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   4502篇
  免费   312篇
  国内免费   23篇
耳鼻咽喉   45篇
儿科学   92篇
妇产科学   86篇
基础医学   618篇
口腔科学   40篇
临床医学   550篇
内科学   912篇
皮肤病学   65篇
神经病学   539篇
特种医学   145篇
外国民族医学   2篇
外科学   780篇
综合类   39篇
一般理论   1篇
预防医学   258篇
眼科学   31篇
药学   385篇
中国医学   6篇
肿瘤学   243篇
  2023年   26篇
  2022年   54篇
  2021年   130篇
  2020年   88篇
  2019年   117篇
  2018年   141篇
  2017年   112篇
  2016年   127篇
  2015年   126篇
  2014年   164篇
  2013年   223篇
  2012年   341篇
  2011年   333篇
  2010年   199篇
  2009年   159篇
  2008年   247篇
  2007年   267篇
  2006年   222篇
  2005年   236篇
  2004年   217篇
  2003年   196篇
  2002年   189篇
  2001年   79篇
  2000年   75篇
  1999年   64篇
  1998年   44篇
  1997年   23篇
  1996年   31篇
  1995年   17篇
  1994年   21篇
  1993年   19篇
  1992年   38篇
  1991年   31篇
  1990年   41篇
  1989年   41篇
  1988年   36篇
  1987年   45篇
  1986年   32篇
  1985年   37篇
  1984年   33篇
  1983年   17篇
  1982年   13篇
  1979年   25篇
  1978年   11篇
  1974年   19篇
  1973年   15篇
  1971年   11篇
  1970年   15篇
  1969年   9篇
  1966年   8篇
排序方式: 共有4837条查询结果,搜索用时 15 毫秒
31.
32.
33.
34.
Benoit RM  Naslund MJ  Cohen JK 《Urology》2000,56(1):116-120
OBJECTIVES: Radical prostatectomy is the standard of care for the treatment of clinically localized prostate cancer in the appropriate patient. However, the morbidity associated with this procedure remains controversial, since complications from centers of excellence are low but nationwide surveys have reported a much higher risk of complications. This study reports the complication rates after radical retropubic prostatectomy (RRP) for men in the Medicare population. METHODS: All men in the Medicare population who underwent RRP in 1991 were identified. All inpatient, outpatient, and physician (Part B) Medicare claims for these men for 1991 to 1993 were then analyzed to determine outcomes. Procedures performed for complications resulting from RRP were recorded, as were the diagnosis codes that may have heralded a complication after RRP. RESULTS: In 1991, 25,651 men in the Medicare population underwent RRP. The mean age of these men was 70.5 years. Procedures for the relief of bladder outlet obstruction or urethral strictures after RRP occurred in 19.5% of these men. A penile prosthesis was implanted in 718 men (2.8%) after prostatectomy, and 593 men (2.3%) had an artificial urinary sphincter placed after prostatectomy. A diagnosis of urinary incontinence was reported in 5573 men (21.7%) after radical prostatectomy, but only 2025 of these men (7.9%) continued to carry this diagnosis more than 1 year after prostatectomy. A diagnosis of erectile dysfunction was reported in 5510 men (21.5%) after radical prostatectomy, but only 3276 of these men (12.8%) continued to carry this diagnosis more than 1 year after surgery. CONCLUSIONS: A review of a large, nationwide, heterogenous cohort of men revealed a morbidity rate that is slightly higher than that reported by major centers that perform large numbers of radical retropubic prostatectomies but is lower than complication rates obtained by patient surveys. The limitations of claim information in determining patient outcomes, however, must be considered when evaluating these data.  相似文献   
35.
36.
We report a 3-year, 5-month-old boy with an adrenocortical carcinoma. These tumours are rare and highly malignant in childhood. In most cases they are functional, secreting adrenocortical hormones. In this case there was a misleading coexistence with a second abdominal neoplasm, which was a ganglioneuroma; this is a rare benign tumour arising from the sympathetic nervous system. The imaging investigations and their findings are discussed and correlated with pathology. Received: 15 January 1997 Accepted: 15 October 1997  相似文献   
37.
