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91.
Tylonycteris pachypus is a gregarious bat species with tens of individuals in a colony. The mechanisms by which mother bats recognize their pups and adult bats recognize each other are not clear. We hypothesized that such recognition is achieved by chemical discrimination and performed experiments to test the hypothesis. Results showed that mother bats were much more attracted to the scent from their own pups. For adult bats, females were attracted to the scent from both male and female groupmates but had a higher preference to the scent from female than from male groupmates. Male bats were much more attracted to the scent from male groupmates while showed no preference to the scent from female groupmates. Within a group, both female and male bats had no difference in preference to the scent from the same or opposite sex. These results suggest that mother–pup and groupmate recognition of T. pachypus can be achieved by olfactory cues. 相似文献
92.
PCR及其衍生技术在基因突变检测中的应用 总被引:3,自引:1,他引:3
许多人类遗传性疾病及某些抗艾滋病药物的抗性乃至细菌对某些抗生素的抗药性通常源于基因突变。本文对近年来在基因突变检测中应用日益广泛的各种PCR 衍生技术作一综述;重点介绍了错配PCR技术,以及我们实验室近期报道的一种快速检测喹诺酮类药物耐药大肠杆菌的错配PCR方案。
Abstract:Many inherited diseases and drug resistance have been attributed to mutations in corresponding genes.In this paper,several techniques based on PCR used in diagnosis were concluded.The development and research progress of Mismatch PCR were discussed in details.Some information about an assay that we developed for detection of antimicrobial resistance to quinolones was also described. 相似文献
93.
自然干燥对冬虫夏草寄主蝠蛾卵孵化的影响 总被引:1,自引:0,他引:1
研究在室内自然空气湿度下放置的时间长短对冬虫夏草(Cordyceps)寄主昆虫贡嘎蝠蛾Hepialus gonggaensis Fu et Huang卵孵化率的影响。卵早期的研究结果为:第1批、第2批和第3批卵于室内自然空气湿度下保存的时间达26,11和16h后再保湿都可以正常孵化并且孵化率与对照无显著性差异,所孵化幼虫在饲养初期的成活率分别达62.0%,41.4%和43.4%,与对照无显著性差异。卵中期干燥放置36h的孵化率为66.7%,所孵化幼虫在饲养初期的成活率为50.0%,孵化率和成活率都与对照无显著性差异。卵晚期干燥放置24h的孵化率为70.0%,所孵化幼虫在饲养初期的成活率为49.0%,孵化率和成活率都与对照无显著性差异。以上结果表明,经历一定时间的干燥不会对卵的正常孵化有影响。 相似文献
94.
目的:优化现有的甲胎蛋白异质体(AFP-L3)分离和检测方法,找到一个最有效的AFP-L3的提取方法,为今后的AFP-L3研究奠定前期基础。方法:应用北京热景生物技术公司的甲胎蛋白异质体(AFP-L3)亲和吸附离心管,通过改变亲和介质使用量和洗脱液体积的配伍梯度变化来优化实验流程,排除提取AFP-L3的影响因素,分离血清中的AFP-L3,并用罗氏公司的甲胎蛋白检测试剂盒检测分离的效果。结果:发现在不改变亲和介质体积的情况下,随着洗脱液体积的减少AFP-L3回收浓度逐渐增加,且在75 ul洗脱液时能够获得最高AFP-L3回收浓度。结论:成功地优化了北京热景生物技术公司的甲胎蛋白异质体(AFP-L3)亲和吸附离心管及其配套试剂的使用方法。 相似文献
95.
记述中国分布的长头网蝽属昆虫5种,其中包括1新种,鄂长头网蝽Cantacader hubeianus sp.nov., 2个中国新纪录种,日本长头网蝽 C. japanicus Drake, 1947和五脊长头网蝽 C. quinquecostatus (Fieber, 1844)。给出了长头网蝽属中国种类检索表和23幅形态图。模式标本保存于南开大学昆虫标本室。 相似文献
96.
大豆属Soja亚属种皮微形态特征的研究 总被引:1,自引:0,他引:1
采用扫描电镜对大豆属Soja亚属植物的种皮微形态特征进行了系统研究。结果表明,该亚属植物种皮微形态特征在种的水平上具有一定的分类学意义。 相似文献
97.
