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   3979篇
  免费   205篇
  国内免费   51篇
耳鼻咽喉   44篇
儿科学   63篇
妇产科学   40篇
基础医学   515篇
口腔科学   66篇
临床医学   259篇
内科学   988篇
皮肤病学   60篇
神经病学   235篇
特种医学   204篇
外科学   823篇
综合类   11篇
预防医学   86篇
眼科学   32篇
药学   249篇
中国医学   5篇
肿瘤学   555篇
  2023年   43篇
  2022年   92篇
  2021年   146篇
  2020年   55篇
  2019年   108篇
  2018年   101篇
  2017年   88篇
  2016年   114篇
  2015年   117篇
  2014年   161篇
  2013年   145篇
  2012年   243篇
  2011年   271篇
  2010年   162篇
  2009年   128篇
  2008年   193篇
  2007年   201篇
  2006年   215篇
  2005年   233篇
  2004年   255篇
  2003年   234篇
  2002年   247篇
  2001年   50篇
  2000年   37篇
  1999年   56篇
  1998年   57篇
  1997年   53篇
  1996年   49篇
  1995年   36篇
  1994年   38篇
  1993年   39篇
  1992年   30篇
  1991年   28篇
  1990年   27篇
  1989年   18篇
  1988年   19篇
  1987年   24篇
  1986年   14篇
  1985年   11篇
  1984年   9篇
  1983年   7篇
  1982年   8篇
  1981年   9篇
  1980年   10篇
  1979年   7篇
  1977年   5篇
  1974年   5篇
  1972年   6篇
  1971年   5篇
  1970年   6篇
排序方式: 共有4235条查询结果,搜索用时 0 毫秒
71.
Digestive Diseases and Sciences - Hepatocellular carcinoma develops in some patients with hepatitis C virus (HCV), even after achieving sustained virological response (SVR). We examined factors...  相似文献   
72.
BACKGROUND: Endoscopic sphincterotomy is difficult and sometimes impossible in patients who have undergone gastrectomy or partial gastrectomy with Billroth II reconstruction. For such patients, a novel technique was developed in which endoscopic sphincterotomy is performed via percutaneous transhepatic cholangioscopy. This report describes an initial experience with this technique. METHODS: After dilation of the percutaneous fistula, a cholangioscope with a push-type sphincterotome attached was inserted into the bile duct via the fistula and then through the papilla into the duodenum. The tip of the instrument then was retroverted to obtain a frontal view of the papilla. Then, a sphincterotomy incision was extended to the proximal, orad margin of the papillary eminence. OBSERVATIONS: Percutaneous transhepatic biliary drainage was performed in 3 patients with obstructive jaundice and bile duct stones. In all patients, percutaneous transhepatic cholangioscopic sphincterotomy was performed successfully, without procedure-related complication. Thereafter, all stones and stone fragments cleared from the duct by spontaneous migration. CONCLUSIONS: Endoscopic sphincterotomy via percutaneous transhepatic cholangioscopy potentially is an innovative technique for endoscopic sphincterotomy in patients with an endoscopically inaccessible papilla.  相似文献   
73.
Partial intertarsal joint arthrodesis was performed on 12 feet of 11 patients as a surgical treatment for planovalgus deformity of the foot and lesions of the intertarsal joints caused by rheumatoid arthritis. Single arthrodesis was performed on the talocalcaneal joint in eight feet, two of which underwent simultaneous total ankle arthroplasty, and on the talonavicular joint in two feet. Double arthrodesis was done on the talocalcaneal and talonavicular joints in one foot and on the talonavicular and calcaneocuboid joints in one foot. Screws or staples were used for fixation. Patients were followed for 2 years to 8 years 7 months (average 4 years 3 months). Osseous fusion was achieved in all feet, and satisfactory pain relief was obtained in all cases except one. We performed this surgery in patients who were relatively active, and the results indicated that arthrodesis of a small number of joints that caused pain and deformity was effective in reducing pain and correcting the deformity. We concluded that partial tarsal arthrodesis should be performed on a limited number of joints during the early stages of planovalgus deformity of the foot because more joints are found to be fixed during the advanced stages. However, progression of the osteoarthritis was found in the neighboring joints. Close follow-up observation is needed.  相似文献   
74.
