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201.
202.
Huadan Ye Xiaojing Li Lingyan Wang Qi Liao Leiting Xu Yi Huang Liming Xu Xuting Xu Cheng Chen Hangyu Wu Yanping Le Qiong Liu Meng Ye Changzheng Dong Shiwei Duan 《Gene》2013
Aims
The aim of this study was to evaluate the combined contribution of 12 genetic variants to the risk of coronary heart disease (CHD).Methods
Through a comprehensive literature search for genetic variants involved in the CHD association study, we harvested a total of 10 genes (12 variants) for the current meta-analyses. These genes consisted of GPX1 (rs1050450), PPARD (rs2016520), ALOX15 (rs34210653), SELPLG (rs2228315), FCGR2A (rs1801274), CCL5 (rs2107538), CYP1A1 (rs4646903), TP53 (rs1042522), CX37 (rs1764391), and PECAM1 (rs668, rs12953, and rs1131012).Results
A total of 45 studies among 23,314 cases and 28,430 controls were retrieved for the meta-analyses of 12 genetic variants. The results showed a significant association between the GPX1 rs1050450 polymorphism and CHD (odd ratio (OR) = 1.61, 95% confidence interval (CI) = 1.25–2.07, P = 0.0002). Other meta-analyses of the rest 11 variants suggested a lack of association with the risk of CHD.Conclusion
Our results confirmed that GPX1 rs1050450 was associated with susceptibility to CHD in Chinese and Indian populations. 相似文献203.
To investigate the influence of the interleukin-10 gene promoter polymorphisms on the susceptibility of endometriosis, we examined the association by performing a meta-analysis. The PubMed, Embase, HuGE Navigator and CNKI were searched to identify eligible studies. We then conducted a meta-analysis to examine the association between interleukin-10 gene promoter polymorphisms and endometriosis. Eight case–control studies which examined the association between the IL-10 gene promoter polymorphisms and the susceptibility to endometriosis were finally included in the meta-analysis. Meta-analysis of the IL-10 − 592 A/C polymorphisms showed a significant increased risk of endometriosis in the overall and Asian population in all genetic models and allele contrast. However, meta-analysis of the IL-10 − 1082 A/G and IL-10 − 819 T/C polymorphisms showed no association with endometriosis in all genetic models and allele contrast in the overall and Asian population samples. In addition, there was not a significant association between the IL-10 − 592 A/C gene promoter polymorphisms with the severity of endometriosis. 相似文献
204.
205.
中国淡水鱼类人工增殖放流现状 总被引:15,自引:0,他引:15
随着鱼类资源的持续衰退以及保护水产学的兴起,鱼类人工增殖放流已由传统渔业增殖发展成为特有珍稀鱼类种群恢复的主要技术手段。近年来,我国淡水鱼类人工增殖放流涉及水系多、规模大且种类丰富,取得了显著效果并积累了大量基础资料和经验。为深入开展人工增殖放流基础研究,规范技术并提升生态效益,该文收集整理了国内、外相关文献资料,分别从基础理论、塘养种群管理及效果评价等方面阐述人工增殖放流的理论背景,并结合我国"四大家鱼"、中华鲟、胭脂鱼、滇池金线鲃及其他珍稀濒危鱼类人工增殖放流现状,讨论了野外监测和效果评价的作用和意义,提出放流种群遗传局限性、数量和规格权衡以及经济效益与生态效益权衡等问题,旨在为相关研究和人工放流实践提供系统资料。 相似文献
206.
A partial skeleton of a new pterosaur, Jianchangnathus robustus gen. et sp. nov. from western Liaoning, China, is described. The specimen (IVPP V16866) was collected near Linglongta, Jianchang County, whose deposits have a disputed age that range from Middle Jurassic to Early Cretaceous. The new species shares several features with the non-pterodactyloid Scaphognathus from the Late Jurassic deposits of southern Germany, such as a deep anterior end of the lower jaw, a piriform lower temporal fenestra with the ventral margin broader than the dorsal one and the interalveolar spacing of the maxillary teeth about three alveolar spaces, allowing its allocation to the Scaphognathidae. The main diagnostic features of J. robustus include the large maxillary process of the jugal, the convex alveolar margin of the lower jaw and the procumbent disposition of the first three pairs of dentary teeth. The new Chinese taxon also differs from Fenghuangopterus lii, which comes from the same deposit and is here regarded as Scaphognathidae incertae sedis, mainly by the lower number of teeth and several proportions of the wing elements. The discovery of J. robustus demonstrates a larger diversity in the pterosaur fauna of the Linglongta region so far dominated by the non-pterodactyloid clade Wukongopteridae. 相似文献
207.
