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1.
<正>There is no experiencing without an experiencer,the self.Whether the experiencer knows it is"the self"that is experiencing is a different and tricky philosophical issue.Dating back to Ivan Pavlov’s dogs,the"experience"of animals has  相似文献   
2.
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   
3.
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   
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5.
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   
6.
家蚕转基因载体pBacA3EG的构建及其表达   总被引:2,自引:0,他引:2  
以家蚕Bombyx mori肌动蛋白A3(actin 3)启动子、增强性绿色荧光蛋白(enhanced green fluorescent protein, EGFP)基因及SV40的多聚腺苷酸识别序列为元件,经多次克隆,将其插入到piggyBac转座载体中。经PCR、酶切鉴定及测序表明各元件已按正确的方式插入到piggyBac载体中。将构建好的piggyBac表达载体显微注射到胚盘形成前期的蚕卵中,在胚胎早期发育的第3天,通过体视荧光显微镜检测到蚕卵内发出较强的绿色荧光。结果表明该载体构建正确且能在蚕卵中进行表达。家蚕转基因载体的体外瞬时表达不但是成功进行家蚕转基因所必需的第一步,而且其自身也可以应用于基因的功能研究,为家蚕后基因组研究奠定了基础。  相似文献   
7.
Sinoinsula nom. nov. = Insuht Zhou & Li, 2013. Zootaxa 3712 (I): 11.  相似文献   
8.
Detection and Genetic Characterization of Rabies Virus from Human Patients   总被引:1,自引:0,他引:1  
Saliva and blood were collected from two patients who had not received post exposure prophylaxis in the cities of Wenzhou and Xinning respectively. Both patients were confirmed as positive for rabies by detection of rabies virus specific nucleoprotein antibodies in the sera by Western Blot. However, rabies virus specific RNA was only identified in the saliva collected from the patient in Wenzhou. Furthermore, the isolate Zhejiang Wz0 (H) was obtained by inoculating one-day-old suckling mice. Both nucleoprotein (N) and glycoprotein (G) genes from the isolate were amplified by RT-PCR and sequenced. Phylogenetic analysis indicated that the isolate belonged to classic rabies virus, and shared a higher homology with the street viruses from dogs in the main endemic areas in China and the street virus from dogs in Indonesia than with other known strains. Further comparison of the deduced amino acid sequences between the isolate and the vaccine strains used in China showed that the virus had a higher level of homology with the vaccine strain CTN than with the other vaccine strains (3aG, PV, PM and ERA). In particular, amino acid residues substitutions located in antigenic site Ⅲ in the G protein, which could react with the neutralizing antibodies, were observed. These results suggested that the virus belonged to the classic rabies virus, and both N and G genes diverged from the current vaccine strains used in China at either the nucleotide or the amino acid level.  相似文献   
9.
Copyright by Science in China Press 2005 Primary hepatocarcinoma is one of the most fre-quent digestive-tract cancers, particularly in China. The incidence and death rate of primary hepatocarci-noma in China is the highest in the world, with about 1100 thousands people dying from primary hepatocar-cinoma per year[1]. Although the chemotherapeutic agents are the main therapeutic approach for hepato- carcinoma, they are relatively ineffective and result in many toxic and side effects. Accordin…  相似文献   
10.
Jk (kidd) blood group antigens are carried by the urea transporter UT-B[1,2]. The Jknull phenotype, lack-ing urea permeability in erythrocytes[3,4], has a very low frequency in all populations except Polynesians and Finns[5]. In Japan, only 14 individuals with Jk (a-b-) phenotype were identified from 638460 screened donor’s blood samples using the 2 mol/L urea solution hemolysis test[6]. The frequency of Jknull is 0.27% in Polynesian, about 0.03% in Finland[7], and extremely rare in Fran…  相似文献   
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