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   1529篇
  免费   61篇
  国内免费   148篇
耳鼻咽喉   1篇
儿科学   60篇
妇产科学   84篇
基础医学   130篇
口腔科学   31篇
临床医学   190篇
内科学   496篇
皮肤病学   39篇
神经病学   53篇
特种医学   307篇
外科学   78篇
综合类   24篇
预防医学   41篇
眼科学   21篇
药学   126篇
  1篇
中国医学   1篇
肿瘤学   55篇
  2023年   6篇
  2021年   7篇
  2020年   5篇
  2019年   17篇
  2018年   15篇
  2017年   9篇
  2016年   17篇
  2015年   16篇
  2014年   24篇
  2013年   49篇
  2012年   44篇
  2011年   61篇
  2010年   48篇
  2009年   66篇
  2008年   56篇
  2007年   142篇
  2006年   41篇
  2005年   48篇
  2004年   24篇
  2003年   11篇
  2002年   25篇
  2001年   32篇
  2000年   33篇
  1999年   35篇
  1998年   88篇
  1997年   84篇
  1996年   82篇
  1995年   67篇
  1994年   49篇
  1993年   56篇
  1992年   19篇
  1991年   29篇
  1990年   19篇
  1989年   65篇
  1988年   39篇
  1987年   42篇
  1986年   31篇
  1985年   28篇
  1984年   20篇
  1983年   15篇
  1982年   27篇
  1981年   20篇
  1980年   16篇
  1979年   13篇
  1978年   11篇
  1977年   19篇
  1976年   30篇
  1975年   17篇
  1969年   4篇
  1966年   3篇
排序方式: 共有1738条查询结果,搜索用时 218 毫秒
21.
A 15 year old boy with autoimmune polyendocrinopathy-candidosis-ectodermal dystrophy syndrome suffered recurrent episodes of severe intractable diarrhoea, steatorrhoea, and hypocalcaemia. The only treatment modality, which controlled the malabsorption syndrome, was immunosuppression with intravenous high dose methylprednisolone and oral methotrexate maintenance therapy.  相似文献   
22.
A 54-year-old man was treated with weekly 24-h infusion of high-dose 5-fluorouracil (2600 mg/m2) and leucovorin (100 mg/m2) for metastatic colon cancer. At first, he tolerated the treatment well and no significant toxicity was identified. After a total of eight courses of treatment, a stable disease was observed, but mild shortness of breath was found on occasion. The patient had no previous history of cardiac disease and the heart performance assessed by left ventricular ejection fraction before treatment was normal. Unfortunately, acute pulmonary edema with lethal cardiogenic shock occurred during the ninth course of treatment, in spite of intensive medical treatment. The chest X-ray showed extreme cardiomegaly. Repeated assessment of his heart function by echocardiogram and ventricular ejection fraction revealed a very poor cardiac performance. Toxic cardiogenic shock during weekly 24-h infusion of high-dose 5-fluorouracil and leucovorin is extremely rare. To the best of our knowledge, no case has been reported in the English literature. We report a case and the relevant literature about the incidence, clinical picture and possible pathophysiology on 5-fluorouracil-related cardioxicity is reviewed.   相似文献   
23.
Adipositas     
  相似文献   
24.
Background. Routine lateral turning of patients has become an accepted standard of care to prevent complications of immobility. The haemodynamic and oxygenation effects for patients in both lateral positions (45°) are still a matter of debate. We aimed to study the effect of these positions on blood pressure, heart rate and oxygenation in a general intensive care population. Design. Observational study. Method. Twenty stable intensive care unit patients had intra‐arterial blood pressure recordings in the supine and lateral positions with the correction of hydrostatic height compared with a fixed reference point (phlebostatic level). A multilevel model was used to analyse the data. Results. Mean arterial pressure readings in the lateral positions were, on average, 5 mmHg higher than in the supine position (p < 0·001). There were no significant differences between mean arterial pressure recordings in the left and right lateral position (p = 1·0). No important differences in oxygenation and heart rate were observed. After correction for covariates, the effects persisted. Conclusion. Our study demonstrated an increase, albeit small, in blood pressure in the lateral positions. No major differences between the left and right lateral position were found. No important differences in oxygenation and heart rate were observed. Relevance to clinical practice. Turning haemodynamically stable patients in the intensive care unit has no important effects on blood pressure measurements when continuous hydrostatic height correction is applied.  相似文献   
25.
26.
