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   1291132篇
  免费   95559篇
  国内免费   2080篇
耳鼻咽喉   18305篇
儿科学   42846篇
妇产科学   38258篇
基础医学   189602篇
口腔科学   35604篇
临床医学   110036篇
内科学   254163篇
皮肤病学   26842篇
神经病学   101102篇
特种医学   50374篇
外国民族医学   366篇
外科学   199485篇
综合类   26583篇
现状与发展   1篇
一般理论   321篇
预防医学   94328篇
眼科学   29313篇
药学   98732篇
  1篇
中国医学   2527篇
肿瘤学   69982篇
  2018年   12457篇
  2016年   10632篇
  2015年   12198篇
  2014年   16747篇
  2013年   25406篇
  2012年   35006篇
  2011年   37386篇
  2010年   21892篇
  2009年   20673篇
  2008年   36085篇
  2007年   39012篇
  2006年   39440篇
  2005年   38752篇
  2004年   37247篇
  2003年   36115篇
  2002年   35570篇
  2001年   58198篇
  2000年   59652篇
  1999年   50771篇
  1998年   14350篇
  1997年   12910篇
  1996年   13139篇
  1995年   12406篇
  1994年   11808篇
  1993年   10901篇
  1992年   41011篇
  1991年   40396篇
  1990年   39906篇
  1989年   38726篇
  1988年   36125篇
  1987年   35375篇
  1986年   33735篇
  1985年   32151篇
  1984年   23939篇
  1983年   20833篇
  1982年   12402篇
  1981年   10947篇
  1979年   22646篇
  1978年   15884篇
  1977年   13738篇
  1976年   12977篇
  1975年   14202篇
  1974年   16688篇
  1973年   16080篇
  1972年   15321篇
  1971年   14232篇
  1970年   13217篇
  1969年   12733篇
  1968年   11981篇
  1967年   10480篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
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   
3.
4.
5.
6.
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   
7.
8.
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