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991.
无脊椎动物乙酰胆碱酯酶研究进展   总被引:1,自引:0,他引:1  
乙酰胆碱酯酶(AChE)是生物体中一种十分重要的神经递质水解酶,也是有机磷和氨基甲酸酯类杀虫剂的作用靶标。AChE在不同生物中的性质显著不同,如编码基因个数、序列保守性、表达分布及生理功能等。作为杀虫剂的主要作用靶标之一,AChE不但可以通过单个点突变引起昆虫抗药性,还能够通过多个点突变联合作用、靶标表达量变化及基因复制等方式引起抗药性并且改变昆虫的适合度代价。本文主要从AChE的基因类型、分子进化、蛋白结构、生理功能、与昆虫的抗药性关系、同一物种中不同AChE的性质等6个方面对昆虫纲、蛛形纲和线虫等无脊椎动物AChE的研究进展作一综述。  相似文献   
992.
本研究的目的是以性腺完整的动物为模型调查左乙拉西坦(LEV)是否对于骨矿物质密度、骨结构和骨代谢生化指标产生影响,探究抗癫痫药物左乙拉西坦(LEV)是否对骨骼健康存在显著风险。本研究将实验大鼠分为对照组和试验组,每组10只。对照大鼠接受标准实验室饮食(SLD),而试验组中的大鼠喂食富含LEV的实验室饮食12周,并以双能X-线吸收仪测量全身、股骨和腰椎的骨密度。在骨组织中检查骨标记的浓度,股骨和胫骨均用于生物力学测试。研究结果表明:在LEV组中,脂肪组织的绝对值和相对值显著降低,全身骨密度增高,骨碱性磷酸酶(BALP)、Ⅰ型胶原C末端肽(CTX-1)和Ⅰ型前胶原氨基端前肽(PINP)浓度显著增加。本研究初步得出结论:在性腺完整的大鼠模型中长期施用LEV对骨质不具有负面影响。骨矿物质密度(BMD)的显著增加可能表明LEV对骨质可能有正面影响。  相似文献   
993.
为了揭示干扰素刺激基因(interferon-stimulated gene, ISG)表达的改变对乙型肝炎病毒感染治疗效果的影响,本研究检测了干扰素刺激基因STAT1、MX和SOCS3在慢性乙型肝炎患者的外周血单核细胞(peripheral blood mononuclear cell, PBMC)和肝脏样品中的表达情况。结果显示,采用聚乙二醇干扰素(Peg-IFN)治疗后,Peg-IFN应答者的PBMC和肝组织中的STAT1和MX表达水平显著升高,而非应答者的SOCS3表达显著升高。在应答者的活组织检查中,Peg-IFN治疗24 h后细胞核中磷酸化STAT1的染色比例显著增加,而非应答者在治疗前肝细胞核染色比例较高,治疗后染色比例显著减少。此外,治疗前非应答者的肝SOCS3表达水平显著高于应答者,并且随着IFN的治疗SOCS3表达继续增加。本研究表明,STAT1和MX是Peg-IFN抗病毒免疫应答的正向调节因子,而SOCS3 (JAK/STAT途径的负调节因子)激活干扰素刺激基因的负调控,并抑制Peg-IFN的免疫应答。  相似文献   
994.
为探讨个性化延续护理对2型糖尿病合并高血压患者生活质量及服药依从性影响,本研究选取2015年6月至2017年1月在哈励逊国际和平医院治疗的150例2型糖尿病合并高血压患者,随机分组,对照组患者应用常规护理,试验组患者给予个性化延续护理,观察比较两组患者血糖、血压、焦虑自评量表(self-rating anxiety scale, SAS)、抑郁自评量表(self-rating depression scale, SDS)、自尊量表(self-esteem scale,SES)、依从性差异。结果显示,12个月后试验组患者空腹血糖(7.59±1.26) mmol/L,糖化血红蛋白(glycated hemoglobin, HbAIC)(5.62±1.28)%较对照组明显下降(p<0.05);12个月后试验组患者收缩压(116.08±9.41) mmHg、舒张压(90.35±6.92) mmHg明显低于对照组(p<0.05);试验组患者SAS (35.13±4.27)分、SDS (31.42±2.09)分、SES (25.01±5.85)分同对照组比较明显改善(p<0.05);试验组患者依从性97.33%、不良生活习惯改善94.67%、健康知识掌握98.67%同对照组比较显著升高(p<0.05)。本研究结论初步表明针对2型糖尿病合并高血压患者应用个性化延续护理可改善患者血糖和血压水平,提高患者生活质量和治疗依从性,值得推广应用。  相似文献   
995.
