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   1510241篇
  免费   106081篇
  国内免费   4088篇
耳鼻咽喉   21105篇
儿科学   48530篇
妇产科学   43810篇
基础医学   218947篇
口腔科学   42911篇
临床医学   125019篇
内科学   301209篇
皮肤病学   33028篇
神经病学   117213篇
特种医学   55664篇
外国民族医学   373篇
外科学   224172篇
综合类   33474篇
现状与发展   3篇
一般理论   344篇
预防医学   117746篇
眼科学   35348篇
药学   116977篇
  53篇
中国医学   5464篇
肿瘤学   79020篇
  2021年   13168篇
  2019年   13202篇
  2018年   19207篇
  2017年   14049篇
  2016年   14909篇
  2015年   17604篇
  2014年   23527篇
  2013年   34736篇
  2012年   49795篇
  2011年   52893篇
  2010年   30782篇
  2009年   27628篇
  2008年   48263篇
  2007年   51781篇
  2006年   51484篇
  2005年   50016篇
  2004年   47357篇
  2003年   45635篇
  2002年   44492篇
  2001年   63461篇
  2000年   65408篇
  1999年   55282篇
  1998年   15435篇
  1997年   13700篇
  1996年   13917篇
  1995年   13060篇
  1994年   12349篇
  1992年   43407篇
  1991年   42438篇
  1990年   41979篇
  1989年   40528篇
  1988年   37848篇
  1987年   36948篇
  1986年   35323篇
  1985年   33610篇
  1984年   25034篇
  1983年   21749篇
  1982年   12929篇
  1979年   23946篇
  1978年   16739篇
  1977年   14543篇
  1976年   13762篇
  1975年   15143篇
  1974年   17878篇
  1973年   17297篇
  1972年   16430篇
  1971年   15323篇
  1970年   14288篇
  1969年   13859篇
  1968年   13110篇
排序方式: 共有10000条查询结果,搜索用时 62 毫秒
11.
12.
We review the spectrum of cutaneous disorders associated with inflammatory and neoplastic plasmacytic pathology. Because plasma cells are derived from B‐lymphocytes our overview includes discussion of certain lymphoplasmacytic proliferations. It is structured along histopathological lines, addressing conditions characterized by (a) cutaneous plasma cell infiltrates, (b) deposits of plasma cell products or their derivatives in the skin and (c) miscellaneous, poorly understood cutaneous complications of plasmacytic disorders. Lesions arising primarily in the skin and those due to cutaneous involvement by multisystem disorders are addressed. The range includes a spectrum of tumefactive and circulatory manifestations. We highlight key clinical and pathological features of the different conditions and outline recent advances in our understanding of these entities. By emphasizing the dermatopathological characteristics of this spectrum of disorders we hope to hone the diagnostic accuracy of practitioners in the field.  相似文献   
13.
14.
15.
Breast pseudoaneurysms after a core needle biopsy are a rare complication with a low incidence. However, it is important to be aware of the possibility of complications that require treatment.  相似文献   
16.
17.
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   
18.
19.
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   

20.
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