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921.
Male Kazak sheep and Xinjiang fine wool sheep, six for each different age group (days 2, 30, 60, 90 and 120), were used in the present study to investigate the tissue distribution and developmental changes of ghrelin mRNA expression in abomasum; however, there was no 120-day-old Kazak sheep. After measurement of body weight, the tissues such as hypothalamus, pituitary, heart, liver, rumen, reticulum, omasum, abomasum, duodenum, and longissimus dorsi muscle were sampled. And the total RNA of different tissues was extracted to determine the abundance of ghrelin mRNA by RT-PCR and real-time PCR. The results showed that (1) for both breeds, body weight among different ages was significantly different (P<0.05). And from day 30 to 90, the body weight of Kazak was significantly higher than that of Xinjiang (P<0.01); (2) Ghrelin mRNA existed in all the above tissues and was significantly higher in the abomasum than in other tissues (P<0.05); (3) the temporal patterns of abomasum ghrelin mRNA expression in Kazak and Xinjiang were similar. From day 2 to 60 in Kazak and 2 to 90 in Xinjiang, there was a steady increase in the ghrelin mRNA level. By day 60 in Kazak and day 90 in Xinjiang, the level reached a plateau and remained steady. These results also demonstrated that from birth to day 90, ghrelin mRNA level was significantly higher in Kazak than in Xinjiang (P<0.01).  相似文献   
922.
野生稻高产QTL高效表达的光合生理基础   总被引:2,自引:1,他引:1  
以携带野生稻高产QTL的晚稻新恢复系远恢611所配部分强优势组合为材料,对其部分光合生理指标进行测定的结果表明,远恢611系列组合杂种优势强,穗大粒多,库容量大,具有超高产潜力;后期上面3片功能叶宽大、直立、叶面积大,与茎秆夹角小,不披垂;比叶重大而稳定,不早衰;剑叶净光合速率高,库很大且源较足是远恢611系列组合高产的主要生理原因;也可能是野生稻高产QTL高效表达的重要生理基础。  相似文献   
923.
Synthetic pyrethroids are considered as possible sub-stitutesfor some organophosphate carbamates or organochlo-rine insecticides,and have been used extensivelyfor morethantwo decades[1].Pyrethroids are preferred over otherinsecticides because of their easy degradation into non-toxic or less toxic metabolites under natural conditions.Consequently,there has recently beena dramatic increaseinthe use of pyrethroid pesticides to control insect pests.However,synthetic pyrethroids were also reported …  相似文献   
924.
Unionidae(Bivalvia)are distributed infreshwaters,and represent a significanttaxonof benthic community[1].In China,freshwater mussels are abundant resources[2].Since1949,substantial investigations onthe unionidfau-na had been undertakenin China[3—8].Withreference tooverseas research[9,10],a preliminary reorganization onthe Unionidae was performed accordingtosome classifica-tion characteristics such as shell shape,larvae character-istics,and breeding habit[11].Due tothe serious conver-gence of freshwater muss...  相似文献   
925.
With the development of modern agriculture,envi-ronmental contamination by a variety of organic toxicagents has been detected in many freshwater systems.These include herbicides,insecticides,surfactants andother organic compounds,which have,been reported byStratton[1]and many other authors to affect boththeir tar-get and non-target organisms whenever dischargedintotheenvironment,thus impairing heavily on the structure andfunction of ecosystems.Therefore,it is necessary to de-velop pesticides w…  相似文献   
926.
冷激处理对油桃贮藏品质和抗氧化酶活性的影响   总被引:19,自引:5,他引:14  
以‘秦光2号’油桃为材料。研究了冷激处理对果实冷藏中品质及相关酶活性的影响。结果表明,0℃冷空气.处理3.5h可明显延迟油桃的后熟衰老;同时有推迟乙烯释放高峰和呼吸高峰。提高膜脂过氧化保护酶SOD、CAT、POD的活性,保持果肉硬度。减轻冷害发生的作用。但对可溶性固形物和可滴定酸含量无明显影响。  相似文献   
927.
LY-04 and WSQIF are newly-synthesized compounds which were presented by the Institute of Pesticides Chemistry, Central China Normal University. LY-04 belongs to α-oxophosphonic acid derivatives, while WSQIF is an aromatic acetyl oxophospho04 and WSQIF were determined in S. obliquus cells at 24h, 48h, 72h, 96h represented by cell density. Our data showed that the 24h, 48h, 72h, 96h EC50 of LY-04 were 1983mg/L, 2943mg/L, 240mg/L and 65.0mg/L acetone, respectively, and the 24h,48h, 72h, 96h EC50 of WSQIF were 15.9mg/L, 53.0mg/L, 98.0mg/L and 28.8mg/L respectively. LY-04 displayed a higher insecticidal activity, while WSQIF showed a higher phytocidal activity. As LY-04 and WSQIF were designed to act as insecticide and herbicide, respectively, the results were in contrast to the anticipated ones. According to the toxicant classification standard,EC50 of both substances was far higher than 3mg/L, while the toxicity of LY-04 and WSQIF to aquatic algae were fairly low, indicating that these two pesticides are rather safe to the aquatic ecosystem.  相似文献   
928.
珍稀濒危植物组织培养研究进展   总被引:3,自引:0,他引:3  
本文总结了我国一、二级保护植物的组织培养研究现状,分析了已有组织培养报道的珍稀植物在外植体选择和分化途径上的特点,并从基本培养基、激素及附加营养成分等方面分析了珍稀植物组织培养的影响因素;提出了在珍稀濒危植物组织培养研究和实际应用中存在的问题.  相似文献   
929.
对2002~2004年唐家河自然保护区周边林缘社区4个村与野生动物产生冲突进行调查分析,发现野生动物主要对农作物、林果和家畜家禽造成危害。其主要原因是狩猎活动减少、退耕还林后,野生动物数量逐年增多、活动范围扩大,林缘社区出现自然减员现象,传统防范难见成效。提出解决人与野生动物矛盾和冲突的对策是实施移民、调整种植结构、建立生态旅游小区提高村民的经济收入、发展特色经济。  相似文献   
930.
对广西12株狂犬病病毒株g基因全序列进行测序分析,结果显示:广西毒株属于I型,可分为3个群,即Ⅰ群、Ⅱ群和Ⅲ群。GX01、GX08、GX09、GX014、GX091、GX195、GX260、GXLA8株为Ⅰ群,GX219、GX074、GXBM3株为Ⅱ群,GXN119株为Ⅲ群。Ⅰ群的广西毒株g基因核苷酸的同源性为97.6%~99.9%,氨基酸同源性在97.7%~100%之间;Ⅱ群的核苷酸的同源性为98.2%~99.0%,氨基酸的同源性在98.5%~99.2%之间。糖蛋白在主要的抗原位点GI、GⅡ区以及与中和抗原有关的36、263、367位氨基酸没有变异,GⅢ区上只有Ⅱ群在332位缬氨酸变异为异亮氨酸,G蛋白上的氨基酸主要在-2、-5、-13、-14、-15、-16、90、96、132、140、156、168、170、204、241、249、253、264、289、332、382、427、436、445、463、474位共26个氨基酸发生了变异,这些氨基酸的变异具有群的特异性。  相似文献   
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