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   676篇
  免费   32篇
耳鼻咽喉   8篇
儿科学   46篇
妇产科学   9篇
基础医学   81篇
口腔科学   5篇
临床医学   27篇
内科学   171篇
皮肤病学   5篇
神经病学   97篇
特种医学   9篇
外科学   78篇
综合类   15篇
预防医学   30篇
眼科学   13篇
药学   63篇
中国医学   4篇
肿瘤学   47篇
  2023年   5篇
  2021年   16篇
  2020年   9篇
  2019年   9篇
  2018年   10篇
  2017年   6篇
  2016年   22篇
  2015年   13篇
  2014年   17篇
  2013年   17篇
  2012年   28篇
  2011年   35篇
  2010年   19篇
  2009年   24篇
  2008年   30篇
  2007年   25篇
  2006年   23篇
  2005年   30篇
  2004年   37篇
  2003年   36篇
  2002年   27篇
  2001年   18篇
  2000年   21篇
  1999年   26篇
  1997年   4篇
  1996年   4篇
  1995年   9篇
  1992年   11篇
  1991年   9篇
  1990年   7篇
  1989年   7篇
  1987年   10篇
  1986年   5篇
  1985年   7篇
  1984年   6篇
  1983年   6篇
  1982年   3篇
  1981年   4篇
  1980年   9篇
  1979年   12篇
  1978年   11篇
  1977年   10篇
  1976年   8篇
  1975年   5篇
  1974年   9篇
  1973年   6篇
  1972年   8篇
  1971年   4篇
  1970年   6篇
  1969年   7篇
排序方式: 共有708条查询结果,搜索用时 0 毫秒
71.
72.
P G?r?g  V V Kakkar 《Atherosclerosis》1987,65(1-2):99-107
A new technique was elaborated for measuring LDL uptake by rat aortic endothelial cells in vivo, using a fluorescent marker (Dil)-labelled LDL and quantifying the fluorescence in cells selectively removed from the aorta. This technique was used to study the endothelial uptake of LDL modified by activated human monocytes (LDL-A) in comparison with native LDL (LDL-N) protected from oxidation by vitamin E during the preparation. Incubation of LDL with activated monocytes increased endothelial uptake in vivo by 9.3-fold and also by 4.4-fold in cultured confluent porcine endothelium. In contrast, only a 1.5-fold increase in uptake of LDL-A was observed in sparse cultures. Cytotoxicity of monocyte-altered or native LDL did not differ as measured by the [3H]deoxyglucose-release test on cultured endothelium. Our results suggest that modification of LDL in the circulation by monocytes may make an important contribution to atherogenesis.  相似文献   
73.
BackgroundAsymptomatic atrial fibrillation is often detected incidentally. Prognosis and optimal therapy for asymptomatic compared with symptomatic atrial fibrillation is uncertain. This study compares clinical characteristics, treatment, and 2-year outcomes of asymptomatic and symptomatic atrial fibrillation presentations.MethodsGlobal Anticoagulant Registry in the Field-Atrial Fibrillation (GARFIELD-AF) is a global, prospective, observational study of newly diagnosed atrial fibrillation with ≥1 stroke risk factors (http://www.clinicaltrials.gov, unique identifier: NCT01090362). Patients were characterized by atrial fibrillation-related symptoms at presentation and the CHA2DS2-VASc score. Two-year follow-up recorded anticoagulation patterns (vitamin K antagonist, direct oral anticoagulants, parenteral therapy) and outcomes (stroke/systemic embolism, all-cause mortality, and bleeding).ResultsAt presentation, of 52,032 eligible patients, 25.4% were asymptomatic and 74.6% symptomatic. Asymptomatic patients were slightly older (72 vs 70 years), more often male (64.2% vs 52.9%), and more frequently initiated on anticoagulation ± antiplatelets (69.4% vs 66.0%). No difference in events (adjusted hazard ratios, 95% confidence interval) for nonhemorrhagic stroke/systemic embolism (1.19, 0.97-1.45), all-cause mortality (1.06, 0.94-1.20), or bleeding (1.02, 0.87-1.19) was observed. Anticoagulation was associated with comparable reduction in nonhemorrhagic stroke/systemic embolism (0.59, 0.43–0.82 vs 0.78, 0.65–0.93) and all-cause mortality (0.69, 0.59-0.81 vs 0.77, 0.71-0.85) in asymptomatic versus symptomatic, respectively.ConclusionsMajor outcomes do not differ between asymptomatic and symptomatic atrial fibrillation presentations and are comparably reduced by anticoagulation. Opportunistic screening-detected asymptomatic atrial fibrillation likely has the same prognosis as asymptomatic atrial fibrillation at presentation and likely responds similarly to anticoagulation thromboprophylaxis.  相似文献   
74.
