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1.
人Ⅱ型囊泡单胺转运体基因的克隆 总被引:3,自引:0,他引:3
目的 为获得人Ⅱ型囊泡单胞转运体(vesicular monomine transporter-2VMAT2)以治疗帕金森病,克隆添加Kozak序列的VMAT2cDNA,用于真核细胞表达。方法 从人胎脑中提取总RNA,逆转录成cDNA,设计一对引物用PCR方法扩增目的cDNA片段并将其重级一起pGEM-Easy-T载体中,酶切鉴定插入片段后,进行全序列测定。结果 RT-PCR扩增到1637bp的带有Kozak序列的cDNA片段。结论 克隆人VMAT2cDNA片断,可用于真核细胞表达。 相似文献
2.
While the hypothalamo-pituitary-adrenocortical (HPA) response to stress appears to be conserved in vertebrates, the manner in which it is activated and its actions vary. We examine two trends in the stress biology literature that have been addressed in amphibian and reptilian species: (1). variable interactions among stress, corticosterone, and reproduction and (2). adrenocortical modulation. In the first topic we examine context-dependent interactions among stress, corticosterone, and reproduction. An increasing number of studies report positive associations between reproduction and corticosterone that contradict the generalization that stress inhibits reproduction. Moderately elevated levels of stress hormones appear to facilitate reproduction by mobilizing energy stores. In contrast, pronounced activation of the HPA axis and extremely elevated levels of stress hormones appear to inhibit reproduction. Much of these contrasting effects of stress and reproduction can be explained by expanding the Energetics-Hormone Vocalization Model, proposed for anuran calling behavior, to other taxa. In the second topic, a number of amphibians and reptiles modulate their HPA stress response. Adrenocortical modulation can occur at multiple levels and due to a variety of factors. However, we have little information as to the physiological basis for the variability. We suggest that several ecologically based ideas, such as variability in the length of the breeding season and lifetime reproductive opportunities, can be used to explain the utility of adrenocortical modulation in these taxa. 相似文献
3.
本文作者采用基因克隆手段,以pAt153为载体,从一份山西襄坦宫颈癌高发区宫颈癌患者的手术标本中,成功地克隆到2株与HPV16同源的基因片段。经PstI、KpnI、TaqvI、PvuII等16种限制性内切酶酶谱分析及其部分基因序列的鉴定,证明这是在国内首次克姓到一株分子量约为8.0kb完整的HPV16型全序列DNA及一株分子量为5.4kb的HPV6基因片段。经实验证明:该基因片段E6、E7及部分LI基因丢失,在750单核苷酸处发生变异,产生一新的BamHI酶切位点。该完整的HPV16基因组被命名为HPV16Z,HPV16基因片段被命名为HPV16F。用新分离到的HPV16Z作分子探针,检测襄坦337份宫颈癌及阴道活检标本的HPV16型同源序列的结果显示,慢性阴道炎阳性率为17.28%(14/81);宫颈炎为11.89%(17/143);宫颈癌前病变46.81%(22/47);宫颈癌为72.73%(48/66)。证明山西宫颈癌高发区宫颈癌前病变及宫颈癌组织中主要为HPV16Z感染。 相似文献
4.
分泌型重组人生长激素的研制 总被引:3,自引:2,他引:3
从人脑垂体组织中克隆了人生长激素基因并构建了分泌型表达基因工程菌E.coliK802/pAVGH。研制的rhGH中试产品,各项技术指标均达到临床应用要求 相似文献
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Perinatal administration of the endocrine disruptor bisphenol A (BPA) reportedly inhibits the sexual behavior of sexually naïve adult male rats. In order to evaluate the effects of BPA administration during early development on later reproductive behavior, we administered one of five doses of bisphenol A daily to pregnant female rats throughout gestation and lactation, and quantified the appetitive and consummatory sexual behaviors of the resultant male and female offspring over multiple sexual encounters in adulthood. Males receiving low dose perinatal BPA (50 μg/kg bw/day) showed persistent deficits in sexual behavior in adulthood. Males receiving the highest dose (5 mg/kg bw/day), however, were indistinguishable from controls with respect to consummatory sexual behaviors but showed decreased latencies to engage in those behaviors when sexually naïve, with significant non-linear, or U-shaped, dose-response relationships observed on the first and last day of testing. Adult female sexual behavior was not affected by early BPA administration at any dose tested. These results are consistent with previous reports that BPA exerts behavioral effects especially at low doses, and further indicates that BPA can cause lasting impairment of sexual behavior in males, but does not alter the normal development of female appetitive or consummatory sexual behaviors. To our knowledge, this is the first report indicating that adult sexual performance is impaired in sexually experienced animals following perinatal exposure to bisphenol A. 相似文献
6.
