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161.
粤北蚁狮生态学的初步研究 总被引:2,自引:1,他引:2
根据多年来对粤北蚁狮的调查和试验,研究了粤北自然界穴蚁蛉的生活史,蚁狮4种生境类型,5目数十种昆虫食物分布和坐等式的捕食方式.结果表明,在一定范围内,饲食量一定时,饲食频率增大1倍,蚁狮个体发育历期缩短20%,35天内幼虫结茧化蛹率提高41.75%. 相似文献
162.
Moritoshi Iwagami Noppadon Tangpukdee Polrat Wilairatana Srivicha Krudsood Le Duc Dao Shusuke Nakazawa Muth Sinuon Duong Socheat Junko Yasuoka Masamine Jimba Hisami Watanabe Jun Kobayashi Hiromu Toma Viengxay Vanisaveth Bouasy Hongvanthong Paul T. Brey Shigeyuki Kano 《Parasitology international》2018,67(6):816-823
Malaria morbidity and mortality have decreased gradually in the Greater Mekong Subregion (GMS). Presently, WHO sets a goal to eliminate malaria by 2030 in the GMS. However, drug-resistant malaria has been reported from several endemic areas. To achieve the goal of elimination, the status of the emergence and spread of drug resistance should be monitored. In this study, the genotype of the Plasmodium falciparum chloroquine (CQ) resistance transporter gene (pfcrt) and 6 microsatellite DNA loci flanking the gene were examined. P. falciparum isolates (n?=?136) was collected from malaria patients in Thailand (n?=?50, 2002–2005), Vietnam (n?=?39, 2004), Laos (n?=?15, 2007) and Cambodia (n?=?32, 2009). Amino acid sequences at codons 72–76 on the gene were determined. All of the isolates from Thailand were CQ-resistant (CVIET), as were all of the isolates from Cambodia (CVIET, CVIDT). Thirteen of the 15 isolates (87%) from Laos were CQ-resistant (CVIET, CVIDT), whereas the other 2 (13%) were CQ-susceptible (CVMNK). In contrast, 27 of the 39 isolates (69%) from Vietnam were CQ-susceptible (CVMNK), whereas the other 12 (31%) were CQ-resistant (CVIET, CVIDT, CVMDT) or mixed (CVMNK/CVIDT). The mean of expected heterozygosity of the microsatellite loci was 0.444 in the Thai population, 0.482 in the Cambodian population, and 0.734 in the Vietnamese population. Genetic diversity in the Thai population was significantly lower than that in the Vietnamese population. These results suggested that chloroquine selective pressure on P. falciparum populations is heterogeneous in the GMS. Therefore, further examination to understand the mechanisms behind the emergence and spread of drug-resistant malaria are needed. 相似文献
163.
转基因作物的产业化作为当前生命伦理学的重要问题之一日益受到我国学术界、政府和广大公众的关注。转基因作物产业化不仅关涉到我国13亿人的吃饭问题,也与我国公众的身心健康、基本权利密切相关。转基因作物产业化的生命伦理意蕴主要体现在:转基因作物产业化的基础是确保公众健康与生命安全,关键是尊重公众权利,核心是促进社会公正。 相似文献
164.
Herbaceous model species, especially Arabidopsis has provided a wealth of information about the genes involved in floral induction and development of inflorescences and flowers. While the genus Populus is an important model system for the molecular biology of woody plant. These two genuses differ in many ways. This study was designed to improve understanding of flower development in poplar at a system level, as its regulatory pathway to a large extent remains poorly known, owing to the presently limited mutant pool. To address this issue, a poplar GeneChip was employed to detect genes expressed during the whole floral developmental process. Using the expressed floral genes, a systematic gene network was constructed with the aid of functional association with Arabidopsis. The results suggested that autonomous, gibberellin, vernalization, photoperiod, ethylene, brassinosteroid, stress-induced and floral suppression pathways are involved in poplar flowering. Modularity analysis revealed several pathways in common with Arabidopsis, such as autonomous, gibberellin, vernalization and photoperiod pathways. In addition, brassinosteroid, stress-induced and floral suppression pathways were implicated as additional novel pathways. Notably, a difference in vernalization between Arabidopsis and poplar was revealed. Autonomous, gibberellin, vernalization, photoperiod, ethylene, brassinosteroid, stress-induced and floral suppression pathways integrated into a systematic gene network in floral development of poplar. Compared to Arabidopsis, brassinosteroid, stress-induced and floral suppression pathways are additional in poplar, and FLC is absent in vernalization pathway in poplar. Preliminary conclusions drawn here provide a basis for both identification of key genes and elucidation of molecular mechanisms involved in poplar floral development. 相似文献
165.
