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   5155篇
  免费   547篇
  国内免费   96篇
耳鼻咽喉   224篇
儿科学   251篇
妇产科学   424篇
基础医学   756篇
口腔科学   225篇
临床医学   301篇
内科学   452篇
皮肤病学   80篇
神经病学   258篇
特种医学   100篇
外国民族医学   4篇
外科学   714篇
综合类   643篇
现状与发展   1篇
预防医学   232篇
眼科学   172篇
药学   232篇
  3篇
中国医学   246篇
肿瘤学   480篇
  2024年   6篇
  2023年   85篇
  2022年   117篇
  2021年   226篇
  2020年   242篇
  2019年   230篇
  2018年   183篇
  2017年   238篇
  2016年   254篇
  2015年   229篇
  2014年   340篇
  2013年   362篇
  2012年   285篇
  2011年   257篇
  2010年   228篇
  2009年   224篇
  2008年   247篇
  2007年   242篇
  2006年   234篇
  2005年   200篇
  2004年   148篇
  2003年   150篇
  2002年   115篇
  2001年   123篇
  2000年   91篇
  1999年   80篇
  1998年   88篇
  1997年   56篇
  1996年   71篇
  1995年   64篇
  1994年   41篇
  1993年   35篇
  1992年   39篇
  1991年   40篇
  1990年   20篇
  1989年   23篇
  1988年   17篇
  1987年   15篇
  1986年   9篇
  1985年   23篇
  1984年   23篇
  1983年   19篇
  1982年   25篇
  1981年   16篇
  1980年   9篇
  1979年   6篇
  1978年   8篇
  1977年   4篇
  1976年   5篇
  1971年   2篇
排序方式: 共有5798条查询结果,搜索用时 546 毫秒
1.
2.
《Surgery (Oxford)》2020,38(4):197-203
Many women will experience one or more urinary tract infection (UTI) during their life. The most unfortunate will have many. Men presenting with infections, and women with recurrent episodes, require further investigation. A diagnosis of a UTI is often based on a typical spectrum of symptoms, with confirmatory urine cultures lagging a few days behind. Unfortunately, symptoms of a UTI may not be typical, and other conditions can manifest similarly. Treatment of UTI with antibiotics is usually required, but there is increasing awareness of the need for antimicrobial stewardship to avoid the misuse and overuse of antibiotics, even as patients are increasingly reluctant to take them. Recurrent UTI can cause significant morbidity and disruption to daily activities yet investigations rarely demonstrate a reversible cause. There are a host of different antibiotic and non-antibiotic interventions that aim to lower the risk of further infections. However, these are not reliably effective, bring side effects of their own and are often proposed to this desperate population of patients on the back of weak evidence of efficacy.  相似文献   
3.
4.
Helicobacter pylori is an established cause of gastric ulcers. Its role in causing recurrent aphthous stomatitis (RAS) remains controversial. Fifty-two RAS patients and 52 sex-matched controls were recruited in this case–control study. All subjects were screened for hematinic deficiencies and H. pylori. The latter was assessed quantitatively using the 14C-urea breath test. The χ2 test and Wilcoxon signed ranks test were used to compare H. pylori and hematinic indices between cases and controls, while conditional logistic regression was used to assess the associations between the occurrence of RAS and independent factors. H. pylori was positive in 56.7% of the overall sample, with no difference between RAS patients (50.8%) and controls (49.2%) (P = 0.843). The median H. pylori and haematological indices values did not show any association with ulcer diameter, number, or frequency. Interestingly, gastric hyperacidity was significantly associated with RAS, and this association was independent from tobacco smoking, alcohol drinking, and H. pylori (odds ratio 14.99, 95% confidence interval 2.47–90.95; P = 0.003). This study found no association between H. pylori and RAS. The association between RAS and gastric hyperacidity suggests that gastric refluxate, not H. pylori, has an effect on the oral mucosa that favours an ulcerative change.  相似文献   
5.
Marginal rate-based analyses are widely used for the analysis of recurrent events in clinical trials. In many areas of application, the events are not instantaneous but rather signal the onset of a symptomatic episode representing a recurrent infection, respiratory exacerbation, or bout of acute depression. In rate-based analyses, it is unclear how to best handle the time during which individuals are experiencing symptoms and hence are not at risk. We derive the limiting value of the Nelson-Aalen estimator and estimators of the regression coefficients under a semiparametric rate-based model in terms of an underlying two-state process. We investigate the impact of the distribution of the episode durations, heterogeneity, and dependence on the asymptotic and finite sample properties of standard estimators. We also consider the impact of these features on power in trials designed to test intervention effects on rate functions. An application to a trial of individuals with herpes simplex virus is given for illustration.  相似文献   
6.
7.
8.
9.
10.
Conclusion: Recurrent respiratory papillomatosis (RRP) patients with high surgical treatment frequency (≥ 1/year, HF) were significantly younger and had a more widespread laryngeal disease compared to a low frequency treated group (< 1 treatment/year, LF). This study confirms the existence of a clinical RRP group, not primarily related to HPV sub-type, but more care-intensive and in need of more vigilant follow-up. Objectives: RRP is associated with high morbidity due to its influence on breathing and voice. The purpose of this study was to characterize RRP patients in northern Sweden and investigate possible predictor factors affecting therapeutic needs. Method: Patients from the regional referral area (northern Sweden) were categorized for age, disease duration, juvenile or adult onset, profile of disease development, number of surgical sessions in relation to disease duration, laryngeal deposition of papilloma, gender, and HPV sub-types, in order to identify patients with increased need for frequent surgical treatment. Results: The median age of the RRP patients (n = 48) was 44.5 years; 34 (71%) were males and 14 (29%) females, most were infected with HPV 6. Patients with high surgical treatment frequency/year were significantly younger and showed more widespread papillomatous vegetation in the larynx, compared to the low frequency treated group.  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