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991.
Asia is ageing fast. To develop more effective health promotion initiatives among older adults, more knowledge of the environmental correlates of physical activity is needed. However, research in this age group is rare, and most existing studies have been conducted within Western contexts. The present study explores the interaction effects of objective neighbourhood environment and satisfaction with neighbourhood environment on leisure-time physical activity in older adults in Beijing, China. This study follows a cross-sectional design and involves older adults aged 65 years and over. The questionnaire was collected in 2018 and 2,061 older adults living in Yanshan, Beijing, China were included in the analysis. Linear regression was applied to examine the effects. The findings show that residents who live in places with higher levels of walkability, or those who are more satisfied with neighbourhood environment (either path/road/street condition or recreational resources) spent significantly longer participating in leisure-time physical activity. However, the objective neighbourhood accessibility of recreational resources was not a significant factor of physical activity. Satisfaction with neighbourhood recreational resources can significantly moderate the relationship between objective neighbourhood accessibility of recreational resources and leisure-time physical activity respectively. This is the first study conducted in China examining the relationships between objective neighbourhood environment, satisfaction with neighbourhood environment and leisure-time physical activity among older adults. This study may have implications for urban planning and service provision planning. The design of built environments that considers quality rather than only quantity can play a significant role in improving older adults' leisure-time physical activity.  相似文献   
992.
In the past 40 years, the prevalence of eating disorders (ED) in China has shown an increasing trend, leading to an urgent need to develop efficient treatment modes and methods. Since the beginning of the new century, the diagnosis, treatment, and research of ED in China have been under development. This article gives an introduction and commentary on the treatment modes, treatment methods and their applications in ED in China. There are two main treatment forms for ED until now, that is, inpatient treatment and outpatient treatment. Inpatient treatment is recommended as the first choice. Since 2008, clinical psychotherapies such as cognitive behavioral therapy (CBT), dialectical behavioral therapy (DBT), and family-based treatment (FBT), which are effective for pathological symptoms of ED, have been introduced into China and developed clinically. Group CBT and group DBT for patients with ED and group FBT for caregivers might be the most efficient psychotherapy in China nowadays. A multi-family FBT support group could be developed as the basic treatment of ED patients. Although these new types of psychotherapy have observed effectiveness in clinical application, the Randomized Controlled Trials (RCT) are rare and need to be developed.  相似文献   
993.
For massive survival data, we propose a subsampling algorithm to efficiently approximate the estimates of regression parameters in the additive hazards model. We establish consistency and asymptotic normality of the subsample‐based estimator given the full data. The optimal subsampling probabilities are obtained via minimizing asymptotic variance of the resulting estimator. The subsample‐based procedure can largely reduce the computational cost compared with the full data method. In numerical simulations, our method has low bias and satisfactory coverage probabilities. We provide an illustrative example on the survival analysis of patients with lymphoma cancer from the Surveillance, Epidemiology, and End Results Program.  相似文献   
994.
目的采用超高效液相色谱-串联质谱技术,建立消毒产品中8类13种抗生素的检测方法。方法样品经甲醇或乙腈提取后,经Waters HSS T3色谱柱(100 mm×2.1 mm,1.8μm)分离,三重四级杆串联质谱仪检测。结果13种选定的抗生素在4~100μg/L范围内线性关系良好,相关系数均大于0.991,检出限为2~25μg/kg。在3种不同剂型的消毒产品中,低、中、高3个浓度加标水平的回收率为71.2%~130.4%,相对标准偏差均小于11.3%,满足消毒产品中抗生素违法添加的检测要求。运用建立的方法,在一份膏霜剂型的消毒产品中检测出氧氟沙星,含量为21.1 mg/kg,其余样品中均未检出相关物质。结论该方法简单、可靠、重现性好,覆盖的抗生素种类多。  相似文献   
995.
目的 了解重庆市涪陵区2009—2019年15岁以下人群流感病原学的流行趋势及特征,为今后的流感防控工作提供科学依据。方法 分析2009—2019年涪陵区流感网络监测实验室获得的15 岁以下人群流感样病例(Influenza-like illness,ILI)监测结果。结果 女性ILI病毒分离阳性率(14.53%)和男性阳性率(13.74%)无统计学意义(〖XC小五号.EPSP〗=0.98,P>0.05);初中生阳性率最高(23.94%),其次是小学生(19.69%)、幼儿园儿童(17.10%),散居儿童最低(7.64%),差异有统计学意义(〖XC小五号.EPSP〗=238.82,P<0.05);各学龄段儿童之间流感病毒类型构成差异有统计学意义(〖XC小五号.EPSP〗=40.71,P<0.05);ILI病毒检测阳性率的季节规律呈单、双峰交替出现,2010 年、2014 年、2015 年流行高峰出现在夏季,其余年份流行高峰均在冬春季;主要病原学类型为季H3(36.63%)、B型Victoria系(28.60%)、新甲H1(27.98%)、B型Yamagata系(6.44%),流感病毒阳性率与ILI病例数变化趋势相关(rs=0.312,P<0.05); ILI发病后采样时间、采样后送检时间对标本阳性率有显著影响。结论 涪陵区15岁以下人群流感流行处于上升趋势,流行高峰时间处于动态变化,近年来主要在冬春季;初中生和小学生ILI病毒检测阳性率高于学龄前儿童,提示冬春季要加强中小学校学生流感防控工作。  相似文献   
996.