目的分析大连市2011-2017年7例输入性卵形疟原虫感染病例的病原、抗原及核酸检测结果,以提高卵形疟原虫诊断的准确率和效率。方法收集7例疑似疟疾患者的血样,对血样进行血涂片镜检、快速疟疾诊断试纸条检测(RDT)及荧光定量PCR检测。结果血涂片镜检结果显示7例患者均感染卵形疟原虫。RDT检测结果显示2例阴性,另外5例为泛疟原虫抗原阳性。荧光定量PCR结果显示7例患者均检出疟原虫属和卵形疟原虫核酸。结论综合镜检、RDT及荧光定量PCR检测结果确定该7例患者均为卵形疟原虫感染。 相似文献
166.
半干旱区采煤沉陷对地表植被组成及多样性的影响 总被引:7,自引:0,他引:7
对神府-东胜矿区6个矿3种不同地貌下2个不同沉陷年份及对照区地表植被进行了调查,计算并分析了各样地植物种的重要值、物种多样性指数和均匀度等.结果表明:(1)神府-东胜矿区植物种类总体上来看较为稀少,生态较为脆弱;在调查区内共出现植物30科 82属 114种.(2)6个矿中以上湾、大柳塔和活鸡兔3矿区植物种类较丰富,补连塔和乌兰木伦矿区物种相对单一.(3)经沉陷干扰后,植物群落主要组成成分没有发生明显变化,群落的建群种没有改变;除生态十分脆弱的乌兰木伦矿区外,其余矿区地表沉陷后物种多样性与对照相比没有显著性差异;(4)沉陷后群落组成成分较沉陷前增多,且沉陷1年区比沉陷当年区物种数多,它们之间具有明显的相关性. 相似文献
167.
Larsen PD Zhong S Gebber GL Barman SM 《American journal of physiology. Regulatory, integrative and comparative physiology》2000,279(1):R210-R221
In urethan-anesthetized cats, frequency domain analysis was used to explore the mechanisms of differential responses of inferior cardiac (CN), vertebral (VN), and renal (RN) sympathetic nerves to electrical stimulation of a discrete region of the medullary raphe (0-2 mm caudal to the obex). Raphe stimulation in baroreceptor-denervated cats at frequencies (7-12 Hz) that entrained the 10-Hz rhythm in nerve activity decreased CN and RN activities but increased VN activity. The reductions in CN and RN discharges were associated with decreased low-frequency (=6 Hz) power and either increased (low stimulus intensity) or decreased (high stimulus intensity) 10-Hz band power. In contrast, VN 10-Hz band power was increased at all stimulus intensities, without changes in low-frequency power. High-frequency (25 Hz) stimulation decreased low-frequency activity of CN and RN discharges in both baroreceptor-denervated and baroreceptor-intact cats, without decreasing VN low-frequency activity. We propose that the differential pattern produced by raphe stimulation involves resonance at the level of the 10-Hz oscillators and differential inhibition of follower circuits that transmit both 10-Hz and low-frequency activity to sympathetic nerves. 相似文献
168.
169.
Comprehensive analysis of NAC family genes in Oryza sativa and Arabidopsis thaliana. 总被引:5,自引:0,他引:5
170.
甲氰菊酯和辛硫磷及其混剂的土壤微生物降解 总被引:7,自引:3,他引:7
The degradation rates of fenpropathrin, phoxim and their mixture in un-sterilized soil were much quicker-than those in sterilized soil, which indicated that soil microorganisms played a significant role in the degradation pro-cessin soil. The half-life (T0.5) in un-sterilized soil was 56.2 d for fenpropathrin, 57.8 d for mixed fen-propathrin, 48.2 d for phoxim, and 41.7 d for mixed phoxim. The corresponding half-life (T0.5) in sterilizedsoil was 135.1 d, 147.3 d, 123.6 d, and 126.2 d, respectively. There were no significant differences for degradation rates between single use and mixed use of fenpropathrin and nhoxirn. 相似文献