75.
We herein report the definitive diagnosis of rectovaginal endometriosis in two cases. Case 1 involved a 46-year-old woman with abdominal pain and hematochezia. The diagnosis after the first and second examinations using lower gastrointestinal (GI) endoscopy was unclear. Differential diagnoses included mucosa-associated lymphoid tissue and colorectal cancer. The third lower GI endoscopy with a targeted biopsy, performed during menstruation, confirmed rectovaginal endometriosis. Case 2 involved a 38-year-old woman with hematochezia. Lower GI endoscopy during menstruation revealed rectovaginal endometriosis. When rectovaginal or bowel endometriosis is suspected, lower GI endoscopy and a targeted biopsy during menstruation can prevent unnecessary surgery.  相似文献   
76.
Annals of Nuclear Medicine - Although previous studies have investigated age and gender effects on striatal subregional dopamine transporter (DaT) binding, these studies were mostly based on a...  相似文献   
77.
Effects of smoking on white matter lesions, such as lacunar infarction and leukoaraiosis, are still controversial. We hypothesized that the endothelial NO synthase (eNOS) genotype was a modulating factor for the effect of smoking on cerebral circulation. We took a cross-sectional population from the participants of a health examination to study the effects of smoking and a single-nucleotide polymorphism in the eNOS gene, T-786C. Smokers and nonsmokers were defined as having a smoking index (cigarettes per day times years) of >/=200 and 0, respectively. One hundred sixty-six male nonsmokers and 344 male smokers were recruited. Cerebral blood flow was measured by the (133)Xe inhalation method. Genotyping of T-786C was performed by using a newly developed allele-specific polymerase chain reaction. Smokers were exposed to greater oxidative stress, as estimated by urinary F(2)-isoprostane excretion. In smokers, CC homozygotes of T-786C showed a significant decrease of cerebral blood flow (56.6+/-13.3, 57.6+/-11.5, and 44.0+/-7.2 mL/min per 100 g tissue for TT, TC, and CC, respectively; P=0.03 by ANOVA) and a significant increase of cerebrovascular resistance, whereas the eNOS genotype did not affect these parameters in nonsmokers. This result indicated that the eNOS genotype could modify cerebrovascular circulation in a general population by potentiating the adverse effect of smoking.  相似文献   
78.
79.
European Journal of Clinical Microbiology & Infectious Diseases - The aim of this study is to clarify the characteristics of gram-negative bacteremia (GNB), including extended-spectrum...  相似文献   
80.
Human T‐cell leukemia virus type 1 (HTLV‐1) carriers are rarely subject to inflammatory disorders in multiple organs, other than the well‐known complication, adult T‐cell leukemia/lymphoma (ATLL). HTLV‐1 associated bronchiolo‐alveolar disorder (HABA) has been proposed as an immune mediated pulmonary reaction seen rarely in HTLV‐1 carriers. The reported clinico‐pathological patterns of HABA are diffuse panbronchiolitis (DPB) and lymphoid interstitial pneumonia (LIP). We here report three cases of HTLV‐1 carriers showing miliary micro‐nodules throughout both lungs. Microscopic examination in the video assisted thoracic surgery biopsies demonstrated that all cases had multiple discrete micro‐nodules which consisted of marked lymphoid infiltration, granulomas, eosinophils and a few foci of necrosis inside the granuloma. No findings indicating ATLL, other neoplastic conditions, infection or interstitial pneumonia, including DPB and LIP, were present following panels of special staining and immunohistochemical examinations. Two patients improved without treatment within one month, with no evidence of recurrence after 7 years. One patient showed slow deterioration of lung reticular shadows in spite of a low dose corticosteroid therapy (prednisolone 10 mg/day). We believe these cases may be a newly recognized variant of HABA.  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