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Moth monitoring in a coniferous forest in southwestern Korea was carried out for 3 years in order to investigate the effects of winter weather factors on moth survival and emergence in early spring. A total of 686 individuals in 51 species of 4 families were collected during 3 spring sampling periods. The species richness observed for all 3 years was similar, though their abundance was differed. A total of 15 weather variables were analyzed including temperature and precipitation during the 4 months preceding April, and cumulative sums of 5-degree days with base temperatures ranging from 6 to 10 °C. Due to the multicollinearity of dependent variables, we adopted the eigenvectors of major axes from principal component analysis for multiple stepwise regression analysis. The species richness and abundance were significantly related to the first and second axes. Both axes were positively related with precipitation and temperature during the preceding 2 months, as well as the average winter temperature. This indicated that the effects of temperature and precipitation during winter played an important role in moth emergence in early spring, though the weather conditions of each month during winter varied significantly compared to the pattern of adult emergence.  相似文献   
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This is the first report of occurrence of Vespa velutina Lepeletier from Korea. The diagnosis and taxonomic relationship between geographical subspecies is provided, with a revised key to complement the previous taxonomic information of Korean Vespa species. The ecological aspect of the species is also discussed.  相似文献   
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他汀类药物可上调内皮一氧化氮合酶(ENOS)的表达,并由甲羟戊酸(MVA)途径介导,但具体机制未完全阐明.本研究旨在探索洛伐他汀(LVT)上调ENOS表达的分子信号机制并明确同ENOS表达相关的顺式作用元件的定位.洛伐他汀通过减少细胞内固醇,如MVA和geranylgeranyl pyrophosphate (GGPP),从而增加ENOS mRNA的稳定性.因GGPP是细胞内信号蛋白如Ras、Rho GTPase进行翻译后修饰和膜定位所必需的,因此很可能洛伐他汀的作用与细胞内信号途径有关.进一步的实验结果显示Rho激酶抑制剂 hydroxyfasudil和细胞松弛素D均可在转录后水平上调ENOS mRNA表达,表明Rho途径介导的细胞骨架状态在ENOS mRNA降解率的调控中起一定作用. 细胞转染实验证明调控ENOS mRNA 降解的顺式作用元件位于其mRNA序列上的3′未翻译区(3′UTR)和相邻的编码区.其中调控GGPP介导ENOS mRNA稳定性的顺式作用元件位于序列的3 751~4 606位点间;而hydroxyfasudil通过位于3 751~ 4 468位点间的顺式作用元件稳定ENOS mRNA;细胞松弛素D通过位于3 904~4 188位点间的元件稳定ENOS mRNA.洛伐他汀可能通过抑制Rho激酶途径稳定ENOS mRNA,此过程由位于mRNA序列上3′UTR及相邻编码区的多样顺式作用元件介导.另外,细胞骨架的空间构造也可影响ENOS mRNA的稳定性,此过程由位于其mRNA序列编码区的顺式作用元件介导.本研究为转录子稳定性调控机制的进一步研究提供了有力根据,或许可为心血管疾病的治疗提供新的分子靶点.  相似文献   
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罗容  吴霞  李静宜  崔湖荣  张楠  张贵君 《生物磁学》2012,(32):6228-6233
目的:研究枳实提取物及其药效组分橙皮苷和新橙皮苷对氧化低密度脂蛋白(oxidized lowd ensity lipoprotein,Ox—LDL)损伤的人脐静脉内皮细胞(human umbilical vein endothelial cells line,HUVEC)细胞间黏附分子-1(intercellular adhesion molecule-1,ICAM-1)表达和一氧化氮(nitric oxide,NO)释放的影响。方法:体外培养HUVEC,50μg/mLOX—LDL制造HUVEC损伤模型。以MTS染色法检测细胞毒性确定用药浓度。细胞ELISA法测定细胞表面ICAM-1的含量,试剂盒测定细胞培养上清液中NO含量。结果:①枳实提取物小于等于2mg/mL时,橙皮苷浓度小于等于0.03125mg/mL时,新橙皮苷浓度小于等于0.25mg/mL时,HUVEC存活率分别大于80%。②2.0mg/mL和1.0mg/mL两个浓度的枳实提取物、15.625μg/mL的橙皮苷和0.2500mg/mL新橙皮苷对OX—LDL诱导的HUVEC的ICAM-1表达有显著抑制作用。③2.0mg/mL枳实提取物显著提高OX—LDL诱导的HUVEC和正常HUVEC培养液中的NO含量;7.813ixg/mL、15.625μg/mL和31.250μg/mL 3个浓度的橙皮苷能显著提高OX—LDL诱导的HUVEC培养液中的NO含量,31.250μg/mL的橙皮苷能促进正常HUVEC的NO释放;0.2500mg/mL和0.1250mg/mL 2个浓度的新橙皮苷能显著提高OX—LDL诱导的HUVEC培养液中的NO含量。结论:枳实提取物及其药效组分橙皮苷、新橙皮苷能抑制Ox-LDL诱导的HUVEC的ICAM-1表达,促进Ox-LDL诱导的HUVEC的NO释放。  相似文献   
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Moth assemblages in three habitat types were investigated to find differences in species richness and abundances and to find any specific moth group(s) in each habitat. Study areas were in southern Korea: lowlands of Muan-county, Jeollanam-do Province and mid-elevations to highlands of Mt. Jirisan National Park. Moth monitoring, conducted at eight sites, was comprised of three habitat types—native forest, regenerative forest and rural landscape. A total of 4,803 individuals, consisting of 583 species in 362 genera, were identified. Species richness did not differ significantly by habitat type or elevation. ANOVA indicated that site, location and elevation significantly affected the species abundances of Drepanidae, Epiplemidae, Limacodidae, Noctuidae and Zygaenidae, while habitat type was not a significant factor. The moth abundances of Geometridae, Lasiocampidae, Lymantriidae, Notodontidae, Saturniidae, Sphingidae and Thyatiridae were not significantly associated with any independent variables. The diversity patterns of larger moths along environmental gradients and the relationship between moths and forest types were discussed.  相似文献   
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We investigated the spatial patterns in the distribution of carrion beetles on 26 islands to test the area and distance effects on species diversity. The relationships between species richness and assemblage and island area, distance from the mainland, and shortest distance from the largest island within 2?km were analyzed using linear regression, Canonical Correspondence Analysis (CCA) and Multi-Response Permutation Procedures (MRPP). We hypothesized that both area and distance from the mainland played a significant role in species richness, while geographic location in the sea influenced aggregation of carrion beetles on islands. Area was the only factor influencing species richness of carrion beetles on islands. Moreover, distance from the mainland and close islands did not significantly influence to carrion beetles. In addition, geographic location in the same Sea did not influence beetle assemblages. Taken together, the results of this study indicated that carrion beetles on Korean islands were largely affected by island size and that dispersal was stochastic.  相似文献   
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