首页 | 官方网站   微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   215篇
  免费   10篇
医药卫生   225篇
  2023年   1篇
  2022年   4篇
  2021年   5篇
  2020年   1篇
  2019年   11篇
  2018年   15篇
  2017年   11篇
  2016年   5篇
  2015年   10篇
  2014年   19篇
  2013年   16篇
  2012年   11篇
  2011年   19篇
  2010年   8篇
  2009年   8篇
  2008年   5篇
  2007年   8篇
  2006年   6篇
  2005年   8篇
  2004年   5篇
  2003年   10篇
  2002年   1篇
  2001年   4篇
  2000年   3篇
  1999年   7篇
  1998年   3篇
  1997年   4篇
  1996年   3篇
  1995年   2篇
  1994年   3篇
  1993年   1篇
  1992年   1篇
  1991年   1篇
  1990年   1篇
  1988年   2篇
  1985年   1篇
  1981年   1篇
  1978年   1篇
排序方式: 共有225条查询结果,搜索用时 31 毫秒
1.
目的 观察病毒性脑炎急性和恢复期患者血液和脑脊液的S-100b蛋白浓度变化,探讨其与异常脑电图和影像学低密度灶体积等方面的相关性。方法 42例病毒性脑炎住院患者为观察组,25例与观察组相匹配的阑尾或胆囊摘除手术病人以及健康体检者为对照组,采用双抗体夹心ELISA法,检测其血液及脑脊液100b蛋白浓度;并应用SPSS10.0统计软件包进行统计学分析。结果病毒性脑炎急性期患者血液和脑脊液S-100b蛋白显著高于恢复期患者和对照组(P〈0.01);血液和脑脊液S-100b蛋白浓度与低密度灶体积均呈显著正相关(rCSF=0.756,P〈0.01;r血液=0.685,P〈0.01);轻度、中度及重度异常脑电图患者脑脊液S-100b蛋白浓度均高于血液(P〈0.01);重度、中度异常脑电图患者血液及脑脊液S-100b蛋白浓度均高于轻度(P〈0.01)。结论脑脊液或血液中的S-100b蛋白浓度反映了神经胶质细胞的损害程度,也是脑组织破坏后较合适的生化标记物,对监测病毒性脑炎患者的病情变化和疗效观察具有重要价值。  相似文献   
2.
p21-ras、p53和VEGF在甲状腺乳头状癌中的表达及意义   总被引:3,自引:0,他引:3  
目的 研究原癌基因Ras、抑癌基因p5 3及血管内皮生长因子 (VEGF)在甲状腺乳头状癌中的表达及相关性。方法 应用免疫组织化学S P法对 4 0例甲状腺乳头状癌中p2 1 ras、p5 3及VEGF的表达进行研究。结果 甲状腺乳头状癌中存在p2 1 ras、p5 3及VEGF的过度表达 ;VEGF的表达与p2 1 ras、p5 3的表达显著相关 (P <0 .0 5 ) ;VEGF的表达与甲状腺乳头状癌淋巴结转移显著相关 (P <0 .0 5 )。结论 p2 1 ras、p5 3、VEGF在甲状腺乳头状癌的发生发展过程中起重要作用 ;VEGF的表达与p2 1 ras、p5 3表达显著相关 ,可能受其调控。  相似文献   
3.
营养素防护同型半胱氨酸致ECV304细胞损伤和凋亡   总被引:1,自引:0,他引:1  
高键  薛安娜 《营养学报》2004,26(3):192-195
目的: 探讨叶酸、维生素E(VE)和硒(Se)对同型半胱氨酸(homocysteine, Hcy)诱导ECV304细胞损伤和凋亡的防护作用及其机制。方法: 采用倒置显微镜观察和MTT实验检测各种营养素对Hcy细胞损伤作用的防护,采用琼脂糖凝胶DNA电泳和流式细胞仪检测各种营养素对Hcy诱导细胞凋亡作用的防护。并通过测定细胞内脂质过氧化水平、细胞内抗氧化酶活力及对细胞内活性氧产生的改变研究其保护机制。结果: 叶酸、VE和Se都可防护Hcy的细胞增殖抑制和诱导细胞凋亡作用,并都可明显减少细胞内MDA含量。叶酸可以明显增加细胞内SOD活力,叶酸和Se可以明显增加细胞内GSH-Px活力。VE对Hcy诱导的细胞内活性氧产生具有明显抑制作用,而Se和叶酸抑制作用不明显。结论: 叶酸、VE和Se都可以防护Hcy导致的细胞增殖抑制,并可以抑制Hcy诱导的细胞凋亡,但其作用机制不同。  相似文献   
4.
蛇床子素抗氧自由基清除作用的研究   总被引:3,自引:1,他引:3  
王书华  安芳  张丹参 《中成药》2004,26(12):1062-1063
蛇床子素(Osthole)是从伞形科植物蛇床成熟果实蛇床子中提取的一种生物活性较高的香豆素.实验证明,蛇床子素可显著提高AlCl3致衰老模型小鼠的SOD和GSH-PX活性以及降低大鼠肝、脑组织过氧化脂质含量[1,2].为进一步探讨其抗衰老的作用机制,我们对蛇床子素的抗氧自由基作用进行了体外试验并与VE相比较.  相似文献   
5.
