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971.
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976.
三峡库区有丰富的植物资源。据资料统计表明:库区有维管束植物6088种,分属于208科,1428属,约占全国植物总数的20%左右;有珍稀植物57种,占全国珍稀植物的14.7%。库区有植被类型78个,有药用植物3500种,隶属于603属,174科,同时有丰富的粮食经济植物和野生香料植物资源.随着三峡工程的修建,直接或间接地破坏了植物的生存环境,因此,加强法制宣传教育,提高环境保护意识.建立自然保护区和植物园等措施,有效的保护了库区植物资源,改善了生态环境的质量,促进了人与自然的和谐发展。 相似文献
977.
Suicide and Social Change in China 总被引:7,自引:0,他引:7
Using recently available data from China's Disease Surveillance Points system, we estimate that there are over 300,000 suicides in China per year; this makes suicide one of the most important causes of death in the country and makes the suicide rate in China one of the highest in the world. Moreover, the pattern of suicides in China is quite different than in other parts of the world – there are more completed suicides among females than males and rural rates are three-fold urban rates. The lack of reliable suicide data prior to 1987 makes it difficult to determine whether the rates are currently rising, falling, or staying constant. However, reports of suicides in the Chinese press and case studies conducted by the authors suggest (but do not prove) that the high rates of suicide currently experienced are related to the social changes that have occurred with the economic reforms (which started in 1978). Another possible explanation for the high rates of suicide is the large numbers of persons with depressive illness in China who remain untreated. Single-cause models of suicide (i.e., social factors or mental illness) do not do justice to the complexity of the processes involved and, therefore, do not provide useful information about the etiology and prevention of suicide in China or elsewhere. We describe our own dynamic model of suicide that includes five interacting factors which, we believe, collectively determine the suicide rates in a community. 相似文献
978.
14-3-3 proteins are intracellular, dimeric molecules that bind to and modify the activity of several signaling proteins. We used human 14-3-3zeta as a bait in the yeast two-hybrid system to screen a murine embryonic cDNA library. One interacting clone was found to encode the carboxyl terminus of a putative protein kinase. The coding sequence of the human form (protein kinase Ualpha, PKUalpha) of this protein kinase was found in GenBank(TM) on the basis of sequence homology. The two-hybrid clone was also highly homologous to TOUSLED, an Arabidopsis thaliana protein kinase that is required for normal flower and leaf development. PKUalpha has been found by coimmunoprecipitation to bind to 14-3-3zeta in vivo. Our confocal laser immunofluorescence microscopic experiments revealed that PKUalpha colocalizes with the cytoplasmic intermediate filament system of cultured fibroblasts in the G(1) phase of the cell cycle. PKUalpha is found in the perinuclear area of S phase cells and in the nucleus of late G(2) cells. Transfection of cells with a dominant negative form of 14-3-3eta promotes the nuclear localization of PKUalpha. These results suggest that the subcellular localization of PKUalpha is regulated, at least in part, by its association with 14-3-3. 相似文献
979.
980.
马立克氏病病毒REispens株B抗原基因的克隆及其重组鸡痘病毒的构建 总被引:1,自引:0,他引:1
Purified DNAs from Chicken Embryo Fibroblast (CEF) cultures infected with MDV strain Rispens were used as templates. Specific fragment with the size of about 2.9 kb was successfully amplified through Polymerase Chain Reaction(PCR) and identified to be gB gene of MDV by dot blot hybridization with a digoxigenin-labelled MDV gB specific oligonucleotide probe. The gB gene from strain Rispens was cloned into pUC19 and FPV insertion vector pFG1175-1 to construct plasmid pMGB and pFGBR1775-1 respectively. DOSPER liposome-mediated transfection with insertion vector DNA pFGBR1175-1 was performed on CEF monolayers infected with FPV 3-4 h earlier. Recombinant FPV was clone purified. Immunofluorescence Assay(IFA) showed that MDV gB gene had been expressed in FPV. 相似文献