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161.
Functional morphology of antennal chemoreceptors of the parasitoid Microplitis croceipes (Hymenoptera: Braconidae) 总被引:5,自引:0,他引:5
The specialist parasitoid, Microplitis croceipes (Cresson) (Hymenoptera: Braconidae), uses chemical cues from plants damaged by herbivore-feeding and also plant by-products in host location and acceptance. These chemicals are detected by the wasp's antennae. We conducted scanning and transmission electron microscopy studies of male and female M. croceipes antennae and detected no distinct morphological differences in the chemoreceptors between the sexes. Male antennae are approximately twice as long as female antennae. We found five morphological sensillar types in both sexes: sensilla (s) trichodea were the most abundant and distributed over the whole antenna; s. chaetica were present in low numbers only on the scape and pedicel; and s. basiconica, s. coeloconica and elongated s. placodea were found only on the flagellum. Ultrastructural investigations revealed pore systems on s. basiconica and s. placodea. In s. placodea, sensory neurons run parallel to the longitudinal axis of the sensilla with terminal pores. We recorded responses from single olfactory receptor neurons in s. placodea to two plant-emitted volatiles, cis-3-hexenol and ocimene, and two anthropogenic compounds, cyclohexanone and 2-diisopropylaminoethanol. Male receptor neurons were more sensitive than those of females with significantly higher spike frequency being registered from neurons in males. 相似文献
162.
163.
V Furtak F Hatcher J Ochieng 《Biochemical and biophysical research communications》2001,289(4):845-850
Galectin-3, a beta-galactoside binding lectin, has been demonstrated to play a key role(s) in cell to extracellular matrix interaction. The precise mechanism by which it modulates cellular adhesion is presently unclear and warrants further studies. We hereby report that galectin-3 mediates the endocytosis of beta-1 integrins in a lactose-dependent manner. Interestingly we observed that galectin-3 was also rapidly internalized by the cells via the same pathway and the internalization was completely blocked by lactose. The endocytosis process was temperature dependent and was inhibited by filipin but not chlorpromazine. The endocytosis of galectin-3 and beta-1 integrins by the cells was accompanied by rapid cell spreading due to cytoskeletal reorganization. The data suggest a novel mechanism by which galectin-3 and beta-1 integrins are internalized into breast carcinoma cells via a cavaleolae-like pathway of endocytosis. 相似文献
164.
豆科黄结属模式及其相关种名的考证 总被引:4,自引:0,他引:4
长期以来,Termopsis lanceolata R.Br.被误认为是黄华属的模式。根据有关文献考证和国际植物命名法规,作者为认T.;lanceoltata是一个不合法名,黄华属的合法模式应为Thermopsis Lupinoides(L.)Link.分布于东北亚,花具互生花的黄华长期被误定为T。lupinoides(L.)Link,应更正为Thermopsis fabacea(Pall)DC.。 相似文献
165.
BACKGROUND: By 2016, the proportion of Canadians older than 65 years of age will increase to 16%, and there will be an increase in the absolute number of cases of cardiovascular disease in older Canadians. The Canadian Heart Health Surveys database provides information about this population upon which health policy related to cardiovascular disease can be based. This paper presents for the first time population-based data on the risk factors for cardiovascular disease in older Canadians. METHODS: Canadians from all 10 provinces participated in surveys of cardiovascular risk factors; health insurance registries were used as sampling frames. In each province, probability samples of 2200 adults 18 to 74 years old not living in institutions, on reserves or in military camps were asked to participate in interviews and to undergo testing at clinics for major risk factors for cardiovascular disease. RESULTS: A total of 2739 men (response rate 70%) and 2617 women (response rate 66%) aged 55 to 74 years participated in the survey and also provided follow-up clinical measurements at the clinic. Overall, 52% of participants were hypertensive, 26% had isolated systolic hypertension, and 30% had a total blood cholesterol level of 6.2 mmol/L or greater. Rates of current smoking were lower in women than men (17% v. 22%). Overall, 87% of men and 78% of women who were current smokers smoked at least 10 cigarettes per day. Only slightly more than half of participants exercised at least once a week for at least 15 minutes, and almost half had a body mass index of 27 or greater. In only 4% was no major risk factor for cardiovascular disease detected. INTERPRETATION: Significant numbers of older Canadians have one or more major risk factors for cardiovascular disease. Many of these risk factors are amenable to modification. 相似文献
166.
167.
S. Ochieng K. Park T. Baker 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2002,188(4):325-333
Single-cell electrophysiological recordings were obtained from olfactory receptor neurons in antennal trichoid sensilla of male corn earworm, Helicoverpa zea. Spontaneous activity of the neuron specific for the major component ( Z)-11-hexadecenal, the conspecific female-emitted sex pheromone, was not affected by exposure to host plant volatiles. However, stimulations with binary mixtures of a threshold dosage of the pheromone component and increasing dosages of either linalool or ( Z)-3-hexenol significantly synergized the pheromone-specific neuron's firing rates compared with responses to the major pheromone component alone. Cross-adaptation studies confirmed that the enhanced impulses originated from the pheromone-component-tuned neuron. Because plant volatiles do not stimulate the pheromone-specific neuron when presented alone, the pheromone plus host odor blend would be interpreted as containing more pheromone than it actually does when processed by the pheromone-processing portion of the antennal lobe. 相似文献
168.
169.
目的比较两种肠内容物前处理和两种提取方法对清洁级SD大鼠肠内容物细菌基因组DNA提取效率。方法分别选用PBS多次离心漂洗、液氮破细胞两种前处理方法和酚/氯仿抽提、试剂盒过柱法两种提取方法进行组合分析,对4份肠内容物和16份含金黄色葡萄球菌肠内容物进行随机提取。结果大鼠肠内容物细菌基因组DNA含量和纯度测定结果显示,与PBS反复离心相比,液氮研磨前处理能显著提高大鼠肠内容物基因组DNA。荧光定量PCR表明,液氮研磨前处理较PBS反复离心能更好地收集细菌基因组DNA,其Ct值最低。结论研究结果表明,采用液氮研磨试剂盒法在大鼠肠内容物DNA提取中是较为优良的方法,该方法为建立实验动物中微生物的定量PCR检测方法打下了基础。 相似文献
170.
利用高量测序方法探究生防细菌对丹参植株根际和根表土壤真菌群落多样性的影响。
向丹参植株根部施入生防细菌DS-R5,培养45 d后采集根际和根表土壤样品提取总DNA,扩增样品基因组DNA的V4―V5区后进行双端测序,利用生物信息学解析生防细菌对丹参植株根际和根表土壤真菌群落多样性的影响。
菌株DS-R5处理后增加了根际和根表土壤真菌群落的多样性和丰度;根际土壤共有物种种类大于根表土壤,说明菌株DS-R5处理后根际土壤处理与对照物种种类更接近,而对根表土壤中的微生物物种影响较大。真菌群落结构组成分析结果表明,不同土壤样品在门水平上共有优势真菌主要有子囊菌门、接合菌门、担子菌门和未分类;相比根表土壤对照样品,根表土壤处理样品中子囊菌门丰度下降了13.0%,接合菌门丰度升高了69.2%;根际土壤处理样品相比根际土壤对照样品,子囊菌门和接合菌门丰度分别升高了5.9%和8.9%,但二者差异无统计学意义。在属水平上,根表土壤样品经菌株DS-R5处理后提高了有益菌属的丰度,同时降低了有害菌属的丰度。
丹参植株施入生防细菌后,改变了根际土壤和根表土壤中微生物群落结构和多样性,本研究结果可以为利用生防细菌防控丹参根腐病提供理论参考。