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101.
目的:分析舒肺贴不同贴敷时间对慢性阻塞性肺疾病稳定期生存质量的影响,确定最佳贴敷时间。方法:采用多中心、随机、对照的临床试验设计,将164例慢性阻塞性肺疾病稳定期患者随机分为A组和B组,其中A组82例(贴敷6-8 h);B 组82例(贴敷8-12 h)。于夏季“三伏天”前的第10天、“三伏天”内的第1、10、20天,“三伏天”后的第10天各贴敷1次。研究结束后,脱落或剔除18例,本研究对符合研究要求的共146例(A组71例、B组75例)进行统计分析。结果:两组治疗后均能提高慢性阻塞性肺疾病稳定期患者的生存质量,但组间差异无统计学意义,患者贴敷6-8 h和贴敷8-12 h在治疗上均无统计学差异,但贴敷6-8 h严重大泡发生率低,安全性更好,选择6-8 h为最佳贴敷时间。结论:患者贴敷6-8 h和贴敷8-12 h在治疗上均无统计学差异,而贴敷8-12 h发生严重大泡率高,安全性较差,故舒肺贴最佳贴敷时间为6-8 h。  相似文献   
102.
BackgroundVideo-assisted thoracic surgery (VATS) is now the preferred approach for standard anatomical pulmonary resections. This study evaluates the impact of operative time (OT) on post-operative outcomes after VATS anatomical pulmonary resection for non-small cell lung cancer (NSCLC).MethodsWe retrospectively reviewed all consecutive patients undergoing VATS lobectomy or segmentectomy for NSCLC between November 2010 and December 2019. Postoperative outcomes were compared between short (<150 minutes) and long (≥150 minutes) OT groups. A multivariable analysis was performed to identify predictors of long OT and overall post-operative complications.ResultsA total of 670 patients underwent lobectomy (n=496, 74%) or segmentectomy (n=174, 26%) for NSCLC. Mediastinal lymph node dissection was performed in 621 patients (92.7%). The median OT was 141 minutes (SD: 47 minutes) and 387 patients (57.8%) were operated within 150 minutes. Neoadjuvant chemotherapy was given in 25 patients (3.7%). Conversion thoracotomy was realized in 40 patients (6%). Shorter OT was significantly associated with decreased post-operative overall complication rate (30% vs. 41%; P=0.003), shorter median length of drainage (3 vs. 4 days; P<0.001) and shorter median length of hospital stay (6 vs. 7 days; P<0.001). On multivariable analysis, long OT (≥150 minutes) (OR 1.64, P=0.006), ASA score >2 (OR 1.87, P=0.001), FEV1 <80% (OR 1.47, P=0.046) and DLCO <80% (OR 1.5, P=0.045) were significantly associated with postoperative complications. Two predictors of long OT were identified: neoadjuvant chemotherapy (OR 3.11, P=0.01) and lobectomy (OR 1.5, P=0.032).ConclusionsA prolonged OT is significantly associated with postoperative complications in our collective of patients undergoing VATS anatomical pulmonary resection.  相似文献   
103.
This work was mainly focused on the processing-parameter-related microstructure and properties of ultrafine WC-10Co-0.4VC-0.5Cr3C2 cemented carbide. The samples were prepared via a spark plasma sintering (SPS) technique using nano WC and Co powders and the corresponding inhibitor VC and Cr3C2 powders. The influence of the processing process on the microstructure and mechanical properties of ultrafine-grained cemented carbide was investigated under different ball-milling times and sintering temperatures. The results showed that the grain size of WC decreased with increasing ball-milling time and decreasing sintering temperature and that the specific gravity of ε-Co increased with increasing ball-milling time. The hardness of cemented carbide increased with increasing ball-milling time and decreased with increasing sintering temperature due to the corresponding variation in grain size and the relative density of samples. The transverse fracture strength (TRS) was mainly affected by ball-milling time. The increase in ball-milling time led to decreased TRS values, mainly ascribed to the formation of WC particle agglomeration and the decreased WC-Co eutectic temperature. In addition, temperature changes were found to have little effect on TRS. The samples sintered at 1250 °C with a ball-milling time of 60 h had comprehensive mechanical properties. Their average grain size, relative density, hardness, and TRS were 355.5 nm, 95.79%, 2035.5 kg/mm2, and 2155.99 MPa, respectively.  相似文献   
104.
