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41.
The phylogeny of howler monkeys (Alouatta, Platyrrhini): Reconstruction by multicolor cross-species chromosome painting 总被引:2,自引:0,他引:2
Edivaldo H. C. de Oliveira Michaela Neusser Wilsea B. Figueiredo Cleusa Nagamachi Julio Cesar Pieczarka Ives J. Sbalqueiro Johannes Wienberg Stefan Müller 《Chromosome research》2002,10(8):669-683
We performed multidirectional chromosome painting in a comparative cytogenetic study of the three howler monkey species Alouatta fusca, A. caraya and A. seniculus macconnelli (Atelinae, Platyrrhini) in order to reconstruct phylogenetic relationships within this genus. Comparative genome maps between these species were established by multicolor fluorescence in-situ hybridization (FISH) employing human, Saguinus oedipus and Lagothrix lagothricha chromosome-specific probes. The three species included in this study and previously analyzed howler monkey species were subjected to a phylogenetic analysis on the basis of a data matrix comprised of 98 discrete molecular cytogenetic characters. The results revealed that howler monkeys represent the genus with the most extensive karyotype diversity within Platyrrhini so far analyzed with high levels of intraspecific chromosomal variability. Two different multiple sex chromosome systems were identified. The phylogenetic analysis indicated that Alouatta is a monophyletic clade which can be derived from a proposed ancestral Atelinae karyotype of 2n=62 chromosomes by a chromosome fusion, a fission, a Y-autosomal translocation and a pericentric inversion. Following these suggestions, the genus Alouatta can be divided into two distinct species groups: the first includes A. caraya and A. belzebul, the second A. s. macconnelli, A. sara, A. s. arctoidea and A. fusca. 相似文献
42.
镉对大鼠肾脏和睾丸毒性的比较 总被引:2,自引:0,他引:2
大鼠饮水中给镉12wk后,检测了尿低分子蛋白(LMWP)排出量。尿碱性磷酸酶(ALP)活性,血清睾酮水平,睾丸乳酸脱氢酶同功酶(LDH-X)活性,精子计数和形态,雄鼠生育力,肾,睾丸和附睾组织镉含量,并在光镜和电镜下观察上述组织的病理变化,从生化,形态和功能改变三方面比较了大鼠肾脏和睾丸对镉的敏感性,发现尿LMWP和ALP仅在高剂量组显著增加,而血清睾酮和睾丸LDH-X在中剂量纽和低剂量纽已明显降低,说明镉对睾丸的有害作用可出现在肾脏之前。 相似文献
43.
44.
LARBI EL-MASDOURI ANDR AUBRY GUY BOUSSARD MICHEL MARRAUD 《Chemical biology & drug design》1992,40(6):482-486
The similar conformations and interaction modes of Ac-DL-Leu-Nme2 and Ac-Δ-Leu-NMe2 molecules in the solid state allow the comparison of their geometrical parameters. The most evident variations are essentially restricted to the α,β-unsaturated side-chain which adopts the Z-disposition. The dimensions of the peptide backbone are much less sensitive to α,β-unsaturation, with a small shortening by 0.04 Å and 0.02 Å of the N-Cα and Cα-C′ bonds, respectively, and an increase by 6° of the N-Cα- C′ bond angle. The ethylenic and amide groups in the Δ-Leu derivative are far from coplanarity, and a significant electronic conjugation of the π-orbital is likely to be rejected. 相似文献
45.
