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151.
新疆杏树吐伦球坚蚧的防治指标与田间药效试验   总被引:1,自引:0,他引:1  
通过对吐伦球坚蚧Rhodococcus turanicus Arch.种群密度与杏树产量的调查和田间药效试验研究得出:40%毒死蜱·机油乳剂对其防治效果较好,7d后的防治效果可达83.99%;初步探明了吐伦球坚蚧的为害损失率,建立了杏树损失率与吐伦球坚蚧种群密度的回归模型为y=24.671Ln (x)-16.56(y为...  相似文献   
152.
Objective:To investigate the expression of interleukin-17 (IL-17) in zoledronic acid combined with PVP technology for patients with postmenopausal osteoporotic vertebral compression fracture (OVCF) and its predictive value for relapse.Methods:101 OVCF patients treated in our hospital from April 2013 to January 2015 were collected as a research group and treated by zoledronic acid combined with PVP technology. 80 healthy people with physical examination were assigned to the control group. ELISA was used to detect the expression of IL-17 in serum of the two groups. Patients were followed up for 2 years. The expression of IL-17 before treatment was compared between patients with relapse and patients without relapse. The predictive value of IL-17 in relapse was drawn according to ROC curve.Results:Before treatment, the expression of IL-17 in the research group increased significantly (p<0.05). After treatment, the expression of IL-17 in the research group decreased significantly (p<0.05). The level of IL-17 in patients with relapse was significantly higher than that in patients without relapse (p<0.05).Conclusions:IL-17 is highly expressed in postmenopausal patients with osteoporotic vertebral compression fracture and is expected to be a potential predictor of relapse in postmenopausal patients with OVCF.  相似文献   
153.
154.
Research ethics regulation in parts of the Global North has sometimes been initiated in the face of biomedical scandal. More recently, developing and recently developed countries have had additional reasons to regulate, doing so to attract international clinical trials and American research funding, publish in international journals, or to respond to broader social changes. In Taiwan, biomedical research ethics policy based on ‘principlism’ and committee‐based review were imported from the United States. Professionalisation of research ethics displaced other longer‐standing ways of conceiving ethics connected with Taiwanese cultural traditions. Subsequently, the model and its discursive practices were extended to other disciplines. Regulation was also shaped by decolonizing discourses associated with asserting Indigenous peoples’ rights. Locating research ethics regulation within the language and practices of public policy formation and transfer as well as decolonization, allows analysis to move beyond the self‐referential and attend to the social, economic and political context within which regulation operates.  相似文献   
155.
采用田间试验方法,研究了4种施肥方式(CK、A1、A2、A3)对2个甜高粱品种‘新高粱3号’(XT-2)和‘新高粱9号’(T601)秸秆生物产量、糖分含量和蔗糖代谢相关酶活性的影响。结果表明:(1)施肥方式对2个品种的生育天数没有影响;品种XT-2以氮、磷、钾后移改进作追肥施入处理(A3)的生物产量最高(54 916.96kg/hm2),而T601以生育前期施入磷、钾肥全部作基肥一次施入处理(A1)的生物产量最高(64 136.60kg/hm2),两者分别比CK(不施肥)增产14.96%和10.48%。(2)甜高粱秸秆总糖含量与蔗糖含量随生育期变化趋势基本一致,秸秆总糖含量在拔节期很低,其基本从挑旗期开始积累,并于成熟期达到最高值,且以XT-2品种在A3处理下的总糖含量最高(达到鲜基重12.7%)。(3)施肥方式对甜高粱秸秆蔗糖磷酸合成酶合成酶(SPS)和蔗糖合成酶(SS)活性的影响很明显,并以品种T601在A3处理下的SS活性最高(266.74mg.g-1.h-1)、品种XT-2在A1处理下的SPS活性最高(431.21mg.g-1.h-1),且二者均与其他处理差异极显著。研究发现,适宜施肥方式能显著提高甜高粱秸秆的生物产量、糖分含量和蔗糖代谢相关酶(SS、SPS)活性,从而有效改善甜高粱品质,增加其产量。  相似文献   
156.

Background

The assessment of blood lipids is very frequent in clinical research as it is assumed to reflect the lipid composition of peripheral tissues. Even well accepted such relationships have never been clearly established. This is particularly true in ophthalmology where the use of blood lipids has become very common following recent data linking lipid intake to ocular health and disease. In the present study, we wanted to determine in humans whether a lipidomic approach based on red blood cells could reveal associations between circulating and tissue lipid profiles. To check if the analytical sensitivity may be of importance in such analyses, we have used a double approach for lipidomics.

