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   1847篇
  免费   98篇
  国内免费   11篇
耳鼻咽喉   53篇
儿科学   12篇
妇产科学   37篇
基础医学   251篇
口腔科学   24篇
临床医学   94篇
内科学   601篇
皮肤病学   5篇
神经病学   123篇
特种医学   99篇
外科学   337篇
综合类   7篇
一般理论   1篇
预防医学   39篇
眼科学   9篇
药学   70篇
中国医学   1篇
肿瘤学   193篇
  2023年   12篇
  2022年   27篇
  2021年   66篇
  2020年   21篇
  2019年   34篇
  2018年   58篇
  2017年   35篇
  2016年   60篇
  2015年   49篇
  2014年   64篇
  2013年   78篇
  2012年   130篇
  2011年   153篇
  2010年   75篇
  2009年   63篇
  2008年   126篇
  2007年   116篇
  2006年   121篇
  2005年   123篇
  2004年   121篇
  2003年   94篇
  2002年   96篇
  2001年   28篇
  2000年   28篇
  1999年   20篇
  1998年   17篇
  1997年   21篇
  1996年   14篇
  1995年   16篇
  1994年   10篇
  1993年   11篇
  1992年   6篇
  1991年   6篇
  1990年   6篇
  1989年   5篇
  1988年   3篇
  1987年   9篇
  1986年   7篇
  1985年   4篇
  1984年   3篇
  1983年   3篇
  1982年   5篇
  1981年   2篇
  1980年   3篇
  1979年   1篇
  1977年   1篇
  1976年   1篇
  1971年   1篇
  1970年   2篇
  1969年   1篇
排序方式: 共有1956条查询结果,搜索用时 0 毫秒
51.
Primary iliac venous aneurysm is an extremely rare clinical entity. We report a case of primary external iliac venous aneurysm containing an intraluminal thrombus that caused pulmonary thromboembolism in a 22-year-old woman. The aneurysm and pulmonary emboli were detected during examination for sudden onset of dyspnea. After receiving anticoagulation and thrombolytic therapy, the patient underwent aneurysm resection. We devised venoplasty using a dual-row saphenous vein patch to cover the large defect of the vessel wall. Primary iliac venous aneurysms associated with pulmonary thromboembolism are uncommon and surgical repair is made difficult by the fragility of the affected vessel. We reviewed the clinical features of this unusual entity.  相似文献   
52.
53.
A 51-year-old man was admitted to our hospital because of hematochezia and painful keratotic plaques involving both hands. He had gastrointestinal polyposis, and a history of liver hemangiomas and thyroid tumor. Numerous papules on the face and papillomatosis on the oral mucosa were present. A diagnosis was made as a typical case of Cowden's disease according to the criteria proposed by Salem and Steck (J Am Acad Dermatol 8: 686, 1983). The patient was not correctly diagnosed initially in spite of typical manifestations of Cowden's disease, mainly due to his concomitant manifestations which occurred chronologically.  相似文献   
54.
We herein report a case of large-vessel vasculitis in a 57-year-old woman who developed an intermittent fever and weight loss. While contrast-enhanced computed tomography was noncontributory, positron emission tomography-computed tomography (PET-CT) revealed the diffuse, intense uptake of fluorodeoxyglucose (FDG) in the aorta and its branches. Although she had no signs of relapse after successful oral corticosteroid therapy, PET-CT at 30 months revealed a persistent FDG uptake in the large vessels, which warranted regular follow-up imaging for vascular complications. In cases with an intense FDG uptake at the diagnosis, PET-CT follow-up after clinical remission may help predict the risk of relapse and vascular complications.  相似文献   
55.

Background

Peripheral artery disease (PAD), a diffuse manifestation of atherothrombosis, is a major cardiovascular threat. Although platelets are primary mediators of atherothrombosis, their role in the pathogenesis of PAD remains unclear.

Objectives

The authors sought to investigate the role of platelets in a cohort of symptomatic PAD.

Methods

The authors profiled platelet activity, mRNA, and effector roles in patients with symptomatic PAD and in healthy controls. Patients with PAD and carotid artery stenosis were recruited into ongoing studies (NCT02106429 and NCT01897103) investigating platelet activity, platelet RNA, and cardiovascular disease.

