100 μmol/L), ODQ, Chel, antoxidant 2-MPG (400 μmol/L) or tyrosine kinase inhibitor genistein (50 μmol/L) attenuated the increased Mn-SOD activity and reduced LDH level induced by TNF-α. CONCLUSION: The results suggest that NO may play a role in TNF-α-induced cardioprotection, which is mediated by sGC and PKC. 相似文献