目的:构建表达小鼠轮状病毒(EDIM)EW株VP7基因的重组腺病毒,以在小鼠模型上研究轮状病毒的免疫保护机制。方法:用RT-PCR方法扩增EDIM VP7全长cDNA并进行基因序列分析,将所得的VP7基因片段插入腺病毒穿梭质粒pShuttle-CMV,获得重组质粒pShuttleCMV-EVP7,将该质粒与腺病毒骨架质粒pAdEasy-1共转化大肠杆菌BJ5183获得重组腺病毒质粒pAdCMV-EVP7,将该质粒线性化后转染293细胞包装重组腺病毒rvAdEVP7。以rvAdEVP7感染293细胞,并分别应用电子显微镜、PCR、RT-PCR和Western blot等方法观察rvAdEVP7的形态、VP7基因整合、遗传稳定性、VP7基因在细胞内转录及表达等有关生物学特性。结果:获得了小鼠轮状病毒的全长cDNA,重组腺病毒rvAdEVP7具有典型的腺病毒形态,PCR、RT-PCR和Western blot等分子生物学方法分析显示:rvAdEVP7中确有特异性的VP7基因稳定整合;有较好的遗传稳定性;感染293细胞后能有效转录;可表达轮状病毒主要结构蛋白VP7。结论:成功构建含VP7基因的重组腺病毒rvAdEVP7,为进一步研究轮状病毒的免疫保护机制打下了基础。 相似文献
46.
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48.
抗凝治疗肺心病血栓前状态的临床研究 总被引:6,自引:2,他引:4
目的探讨肺心病患者的血栓前状态,观察并分析低分子肝素抗凝干预的疗效。方法将54倒肺心病患者分为低分子肝素治疗组和常规治疗组各27例。分别检测治疗前后血浆血管性假血友病因子(VWF)、血浆凝血酶片段1 2(F1 2)、纤堆蛋白原(Fg)、血小板颗粒膜蛋白(GMP-140)和D-二聚体(DD)。结果肺心病患者VWF、F1 2、Fg、GMP-140、DD血浆浓度显著高于对照组;肺心病治疗组经LMWH治疗后上述各凝血分子标记物及PaCO2明显降低。而PaO2显著增高。常规组虽血气指标略有改善。但凝血分子标记物未见改善。结论尽早检测肺心病血栓前状态,及时给予低分子肝素抗凝干预,有望从根本上改善肺心病惠性加重期患者的不良预后。 相似文献
49.
E. Van de Keift K. De Boulle P. Willems J. -J. Martin P. Selosse B. Van der Auwera 《Acta neurochirurgica》1992,117(3-4):172-177
Summary Inactivation of tumour suppressor genes or anti-oncogenes as well as activation of dominant acting oncogenes seem to be important mechanisms in the pathogenesis of gliomas. We compared constitutional and tumoural genotypes at different restriction fragment length polymorphism loci (RFLP) on chromosomes 10 and 17 in 15 unrelated individualsLoss of heterozygosity (LOH) pointing to chromosomal loss or deletions was detected for at least one chromosme 17 marker in 11 gliomas (astrocytomas grades I–III and glioblastoma multiforme), whereas LOH for chromosome 10 loci was only detected in 3 out of 9 cases of glioblastoma multiforme and was not detected in low grade gliomas. Since LOH for chromosome 10 loci seems to be restricted only to glioblastoma multiforme, it is possible that recessive mutations on chromosome 10 are engaged in tumour progression from astrocytomas to glioblastoma multiforme. As LOH of chromosome 17 markers occurs in astrocytomas as in glioblastoma multiforme, chromosome 17 loci probably are involved in early tumour development. 相似文献
50.
Summary Light and scanning electron microscopical examination and molecular analysis of pinworm samples collected from the Sumatran
orangutan (Pongo abelii) from Sumatra (Indonesia) revealed the presence of a new taxon, Pongobius hugoti gen. et sp. n. (Oxyuridae: Enterobiinae). The monotypic genus Pongobius is characterised by the presence of a triangular mouth, three rounded teeth and three chisel-like inner teeth in the buccal
cavity, an oesophagus with a long pharyngeal part, corpus posteriorly slightly enlarged and continuing as a pyriform bulb,
isthmus absent. These features differentiate P. hugoti from all members of the subfamily Enterobiinae. The male has a long caudal appendix (> 50% of total tail length). Molecular
analysis of the new taxon is presented for more precise identification. 相似文献