Male desert locusts in the gregarious phase release phenylacetonitrile (PAN) on becoming sexually mature. It has been assumed that this chemical is responsible for aggregation of adult desert locusts. However, PAN has repellent characteristics and is involved in sexual behavior. Mature males release PAN as a volatile to serve as a kind of olfactory concealment during mating and to prevent competing males from homosexual encounters. We conclude that PAN is a courtship-inhibiting pheromone exclusively used under crowded conditions in dense populations when high sperm competition occurs among desert locust males. By chemically enhancing their mate guarding, gregarious males improve the protection of their mate from rivals and ensure their reproductive success. 相似文献
7.
大麻哈鱼基因文库的构建及其生长激素基因的克隆 总被引:4,自引:0,他引:4
本文主要论述了黑龙江省特有鱼种,大麻哈鱼全基因文库的构建方法以及从所构建的1.9×10~(?)噬菌体成斑单位/ugDNA基因文库中克隆出生长激素基因片段的研究结果,作者使用DM-BL3入噬菌为载体,将大麻哈鱼肝总DNA的15-20Kb片段重组到载体中,再包装成新的重组噬菌体,以含虹鳟鱼生长激素DNA部分序列的PAF51为探针,经[~(12)P]dCTP标记后,与噬菌斑杂交,自显影,获得3个阳性斑,复筛获得90%以上阳性斑,酶切回收生长激素基因片段,实验证明,已成功地获得大麻哈鱼生长激素基因片段,可供进一步亚克隆或转移研究使用。 相似文献
8.
犬瘟热病毒核衣壳蛋白基因片段的克隆和表达 总被引:6,自引:0,他引:6
目的 构建pMal N重组表达载体 ,转化E .coliDH5α ,诱导表达犬瘟热病毒 (CDV)重组核衣壳 (N)蛋白。方法 采用RT PCR技术 ,从CDVRNA中扩增编码N蛋白的基因片段 ,通过连接反应 ,构建重组克隆载体和重组表达载体 ,转化感受态。E .coliDH5α细胞。通过IPTG诱导表达CDV重组N蛋白。结果 扩增出约 1 7kbCDV全长的主要结构蛋白N蛋白基因 ,通过PCR获得 5 36bpN蛋白基因片段。将N蛋白基因片段克隆入原核表达载体pMal C2 ,表达产物麦芽糖结合蛋白 (MAP)与N蛋白的融合蛋白的相对分子质量约 6 0× 10 3,与预期大小一致。结论 构建的pMal N重组载体所表达的CDVN蛋白为进一步研究CDV的特异、敏感的抗体检测方法打下基础 相似文献
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Bradley J. Pusey 《Environmental Biology of Fishes》1990,29(1):15-26
Synopsis Changes in the age/length structure of Lepidogalaxias salamandroides populations in temporary waters of south-western Australia were monitored over a 51 month period by regular field sampling. Each year the study area experienced a summer drought of approximately five months duration. During the drought period Lepidogalaxias burrows into the mud and aestivates and substantial mortality occurs during this period. Body lipid reserves decrease during this period suggesting that they are the main energy source used during aestivation. The amount of lipid remaining after aestivation appears to be important in determining when female fish reproduce. Males die after reproduction and achieve a maximum age of only about 12 months. Some females also reproduce and die at this age while others defer reproduction for another year. Fecundity is much higher in these older, larger fish: they must however, survive two drought periods before they reproduce. The evolution of the life history style shown by Lepidogalaxias salamandroides is discussed with respect to the well defined seasonality of the region and it is suggested that selection for reproduction at an early age is balanced by the constraints of offspring survival during the aestivation period. 相似文献
11.
