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   1326985篇
  免费   98986篇
  国内免费   5162篇
耳鼻咽喉   18708篇
儿科学   42757篇
妇产科学   38440篇
基础医学   193684篇
口腔科学   36425篇
临床医学   114591篇
内科学   259090篇
皮肤病学   27200篇
神经病学   101964篇
特种医学   52370篇
外国民族医学   403篇
外科学   203311篇
综合类   34138篇
现状与发展   8篇
一般理论   302篇
预防医学   95707篇
眼科学   30513篇
药学   103098篇
  44篇
中国医学   5158篇
肿瘤学   73222篇
  2018年   13697篇
  2017年   10520篇
  2016年   11792篇
  2015年   14143篇
  2014年   19144篇
  2013年   27170篇
  2012年   38059篇
  2011年   40560篇
  2010年   24157篇
  2009年   22422篇
  2008年   38057篇
  2007年   40920篇
  2006年   41241篇
  2005年   40312篇
  2004年   38178篇
  2003年   37015篇
  2002年   36363篇
  2001年   59163篇
  2000年   60646篇
  1999年   51754篇
  1998年   14848篇
  1997年   13471篇
  1996年   13596篇
  1995年   12793篇
  1994年   12115篇
  1993年   11105篇
  1992年   41283篇
  1991年   40577篇
  1990年   40073篇
  1989年   38878篇
  1988年   36239篇
  1987年   35454篇
  1986年   33808篇
  1985年   32203篇
  1984年   23968篇
  1983年   20854篇
  1982年   12391篇
  1981年   10949篇
  1979年   22653篇
  1978年   15887篇
  1977年   13733篇
  1976年   12974篇
  1975年   14204篇
  1974年   16690篇
  1973年   16087篇
  1972年   15321篇
  1971年   14238篇
  1970年   13221篇
  1969年   12740篇
  1968年   11976篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
Journal of Behavioral Medicine - Evidence supports the use of graphic warnings to educate the public about the health harms of smoking and suggests warnings eliciting negative emotional responses...  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.
Odontology - To investigate the characterization and function of a novel porous osteogenic material (PLLA / DDM) containing polylactic acid and demineralized dentin matrix. The surface morphology...  相似文献   
8.
9.
G. Berlin  M. Hammar  L. Tapper 《Platelets》2019,30(4):473-479
Platelets are needed to prevent or arrest bleeding and aggregate at the site of injury upon vascular damage. Platelets express receptors for estrogens which might affect the function of the platelets and their hemostatic ability. The aim was to identify possible differences in platelet function related to age, gender, and phases of the menstrual cycle by use of impedance aggregometry with Multiplate. In the first part of the study, platelet function was assessed in 60 healthy individuals (30 men and 30 women) in each of three age groups (20–25, 40–45, and 60–65 years). In the second part of the study, the platelet function was analyzed on four occasions during the menstrual cycle in women without oral contraceptives (OCs) (n = 17) and compared to 19 women on OCs and 18 men of similar age (20–40 years). For the women on OCs, aggregation was analyzed once during the tablet-free week and once late during the period with OCs. The men were sampled once. Women of younger age (<45 years) had significantly higher agonist-induced aggregation response than both men and post-menopausal women (60–65 years). The agonist-induced aggregation response did not differ between phases of the menstrual cycle or OC use. The results suggest that estradiol and/or progesterone affect spontaneous aggregation since it was found to be lowest in the mid-luteal phase. Spontaneous aggregation was significantly lower in women on OCs than in both men and women without OCs. Our findings indicate that fertile age is associated with higher aggregation response capacity of the platelets, possibly to prevent excessive bleeding during menstruation, but this response capacity is not altered during the menstrual cycle or by use of OCs.  相似文献   
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