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111.
目的对虎杖中1个新的R2R3-MYB转录因子基因PcMYB1进行转录活性鉴定和表达特性分析,并在转基因拟南芥中进行功能研究。方法利用酵母单杂交实验分析PcMYB1的转录活性;荧光定量PCR(RT-PCR)技术检测虎杖中PcMYB1的表达模式;利用Wiesner染色和溴乙酰法检测PcMYB1转基因拟南芥中的木质素含量;RT-PCR技术分析PcMYB1转基因拟南芥木质素合成相关基因的表达。结果酵母单杂实验结果表明,PcMYB1具有转录抑制活性;RT-PCR结果显示PcMYB1在虎杖根、茎、叶中均有表达,在叶中表达量最高,并且紫外照射处理可诱导叶片中PcMYB1的表达;与野生型拟南芥相比,转基因拟南芥的株高降低了24.07%,木质部的细胞染色程度浅,转基因拟南芥木质素含量降低了14.81%,参与木质素合成的AtC4H、AtC3H、AtF5H、AtCOMT、AtCAD基因表达下调。结论 PcMYB1具有转录抑制活性,对植物木质素合成具有负调控作用。  相似文献   
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鲍雨婷  王琴  陈金  魏力  郝雅楠 《天津护理》2020,28(6):648-652
目的: 应用文献计量学方法,分析国内外医用粘胶相关性皮肤损伤(Medical adhesive-related skin injuries,MARSI)文献的研究主题和热点。方法: 检索Cochrane Library、PubMed、EMbase、Web of science、sinoMed、CNKI、Wanfang、VIP等数据库MARSI相关文献,检索时限为建库至2019年5月。采用SPSS 22.0 软件进行文献计量分析,利用gCLUTO统计对国内外高频主题词进行聚类分析。结果: 共纳入论文103篇,其中外文文献占总文献量的27.18%,中文文献占总文献量的72.82%。聚类分析将国内外高频主题词聚为4大类,依次为皮肤损伤及损伤类型、相关危险因素、风险评估及风险管理、护理干预措施。结论: MARSI仍是国内外研究的热点,其发病机制研究仍处于探索阶段,目前尚缺乏有效的预防策略,研究领域较局限。在今后的研究中,应加强MARSI预防的研究、注重多学科合作。  相似文献   
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IntroductionThis study was designed to investigate yoga teachers' and yoga therapists’ perceptions of the ways yoga is applied to treat symptoms of psychological distress, and identify the defining features, main components, and mechanisms of change in therapeutic practice.MethodsA qualitative design was employed. Six yoga teachers who had specific training and experience in teaching therapeutic yoga or practicing ‘yoga therapy’ took part in one-to-one interviews during which they gave accounts of their experiences of helping people cope with psychological distress through yoga. Participants' interviews were transcribed verbatim and were analysed using an integrative inductive-deductive thematic analysis.ResultsFour key themes were identified in relation to the benefits of therapeutic yoga: Awareness, Choice, Relationships, and Tailoring.ConclusionsThe findings support previous research which suggests that individualised yoga therapy is a promising intervention, and may help to form a theoretical rationale for the future treatment of psychological distress with yoga.  相似文献   
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目的调查四川省基层医院专科护士使用和考核现状,对其使用和考核体系进行探索。方法于2017年9月7-15日,采用问卷调查法对四川省38所二级及三级乙等医疗单位专科护士的使用和发展现状进行调查。结果共有38所医院参与网络问卷调查,其中34.21%的医院未针对专科护士设置岗位,岗位职责不清晰。有73.68%的专科护士未进行资质再认证,60.53%的专科护士学成后未进行专科资质再考核。结论我国对专科护士能力的评价认证体系尚未形成统一标准,对专科护士的培养条件也未形成统一标准。护士岗位管理中设置专科护士岗位能促进专科护士的职业发展规划,有利于专科护士使用和考核。  相似文献   
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We consider the scenario where there is an exposure, multiple biologically defined sets of biomarkers, and an outcome. We propose a new two-step procedure that tests if any of the sets of biomarkers mediate the exposure/outcome relationship, while maintaining a prespecified familywise error rate. The first step of the proposed procedure is a screening step that removes all groups that are unlikely to be strongly associated with both the exposure and the outcome. The second step adapts recent advances in postselection inference to test if there are true mediators in each of the remaining candidate sets. We use simulation to show that this simple two-step procedure has higher statistical power to detect true mediating sets when compared with existing procedures. We then use our two-step procedure to identify a set of Lysine-related metabolites that potentially mediate the known relationship between increased body mass index and the increased risk of estrogen-receptor positive breast cancer in postmenopausal women.  相似文献   
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Media can be a powerful communication tool to promote breastfeeding programs, influence mother's breastfeeding behaviour, and generate support among stakeholders for breastfeeding. Yet, there is little information on how media coverage influences a country's breastfeeding enabling environment. This study addressed this gap by conducting a retrospective content analysis of documents published between January 1, 2017 and January 1, 2018 to analyse the media coverage related to breastfeeding in Mexico. Content analysis was based on the breastfeeding gear model and a strategic planning technique to identify strengths, weaknesses, opportunities, and threats for enabling the national breastfeeding environment. Media coverage of breastfeeding was more frequent in August (36% of all documents). The top three topics commonly covered by the media were advocacy events promoting breastfeeding, promotion campaigns, and changes in breastfeeding legislation and policy. In general, the media coverage focused on strengths of specific breastfeeding policies. There was limited news coverage of key factors that negatively influenced or threatened the breastfeeding environment. Findings support the need to design strategies to engage the media covering in more depth and breadth diverse aspects of breastfeeding protection, promotion, and support efforts in Mexico.  相似文献   
118.
Accurate modeling of intratumor heterogeneity presents a bottleneck against drug testing. Flexibility in a preclinical platform is also desirable to support assessment of different endpoints. We established the model system, OHC-NB1, from a bone marrow metastasis from a patient diagnosed with MYCN-amplified neuroblastoma and performed whole-exome sequencing on the source metastasis and the different models and passages during model development (monolayer cell line, 3D spheroid culture and subcutaneous xenograft tumors propagated in mice). OHC-NB1 harbors a MYCN amplification in double minutes, 1p deletion, 17q gain and diploid karyotype, which persisted in all models. A total of 80–540 single-nucleotide variants (SNVs) was detected in each sample, and comparisons between the source metastasis and models identified 34 of 80 somatic SNVs to be propagated in the models. Clonal reconstruction using the combined copy number and SNV data revealed marked clonal heterogeneity in the originating metastasis, with four clones being reflected in the model systems. The set of OHC-NB1 models represents 43% of somatic SNVs and 23% of the cellularity in the originating metastasis with varying clonal compositions, indicating that heterogeneity is partially preserved in our model system.  相似文献   
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