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   3173篇
  免费   297篇
  国内免费   23篇
耳鼻咽喉   4篇
儿科学   172篇
妇产科学   29篇
基础医学   447篇
口腔科学   113篇
临床医学   292篇
内科学   659篇
皮肤病学   65篇
神经病学   254篇
特种医学   493篇
外科学   310篇
综合类   60篇
预防医学   197篇
眼科学   22篇
药学   142篇
中国医学   4篇
肿瘤学   230篇
  2022年   17篇
  2021年   26篇
  2020年   18篇
  2019年   23篇
  2018年   43篇
  2017年   46篇
  2016年   45篇
  2015年   56篇
  2014年   62篇
  2013年   108篇
  2012年   84篇
  2011年   99篇
  2010年   109篇
  2009年   106篇
  2008年   116篇
  2007年   92篇
  2006年   118篇
  2005年   97篇
  2004年   77篇
  2003年   66篇
  2002年   89篇
  2001年   56篇
  2000年   66篇
  1999年   89篇
  1998年   155篇
  1997年   146篇
  1996年   140篇
  1995年   107篇
  1994年   95篇
  1993年   92篇
  1992年   60篇
  1991年   43篇
  1990年   50篇
  1989年   93篇
  1988年   78篇
  1987年   84篇
  1986年   66篇
  1985年   80篇
  1984年   41篇
  1983年   47篇
  1982年   49篇
  1981年   25篇
  1980年   47篇
  1979年   26篇
  1978年   35篇
  1977年   23篇
  1976年   32篇
  1975年   41篇
  1973年   16篇
  1972年   18篇
排序方式: 共有3493条查询结果,搜索用时 15 毫秒
1.
Functional recovery, the goal of treatment, has long been overlooked in the assessment of effectiveness of pharmacological treatments. However, with the recent shift in paradigm, from syndromal–symptomatic recovery to functional recovery, there appears to be a new interest in the definition and evaluation of functional recovery. Since functional recovery lags symptomatic recovery, sometimes by months or years, the attainment of functional recovery will be determined by both efficacy and long-term compliance. Quetiapine, due to its efficacy in both mania and depression, and effect on cognition may lead to improved functioning in patients with bipolar disorder.  相似文献   
2.
BACKGROUND: Our aims in the present study were to estimate the influences of pain and urinary symptoms on quality of life, and to determine which of these two variables has the most predictive power with respect to quality of life in young men with chronic prostatitis-like symptoms. METHODS: Chronic prostatitis-like symptoms were measured by the National Institutes of Health-Chronic Prostatitis Symptom Index. Of the 28,841 men aged 20 years who lived in the study community, 18,495 men (a response rate 64.1%) agreed to participate in the study. A total of 1057 men who complained of symptoms indicative of chronic prostatitis were included in the study. The influences of pain and urinary symptoms on quality of life were determined using logistic regression analysis. The receiver operating characteristic (ROC) curve was used to estimate the predictive ability of each of these variables with respect to quality of life. RESULTS: Results from multivariate analysis showed that both pain and urinary symptoms were associated with an increased likelihood of impaired quality of life, although pain contributed more to a reduced quality of life than urinary symptoms. Relative to men who experienced mild pain, men who experienced moderate pain had a 3.9-fold risk of poor quality of life (odds ratio [OR], 3.87; 95% confidence interval [CI], 2.86-5.23; P < 0.001) and those who experienced severe pain had a 15.7-fold risk of reduced quality of life (OR, 15.68; 95% CI, 6.59-37.35; P < 0.001). Moderate urinary symptoms were associated with a 1.4-fold risk of bother (OR, 1.41; 95% CI, 1.01-1.99; P < 0.001) and severe urinary symptoms were associated with 2.4-fold risk (OR, 2.39; 95% CI, 1.37-4.12; P < 0.001), relative to mild urinary symptoms. Comparison of the effects of pain and urinary symptoms showed that pain severity had the most predictive power for bother, quality of life, and quality-of-life impact. The areas under the ROC curves for bother, quality of life, and quality-of-life impact were 71.3%, 69.3% and 72.5%, respectively. CONCLUSION: Urinary symptoms and pain might be associated with an increased likelihood of impaired quality of life in young men with chronic prostatitis-like symptoms. In addition, our findings suggest that pain severity is the most influential variable for determining quality of life in this population.  相似文献   
3.
4.