Mathers JC 《Genes & nutrition》2007,2(1):67-70
Quantitative epidemiological analysis suggests that about one third of the variation in cancer risk can be attributed to variation in dietary exposure but it has proved difficult, using conventional epidemiological approaches, to identify which dietary components, in what amounts and over what time-scales are protective or potentially hazardous. Work in this area has been hampered by the lack of robust surrogate endpoints. However, the rapidly accumulating knowledge of the biological basis of cancer and the application of post-genomic technologies are helping the development of novel biomarkers of cancer risk. Genomic damage resulting in aberrant gene expression is the fundamental cause of all cancers. Such damage includes mutations, aberrant epigenetic marking, chromosomal damage and telomere shortening. Since both external agents and normal cell functions, such as mitosis, subject the genome to frequent and diverse insults, the human cell has evolved a battery of defence mechanisms which (a) attempt to minimize such damage (including inhibition of oxidative reactions by free radical scavenging and the detoxification of potential mutagens), (b) repair the damage or (c) remove severely damaged cells by shunting them into apoptosis. When such defences fail and a tumour becomes established, further genomic damage and further alterations in gene expression enable the tumour to grow, to cope with anoxia, to develop a novel blood supply (angiogenesis), to escape from the confines of its initiation site and to establish colonies elsewhere in the body (metastasis). All of these processes are potentially modifiable by food components and by nutritional status. In addition, interactions between dietary (and other environmental and lifestyle) factors and genetic make-up [seen principally in the assembly of single nucleotide polymorphisms (SNPs) which is unique to each individual] contributes to interindividual differences in cancer risk. 相似文献
12.
Alana Cattapan 《New genetics and society》2017,36(1):43-65
This article examines how medical and scientific professionals experience and engage with the governance of embryo research in Canada. Drawing on the history of embryo regulation in Canada and the findings of a survey conducted with lab directors in Canadian fertility clinics, we identify a disjuncture between the rules established by legislation, regulations, and research ethics guidelines and the real-life experiences of professionals in the field. This disjuncture, we argue, is the result of both the absence of implementation mechanisms that would give substance to the governing framework, as well as an inability on the part of medical and scientific professionals to engage in robust self-regulation. Overall, we demonstrate that in an ethically charged and highly technical area of policy-making like embryonic research, clarity about the roles and responsibilities of government and professionals in policy-making and implementation is critical to effective governance. 相似文献
13.
Trevor A. Epp Ruoxiang Wang Michael J. Sole Choong-Chin Liew 《Journal of molecular evolution》1995,41(3):284-292
We have recently determined the complete nucleotide sequences of the cardiac - and -myosin heavy chain (MyHC) genes from both human and Syrian hamster. These genomic sequence data were used to study the molecular evolution of the cardiac MyHC genes.Between the - and -MyHC genes, multiple gene conversion events were detected by (1) maximum parsimony tree analyses, (2) synonymous substitution analyses, and (3) detection of pairwise identity of intron sequences. Approximately half of the 40 cardiac MyHC exons have undergone concerted evolution through the process of gene conversion with the other half undergoing divergent evolution. Gene conversion occurred more often in exons encoding the a-helical myosin rod domain than in the globular head domain, and an apparent directional bias was also observed, with transfer of genetic material occurring more often from to . 相似文献
14.
