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   834篇
  免费   37篇
  国内免费   5篇
耳鼻咽喉   2篇
儿科学   34篇
妇产科学   8篇
基础医学   80篇
口腔科学   80篇
临床医学   42篇
内科学   179篇
皮肤病学   54篇
神经病学   34篇
特种医学   16篇
外科学   187篇
预防医学   57篇
眼科学   24篇
药学   49篇
中国医学   4篇
肿瘤学   26篇
  2024年   1篇
  2023年   1篇
  2022年   15篇
  2021年   20篇
  2020年   16篇
  2019年   27篇
  2018年   31篇
  2017年   20篇
  2016年   14篇
  2015年   20篇
  2014年   32篇
  2013年   37篇
  2012年   60篇
  2011年   66篇
  2010年   41篇
  2009年   38篇
  2008年   60篇
  2007年   73篇
  2006年   49篇
  2005年   53篇
  2004年   59篇
  2003年   25篇
  2002年   18篇
  2001年   18篇
  2000年   10篇
  1999年   17篇
  1998年   5篇
  1997年   2篇
  1996年   5篇
  1995年   5篇
  1994年   5篇
  1993年   2篇
  1992年   8篇
  1991年   3篇
  1990年   6篇
  1989年   6篇
  1986年   1篇
  1985年   1篇
  1984年   1篇
  1983年   1篇
  1971年   1篇
  1969年   1篇
  1968年   1篇
  1966年   1篇
排序方式: 共有876条查询结果,搜索用时 15 毫秒
101.
OBJECTIVE: After non-response to the initial course of therapy, retreatment with alpha-interferon is not effective. The aim of this study was to ascertain whether the administration of N-acetyl cysteine and vitamin E could increase the response rate to retreatment with alpha-interferon. DESIGN: Prospective, multicentre clinical trial. SETTING: Twelve hospitals in Lombardy, Italy. PARTICIPANTS: 120 consecutive patients affected by biopsy-proven chronic hepatitis C who had been non-responders to a previous course of alpha-interferon, administered at the dosage of 3-6 million units (MU) three times a week (tiw) for 6 months. INTERVENTIONS: The patients were randomly assigned to one of two groups of treatment: group A, natural interferon-alphaN3, 6 or 9 MU tiw, when the body weight was < 60 kg or > or = 60 kg, respectively; group B, the same dosage of natural interferon-alphaN3 in association with oral administration of N-acetyl cysteine 1200 mg/day and vitamin E 600 mg/day. The period of treatment was 6 months in both groups. RESULTS: Neither end-therapy biochemical response nor sustained biochemical response rates were improved by the combination treatment, and in no case was clearance of the virus from serum observed. CONCLUSIONS: In this randomized study carried out on 120 patients with chronic hepatitis C not responsive to alpha-interferon, oral supplementation with N-acetyl cysteine and vitamin E did not improve the poor efficacy of retreatment with alpha-interferon alone.  相似文献   
102.
103.

Background

Warm ischemia time (WIT) and complication rates are two important parameters for evaluating the perioperative results of robot-assisted partial nephrectomy (RAPN). Few data are available about the clinical predictors of WIT and overall complications.

Objective

To identify clinical predictors of WIT and perioperative complications.

Design, setting, and participants

This is a retrospective study including 347 patients who underwent RAPN for suspicious renal cell carcinoma (RCC) at four referral centers from September 2008 to September 2010.

Intervention

All patients underwent RAPN using the da Vinci S Surgical System with hilar clamping.

Measurements

WIT >20 min and overall complication rates were the main outcomes. Postoperative complications were classified according to the Clavien/Dindo system. Moreover, the following perioperative variables were considered: clinical tumor size, anatomical tumor characteristics according to Preoperative Aspects and Dimensions Used for an Anatomical (PADUA) classification score, surgeon experience, console time, blood loss, and upper collecting system (UCS) repair.

Results and limitations

WIT >20 min was reported in 125 (36%) cases. Intraoperative and postoperative complications were observed in 10 (2.9%) and 41 (11.8%) cases, respectively. Surgeon experience (odds ratio [OR]: 6.381; 95% confidence interval [CI], 3.687-11.042; p < 0.001), clinical tumor size (OR: 1.022; 95% CI, 1.002-1.044; p = 0.03), the other anatomic characteristics determined by the PADUA classification score (OR: 1.294; 95% CI, 1.080-1.549; p = 0.005), and the UCS repair (OR: 2.987; 95% CI, 1.728-5.165; p < 0.001) turned out to be independent predictors of WIT >20 min. Similarly, surgeon experience (OR: 3.937; 95% CI, 2.011-7.705; p < 0.001), clinical tumor size (OR: 1.033; 95% CI, 1.009-1.058; p = 0.007), and the other anatomical characteristics determined by the PADUA classification score (OR: 1.427; 95% CI, 1.149-1.773; p < 0.001) turned out to be independent predictors of overall complication rates. The retrospective design is the main limitation of this multicenter, international study. Therefore, some patient characteristics and comorbidities were not recorded.

