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991.
BackgroundTo investigate the association between single nucleotide polymorphisms (rs10078761, rs12696304, rs2853669, rs16847897, rs2736100, rs10069690) of telomerase gene (TERT) and the risk clinical benign prostatic hyperplasia (BPH) in a Chinese Han population of the Northwest region.MethodsA total of 150 BPH patients and 150 healthy older males from the northwest Chinese Han population were included in this study. The sample size for this unmatched case-control study was estimated by the look-up table method. Meanwhile, the general information and disease data of patients were collected. Age was only collected in healthy control subjects for statistical correction. Genotypes were detected using a multiplex PCR + ligase detection reaction (LDR). Typing results and clinical data were statistically analyzed using multiple linear regression and logistic regression. Pearson correlation was used for Hardy-Weinberg equilibrium.ResultsThe included population is in Hardy-Weinberg equilibrium. There was no significant association between SNP and the risk of BPH by correlation analysis. However, 4 haplotypes (TCTGGT, TCTGTC, TGCCTC, and TGTGTC) were identified as risk factors of BPH by haplotype analysis. The SNP rs2853669 is an independent risk factor for smooth muscle type of hyperplasia. Besides, rs2736100, rs10078761, and rs10069690 which are in linkage disequilibrium are associated with the severity of BPH.ConclusionsPolymorphism of the TERT gene determines the different disease development and pathological manifestations of BPH in the Chinese Han population the Northwest region.  相似文献   
992.
BackgroundThe effect of caudal block (CB) on the incidence of urethroplasty complications in hypospadias repair remains controversial. The evidence is conflicting, and some confounding bias issues need to be addressed. We sought to study a more homogenous group of distal hypospadias patients undergoing primary tubularized incised plate (TIP) repair by a senior pediatric urology surgeon in the past 2 years to examine the relationship between urethroplasty complications and the use of CB.MethodsWe reviewed our database to identify consecutive patients who had undergone hypospadias repairs by a senior director surgeon at our Center between January 2018 and November 2020. To be eligible to participate in the study, patients had to meet the following inclusion criteria: (I) have distal hypospadias; (II) have undergone a primary TIP repair; and (III) have attended follow-up appointments for a minimum period of 6 months. The primary outcome was the development of urethroplasty complications during the follow-up period. The principal variable of interest was whether or not CB was used perioperatively. The patients were categorized into a CB group (general anesthesia combined with CB) or a control group (general anesthesia only). Other potential risk factors were analyzed, including patient age at operation, patient weight, glans width, and the length of the urethral plate defect.ResultsThirty (12.2%) of the distal patients developed postoperative surgical complications. The postoperative surgical complication rates were similar between the different anesthesia groups. Weight, the length of the urethral plate length, and glans width did not contribute to the risk. Age was the only independent risk factor for postoperative surgical complications, and the complication rates increased in older patients.ConclusionsOur data from consecutive TIP repairs in distal hypospadias patients indicated no association between the use of CB anesthesia and the postoperative urethroplasty complication rate. Patients who were older in age when they underwent surgery had a higher risk of complications.  相似文献   
993.

Although the carbendazim is widely used to manage spot blight in celery cultivation, information on residues identified is of interest. In this study, we examined the dissipation and residual amounts of carbendazim in celery and soil under different cultivation methods when using the suggested dose and ten times of that and the bioconcentration factor of carbendazim for celery. The results showed that when celery leaves were sprayed with the suggested dose, the half-lives in a celery field and greenhouse were 2.75 days and 3.29 days, respectively. When the soil matrix was sprayed with the recommended dose before cultivation, the half-lives of carbendazim residues were 16.86 days and 11.97 days. We also conducted a long-term dietary risk assessment using the corresponding criteria. The results showed that, in China, the use of carbendazim at a dose of 0.022 g/m2 is safer and more reasonable when the harvest interval is 28 days.

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994.
目的 分析我国麻疹病例时空分布和空间聚集性特征。方法 资料来源于中国疾病预防控制信息系统传染病疫情报告监测系统2001-2016年全国麻疹病例数据,人口学数据来源于国家统计局。运用ArcGIS 10.2软件进行全局和局部空间自相关分析,运用SaTScan 9.6软件进行时空扫描分析。结果 2001-2016年全国共报告麻疹1 012 537例,年发病率整体呈下降趋势。2001-2004、2005-2008和2009-2012年的麻疹发病存在全局空间聚集性,其Moran''s I值分别为0.29、0.26和0.31。局部空间自相关分析结果显示,麻疹在各时间阶段均存在高-高聚集区域并主要集中在西部地区,同时2005-2008年广东省是一个单独的高-低离散区域,未检测到低-低聚集区域。时空扫描结果显示,2001-2008年我国麻疹病例在西部地区、华中地区和华北地区、山西省和广西壮族自治区形成一个广泛的聚集区。结论 2001-2016年我国麻疹的发病在空间、时间上均存在一定的聚集性,可根据聚集情况,为麻疹防控策略的制定提供依据。  相似文献   
995.