Introduction: Suramin is a synthetic polysulfonated naphthylurea which has been used for the treatment of African trypanosomiasis and onchocerciasis, but since the mid-1980s has received attention as a possible antiretroviral and antineoplastic agent. Objective: This clinical trial of suramin was undertaken as a phase I/II study in patients with hormone-refractory prostate cancer, with the hypothesis that the intensity of therapy with suramin could be increased significantly if measures were undertaken to maintain the plasma concentrations of the drug under 300 μg/ml. Methods: We report the clinical results of this trial, wherein patients were treated at three different targeted plasma suramin concentrations (275, 215 and 175 μg/ml) for varying periods of time (2, 4 or 8 weeks), with delivery of the drug by continuous intravenous infusion. Results: The major toxicity observed in this trial was neurologic, consisting of a motor and sensory peripheral neuropathy that resulted in both paresis and paralysis of the limbs. Nearly all of this severe (CTEP grade III, IV) neurologic toxicity was observed in the patients treated at a plasma suramin concentration of 275 μg/ml for 4 or more weeks. A single patient treated at 215 μg/ml for 8 weeks developed moderate (CTEP grade III) proximal lower extremity weakness, and no patient treated at 175 μg/ml developed this toxicity. The second most common toxicity observed was infection of the central venous catheter. The overall response rate for all of the evaluable patients was 17% (13 of 75 patients). In addition, prostate-specific antigen (PSA)-defined responses were observed in six patients receiving therapy at 175 μg/ml, but these responses were confounded by cessation of therapy with flutamide during suramin treatment. Conclusions: In summary, although plasma suramin concentrations were maintained below 300 μg/ml, neurologic toxicity nonetheless occurred with high frequency in patients treated at 275 μg/ml for 4 or more weeks. Therapy at 215 and 175 μg/ml was in general well tolerated, but central venous catheter-related infection, as well as the inconvenience and expense of continuous infusional therapy, make this method of drug delivery impractical. Only moderate antitumor activity was observed during this trial, but it is possible that both continuation of flutamide and flutamide withdrawal during suramin therapy confounded the assessment of suramin’s activity in hormone-refractory prostate cancer. Received: 9 June 1995/Accepted: 18 March 1996  相似文献   
5.
6.
Aims Cardiovascular disease (CVD) is a major complication of Type 2 diabetes mellitus. The renin‐angiotensin system (RAS) and nitric oxide production are both important regulators of vascular function and blood pressure. Genes encoding proteins involved in these pathways are candidates for a contribution to CVD in diabetic patients. We have investigated variants of the angiotensinogen (AGT), angiotensin converting enzyme (ACE), angiotensin type 1 receptor (AT1R) and endothelial nitric oxide synthase (NOS3) genes for association with subclinical measures of CVD in families with Type 2 diabetes mellitus (T2DM). Methods Atherosclerosis was measured by carotid intima‐media thickness and calcification of the carotid and coronary arteries in 620 European Americans and 117 African Americans in the Diabetes Heart Study. Because of the role of these systems in blood pressure regulation, blood pressure was also investigated. Results Compelling evidence of association was not detected with any of the SNPs with any outcome measures after adjustments for covariates despite sufficient power to detect relatively small differences in traits for specific genotype combinations. Conclusions Genetic variation of the RAS and NOS3 genes do not appear to strongly influence subclinical cardiovascular disease or blood pressure in this diabetic population.  相似文献   
7.
Numerous investigators have reported the safety, cost effectiveness, and low morbidity and mortality of percutaneous endoscopic gastrostomy (PEG) but not studies compare the results of gastroenterologists and surgeons performing PEG. In a retrospective review of PEG performed at our institution, morbidity and mortality were compared between these two groups. The procedure was performed by either the surgical service (n = 49) or gastroenterology service (n = 51). One hundred PEGs were successfully placed in 92 patients. Three placement failures occurred in the gastroenterology group. Major complications were defined as conditions requiring operative intervention or resulting in death. Minor complications, using a defined list (13 different complications), were those not serious or life-threatening, which were managed medically or resolved without treatment. Twenty-nine minor (17 patients) complications and 3 major (3 patients) complications occurred in the gastroenterology group. Thirteen minor (11 patients) complications and 4 major (4 patients) complications occurred in the surgery group. Overall 30-day mortality was 14 per cent (13 patients), two of which were probably procedure-related in the gastroenterology group. In both groups, there was no difference in the numbers of patients who had complications (P greater than 0.05). The complication rate (numbers of complications/number of patients) doubled in the gastroenterology group compared with the surgery group for minor (P less than 0.04) and total complications (minor and major--P less than 0.06). Since PEG is a procedure frequently performed by gastroenterologists, it is imperative that surgeons, particularly those not performing endoscopy, be aware of the potential morbidity associated with PEG.  相似文献   
8.
Evaluation of an on-line patient exposure meter in neuroradiology   总被引:1,自引:0,他引:1  
  相似文献   
9.
Pediatric knee MR imaging: pattern of injuries in the immature skeleton   总被引:3,自引:0,他引:3  
  相似文献   
10.
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