Conclusions

Anatomic tumor characteristics as determined by the PADUA classification score were independent predictors of WIT and overall complications, once adjusted for the effects of surgeon experience and clinical tumor size.  相似文献   
104.

Background

In postmenopausal women, the presence of risk factors for coronary artery disease (CAD) increases. However, the difference in prevalence of ischemia between pre- and postmenopausal women with multiple risk factors for CAD has not been well established.

Objectives

To compare the prevalence of ischemia on Tc99m-sestamibi myocardial perfusion scintigraphy (MPS) in pre-and postmenopausal women, and to evaluate whether menopause can be considered an independent risk predictor of ischemia in women with multiple risk factors for CAD.

Methods

This study retrospectively assessed 500 MPS of pre- and postmenopausal women with multiple risk factors for CAD. Statistical analysis was performed by using Fisher exact test and univariate and multivariate analysis, a p value ≤ 0.05 being considered significant.

Results

Postmenopausal women represented 55.9% of the sample; 83.3% were hypertensive; 28.9%, diabetic; 32.1%, smokers; 25%, obese; 61.2% had high cholesterol levels; and 34.3% had known CAD. Postmenopausal women were more often hypertensive, diabetic and dyslipidemic, and had lower functional capacity on exercise testing (p = < 0.005). The presence of ischemia on MPS did not significantly differ between the pre- and postmenopausal groups (p = 0.395). The only variable associated with ischemia on MPS was known CAD (p = 0.004).

Conclusion

The results suggest that, in women with multiple risk factors for CAD, menopause was not an independent predictor of ischemia on MPS. Those data support the idea that the investigation of ischemia via MPS in women with multiple risk factors for CAD should begin prior to menopause.  相似文献   
105.
Cirrhosis: diagnosis with sonographic study of the liver surface   总被引:9,自引:0,他引:9  
To find an objective sonographic sign of cirrhosis, the authors used a small-parts probe to examine the liver surface for irregularities that corresponded to those of nodular regeneration. Fifty healthy subjects were examined to assess the pattern of a sonographically normal-appearing liver surface. A second group of 75 patients, mainly with suspected diffuse chronic liver disease, was examined with particular attention to the most commonly described sonographic signs of cirrhosis, and laparoscopy and biopsy were also performed. The liver surface was examined in a third group of 225 patients with cancer in whom metastases had been demonstrated sonographically. A diagnosis of cirrhosis was made with sonography when surface irregularities were observed that were comparable to the anatomic abnormalities of a cirrhotic liver surface. An examination of the liver surface gave the best diagnostic rate for cirrhosis (88%). There were seven false-negative results, but in five of them no surface nodularity could be seen at laparoscopy, and the diagnosis was made only on the basis of histologic studies; there was one false-positive result. This study indicated that ultrasonography might be a reliable method to follow up patients with chronic liver disease that may progress to cirrhosis.  相似文献   
106.
Reports of Visceral larva migrans (VLM) are not frequent in Brazil, but the prevalence of this disease may be more common due to poor environmental conditions to which most of the children are exposed. The most common infectious agent is Toxocara canis, a parasite of the intestinal tract of dogs. Children get infected eating contaminated material with feces of dogs. The ova are swallowed and reach the intestinal lumen of the children. Systemic migration occurs by lymphatic or portal circulation to several organs, most frequently, to the liver and lungs, causing hepatosplenomegaly and/or bronchospasm.  相似文献   
107.
108.
109.
110.
Since April 2003, all adults requiring social care services must have an assessment to determine their eligibility, which is set within the four-level framework of Fair Access to Care Services [FACS; LAC (2002)13]. This paper examines the implementation of FACS by community mental health teams in eight sites in mental health partnership trusts, and one in a mental health and social care trust in the UK. Twenty-eight respondents (managers within trusts and social services departments) participated in in-depth qualitative interviews, which were undertaken between August 2004 and February 2005. The interviews covered: consultation with users and partner organisations; training and briefings for staff; FACS thresholds; integration of FACS and the Care Programme Approach; and the impact of implementing FACS on budgetary arrangements between health and social care. Using the framework analysis approach to analyse data, it was found that FACS implementation in mental health services has been somewhat haphazard, and has identified real differences between health and social care approaches to eligibility determination, assessment and priorities. In particular, the type and amount of consultation, training and induction into FACS was variable, and in some cases, unacceptably poor. While FACS may have reduced variability between authorities, the exercise of professional judgement in the operation of FACS and the lack of high-quality preventative services remain as potential sources of inequity within the system. The authors conclude that FACS has revealed and reinforced a growing separation rather than an integration of mental health and social care ideas and practices, at least in the participating sites.  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