目的探讨我国长寿地区65岁及以上老年人氧化应激水平与高甘油三酯血症的关系。方法研究对象来源于2017-2018年“老年健康生物标志物队列研究”,最终将我国9个长寿地区2393名65岁及以上老年人群纳入研究。通过问卷调查和体格检测,收集调查对象的人口学特征、生活方式及健康状况等信息,同时采集调查对象的静脉血以检测丙二醛(MDA)、超氧化物歧化酶(SOD)及甘油三酯水平。采用限制性立方样条拟合多重线性回归模型分析MDA、SOD与甘油三酯的关联,采用广义线性混合效应模型分析氧化应激与高甘油三酯血症的关联。结果2393例调查对象年龄为(84.6±11.3)岁,最小65岁,最大112岁;男性1145名(47.9%);甘油三酯水平为(1.4±0.8)mmol/L,高甘油三酯血症检出率为9.99%(239名)。限制性立方样条拟合多重线性回归模型分析结果显示,MDA水平与甘油三酯水平呈线性关联;SOD水平与与甘油三酯水平呈非线性关联。广义线性混合效应模型分析结果显示,调整相关混杂因素后,MDA每升高1 nmol/ml,高甘油三酯血症检出风险增加[OR(95%CI)值为1.063(1.046,1.081)];SOD每升高1 U/ml,高甘油三酯血症检出风险降低[OR(95%CI)值分别为0.986(0.983,0.989)]。结论我国9个长寿地区65岁及以上老年人MDA和SOD水平与高甘油三酯血症发生风险有关联。  相似文献   
996.
目的 分析社区成年人高尿酸血症(HUA)与慢性肾病(CKD)发病风险的关系。方法 基于华东区域自然人群队列,对7 276例基线时未患CKD的上海市松江区20~74岁常住居民进行基于社区的前瞻性队列研究。CKD的诊断根据美国肾脏基金会慢性肾脏病实践指南的标准,HUA定义为血清尿酸(SUA)>420 μmol/L(男性)或>360 μmol/L(女性)。采用Cox比例风险模型分析HUA与CKD发病风险的关联。结果 经过中位时间2.65年的随访,队列人群新发CKD病例301例,累积发病率为4.14%,发病密度为16.01/1 000人年(95% CI:14.20~17.82)。CKD发病人群HUA的基线患病率显著高于非CKD发病人群。多因素Cox回归分析显示,HUA与CKD发病风险呈显著正关联,HUA患者的CKD发病风险HR值为1.92(95% CI:1.46~2.53)。在对性别、年龄、BMI、2型糖尿病、高血压等因素分层后,HUA与CKD发病风险仍呈显著正关联;在相加模型中,年龄与HUA存在交互作用,交互作用指数为1.78(95% CI:1.18~2.68)。结论 上海市松江区成年人CKD的发病率较高,HUA为CKD发病的独立危险因素。  相似文献   
997.
目的 数据缺失是队列研究中几乎无法避免的问题。本文旨在通过模拟研究,比较当前常见的8种缺失数据处理方法在纵向缺失数据中的填补效果,为纵向缺失数据的处理提供有价值的参考。方法 模拟研究基于R语言编程实现,通过Monte Carlo方法产生纵向缺失数据,通过比较不同填补方法的平均绝对偏差、平均相对偏差和回归分析的Ⅰ类错误,评价不同填补方法对于纵向缺失数据的填补效果及对后续多因素分析的影响。结果 均值填补、k近邻填补(KNN)、回归填补和随机森林的填补效果接近,且表现稳定;多重插补和热卡填充次于以上填补方法;K均值聚类和EM算法填补效果最差,表现也最不稳定。均值填补、EM算法、随机森林、KNN和回归填补可较好地控制Ⅰ类错误,多重插补、热卡填充和K均值聚类不能有效控制Ⅰ类错误。结论 对于纵向缺失数据,在随机缺失机制下,均值填补、KNN、回归填补和随机森林均可作为较好的填补方法,当缺失比例不太大时,多重插补和热卡填充也表现较好,不推荐K均值聚类和EM算法。  相似文献   
998.
