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1.
目的 利用筛选出十堰的天师栗中高多态性SSR位点评价天师栗种质资源的遗传多样性,结合有效药用成分含量,构建十堰地区天师栗核心种质库。方法 收集十堰地区114份天师栗种质资源,以七叶树基因组为参考,采用荧光毛细管电泳筛选出高多态性SSR位点,对天师栗种质资源进行遗传多样性分析。利用HPLC测定不同种质干燥娑罗子中七叶皂苷的含量。采用最小距离逐步聚类取样策略(LDSS),根据遗传多样性保留程度初步筛选出核心种质,并对该核心种质与原始种质的遗传多样性参数进行T检验,选择与原种质差异不显著的核心种质为最佳核心种质。结果 筛选出13对高多态性SSR分子标记,遗传多样性评价结果表明十堰地区天师栗种质资源遗传多样性较高,遗传分化较小,存在着较大的基因流,114份种质资源未分为不同的亚群,周家坝和辽叶居群间具有较近的遗传亲缘关系,且周家坝居群娑罗子中的七叶皂苷A及七叶皂苷B含量普遍较高。最终筛选出的核心种质共23份,占总种质资源的20.17%,其中周家坝12份样本、辽叶6份样本、普龄5份样本。结论 将SSR分子标记与主要有效药用成分结合,采用LDSS取样策略构建十堰地区天师栗种质资源核心种质库的方法具有可行性,能够有效的保存与管理天师栗种质资源,也为当地天师栗品种改良、新品种选育研究等提供了研究基础。  相似文献   
2.
BackgroundA venous leg ulcer is a chronic leg wound caused by poor venous blood circulation in the lower limbs. It is a recurring condition causing pain, malodour, reduced mobility, and depression. Randomised controlled trials evaluating treatments for venous leg ulcers provide important evidence to inform clinical decision-making. However, for findings to be useful, outcomes need to be clinically meaningful, consistently reported across trials, and fully reported. Research has identified the large number of outcomes reported in venous leg ulcer trials, impacting both synthesis of results, and clinical decision-making. To address this, a core outcome set will be developed. A core outcome set is an agreed standardised set of outcomes which should be, as a minimum, measured and reported in all trials which evaluate treatment effectiveness for a given indication. A core outcome set has the potential to reduce research waste, improve the utility of RCTs, reduce reporting bias, facilitate treatment comparisons across different sources of evidence and expedite the production of systematic reviews, meta-analyses and evidence-based clinical guidelines.AimThe aim of this project is to develop a core outcome set for research evaluating the effectiveness of interventions for treating venous leg ulceration.MethodsThrough a scoping review of the literature on venous leg ulceration, we will firstly identify a list of candidate outcome domains (broad categories in relation to what is being measured) from randomised controlled trials and qualitative research, and outcomes (specific methods in relation to what is being measured). In two further stages, we will use the resulting lists of outcome domains and outcomes to design two online surveys. A range of stakeholders will be invited to participate in the surveys and they will be asked to indicate which outcome domains and outcomes are most important and should be considered as core in future research reports.  相似文献   
3.
《Clinical neurophysiology》2019,130(9):1562-1569
ObjectiveConventional deep brain stimulation (DBS) systems with ring-shaped leads generate spherical electrical fields. In contrast, novel directional leads use segmented electrodes. Aim of this study was to quantify the impedance variations over time in subjects with the directional Cartesia-Boston® system.MethodsImpedance records, programming settings, and clinical data of 11 consecutive Parkinsonian patients implanted with DBS directional leads in two Italian centers (Udine and Vicenza) were retrospectively evaluated. Data were collected before starting stimulation (in the operating room and at days 5 and 40) and after switching stimulation on at the successive follow-up visits (1, 6 and 12 months).ResultsDirectional leads have significantly higher impedance than ring leads. Stimulated contacts had always lower impedance compared to non-stimulated contacts. Before DBS-on, all contacts had higher impedance in the operating room, with an initial decrease five days post-surgery and a subsequent increase at day 40, more evident for directional contacts. The impedance of directional leads increased post-implantation at 1 and 6 months with a plateau at 12 months.ConclusionsThere was a significant difference between the directional and ring leads at baseline (before activation of DBS) and during follow-up (chronic DBS).SignificanceOur study reveals new information about the impedance of segmented electrodes that is useful for patient management during the initial test period, as well as during long-term DBS follow-up.  相似文献   
4.
本着以课程为中心的原则,研究组在基础医学综合实验课程建设、运行方式、教学方法改革等方面积极探索;以联系疾病、联系应用为导向,广泛开展基于疾病动物模型制备及干预过程的实验教学;增加"创新性"实验项目,确保课程内容体现出前沿性和时代性;以生物医学前沿方法训练引领课程建设,着力培养学员的学习能力、实践能力和创新能力。此外,在优化以实践应用、创新性为导向的课程内容建设的基础上,打造虚拟仿真实验项目,尝试线上线下混合式教学,全方位提升学员的实践运用能力。  相似文献   
5.
The purpose of this study has been to explore young children's understandings and experiences of friendship as these manifested in children's behaviours, in a reception class setting. Drawing on an evolutionary, ecological framework, friendship is seen as not only the expression and further development of social understandings and cognitive advances; more than that, making and maintaining friends is seen as an evolutionary trait and a ‘drive’ to relate to similarly minded others. Through ‘niche picking’, children select the environments and opportunities that suit them in order to develop their dispositions and individual traits. The research employed a participatory design in order to capture the children's views and experiences. It took place in a reception class setting, where children's everyday experiences were observed and discussed with them. The study identified six themes of analysis and offered some suggestions about creating enabling educational environments that allow the ‘space’ for niche construction.  相似文献   
6.
医改尚未成功,路在何方?   总被引:3,自引:0,他引:3  
目前我国医疗制度改革尚未取得成功,这与计划经济向市场经济转轨这历史时期及卫生工作的特殊性有关,出现问题,甚至失误,在所难免。提出(1)医改的目的是确保全国人民健康,人人享有医疗保健。(2)把卫生系统推向市场,医疗机构商业化,不是医改的方向。(3)预防为主,健全预防医学制系。(4)国家增加投入。(5)制定公立及私立医院各项制度,保护医务人员的合法权益。(6)加强社区基层医疗机构的建设。  相似文献   
7.
中医药高等院校专业建设应随着社会的进步发展和社会的需求而不断拓宽、延伸其专业领域,本文从中医药高校的专业延伸的必要性、建设原则以及专业延伸的思路等三个方面对中医药高等院校的专业建设工作提出了几点思考。  相似文献   
8.
9.
中医儿科是河南省重点学科,加强学科管理,健全各项管理规章制度,科学合理设置儿科课程,实现理论与实践的结合,课堂与临床见习的结合;提高教师人文素质、教学水平,是保证儿科教学质量的关键.  相似文献   
10.
目的:观察核心结合因子a1(Cbfa1)对兔骨髓间充质干细胞(MSCs)向成骨细胞分化的诱导作用。方法:体外分离培养兔骨髓MSCs,用AdEasy1/Cbfa1。转染MSCs,在转染后3d,1、2、3和4周时,组织化学和免疫组化等方法检测成骨标志碱性磷酸酶和骨钙素的表达。结果:AdEasy1/Cbfa1转染后的兔骨髓MSCs表现出与成骨细胞相似的形态,并且表达碱性磷酸酶和骨钙素。结论:Cbfa1可诱导兔骨髓MSCs向成骨细胞分化。  相似文献   
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