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881.
Xu‐Mei WANG Dong‐Ye YANG Yong‐Zhen TIAN Peng‐Fei TU Qi‐Shi SUN Xiao‐Bo LI 《植物分类学报:英文版》2009,47(3):255-262
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
882.
FANG YU FU‐QIANG CHEN SHEN‐HORN YEN LI‐HONG TU CHAO‐DONG ZHU EMILIO GUERRIERI YAN‐ZHOU ZHANG 《Systematic Entomology》2014,39(2):325-334
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
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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
887.
土壤溶液被称作"土壤的血液",是土壤中各种生物化学反应的中介物质,在外界环境发生变化时,土壤溶液化学成分能在其他土壤指标尚无变化之前对环境变化做出迅速响应。为了探索持续增加的大气氮(N)沉降对森林生态系统的影响,以华西雨屏区亚热带常绿阔叶林为对象,设置对照(CK,0 g m-2 a-1),低N(LN,5 g m-2 a-1),高N(HN,15 g m-2 a-1)三种N处理,通过人工施加硝酸铵(2017年9月起改施硝酸钠及氯化铵)的方法模拟N沉降增加情景,N处理42个月后,使用负压土壤溶液采样器定位收集A层(37-45 cm)及B层(52-60 cm)土壤溶液,并进行分析(每月1次,为期1 a)。结果表明:对照处理中A、B两层土壤溶液NO3-浓度达(3.94±0.77)mg/L、(4.27±1.13)mg/L,N添加显著提高两层土壤溶液NO3-浓度和B层NH4+浓度;N添加显著降低土壤溶液pH,且显著增加Al3+浓度,Ca2+和Mg2+含量有增加趋势,但影响不显著;N处理使A层土壤溶液可溶性有机碳(DOC)浓度显著降低,对两层土壤溶液芳香化指数(AI)无显著影响;两层土壤溶液电导率(EC)及氧化还原电位(Eh)显著增加;此外,两层土壤溶液中许多化学成分均呈现极显著相关,特别是NO3-与EC相关系数达到了0.855。本研究中,对照处理极高的NO3-含量以及B层土壤溶液硝酸盐浓度高于A层,表明该亚热带常绿阔叶林N的有效性超过植物和微生物的总营养需求而发生淋溶,该生态系统已达到氮饱和状态,此外N添加会显著促进土壤酸化和铝离子活化,表层土壤溶液DOC的降低一定程度反映了凋落物分解受N添加的抑制作用,显著升高的氧化还原电位可能导致土壤中某些金属元素的迁移率降低。 相似文献
888.
【背景】以流式细胞技术为代表的高通量筛选技术能够高效筛选具有目标性状的微生物工程菌株。在流式分选中微生物的粘连会造成分析数据不准确,分选纯度降低,因此快速简便的单细胞样品制备是流式检测的关键。优势菌大多是通过筛选偶联荧光蛋白的随机突变库获得,阳性率低,杂质和死细胞的自发荧光较强,容易混入分选门内造成存活率降低,亟须提高分选存活率的方法。【目的】建立一种简便的微生物流式分选的单细胞样品制备方法,并通过碘化丙啶(propidium iodide, PI)染色提高分选样品存活率。【方法】分别在大肠杆菌、枯草芽孢杆菌、谷氨酸棒状杆菌和酵母菌4种底盘细胞中探索超声波、消化酶、表面活性剂及超声-表面活性剂联合作用4种方式对单细胞制备效率的影响。提高微生物流式分选存活率,用常压室温等离子诱变(atmospheric and room temperature plasma, ARTP)技术处理含有绿色荧光蛋白(green fluorescent protein, GFP)的酿酒酵母HZ848 (简称HZ848-GFP),形成不同强度GFP文库后,按照GFP强度分选全细胞和PI染色阴性细胞的前0.5%,统计单细胞存活率。【结果】酵母细胞分散条件为:0.01% Tween-80联合超声1 min,单细胞率达到88%以上,PI染色细胞破损率<1.4%。谷氨酸棒状杆菌单细胞分散条件为:0.01% Tween-80联合超声5 min,单细胞率达到97%以上,PI染色细胞破损率<1%。分选存活率结果表明,未用PI染色的酿酒酵母分选后单细胞存活率是4.3%,用PI染色去除死细胞后再分选单细胞存活率是18.3%,后者是前者的4.3倍,且具有显著性差异。【结论】本研究为微生物流式分选建立了一套简单快捷的单细胞样品制备方法,证实了PI染色法能够显著提高分选样品存活率。 相似文献
889.
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
890.
Yu-qin Li Tao Xue Liang Wang Zu-cai Xu Zhi-qin Xi Jie Yuan Xue-feng Wang Yang-mei Chen Meilin Zhang Lan Yao 《Neurochemical research》2009,34(9):1594-1602
Epithelial membrane protein-1 (EMP-1), called Tumor-associated membrane protein, is the marker of a drug-resistant tumor and
take part in the drug-resistant mechanism of tumor, with the relationship of epidermal growth factor receptor (EGFR). Because
there are some similarities between the pathogenesis and the drug resistance mechanism of tumor and the drug resistance mechanisms
in epilepsy. EMP1 expression may be connected with the drug-resistance mechanism of epilepsy. We detected EMP-1 by gene scanning
and immunohistochemistry staining, comparing the IE group and the control group, and we investigated the relationship between
EMP-1 and EGFR by double-label immunofluorescence staining in the IE group. We found expression of EMP-1 mRNA was higher in
IE per the gene scanning, EMP-1 immunoreactivity was apparent in neurons of IE patients but not in the control group, and
the expression of EMP-1 and EGFR occurred in the same neuron. We confirm EMP-1 is abnormally expressed in IE and suggest the
interaction of EGFR and EMP-1 plays a role in the mechanism of drug resistance in epilepsy and may be a new gene for drug
resistance. 相似文献