发热伴血小板减少综合征流行病学研究进展   总被引:2,自引:0,他引:2       下载免费PDF全文
发热伴血小板减少综合征(SFTS)是21世纪初发现的一种新发蜱媒传染病。SFTS已在亚洲地区多个国家流行,包括中国、日本、韩国、越南、缅甸。截至2019年,我国已有25个省份报告SFTS病例,主要分布在山区和丘陵地带的农村,病例高度散发,但在地域分布上又相对集中,以河南、山东、安徽、湖北、辽宁、浙江和江苏7个省份为主。病例主要通过被携带病毒的蜱叮咬而感染,也可通过密切接触病例血液或体液感染。主要临床表现包括发热、胃肠道症状、血小板减少和白细胞减少,重症病例常因多器官功能衰竭而死亡。近年来,我国SFTS报告病例逐年上升,病死率始终维持较高水平,严重威胁人民身体健康。本文主要从SFTS的流行特征、传播流行的危险因素、临床特征等方面加以综述,旨在提升对SFTS疾病自然史的认知,加强传染病预防控制能力,降低疾病病死率。  相似文献   
999.
BackgroundHuman papillomavirus (HPV) vaccine has been increasingly discussed in mainland China since its first approval in 2016. To date, nearly all studies assessing HPV vaccine perceptions and attitudes were implemented during pre-licensure period. Therefore, the nationwide post-marketing survey was conducted to update knowledge, attitudes and practice on HPV vaccine among general population in mainland China.MethodsParticipants aged 18–45 years living in mainland China were recruited in April 2019 by multi-stage non-randomized sampling. Sociodemographic factors, HPV and HPV vaccine related awareness, knowledge, attitudes, vaccine uptake and potential obstacles were assessed in questionnaires. Bivariate analysis and multivariate regression were used to identify disparity among subgroups with different sociodemographic characteristics.Results4,000 women (32.1 ± 7.81y) and 1,000 men (31.8 ± 7.96y) were included in final analysis. Less than one third of participants had heard of HPV (female: 31%; male: 22%) and HPV vaccine (female: 34%; male: 23%). Knowledge score was also unfavorable on HPV (female: 3 out of 13; male: 1.8 out of 13) and HPV vaccine (female: 3 out of 6; male: 2 out of 5). Only 3% females had been vaccinated three years after HPV licensure in China, although willingness to get vaccinated among those unvaccinated were high (mean willingness score ± SD: female: 3.3 ± 0.97; male: 3.0 ± 0.98). Industry of employment and household income were the major factors related to awareness and knowledge of vaccine, whereas HPV and HPV vaccine awareness were key influential factors for willingness. The main obstacles of vaccination were safety concerns, lack of knowledge, and high price of HPV vaccines.ConclusionsFindings highlight a lack of vaccine awareness, knowledge, and poor uptake in mainland China and underscore the necessity of health education campaigns. The identified priority groups, contents to be delivered and practical obstacles could furthermore provide insight into health education to reduce disparities and accelerate HPV vaccine roll-out in China.  相似文献   
1000.
目的了解学龄儿童青少年的骨折发生特点及影响因素。方法选取参加“儿童青少年心血管与骨健康促进项目”2017年基线调查和2019年队列随访中骨折调查资料完整的12056名(男童49.4%)学龄儿童青少年作为研究对象。采用logistic回归分析年龄分组、BMI分组、骨折史及生活行为方式等因素与骨折发生风险的关系。结果北京地区学龄儿童青少年骨折的2年累计发生率为3.1%(95%CI:2.8%~3.4%),其中男童(4.1%)明显高于女童(2.1%),P<0.01;且在男童中呈现随年龄递增而在女童中递减的特点。骨折的发生部位以上肢为主(69.0%),不同性别年龄组间差异无统计学意义。此外,在男女童中均发现,骨折史是未来骨折发生的重要危险因素(男童:RR=1.81,95%CI:1.18~2.64;女童:RR=3.11,95%CI:1.74~5.13)。另在男童中发现,较长时间与频率的中高强度身体活动(≥120 min/d)和频繁饮用含糖饮料(≥1次/周)也可增加其未来骨折发生风险。结论北京地区学龄儿童青少年骨折率受到性别、年龄、骨折史和生活行为习惯的影响。应面向不同个体开展相应的预防策略,以避免儿童骨折的发生。  相似文献   
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