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   1454篇
  免费   149篇
  国内免费   7篇
耳鼻咽喉   7篇
儿科学   79篇
妇产科学   30篇
基础医学   141篇
口腔科学   38篇
临床医学   141篇
内科学   268篇
皮肤病学   12篇
神经病学   64篇
特种医学   150篇
外科学   96篇
综合类   63篇
预防医学   111篇
眼科学   210篇
药学   101篇
中国医学   4篇
肿瘤学   95篇
  2023年   13篇
  2022年   17篇
  2021年   45篇
  2020年   28篇
  2019年   33篇
  2018年   48篇
  2017年   29篇
  2016年   39篇
  2015年   54篇
  2014年   80篇
  2013年   83篇
  2012年   83篇
  2011年   88篇
  2010年   48篇
  2009年   52篇
  2008年   90篇
  2007年   71篇
  2006年   71篇
  2005年   48篇
  2004年   42篇
  2003年   32篇
  2002年   39篇
  2001年   19篇
  2000年   9篇
  1999年   26篇
  1998年   43篇
  1997年   36篇
  1996年   41篇
  1995年   33篇
  1994年   31篇
  1993年   25篇
  1992年   12篇
  1991年   11篇
  1990年   8篇
  1989年   15篇
  1988年   23篇
  1987年   20篇
  1986年   20篇
  1985年   19篇
  1984年   13篇
  1983年   16篇
  1982年   7篇
  1981年   11篇
  1980年   5篇
  1979年   5篇
  1978年   4篇
  1977年   7篇
  1976年   7篇
  1975年   4篇
  1972年   3篇
排序方式: 共有1610条查询结果,搜索用时 15 毫秒
101.
Two cases of epidermal cyst of the breast, a rare benign condition, were detected during a 3-year period in a mammographic screening programme, from 57 954 screening examinations. It is not uncommon for epidermal cysts to be initially misdiagnosed. The mammographic, ultrasound and histological features are presented. It is recommended that these lesions be resected because they possibly have malignant potential.  相似文献   
102.
The word tracheostomy derived from two greek words meaning ‘I cut the trachea’ has been known for about 3500 yrs. The process has evolved over the years and has undergone revolutionary changes in the methodology, instrumentation and indications. Although tracheostomy is now commonly used the complication rate remains high. In our series it was 48% which is comparable with other series. The purpose of this paper is to discuss the complications of tracheostomy with special attention to their management and prevention.KEY WORDS: Complications, Tracheostomy  相似文献   
103.
104.
线中殖孔绦虫(Mesocestoides lineatus Goeze,1782)人体感染极为少见。我们于吉林省发现一患者并获得完整虫体,对其形态进行了较为详细的观察和描述,澄清了某些书刊中的不正确描述。  相似文献   
105.
Centrilobular emphysema: CT-pathologic correlation   总被引:5,自引:0,他引:5  
Over a 5-year period, 25 patients who had undergone chest computed tomography (CT) died and were autopsied. Their lungs were fixed in the inflated state and were assessed for the presence and severity of centrilobular emphysema (CLE). Three radiologists independently evaluated the CT scans for nonperipheral low-attenuation areas, peripheral low-attenuation areas, pulmonary vascular pruning, pulmonary vascular distortion, and pulmonary density gradient. The CT criterion that best correlated with the presence and severity of CLE was the nonperipheral low-attenuation area. With this CT criterion, lung destruction was correctly identified in 13 of 15 cases. The absence of this criterion resulted in correct identification of eight of ten normal lungs. These preliminary data suggest that CLE can be reliably identified and quantified with current CT scanners.  相似文献   
106.
107.
Fifty-two patients with clinical stage A and B carcinomas of the prostate were imaged by ultrasound (US) transrectally with a 5-MHz linear array transducer and transabdominally with a 3-MHz sector scanner prior to radical prostatectomy. The fresh specimens of 44 prostate glands were scanned in a water bath with a 5-MHz linear array transducer in multiple planes. In all cases, histopathologic correlation was obtained. Prostatic carcinoma presented as an echopenic lesion in 54% of the specimens, as a slightly hypoechoic area in 22%, and could not be identified in 24% because of its isoechoic characteristics. In contrast to many previous reports, no instance of echogenic cancer was observed.  相似文献   
108.
High-resolution magnetic resonance (MR) imaging with a surface coil was utilized to evaluate the normal scrotum. Scrotal contents, spermatic canal, and inguinal regions were visualized within the same field of view. Differences in signal intensity in the testis, epididymis, tunica albuginea, fluid, fat, and spermatic cord allowed for clear delineation of these structures in detail. The high contrast and spatial resolution of MR imaging, coupled with the wide field of view and absence of ionizing radiation, make MR imaging well suited for evaluation of the scrotum.  相似文献   
109.
The diagnostic value of biphasic radiographic examination of the stomach and duodenum was compared with that of fiberoptic endoscopy in a prospective, blinded study of 385 patients with dyspepsia. This investigation was directed at gastric malignancies and peptic ulcers. Methodologically there is no absolute standard for a study of this kind because histologic examination is useful for detection of cancer but inadequate for ulcers. As an alternative, kappa indexes and the sensitivity and specificity, as derived by Hui and Walter, were calculated and compared. For the detection of gastric carcinoma, radiographic and endoscopic findings had almost perfect agreement beyond chance. For gastric ulcers, radiography and endoscopy had substantial agreement, which became perfect if small ulcers (less than 5 mm) were excluded. For duodenal ulcers, radiography had a lower sensitivity than endoscopy; this disagreement disappeared if small ulcers were excluded. Both methods have equal merit; choice of the initial diagnostic procedure will therefore depend on cost, discomfort to the patient, and risk of complications.  相似文献   
110.
Anthropomorphic radiologic phantoms   总被引:1,自引:0,他引:1  
A technique is being developed for the design and fabrication of anthropomorphic phantoms for diagnostic x-ray imaging. Anatomic information extracted from actual patient radiographs is incorporated into the phantoms using computer image processing and computer-assisted machining methods. In this paper, the technique is described as applied to a breast phantom, and preliminary images that closely mimic human anatomy on radiographs are shown.  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