In systemic sclerosis, microvascular injury often precedes the development of fibrosis. Whereas the development of digital ulcers and skin fibrosis causes high morbidity, the affection of internal organs, in particular complications such as interstitial lung disease and pulmonary (arterial) hypertension, account for the high disease-associated mortality of these patients. Vascular animal models of systemic sclerosis are of utmost importance to study pathophysiological aspects, to identify molecular key players, and to perform interventional proof of concept-studies. So far, animal models of systemic sclerosis have mainly reflected the pro-fibrotic features of the human disease. The Fra-2 (Fos-related antigen-2) transgenic mouse model simultaneously displays both pro-fibrotic and vascular characteristics of human systemic sclerosis.  相似文献   
27.
Background The clinical characteristics of vitiligo in children and adolescents with an emphasis on thyroid dysfunction have only been reported in a few studies. Objective The purpose of this study was to examine the characteristics of children and adolescents with vitiligo and compare the incidence of thyroid dysfunction between them and controls without vitiligo at the same age. Methods A retrospective analysis of 324 Korean children and adolescents with vitiligo was performed. The results of thyroid function screening tests in them (n = 254) were compared with controls (n = 122). Results Of the total 324 children and adolescents with vitiligo, vitiligo vulgaris was the most common type (42.3%) and the most commonly involved site was the face (54.6%). A total of 15 of 254 (5.9%) patients screened for thyroid function were diagnosed with thyroid disease (four had Hashimoto’s thyroiditis; two, Graves’ disease; seven, subclinical hypothyroidism; and two, subclinical hyperthyroidism). None of the 50 patients with segmental vitiligo showed any thyroid dysfunction (P = 0.047). There was no significant difference in the incidence of thyroid disease between children and adolescents with vitiligo and the control group, in which seven of 122 (5.7%) showed thyroid dysfunction. Conclusion In this study, we demonstrated the characteristics of children and adolescents with vitiligo and also observed no significant difference in the incidence of thyroid disease between children and adolescents with vitiligo and the control group.  相似文献   
28.
A protein S deficient family presenting a variant protein S molecule in plasma and platelets is described. The propositus, age 20, and two brothers suffered from venous thrombotic disease. The propositus, the only family member studied while taking oral anticoagulants, had a protein S antigen (ag) level of 17% and undetectable activity. As demonstrated by immunoblotting both the propositus and one clinically affected brother (42% ag, 7% activity) presented variant protein S molecules of 65,000 molecular weight (mol wt) while the other clinically affected brother (64% ag, 11% activity) had only protein S with normal electrophoretic mobility of 70,000 mol wt. The mother had normal protein S levels (93% ag, 100% activity) but had both normal and variant protein S molecules and based on her functional protein S data a normal anticoagulant activity of the variant molecule is suggested. One asymptomatic but protein S deficient sister (68% ag, 9% activity) as well as the asymptomatic protein S deficient father (59% ag, 10% activity) had only protein S molecules of 70,000 mol wt. The variant protein S bound to C4b-binding protein in plasma, and differed from normal protein S in carbohydrate content. Platelets of each family member contained the same immunoblotting pattern of normal and variant protein S forms as found in plasma, consistent with the hypothesis that protein S gene expression involves codominant expression of two alleles that is similar in cells that control the synthesis of both platelet and plasma forms of protein S.  相似文献   
29.
In four healthy volunteers, we analyzed in detail the immediate in vivo effects on circulating neutrophils of subcutaneous administration of 300 micrograms of granulocyte colony-stimulating factor (G-CSF). Neutrophil activation was assessed by measurement of degranulation. Mobilization of secretory vesicles was shown by a decrease in leukocyte alkaline phosphatase content of the circulating neutrophils. Furthermore, shortly postinjection, Fc gamma RIII was found to be upregulated from an intracellular pool that we identified by immunoelectron microscopy as secretory vesicles. Intravascular release of specific granules was shown by increased plasma levels of lactoferrin and by upregulation of the expression of CD66b and CD11b on circulating neutrophils. Moreover, measurement of fourfold elevated plasma levels of elastase, bound to its physiologic inhibitor alpha 1- antitrypsin, indicated mobilization of azurophil granules. However, no expression of CD63, a marker of azurophil granules, was observed on circulating neutrophils. G-CSF--induced mobilization of secretory vesicles and specific granules could be mimicked in whole blood cultures in vitro, in contrast to release of azurophil granules. Therefore, we postulate that the most activated neutrophils leave the circulation, as observed shortly postinjection, and undergo subsequent stimulation in the endothelial microenvironment, resulting in mobilization of azurophil granules. Our data demonstrate that G-CSF should be regarded as a potent immediate activator of neutrophils in vivo.  相似文献   
30.
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