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   10287篇
  免费   468篇
  国内免费   30篇
耳鼻咽喉   154篇
儿科学   144篇
妇产科学   112篇
基础医学   1030篇
口腔科学   328篇
临床医学   599篇
内科学   2339篇
皮肤病学   354篇
神经病学   822篇
特种医学   417篇
外科学   1580篇
综合类   40篇
一般理论   1篇
预防医学   365篇
眼科学   142篇
药学   923篇
中国医学   11篇
肿瘤学   1424篇
  2023年   64篇
  2022年   116篇
  2021年   175篇
  2020年   112篇
  2019年   150篇
  2018年   199篇
  2017年   165篇
  2016年   163篇
  2015年   180篇
  2014年   234篇
  2013年   259篇
  2012年   436篇
  2011年   493篇
  2010年   269篇
  2009年   215篇
  2008年   416篇
  2007年   427篇
  2006年   452篇
  2005年   459篇
  2004年   433篇
  2003年   392篇
  2002年   405篇
  2001年   409篇
  2000年   402篇
  1999年   383篇
  1998年   132篇
  1997年   97篇
  1996年   94篇
  1995年   85篇
  1994年   75篇
  1993年   58篇
  1992年   260篇
  1991年   249篇
  1990年   257篇
  1989年   254篇
  1988年   214篇
  1987年   208篇
  1986年   167篇
  1985年   180篇
  1984年   126篇
  1983年   108篇
  1982年   49篇
  1979年   87篇
  1978年   57篇
  1977年   56篇
  1974年   53篇
  1971年   49篇
  1969年   46篇
  1967年   46篇
  1966年   43篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
Intraosseous ganglia of the glenoid are rare, and their etiology is unknown. This report describes a case of an intraosseous ganglion about to cause fracture of the glenoid. The patient was a 61-year-old woman with a painful left shoulder with a limited range of motion. Her symptoms did not improve after non-operative treatment. Arthroscopic examination showed a cartilage defect and erosion in the posteroinferior portion of the glenoid, behind which computed tomography (CT) showed a cystic lesion of the glenoid. There was no communication between the cyst and the joint space. The patient was treated by curettage and an autogenous cancellous bone graft from the iliac crest. Two years after the operation, the patient was almost free from pain, and CT showed good integration of the bone graft.  相似文献   
12.
A new diterpene antitumor antibiotic, myrocin C, has been isolated from the culture filtrate of a soil fungus, Myrothecium verrucaria strain No. 55. The antibiotic was effective against Gram-positive bacteria, fungi and yeasts, and prolonged the life span of mice bearing Ehrlich ascites carcinoma.  相似文献   
13.
We describe a case of elastosis perforans serpiginosa with additional findings of degenerative skin changes. A 20-year-old man with hepatolenticular degeneration, under prolonged treatment with D-penicillamine, presented with a circular or serpiginous arrangement of nuchal papules. Histopathologically, transepidermal channels were accompanied by granulomatous reactions, with several giant cells engulfing elastic fibers. In addition to these findings of a typical elastosis perforans serpiginosa, we observed scar-like skin changes inside the circular arrangement of the papules. At the scar-like tissue, we found electron-microscopical evidence of randomly aggregated thin collagen fibers with no tendency toward systemic combined bundle formation, which is a characteristic feature of normal collagen fiber formation. Pseudoxanthoma-elasticum-like changes were observed on his neck. On his axillae and groin, slight skin thickening and wrinkling were detected. The diagnosis of elastosis perforans serpiginosa does not represent all of the manifestations or the pathological background described above. The skin manifestations described here represent not only an elastosis but also a total degenerative dermatosis with over-healed collagenosis. Thus, those dermatoses should be summarized as one entity, penicillamine-induced degenerative dermatosis. After considering the pathogenic background and clinical similarities, we further propose to simplify the penicillamine-induced skin manifestations to three categories: acute sensitivity reactions, bullous dermatoses, and degenerative dermatoses.  相似文献   
14.
15.
We have previously shown that interleukin (IL)-1beta and tumour necrosis factor (TNF)-alpha mRNA levels in rat alveolar macrophages are increased in by endotoxin (lipopolysaccharide; LPS)- stimulation and further enhanced by culturing with low-Mg2+ medium. We have now investigated the mechanisms of underlying this enhancement by using some specific signal transduction inhibitors. The enhanced elevation of both mRNAs levels was suppressed by pretreatment with TMB-8 (which inhibits calcium release from the endoplasmic reticulum) or dexamethasone (which inhibits nuclear factor [NF]-kappaB and activator protein [AP]-1), but not with verapamil or nifedipine (which inhibits calcium channels). The enhancment of IL-1beta, but not TNF-alpha mRNA levels, was suppressed by pretreatment with W-7 (which inhibits calmodulin), whereas the enhancement of TNF-alpha mRNA levels was suppressed by pretreatment with U73122 (which inhibits phospholipase C). Curcumin (an inhibitor of AP-1), suppressed the increases in both mRNAs induced by low-Mg2+ medium alone, but had no suppressive effect on the levels of either mRNA after LPS-stimulation in low-Mg2+ medium. Pyrrolidine dithiocarbamate (an inhibitor of NF-kappaB) prevented the elevation of TNF-alpha mRNA levels induced by low-Mg2+ medium without LPS-stimulation, but had no suppressive effect on IL-1beta mRNA levels. From these results, we conclude that the enhanced elevation of IL-1beta and TNF-alpha mRNA levels seen in LPS-stimulated alveolar macrophages in low-Mg2+ medium occurs partly via the same, and partly via different, signaling pathways.  相似文献   
16.
Furosemide is a potent diuretic that affects water transfer across the respiratory epithelium, which is closely related to the transepithelial potential difference (PD). Water is a critical factor that determines mucus transport; an important lung defence mechanism that removes particles and microorganisms from the respiratory system. The aim of the present study was to investigate the acute effects of furosemide and hypovolaemia on tracheal PD and mucus properties. A total of 36 male mixed-breed dogs were submitted to anaesthesia, mechanical ventilation and haemodynamic monitoring. They were randomly assigned to three groups consisting of: a control group, a furosemide (40 mg i.v.) + hypovolaemia group, and a furosemide (40 mg i.v.) + volume replacement group. Tracheal PD and mucus samples were collected at time 0, 1 and 2 h after intervention. Mucus properties were analysed by means of a magnetic microrheometer and in vitro mucociliary transportability on the frog palate. Compared to controls, furosemide decreased PD to intermediate values, and only significantly when associated with hypovolaemia (-13+/-5 and -8+/-2 mV, time 0 and 2 h, respectively). In addition to the direct effect of furosemide, these results indicate that hypovolaemia also affects ion transport in the tracheal membrane. Furosemide and hypovolemia have no acute effects on respiratory mucus properties.  相似文献   
17.
18.
19.
A 69-year-old man was admitted to hospital because of sustainedventricular tachycardia with right bundle branch block morphology.After abolition of ventricular tachycardia, an electrocardiogramshowed atrial fibrillation, complete right bundle  相似文献   
20.
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