There have been animal and human studies looking at intracoronary (IC) use of abciximab with good short-term clinical outcomes. There exists no data comparing intracoronary with intravenous (IV) administration of abciximab beyond 30 days. We compared the clinical outcomes between the IC (n = 101) and IV (n = 72) group of patients. Patients who had coronary stenting and received abciximab were included in the study. All the patients received the standard systemic bolus dose of abciximab 0.25 mg/kg either via the IC or IV route, followed by a 12-hr IV infusion at 0.125 microg/kg/min. The 6-month composite endpoint of death or myocardial infarction was slightly higher in the IV (13.9%) than in the IC group (5.9%; P = 0.04). The frequency of bleeding complications was similar in both groups. The IC bolus route of abciximab may be superior to the intravenous route. Prospective randomized trials are warranted to validate these findings.  相似文献   
75.
76.
The advent of smaller gauge instrumentation allows for minimally invasive vitreoretinal surgery (MIVS) as compared to conventional pars plana vitrectomy. Sutureless posterior segment surgery has the advantages of faster wound healing, minimal surgical trauma, decreased convalescence period besides reduced postoperative astigmatism; however, slower gel removal and limited peripheral vitreous dissection are disadvantages with smaller gauge systems. We herein describe a new technique combining 23-gauge and 20-gauge vitrectomy to improve the effectiveness and outcomes of vitreoretinal surgery.  相似文献   
77.
Forty patients of histologically proven esophageal carcinoma were subjected to computed tomography (CT) with the objective to assess its reliability in preoperative evaluation of these patients. The findings were confirmed on surgery in twenty five of these patients, thought to be resectable. Bronchoscopy was performed to evaluate bronchial tree in cases of tumor of upper and middle third of esophagus. CT was found to be sensitive in predicting the location and size of tumor, in assessing invasion of tracheo-bronchial tree, spread to liver, celiac and left gastric nodes. However, it was not successful in picking up metastatic spread to local periesophageal nodes in five cases and celiac in one case. The study concluded CT should be carried out for preoperative evaluation of esophageal carcinoma to select operable cases and avoid unnecessary radicle surgery in advanced cases.  相似文献   
78.
The dystrophin glycoprotein complex (DGC) is a specialization of cardiac and skeletal muscle membrane. This large multicomponent complex has both mechanical stabilizing and signaling roles in mediating interactions between the cytoskeleton, membrane, and extracellular matrix. Dystrophin, the protein product of the Duchenne and X-linked dilated cardiomyopathy locus, links cytoskeletal and membrane elements. Mutations in additional DGC genes, the sarcoglycans, also lead to cardiomyopathy and muscular dystrophy. Animal models of DGC mutants have shown that destabilization of the DGC leads to membrane fragility and loss of membrane integrity, resulting in degeneration of skeletal muscle and cardiomyocytes. Vascular reactivity is altered in response to primary degeneration in striated myocytes and arises from a vascular smooth muscle cell-extrinsic mechanism.  相似文献   
79.
Venous thromboembolism is a common problem in cancer patients. It complicates both the surgical management of those with cancer and has been associated with varying risk for the development of clinical thromboembolism in patients receiving chemotherapy. Unfractionated and low-molecular-weight heparin have been validated both in terms of their efficacy and safety, in the prevention of venous thromboembolic disease in cancer patients undergoing surgical intervention and for the primary treatment and secondary prevention of recurrent venous thromboembolism. Beyond their uses in the prevention and treatment of thrombosis, low-molecular-weight heparins have recently been shown to prolong survival in patients with solid tumour malignancy.  相似文献   
80.
Telangiectatic osteosarcoma (TOS) is one of the 8 subtypes of osteosarcoma that infrequently affects the spine. The radiopathological features of TOS overlap with those of more benign entities, most commonly the aneurysmal bone cyst), and therefore is a significant diagnostic challenge. It is a rare but well-described entity in the thoracolumbar and sacral spine, and to the authors' knowledge has not been previously reported in the cervical spine. The authors report the case of a 15-year-old boy who presented with a 6-month history of neck pain and torticollis. He underwent preoperative glue embolization followed by a staged subtotal C-5 spondylectomy and posterior fusion for a C-5 vertebral body lytic expansile lesion. Histopathological examination showed the lesion to be TOS. The surgery was followed by adjuvant radiation and chemotherapy with a favorable outcome at the 1-year follow-up. This report reiterates that TOS is an important differential diagnosis for aneurysmal bone cyst and giant-cell tumor of the spine, as its biological behavior and clinical outcome differ from those of these more benign lesions, which it mimics.  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