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   3356554篇
  免费   246897篇
  国内免费   8543篇
耳鼻咽喉   46442篇
儿科学   112321篇
妇产科学   93093篇
基础医学   472443篇
口腔科学   92426篇
临床医学   304904篇
内科学   660442篇
皮肤病学   78482篇
神经病学   273017篇
特种医学   130204篇
外国民族医学   1282篇
外科学   505536篇
综合类   69784篇
现状与发展   6篇
一般理论   1221篇
预防医学   257630篇
眼科学   75870篇
药学   247495篇
  9篇
中国医学   6787篇
肿瘤学   182600篇
  2019年   25882篇
  2018年   36591篇
  2017年   28017篇
  2016年   32179篇
  2015年   36272篇
  2014年   50022篇
  2013年   75559篇
  2012年   101067篇
  2011年   107117篇
  2010年   64621篇
  2009年   61794篇
  2008年   100543篇
  2007年   107048篇
  2006年   108585篇
  2005年   104527篇
  2004年   101127篇
  2003年   97686篇
  2002年   94586篇
  2001年   161234篇
  2000年   165695篇
  1999年   140204篇
  1998年   40212篇
  1997年   35785篇
  1996年   35985篇
  1995年   34699篇
  1994年   32156篇
  1993年   30135篇
  1992年   110100篇
  1991年   106359篇
  1990年   103301篇
  1989年   99743篇
  1988年   91545篇
  1987年   89838篇
  1986年   84048篇
  1985年   80313篇
  1984年   60042篇
  1983年   50844篇
  1982年   29908篇
  1981年   26993篇
  1979年   53338篇
  1978年   37491篇
  1977年   31972篇
  1976年   29652篇
  1975年   31693篇
  1974年   37323篇
  1973年   35571篇
  1972年   33270篇
  1971年   30665篇
  1970年   28571篇
  1969年   26930篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
51.
52.
Background: Traumatic brain injury (TBI) results in verbal recall deficits and impaired processing of emotion encoded in facial appearance, prosody and the linguistic content of messages. Emotion facilitates memory (emotional memory advantage) for non-brain injured (NBI) individuals but the impact of emotion on verbal recall for linguistically encoded stimuli in TBI has not been explored.

Aims: The purpose of this study was to determine the effects of stimulus emotional content on verbal recall of words and paragraphs in TBI compared to NBI individuals.

Methods and procedures: Six 10-item lists, each with five emotional and five neutral words, and six paragraphs (three emotional, three neutral) were counterbalanced and presented in random order to 20 individuals with TBI and 44 NBI. The number of words from lists and the number of content units from paragraphs were compared for the two groups.

Outcomes and results: The NBI participants recalled more words from the lists and content units from the paragraphs than the individuals with TBI. Both groups recalled significantly more emotional than neutral words. NBI but not TBI participants had significantly greater recall for information in paragraphs with emotional content.

Conclusions: Participants with TBI showed impaired recall of words and paragraph content. Emotion facilitated word and paragraph content recall for neurotypical individuals but emotional memory advantage was limited to words for the TBI participants.  相似文献   

53.
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   
54.
55.
Introduction: In men, lower urinary tract symptoms (LUTS) are primarily attributed to benign prostatic hyperplasia (BPH). Therapeutic options are targeted to relax prostate smooth muscle and/or reduce prostate enlargement.

Areas covered: This article reviews the major preclinical and clinical data on PDE5 inhibitors with a specific focus on tadalafil. It includes details of the role of the nitric oxide (NO)-cyclic guanosine monophosphate (cGMP) – PDE5 pathway in the LUT organs (bladder and prostate) in addition to the available data on tadalafil in patients with LUTS secondary to BPH with or without erectile dysfunction (ED).

Expert opinion: Preclinical and clinical data have clearly demonstrated that PDE5 inhibitors induce bladder and prostate relaxation, which contributes to the improvement seen in storage symptoms in both animal models of bladder and prostate hypercontractility. Tadalafil is effective both as a monotherapy and add-on therapy in patients with LUTS secondary to BPH. Furthermore, as LUTS-BPH and ED are urological disorders that commonly coexist in aging men, tadalafil is more advantageous than α1-adrenoceptors and should be used as the first option. Tadalafil is a safe and tolerable therapy and unlike α1- adrenoceptors and 5-alpha reductase inhibitors, which can cause sexual dysfunctions, tadalafil improves sexual function.  相似文献   

56.
57.
58.
59.
60.
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