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排序方式: 共有169条查询结果,搜索用时 15 毫秒
1.
Yi-Lin ZHOU Xia QIU Xiao-Bin FANG Lu-Yi YANG Yi ZHAO Teng FANG Wei-Hong ZHENG Jin-Song LIU 《动物学研究》2014,35(1):42-50
Anurans often have species-specific vocalizations. To quantify and compare the characteristics of anuran calls in Gutianshan National Nature Reserve, Zhejiang Province, we recorded the advertisement calls of eight species belonging to four families (Ranidae, Microhylidae, Megophryidae and Bufonidae) from June to September 2012 using Sony ICD-FX8 IC recorders. All recordings were analyzed using the "Praat" software. Five acoustics parameters were measured, including temporal traits (call duration, number of notes or pulse number/call) and spectral traits (fundamental frequency, the first three formants and dominant frequency). The characteristic parameters of Microhyla ornate and Fejervarya limnocharis calls were different as were the calls of some populations of the same species recorded in different regions. The advertisement calls of the eight species were specific. Our study has provided a useful reference for identifying the calls of some common Chinese anurans. 相似文献
2.
李永全 郑克勤 周汝滨 潘超仁 廖霞 陈小萍LI Yong-quan ZHENG Ke-qin ZHOU Ru-bin PAN Chao-ren LIAO Xia CHEN Xiao-ping 《遗传》1999,21(6):10-185
在2 703例遗传咨询门诊病例中检出9号染色体臂间倒位21例,将本组inv(9)的频率与普通群体inv(9)的频率作比较,并通过对伴有其它性状的inv(9)家系的分析,讨论了inv(9)的遗传效应问题。
Abstract: Twenty one cases of pericentric inversion of chromosome 9 were found in 2703 patients asking genetic counseling. The percentage of inv(9) in this group was compared with that in normal population. Two special pedigrees with inv(9) were analyzed and the genetic effects of inv(9) were discussed. 相似文献
3.
SRY盒基因在斑马鱼和胡子鲇中的保守性分析 总被引:7,自引:2,他引:7
本文采用人类SRY基因探针,与EcoRI消化的中国的胡子鲇(Clarias fusc us)和美国的斑马鱼(Brachydanio rerio)基因组DNA进行了Southern印迹杂交分析。首次在这两种鱼中发现了SRY盒基因及其存在特征;在斑马鱼中发现了明显的限制性片段长度多态性; 并深入分析了SRY盒基因的进化保守性。
Abstract:Using,Southern bloting analysis,EcoRI-digested genomic DNA from Clarias fuscus and Brachydanio rerio were hybridizae to human SRY probe.Hybridization occurred in both male and female of the two species.RFLP associated with SRY-box genes was observed in Brachydanio rerio.The conservation of SRY-box genes was analysed. 相似文献
4.
QIU Yang WANG ZhaoWei LIU YongXiang QI Nan SI Jie XIANG Xue XIA XiaoLing HU YuanYang ZHOU Xi 《中国科学:生命科学英文版》2013,56(8):711-714
Insects are a group of arthropods and the largest group of animals on Earth,with over one million species described to date.Like other life forms,insects suffer from viruses that cause disease and death.Viruses that are pathogenic to beneficial insects cause dramatic economic losses on agriculture.In contrast,viruses that are pathogenic to insect pests can be exploited as attractive biological control agents.All of these factors have led to an explosion in the amount of research into insect viruses in recent years,generating impressive quantities of information on the molecular and cellular biology of these viruses.Due to the wide variety of insect viruses,a better understanding of these viruses will expand our overall knowledge of their virology.Here,we review studies of several newly discovered RNA insect viruses in China. 相似文献
5.
6.
WANG LiHan HU XinYang ZHU Wei JIANG Zhi ZHOU Yu CHEN PanPan WANG JianAn 《中国科学:生命科学英文版》2014,57(2):171-180
Autophagy is the basic catabolic progress involved in cell degradation of unnecessary or dysfunctional cellular components.It has been proven that autophagy could be utilized for cell survival under stresses.Hypoxic-preconditioning(HPC)could reduce apoptosis induced by ischemia and hypoxia/serum deprivation(H/SD)in bone marrow-derived mesenchymal stem cells(BMSCs).Previous studies have shown that both leptin signaling and autophagy activation were involved in the protection against apoptosis induced by various stress,including ischemia-reperfusion.However,it has never been fully understood how leptin was involved in the protective effects conferred by autophagy.In the present study,we demonstrated that HPC can induce autophagy in BMSCs by increased LC3-II/LC3-I ratio and autophagosome formation.Interestingly,similar effects were also observed when BMSCs were pretreated with rapamycin.The beneficial effects offered by HPC were absent when BMSCs were incubated with autophagy inhibitor,3-methyladenine(3-MA).In addition,down-regulated leptin expression by leptin-shRNA also attenuated HPC-induced autophagy in BMSCs,which in turn was associated with increased apoptosis after exposed to sustained H/SD.Furthermore,increased AMP-activated protein kinase phosphorylation and decreased mammalian target of rapamycin phosphorylation that were observed in HPC-treated BMSCs can also be attenuated by down-regulation of leptin expression.Our data suggests that leptin has impact on HPC-induced autophagy in BMSCs which confers protection against apoptosis under H/SD,possibly through modulating both AMPK and mTOR pathway. 相似文献
7.
