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   1433篇
  免费   80篇
  国内免费   1篇
耳鼻咽喉   8篇
儿科学   82篇
妇产科学   72篇
基础医学   192篇
口腔科学   29篇
临床医学   119篇
内科学   367篇
皮肤病学   41篇
神经病学   165篇
特种医学   24篇
外国民族医学   1篇
外科学   202篇
综合类   10篇
一般理论   2篇
预防医学   82篇
眼科学   13篇
药学   38篇
中国医学   1篇
肿瘤学   66篇
  2022年   14篇
  2021年   22篇
  2020年   16篇
  2019年   28篇
  2018年   28篇
  2017年   31篇
  2016年   23篇
  2015年   29篇
  2014年   51篇
  2013年   58篇
  2012年   88篇
  2011年   102篇
  2010年   47篇
  2009年   45篇
  2008年   58篇
  2007年   86篇
  2006年   86篇
  2005年   93篇
  2004年   78篇
  2003年   69篇
  2002年   61篇
  2001年   29篇
  2000年   26篇
  1999年   20篇
  1998年   17篇
  1997年   15篇
  1996年   7篇
  1995年   7篇
  1994年   10篇
  1992年   10篇
  1991年   15篇
  1990年   17篇
  1989年   15篇
  1988年   15篇
  1987年   14篇
  1986年   17篇
  1984年   11篇
  1983年   10篇
  1981年   5篇
  1979年   10篇
  1978年   9篇
  1977年   10篇
  1975年   9篇
  1974年   13篇
  1973年   10篇
  1971年   9篇
  1970年   8篇
  1969年   5篇
  1966年   5篇
  1930年   4篇
排序方式: 共有1514条查询结果,搜索用时 15 毫秒
1.
2.
Painful calcinosis appeared at the wrist of an eight-year-old girl with lead poisoning. Careful history revealed that calcification occurred at the site of previous extravasation of calcium disodium edetate (EDTA) used in chelation therapy. Light microscopic, ultrastructural, electron activation, and X-ray diffraction studies demonstrated apatites with some suggestion of an admixture of octacalcium phosphate.  相似文献   
3.
A retrospective study on the value of magnetic resonance imaging (MRI) in replacing contrast studies of the lumbar spine has been undertaken. Studying pre- and postoperative conditions, the authors attempted to answer the question, Will MRI replace myelography? In this retrospective study, comparison is made in 20 patients between MRI and myelography and with 12 intra-operative findings. The overall impression was that MRI is equally sensitive as the invasive myelogram in diagnosing both protruded lumbar discs and postoperative fibrosis. The practical conclusion was an almost complete abandonment of myelography.  相似文献   
4.
5.
Alexithymia was measured in non-treatment seeking, community-dwelling Holocaust survivors using the Toronto Alexithymia Scale—Twenty Item Version (TAS-20). Scores of survivors with (n = 30) and without (n = 26) posttraumatic stress disorder (PTSD) were compared, and associations among alexithymia, severity of trauma, and severity of PTSD symptoms were determined. Survivors with PTSD had significantly higher scores on the TAS-20 compared to survivors without PTSD. TAS-20 scores were significantly associated with severity of PTSD symptoms, but not with severity of trauma. This study adds to our knowledge of the relationship between alexithymia and trauma by demonstrating that this characteristic is related to the presence of posttraumatic symptoms and not simply exposure to trauma.  相似文献   
6.
We report a case of erythrodermic type of bullous pemphigoid which is a rare variant of bullous pemphigoid. Our patient had a peculiar clinical presentation with bullae, erosions and extensive erythrodermic areas, and distinct direct immunofluorescent findings which included linear IgG and C3 deposits in the basement membrane and also IgG in the intercellular spaces. Very high levels of serum IgE were also detected in our patient.  相似文献   
7.
Empirical studies have questioned the validity of the Faces subtest from the WMS-III for detecting impairment in visual memory, particularly among the elderly. A recent examination of the test norms revealed a significant age related floor effect already emerging on Faces I (immediate recall), implying excessive difficulty in the acquisition phase among unimpaired older adults. The current study compared the concurrent validity of the Faces subtest with an alternative measure between 16 Alzheimer's patients and 16 controls. The alternative measure was designed to facilitate acquisition by reducing the sequence of item presentation. Other changes aimed at increasing the retrieval challenge, decreasing error due to guessing and standardizing the administration. Analyses converged to indicate that the alternative measure provided a considerably greater differentiation than the Faces subtest between Alzheimer's patients and controls. Steps for revising the Faces subtest are discussed.  相似文献   
8.
  lia Weisz  Gy  rgy   d  m 《Neuropsychologia》1993,31(12):1299-1306
This study investigated the relationship between the direction of lateral eye shifts evoked by bilateral visual stimulation, on the one hand, and verbal vs visuospatial performance, on the other. In males a negative correlation was found between verbal relative to spatial accuracy and the ratio of leftward eye movements. No such relationship was found in females. Additionally, in males body mass index was smaller for those who displayed a greater ratio of leftward eye movements. It was concluded that visually evoked lateral eye shifts might reflect hemispheric preference, similarly as lateral eye movements obtained during the widely used questioning procedure. However, the procedure used in this study for evoking lateral eye shifts seems to be free of some methodological problems of the traditional procedure and is more easy to standardize.  相似文献   
9.
The purpose of this study was to determine the suitability of MRI to accurately detect radiofrequency (RF) thermoablative lesions created under MR guidance. In vivo RF lesions were created in the livers of six New Zealand White rabbits using a 2-mm-diameter titanium alloy RF electrode with a 20-mm exposed tip and a 50-W RF generator. This was performed using a 0.2T clinical C-arm MR imager for guidance and monitoring. Each animal was sacrificed and gross evaluation was performed. Histologic correlation was performed on the first two animals. The MR-compatible RF electrode was easily identified on rapid gradient-echo images used to guide electrode placement. A single lesion was created in each rabbit liver. Lesions ranged from approximately 10 to 17 mm in diameter (mean, 13.5 mm). T2-weighted and short T1 inversion recovery (STIR) images demonstrated lesions ranging in diameter from 12 to 18 mm (mean, 14.6 mm). Lesion dimensions determined from images closely correlated with those determined at gross examination with the discrepancy never exceeding 2 mm, for an r2 value of .87. MRI performed at the time of MR-guided RF ablation accurately demonstrated created lesions. This modality may provide a new option for the treatment of local and regional neoplastic disease.  相似文献   
10.
Pathogen-related oral spirochetes from dental plaque are invasive.   总被引:6,自引:7,他引:6       下载免费PDF全文
Spirochetes that share pathogen-restricted antigens with Treponema pallidum subsp. pallidum have been identified in dental plaque and diseased gingival tissues, but it is not known whether these spirochetes possess virulence characteristics. In this study, plaque spirochetes were able to transmigrate a tissue barrier in vitro and were identified on the other side by using monoclonal antibodies specific for pathogen-restricted determinants from T. pallidum subsp. pallidum. This invasive capability is shared with T. pallidum subsp. pallidum, but cultured oral and intestinal treponemes did not perforate the tissue barrier. Cocultures indicated that invasive treponemes do not create opportunities for cultivable oral treponemes to cross the barrier. These findings indicate that gingival tissues may be a port of entry for previously unrecognized invasive spirochetes in humans.  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