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   23304篇
  免费   1782篇
  国内免费   54篇
耳鼻咽喉   225篇
儿科学   953篇
妇产科学   589篇
基础医学   3155篇
口腔科学   714篇
临床医学   2662篇
内科学   4492篇
皮肤病学   356篇
神经病学   1828篇
特种医学   1108篇
外科学   3138篇
综合类   403篇
一般理论   43篇
预防医学   2170篇
眼科学   355篇
药学   1420篇
  2篇
中国医学   16篇
肿瘤学   1511篇
  2021年   332篇
  2020年   237篇
  2019年   369篇
  2018年   409篇
  2017年   332篇
  2016年   342篇
  2015年   443篇
  2014年   596篇
  2013年   797篇
  2012年   1133篇
  2011年   1224篇
  2010年   696篇
  2009年   595篇
  2008年   1097篇
  2007年   1201篇
  2006年   1112篇
  2005年   1104篇
  2004年   963篇
  2003年   965篇
  2002年   826篇
  2001年   649篇
  2000年   630篇
  1999年   539篇
  1998年   312篇
  1997年   276篇
  1996年   263篇
  1995年   266篇
  1994年   231篇
  1993年   218篇
  1992年   475篇
  1991年   477篇
  1990年   447篇
  1989年   471篇
  1988年   428篇
  1987年   378篇
  1986年   322篇
  1985年   394篇
  1984年   296篇
  1983年   272篇
  1982年   174篇
  1981年   141篇
  1979年   214篇
  1978年   195篇
  1977年   161篇
  1976年   155篇
  1975年   165篇
  1974年   158篇
  1973年   197篇
  1972年   159篇
  1971年   142篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
62.
BACKGROUND: Diagnosis of atopic dermatitis (AD) depends on clinical features because no definitive diagnostic test exists. Criteria proposed by Hanifin and Rajka (Acta Derm Venereol (Stockh) 1980; Suppl 92: 44-47) were acceptable for hospital-based studies but were found not to be suitable for field studies. A UK working party formulated clinical diagnostic criteria that could be used in both hospital and epidemiological settings. Validation studies of the criteria showed widely variable results, probably due to different clinical settings and ethnicity. AIM AND OBJECTIVE: This study was undertaken to validate Hanifin and Rajka's criteria and to assess the comparative efficacy of their criteria and the UK working party's diagnostic criteria in the diagnosis of AD in a hospital setting in North India. SUBJECTS AND METHODS: This study serially included 101 patients with AD and 48 controls of paediatric age group. The study period was from July 2003 to December 2004. RESULTS: Hanifin and Rajka's criteria (sensitivity 96%, specificity 93.75%, positive predictive value 97% (PPV) and negative predictive value (NPV) 91.84%) had a statistical advantage over the UK working party's diagnostic criteria (sensitivity 86%, specificity 95.83%, PPV 97.75% and NPV 76.67%), with a P-value < 0.005.  相似文献   
63.
Background Sympathectomy is the treatment of choice for primary hyperhidrosis. One curious occurrence that is difficult to explain from an anatomophysiological point of view in cases of video-assisted thoracoscopic sympathectomy (VATS) for the treatment of palmar hyperhidrosis (PH) is the observed improvement in plantar hyperhidrosis (PLH). Nevertheless, current reports on VATS rarely describe the effect on PLH or just give superficial data. The aim of this study was to prospectively investigate, how surgery affects PLH in patients with PH and PLH over one-year period. Methods From May 2003 to January 2004, 70 consecutive patients with combined PH and PLH underwent VATS at the T2, T3, or T4 ganglion level (47 women and 23 men, with mean age of 23 years). Results Immediately after the operation, all the patients said they were free from PH episodes, except for two patients (2.8%) who suffered from continued PH. Compensatory hyperhidrosis (CH) of various degrees was observed in 58 (90.6%) patients after one year. Only 13 (20.3%) suffered from severe CH. There was a great initial improvement in PLH in 50% of the cases, followed by progressive regression, such that only 23.4% still presented that improvement after one year. The number of cases without overall improvement increased progressively (from 17.1% to 37.5%) and the numbers with slight improvement remained stable (32.9–39.1%). Of the 24 patients with no improvement after one year, 6 patients graded plantar sweating worse. Conclusion Patients with PH and PLH who undergo VATS to treat their PH present a good initial improvement in PLH that reduces to a lower level of improvement after the one-year period.  相似文献   
64.
65.
66.
SUMMARY Impotence is a common symptom which can cause considerable distress to both the sufferer and his partner. The use of pharmacotherapy to improve erectile function will continue to increase as safe and effective drugs are developed. However, restoring erectile function should not be the only treatment objective. It is also essential to address personal and emotional factors in the sufferer, conflicts in his relationship with his partner, and sexual problems in his partner, all of which may be instrumental in causing or maintaining the presenting impotence. We advocate a combined approach with appropriate medical treatment and sex and couple therapy  相似文献   
67.
A 7-cm anterior mediastinal tumor in an 80-year-old woman was found by light and electron microscopy to be a neuroblastoma. Immunoreactivity for neuron-specific enolase, synaptophysin, and chromogranin supported the diagnosis. Neuroblastoma is an uncommon tumor in adults and we are not aware of a previous report of such a tumor in a patient of this age.  相似文献   
68.
Single breath-holding gradient echo techniques fast imaging with steady-state free precession (FISP) and fast low angle shot (FLASH) images were evaluated in the study of the abdomen in 16 patients (13 liver, two kidney, and one pancreas examinations). Gradient echo images were compared retrospectively with conventional spin echo images for image quality (depiction of pathology and representation of anatomic detail), and contrast characteristics were evaluated. All lesions were shown on gradient echo images, and in three of 16 cases gradient echo images were more diagnostic than spin echo images. On both FISP and FLASH images, most hepatic metastases were hyperintense relative to normal liver. The predicted flip angles for maximal contrast for the liver were modeled from signal intensity equations for FISP and FLASH and yielded predicted flip angles of approximately 40-55 degrees for FISP and 15-25 degrees for FLASH. Peak signal-to-noise ratio in liver of normal volunteers occurred at approximately 30 degrees for both FISP and FLASH. Single breath-holding gradient echo images are useful in the evaluation of abdominal structures and this study provides a framework for future work.  相似文献   
69.
70.
Designing behavior change programs and evaluating their effects on patient care has been a persistent challenge in research on continuing medical education. The challenge becomes even more complex when we aim to change behaviors that are interactive and highly influenced by the formal and informal institutional context. The authors describe an interdisciplinary continuing education program in bioethics that is designed to effect just such behaviors. The program aims to help hospital and long-term care facilities improve their ability to resolve the ethical dilemmas inherent in terminal care decisions. Targeted to interdisciplinary groups of physicians, nurses, social workers, pastoral counselors, and administrators, Decisions Near the End of Life will provide strategies and tools for examining institutional policies and team practices as well as more traditional information, education, and skill building. The authors describe the program's rationale and design, and raise questions about the potential for developing interdisciplinary, action-oriented CME on other topics.  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