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131.
应用PCR技术检测细小病毒H-1DNA在人肝癌与裸鼠正常组织中复制的差异黄青山,马承武,郭兰萍,陈献华,罗祖玉(上海复旦大学生理与生物物理学系,上海200433)关键词:自主性细小病毒H-1及MVM,聚合酶链式反应(PCR),人肝癌模型,抑瘤作用,肿...  相似文献   
132.
本文用一氧化氮合酶(NOS)的组织化学方法对胎龄15周至36周的人胎视网膜含NOS神经元的发育进行了研究。胚胎15周视网膜颞侧半少部分神经元即有NOS的表达,20周视网膜含NOS神经元数密度达峰值。大部分含NOS神经元胞体位于内核层内带,只少部分位于节细胞层,其突起均分布于内同层,形成内同层的1、3、5亚层。含NOS神经元的形态各异,依据其突起的多少分Ⅰ、Ⅱ、Ⅲ等三种类型,其中Ⅱ、Ⅲ型含NOS神经元在28周以后才开始出现,且愈近晚期胎龄,它们所占含NOS神经元的数量比呈上升趋势。随视网膜发育成熟,含NOS神经元胞体均面积呈不断增大的变化。本文结果显示:人胎视网膜内核层含NOS神经元为无长突细胞,节细胞层的Ⅰ型含NOS神经元为移位无长突细胞,推测它们在视网膜的发育过程中对内网层突触的形成与修饰可能起有重要作用。  相似文献   
133.
用HBsAgRPHA做为模式,选用羊、火鸡、鹅、人O型血球为载体,醛化后分成致敏和不致敏两种,与异嗜性抗体、中国生物制品药品检定所的参比品等作凝集试验。结果表明,无论特异性还是灵敏度都以人O型血球为最佳。在此基础上,设计了五种醛化方法处理人O型血球,共得出18个醛化样品,经73种不同的比较试验,筛选出最佳醛化方法为改良丙酮醛──甲醛法,采用该法醛化后血球为褐色,阴性血清和空白对照背景清晰,血球沉集点致密,下滑程度好。致敏抗—HBsMcAb后,使HBsAg灵敏度达到1~2ng/ml。为制备高质量的血凝试剂提供了最佳载体。  相似文献   
134.
通过DNA体外重组技术,以pET-3b为表达载体,构建了重组表达质粒pET-6R(B)和PET-6R(B)4,分别编码28kD的hIL-6R配基结合区片段及其53kD的二联体蛋白,并为酶切分析和DNA序列分析所证实。SDS-PAGE分析表明,含有重组表达质粒的菌株可分别表达出28kD的蛋白rIL6R-28和53kD的rIL6R-53。重组蛋白分别占菌体总蛋白的45%和29%左右。重组蛋白主要以包涵体形式存在,Western印迹表明重组蛋白具有IL-6R的抗原性。  相似文献   
135.
以人胃癌细胞BGC-823为模型,研究了毛喉萜(forskolin)对胃癌细胞中蛋白激酶C活性及其亚类基因表达的作用,同时也观察了毛喉萜对癌基因c-jun及抑癌基因p53表达的影响.结果表明,2×10~(-5)mol/L毛喉萜处理BGC-823细胞72h,细胞质、膜和细胞核PKC活性下降,PKC亚类β,γ基因表达被抑制,癌基因c-jun的表达也明显降低,而抑癌基因p53表达升高,上述变化可能是毛喉萜抑制胃癌细胞增殖等生理效应的重要分子事件。  相似文献   
136.
将编码人单核细胞趋化蛋白-1(MCP-1)的基因亚克隆到大肠杆菌表达载体pEX31A中,在大肠杆菌中表达出MS2/MCP-1融合蛋0白,该表达产物约占菌体总蛋白的15%左右,Westernblot检测表明,表达产物可与MCP-1抗体特异反应。采用琼脂糖平板法进行活性测定表明,表达产物具有明显的单核细胞趋化活性,说明N端融合一段细菌蛋白对MCP-1有无趋化活性可能没有影响。  相似文献   
137.
t-PA cDNA在CHO细胞中的高效稳定表达   总被引:1,自引:0,他引:1  
我们曾报道t-PA mRNA非翻译区序列对其表达有明显的抑制作用,在此基础上,通过对5′-UTR及3′-UTR的改造,使t-PA在COS-7细胞中的表达水平提高30倍左右。将t-PA表达质粒用电击法转染中国仓鼠卵巢细胞二氢叶酸还原酶缺陷株(CHO-dhfr),经过混合加压及筛选,在CHO细胞中高效表达了t-PA,表达水平达到5000~6000 IU/10~6细胞/24hr。重组t-PA具有与天然t-PA相同的分子量及酶活性。经过8个月连续传代,表达水平未下降,表明细胞株是稳定的,其主要指标均符合工程细胞株的要求。  相似文献   
138.
