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   17363篇
  免费   1099篇
  国内免费   47篇
耳鼻咽喉   209篇
儿科学   359篇
妇产科学   459篇
基础医学   2842篇
口腔科学   434篇
临床医学   1789篇
内科学   3193篇
皮肤病学   341篇
神经病学   1654篇
特种医学   875篇
外科学   2628篇
综合类   116篇
一般理论   2篇
预防医学   903篇
眼科学   569篇
药学   1195篇
中国医学   56篇
肿瘤学   885篇
  2023年   63篇
  2021年   245篇
  2020年   155篇
  2019年   295篇
  2018年   336篇
  2017年   285篇
  2016年   345篇
  2015年   362篇
  2014年   498篇
  2013年   724篇
  2012年   987篇
  2011年   983篇
  2010年   666篇
  2009年   624篇
  2008年   974篇
  2007年   1053篇
  2006年   1065篇
  2005年   1080篇
  2004年   892篇
  2003年   880篇
  2002年   856篇
  2001年   175篇
  2000年   123篇
  1999年   161篇
  1998年   161篇
  1997年   126篇
  1996年   117篇
  1995年   143篇
  1994年   111篇
  1993年   117篇
  1992年   95篇
  1991年   82篇
  1990年   77篇
  1988年   70篇
  1985年   67篇
  1984年   85篇
  1983年   62篇
  1982年   91篇
  1981年   82篇
  1933年   97篇
  1932年   93篇
  1931年   81篇
  1930年   83篇
  1929年   76篇
  1928年   78篇
  1927年   69篇
  1926年   80篇
  1924年   77篇
  1923年   76篇
  1922年   61篇
排序方式: 共有10000条查询结果,搜索用时 125 毫秒
1.
Similar family-based cancer and genealogy data from Norway and Utah allowed comparisons of the incidence of testicular cancer (TC), and exploration of the role of Scandinavian ancestry and family history of TC in TC risk. Our study utilizes data from the Utah Population Database and Norwegian Population Registers. All males born during 1951–2015 were followed for TC until the age of 29 years. A total of 1,974,287 and 832,836 males were born in Norway and Utah, respectively, of whom 2,686 individuals were diagnosed with TC in Norway and 531 in Utah. The incidence per year of TC in Norway (10.6) was twice that observed in Utah (5.1) for males born in the last period (1980–1984). The incidence rates of TC in Utah did not differ according to the presence or absence of Scandinavian ancestry (p = 0.669). Having a brother diagnosed with TC was a strong risk factor for TC among children born in Norway and Utah, with HR = 9.87 (95% CI 5.68–17.16) and 6.02 (95% CI 4.80–7.55), respectively; with even higher HR observed among the subset of children in Utah with Scandinavian ancestry (HR = 12.30, 95% CI 6.78–22.31). A clear difference in TC incidence among individuals born in Norway and descendants of Scandinavian people born in Utah was observed. These differences in TC rates point to the possibility of environmental influence. Family history of TC is a strong risk factor for developing TC in both populations.  相似文献   
2.
3.
4.
5.

Background

Nursing Home Compare (NHC) ratings, created and maintained by Medicare, are used by both hospitals and consumers to aid in the skilled nursing facility (SNF) selection process. To date, no studies have linked NHC ratings to actual episode-based outcomes. The purpose of this study was to evaluate whether NHC ratings are valid predictors of 90-day complications, readmission, and bundle costs for patients discharged to an SNF after primary total joint arthroplasty (TJA).

Methods

All SNF-discharged primary TJA cases in 2017 at a multihospital academic health system were queried. Demographic, psychosocial, and clinical variables were manually extracted from the health record. Medicare NHC ratings were then collected for each SNF. For patients in the Medicare bundle, postacute and total bundle cost was extracted from claims.

Results

Four hundred eighty-eight patients were discharged to a total of 105 unique SNFs. In multivariate analysis, overall NHC rating was not predictive of 90-day readmission/major complications, >75th percentile postacute cost, or 90-day bundle cost exceeding the target price. SNF health inspection and quality measure ratings were also not predictive of 90-day readmission/major complications or bundle performance. A higher SNF staffing rating was independently associated with a decreased odds for >75th percentile 90-day postacute spend (odds ratio, 0.58; P = .01) and a 90-day bundle cost exceeding the target price (odds ratio = 0.69; P = .02) but was similarly not predictive of 90-day readmission/complications.

Conclusion

Results of our study suggest that Medicare's NHC tool is not a useful predictor of 90-day costs, complications, or readmissions for SNFs within our health system.  相似文献   
6.
PurposeUnderstanding the value of genetic screening and testing for monogenic disorders requires high-quality, methodologically robust economic evaluations. This systematic review sought to assess the methodological quality among such studies and examined opportunities for improvement.MethodsWe searched PubMed, Cochrane, Embase, and Web of Science for economic evaluations of genetic screening/testing (2013-2019). Methodological rigor and adherence to best practices were systematically assessed using the British Medical Journal checklist.ResultsAcross the 47 identified studies, there were substantial variations in modeling approaches, reporting detail, and sophistication. Models ranged from simple decision trees to individual-level microsimulations that compared between 2 and >20 alternative interventions. Many studies failed to report sufficient detail to enable replication or did not justify modeling assumptions, especially for costing methods and utility values. Meta-analyses, systematic reviews, or calibration were rarely used to derive parameter estimates. Nearly all studies conducted some sensitivity analysis, and more sophisticated studies implemented probabilistic sensitivity/uncertainty analysis, threshold analysis, and value of information analysis.ConclusionWe describe a heterogeneous body of work and present recommendations and exemplar studies across the methodological domains of (1) perspective, scope, and parameter selection; (2) use of uncertainty/sensitivity analyses; and (3) reporting transparency for improvement in the economic evaluation of genetic screening/testing.  相似文献   
7.
8.
AIDS and Behavior - Male partner involvement (MPI) during the prenatal and postnatal periods has been proven to have a beneficial effect on infant development. Infants born to HIV seropositive...  相似文献   
9.
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