非编码RNA不翻译成蛋白质,它们通过转录、转录后及翻译水平调控靶基因表达,在植物生长发育及逆境胁迫中发挥功能。目前,大量种子萌发期特异表达的非编码RNA (Non-coding RNA)已被发现,高效提取种子低分子RNA是对其进行研究的关键。本研究将介绍一种改良SDS RNA提取方法,并与Trizol、CTAB法、RNA提取试剂盒进行比较。结果表明:这种方法可以高效提取用于Northern blotting、RT-PCR等分子生物学分析的十字花科植物种子低分子RNA。改良SDS RNA提取方法为种子非编码RNA研究、种子萌发生理及分子育种研究提供了帮助。  相似文献   
996.
997.
This report reveals the structure of a virus extracted from the Korean horn beetle Allomyrina dichotoma. The purified virus particle was 100% identical to Allomyrina virus lef‐8 sequence registered as KM_233709.1. The structure of this virus was confirmed to be closely related to that of the Nudiviridae family, and it was rod shaped and enveloped, and observed to be of approximately the mean length of a single viral nucleocapsid of 200–210 nm and mean diameter of 100–110 nm. These results provide an insight into the structural characteristics of the Nudiviridae family that can be used for nudiviral identification.  相似文献   
998.
The Mangalitza pig breed has suffered strong population reductions due to competition with more productive cosmopolitan breeds. In the current work, we aimed to investigate the effects of this sustained demographic recession on the genomic diversity of Mangalitza pigs. By using the Porcine Single Nucleotid Polymorphism BeadChip, we have characterized the genome-wide diversity of 350 individuals including 45 Red Mangalitza (number of samples; n=20 from Hungary and n=25 from Romania), 37 Blond Mangalitza, 26 Swallow-belly Mangalitza, 48 Blond Mangalitza × Duroc crossbreds, 5 Bazna swine, 143 pigs from the Hampshire, Duroc, Landrace, Large White and Pietrain breeds and 46 wild boars from Romania (n=18) and Hungary (n=28). Performance of a multidimensional scaling plot showed that Landrace, Large White and Pietrain pigs clustered independently from Mangalitza pigs and Romanian and Hungarian wild boars. The number and total length of ROH (runs of homozygosity), as well as FROH coefficients (proportion of the autosomal genome covered ROH) did not show major differences between Mangalitza pigs and other wild and domestic pig populations. However, Romanian and Hungarian Red Mangalitza pigs displayed an increased frequency of very long ROH (>30 Mb) when compared with other porcine breeds. These results indicate that Red Mangalitza pigs underwent recent and strong inbreeding probably as a consequence of severe reductions in census size.  相似文献   
999.
Multiple trait selection indexes in pig breeding programmes should take into account the population structure and time delay between parent selection and expressions of traits in all production levels next to the trait impacts on economic efficiency of production systems. Gene flow procedures could be used for the correct evaluation of maternal and direct traits of pig breeds involved in breeding or crossbreeding systems. Therefore, the aim of this study was to expand a previously developed bioeconomic model and computer program to calculate the marginal economic values by including a gene flow procedure to calculate the economic weights for maternal and direct traits in pig breeds. The new program was then applied to the three-way crossbreeding system of the Czech National Programme for Pig Breeding. Using this program, the marginal economic values of traits for dam breeds Czech Large White in the dam position and Czech Landrace in the sire position, and for the sire breed Pietrain were weighted by the number of discounted gene expressions of selected parents of each breed summarised within all links of the crossbreeding system during the 8-year investment period. Economic weights calculated in this way were compared with the approximate economic weights calculated previously without a gene flow procedure. Taking into account the time delay between parent selection and trait expression (using discounting with half-year discount rates of 2% or 5%) and including more than one generation of parent progeny had little impact on the relative economic importance of maternal and direct traits of breeds involved in the evaluated three-way crossbreeding system. These results indicated that this gene-flow method could be foregone when estimating the relative economic weights of traits in pig crossbreeding systems applying artificial insemination at all production levels.  相似文献   
1000.
The epiphytic lichen Lobaria pindarensis is a Himalayan endemic species with little information on distribution, genetic diversity and structural complexity. During an intensive survey in the Nepal Himalayas, we collected 1256 thallus fragments from 45 phorophyte species to study their distribution and population genetics along an elevational gradient. We quantified genetic diversity and population structure of each symbiont at 17 fungus specific and 9 alga specific microsatellite loci. The Bayesian clustering identified three and two distinct gene pools for mycobiont and photobiont. We found that genetic diversity, allelic richness and gene pool composition and distribution were significantly influenced by elevation. We discovered both clonally and sexually reproduced repeated genotypes of the symbionts.  相似文献   
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