目的分析2010-2019年住院治疗的肝脓肿患者基本情况、住院费用及其结构变化和影响因素,评估肝脓肿直接经济负担,探寻有效减轻肝脓肿疾病经济负担的方法。方法回顾性收集中南大学湘雅医院2010年1月-2019年12月收治的495例肝脓肿住院患者资料,分析逐年住院费用变化、各项住院费用变化、各临床特征与住院费用的相关关系,多元逐步回归分析住院费用影响因素。结果 495例病例中,平均住院日为15.93 d,人均住院费用34 548.02元,所有项目费用中西药类占比最高;既往有肝胆手术史、肿瘤病史、治疗过程中合并胸腔积液、肺部感染、采用手术治疗患者住院费用显著升高(P<0.05);多因素回归分析提示住院天数越长、治疗手段越复杂、合并肿瘤史、出现胸腔积液患者住院费用更高。结论 2010-2019年住院治疗肝脓肿人均费用34 548.02元,其中西药费用占比最高,诊断类费用逐年增长,不同特征患者住院费用有差异。住院日、治疗手段、肿瘤史、合并胸腔积液均会对住院费用产生影响。  相似文献   
997.
本文对搭桥分流术中分流管端侧交接缝合处受力进行了分析,发现分流管向的张力随分流管面积与动脉管面积的比值增大而增大,并且在流量比为0.3时该张力有最小值。夹角的影响不大,但不可忽略。考虑到缝合材料等其它因素,还需建立对缝合线密度等因素的要求。  相似文献   
998.
Previous research in this laboratory, using photoactivatable radioiodinated lipopolysaccharide derivatized with sulfosuccinimidyl-2-(p-azidosalicylamide)-1,3'-dithiopropionate (125I-ASD-LPS), has resulted in the identification of a specific LPS receptor with a molecular mass of approximately 73 kDa on murine lymphocytes and splenic macrophages. The experiments presented in this report investigated whether a similar LPS-binding protein was also expressed on human peripheral blood populations, including monocytes, lymphocytes, neutrophils, platelets, and erythrocytes. Each cell population was incubated with 125I-ASD-LPS, UV irradiated, washed, reduced, and solubilized, and the cell lysates were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by autoradiography. On all of the cell populations, except erythrocytes, a similar 73-kDa LPS-binding protein was present. In addition, each population also expressed lower-molecular-weight secondary LPS-binding proteins, some of which were conserved among the populations. Binding of the photoactivatable LPS probe was found to be both time and temperature dependent. These data support the concept that the 73-kDa LPS-binding protein is conserved on multiple cell types from a variety of species.  相似文献   
999.
目的探讨引导组织再生性复合膜-纳米碳羟磷灰石/胶原/聚乳酸羟基乙酸复合膜(nCHAC/PLGA) 在体外的生物降解行为。方法根据牙周治疗的特点,功能分级材料nCHAC/PLGA膜制备成三层,即8wt% nCHAC PLGA/4wt%nCHAC PLGA/PLGA。其中一面为多孔结构,利于细胞在其上生长;另一面表面光滑,籍此抑制细胞的粘附。以纯聚乳酸羟基乙酸(PLGA)膜作为对照,将样本浸泡在37℃人工唾液中,比较两者生物降解行为。结果膜重量持续减轻,nCHAC/PLGA三层式功能分级复合膜在4周后重量减少23.1%, 12周后减少88%;单层纯聚乳酸羟基乙酸膜在4周后重量减轻30.7%,12周后减轻98.9%。处理4周后,因纳米碳羟磷灰石的降解,介质中钙离子浓度显著增加。另外,浸泡nCHAC/PLGA膜的溶液pH值略高于浸泡纯PLGA膜者,提示nCHAC复合物可能对溶液中PLGA酸性产物具中和作用。实验过程中,测试样本整体原形能维持4周,8周和12周时变成粉末状。扫描电镜结果显示,随着浸泡时间延长,膜的8wt% nCHAC PLGA多孔疏松面增加,PLGA致密光滑面亦出现小孔结构。结论复合膜的降解过程符合牙周修复的实际过程;此外,复合膜表面形成新的矿物结构,将对体内新骨再生起积极效应。  相似文献   
1000.
力作用下的细胞保护反应是细胞机械力转导研究中的一个重要领域。细胞膜维持细胞内离子平衡,并通过牵张活化离子通道和机械力敏感酶调控力诱导的细胞骨架重排对细胞骨架产生保护作用;而细胞骨架给细胞膜提供结构支撑、加强受力部分的皮层网络结构、调控机械力敏感离子通道,在受力破坏后的细胞膜重新封闭的过程中也发挥着潜在的作用。就细胞膜和细胞骨架在细胞受力过程中的保护作用进行综述。  相似文献   
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