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81.
新疆吉木萨尔县蝴蝶群落多样性   总被引:1,自引:0,他引:1  
蝴蝶作为指示生物, 被广泛地应用于生物多样性监测及环境质量评估。探究新疆吉木萨尔县蝴蝶群落多样性, 可为当地蝴蝶多样性的保护及环境监测提供基础数据。本研究采用样线法在新疆吉木萨尔县选取山前荒漠、农田、山地草原、山地森林、亚高山草甸5种不同的生境类型, 对蝴蝶种类和群落多样性进行调查。共记录蝴蝶4,401号, 隶属于7科26属38种。其中蛱蝶科有9属12种, 为优势科; 粉蝶科的个体数最多, 占比55.01%; 绢蝶科、凤蝶科和弄蝶科的种类数和个体数最少, 均为单科种, 是该地区的稀有类群。对不同生境蝴蝶群落多样性和相似度分析比较的结果显示: 5种生境中多样性指数从高到低依次为亚高山草甸、山地森林、山地草原、农田及山前荒漠, 其中山地森林和亚高山草甸的相似性系数较高, 达到0.77, 山前荒漠和山地草原的相似性系数最低, 为0.37。蝴蝶物种数及多样性指数随海拔的增加呈上升趋势。蝴蝶群落随月份发生变化, 蝴蝶种类和数量在5月发生、7月达到峰值。蝶类个体数在3年内呈下降趋势。研究结果表明, 蝴蝶物种的组成和多样性与生境类型具有密切联系, 保护生态环境, 维持该地区植物群落的多样性、降低人为干扰程度是保护蝶类多样性的关键。  相似文献   
82.
The present study includes design and synthesis of new molecular hybrids of 2-methylthiobenzimidazole linked to various anti-inflammatory pharmacophores through 2-aminothiazole linker, to investigate the effect of such molecular variation on cyclooxygenase (COX) and 15-lipoxygenase (15-LOX) enzymes inhibition as well as in vivo anti-inflammatory activity. The chemical structures of new hybrids were confirmed using different spectroscopic tools and elemental analyses. Benzimidazole-thiazole hybrids linked to acetyl moiety 13, phenyl thiosemicarbazone 14, 1,3-thiazolines 15a-c and 4-thiazolidinone 16 exhibited significant COX-2 inhibition (IC50 = 0.045–0.075 µM) with significant COX-2 selectivity indices (SI = 142–294). All hybrids revealed potent 15-LOX inhibitory activity (IC50 = 1.67–6.56 µM). Benzimidazole-thiazole hybrid 15b was the most potent dual COX-2 (IC50 = 0.045 µM, SI = 294) inhibitor approximate to celecoxib (COX-2; IC50 = 0.045 µM, SI = 327), with double inhibitory activity versus 15-LOX enzyme (IC50 = 1.67 µM) relative to quercetin (IC50 = 3.34 µM). Three hybrids (14, 15b & 16) were selected for in vivo screening using carrageenan-induced paw edema method. Benzimidazole-thiazole hybrid linked to 4-thiazolidinone 16 showed the maximum edema inhibition at both 3 h and 4 h intervals as well (~119% and 102% relative to indomethacin, respectively). The gastric ulcerogenic effect of benzimidazole-thiazole hybrid 16 was estimated compared with indomethacin showing superior gastrointestinal safety profile. In bases of molecular modeling; all new active hybrids were subjected to docking simulation into active sites of COX-2 and 15-LOX enzymes to study the binding mode of these novel potent dual COX-2/15-LOX inhibitors.  相似文献   
83.
Every host is colonized by a variety of microbes, some of which can protect their hosts from pathogen infection. However, pathogen presence naturally varies over time in nature, such as in the case of seasonal epidemics. We experimentally coevolved populations of Caenorhabditis elegans worm hosts with bacteria possessing protective traits (Enterococcus faecalis), in treatments varying the infection frequency with pathogenic Staphylococcus aureus every host generation, alternating host generations, every fifth host generation, or never. We additionally investigated the effect of initial pathogen presence at the formation of the defensive symbiosis. Our results show that enhanced microbe‐mediated protection evolved during host‐protective microbe coevolution when faced with rare infections by a pathogen. Initial pathogen presence had no effect on the evolutionary outcome of microbe‐mediated protection. We also found that protection was only effective at preventing mortality during the time of pathogen infection. Overall, our results suggest that resident microbes can be a form of transgenerational immunity against rare pathogen infection.  相似文献   
84.
