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   863篇
  免费   55篇
  国内免费   59篇
儿科学   46篇
妇产科学   17篇
基础医学   46篇
口腔科学   17篇
临床医学   137篇
内科学   243篇
皮肤病学   19篇
神经病学   20篇
特种医学   239篇
外科学   46篇
综合类   48篇
一般理论   1篇
预防医学   28篇
眼科学   9篇
药学   33篇
中国医学   2篇
肿瘤学   26篇
  2022年   7篇
  2021年   13篇
  2020年   9篇
  2019年   5篇
  2018年   14篇
  2017年   6篇
  2016年   11篇
  2015年   26篇
  2014年   16篇
  2013年   26篇
  2012年   18篇
  2011年   19篇
  2010年   22篇
  2009年   23篇
  2008年   18篇
  2007年   52篇
  2006年   14篇
  2005年   20篇
  2004年   17篇
  2003年   9篇
  2002年   10篇
  2001年   13篇
  2000年   6篇
  1999年   11篇
  1998年   51篇
  1997年   35篇
  1996年   59篇
  1995年   44篇
  1994年   40篇
  1993年   49篇
  1992年   9篇
  1991年   10篇
  1990年   19篇
  1989年   27篇
  1988年   33篇
  1987年   34篇
  1986年   25篇
  1985年   29篇
  1984年   16篇
  1983年   10篇
  1982年   12篇
  1981年   22篇
  1980年   19篇
  1979年   6篇
  1978年   9篇
  1977年   15篇
  1976年   7篇
  1975年   9篇
  1970年   1篇
  1963年   1篇
排序方式: 共有977条查询结果,搜索用时 15 毫秒
71.
Chronic prostatitis is a common disease of unclear etiology and has no specific treatment. Mice deficient in the expression of the autoimmune regulator (Aire) gene, which are defective in thymic expression of self antigens and central tolerance, develop spontaneous prostatitis. In this study, we found that Aire-deficient mice developed spontaneous B and T cell immune responses to a prostate autoantigen, seminal vesicle secretory protein 2 (SVS2), which we believe to be novel. We show that thymic expression of this self antigen was Aire dependent. Moreover, prostatitis was induced in WT mice through immunization with SVS2, demonstrating that immunity to SVS2 was sufficient to induce prostatitis. The clinical relevance of this antigen was highlighted by our observation that patients with chronic prostatitis possessed specific autoantibodies against the human SVS2-like seminal vesicle protein semenogelin. These results provide direct evidence that spontaneous chronic prostatitis is an autoimmune disease and is regulated by both central and peripheral tolerance. Moreover, SVS2 and semenogelin are among the relevant autoantigens in mice and humans, respectively.  相似文献   
72.
The depth of myometrial invasion by endometrial carcinoma was evaluated using real-time sonography (US) in 20 patients with histologically proved adenocarcinoma of the endometrium. In 14 of 20 (70%) cases, US-based estimation of the depth of myometrial invasion was within 10% of the actual measurement in the gross specimen. The US-based estimation of tumor invasion was low in seven patients, high in four patients, and agreed with pathologic findings (+/- 5%) in nine patients. In four patients with polypoid intraluminal extension of tumor, a deeply invasive tumor was suspected on US but was not found on pathologic examination. In 12 superficially invasive tumors, the continuity of the demarcating subendometrial halo was intact in nine and incomplete in three. In six patients with deeply invasive tumors, this zone was partially disrupted in four, totally disrupted in one, and intact in one. Errors of estimation of the depth of myometrial invasion on US most frequently occurred when a tumor had a significant intraluminal polypoid extension. Demonstration of a subendometrial halo usually indicated superficial invasion, whereas the absence of a halo was frequently associated with deep invasion.  相似文献   
73.
74.
Insertion of a screw biopsy stylet into a thin-walled biopsy needle greatly enhances detection of the needle during ultrasound-guided percutaneous biopsy. This technique is helpful when precise needle-tip localization is needed for biopsies of small lesions.  相似文献   
75.
In this study, mycoplasma were enumerated in the gingival crevicular fluid (GCF) of gingivitis and periodontitis patients. GCF samples were obtained from the mesial (approximal) gingival crevice or periodontal pocket of the maxillary right first permanent molar. Samples were cultured anaerobically on a medium selective for mycoplasmas as well as on a non-selective medium to obtain a total anaerobic count. Mycoplasmas were present in the GCF of both gingivitis and periodontitis patients, but a greater % was obtained from the GCF of patients with periodontitis. The proportions of mycoplasma appeared to be independent of the disease activity as expressed by bleeding on probing (PBI), but to be related to probable pocket depth, as shown by the higher %s in periodontitis than gingivitis for a given PBI. On the basis of an increased proportion in relation to disease severity, mycoplasmas would therefore appear to be amongst those micro-organisms associated with CIPD.  相似文献   
76.
77.
Gurney  JW; Bates  FT 《Radiology》1989,173(1):27-31
A rare pulmonary manifestation of the acquired immunodeficiency syndrome or intravenous (IV) drug abuse is upper lobe cystic disease--pneumatoceles in Pneumocystis carinii pneumonia (PCP) and bullous emphysema in IV drug abuse. Because these disorders overlap, the radiographic findings in 56 patients were compared. During a 12-month period, 16 patients less than 40 years of age were found to have bullous emphysema; the 10 who were IV drug abusers constituted group 1. In the same time period, 40 patients with PCP were encountered; the eight (20%) who had or developed pneumatoceles constituted group 2. In both groups, the conventional radiographic manifestations of upper lobe cystic disease were similar. Eight patients underwent computed tomography of the chest. In five patients with bullous disease, the distribution of the bullous lesions was peripheral, with sparing of the central portions of the lungs. In contrast, PCP pneumatoceles in three patients were dispersed throughout the lung parenchyma.  相似文献   
78.
79.
80.
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