豇豆轻斑驳病毒(Cowpea mild mottle virus,CPMMV)的流行与其媒介昆虫烟粉虱Bemisia tabaci密切相关,但CPMMV感染寄主植物对B型烟粉虱寄主选择行为和生物学特性的影响尚不清楚。本研究探究了1)CPMMV感染菜豆Phaseolus vulgaris不同时间对B型烟粉虱寄主选择和产卵偏好性的影响;2)CPMMV感染菜豆对B型烟粉虱生物学特性的影响。结果发现:1)相较于健康菜豆,摩擦接种CPMMV后1周,B型烟粉虱却偏好在CPMMV感染的植株上停留和产卵;而摩擦接种后4周,B型烟粉虱却偏好在健康的植株上停留和产卵;2)无论是在摩擦接种后1周和4周的CPMMV感染植株上,B型烟粉虱在健康和CPMMV感染植株上的产卵量和存活率差异不明显。可见,CPMMV感染菜豆对于B型烟粉虱的寄主选择偏好性具有时间效应,而CPMMV感染菜豆对于B型烟粉虱的生物学特性没有显著影响。 相似文献
8.
XIAO-DONG YU TIAN-HONG LUO JIAN YANG HONG-ZHANG ZHOU 《Insect Science》2006,13(2):127-135
Abstract The influence of edge effect on ground-dwelling beetles (Coleoptera) across a forest-clearcut ecotone was studied in Wolong Natural Reserve, southwestern China. During the field research, a total of 30 739 beetles were collected with pitfall traps along transects, which extending 100 m from the edge into the forest interior and 100 m into the clearcut. Of the collection, Carabidae comprised 92%, Staphylinidae 3%, Curculionidae 2%, and Tenebrionidae 2%, and these four families can be considered as abundant groups. Family richness, Shannon diversity and equitability display a significant decrease from forest interior, edge to clearcut. Based on the family composition and abundance, ground-dwelling beetles of the forest interior can be separated from those in the clearcut by Principal coordinate analysis ordination, and beetle assemblages in the forest edge were more similar to forest assemblages than to those found in the clearcut by cluster analysis. Seasonal dynamics of family richness showed a monotone peak in the middle season, with a highest value in the forest interior and a lowest value in the clearcut. Family abundance showed two peaks in the middle season, always with more individuals in the clearcut than in the forest interior or in the edge. Multiple linear regression analyses showed that the cover of shrub and litter were the two most important factors in determining family richness, Shannon diversity, equitability and abundance. Our results show that the forest edge and clearcut have obviously different composition and diversity of ground-dwelling beetles from forest interior at the family level. However, more edges have been formed due to increasing forest fragmentation (clearcutting or logging), so it is necessary to preserve large and intact forest to protect the diversity of ground-dwelling beetles in Wolong Natural Reserve. 相似文献
9.
马伯军 王文明 赵彬 周永力 朱立煌 翟文学MA Bo-Jun ) WANG Wen-Ming) ZHAO Bin) ZHOU Yong-Li) ZHU Li-Huang) ZHAI Wen-Xue) 《遗传》1999,21(3):9-714
根据与水稻抗白叶枯病基因Xa-4紧密连锁的分子标记M55的序列设计引物,通过对国际水稻研究所育成的抗白叶枯病近等基因系和基因累加系的叶片DNA、半粒种子提取物及Xa-4基因的杂合体DNA的PCR特异扩增,初步建立了Xa-4的PCR标记体系。进而用该标记体系对我国籼型杂交水稻常用的亲本材料进行分析,揭示出了Xa-4在这些材料中的分布情况。
Abstract Based on the sequence of a DNA marker tightly linked to the rice bacterial blight(BB) resistance gene Xa-4, two primers were designated and synthesized to develop a PCR marker for the gene. Specific amplified polymorphism analysis was carried out with these primers on a set of BB resistance isogenic lines and pyramided lines developed by IRRI. Two PCR bands were revealed corresponding to lines with dominant Xa-4 and those with the recessive allele, respectively, regardless the lines pyramided with other resistance genes. A hybrid with heterozygous Xa-4 produced both of the two allele PCR pattern. Then, the PCR marker was used to survey a range of hybrid rice germplasm. The results of the germplasm survey will be useful in hybrid rice breeding programs aimed at exploiting Xa-4. 相似文献
10.
ZHOU Jie'''' ZHAO Ruqian WEI Xihui XIA Dong XU Qingfu & CHEN Jie . Key Laboratory of Animal Physiology Biochemistry Ministry of Agriculture Nanjing Agricultural University Nanjing China . Anhui Agricultural University Hefei China 《中国科学:生命科学英文版》2004,47(2):190-196
~~Developmental patterns of serum leptin levels, leptin gene expression in adipose tissue and Ob-Rb gene expression in hypothalamus of Erhualian and Large White pigs~~ 相似文献