为提高农作物重大病虫害发生信息自动化、智能化采集能力,全面提升监测预警水平,笔者基于大数据、人工智能和深度学习技术,研发了一款农作物病虫害移动智能采集设备——智宝,主要实现了3个方面的功能:一是病虫害发生信息自动采集上报.通过该产品进行人工拍照,可实现对田间农作物重大病虫害发生图像、发生位置、发生数量、微环境因子等数据的实时采集和上报.二是自动识别计数.基于植保大数据与人工智能技术,通过构建病虫害自动识别系统,可实现重大病虫害精准识别与分析,只要拍摄照片,即可快速、精确地识别病虫害种类,并自动计数、上报到指定的测报系统.三是自动分析判别分级.针对拍摄采集上报的重大病虫害发生信息,系统可在自动识别和计数的基础上,进一步对病虫害发生严重程度进行智能判别分级,甚至根据相关预测模型,对病虫害的发生趋势进行辅助分析预测,提出预测建议.通过2016—2019年组织多地植保机构进行试验改进,该技术产品日趋成熟,有望在未来的农作物病虫害发生信息采集和预测预报工作中推广使用.  相似文献   
85.
86.
姜广顺  李京芝 《兽类学报》2021,41(5):604-613
目前全球物种正以前所未有的速度灭绝,对野生动物栖息地开展有效的评估与科学的保护是阻止濒危物种走向灭绝,保持其可持续生存与发展的重要前提和手段。本文针对我国的食肉类、有蹄类、灵长类、小型兽类、海洋兽类5个类别的濒危兽类,综述了其栖息地评估与保护研究进展的现状和成果,对相关学术成果进行了归纳与分析,以期为栖息地的科学保护与管理梳理出系统、可供借鉴的研究方法和技术手段,并对其理论和技术的挑战进行了展望,提出了我国濒危兽类栖息地评估和保护研究应走向整体化、定量化、智能化,以及多学科交叉融合应用的“精准化”发展方向,为国家生态建设工程的有效实施提供重要技术支撑。  相似文献   
87.
This special issue contains papers presented at the 6th International Entomophagous Insects Conference. Entomophagous insects consume other insects. They are a fundamental component of ecosystems and are extensively used as biocontrol agents. The first article reviews the role of ladybirds in biological control and the second reviews the biological control of stink bugs. The following nine research articles cover the rearing, behavior, life history, and ecology of parasitoid and predator species.  相似文献   
88.
89.
v-Src oncogene causes cell transformation through its strong tyrosine kinase activity. We have revealed that v-Src-mediated cell transformation occurs at a low frequency and it is attributed to mitotic abnormalities-mediated chromosome instability. v-Src directly phosphorylates Tyr-15 of cyclin-dependent kinase 1 (CDK1), thereby causing mitotic slippage and reduction in Eg5 inhibitor cytotoxicity. However, it is not clear whether v-Src modifies cytotoxicities of the other anticancer drugs targeting cell division. In this study, we found that v-Src restores cancer cell viability reduced by various microtubule-targeting agents (MTAs), although v-Src does not alter cytotoxicity of DNA-damaging anticancer drugs. v-Src causes mitotic slippage of MTAs-treated cells, consequently generating proliferating tetraploid cells. We further demonstrate that v-Src also restores cell viability reduced by a polo-like kinase 1 (PLK1) inhibitor. Interestingly, treatment with Aurora kinase inhibitor strongly induces cell death when cells express v-Src. These results suggest that the v-Src modifies cytotoxicities of anticancer drugs targeting cell division. Highly activated Src-induced resistance to MTAs through mitotic slippage might have a risk to enhance the malignancy of cancer cells through the increase in chromosome instability upon chemotherapy using MTAs.  相似文献   
90.
BackgroundAlthough considered an unusual etiological agent, Cyberlindnera (Candida) fabianii has been related to septicemia in several reports in recent years. Its doubtful or uncertain identification when using tests such as CHROMagar Candida, API® Candida, API® ID32C or VITEK® MS, leads to an underestimation of the cases produced by this yeast.AimsTo report the first isolation of C. fabianii in Chile and its identification.MethodsThe sequencing of the internal transcribed spacer region (ITS) was performed. Antifungal susceptibility profiles were obtained by means of the broth microdilution technique.ResultsThe identification was only reached by sequencing the ITS regions, which shows the limited usefulness of the conventional techniques in the identification of some yeast species. A dendrogram shows the phylogenetic relationship of the isolated strain with some other yeast species.ConclusionIn the identification of fastidious microorganisms or microorganisms whose identification is not completely reliable when using classical or even advanced methodologies, such as mass spectrometry, sequencing techniques are essential.  相似文献   
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