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   42434篇
  免费   1962篇
  国内免费   228篇
耳鼻咽喉   499篇
儿科学   769篇
妇产科学   377篇
基础医学   5399篇
口腔科学   1155篇
临床医学   2787篇
内科学   10321篇
皮肤病学   618篇
神经病学   3458篇
特种医学   1635篇
外科学   6886篇
综合类   277篇
预防医学   1495篇
眼科学   894篇
药学   3568篇
中国医学   132篇
肿瘤学   4354篇
  2023年   179篇
  2022年   372篇
  2021年   677篇
  2020年   338篇
  2019年   479篇
  2018年   638篇
  2017年   513篇
  2016年   645篇
  2015年   691篇
  2014年   918篇
  2013年   1219篇
  2012年   1866篇
  2011年   2040篇
  2010年   1142篇
  2009年   993篇
  2008年   1858篇
  2007年   2036篇
  2006年   2091篇
  2005年   2218篇
  2004年   2167篇
  2003年   2100篇
  2002年   2182篇
  2001年   1357篇
  2000年   1464篇
  1999年   1338篇
  1998年   625篇
  1997年   501篇
  1996年   475篇
  1995年   410篇
  1994年   416篇
  1993年   379篇
  1992年   894篇
  1991年   813篇
  1990年   816篇
  1989年   845篇
  1988年   771篇
  1987年   698篇
  1986年   658篇
  1985年   624篇
  1984年   504篇
  1983年   378篇
  1982年   248篇
  1981年   201篇
  1980年   220篇
  1979年   316篇
  1978年   258篇
  1977年   202篇
  1974年   183篇
  1973年   167篇
  1969年   176篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.
BackgroundTIAregistry.org is an international cohort of patients with transient ischemic attack (TIA) or minor stroke within 7 days before enrollment in the registry. Main analyses of 1-year follow-up data have been reported.5 We conducted subanalysis on the baseline and 1-year follow-up data of Japanese patients.MethodsThe patients were classified into 2 groups based on Japanese ethnicity, Japanese (345) and non-Japanese (3238), and their baseline data and 1-year event rates were compared. We also determined risk factors and predictors of 1-year stroke.ResultsCurrent smoking, regular alcohol drinking, intracranial arterial stenosis, and small vessel occlusion; and hypertension, dyslipidemia, coronary artery disease, and extracranial arterial stenosis were more and less common among Japanese patients, respectively. Stroke risk was higher and TIA risk was lower at 1-year follow-up among Japanese patients. The baseline risk factors for recurrent stroke were diabetes, alcohol drinking, and large artery atherosclerosis. Independent predictors of 1-year stroke risk were prior congestive heart failure and alcohol consumption.ConclusionsThe two populations of patients featured differences in risk factors, stroke subtypes, and outcome events. Predictors of recurrent stroke among Japanese patients included congestive heart failure and regular alcohol drinking. Strategies to attenuate residual risk of stroke aside from adherence to current guidelines should take our Japanese-patient specific findings into account.  相似文献   
4.
The phosphodiesterase-5 (PDE-5) inhibitor, sildenafil, has been reported to produce sustained pulmonary vasodilatation in patients with pulmonary hypertension (PH). Recently, vardenafil, a more potent and selective PDE-5 inhibitor than sildenafil, has been approved for the treatment of erectile dysfunction. However, the long-term effects of oral vardenafil in patients with PH are unknown. We studied five consecutive patients with PH; one with primary pulmonary hypertension, two with chronic pulmonary thromboembolism, one with Eisenmenger syndrome (ventricular septal defect) and one with secondary pulmonary hypertension after a ventricular septal defect closure operation. In an acute hemodynamic trial, vardenafil (5 mg) significantly decreased both the pulmonary vascular resistance (PVR) and systemic vascular resistance (SVR) with an increase in cardiac output. In a chronic hemodynamic trial, the maintenance dose of vardenafil (10 to 15 mg) for 3 months significantly decreased the PVR, but not the SVR, with a 20.7% reduction of the PVR/ SVR ratio. Plasma brain natriuretic peptide (BNP) levels were also significantly decreased after 3 months. This pilot study demonstrates that long-term oral vardenafil therapy may be a safe and effective treatment for patients with PH.  相似文献   
5.
A 23-year-old man was admitted for treatment of acute exacerbation of ileitis and perianal abscess caused by Crohn's disease. After incision and drainage of the abscess, coupled with antibiotic therapy, 6-mercaptopurine (6-MP) was commenced. His white blood cell (WBC) count on day 12 after initiation of 6-MP was not decreased. However, on day 24 he was re-admitted because of severe myelosuppression (WBC: 300/microl), which was complicated by the recurrence of the perianal abscess. Myelosuppression was prolonged and required the administration of granulocyte colony stimulating factor (G-CSF). G-CSF was continued for 17 days to achieve recovery of his WBC count to a normal level.  相似文献   
6.
7.
8.
9.
We evaluated the therapeutic efficacy of miconazole (MCZ, Florid-F inj.), a new antifungal agent for parenteral use, in deep-seated fungal infections of respiratory tract system. A daily dose of 400-1,800 mg of MCZ was given intravenously for 12-38 days (mean: 23.4 days) to 7 patients: 2 patients with pulmonary aspergillosis, 1 patient with bronchial aspergillosis, 1 patient with pulmonary candidiasis and 3 patients with candidemia. One additional patient with pulmonary aspergillosis received three instillations of 20 mg of MCZ into the thoracic cavity. The clinical effects were excellent in 1, good in 4 and poor in 3 patients. The efficacy rate was 100% in 5 cases with respiratory fungal infections but 3 cases with candidemia did not respond well to the treatment. Four strains each of Aspergillus sp. and Candida sp. were identified as causative organisms. Seven of the 8 strains were eradicated by administration of MCZ. Side effects observed were irritation and heat in a leg in 1 patient, hyperlipoidemia in 2 patients and eosinophilia in 1 patient. The adverse reactions disappeared after the completion of the therapy. From the above results, we conclude that MCZ is one of the most useful antifungal agents for parenteral use as a first choice on deep-seated fungal infections in the respiratory tract.  相似文献   
10.
Computed tomography and nonoperative treatment for blunt abdominal trauma   总被引:1,自引:0,他引:1  
Studies were undertaken to determine if computed tomography (CT) could reliably assist physical examination in the initial assessment of blunt abdominal trauma, and also to examine how various abdominal injuries were managed with the guidance of CT. A total of 255 patients underwent emergency abdominal CT following blunt abdominal trauma over a period of seven years. One hundred and fifty two patients had abnormal CT scans, including 58 hepatic, 36 renal, 25 splenic and 9 pancreatic injuries as well as 67 patients with intra-abdominal hemorrhage and 21 patients with free abdominal air. A comparative study on the detection of pneumoperitoneum revealed CT to be far superior to plain radiography. One hundred and three patients had normal CT scans, all of whom were managed nonoperatively, except for three false-negative cases and two nontherapeutic cases. The patients with injury to the parenchymal organs were given nonoperative treatment if they had stable vital signs and no evidence of associated injuries demanding immediate surgery and the majority of these patients were managed well nonoperatively. CT was thus found to be a useful adjunct in the management of victims of blunt abdominal trauma, since in a rapid and noninvasive fashion, CT accurately defined the extent of parenchymal organ injury and also disclosed any other abdominal injuries.  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