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71.
目的 分析成都市成年男性吸烟者吸烟行为、吸烟量及其变化的影响因素。方法对成都市两城区320名成年男性吸烟者面对面问卷调查。采用描述性分析、t检验、χ2检验、单因素方差分析、Kruskal-Wails H秩和检验、累积比数logistic回归方法分析数据。结果 分析显示吸烟者更换卷烟后, 吸烟量增加(t=2.327, P=0.021), 焦油量降低(t=-11.251, P<0.001);累积比数logistic回归分析显示, 学历较低(OR=1.968, P=0.040)、收入较高(OR=2.053, P=0.043)、烟蒂较短(OR=2.366, P=0.010)、尼古丁高依赖(OR=7.143, P<0.001)者吸烟量更大。结论 更换卷烟的吸烟者更倾向选择低焦油卷烟;学历低、收入高、尼古丁高依赖的吸烟者是控烟健康教育、行为干预的重点人群。 相似文献
72.
医师资格考试是大多数国家普遍采用的医师资格认证形式。医学人文的考核在医师资格考试中占有重要地位。以临床类别考试为例,通过文献分析、比较研究的方法,比较分析中美两国执业医师资格考试和医师资格分阶段考试实证研究考试中的医学人文考核,包括考试内容和形式、考试分值及比例。发现两国医学人文考核内容和比例基本相当,但我国现行考试医学人文考核站数较少,考试形式和呈现方式有待进一步改善,下一步应继续探索标准化病人应用于我国医师资格考试的可行性,充分发挥医师资格考试对医学教育的导向作用。 相似文献
73.
目的:建立专属性强的HPLC法测定安乃近片含量。方法:采用DiamonsilTMC18(200mm×4.6mm,5μm),以甲醇-缓冲液(磷酸二氢钠6.0g,加水溶解并稀释至1000ml,加三乙胺1ml,用浓氢氧化钠溶液调节pH值至7.0)(28∶72)作为流动相,检测波长为264nm,流速:1.0ml·min-1。结果:本色谱条件能将安乃近与4-去甲基安乃近及其他降解产物有效分离;在52.6~526μg·ml-1范围内,色谱峰面积与浓度呈良好的线性关系,r=0.99995;平均回收率为100.6%,(RSD=0.74%,n=9)。结论:本法专属性强、准确、简便,可供作为安乃近片含量修订的参考,尤其适用于疑似掺假安乃近片的含量测定。 相似文献
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75.
Ectasia and severe atherosclerosis: relationships with chlamydia pneumoniae, helicobacterpylori, and inflammatory markers 总被引:2,自引:0,他引:2
Adiloglu AK Can R Nazli C Ocal A Ergene O Tinaz G Kisioglu N 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》2005,32(1):21-27
To date, there has been no convincing evidence for an association between Chlamydia pneumoniae or Helicobacter pylori and ectasia. In this case-control study, we have investigated the association of H. pylori and C. pneumoniae seropositivity with ectasia, severe coronary atherosclerosis, and normal vessels, which were so classified by coronary angiography. We have also evaluated the influence of these infections on inflammatory markers such as high-sensitive C-reactive protein (hsCRP) and interleukin 6 (IL-6). Of the 796 patients undergoing coronary angiography for suspected ischemic heart disease, 244 patients were recruited. Of these, 91 had normal vessels, 88 had 3 or more obstructed vessels, and 65 had ectatic vessels without atherosclerosis. Eighty-seven atherosclerotic patients (98.9%) were positive for C. pneumoniae IgG, as were 64 ectatic patients (98.5%) and 76 controls (83.5%) (P < 0.001). Forty-two atherosclerotic patients (47.7%) were positive for C. pneumoniae IgM, as were 43 ectatic patients (66.2%) and 43 controls (47.3%) (P = 0.036). Seventy-two atherosclerotic patients (81.8%) were positive for H. pylori IgA, as were 26 ectatic patients (40.0%) and 44 controls (48.4%) (P < 0.001). High-sensitive CRP levels were significantly higher in ectatic patients (5.639 mg/L) than in controls (4.390 mg/L) (P = 0.032), and IL-6 levels were significantly higher in atherosclerotic patients (33.92 U/L) than in controls (14.01 U/L) (P < 0.001). Interleukin-6 levels were higher in H. pylori seropositive patients, and hsCRP levels were higher in C. pneumoniae seropositive patients, when compared with seronegatives. We suggest that, as in atherosclerosis, C. pneumoniae infection is related to ectasia, with raised CRP levels. 相似文献
76.