Results

Platelet RNA sequence profiling mapped a robust up-regulation of myeloid-related protein (MRP)-14 mRNA, a potent calcium binding protein heterodimer, in PAD. Circulating activated platelets were enriched with MRP-14 protein, which augmented the expression of the adhesion mediator, P-selectin, thereby promoting monocyte–platelet aggregates. Electron microscopy confirmed the firm interaction of platelets with monocytes in vitro and colocalization of macrophages with MRP-14 confirmed their cross talk in atherosclerotic manifestations of PAD in vivo. Platelet-derived MRP-14 was channeled to monocytes, thereby fueling their expression of key PAD lesional hallmarks and increasing their directed locomotion, which were both suppressed in the presence of antibody-mediated blockade. Circulating MRP-14 was heightened in the setting of PAD, significantly correlated with PAD severity, and was associated with incident limb events.

Conclusions

The authors identified a heightened platelet activity profile and unraveled a novel immunomodulatory effector role of platelet-derived MRP-14 in reprograming monocyte activation in symptomatic PAD. (Platelet Activity in Vascular Surgery and Cardiovascular Events [PACE]; NCT02106429; and Platelet Activity in Vascular Surgery for Thrombosis and Bleeding [PIVOTAL]; NCT01897103)  相似文献   
56.
57.

Background

The Kidney Disease: Improving Global Outcomes (KDIGO) group proposed to adopt the 48-h time window for the 0.3  mg/dL rise in serum creatinine (sCr) proposed by the Acute Kidney Injury Network (AKIN) group as a modification to the original risk, injury, failure, loss, and end-stage renal disease criteria, keeping the 7-day window for the 50 % increase in sCr from baseline. The present study evaluates the prevalence of acute kidney injury (AKI) and the accuracy of predicting mortality based on the KDIGO and AKIN criteria.

Patients and methods

We retrospectively studied a cohort of 2579 patients admitted to the intensive care unit of Nagoya University Hospital between 2005 and 2009.

Results

The total AKI prevalence was higher according to the KDIGO than to the AKIN criteria (38.4 versus 29.5 %). In-hospital mortality rates were higher among 238 patients classified as non-AKI by the AKIN but AKI by the KDIGO criteria than among those classified as non-AKI by both criteria (7.1 versus 2.7 %). Survival curves generated using KDIGO significantly differed among all stages, but not between AKIN stages I and II. Multivariate analysis showed that KDIGO criteria were better in a statistical model than the AKIN criteria according to the Akaike information criterion. Harrell’s C statistic was greater for the KDIGO than for the AKIN criteria.

Conclusions

The KDIGO criteria have improved sensitivity without compromising specificity for AKI and might predict mortality at least as well as the AKIN criteria.  相似文献   
58.
Division of the splenic vein was performed in 29 patients who underwent pancreatoduodenectomy to achieve lymph node dissection and neural resection around the superior mesenteric artery. The basic protocol for the splenic vein reconstruction to reduce congestion of the spleen and stomach is as follows. When the inferior mesenteric vein (IMV) drained into the splenic vein, the confluence was preserved without reconstruction of the splenic vein. When the IMV drained into the superior mesenteric vein (SMV) or the splenomesenteric angle, the division of the IMV and spleno-IMV anastomosis were performed. In postoperative venography, nine patients showed downward flow (from the splenic vein to the IMV) and three patients showed upward flow (from the IMV to the splenic vein). Postoperative computed tomography scans showed venous dilatation and splenomegaly in the upward flow group; there were no patients in the downward flow group. In selected patients, splenic vein reconstruction is necessary to reduce congestion of the spleen and stomach. When the flow is downward, spleno-IMV flow should be preserved. When the flow is upward, spleno-SMV anastomosis is necessary instead of spleno-IMV anastomosis.  相似文献   
59.
AIM:To test the hypothesis that the shape and length of Barrett‘s epithelium are associated with prevalence of erosive esophagitis.METHODS:A total study population comprised 869 patients who underwent endoscopy during a health checkup at our hospital.The presence and extent of Barrett‘s epithelium were diagnosed based on the Prague C & M Criteria.We originally classified cases of Barrett‘s epithelium into two types based on its shape,namely,flamelike and lotus-like Barrett‘s epithelium,and into two groups b...  相似文献   
60.
Staphylococcal enterotoxins (SEs) are a common causative agent of food poisoning. Recently, many new SE-like (SEl) toxins have been reported, although the role of SEls in food poisoning remains unclear. In this study, the emetic potentials of SElK, SElL, SElM, SElN, SElO, SElP, and SElQ were assessed using a monkey-feeding assay. All the SEls that were tested induced emetic reactions in monkeys at a dose of 100 μg/kg, although the numbers of affected monkeys were significantly smaller than the numbers that were affected after consuming SEA or SEB. This result suggests that these new SEs may play some role in staphylococcal food poisoning.  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