Methodology and Principal Findings

Red blood cells, retinas and optic nerves were collected from 9 human donors. The lipidomic analyses on tissues consisted in gas chromatography and liquid chromatography coupled to an electrospray ionization source-mass spectrometer (LC-ESI-MS). Gas chromatography did not reveal any relevant association between circulating and ocular fatty acids except for arachidonic acid whose circulating amounts were positively associated with its levels in the retina and in the optic nerve. In contrast, several significant associations emerged from LC-ESI-MS analyses. Particularly, lipid entities in red blood cells were positively or negatively associated with representative pools of retinal docosahexaenoic acid (DHA), retinal very-long chain polyunsaturated fatty acids (VLC-PUFA) or optic nerve plasmalogens.

Conclusions and Significance

LC-ESI-MS is more appropriate than gas chromatography for lipidomics on red blood cells, and further extrapolation to ocular lipids. The several individual lipid species we have identified are good candidates to represent circulating biomarkers of ocular lipids. However, further investigation is needed before considering them as indexes of disease risk and before using them in clinical studies on optic nerve neuropathies or retinal diseases displaying photoreceptors degeneration.  相似文献   
157.
目的:分析囊型包虫病的CT以及超声的影像学特征以及联合诊断的效能,以减少对于CL及Ⅰ型包虫囊肿误诊率。方法:回顾性分析自2008年1月~2010年9月在我院行CT和超声检查的包虫病患者22例,肝脏单纯囊肿25例,分析其表现并进行比较。结果:CT检出36个病灶,超声检测出34个病灶,单纯囊肿组和包虫组病灶分布及形态等无明显差别,22例超声显示位于包虫囊肿底部可以随体位运动棘球呦砂样改变,显示囊肿壁不规则增厚3例,病灶周围胆管扩张2例,CT显示包虫囊肿壁钙化5例,病灶周围胆管扩张3例。结论:联合CT和超声学检查可以帮助提高CEI及CL型包虫囊肿的诊断率。  相似文献   
158.
以裂殖酵母NAC蛋白β亚基为对象在禾谷镰刀菌(Fusarium graminearum)基因组数据库中进行搜索,发现了同源蛋白基因FGSG 08675并命名为FgβNAC.通过基因敲除技术对禾谷镰刀菌FgNAC基因进行敲除和回补,分别获得了敲除菌株fgβnac和回补菌株fgβnac::FgβNAC,并分别对野生型菌株、敲除菌株和回补菌株进行了表型和致病性研究.结果表明,与野生型菌株PH-1相比,敲除菌株fgβnac在固体马铃薯培养基(PDA)上生长速率明显减慢,约为野生型菌株的一半,气生菌丝致密短小;同样在液体PD培养液中培养3d的敲除突变株的菌丝干重仅为野生型的56%.另外,敲除突变株的分生孢子产量相比野生型菌株下降了78.5%.进一步采用麦穗离体接种法对其致病性进行了检测,发现FgβNAC基因的缺失引起致病力显著地下降,仅局限于接种部位及邻近的小颖,而无法侵入维管束组织引起穗枯症状.  相似文献   
159.
不同利用强度下绿洲农田土壤微量元素有效含量特征   总被引:13,自引:0,他引:13  
以地处极端干旱背景下的塔里木盆地南缘策勒绿洲为研究区,以绿洲化为视角,根据当地农民耕作习惯于2005年选择4块试验农田,分别代表当地典型的农田利用强度。基于单项指数(Ei)和综合指数(Ec)相结合的评价方法,分析了绿洲农田在不同利用强度下的土壤Fe、Cu、Mn、Zn等微量元素有效性,探讨了土壤微量元素与人为耕作管理措施之间的关系。结果表明:人为耕作管理强度会对土壤微量元素有效含量产生重要影响,绿洲不同位置农田因施肥强度和管理方式的差别,其土壤微量元素有效含量特征存在显著差异。绿洲内部农田土壤有效Fe、Cu、Mn、Zn含量显著高于绿洲边缘各样地,新垦农田土壤有效Fe、Cu、Zn含量均低于对照样地;绿洲内部农田土壤微量元素有效性最高,新垦农田最低;农田土壤微量元素有效性与土壤有机质存在显著的正相关关系。  相似文献   
160.
目的:观察国人胚胎三叉神经节细胞分化及发育过程。方法:取水囊引产18-36周国人胎儿三叉神经节,HE染色及透射电镜观察。结果:18-20周胎儿三叉神经节神经元排列紧密,胞质少,可见到数量不多的线粒体,且其内几乎看不到嵴,其它细胞器少。25周时,线粒体嵴变长,粗面内质网雏形出现,有纵形小管出现;27周时可观察到成熟的高尔基复合体,32周后,线粒体、粗面内质网等细胞器发育趋于成熟。到33周电镜下可见溶酶体;36周时细胞内各种细胞器结构和功能基本完善。结论:人胚胎三叉神经节细胞发育过程中随胎龄增加,其结构和功能逐步完善,32~36周(8~9月)是细胞的分化发育重要时期。  相似文献   
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