D. Ross Robertson Nicholas V. C. Polunin Kimberley Leighton 《Environmental Biology of Fishes》1979,4(2):125-170
Synopsis The relationship between the morphology, feeding strategies and social and mating systems of three surgeonfishes was investigated. Adults of each defend feeding territories, intra-and interspecifically. The largest species, because of its morphological limitation, relies on food that has to be defended against many other species. It forms large colonies in which fishes singly defend small territories containing high standing crop algal mats. Colony formation is a mechanism by which the efficiency and effectiveness of interspecific territory defense is increased. The smallest species, because of its morphological adaptations, is able to rely most on food that other species cannot efficiently exploit. It forms pairs that defend large territories containing a thin algal mat. It is restricted to the poorest quality habitat by the aggressive activities of more dominant species. The third species, which also forms pairs, has an intermediate feeding strategy. The local coexistence of these three and other surgeonfishes results from a combination of (i) their partitioning both habitat and food resources, and (ii) the populations of two of the most dominant species apparently being below the carrying capacity. Territoriality and the absence of parental care facilitates pair formation in surgeonfishes. Permanently territorial species usually form pairs. The colonial species does not form pairs because the colonial habit facilitates interference of males in each other's spawnings. 相似文献
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The evolution of parental care in fishes,with reference to Darwin's rule of male sexual selection 总被引:8,自引:0,他引:8
Jeffrey R. Baylis 《Environmental Biology of Fishes》1981,6(2):223-251
Synopsis A simple two part hypothesis is proposed to describe the sources of selection influencing the evolution of parental care in fishes. It is derived in part from the observation that most fishes exhibiting complex patterns of parental behavior are freshwater forms. The first aspect of the hypothesis assumes that differential zygote mortality occurs in spatially and temporally varying environments. The second assumes that rates of gametogenesis are faster in males than in females. These aspects interact to generate a series of predictions: 1. When the zygote requires an external resource such as an optimal site for development, and that resource is scarce relative to the breeding population and is reusable, the male should monopolize it (male reproductive territoriality). 2. When bearing is derived from male guarding, the male will be the bearer. 3. When bearing evolves from a condition other than male guarding, the female will be favored as the bearer and the male will be favored as the gamete donor. 4. In all of the above cases except male bearing, the males reproductive success is limited primarily by the number of females he can attract rather than his own rate of gamete production and hence the male will tend to be the sexually selected sex. These and other predictions are tested against the existing literature on reproduction in fishes, and competing hypotheses are critically reviewed. 相似文献
17.
Derek A. Roff 《Environmental Biology of Fishes》1988,22(2):133-146
Synopsis Migration is a common phenomenon in marine fishes but the consequences with respect to life history variation have been little
explored. Migration both influences the evolution of other traits and is contigent upon the evolution of other behavioural
and demographic characters. The interaction between such factors is illustrated by considering the relationship between the
cost of migration in relation to fecundity and the advantages and disadvantages of schooling, a phenomenon hypothesized to
favour the evolution of migration. These analyses predict that migratory species will be relatively large, mature late and
at a relatively large size and grow relatively fast. Data from north temperate marine fish support these predictions. 相似文献
18.
Scaling of growth and life history traits relative to body size, brain size, and metabolic rate in lorises and galagos (Lorisidae, primates) 总被引:1,自引:0,他引:1
A broad range of variation in body size, brain size, and metabolic rate occurs within the primate family Lorisidae, thus providing an opportunity to examine the relationship of these three parameters to variation in growth and life history traits. Data on adult body weight, gestation length, lactation length, age at first estrus, litter size, and growth parameters were collected from a captive colony of four lorisid species, Loris tardigradus, Nycticebus coucang, Galago crassicaudatus, and G. senegalensis. The data presented here constitute the most complete life history information available for these poorly understood prosimian species. Correlation and allometric analyses were performed to determine the relationships between variables. Among the lorisids studied, adult body weight, adult cranial capacity, and relative cranial capacity did not predict variation in life history traits. Adult basal metabolic rate predicted most of the variability in gestation length, lactation length, and growth parameters. Lorisines differ from similarly sized galagines in having lower basal metabolic rates, slower growth rates, slower developmental rates, and smaller litter sizes, resulting in reduced reproductive potential. This may be a consequence of lorisine adaptation to a diet of toxic insects. Metabolic rate and diet may be among the most important parameters to examine in any study of life history evolution. 相似文献
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目的克隆人RHD基因,并对其进行鉴定。方法以RhD阳性志愿者骨髓为材料,用TRIzol试剂提取总RNA;设计、合成人RHD基因扩增引物,RT-PCR方法扩增RHD基因片段;T/A克隆后将其亚克隆人pET28a(+)载体中,经酶切、PCR和测序对重组质粒进行鉴定。结果骨髓总RNA被成功提取;RT-PCR成功扩增出RHD基因片段,其大小与预期约509bp基本一致;T/A克隆后再将其亚克隆,通过酶切和PCR证明RHD基因成功亚克隆入pET28a(+)载体中;基因测序结果比对显示,与已公布的RHD基因(GenBank登录号为NM016124)序列基本一致,同源性为98%。结论成功克隆了RHD基因,这将为进一步研究奠定基础。 相似文献