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   1404篇
  免费   78篇
耳鼻咽喉   8篇
儿科学   20篇
妇产科学   9篇
基础医学   182篇
口腔科学   11篇
临床医学   157篇
内科学   353篇
皮肤病学   28篇
神经病学   91篇
特种医学   86篇
外科学   249篇
综合类   9篇
一般理论   1篇
预防医学   62篇
眼科学   26篇
药学   69篇
中国医学   1篇
肿瘤学   120篇
  2022年   10篇
  2021年   21篇
  2020年   17篇
  2019年   17篇
  2018年   22篇
  2017年   19篇
  2016年   32篇
  2015年   37篇
  2014年   48篇
  2013年   46篇
  2012年   102篇
  2011年   107篇
  2010年   79篇
  2009年   53篇
  2008年   101篇
  2007年   91篇
  2006年   79篇
  2005年   86篇
  2004年   75篇
  2003年   64篇
  2002年   56篇
  2001年   15篇
  2000年   23篇
  1999年   14篇
  1998年   16篇
  1997年   10篇
  1996年   7篇
  1994年   6篇
  1992年   17篇
  1991年   13篇
  1990年   14篇
  1989年   14篇
  1988年   11篇
  1987年   11篇
  1986年   11篇
  1985年   9篇
  1984年   9篇
  1983年   7篇
  1980年   4篇
  1979年   8篇
  1978年   10篇
  1974年   6篇
  1973年   4篇
  1972年   7篇
  1971年   4篇
  1970年   5篇
  1967年   5篇
  1966年   5篇
  1965年   4篇
  1949年   7篇
排序方式: 共有1482条查询结果,搜索用时 15 毫秒
11.
Six-thousand-seven-hunderd and forty-nine positive urine cultures from a large metropolitan Veterans Administration hospital were analyzed with respect to the organisms isolated and their antimicrobial sensitivies. A predicted therapeutic efficacy index was calculated for each antimicrobial agent tested. Gram-negative pathogens accounted for 84% of the infections. Proteus infections outnumbered those due to strains ofEscherichia coli. Gentamycin was found to be the most effective antimicrobial agent.  相似文献   
12.
Summary Eighteen patients with myeloproliferative syndrome (14 with chronic myeloid leukemia, four with essential thrombocytosis) were investigated for modulation of HLA antigens on peripheral blood lymphocytes, monocytes, and hematopoietic precursors during IFN therapy as a sign of potentially increased immune recognition of malignant cells. After 1 month of IFN therapy, an increased number of monocytes and hematopoietic precursor cells, but not of lymphocytes, expressed HLADQ antigens. In addition, a strong induction of HLA class-I antigens was found on both hematopoietic progenitors and normal peripheral blood mononuclear cells. With daily injections of IFN in the first month of therapy stimulation continuously increased, suggested a major effect of IFNa on hematopoietic progenitors with sustained enhanced expression of HLA class-I antigens during differentiation of myelomonocytic cells. HLA class-I antigen expression was consistently augmented by IFN in all patients, irrespective of their hematological response.This work was supported by theElse Übelmesser Stiftung and theDeutsche Forschungsgemeinschaft, Sonderforschungsbereich 120, projects A3 and D4  相似文献   
13.
14.
The authors present a case of heparin-induced thrombocytopenia and thrombosis (HITT) that occurred after aneurysmal subarachnoid hemorrhage (SAH), and they review the relevant literature. An immune-mediated syndrome, HITT is characterized by moderate thrombocytopenia and paradoxical vascular thromboses. Although it has been estimated in prospective studies that HITT occurs in between 1 and 3% of patients receiving heparin, it is underrecognized in the neurosurgical literature. In the present case, a 49-year-old woman underwent clipping of a right posterior communicating artery aneurysm after suffering a Hunt and Hess Grade III SAH. She had an uncomplicated postoperative course with good clip positioning and no vasospasm observed on a cerebral angiogram obtained on Day 7. On Day 23, the patient developed a right hemiparesis and experienced a grand mal seizure. A head computerized tomography scan revealed a hemorrhagic infarct in the left middle cerebral artery distribution. Repeated cerebral angiograms did not show vasospasm. She was thrombocytopenic (platelet count as low as 46 x 10(9)/L on Day 28 compared with 213 x 10(9)/L on Day 1) and had been receiving heparin flushes to maintain intravenous catheter patency. An assay for HITT-associated antibodies was positive. The heparin flushes were discontinued and the platelet count recovered (121 x 10(9)/L). She improved neurologically, but was left with a significant right hemiparesis at discharge. This patient had assay-proven heparin-induced thrombocytopenia despite minimal exposure to heparin. Because there was no evidence of vasospasm or other factors to account for her delayed hemorrhagic infarction, an HITT-related disorder seemed most likely. Despite a large body of literature describing HITT in nonneurosurgical patients, only three previous neurosurgical cases have been published. This case report may serve to heighten awareness of this disorder.  相似文献   
15.
Only a few large series of posterior cerebral artery (PCA) stroke exist, and clinical features and causes have not been studied as extensively as in other vascular territories. The PCA syndrome includes more clinical signs than the well-known visual field deficits. Concomitant findings are frequently sensory, slight motor and neuropsychological deficits. Unilateral headaches are the common presenting symptom making complicated migraine an important differential diagnosis. Combined deep and superficial PCA territory infarcts involving the lateral thalamus are more frequent than commonly assumed and are mostly associated with sensory and reversible slight motor deficits. Occlusion of the precommunal PCA segment with associated paramedian midbrain infarction causes severe motor deficits, oculomotor signs, and decreased consciousness and has a poorer outcome than other PCA territory infarcts. Embolism from a cardiac or undetermined source is the leading mechanism accounting for up to half of the cases, whereas arterial embolism from significant proximal vertebrobasilar disease is less frequent. Local atherothrombotic stenosis or occlusion of the PCA is uncommon. In spite of thorough diagnostic evaluation, the etiology of PCA territory infarction cannot be determined in at least one quarter of patients. Among the rare causes of PCA territory infarction carotid artery disease is important while the significance of migraine remains controversial.  相似文献   
16.
17.
18.
19.
20.
Quality assurance becomes an increasingly important part of clinical medicine and of the field of endoscopy. Endoscopic sphincterotomy is associated with a fairly high complication rate. We aimed to assess our quality of sphincterotomy for benchmarking by using a prospective electronic database registry, and to identify potential risk factors for post-interventional complications. Over 2 years, 471 sphincterotomies were performed in a single tertiary referral centre. Patient- and procedure-related variables were prospectively recorded with the support of a multi-centre international sphincterotomy registry. Multivariate analysis was performed. The overall post-interventional complication rate was 9.3%. Pancreatitis happened in 5.5%, bleeding in 2.1%, perforation in 1.3%, and cholangitis in 0.4%. In the multivariate analysis following variables remained highly significant and predictive for complications: ‘papilla only in lateral view’ (p=0.001), antiplatelet therapy (p=0.024), and opacification with contrast up to the pancreatic tail (p=0.001). The primary success rate of sphincterotomy was 95.1%. The rate of post-interventional pancreatitis did not differ significantly regardless of the presence of prophylactic pancreatic stent (p=0.56). The outcome of sphincterotomy in our centre matches with literature data. The extent of pancreatic duct opacification has an influence on the pancreatitis rate. Prevention of pancreatitis by inserting pancreatic stents is not confirmed.  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