首页 | 本学科首页   官方微博 | 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   179篇
  免费   12篇
耳鼻咽喉   1篇
儿科学   2篇
妇产科学   2篇
基础医学   15篇
口腔科学   6篇
临床医学   7篇
内科学   28篇
皮肤病学   59篇
神经病学   24篇
外科学   16篇
预防医学   15篇
眼科学   5篇
药学   4篇
肿瘤学   7篇
  2023年   1篇
  2022年   2篇
  2021年   1篇
  2020年   1篇
  2019年   6篇
  2018年   5篇
  2017年   4篇
  2016年   1篇
  2015年   6篇
  2014年   8篇
  2013年   9篇
  2012年   8篇
  2011年   11篇
  2010年   1篇
  2009年   9篇
  2008年   10篇
  2007年   5篇
  2006年   12篇
  2005年   6篇
  2004年   5篇
  2003年   7篇
  2002年   2篇
  2001年   3篇
  2000年   10篇
  1999年   4篇
  1998年   3篇
  1997年   2篇
  1995年   1篇
  1994年   2篇
  1993年   3篇
  1992年   9篇
  1991年   7篇
  1990年   5篇
  1989年   5篇
  1988年   6篇
  1987年   2篇
  1986年   3篇
  1985年   3篇
  1979年   1篇
  1978年   2篇
排序方式: 共有191条查询结果,搜索用时 15 毫秒
1.
2.
The performance of two DNA line probe assays, a new version of INNO-LiPA Mycobacteria (Innogenetics, Ghent, Belgium) and the GenoType Mycobacterium (Hain Diagnostika, Nehren, Germany), were evaluated for identification of mycobacterial species isolated from liquid cultures. Both tests are based on a PCR technique and designed for simultaneous identification of different mycobacterial species by reverse hybridization and line probe technology. The INNO-LiPA Mycobacteria v2 targeting the 16S-23S rRNA gene spacer region was developed for the simultaneous identification of 16 different mycobacterial species. The GenoType Mycobacterium, which targets the 23S rRNA gene, allows simultaneous identification of 13 mycobacterial species. Both tests were evaluated on 110 mycobacterial strains belonging to 22 different mycobacterial species (20 reference strains, 83 clinical strains, and 4 Mycobacterium kansasii strains isolated from tap water) that were previously inoculated into MB/BacT bottles. The sensitivity of both methods, defined as the number of positive results obtained with the Mycobacterium genus probe together with an interpretable result on the number of samples tested was 110 of 110 (100%) for INNO-LiPA and 102 of 110 (92.7%) for GenoType. For samples with interpretable results, INNO-LiPA was able to correctly identify 109 of 110 samples (99.1%), whereas the GenoType correctly identified 100 of 102 samples (98.0%). Both tests were easy to perform, rapid, and reliable when applied to mycobacterial identification directly from MB/BacT bottles.  相似文献   
3.
4.
5.
6.
7.
Understanding the factors that determine the type and amount of formal care is important for predicting use in the future and developing long-term policy. In this context, we jointly analyze the provision of care at both the extensive (choice of care) and the intensive margin (number of hours of care received). In particular, we estimate and test, for the first time in this area of research, a sample selection model with the particularities that the first step is a multinomial logit model and the hours of care is an interval variable. Our results support the complementary and task-specific models which evidence has been found in other countries. Furthermore, we obtain evidence of substitution between formal and informal care for the male, young, married and unmarried subsamples. Regarding the hours of care, we find significant biases in predicted hours of care when sample selection is not taken into account. For the whole sample, the average bias is 2.77% for total hours and 3.23% for formal care hours. However, biases can be much larger (up to 10–15%), depending on the subsample and the type of care considered.  相似文献   
8.
Hip fracture rates in Norway rank among the highest in the world, more than double that of Spanish women. Previous studies were unable to demonstrate significant differences between the two populations with respect to bone mass or calcium metabolism. In order to test whether the difference in fracture propensity between both populations could be explained by differences in bone material quality we assessed bone material strength using microindentation in 42 Norwegian and 46 Spanish women with normal BMD values, without clinical or morphometric vertebral fractures, no clinical or laboratory signs of secondary osteoporosis, and without use of drugs with known influence on bone metabolism. Bone material properties were assessed by microindentation of the thick cortex of the mid tibia following local anesthesia of the area using the Osteoprobe device (Active Life Scientific, Santa Barbara, CA, USA). Indentation distance was standardized against a calibration phantom of methylmethacrylate and results, as percentage of this reference value, expressed as bone material strength index units (BMSi). We found that the bone material properties reflected in the BMSi value of Norwegian women was significantly inferior when compared to Spanish women (77 ± 7.1 versus 80.7 ± 7.8, p < 0.001). Total hip BMD was significantly higher in Norwegian women (1.218 g/cm2 versus 0.938 g/cm2, p < 0.001) but regression analysis revealed that indentation values did not vary with BMD r2 = 0.03 or age r2 = 0.04. In conclusion Norwegian women show impaired bone material properties, higher bone mass, and were taller than Spanish women. The increased height will increase the impact on bone after falls, and impaired bone material properties may further enhance the risk fracture after such falls. These ethnic differences in bone material properties may partly explain the higher propensity for fracture in Norwegian women. © 2015 American Society for Bone and Mineral Research.  相似文献   
9.
10.
Since the coronavirus disease pandemic response began in March 2020, tests, vaccinations, diagnoses, and treatment initiations for sexual health, HIV, and viral hepatitis in England have declined. The shift towards online and outreach services happened rapidly during 2020 and highlights the need to evaluate the effects of these strategies on health inequalities.  相似文献   
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