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   1288444篇
  免费   95430篇
  国内免费   2454篇
耳鼻咽喉   18350篇
儿科学   42504篇
妇产科学   38157篇
基础医学   188772篇
口腔科学   35661篇
临床医学   109705篇
内科学   253647篇
皮肤病学   26782篇
神经病学   100126篇
特种医学   50570篇
外国民族医学   369篇
外科学   199192篇
综合类   27613篇
现状与发展   1篇
一般理论   302篇
预防医学   93375篇
眼科学   29421篇
药学   98994篇
  5篇
中国医学   2828篇
肿瘤学   69954篇
  2018年   12215篇
  2016年   10420篇
  2015年   12133篇
  2014年   16594篇
  2013年   24996篇
  2012年   34616篇
  2011年   37071篇
  2010年   21885篇
  2009年   20572篇
  2008年   35787篇
  2007年   38755篇
  2006年   39274篇
  2005年   38521篇
  2004年   37022篇
  2003年   35918篇
  2002年   35393篇
  2001年   58478篇
  2000年   59943篇
  1999年   51031篇
  1998年   14376篇
  1997年   12952篇
  1996年   13244篇
  1995年   12482篇
  1994年   11860篇
  1993年   10935篇
  1992年   41144篇
  1991年   40507篇
  1990年   40013篇
  1989年   38826篇
  1988年   36205篇
  1987年   35438篇
  1986年   33805篇
  1985年   32219篇
  1984年   23988篇
  1983年   20866篇
  1982年   12419篇
  1981年   10968篇
  1979年   22678篇
  1978年   15915篇
  1977年   13752篇
  1976年   12988篇
  1975年   14224篇
  1974年   16718篇
  1973年   16093篇
  1972年   15322篇
  1971年   14234篇
  1970年   13218篇
  1969年   12729篇
  1968年   11985篇
  1967年   10471篇
排序方式: 共有10000条查询结果,搜索用时 281 毫秒
1.
2.
3.
4.
5.
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   
6.
7.
Inappropriate use of acetaminophen (APAP) can lead to morbidity and mortality secondary to hepatic necrosis. Ginsenoside Rg1 is a major active ingredient in processed Panax ginseng, which is proved to elicit biological effects. We hypothesized the beneficial effect of Rg1 on APAP-mediated hepatotoxicity was through Nrf2/ARE pathway. The study was conducted in cells and mice, comparing the actions of Rg1. Rg1 significantly improved cell survival rates and promoted the expression of antioxidant proteins. Meanwhile, Rg1 reduced the excessive ROS and the occurrence of cell apoptosis, which were related to Nrf2/ARE pathway. Expression of Nrf2 has a certain cell specificity.

  相似文献   

8.
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   
9.
10.
Introduction: The treatment of classical Hodgkin lymphoma (cHL) in children is a story of success. Nowadays, more than 90% of patients are cured and overall survival is nearly 100% at 5 years. Efforts have been made to avoid related effects of therapies; therefore, children are treated using different chemotherapy schemes in comparison with adults.

Areas covered: This review includes a view of the clinical classification and risk assessment in children suffering from HL. The chemotherapy more commonly employed is revisited. The use of PET/CT to evaluate the disease in order to guide therapy is analyzed. New options of chemotherapy and emerging immunotherapy are also included.

Expert opinion: In order to make the right treatment choice, a proper initial assessment of risk is mandatory. The choice of therapy in these kinds of patients must be done according to the experience of the team, and also, the cost and logistics related to the eligible scheme are very important. If possible, efforts must be made to include PET/CT in guiding therapy and avoiding overtreatment and long-term adverse effects in children. New options in immunotherapy are emerging and must be considered with caution in selected patients.  相似文献   

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