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Objectives

Ischemic stroke is influenced by both environmental and genetic factors. The CD40/CD40L system is related to proinflammatory and prothrombogenic responses, which are involved in the pathophysiology of ischemic stroke. The aim of this study was to evaluate association between the CD40 -1C/T single nucleotide polymorphism (SNP) and ischemic stroke in a Chinese population.

Methods

We conducted a case–control study including 286 ischemic stroke patients and 336 controls. CD40 -1C/T SNP was genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and DNA sequencing methods, and evaluated its relevance to ischemic stroke susceptibility.

Results

Significantly increased ischemic stroke risk was found to be associated with the T allele of CD40 -1C/T (OR = 1.273, 95% CI = 1.016–1.594). The frequencies of CT and TT/CT genotypes of CD40 -1C/T in ischemic stroke patients were significantly higher than those of controls, respectively (for CT: OR = 2.350, 95% CI = 1.601–3.449; for TT/CT: OR = 2.148, 95% CI = 1.479–3.119). And, similar results were obtained after adjusting non-matched variables. We found that the frequency of carried T genotypes (TT and TT/CT) was significantly increased in patients with history of stroke compared with patients without (for TT: OR = 6.538, 95%CI = 1.655–25.833; for TT/CT: OR = 3.469, 95%CI = 1.031–11.670), respectively.

Conclusions

The findings suggested that the CD40 -1C/T polymorphism might contribute to the susceptibility to ischemic stroke in the Chinese population, and might be associated with history of previous stroke.  相似文献   
3.
湖南鹅膏属(蘑菇目)标本的订正   总被引:5,自引:0,他引:5  
对采于湖南现存湖南师范大学真菌标本室 (MHHNU)和中国科学院微生物研究所真菌标本室 (HMAS)的鹅膏属标本进行了研究 ,发现有不少标本鉴定有误 ,需要订正。本文对 16种鹅膏的分类问题进行了讨论 ,对鲜为人知的湖南鹅膏A hunanensis进行了详细描述。湖南鹅膏隶属于橙盖鹅膏组sect.Caesareae ,其主要特点是担子果中等至大型 ;菌盖灰色至褐色 ,具深色花斑 ,边缘有较长的沟纹 ;菌褶白色 ,褶缘灰褐色 ;菌柄有菌环、被蛇皮状灰褐色鳞片 ;菌托白色 ,其中含有丰富的膨大细胞 ;担子基部有锁状联合 ;担孢子椭圆形 ,非淀粉质 ,(8 0 ) 9 5~ 12 5 (15 5 )× 6 5~ 8 5 (10 0 ) μm。  相似文献   
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5.
中国清风藤属Sabia Colebr.(清风藤科)的订正   总被引:7,自引:0,他引:7  
归并了清风藤属5个名称,Sabia campanulata Wall.ex Roxb.var,kingiana Nayar et Majumder处理为S.campanulata Wall.ex Roxb。的异名,S.metcalfiana L.Chen处理为S.leptandra Hook.f.et Thoms.的异名,S.longruiensis X.X.Chen et D.R,Ling和S.swinhoei Hemsl.ex Forbes et Hemsl.ex FOrb.et Hemsl。的异名,S.nervosa Chun ex Y.F.Wu处理为S.coriacea Rehd.et Wils.的异名,订正了缅甸清风藤S.burmania L.chen在中国有分布的错误报道。  相似文献   
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Heroine cichlids are the second largest and very diverse tribe of Neotropical cichlids, and the only cichlid group that inhabits Mesoamerica. The taxonomy of heroines is complex because monophyly of most genera has never been demonstrated, and many species groups are without applicable generic names after their removal from the catch-all genus Cichlasoma (sensu Regan, 1905). Hence, a robust phylogeny for the group is largely wanting. A rather complete heroine phylogeny based on cytb sequence data is available [Concheiro Pérez, G.A., Říčan O., Ortí G., Bermingham, E., Doadrio, I., Zardoya, R. 2007. Phylogeny and biogeography of 91 species of heroine cichlids (Teleostei: Cichlidae) based on sequences of the cytochrome b gene. Mol. Phylogenet. Evol. 43, 91–110], and in the present study, we have added and analyzed independent data sets (nuclear and morphological) to further confirm and strengthen the cytb-phylogenetic hypothesis. We have analyzed a combined cytb-nuclear (RAG1 and two S7 introns) data set of 48 species representing main heroine lineages to achieve further resolution of heroine higher taxonomic levels and a combined cytb-morphological data set of 92 species to stabilize generic taxonomy. The recovered phylogenies supported the circumamazonian—CAM—Heroini (sensu Concheiro Peréz et al., 2007) as a monophyletic group, that could be divided into six main clades: (1) australoheroines (the southernmost heroine genus Australoheros), (2) nandopsines (the Antillean genus Nandopsis), (3) caquetaines (including the north western Amazonian genera Caquetaia and Heroina), (4) astatheroines (including Astatheros, Herotilapia and Rocio), (5) amphilophines (including Amphilophus and related genera), and (6) herichthyines (including Herichthyis and related genera). Nuclear and mitochondrial data partitions arrived at highly congruent topologies. Suprageneric relationships were influenced mainly by the nuclear signal, as well as the most basal phylogenetic position of Australoheros within CAM heroines. The new phylogeny of the tribe Heroini provides robust framework to stabilize the taxonomy of the group and for future comparative studies on these morphologically and ecologically diverse freshwater fishes. Morphology was mostly informative at the genus level and aid in determining the monophyly and composition of heroine genera. Upon acceptance of all putative genera, as recovered in this study, the Heroini would be with 35 genera the most genus-rich clade of Neotropical cichlids.  相似文献   
8.
The Permian suborder Protanisoptera (Insecta: Odonatoptera) is revised and a new phylogenetic hypothesis proposed after analyses based on wing venation and different outgroups. After our study the families Camptotaxineuridae and Kaltanoneuridae are excluded from the Protanisoptera. After a new phylogenetic analysis, the family Permaeschnidae is redefined and the families Pholidoptilidae, Polytaxineuridae, Callimokaltaniidae and Hemizygopteridae are restored, as already proposed for the latter three families by Bechly (1996). The new genus Proditaxineura is described. The genus Gondvanoptilon RÖSLER et al., 1981 is excluded from the Meganisoptera: Erasipteridae and re-included in the Permaeschnidae, as already proposed by Bechly (1998). Permaeschna proxima MARTYNOV, 1931 is considered as a junior synonym of Permaeschna dolloi MARTYNOV, 1931. Pholidoptilon camense ZALESSKY, 1931 is excluded from Permaeschna MARTYNOV, 1931 and the genus Pholidoptilon [Zalessky, 1931a] and [Zalessky, 1931b] is restored. Ditaxineurella stigmalisMARTYNOV, 1940 is excluded from the Hemizygopteridae and considered as a Protanisoptera Incertae sedis.  相似文献   
9.
比较研究单种属,槽稃草属EuthryptochloaCope与显子草属PhaenospermaMunro的叶表皮微形态,并结合外部形态特征说明槽稃草属与显子草属无论在叶表皮微形态或外部形态上都无区别。根据国际植物命名法规的优先律,槽稃草属不能独立成属,应归入显子草属  相似文献   
10.
在编写《中国沙漠植物志补编》过程中,发现我国有角果毛茛属植物2种,弯喙角果毛茛,为我国分布新记录,角果毛茛名称有误,应订正。  相似文献   
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