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1.
本文报道了在云南新发现的 4种古蚖:热海古蚖Eosentomonrehaiense、腾冲古蚖E tengchongense、大孔古蚖E megastigma和古永古蚖E guyongense。它们的腹板Ⅳ~Ⅶ节毛序都是 6 /9型的。  相似文献   

2.
余山拟异蚖和3种古蚖的精子均为扁圆形,未见顶体,线粒体集中在一侧;核呈环形、边位、中部由膜状体分布其间.领结古蚖的早期精细胞为球形,染色质凝集成团,继而核中裂并沿细胞赤道逐渐围绕成环,染色质呈细沙状,胞间有“桥”相通.核膜一端开始内陷,出现黑点.待发育到中期精细胞,这些黑点逐渐形成奇特的管状核膜陷体;染色质变成短线形,随后排成4—5行.线粒体颗粒状,细胞间仍有“桥”连通.晚期精细胞的染色质凝集成粗带,最后形成光滑质密的核,而多余的核物质,一段一段从精子一端脱离,形成一串孢囊状体夹在精子之间,待精子成熟游离时,这些孢状体分散开来.从观察结果表明拟异蚖精子与古蚖的非常相近.  相似文献   

3.
记述了采自陕西省翠华山的新异蚖属1新种,即陕新异蚖Neanisentomonshaanicum sp.nov.。新种主要特征为:前足跗节感器b′-1和c′缺失,感器d极长大;腹部第Ⅴ~Ⅵ节背板缺少前排刚毛A3,毛序为8/16,第Ⅶ节背板缺少前排刚毛A1和A3,毛序为6/16;雌性外生殖器具有明显的鸭头状的头片。该新种可以通过前足跗节感器d的长度和雌性外生殖器等特征与已知种类区分。文中同时列出了新异蚖属的世界种类检索表。  相似文献   

4.
1984年岁末至次年初,刘祖尧和金根桃二位同志,自海南岛的五指山、尖峰岭和吊罗山等地,采集到原尾虫标本400多只,经鉴定共计有24种,其中肯蚖属的种类较为丰富,共有8种。除日本肯蚖〔Kenyentulus japonicus(Imadate 1961)〕河南肯蚖(K.henanensis Yin 1983),景洪肯蚖(K.jinghongensis Yin 1983)和小肯蚖(K.  相似文献   

5.
记述了采自青海省的夕蚖属2新种,即西宁夕蚖Hesperentomon ciningense sp.nov.和南山夕蚖Hesperentomon nanshanensis sp.nov.,两新种腹部第Ⅱ~Ⅵ节背板后排具有6对刚毛,毛序为8/12,第Ⅳ~Ⅵ节腹板缺失后排中刚毛Pc,毛序为4/8.西宁夕蚖和南山夕蚖相似,二者可以通过颚腺、雌性外生殖器、前足跗节的长度、感器形状以及腹部第Ⅹ节的毛序加以区分.新种模式标本保存在上海昆虫博物馆.  相似文献   

6.
1973年冬采自云南西双版纳地区的一批原尾虫标本,经近年来陆续鉴定发表的23种外,尚有檗蚖科的5个种,其中包括4个新种和1个新记录,现记述于后。 模式标本均保存于中国科学院上海昆虫研究所。 扇饰格蚖 Gracilentulus flabelli,新种(图1—10) 全长1032微米。头长112微米,宽88微米,下唇须具3刚毛和1根长形感器。假眼  相似文献   

7.
中国东北原尾虫一新种记述(原尾纲,蚖科)   总被引:1,自引:0,他引:1  
记述了采自辽宁省鞍山市千山的原尾虫1新种,千山线毛蚖Filientomon qianshanense sp. nov.,新种第Ⅱ、Ⅲ对腹足上各仅具1根刚毛,前足跗节末端的爪上具有内外悬片各1个.文中给出了线毛蚖属世界种类检索表.新种模式标本保存在上海昆虫博物馆.  相似文献   

8.
谢荣栋 《动物学研究》2000,21(3):210-217
描述了采自云南的6个古Yuan新种:高黎贡古YuanEosentomon gaoligongense、怒江古YuanE.nujiangense、紫溪古YuanE.zixiensis、初劝古YuanE.luquanense、盈江古YuanE.yingjiangens和瑞丽古YuanE.rniliense。  相似文献   

9.
报道了采自我国东北地区吉林省长春市原尾虫1新种,长春巴蚖 Baculentulus changchunensis sp.nov..新种与采自朝鲜的 B.weinerae Szeptycki and Imadaté,1987以及采自日本的B.densus Imadaté,1960毛序相似,均为腹部Ⅰ~Ⅵ节背板Pla毛缺失.其与前者差别主要在于前跗感觉毛d位置、f和g长度、颚腺形状、栉梳形状和齿数,与后者差别主要体现在前跗感觉毛t-3大小、f和g末端位置、下唇须感觉毛形状和雌性生殖器.新种模式标本保存在中国科学院上海植物生理生态所昆虫博物馆.  相似文献   