Sun W Xing B Sun Y Du X Lu M Hao C Lu Z Mi W Wu S Wei H Gao X Zhu Y Jiang Y Qian X He F 《Molecular & cellular proteomics : MCP》2007,6(10):1798-1808
Hepatocellular carcinoma (HCC) is a highly malignant tumor, and chronic infection with hepatitis B virus is one of its major risk factors. To identify the proteins involved in HCC carcinogenesis, we used two-dimensional fluorescence DIGE to study the differentially expressed proteins in tumor and adjacent nontumor tissue samples. Samples from 12 hepatitis B virus-associated HCC patients were analyzed. A total of 61 spots were significantly up-regulated (ratio >/= 2, p = 0.01) in tumor samples, whereas 158 spots were down-regulated (ratio = -2, p = 0.01). Seventy-one gene products were identified among these spots. Members of the heat shock protein 70 and 90 families were simultaneously up-regulated, whereas metabolism-associated proteins were decreased in HCC samples. The down-regulation of mitochondrial and peroxisomal proteins in these results suggested loss of special organelle functions during HCC carcinogenesis. Four metabolic enzymes involved in the methylation cycle in the liver were down-regulated in HCC tissues, indicating S-adenosylmethionine deficiency in HCC. Two gene products, glyceraldehyde-3-phosphate dehydrogenase and formimidoyltransferase-cyclodeaminase, were identified from inversely altered spots, suggesting that different isoforms or post-translational modifications of these two proteins might play different roles in HCC. For the first time, the overexpression of Hcp70/Hsp90-organizing protein and heterogeneous nuclear ribonucleoproteins C1/C2 in HCC tissues was confirmed by Western blot and then by immunohistochemistry staining in 70 HCC samples, suggesting their potential as protein tumor markers. In summary, we profiled proteome alterations in HCC tissues, and these results may provide useful insights for understanding the mechanism involved in the process of HCC carcinogenesis. 相似文献
98.
1-羟基-2-甲基-2-E-丁烯基-4-焦磷酸还原酶(HDR)是甲基-D-赤藓醇-4-磷酸(MEP)途径中的最后一个酶,在植物萜类生物合成中起主控作用。该研究根据思茅松(Pinus kesiya var.langbianensis)树皮转录组数据分析结果,首先获得了思茅松HDR基因片段,然后根据所获得的基因片段设计特异引物,提取受伤后的思茅松树皮的RNA,并运用RT-PCR和RACE技术从思茅松树皮中克隆得到完整的HDR基因(Pk HDR)。生物信息学分析表明:克隆获得的Pk HDR1基因c DNA全长序列为1 876 bp,含有1个1 464 bp的开放阅读框(ORF),编码487个氨基酸。同源性分析结果表明:思茅松HDR蛋白与赤松(Pinus densiflora)HDR蛋白的相似性高达99%。亚细胞定位及结构域分析结果表明:思茅松Pk HDR氨基酸序列中包含转运肽序列(A1-A61)及植物HDR蛋白多个保守的功能位点(A143,A234,A288,A371)。系统进化分析结果表明:Pk HDR蛋白与赤松HDR蛋白的亲缘关系最为接近。半定量PCR检测结果表明:树皮的创伤促进思茅松HDR基因的表达。该研究成功克隆获得HDR基因,并确定其与松脂代谢密切相关,为阐明思茅松松脂生物合成机制和分子育种提供了参考。 相似文献
99.
Concurrent observations of soil water potential and leaf stomata diffusion resistance were made on two, plots of wheat grown at Datun Agro-ecological Experimental Station in Beijing under two different soil water conditions. These data were further complemented by weather and physiological observation. In this paper, we mainly analysed the influence of soil water potential on the status of wheat leaf stomatal resistance. The results indicate that: (1) there is a obvious influence of soil water potential on the status of wheat leaf stomata under normal conditions and (2) there is a different upper and lower epidermis stomata of wheat leaf respond to the soil water potential. The lower epidermis stomata are more sensitive to soil water potential than upper epidermis one. (3) There is a linear relationship between the ratio of lower and upper epidermis stomata resistance and soil water potential in root layer, according to this we can diagnose the degree of wheat water deficit. 相似文献
100.