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   1363433篇
  免费   100854篇
  国内免费   2473篇
耳鼻咽喉   19268篇
儿科学   44528篇
妇产科学   39358篇
基础医学   198540篇
口腔科学   37613篇
临床医学   116948篇
内科学   270223篇
皮肤病学   27909篇
神经病学   107688篇
特种医学   53592篇
外国民族医学   367篇
外科学   212179篇
综合类   27416篇
现状与发展   1篇
一般理论   502篇
预防医学   98960篇
眼科学   30704篇
药学   103292篇
  1篇
中国医学   2612篇
肿瘤学   75059篇
  2018年   14928篇
  2017年   11078篇
  2016年   12386篇
  2015年   14197篇
  2014年   19602篇
  2013年   29023篇
  2012年   40568篇
  2011年   43051篇
  2010年   25238篇
  2009年   23476篇
  2008年   40919篇
  2007年   43662篇
  2006年   44067篇
  2005年   43214篇
  2004年   41293篇
  2003年   39837篇
  2002年   38974篇
  2001年   58786篇
  2000年   60170篇
  1999年   51403篇
  1998年   15110篇
  1997年   13499篇
  1996年   13652篇
  1995年   12919篇
  1994年   12212篇
  1993年   11316篇
  1992年   41365篇
  1991年   40708篇
  1990年   40208篇
  1989年   39041篇
  1988年   36435篇
  1987年   35659篇
  1986年   34040篇
  1985年   32442篇
  1984年   24250篇
  1983年   21120篇
  1982年   12674篇
  1981年   11225篇
  1979年   22794篇
  1978年   16055篇
  1977年   13877篇
  1976年   13092篇
  1975年   14325篇
  1974年   16812篇
  1973年   16185篇
  1972年   15450篇
  1971年   14340篇
  1970年   13305篇
  1969年   12794篇
  1968年   12039篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
2.
3.
Intratumor heterogeneity is a main cause of the dismal prognosis of glioblastoma (GBM). Yet, there remains a lack of a uniform assessment of the degree of heterogeneity. With a multiscale approach, we addressed the hypothesis that intratumor heterogeneity exists on different levels comprising traditional regional analyses, but also innovative methods including computer-assisted analysis of tumor morphology combined with epigenomic data. With this aim, 157 biopsies of 37 patients with therapy-naive IDH-wildtype GBM were analyzed regarding the intratumor variance of protein expression of glial marker GFAP, microglia marker Iba1 and proliferation marker Mib1. Hematoxylin and eosin stained slides were evaluated for tumor vascularization. For the estimation of pixel intensity and nuclear profiling, automated analysis was used. Additionally, DNA methylation profiling was conducted separately for the single biopsies. Scoring systems were established to integrate several parameters into one score for the four examined modalities of heterogeneity (regional, cellular, pixel-level and epigenomic). As a result, we could show that heterogeneity was detected in all four modalities. Furthermore, for the regional, cellular and epigenomic level, we confirmed the results of earlier studies stating that a higher degree of heterogeneity is associated with poorer overall survival. To integrate all modalities into one score, we designed a predictor of longer survival, which showed a highly significant separation regarding the OS. In conclusion, multiscale intratumor heterogeneity exists in glioblastoma and its degree has an impact on overall survival. In future studies, the implementation of a broadly feasible heterogeneity index should be considered.  相似文献   
4.
5.
6.
7.
Jones type fifth metatarsal fractures pose a challenge to the foot and ankle surgeon, given documented high nonunion rates as well as high complication rates including hardware prominence, nerve injury, and screw breakage for existing treatment modalities including screw and plantar plate fixation. We call for the design of innovative Jones-fracture specific implants which contour to the natural curve of the fifth metatarsal. Future research should aim to expand upon existing literature for Jones fracture fixation and evaluate efficacy of novel implants which are designed to address unacceptably high complication rates for existing treatment modalities.  相似文献   
8.
Vaccination is a vital health care initiative to prevent individual and population infection. To increase vaccination rates the federal government implemented the ‘No Jab, No Pay’ policy, where eligibility for several government benefits required children to be fully vaccinated by removing ‘conscientious objections’ and expanding the age range of children whose families receive benefits. This study assesses the impact of this policy at a local area within a single medical practice community in NSW, Australia. A retrospective clinical audit was performed between 2012 and 2017 on a single general practice's vaccination records for children ≤19 years. Catch-up vaccinations were assessed based on age at vaccination. Incidence of catch-up vaccinations was assessed for each of four years before and two years after the implementation of the ‘No Jab, No Pay’ policy in January 2016, along with the age of children and vaccination(s) given. Catch-up vaccinations were assessed temporally either side of implementation of ‘No Jab, No Pay’. Comparing the average annual vaccination catch-up incidence rate of 6.2% pre-implementation (2012–2015), there was an increase to 9.2% in 2016 (p < .001) and 7.8% in 2017 (p = .027). Secondary outcome measurement of catch-up vaccination incidence rates before (2012–2015) and after (2016–2017) ‘No Jab, No Pay’ implementation showed statistically significant increases for children aged 8–11 years (3.2%–5.6%, p = .038), 12–15 years (7.5%–14.7%, p < .001) and 16–19 years (3.3%–10.2%, p < .001) along with a statistically significant reduction in children aged 1–3 years (11.4%–6.2%, p = .015). Also, catch-up rates for DTPa significantly increased after program implementation. This study demonstrates that the Australian federal government vaccination policy ‘No Jab, No Pay’ was coincident with an increase in catch-up vaccinations within a rural NSW community served by one medical practice, especially for older children.  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