The Recent volutids Cymbiola and Melo burrow in a forward direction. This agrees well with the spiral terrace pattern observed in Eocene Volutidae, thus strengthening the idea that they were forward burrowers as well. The presence of collabral terraces near the aperture in the Cassidae suggests an oblique burrowing direction, by convergence with the Nassariidae. This is confirmed by observations on living cassids. The sutural canals and associated structures of the Olividae and Seraphidae are functional in detecting whether the posterior region of the shell is buried. This confirms the idea that fossil Strombidae possessing similar features were burrowers. In contrast with these “predictable”; observations, burrowing was observed in a few gastropods the shell morphology of which would seem to exclude such behaviour, such as Architectonica, Cymatium, Volema and Bolinus. Thus, a few morphologic criteria appear to be reliable and of general applicability in inferring burrowing habits in gastropods. At the same time, the broad variety of burrowing mechanisms and life habits of gastropods makes it unlikely that general criteria will ever be found to exclude burrowing habits on the basis of shell morphology. 相似文献
208.
A new specimen of Philydrosaurus proseilus from the Early Cretaceous Chiufotang (Jiufotang) Formation preserves the first complete palate of a monjurosuchid choristodere. As in other choristoderes, the palate of Philydrosaurus is akinetic, extended by a broad contact between the vomer and maxilla, and equipped with multiple batteries of palatal teeth. This specimen provides phylogenetically significant information and clarifies the distribution of many apomorphies within Choristodera. Philydrosaurus is primitive relative to the Neochoristodera in that it exhibits only a moderate degree of posterior displacement of the choanae and retains a relatively large interpterygoid vacuity. However, Philydrosaurus also exhibits several derived features previously considered diagnostic of the Neochoristodera, including establishment of a long midline contact of the pterygoids and development of a distinct nasopalatal trough extending from the choana. The choristodere palate exhibits significant modification of the primitive diapsid condition, including elongation of the vomers, establishment of a vomer–maxilla contact, posterior displacement of the choanae, development of the nasopalatal trough, and reduction of the interpterygoid vacuity. 相似文献
209.
Abstract: Two new genera with six new species of hangingflies (Mecoptera: Raptipedia: Cimbrophlebiidae) are described. They were collected from the Middle Jurassic nonmarine sedimentary strata of the Jiulongshan Formation in Daohugou, Inner Mongolia, north‐eastern China. This report of Cimbrophlebiidae from the Yanliao Biota provides detailed morphological information and evidence of a broad diversity of Cimbrophlebiidae during the Middle Jurassic. A key to the known species of Cimbrophlebiidae is provided. 相似文献
210.
Diversity and abundance of ammonia-oxidizing archaea (AOA) and bacteria (AOB) in samples of the northern South China Sea subsurface sediment were assessed by analyzing the amoA gene sequences retrieved from the samples. The microbial diversity was assessed using rarefaction and phylogenetic analyses. The deep-sea subsurface sediments harbored diverse and distinct AOA and AOB communities, but the abundance of AOA was lower than that of AOB, consistent with many other studies about bacteria and archaea in subsurface sediments. Diversity of AOA shown in the OTUs and Shannon index was correlated with the concentration of nitrite in the Pearson analysis, but no obvious relationships between the diversity or abundance of AOB and the physicochemical parameters could be identified in the present study, indicating the concentration of ammonium may not be an important factor to determine the diversity and abundance of ammonia-oxidizing prokaryotes in the subsurface sediments. Additionally, Nitrosomonas-like AOB was found to be dominant in subsurface sediments of the northern South China Sea showing a different adaption strategy comparing with some Nitrosospira-like AOB lineages. Concentration of nitrite was correlated with diversity of AOA, but no correlations between diversity and abundance of AOB and the physicochemical parameters were established in the study. Supplementary materials are available for this article. Go to the publisher's online edition of Geomicrobiology Journal to view the free supplemental files. 相似文献