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微小RNA(miRNA)是一类非编码的小分子RNA,是基因表达的转录后调控因子。简述了多种慢性肝病,包括代谢功能障碍相关性脂肪性肝病、慢性乙型肝炎、慢性丙型肝炎、慢性药物性肝损伤、肝硬化以及肝细胞癌的相关病因,归纳了近年来关于miR-125b通过靶向不同的靶基因,进入不同的信号转导途径而在同一肝病或病理进程中发挥着相同或相悖的调控作用的相关报道,以期为多种慢性肝病的发病机制研究和非创伤性鉴别手段的建立提供相关见解。  相似文献   
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《Vaccine》2019,37(36):5270-5275
BackgroundA vaccine manufacturer in China and regulatory authorities have been the focus of widespread outrage due to a vaccine scandal. We conducted a rapid survey during a time of intense mainstream and social media attention to determine whether the public’s confidence in vaccines was affected.MethodsWe selected 7 cities that were not involved in the scandal as the setting for the survey, which was conducted in August 2018. We used a convenience sampling strategy to select subjects in urban streets and rural villages for a face-to-face questionnaire-based survey. Subjects were asked to describe their levels of confidence on a scale from 0 to 9, in which 0 means no confidence, and 9 means very confident. Respondents were asked to assess confidence for two points in time – recollection of their level of confidence before hearing about the scandal and their level of confidence at the time of the survey.ResultsIn total, 683 individuals were invited to participate and 591 questionnaires were completed, for a response rate of 86.5%. Among respondents, 86.80% had heard of the vaccine scandal. The most common channel for hearing about the scandal was social media (e.g., WeChat), 40.6% of respondents. Regardless of gender, age, education level, province, town or country, or having children under 15 years old, respondents reported a significant decrease in confidence in domestically-produced vaccines. The mean pre-scandal confidence level recalled by respondents was 6.7, and the mean confidence level at the time of the survey was 3.2. Confidence in vaccine manufacturers, institutes for drug control, and drug supervision authorities decreased from 5.6 to 6.0 before the vaccine scandal to 2.0–3.2 at the time of the survey. Confidence in vaccine manufacturers decreased the most, from 5.6 before the scandal to 2.0; confidence in institutes for drug control decreased from 5.8 before the scandal to 2.6 at the time of the survey.ConclusionThis study demonstrated that public confidence was significantly affected by the vaccine scandal, particularly for vaccine producers and drug regulators. The decline in confidence is a reminder to governments that in order to build public confidence for vaccination, regulators have to reform regulatory practices and manufacturers have to ensure vaccine quality.  相似文献   
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ObjectivesTo explore the provision of medical care at ‘unlicensed’, full-contact amateur and lower-level professional combat sports competitions in England.DesignQualitative, mixed methods.MethodsObservations totalling 200 h of fieldwork shadowing medical professionals at 27 individual combat sports events, alongside formal, semi-structured interviews with 25 medical professionals, 7 referees and 9 promoters/event staff.ResultsPractices and standards vary widely. Event organisers and promoters often have very little understanding of how different types of medical practitioners operate. They rarely, if ever, check that the staff they are hiring are qualified, sometimes resulting in unqualified staff being used to provide medical cover at events. Venues are often poorly equipped to accommodate basic medical procedures. Patient confidentiality is very often compromised. Medical professionals often have limited autonomy within the combat sports milieu and may find themselves marginalised, with their judgements overruled by non-medical staff during competitive events. Some practitioners are cognisant of the dangers such working environments pose to their professional reputations and livelihoods, but remain working within combat sports regardless.ConclusionsDespite pockets of good practice, the lack of standardised rules for medical care provision creates substantial risks to athletes, to practitioners and the standing of the profession. The development and implementation of standardised, enforceable regulatory frameworks for full-contact combat sports in England is urgently needed.  相似文献   
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目的 评估《广州市控制吸烟条例》(简称条例)实施效果.方法 采用分层多阶段整群抽样的方法建立研究队列,以面对面问卷调查的方式进行3次随访调查.采用x2检验比较条例实施前后调查对象的人口学特征、公共场所吸烟状况、烟草广告及促销活动和媒体宣传与大众反应等方面的情况.结果 能正确掌握公共场所禁烟规定的比例较低;公共场所劝阻吸烟的比例较小;烟草广告及推销活动和媒体中吸烟镜头出现的比例虽然有下降趋势但依然常见;媒体禁烟信息出现的比例有增加的趋势;大多数的调查对象认为各种形式控烟宣传有一定社会效应,希望在公共场所室内全面禁烟.结论 条例实施后控烟确有一定效果,但是条例修正后,控烟效果进一步的提升效果有限.  相似文献   
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The presence of pesticides in the Israeli food supply is well documented but little is known about the risks posed by children's diets for potential exposures. We investigated potential exposures to food-borne pesticides in a sample of 301 urban Israeli children (2008–10). Data from a food frequency questionnaire, 24 hour food recall, and Israel's national pesticide monitoring program were used to estimate uptake factors for 26 compounds in 27 fruits and vegetables. A pilot risk assessment was performed and the findings were compared with the Israel Ministry of Health's 2012 pesticide risk assessment for the general population. The surveyed children had higher potential exposures than the general population for over one third of the compounds, and uptake factors exceeded the Acceptable Daily Intake in ten compounds. Methamidophos, exceeded the ADI at the 25th percentile and fenamiphos, iprodione, and oxydemethon methyl, exceeded the ADI at the 50 percentile. ADIs for several compounds were exceeded even though the residues detected were below the statutory limit. Improved monitoring, enforcement, and revision of the Maximum Residue Limit for certain food/pesticide pairs are indicated as is the need to incorporate data on children's actual food consumption in national risk assessments.  相似文献   
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【目的】探讨食管癌组织中miR-133表达对其癌细胞生长的影响。【方法】采用RT-PCR法检测miR-133在食管癌组织中的表达。利用脂质体Lipofectamine 2000将miR-133 mimics、anti-miR-133及其分别相应的对照转入食管癌细胞中,RT-PCR检测miR-133的表达,MTT法检测细胞增殖能力,Western blot检测细胞中EGFR蛋白的表达。【结果】miR-133在食管癌组织中的相对表达量(0.33±0.08)显著低于其癌旁正常组织(1.15±0.18)。miR-133过表达显著抑制了食管癌细胞的生长,而miR-133的下调显著增强了肿瘤细胞的生长。同时,miR-133的过表达抑制了EGFR mRNA和蛋白的表达,miR-133的下调显著增强了EGFR mRNA和蛋白的表达。EGFR的过表达逆转了miR-133对食管癌细胞生长的抑制效应。【结论】miR-133通过调控EGFR的表达进而抑制食管癌细胞的生长。  相似文献   
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