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   2524024篇
  免费   188347篇
  国内免费   4098篇
耳鼻咽喉   34126篇
儿科学   80699篇
妇产科学   66054篇
基础医学   371467篇
口腔科学   67195篇
临床医学   229550篇
内科学   493337篇
皮肤病学   54175篇
神经病学   202594篇
特种医学   93947篇
外国民族医学   498篇
外科学   381092篇
综合类   50176篇
现状与发展   12篇
一般理论   1115篇
预防医学   198498篇
眼科学   59195篇
药学   187409篇
  13篇
中国医学   4859篇
肿瘤学   140458篇
  2021年   22779篇
  2019年   23269篇
  2018年   31357篇
  2017年   23602篇
  2016年   26291篇
  2015年   29787篇
  2014年   42153篇
  2013年   62541篇
  2012年   87222篇
  2011年   92719篇
  2010年   54672篇
  2009年   51374篇
  2008年   86425篇
  2007年   91932篇
  2006年   92523篇
  2005年   90073篇
  2004年   85962篇
  2003年   82488篇
  2002年   79428篇
  2001年   110288篇
  2000年   112623篇
  1999年   95195篇
  1998年   29240篇
  1997年   25520篇
  1996年   25627篇
  1995年   24248篇
  1994年   22165篇
  1993年   20876篇
  1992年   72933篇
  1991年   70903篇
  1990年   69134篇
  1989年   66403篇
  1988年   61026篇
  1987年   59846篇
  1986年   55898篇
  1985年   53729篇
  1984年   40252篇
  1983年   34267篇
  1982年   20921篇
  1979年   36413篇
  1978年   26228篇
  1977年   21735篇
  1976年   20785篇
  1975年   22176篇
  1974年   26521篇
  1973年   25134篇
  1972年   23472篇
  1971年   22257篇
  1970年   20453篇
  1969年   19450篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
22.
23.
24.
25.
Gestational trophoblastic neoplasia (GTN) patients are treated according to the eight-variable International Federation of Gynaecology and Obstetrics (FIGO) scoring system, that aims to predict first-line single-agent chemotherapy resistance. FIGO is imperfect with one-third of low-risk patients developing disease resistance to first-line single-agent chemotherapy. We aimed to generate simplified models that improve upon FIGO. Logistic regression (LR) and multilayer perceptron (MLP) modelling (n = 4191) generated six models (M1-6). M1, all eight FIGO variables (scored data); M2, all eight FIGO variables (scored and raw data); M3, nonimaging variables (scored data); M4, nonimaging variables (scored and raw data); M5, imaging variables (scored data); and M6, pretreatment hCG (raw data) + imaging variables (scored data). Performance was compared to FIGO using true and false positive rates, positive and negative predictive values, diagnostic odds ratio, receiver operating characteristic (ROC) curves, Bland-Altman calibration plots, decision curve analysis and contingency tables. M1-6 were calibrated and outperformed FIGO on true positive rate and positive predictive value. Using LR and MLP, M1, M2 and M4 generated small improvements to the ROC curve and decision curve analysis. M3, M5 and M6 matched FIGO or performed less well. Compared to FIGO, most (excluding LR M4 and MLP M5) had significant discordance in patient classification (McNemar's test P < .05); 55-112 undertreated, 46-206 overtreated. Statistical modelling yielded only small gains over FIGO performance, arising through recategorisation of treatment-resistant patients, with a significant proportion of under/overtreatment as the available data have been used a priori to allocate primary chemotherapy. Streamlining FIGO should now be the focus.  相似文献   
26.
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   
27.
28.
29.
Maternal and Child Health Journal - Early life exposures can have an impact on a child’s developmental trajectory and children born late preterm (34–36&nbsp;weeks gestational age)...  相似文献   
30.
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