Laurent Coudeville  MD  PhD    Alain Brunot  MD  PhD    Thomas D. Szucs  MD  MBA  MPH    Benoit Dervaux  PhD 《Value in health》2005,8(3):209-222
OBJECTIVE: To determine the economic impact of childhood varicella vaccination in France and Germany. METHODS: A common methodology based on the use of a varicella transmission model was used for the two countries. Cost data (2002 per thousand) were derived from two previous studies. The analysis focused on a routine vaccination program for which three different coverage rates (CRs) were considered (90%, 70%, and 45%). Catch-up strategies were also analyzed. A societal perspective including both direct and indirect costs and a third-party payer perspective were considered (Social Security in France and Sickness Funds in Germany). RESULTS: A routine vaccination program has a clear positive impact on varicella-related morbidity in both countries. With a 90% CR, the number of varicella-related deaths was reduced by 87% in Germany and by 84% in France. In addition, with a CR of 90%, routine varicella vaccination induces savings in both countries from both societal (Germany 61%, France 60%) and third-party payer perspectives (Germany 51%, France 6.7%). For lower CRs, routine vaccination remains cost saving from a third-party payer perspective in Germany but not in France, where it is nevertheless cost-effective (cost per life-year gained of 6521 per thousand in the base case with a 45% CR). CONCLUSION: Considering the impact of vaccination on varicella morbidity and costs, a routine varicella vaccination program appears to be cost saving in Germany and France from both a societal and a third-party payer perspective. For France, routine varicella vaccination remains cost-effective in worst cases when a third-party payer perspective is adopted. Catch-up programs provide additional savings.  相似文献   
38.
39.
There have been conflicting reports as to whether olanzapine produces lower occupancy of striatal dopamine D(2)/D(3) receptor than typical antipsychotic drugs and preferential occupancy of extrastriatal dopamine D(2)/D(3) receptors. We performed [(18)F] fallypride PET studies in six schizophrenic subjects treated with olanzapine and six schizophrenic subjects treated with haloperidol to examine the occupancy of striatal and extrastriatal dopamine receptors by these antipsychotic drugs. [(18)F] setoperone PET studies were performed in seven olanzapine-treated subjects to determine 5-HT(2A) receptor occupancy. Occupancy of dopamine D(2)/D(3) receptors by olanzapine was not significantly different from that seen with haloperidol in the putamen, ventral striatum, medial thalamus, amygdala, or temporal cortex, that is, 67.5-78.2% occupancy; olanzapine produced no preferential occupancy of dopamine D(2)/D(3) receptors in the ventral striatum, medial thalamus, amygdala, or temporal cortex. There was, however, significantly lower occupancy of substantia nigra/VTA dopamine D(2)/D(3) receptors in olanzapine-treated compared to haloperidol-treated subjects, that is, 40.2 vs 59.3% (p=0.0014, corrected for multiple comparisons); in olanzapine-treated subjects, the substantia nigra/VTA was the only region with significantly lower dopamine D(2)/D(3) receptor occupancy than the putamen, that is, 40.2 vs 69.2% (p<0.001, corrected for multiple comparison). Occupancy of 5-HT(2A) receptors was 85-93% in the olanzapine- treated subjects. The results of this study demonstrated that olanzapine does not produce preferential occupancy of extrastriatal dopamine D(2)/D(3) receptors but does spare substantia nigra/VTA receptors. Sparing of substantia nigra/VTA dopamine D(2)/D(3) receptor occupancy may contribute to the low incidence of extrapyramidal side effects in olanzapine-treated patients.  相似文献   
40.
PURPOSE: Incapacitating symptom burden in cancer patients contributes to poor quality of life (QOL) and can influence treatment outcomes because of poor tolerance to therapy. In this study, the role of circulating cytokines in the production symptoms in cancer patients is evaluated. EXPERIMENTAL DESIGN: Eighty patients with metastatic colorectal cancer with either normal (group I, n = 40) or dampened (group II, n = 40) 24-hour rest/activity patterns measured by actigraphy were identified. Actigraphy patterns were correlated with QOL indices, serum cortisol obtained at 8:00 a.m. and 4:00 p.m. and with serum levels of transforming growth factor-alpha, tumor necrosis factor-alpha, and interleukin 6 (IL-6) obtained at 8:00 a.m. and analyzed in duplicate by ELISA. Cytokine levels and survival were also correlated. RESULTS: Group II patients had significantly higher pre treatment levels of all three cytokines, displayed significantly poorer emotional and social functioning, had higher fatigue, more appetite loss, and poorer performance status compared with group I patients. Transforming growth factor-alpha (TGF-alpha) and IL-6 were significantly increased in the patients with WHO performance status >1 and in those with appetite loss. Fatigue was significantly associated with elevated TGF-alpha only. IL-6 was increased in those patients with extensive liver involvement and multiple organ replacement, and it was significantly correlated with dampened cortisol rhythm. In a multivariate analysis, IL-6 was correlated with poor treatment outcome. CONCLUSIONS: Significant correlations were found between serum levels of TGF-alpha and IL-6, circadian patterns in wrist activity and serum cortisol and tumor-related symptoms in patients with metastatic colorectal cancer. These data support the hypothesis that some cancer patient's symptoms of fatigue, poor QOL, and treatment outcome are related to tumor or host generated cytokines and could reflect cytokine effects on the circadian timing system. This interplay between cytokine signaling pathways, the hypothalamic-pituitary-adrenal axis, the autonomic nervous system, and efferent pathways of the suprachiasmatic nucleus that control circadian physiology, opens the way to new rational interventions for symptom management in cancer patients.  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