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   4261篇
  免费   245篇
  国内免费   10篇
耳鼻咽喉   72篇
儿科学   398篇
妇产科学   109篇
基础医学   432篇
口腔科学   64篇
临床医学   224篇
内科学   899篇
皮肤病学   129篇
神经病学   569篇
特种医学   125篇
外科学   441篇
综合类   131篇
预防医学   186篇
眼科学   73篇
药学   203篇
中国医学   10篇
肿瘤学   451篇
  2023年   33篇
  2022年   56篇
  2021年   119篇
  2020年   60篇
  2019年   92篇
  2018年   112篇
  2017年   77篇
  2016年   100篇
  2015年   75篇
  2014年   140篇
  2013年   166篇
  2012年   239篇
  2011年   228篇
  2010年   141篇
  2009年   129篇
  2008年   208篇
  2007年   181篇
  2006年   176篇
  2005年   198篇
  2004年   184篇
  2003年   155篇
  2002年   133篇
  2001年   86篇
  2000年   125篇
  1999年   109篇
  1998年   46篇
  1997年   29篇
  1996年   31篇
  1995年   32篇
  1994年   24篇
  1993年   18篇
  1992年   72篇
  1991年   48篇
  1990年   55篇
  1989年   87篇
  1988年   65篇
  1987年   70篇
  1986年   64篇
  1985年   60篇
  1984年   65篇
  1983年   47篇
  1981年   22篇
  1979年   29篇
  1978年   20篇
  1977年   24篇
  1975年   22篇
  1974年   24篇
  1972年   25篇
  1970年   23篇
  1969年   26篇
排序方式: 共有4516条查询结果,搜索用时 15 毫秒
1.
2.
Determining aortic stenosis (AS) severity is clinically important. Calculating aortic valve (AV) area by means of the continuity equation assumes a circular left ventricular outflow tract (LVOT). The full impact of this assumption in calculating AV area is unknown. Predictors of noncircular LVOT shape in patients with AS are undefined.In 109 adult patients with AS who underwent multiplanar transesophageal echocardiography, we calculated AV area by means of the standard continuity method and by a modified method involving planimetric LVOT area.We found 54 circular, 37 horizontal-oval, 8 vertical-oval, and 10 irregular LVOTs. Area derived by direct planimetry correlated better with the modified than the standard continuity method (r=0.89 vs r=0.85; both P=0.0001). Valve areas of patients with mild, moderate, or severe AS by planimetry were more often mischaracterized with use of the standard than modified method (29 vs 18; P <0.0001). Horizontal-oval AV area derived by planimetry (1.28 ± 0.55 cm2) was underestimated by the standard method (1.05 ± 0.47 cm2; P=0.001), but not by the modified method. Congenital AV morphology and low cardiac index were the only multivariate predictors of horizontal-oval shape. Low cardiac index was the only predictor of noncircular shape.More than half our patients with AS had noncircular LVOTs. Using the modified method reduces mischaracterizations of AS severity. Congenital AV morphology and low cardiac index predict horizontal-oval or noncircular shape. These data suggest the value of direct LVOT measurement to calculate AS severity in patients who have congenital AV or a low cardiac index.  相似文献   
3.
Dermatofibrosarcoma protuberance of head and neck is a rare neoplasm and accounts for less than one percent of Head and Neck Neoplasm. The objective of this report is to understand etiology, presentation, histopathologic identification and treatment option for this tumour. The goal of current report is to acquaint the clinician with presentation and treatment option for this disease.  相似文献   
4.
We present two cases of neonatal pleural effusion, a relatively rare condition, most commonly due to chylothorax. One had bilateral hypoplastic lungs and the other suffered birth asphyxia. Both died before any treatment could be initiated.  相似文献   
5.
There are very few reported cases of milk of calcium in the ureter. Its presence in the ureter is quite unusual and is the subject of the present report.  相似文献   
6.
7.
Bhatia  G.  S.  Sosin  M.  D.  Patel  J.  V.  孙凯 《世界核心医学期刊文摘》2006,2(8):58-59
目的:本研究旨在明确左心室收缩功能障碍在临床类风湿病(RD)患者中是否较正常人群中更常见,并评价脑利钠肽(BNP)的诊断价值。背景:RD患者罹患缺血性心脏病的风险增加,而采用超声心动图评估RD患者心功能不全的大型研究却少见。假定左心室收缩功能障碍在RD患者中较正常人群中更为  相似文献   
8.
Retropharyngeal abscesses were fairly common in preantibiotic era but the advent of antibiotics has reduced the overall incidence of these abscesses. They still continue to occur specially in developing world and carry significant morbidity and even mortality if not managed properly. The prevalence of this abscess in the young children pose a bigger challenge, as the examination of oral cavity is difficult. Emphasis is placed on the age, sex, type, and duration of symptoms, bacteriology, methodology of diagnosis, therapy and complications. With proper antibiotic cover and surgical management, majority of patients today survive without major residual squeal. Hereby we present a series of 15 cases of retropharyngeal abscess.  相似文献   
9.
Introduction Hydatid cysts of the lung are quite frequent in our country. Some patients have additional cysts in the liver. Though most of the liver cysts remain asymptomatic for long time, but may be symptomatic with increasing size. Surgical removal is the treatment of choice for both lung & liver cysts. Aim of the study was to establish suitability of one stage surgery for pulmonary & hepatic hydatid cysts. Methods From 1996 through 2003 we operated on 216 pulmonary hydatid cysts, out of which 42 patients had hydatid cysts in the right lung as well as in the right lobe of liver. Right thoracotomy was done to remove the lung hydatids followed by phrenotomy to remove the liver cysts. Results Right thoracotomy was done in 42 patients having hydatid cysts of lung & liver. In 36 patients, cysts were removed, bronchial leaks were sutured & residual cavities were obliterated. Out of rest 6 patients, having dense adhesions or destruction of pulmonary parenchyma, 4 had segmentectomy & 2 had lobectomy. Right phrenotomy was then done with radial incision above the palpated liver cysts. Hydatid cyst was removed from liver. Cavity and remaining pericystic liver tissue was inverted with sutures. Water seal chest drain & subdiaphragmatic drain were placed. Post operative albendazole was continued for 3 months in the dose of 10–20 mg/kg with a gap of 2 weeks after each month. Post operative recovery was uneventful in most of the cases. However, air leak continued for almost 3 weeks in 4 patients & 3 months in one patient. There was no death. Conclusion Surgical management of pulmonary and hepatic hydatids with one stage right thoracotomy & phrenotomy is a suitable option. It avoids additional laparotomy and thereby additional cost & hospital stay. Results are quite satisfactory.  相似文献   
10.
Restless legs syndrome in Parkinson's disease: a case-controlled study.   总被引:5,自引:0,他引:5  
Restless legs syndrome (RLS) is a disorder of motor activity with a circadian pattern, occurring frequently in patients with Parkinson's disease (PD). We sought to estimate the prevalence of RLS in Indian PD patients. One hundred twenty-six consecutive PD patients and 128 healthy age- and sex-matched controls were evaluated using a predesigned questionnaire. RLS was present in 10 of 126 cases of PD (7.9%) and 1 of 128 controls (0.8%, P = 0.01). PD patients with RLS were older than those without RLS (63.70 +/- 7.80 years vs. 57.37 +/- 10.04 years; P = 0.05) and had higher prevalence of depression (40% vs. 10.3%; P = 0.023). No demographic factors or factors related to PD correlated with the presence or severity of RLS. RLS is more common among patients with PD than controls. A greater medical recognition of this disorder is needed in view of available effective treatment.  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