Our objective is to test an optimality model of human fertility that specifies the behavioral requirements for fitness maximization in order (a) to determine whether current behavior does maximize fitness and, if not, (b) to use the specific nature of the behavioral deviations from fitness maximization towards the development of models of evolved proximate mechanisms that may have maximized fitness in the past but lead to deviations under present conditions. To test the model we use data from a representative sample of 7,107 men living in Albuquerque, New Mexico, between 1990 and 1993. The model we test proposes that low fertility in modern settings maximizes number of grandchildren as a result of a trade-off between parental fertility and next generation fertility. Results do not show the optimization, although the data do reveal a trade-off between parental fertility and offspring education and income. We propose that two characteristics of modern economies have led to a period of sustained fertility reduction and to a corresponding lack of association between income and fertility. The first is the direct link between costs of investment and wage rates due to the forces of supply and demand for labor in competitive economies. The second is the increasing emphasis on cumulative knowledge, skills, and technologies in the production of resources. Together they produce historically novel conditions. These two features of modern economies may interact with evolved psychological and physiological mechanisms governing fertility and parental investment to produce behavior that maximizes the economic productivity of lineages at the expense of fitness. If cognitive processes evolved to track diminishing returns to parental investment and if physiological processes evolved to regulate fertility in response to nutritional state and patterns of breast feeding, we might expect non-adaptive responses when returns from parental investment do not diminish until extremely high levels are reached. With high economic payoffs from parental investment, people have begun to exercise cognitive regulation of fertility through contraception and family planning practices. Those cognitive processes maynot have evolved to handle fitness trade-offs between fertility and parental investment. A preliminary presentation of this data was published in R. I. M. Dunbar, ed.,Human Reproduction Decisions: Biological and Social Perspectives. New York: St. Martin’s Press, 1995. Support for the research project, “Male Fertility and Parenting in New Mexico,” began with two seed grants from the University of New Mexico’s Biomedical Research Grants Program, 1988 and 1989, and one from the University of New Mexico Research Allocations Committee, 1988. Further seed money as well as interim funding came from the William T. Grant Foundation (#89130589 and #91130501). The major support for the project came from the National Science Foundation from 1990 to 1993 (#BNS-9011723 and #DBS-911552). Both National Science Foundation grants included Research Experience for Undergraduates supplements. Hillard S. Kaplan is an Associate Professor of Anthropology at the University of New Mexico. His earlier research and publications focused on food sharing, time allocation, parental investment, and reproductive strategies among Ache hunter-gatherers in Paraguay, Machiguenga and Piro forager-horticulturalists in Peru, and villagers of several ethnicities in Botswana. New research and theory concern fertility, parental investment, and mating strategies in developed and developing nations. This research formulates a new theory of reproductive decision-making and the demographic transition, integrating human capital and parental investment theory in a synthesis of economic and evolutionary approaches. Jane B. Lancaster is a Professor of Anthropology at the University of New Mexico. Her research and publications are on human reproductive biology and behavior, especially human parental investment; women’s reproductive biology of pregnancy, lactation, and child-spacing; and male fertility and investment in children. Current research with Hillard S. Kaplan is on male life history strategies among a large sample of men in New Mexico. She has coedited three books on human parental investment:School-Age Pregnancy and Parenthood (with B. Hamburg),Parenting across the Life Span (with J. Altmann, A. Rossi, and L. Sherrod), andOffspring Abuse and Neglect (with R. Gelles). She is scientific editor of a quarterly journal,Human Nature: An Interdisciplinary, Biosocial Perspective published by Aldine de Gruyter. She is also a council member of the newly formed Human Behavior and Evolution Society. John A. Bock is Andrew W. Mellon Post-Doctoral Fellow in Epidemiology and Population Health at the National Centre for Epidemiology and Population Health, The Australian National University. His research focuses on the allocation of parental investment and the determinants of children’s activities, integrating aspects of economic and evolutionary theory. He has ongoing field research with Bantu and Bushmen agro-pastoralists and forager-horticulturalists in the Okavango Delta, Botswana. He is also collaborating with Lancaster and Kaplan on the determinants of progeny distribution and homosexuality among New Mexican men. Sara E. Johnson is a Ph.D. candidate at the University of New Mexico. Her major research trajectory focuses on trade-offs in life history characters. Her research experience includes participation in a study of variation in growth and development among children in a multi-ethnic community in the Okavango Delta, Botswana, in addition to her dissertation work on individual variation in growth and mortality among juvenile baboons. She is collaborating with Lancaster and Kaplan on the association between survival and fertility among Albuquerque men.  相似文献   
139.
ABSTRACT. Microsporidian spores were developed from cells which were grown in vitro from a human liver lesion which was due to larval Echinococcus multilocularis . The microsporidian spores developed in the same fashion as an Encephalitozoon cuniculi . The Encephalitozoon -like spores were completely separated on Percoll gradients. The separated spores contained DNA capable of amplification by two different primer sets designed for the polymerase chain reaction (PCR) of E. multilocularis DNA. However, the cell DNA from which microsporidium developed was thoroughly insensitive to the PCR using the E. multilocularis primer sets. The results strongly suggested that Encephalitozoon should be taken into consideration, when DNA isolated from larval E. multilocularis is analyzed.  相似文献   
140.
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