Background and PurposeThe relationship between napping and cognition remains controversial. This study aimed to investigate the association between napping and cognition according to sleep debt in the Korean adult population.MethodsA population-based nationwide cross-sectional survey was conducted in 2018. A two-stage stratified random sample of Koreans aged ≥19 years was selected and evaluated using questionnaires by trained interviewers. Cognitive function was assessed using the Mail-In Cognitive Function Screening Instrument (MCFSI). Sleep habits on weekdays and weekends, napping, and subjective sleep requirements were assessed using the questionnaires. Accumulated sleep debt was calculated by subtracting the weekly average sleep duration from subjective sleep requirements. Sleep quality, daytime sleepiness, insomnia, depression, demographics, and comorbidities were assessed. Participants were grouped into those with sleep debt ≤60 min and those with sleep debt >60 min. Multiple linear regression was used to estimate the independent association between the factors and cognition.ResultsIn total, 2,501 participants were included in the analysis. Naps were reported in 726 (29.0%) participants (nappers). The mean MCFSI score was higher in nappers (3.4±3.6) than in non-nappers (2.3±3.0) (p<0.001). Multiple linear regression controlling for age, alcohol, smoking, depression, insomnia, daytime sleepiness, sleep quality, and education revealed that 30 to 60 min of napping was associated with worse cognitive function in participants with sleep debts ≤60 min, while >60 min of napping was associated with better cognitive function in participants with sleep debts >60 min.ConclusionsIn general, naps are associated with worse cognitive function in the Korean adult population. However, for those with sleep debt of >60 min, naps for >60 min were associated with better cognitive function.  相似文献   
105.
BackgroundSocially vulnerable communities are at increased risk for adverse health outcomes during a pandemic. Although this association has been established for H1N1, Middle East respiratory syndrome (MERS), and COVID-19 outbreaks, understanding the factors influencing the outbreak pattern for different communities remains limited.ObjectiveOur 3 objectives are to determine how many distinct clusters of time series there are for COVID-19 deaths in 3108 contiguous counties in the United States, how the clusters are geographically distributed, and what factors influence the probability of cluster membership.MethodsWe proposed a 2-stage data analytic framework that can account for different levels of temporal aggregation for the pandemic outcomes and community-level predictors. Specifically, we used time-series clustering to identify clusters with similar outcome patterns for the 3108 contiguous US counties. Multinomial logistic regression was used to explain the relationship between community-level predictors and cluster assignment. We analyzed county-level confirmed COVID-19 deaths from Sunday, March 1, 2020, to Saturday, February 27, 2021.ResultsFour distinct patterns of deaths were observed across the contiguous US counties. The multinomial regression model correctly classified 1904 (61.25%) of the counties’ outbreak patterns/clusters.ConclusionsOur results provide evidence that county-level patterns of COVID-19 deaths are different and can be explained in part by social and political predictors.  相似文献   
106.
本文通过小鼠应激反应实验证明:保龄麦胚美健丸对应激刺激具有保护作用,有抗疲劳、抗缺氧、耐寒之功效;本药可提高家兔单核—巨噬细胞系统的吞噬功能,延长凝血时间。  相似文献   
107.
基体辅助激光解吸质谱法在生物大分子质量研究中的应用   总被引:9,自引:0,他引:9  
研究了基体辅助激光解析飞行时间质谱法(MALDI-TOF MS)测定蛋白和糖蛋白的实验条件,实测了重组人白细胞介素2、肿瘤坏死因子、粒细胞巨噬细胞集落刺激因子、白细胞干扰素α2b、白细胞干扰素α1、促红细胞生成素、钙调蛋白及其片段、大鼠脑型一氧化氮合成酶和天然牛精液蛋白提取物的分子量和纯度,鉴定了蛋白质混合物中各单个成分,结果表明MALDI-TOF MS可有效地研究基因工程蛋白质和天然蛋白提取物等生物大分子的质量。  相似文献   
108.
109.
采用阿勒泰地区7个气象站1961—2010年逐日平均气温资料,使用线性趋势分析、累积距平、t检验并基于Kriging插值法,分析近50年日平均气温稳定通过≥10℃的初日、终日、持续日数和积温的时空变化特征,揭示春玉米播种期及种植布局的变化规律。结果表明,阿勒泰地区近50年≥10℃积温呈现初日提前、终日推迟、持续日数延长、积温增加的现象,其倾向率分别为0.3、1.3、1.6 d·10a-1和57.1℃·10a-1,且突变年份均发生在20世纪90年代中期。各县市春玉米播种期提前3~8 d,生长季延长6~11 d。突变前青河东部不能种植春玉米,晚熟品种不能种植或种植风险较大。随着气候不断变暖,春玉米不同熟性品种可种植区逐渐东扩,各县市春玉米在品种熟性上均发生了改变,表现为由不能种植到种植早熟、早熟向中(晚)熟、中晚熟向晚熟品种的变化。  相似文献   
110.
液相连续反应釜反应效果可如下进行预测。通过实验室装置测定并绘制拟定条件下的反应动力学曲线。把生产釜模拟为带死角和短路的理想釜,用水作介质在生产釜中进行流动模型试验,测量一系列停留时间分布密度函数,得到两个模型参数,并建立操作线方程。反应动力学曲线和操作线的交点为此液相连续反应釜的预测结果。  相似文献   
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