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   2001篇
  免费   96篇
  国内免费   6篇
耳鼻咽喉   19篇
儿科学   151篇
妇产科学   58篇
基础医学   245篇
口腔科学   26篇
临床医学   121篇
内科学   342篇
皮肤病学   43篇
神经病学   117篇
特种医学   122篇
外科学   246篇
综合类   27篇
预防医学   113篇
眼科学   69篇
药学   172篇
中国医学   13篇
肿瘤学   219篇
  2023年   10篇
  2022年   29篇
  2021年   68篇
  2020年   30篇
  2019年   55篇
  2018年   50篇
  2017年   43篇
  2016年   46篇
  2015年   60篇
  2014年   82篇
  2013年   105篇
  2012年   181篇
  2011年   180篇
  2010年   92篇
  2009年   71篇
  2008年   120篇
  2007年   124篇
  2006年   83篇
  2005年   80篇
  2004年   100篇
  2003年   64篇
  2002年   64篇
  2001年   27篇
  2000年   29篇
  1999年   34篇
  1998年   13篇
  1997年   12篇
  1996年   12篇
  1995年   7篇
  1992年   23篇
  1991年   17篇
  1990年   17篇
  1989年   13篇
  1988年   11篇
  1987年   11篇
  1986年   13篇
  1985年   14篇
  1984年   9篇
  1983年   6篇
  1981年   5篇
  1979年   5篇
  1977年   7篇
  1975年   7篇
  1974年   8篇
  1973年   6篇
  1972年   10篇
  1971年   8篇
  1969年   6篇
  1968年   7篇
  1967年   4篇
排序方式: 共有2103条查询结果,搜索用时 15 毫秒
51.
Autism spectrum disorder (ASD) is being identified in an ever-increasing number of countries, including many that are low or middle income (LMIC). Research conducted in these countries requires awareness of unique ethical issues. Drawing on the experience of two organizations that have been involved in conducting and collaborating in ASD research in India, we describe specific considerations in conducting epidemiological, genetic and treatment studies as well as general principles from the field of multinational clinical research as they apply to the conduct of ASD research. We argue that greater attention to ethical concerns will result in quality studies conducted in LMICs that are also of greatest relevance for families and children with ASD.  相似文献   
52.
In this case report we describe a rare tumor--Oncocytic variant of Mucoepidermoid carcinoma of the submandibular salivary gland with a review of the literature. Oncocytic metaplasia in salivary glands is a benign change that is associated with increasing age and also seen in a few salivary gland neoplasms', which include oncocytoma, Warthin's tumor, and the rare, oncocytic carcinoma. Oncocytic differentiation in mucoepidermoid carcinoma (MEC) is uncommon. Only twelve well-documented cases of oncocytic MEC have been reported previously all of which occurred in the parotid gland. To the best of our knowledge this is the first case of oncocytic mucoepidermoid carcinoma involving the submandibular salivary gland. The recognition of this entity is important, since most of the other primary oncocytic lesions of the salivary gland are benign.  相似文献   
53.
54.
The effects of yoga and ayurveda on geriatric depression were evaluated in 69 persons older than 60 who were living in a residential home. Participants were stratified by age and gender and randomly allocated to three groups: Yoga, Ayurveda, or Wait-list Control. The 15-item Geriatric Depression Scale was used to assess depressive symptoms prior to the intervention, and after 3 months and 6 months post-intervention. Participation in one of the three groups lasted 24 weeks. The yoga program (7 hours 30 minutes per week) included physical postures, relaxation techniques, regulated breathing, devotional songs, and lectures. The Ayurveda Group received an herbal preparation twice daily for the whole period. The depression symptom scores of the Yoga Group at both 3 and 6 months decreased significantly, from a group average baseline of 10.6 to 8.1 and 6.7, respectively (p < .001, paired t-test). The other groups showed no change. Hence, an integrated approach of yoga including the mental and philosophical aspects in addition to the physical practices was useful for institutionalized older persons.  相似文献   
55.
Purpose:Vitreoretinal lymphoma (VRL) is the most common intraocular lymphoma (IOL). This can be either primary or secondary to the central nervous system lymphoma. The diagnosis of primary intraocular lymphoma (PIOL) currently relies on clinical diagnosis and cytological analysis of the vitreous or subretinal biopsy. Although most cases are diagnosed without much issue, the limited amount of vitreous fluid, subjectivity in cytological reporting, and special expertise in ocular pathology make the diagnosis challenging. MYD88 L265P mutation has been implicated to have diagnostic utility in PIOL. In this study, we screened consecutive vitreous biopsies for the presence of MYD88 L265P mutation to understand its diagnostic utility compared to conventional cytological analysis.Methods:Cytological analysis and MYD88 L265P mutation by PCR-based sequencing and restriction fragment length polymorphism (RFLP) were carried out on consecutive vitreous and subretinal biopsies collected from 21 patients. The diagnostic utility of the cytology and MYD88 L265P mutation analysis were compared.Results:Out of the 21 patients, 15 had clinical suspicion of having PIOL. Out of these suspected cases of PIOL, nine were confirmed on follow-up, while six were diagnosed as other intraocular pathologies. Diagnostic utility of MYD88 L265P mutation analysis revealed a sensitivity of 88.9%, specificity of 91.6%, positive and negative predictive value of 88.9% and 91.7%, respectively. Diagnostic accuracy of 90.5% was achieved with the mutation analysis that shows the superiority of MYD88 in both ruling in and ruling out PIOL. The diagnostic utility of MYD88 L265P mutation was superior to conventional cytological analysis.Conclusion:The analysis of MYD88 L265P mutation is reliable and efficient in the diagnosis of PIOL.  相似文献   
56.
57.
58.
The response to lepromin and Kveim antigens was compared and studied in 15 leprosy patients who were tuberculin negative. Of the 11 lepromin positive tuberculoid patients, 4 were Kveim positive, 1 was equivocal, and the rest were negative. Of the four lepromin negative lepromatous patients, one gave a positive Kveim test while the other three were negative. It has been shown that false-positive Kveim reactions are found in a higher percentage of South Indian leprosy patients than in those of other backgrounds, such as Japanese and Malaysian Chinese patients. It is also suggested that no definite relationship exists between the reaction of leprosy patients to lepromin and Kveim antigens. We further suggest that the anergy exhibited by lepromatous patients to the antigen of M. leprae is specific, as evidenced by the positive Kveim response in one lepromatous patient.  相似文献   
59.
60.
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