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   166585篇
  免费   31701篇
  国内免费   2507篇
耳鼻咽喉   5364篇
儿科学   5798篇
妇产科学   2708篇
基础医学   5409篇
口腔科学   1768篇
临床医学   28083篇
内科学   50292篇
皮肤病学   7929篇
神经病学   16678篇
特种医学   7337篇
外科学   42913篇
综合类   367篇
现状与发展   72篇
一般理论   4篇
预防医学   7792篇
眼科学   3603篇
药学   1824篇
中国医学   70篇
肿瘤学   12782篇
  2024年   691篇
  2023年   4902篇
  2022年   1409篇
  2021年   3463篇
  2020年   6269篇
  2019年   2532篇
  2018年   7763篇
  2017年   7660篇
  2016年   8837篇
  2015年   8814篇
  2014年   16070篇
  2013年   16309篇
  2012年   6630篇
  2011年   6713篇
  2010年   11049篇
  2009年   14830篇
  2008年   6819篇
  2007年   5053篇
  2006年   7440篇
  2005年   4718篇
  2004年   3832篇
  2003年   2774篇
  2002年   2775篇
  2001年   3916篇
  2000年   3100篇
  1999年   3361篇
  1998年   3838篇
  1997年   3613篇
  1996年   3499篇
  1995年   3310篇
  1994年   2051篇
  1993年   1630篇
  1992年   1418篇
  1991年   1456篇
  1990年   1088篇
  1989年   1209篇
  1988年   1056篇
  1987年   886篇
  1986年   908篇
  1985年   746篇
  1984年   574篇
  1983年   543篇
  1982年   551篇
  1981年   433篇
  1980年   401篇
  1979年   331篇
  1978年   356篇
  1977年   434篇
  1975年   296篇
  1972年   310篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
82.
This review discusses treatment options for men with premature ejaculation (PE), a common sexual dysfunction characterized by short ejaculatory latency, decreased sexual satisfaction, and distress. For a number of reasons, including embarrassment and the belief that PE is a normal part of aging, that it has no effective treatment, or that it will resolve itself, few men with PE seek treatment. Although several treatment options exist (eg, behavioral, cognitive, and sex therapy methods; desensitizing drugs; off-label use of antidepressants, phosphodiesterase type 5 inhibitors, or à-blockers), the majority of men with PE are not satisfied with their results. New pharmacologic drugs develped specifically for the treatment of PE are undergoing evaluation in clinical trials. For example, recent clinical research studies have revealed on-demand administration of one such drug, dapoxetine, which achieved significant improvements in ejaculatory latency, control over ejaculation, and satisfaction with sexual intercourse. In addition, partners of men who received dapoxetine likewise reported improved satisfaction with sexual intercourse. Future studies may reveal that integration of pharmacologic drugs with psychologic and/or behavioral therapy techniques may be the optimal approach to the management of PE. PE is a treatable condition, and new drugs in development may provide benefits over those available.  相似文献   
83.
84.
85.
Editorial     
  相似文献   
86.
87.
BACKGROUND: 1Alpha,25-dihydroxyvitamin D(3) [1,25(OH)(2) Vitamin D(3)] induces growth inhibition in squamous cell carcinoma (SCC) cell lines of the head and neck by arresting the cells in the G0/G1 phase of the cell cycle, probably due to an enhanced expression of p21, which could be demonstrated in other cell lines (JPPA, SCC9) before. In SCC25, a SCC cell line isolated from tongue, growth inhibition but no overexpression of p21 was detected. The retinoblastoma gene, as a direct target of G1 cyclin-CDK complexes, showed an obvious shift from the hyperphosphorylated to the hypophosphorylated form under 1,25(OH)(2)Vitamin D(3), which indicates that the growth inhibition takes place in the G0/G1 phase. To explore the possible pathway of growth inhibition in SCC25 we investigated other cell cycle inhibitors (p18, p19, p27). METHODS: Synchronized cells were treated with 1,25(OH)(2)Vitamin D(3) over 96 h. The cell cycle status and expression of cell cycle-regulating proteins was determined by fluorescence-activated cell sorting (FACS) and Western blotting. An overexpression of p18 in 1,25(OH)(2)Vitamin D(3) vs. ethanol-treated cells was determined until 30 h in SCC25. No influence was detectable on the expression of p27 and p19. CONCLUSION: One mechanism by which 1,25(OH)(2)Vitamin D(3) controls cell growth might be the upregulation of p21. As p21 was unsusceptible to 1,25(OH)(2)Vitamin D(3) in SCC25, other inhibiting proteins were necessary to be tested. The proven upregulation of p18 seems to be the responsible step for growth inhibition of 1,25(OH)(2)Vitamin D(3) in SCC25.  相似文献   
88.
Prostatitis and male infertility are frequent disorders, and the role of prostatitis in male infertility has been under discussion for more than 30 years. Many researchers have shown relevant links between the two. Although a causal relationship has not been definitely demonstrated, increasing evidence shows that chronic prostatitis has a relevant negative impact on male fertility potential, at least in certain subgroups. In the following review, we focus on the present state of knowledge on the role of chronic prostatitis as an etiologic factor in male infertility.  相似文献   
89.
Medical therapy is currently the most popular treatment choice for lower urinary tract symptoms (LUTS) associated with benign prostatic hyperplasia (BPH). Because medical therapy of BPH-related LUTS is considered a life-long strategy, short- and long-term cost considerations should play a major role in therapeutic decision-making. The effectiveness in terms of long and short amelioration of symptoms, flow rate, and quality of life are well documented for 5α-blockers and 5α-reductase inhibitors as well as for the gold standard treatment for BPH, transurethral resection of the prostate and minimally invasive therapies. Short-and long-term safety concerns also are well documented for these various treatment options. On the contrary, short- and long-term costs have been less well studied and comparisons depend on the model or analyses undertaken in the few studies available. However, the economic studies based on prospective clinical trial data that have become available throughout the past several decades allow us to rationalize our use of α-blockers, 5α -reductase inhibitors, and combination therapy, taking into consideration age, severity of symptoms, prostate volume, prostate-specific antigen, and the differential response of the various medications (and combination) in selected patients. Based on current studies, 5α -blockers generally provide cost-effective therapy for most patients, whereas 5α-reductase therapy and combination therapy provide cost-effective treatment for patients with larger prostate glands or higher baseline prostate-specific antigen levels.  相似文献   
90.
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