10.
云南古Yuan属四新种(原尾纲:古Yuan目)   总被引:1,自引:1,他引:0  
本文报道了在云南新发现的4种古YuanEosentomon rehaiense、腾冲古YuanE.tengchongense、大孔古YuanE.megastigma和古永古YuanE.guyongense。它们的腹板Ⅳ-Ⅶ节毛序都是6/9型的。  相似文献   

11.
Apolipoprotein E (apoE) genotypes were determined in 165 Saudis. The prevalence of genotype, E3/E3, E3/E4 and E4/E4 was found to be 71, 27 and 2% respectively. The E3/E3 was the most prevalent genotype among the Saudis followed by E3/E4. However, other genotypes E2/E2, E2/E3 and E2/E4 were absent showing the absence of E2 allele in the test population. The high frequencies of the E3 allele (0.845) and E3/E3 genotype (0.71) and absence of E2 allele in Saudis under study are similar to those reported earlier for Native Americans, Mexican-Americans, Mayans, Cayapa, Mazatecan Indians and Mexican Mestizos populations.  相似文献   

12.
This paper consists of a part of pertinent data obtained through a critical study of Eriocaulaceae from China. Included in it are three new series: Leiantha, Robustiora and Mangshanensia; seven new species: Eriocaulon acutibracteatum, E. angustulum, E. bilobatum, E. leianthum, E. sclerophyllum, E. glabri-petalum and E. mangshanense; five new varieties: E. rockianum var. latifolium, E. merrillii var. longibracteatum, E. sikokianum var. Linanense, E. alpestre var. sichanense and E. nantoense var. micropetalum; two new combinations: E. yaoshanense var. brevicalyx; E. nantoense var. parviceps; three new records in China: E. brownianum, E.brownianum var.nilagirense, E. zollingerianum; five: E. henryanum, E.pullum, E. yaoshanense, E. taishanense and E.faberi. In addition, fifteen taxon names are newly reduced to synonyms: E. yunnanense=E. brownianum; E. longifolium, E. sexangulare var. longifolium, E. sinii, E. kwangtungense and E. willdinovianum = E. sexangulare; E. setaceum var. capillus-naiadis= E. setaceum; E. filifolium = E. yaoshanense; E. suishaense, E. merrillii var. suishaense=E.merrillii; E. kengii=E.sikokianum; E. whangii=E.buergerianum; E. nipponicum, E. decemflorum var. nipponicum= E. decemflorum and E. nantoense var.trisectum = E. nantoense var.parviceps.  相似文献   

13.
DNA-damage response control of E2F7 and E2F8   总被引:2,自引:0,他引:2  
Here, we report that the two recently identified E2F subunits, E2F7 and E2F8, are induced in cells treated with DNA-damaging agents where they have an important role in dictating the outcome of the DNA-damage response. The DNA-damage-dependent induction coincides with the binding of E2F7 and E2F8 to the promoters of certain E2F-responsive genes, most notably that of the E2F1 gene, in which E2F7 and E2F8 coexist in a DNA-binding complex. As a consequence, E2F7 and E2F8 repress E2F target genes, such as E2F1, and reducing the level of each subunit results in an increase in E2F1 expression and activity. Importantly, depletion of either E2F7 or E2F8 prevents the cell-cycle effects that occur in response to DNA damage. Thus, E2F7 and E2F8 act upstream of E2F1, and influence the ability of cells to undergo a DNA-damage response. E2F7 and E2F8, therefore, underpin the DNA-damage response.  相似文献   

14.
Apolipoprotein E (apoE) genotypes were determined in 165 Saudis. The prevalence of genotype, E3/E3, E3/E4 and E4/E4 was found to be 71, 27 and 2% respectively. The E3/E3 was the most prevalent genotype among the Saudis followed by E3/E4. However, other genotypes E2/E2, E2/E3 and E2/E4 were absent showing the absence of E2 allele in the test population. The high frequencies of the E3 allele (0.845) and E3/E3 genotype (0.71) and absence of E2 allele in Saudis under study are similar to those reported earlier for Native Americans, Mexican-Americans, Mayans, Cayapa, Mazatecan Indians and Mexican Mestizos populations.  相似文献   

15.
The purposes of this experiment were: (1), to compare effect of three E64 derivatives, E64, E64c and E64d in preventing nuclear opacity and proteolysis in calcium ionophore-induced cataract and (2), to measure the accumulation of E64 derivatives in the cultured lenses. In vitro E64 and E64c strongly inhibited purified calpain II from porcine heart, while E64d showed weaker inhibition than E64 and E64c. In cultured lenses, all three E64 derivatives reduced nuclear opacity by calcium ionophore A23187 in a concentration-dependent manner, and E64D, the ethyl-ester of E64c, was the most effective. When lenses were cultured in E64d for 2 h, the resulting concentration of E64 derivative in the lens was markedly higher than during culture in E64 of E64c. All three E64 derivatives prevented proteolysis of crystallins seen in A23187 cataract. The stronger effect of E64d against A23187 cataract was likely due to an earlier penetration into the lens, conversion to E64c and inhibition of activated calpain.  相似文献   