6.
7.
《Vaccine》2015,33(24):2813-2822
BackgroundIn the first five I-MOVE (Influenza Monitoring Vaccine Effectiveness in Europe) influenza seasons vaccine effectiveness (VE) results were relatively homogenous among participating study sites. In 2013–2014, we undertook a multicentre case-control study based on sentinel practitioner surveillance networks in six European Union (EU) countries to measure 2013–2014 influenza VE against medically-attended influenza-like illness (ILI) laboratory-confirmed as influenza. Influenza A(H3N2) and A(H1N1)pdm09 viruses co-circulated during the season.MethodsPractitioners systematically selected ILI patients to swab within eight days of symptom onset.We compared cases (ILI positive to influenza A(H3N2) or A(H1N1)pdm09) to influenza negative patients. We calculated VE for the two influenza A subtypes and adjusted for potential confounders. We calculated heterogeneity between sites using the I2 index and Cochrane's Q test. If the I2 was <50%, we estimated pooled VE as (1 minus the OR) × 100 using a one-stage model with study site as a fixed effect. If the I2 was >49% we used a two-stage random effects model.ResultsWe included in the A(H1N1)pdm09 analysis 531 cases and 1712 controls and in the A(H3N2) analysis 623 cases and 1920 controls. For A(H1N1)pdm09, the Q test (p = 0.695) and the I2 index (0%) suggested no heterogeneity of adjusted VE between study sites. Using a one-stage model, the overall pooled adjusted VE against influenza A(H1N1)pdm2009 was 47.5% (95% CI: 16.4–67.0).For A(H3N2), the I2 was 51.5% (p = 0.067). Using a two-stage model for the pooled analysis, the adjusted VE against A(H3N2) was 29.7 (95% CI: −34.4–63.2).ConclusionsThe results suggest a moderate 2013–2014 influenza VE against A(H1N1)pdm09 and a low VE against A(H3N2). The A(H3N2) estimates were heterogeneous among study sites. Larger sample sizes by study site are needed to prevent statistical heterogeneity, decrease variability and allow for two-stage pooled VE for all subgroup analyses.  相似文献   
8.
《Vaccine》2015,33(2):367-373
BackgroundIn 2013–2014 Greece experienced a resurgence of severe influenza cases, coincidental with a shift to H1N1pdm09 predominance. We sought to estimate Vaccine Effectiveness (VE) for this season using available surveillance data from hospitals (including both inpatients and outpatients).MethodsSwab samples were sent by hospital physicians to one of three laboratories, covering the entire country, to be tested for influenza using RT-PCR. The test-negative design was employed, with patients testing positive serving as cases and those testing negative serving as controls. VE was estimated using logistic regression, adjusted for age group, sex, region and calendar time, with further adjustment for unknown vaccination status using inverse response propensity weights. Additional age group stratified estimates and subgroup estimates of VE against H1N1pdm09 and H3N2 were calculated.ResultsOut of 1310 patients with known vaccination status, 124 (9.5%) were vaccinated, and 543 patients (41.5%) tested positive for influenza. Adjusted VE was 34.5% (95% CI: 4.1–55.3%) against any influenza, and 56.7% (95% CI: 22.8–75.7%) against H1N1pdm09. VE estimates appeared to be higher for people aged 60 and older, while in those under 60 there was limited evidence of effectiveness. Isolated circulating strains were genetically close to the vaccine strain, with limited evidence of antigenic drift.ConclusionsThese results suggest a moderate protective effect of the 2013–2014 influenza vaccine, mainly against H1N1pdm09 and in people aged 60 and over. Vaccine coverage was very low in Greece, even among groups targeted for vaccination, and substantial efforts should be made to improve it. VE can and should be routinely monitored, and the results taken into account when deciding on influenza vaccine composition for next season.  相似文献   
9.
Papillary thyroid carcinoma (PTC) is the most common endocrine malignancy among other endocrine tumors, and BRAF V600E is a frequent genetic mutation occurring in the disease. Although different molecular techniques, most importantly sequencing has been widely recognized as a gold standard but molecular diagnosis remains an expensive, laborious, and time‐intensive process. Recently, immunohistochemistry (IHC) with anti‐BRAF V600E (VE1) antibody has increased practical utility and implemented clinically for the detection of BRAF V600E mutation. Therefore, the study aimed to evaluate diagnostic accuracy of VE1 IHC for detecting the BRAF V600E mutation frequency and clinical implementation in diagnostic laboratories. In this study, 72 formalin fixed paraffin‐embedded tissues (FFPE) were used to determine the BRAF V600E mutation status using IHC and Sanger sequencing. The mutation was found in 29% and 28% cases using IHC and Sanger sequencing, respectively. Furthermore, the results showed 100% sensitivity, 98.07% specificity, 95.2% positive predictive value, and 100% negative predictive value. Notably, significant associations were found between BRAF V600E status and tumor stage, tumor focality, and extrathyroidal extensions, respectively. VE1 IHC was found to be a highly sensitive, specific, and diagnostically accurate method in this cohort. Therefore, BRAF V600E detection through IHC has been considered as the best tailored technique for routine pathology laboratories.  相似文献   
10.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司    京ICP备09084417号-23

京公网安备 11010802026262号