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861.
862.
Abstract Haloxylon ammodendron (C. A. Mey.) Bunge is a host for the holoparasitic plant Cistanche deserticola Y. C. Ma, the original source of medicinal material known as Herba Cistanchis. The inter‐simple sequence repeat marker was used to assess the genetic variations and relationships among six accessions of H. ammodendron with a total of 120 individuals collected from three localities in the Alxa Desert, Inner Mongolia, China. At each locality, individuals both parasitized (PP) by C. deserticola and non‐parasitized (NP) were sampled. The results showed that Nei's gene diversity and Shannon's index of PP accessions were higher, but were not significantly different, from those of NP accessions. An unweighted pair‐group method arithmetic average dendrogram showed two clusters, one that included all PP accessions, and the other the NP accessions. Genetic differentiation therefore existed between PP and NP accessions, which might be attributed to low gene flow between the NP and PP groups (Nm<1). However, the relationship between genetic distance and geographic distance within each group, although not statistically significant in this study, might be associated with high gene flow in both the NP and PP groups.  相似文献   
863.
The genus Copidosoma (Hymenoptera: Chalcidoidea: Encyrtidae) is a diverse group of polyembryonic parasitoids of Lepidoptera, including species that have the potential to control agricultural and forestry pests. Moreover, some species of Copidosoma display polyembryony. Despite their economic and scientific importance, little is known about the phylogeny of Copidosoma and its relations to other groups of Encyrtidae. Here we infer the phylogenetic relationships of this genus from nucleotide sequences of two nuclear (18S and 28S) and one mitochondrial (COI) genes. Forty‐four species of Copidosoma and three species of Copidosomopsis plus two outgroup species are included in Maximum Parsimony and Bayesian analyses. Copidosomopsis syn. n . is proposed as a junior synonym of Copidosoma based on phylogenetic analysis results. Each of nine identical clades, resulting from both analyses, is proposed as informal species group: cervius group (cervius, chalconotum and serricorne), recovered as the basal lineage of Copidosoma; nacoleiae group (nacoleaie, meridionalis and an undescribed species, formerly belonging to the genus Copidosomopsis); boucheanum group (boucheanum, terebrator, peticus, phaloniae, ancharus, tibiale and sosares); noyesi group (noyesi and probably undescribed related species); albipes group (albipes and coimbatorense); varicorne group (including varicorne and subalbicorne in one subclade, and aretas and fuscisquama in the other); thebe group (thebe and probably undescribed related species); exiguum group (exiguum and probably undescribed related species); floridanum group (floridanum, primulum, transversum, truncatellum and agrotis). Host associations of the genus and host specificity of recognized groups are discussed. The current work offers a foundation for a comprehensive phylogeny of Copidosoma and the possibility to reconstruct cophylogeny between Copidosoma and their lepidopteran hosts.  相似文献   
864.
青海省南部治多-杂多一带早石炭世有孔虫动物群   总被引:2,自引:0,他引:2  
在青海省南部的治多—杂多一带1/25万地质填图中,于杂多群中首次发现非筵有孔虫,建立2个组合,即Endothyra-Mediocris—Archaediscus组合和Bradyina-Endothyranopsis组合,地质时代为早石炭世大塘期德坞期,与华南、塔里木盆地、西秦岭、前苏联等地同期生物群可很好地对比,同时结合大冢相似系数的计算表明,青海南部地区在早石炭世属于特提斯大区华夏生物区华南省。  相似文献   
865.
报道以红皮病为突出表现AIDS 1例.患者男性,64岁,因“全身发疹2个月,伴发热1周”收入院.查体发现体重明显下降,双睑结膜充血,口腔上颚,颊黏膜密集点滴状白色伪膜,全身弥漫暗红色斑片,伴有褐色痂皮脱屑.口腔黏膜真菌涂片(+),HIV-1(+).确诊AIDS,红皮病,口腔念珠菌感染.后死于肺部感染.  相似文献   
866.
目的 观察红色毛癣菌刺激人角质形成细胞后γ-IFN及IL-8浓度的变化,以及TLR2对γ-IFN和IL-8分泌的影响.方法 用红色毛癣菌悬液分别刺激TLR2抗体处理前后的角质形成细胞,采用ELISA方法检测不同时间点细胞上清液中γ-IFN及IL-8的浓度,并设置阴性对照;比较TLR2抗体处理的后γ-IFN及IL-8浓度的变化.结果 红色毛癣菌刺激角质形成细胞后,γ-IFN及IL-8浓度明显升高(P<0.05),4h即开始,至16 h达高峰;用TLR2抗体中和TLR2后,上清液中IL-8的浓度在2h、4h、8h、16h各时间点较中和前低,差异有统计学意义(P<0.05);γ-IFN的浓度2h、4h、8h时间点较中和前低,差异有统计学意义(P<0.05),而在16h时间点,上清液中γ-IFN的浓度与中和前比较略低,但差异没有统计学意义(P>0.05).结论 红色毛癣菌刺激角质形成细胞后,可促进角质形成细胞分泌γ-IFN和IL-8;TLR2在角质形成细胞分泌γ-IFN和IL-8的过程中发挥重要的调节作用.  相似文献   
867.
Haloxylon ammodendron (C. A. Mey.) Bunge is a host for the holoparasitic plant Cistanche deserticola Y. C. Ma, the original source of medicinal material known as Herba Cistanchis. The inter-simple sequence repeat marker was used to assess the genetic variations and relationships among six accessions of H. ammodendron with a total of 120 individuals collected from three localities in the Alxa Desert, Inner Mongolia, China. At each locality, individuals both parasitized (PP) by C. deserticola and non-parasitized (NP) were sampled. The results showed that Nei's gene diversity and Shannon's index of PP accessions were higher, but were not significantly different, from those of NP accessions. An unweighted pair-group method arithmetic average dendrogram showed two clusters, one that included all PP accessions, and the other the NP accessions. Genetic differentiation therefore existed between PP and NP accessions, which might be attributed to low gene flow between the NP and PP groups (Nm< 1). However, the relationship between genetic distance and geographic distance within each group, although not statistically significant in this study, might be associated with high gene flow in both the NP and PP groups.  相似文献   
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