16.
Human papillomavirus 16 (HPV16) E6E7 pre-mRNA is bicistronic and has an intron in the E6 coding region with one 5' splice site and two alternative 3' splice sites, which produce E6(*)I and E6(*)II, respectively. If this intron remains unspliced, the resulting E6E7 mRNA expresses oncogenic E6. We found for the first time that the E6E7 pre-mRNA was efficiently spliced in vitro only when capped and that cellular cap-binding factors were involved in the splicing. The cap-dependent splicing of the E6E7 pre-mRNA was extremely efficient in cervical cancer-derived cells, producing mostly E6(*)I, but inefficient in cells transfected with a common retrovirus expression vector, pLXSN16E6E7, due to the large size of this vector's exon 1. Further studies showed that efficient splicing of the E6E7 pre-mRNA depends on the distance of the cap-proximal intron from the RNA 5' cap, with an optimal distance of less than 307nt in order to facilitate better association of U1 small nuclear RNA with the intron 5' splice site. The same was true for splicing of human beta-globin RNA. Splicing of the E6E7 RNA provided more E7 RNA templates and promoted E7 translation, whereas a lack of RNA splicing produced a low level of E7 translation. Together, our data indicate that the distance between the RNA 5' cap and cap-proximal intron is rate limiting for RNA splicing. HPV16 E6E7 pre-mRNA takes advantage of its small cap-proximal exon to confer efficient splicing for better E7 expression.  相似文献   

17.
18.
The pyruvate dehydrogenase complex of Escherichia coli was isolated in a simple three-step procedure. Its chain stoichiometry, determined by trinitrobenzoate modification was found to be 1.4 E1:1 E2:0.6 E3. It was reproducible within 10% from preparation to preparation. The E. coli complex was resolved by chromatography on activated thiol Sepharose. Reconstitution of activity yielded a stoichiometry of 1.0 E1:1 E2:0.5 E3. The optimum binding stoichiometry of E1E2 and E2E3 subcomplexes was determined by sedimentation experiments and found to be 2.0 E1:1 E2 and 2.5 E3:1 E2, respectively. Competition between E1 and E3 was observed in the binding experiments, but not in the kinetic experiments. Hybrid active complexes could be reconstituted from either an E1E2 subcomplex from Azotobacter vinelandii and the E3 component from E. coli or from E2E3 subcomplex from E. coli and the E1 component from A. vinelandii. Low activity and weak binding was observed when E1 from E. coli was recombined with an E2E3 subcomplex from A. vinelandii or when E3 from A. vinelandii was recombined with an E1E2 subcomplex from E. coli. The association behaviour and stoichiometry of the reconstituted complexes is determined by the nature of the E2 component. The formation of hybrid complexes indicates a considerable structural similarity between the complexes from both sources, despite the differences in size and stoichiometry.  相似文献   

19.
本文利用作者建立的密度梯度超速离心分离VLDL的新方法和分析等电聚焦电泳,测定了95例中国人Apo-E基因多态性和其表型分布以及血脂水平。所得表型分布趋势与国外报告一致:E_3/E_3频率最高,E_3/E_2和E_3/E_4次之,E_4/E_4,E_4/E_2和E_2/E_2最低。同对发现中国人群的E_3/E_3表型百分分布明显高于西方人群,但未发现有E_2/E_2表型。我国人群Apo-E表型分布的这种特征可能与中国人群冠心病的患病率较西方人群为低有关。血清脂质测定和分析表明,具有不同表型人群的血脂水平无显著的统计学差异。  相似文献   

20.
E1 and E2 glycoproteins are structural components of hepatitis C virus (HCV) virion. They are involved in cellular receptors interaction, neutralising antibodies elicitation, and viral morphogenesis. They are considered as major candidates for anti-HCV vaccine. In this report, we first expressed tandem E1E2 as well as C-terminally truncated E1 fragment and C-terminally truncated E2 fragment, respectively, in Escherichia coli cells and the proteins were purified to homogenesis. All the purified proteins can react specifically with patient sera. Both purified chimeric protein E1E2 and protein E2 can interact with a putative cellular receptor CD81, while purified protein E1 cannot interact with CD81. The sera of rabbit immunized with the E1E2 inhibited the binding of E2 protein to the major extracellular loop of human CD81 and reacted with both proteins E1 and E2, respectively. Anti-E1 and E2 antibodies can be generated simultaneously in the rabbit immunized with the E1E2, and the titers of antibodies were 63 or 56% higher than the titers induced by E1 or E2 alone, respectively. The results suggest that E1 and E2 can enhance their immunogenicity each other in chimeric protein E1E2 and the E. coli-derived chimeric protein E1E2 and corresponding antisera can be used as an useful tools in anti-HCV vaccine research.  相似文献   

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