摘 要 目的: 建立核糖核酸类药物免疫活力测定方法。方法: 选用小鼠白细胞黏附抑制试验,对实验重要参数,如小鼠品系、药物作用浓度,黏附时间,缓冲液成分和细胞密度等进行探讨研究,初步建立了该类药物的免疫活力测定方法。并用该方法对核糖核酸Ⅰ、核糖核酸Ⅱ和核糖核酸Ⅲ各2批样品进行了免疫活力测定。结果: 确定了适合该类产品免疫活力测定方法的实验参数:小鼠品系对实验结果无影响,药物作用浓度为10 mg·ml-1,黏附时间为2 h,缓冲液中必须含钙镁离子,细胞密度约为4×107个/ml。用该方法对该类产品进行免疫活力测定,3次重复实验,结果均合格,RSD均低于20%。结论:白细胞黏附抑制试验可作为评价核糖核酸类药物免疫活力的方法。 相似文献
77.
Gozde Hasbal Tugba Yilmaz-Ozden Ayse Can 《Yao wu shi pin fen xi = Journal of food and drug analysis.》2015,23(1):57
In this study, the antioxidant and antiacetylcholinesterase activities of Sorbus torminalis (L.) Crantz fruits were evaluated. Total phenolic and flavonoid compounds, 2,2′-azino-bis (3-ethylbenzothioazoline-6-sulfonic acid), 2,2′-diphenyl-1-picrylhydrazyl, and superoxide anion radicals scavenging activities and ferric-reducing antioxidant power of water, ethyl acetate, acetone, and methanol extracts were determined for the measurement of the antioxidant activity. Quercetin and α-tocopherol were used as standard antioxidants. The inhibitory effect of the water extract on acetylcholinesterase (AChE) was evaluated using the Ellman method and galantamine was used as a standard. Water extract had the highest total phenolic concentration and the strongest antioxidant activity followed by ethyl acetate and acetone extracts whereas methanol extract has the lowest phenolics and weakest antioxidant activity. Moreover, water extract showed moderate ability to inhibit AChE. It was concluded that fruits of S. torminalis have antioxidant and anti-AChE activities and that the plant might be a natural source of antioxidants and AChE inhibitors. 相似文献
78.
Naked mole-rats maintain cardiac function and body composition well into their fourth decade of life
Can Emine Smith Megan Boukens Bastiaan J. Coronel Ruben Buffenstein Rochelle Riegler Johannes 《Age (Dordrecht, Netherlands)》2022,44(2):731-746
GeroScience - The prevalence of cardiovascular disease increases exponentially with age, highlighting the contribution of aging mechanisms to cardiac diseases. Although model organisms which share... 相似文献
79.
80.
Lei Tao Yuanbo Huang Xiaoqin Yang Yunwu Zheng Can Liu Mingwei Di Zhifeng Zheng 《RSC advances》2018,8(13):7102
Carbon nanofibers (CNFs) with excellent electrochemical performance represent a novel class of carbon nanostructures for boosting electrochemical applications, especially sustainable electrochemical energy conversion and storage applications. This work builds on an earlier study where the CNFs were prepared from a waste biomass (walnut shells) using a relatively simple procedure of liquefying the biomass, and electrospinning and carbonizing the fibrils. We further improved the mass ratio of the liquefying process and investigated the effects of the high temperature carbonization process at 1000, 1500 and 2000 °C, and comprehensively characterized the morphology, structural properties, and specific surface area of walnut shell-derived CNFs; and their electrochemical performance was also investigated as electrode materials in Li-ion batteries. Results demonstrated that the CNF anode obtained at 1000 °C exhibits a high specific capacity up to 271.7 mA h g−1 at 30 mA g−1, good rate capacity (131.3 and 102.2 mA h g−1 at 1 A g−1 and 2 A g−1, respectively), and excellent cycling performance (above 200 mA h g−1 specific capacity without any capacity decay after 200 cycles at 100 mA g−1). The present work demonstrates the great potential for converting low-cost biomass to high-value carbon materials for applications in energy storage.Carbon nanofibers (CNFs) with excellent electrochemical performance represent a novel class of carbon nanostructures for boosting electrochemical applications, especially sustainable electrochemical energy conversion and storage applications. 相似文献