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   2005627篇
  免费   155231篇
  国内免费   3037篇
耳鼻咽喉   27392篇
儿科学   66354篇
妇产科学   56604篇
基础医学   295075篇
口腔科学   58989篇
临床医学   176706篇
内科学   384877篇
皮肤病学   43642篇
神经病学   157502篇
特种医学   78964篇
外国民族医学   529篇
外科学   304366篇
综合类   46130篇
现状与发展   3篇
一般理论   647篇
预防医学   154958篇
眼科学   46392篇
药学   153055篇
  3篇
中国医学   3781篇
肿瘤学   107926篇
  2018年   18445篇
  2015年   18416篇
  2014年   25360篇
  2013年   38822篇
  2012年   52432篇
  2011年   56029篇
  2010年   32923篇
  2009年   31390篇
  2008年   53677篇
  2007年   56808篇
  2006年   57794篇
  2005年   55853篇
  2004年   55138篇
  2003年   52642篇
  2002年   51705篇
  2001年   93187篇
  2000年   96584篇
  1999年   81478篇
  1998年   21921篇
  1997年   19861篇
  1996年   20052篇
  1995年   19423篇
  1994年   18263篇
  1993年   17293篇
  1992年   66959篇
  1991年   66210篇
  1990年   65144篇
  1989年   62963篇
  1988年   58484篇
  1987年   57672篇
  1986年   54760篇
  1985年   52983篇
  1984年   39476篇
  1983年   33925篇
  1982年   19616篇
  1981年   17727篇
  1980年   16642篇
  1979年   37892篇
  1978年   26545篇
  1977年   22403篇
  1976年   21260篇
  1975年   22886篇
  1974年   27816篇
  1973年   26585篇
  1972年   24719篇
  1971年   23384篇
  1970年   21538篇
  1969年   20308篇
  1968年   18709篇
  1967年   16955篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
Cidofovir is an acyclic nucleoside phosphonate with broad-spectrum activity against DNA viruses, including human papilloma virus (HPV). However, data on the efficacy of cidofovir in an immunosuppressive setting remain contradictory. We report for the first time on the promotion of the healing of recalcitrant warts in a patient with myelodysplastic syndrome with intravenous cidofovir treatment.  相似文献   
92.
The incidence of asthma has been reported to be associated with obesity. An alternative analysis, of net change in prevalence, does not require exclusion of those with asthma at baseline. Follow-up data were obtained from 9,552 participants in the European Community Respiratory Health Survey and the Swiss cohort Study on Air Pollution and Lung Disease in Adults. Incidence of asthma was analysed by proportional hazards regression, and net changes in symptoms and asthma status by generalised estimating equations, by obesity group. Incidence and net change in ever having had asthma were greater in females than in males, and in participants who remained obese compared with those who were never obese (hazard ratio 2.00, 95% confidence interval 1.25-3.20; excess net change 2.8%, 0.4-5.3% per 10 yrs). The effect of being obese on net change in diagnosed asthma was greater in females than in males, but for net change in wheeze without a cold it was greater in males. The present results are consistent with asthma being more frequently diagnosed in females, especially obese females. These findings may help to explain the reports of a stronger association between asthma and obesity in females than in males.  相似文献   
93.
94.
95.
Atherosclerotic renal artery stenosis (ARAS) may cause hypertension, progressive renal failure, and recurrent pulmonary edema. It typically occurs in high risk patients with coexistent vascular disease elsewhere. Most patients with ARAS are likely to die from coronary heart disease or stroke before end-stage renal failure occurs. Recent controlled trials have shown that most patients undergoing angioplasty to treat renovascular hypertension still need antihypertensive agents 6 or 12 months after the procedure. Nevertheless, the number of antihypertensive agents required to control blood pressure adequately is lower following angioplasty than for medication alone. Trials assessing the value of revascularization for preserving renal function or preventing clinical events are only in the early recruitment phase. Revascularization should be undertaken in patients with ARAS and resistant hypertension or heart failure, and probably in those with rapidly deteriorating renal function or with an increase in plasma creatinine levels during angiotensin-converting enzyme inhibition. With or without revascularization, medical therapy using antihypertensive, hypolipidemic and antiplatelet agents is necessary in almost all cases.  相似文献   
96.
97.
98.
99.
A 19-item survey instrument was designed and mailed by the Infectious Diseases Society of America to its membership to determine the media preferred by infectious diseases physicians for continuing medical education on general topics and on antimicrobial resistance. The objective of the survey was to offer the developers of educational programs knowledge on which to base more-effective ways to deliver educational materials to physicians in this specialty.  相似文献   
100.
OBJECTIVE: To assess the effects of adding combined estradiol/norethisterone acetate therapy (CENT) to goserelin acetate treatment (GA) of dysfunctional uterine bleeding (DUB) in perimenopausal women. METHODS: In a randomized, placebo-controlled, double-blind trial followed by an open follow-up study, 31 perimenopausal women with DUB were recruited from gynecological outpatient departments of two Dutch hospitals and randomized for treatment with either GA/placebo or GA/CENT for 6 months followed by 18 months of GA/CENT for all. The main outcome measures were abdominal pain, number of bleeding days, double-layer endometrial thickness (DET), Greene climacteric score (GCS), visual analog scale for well-being, bone mineral density (BMD) and mammographic density (BI-RAD score). RESULTS: Abdominal pain, number of bleeding days and DET decreased in both groups, the between-group difference in decrease not being statistically significant. GCS initially showed significant improvement in the GA/CENT group. BMD decreased significantly in the GA/placebo group (-4.1%) compared with the GA/CENT group (-0.3%). Another 18 months of GA/CENT did not result in a lasting difference in BMD between groups. BI-RAD scores did not differ significantly between or within the two groups. CONCLUSIONS: Adding CENT to GA treatment for DUB in perimenopausal women initially prevented BMD loss and improved climacteric complaints, while having no negative impact on vaginal bleeding, abdominal pain or BI-RAD scores. However, prolonged treatment did not result in a lasting prevention of bone loss.  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