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   31711篇
  免费   2566篇
  国内免费   83篇
耳鼻咽喉   538篇
儿科学   1266篇
妇产科学   1012篇
基础医学   4322篇
口腔科学   836篇
临床医学   2760篇
内科学   7362篇
皮肤病学   747篇
神经病学   3251篇
特种医学   1150篇
外国民族医学   3篇
外科学   3904篇
综合类   539篇
一般理论   43篇
预防医学   2304篇
眼科学   635篇
药学   1771篇
中国医学   8篇
肿瘤学   1909篇
  2021年   413篇
  2020年   269篇
  2019年   452篇
  2018年   507篇
  2017年   361篇
  2016年   406篇
  2015年   460篇
  2014年   643篇
  2013年   974篇
  2012年   1267篇
  2011年   1335篇
  2010年   795篇
  2009年   687篇
  2008年   1210篇
  2007年   1310篇
  2006年   1302篇
  2005年   1229篇
  2004年   1239篇
  2003年   1124篇
  2002年   1193篇
  2001年   1102篇
  2000年   1166篇
  1999年   982篇
  1998年   380篇
  1997年   323篇
  1996年   337篇
  1995年   311篇
  1994年   305篇
  1993年   318篇
  1992年   862篇
  1991年   805篇
  1990年   686篇
  1989年   738篇
  1988年   689篇
  1987年   720篇
  1986年   667篇
  1985年   698篇
  1984年   544篇
  1983年   477篇
  1982年   310篇
  1980年   261篇
  1979年   456篇
  1978年   307篇
  1977年   261篇
  1976年   285篇
  1975年   268篇
  1974年   297篇
  1973年   294篇
  1972年   267篇
  1971年   260篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
72.
In the last century, both the health and life expectancy of Americans improved dramatically. These gains were primarily the result of advances in public health. But the approaches used may not be adequate to achieve the next level of improvements in health. Because health exists in the context of social, environmental, community, religious, political, and other spheres, ecological approaches that incorporate behavioral and social science theory and methodologies may provide the best avenue for advancing health in the 21st century. In 1999, the New York City Department of Health (NYCDOH) undertook the task of integrating behavioral and social science into its public health practice. The experience serves as a case study on the integration process at a public health agency.  相似文献   
73.
Although some areas of adult ADHD knowledge remain unclear, there isa strong sense of how to proceed with diagnosis using current DSM-IV criteria as a guide. Thorough clinical interview, aided by the use of rating scales for current symptoms and collateral information about childhood from parents or siblings, forms the backbone of the assessment. The poor psychosocial outcomes of patients with ADHD. often a consequence of unrecognized,untreated disorder manifestation, also can serve as a diagnostic indicator. Diagnostic and symptom assessment scales also can be a significant helpin diagnosing and establishing the symptoms of ADHD in adults. It is important to remember that according to DSM-IV, the cardinal criteria for making the diagnosis are the presence of sufficient current symptoms and impairment in two realms (home, school/work, and social interactions). Accordingly, adult ADHD remains a clinical diagnosis, and the clinician-administered interview remains the cornerstone of diagnostic evaluation.  相似文献   
74.
Steroid 11 beta-hydroxylase deficiency is relatively frequent in Israel among North African Jews. Over a 39-year period, 38 affected individuals from 25 families were diagnosed. Nineteen families came from Morocco, and in another 2, one parent came from Morocco (80% of all parents). Demographic studies showed that most of their grandparents were born in the region of the Atlas Mountains. In Israel, the overall incidence of the disorder is estimated between 1 in 30,000 to 1 in 40,000 births, but in offspring of Moroccan Jews the ratio is 1 in 5,000 to 1 in 7,000, with an allele frequency of 1 in 70 to 1 in 84 and a carrier frequency of 1 in 35 to 1 in 42. The clinical expression is characterized by a wide range of variability in the signs of androgen and mineralocorticoid excess. Virilization in the female ranged from enlarged clitoris in the mildest forms, to markedly hypertrophied clitoris with penile urethra and fused labial-scrotal folds in the most severe forms. Hypertension causing vascular accidents and death was observed in both severe and mildly virilized patients, whereas masculinized females were sometimes normotensive. Based on historical evidence, the origin of the ancestors, and the onomastic analysis of the families surnames, we propose that the mutation of 11 beta-hydroxylase deficiency in Jews from Morocco may have originated in either the ancient Jewish settlers or the native Berber tribes who lived in the region of the Atlas Mountains in the southern region of Morocco before the destruction of the Second Temple by the Romans, in the year 70 C.E.  相似文献   
75.
Histologic and immunohistochemical properties of 53 medulloblastomas were analyzed with regard to clinical features and survival rate. No correlation was found between survival rate and histologic features of the tumor, such as desmoplastic reaction, number of mitoses, hemorrhages, necrosis, endothelial proliferation, glomerular arrangement, calcifications, rosettes, or oligodendroglial cells. However 82% of the patients with positive glial fibrillary acidic protein (GFAP) staining in numerous tumor cells survived more than 5 years; only 30% survived that long if their tumor cells were GFAP negative (P = 0.0093). This significant difference was not related to the mode of therapeutic protocol used. The authors suggest that GFAP staining may be a useful prognostic tool in medulloblastoma.  相似文献   
76.
When medical students become involved in patient care, concerns are raised that have ethical and possibly legal implications. In order to determine compliance with the guidelines of the U.S. government and the Joint Committee on Accreditation of Hospitals pertaining to informed consent, the authors conducted a study of hospital administrators, medical school department chairpersons, and medical school deans (with response rates ranging from 82.3 to 95.1 percent) concerning policies on student involvement in patient care. The results show that only 37.5 percent of all responding teaching hospitals specifically informed patients that students would be involved in care. Only 51 percent of the responding medical schools that specifically gave their students instruction or guidance on initial patient interaction as a matter of policy insisted that their students introduce themselves as students and clarify their role in patient care. The authors conclude that medical educators' compliance with the ethical requirements of informed consent is incomplete.  相似文献   
77.
78.
The cognitive status of 12 clinically stable children with congenital HIV infection, nine of whom were neurologically impaired, age three to nine years, was assessed using the Kaufman ABC test. Seven of the children had ARC; five were diagnosed as having AIDS. The same children were evaluated by standard neurologic examinations with Characterization of tone and fine motor functioning. Two were diagnosed as being mildly retarded; six were borderline; and four tested as being of average intelligence. Visual-spatial perceptual based functioning was found to be more impaired than were abstract reasoning and verbally mediated skills in six (50%) of the patients. This pattern of impaired information processing was found irrespective of overall cognitive status. On neurological and physiatric examination abnormal developmental histories were obtained, or poor fine motor coordination, abnormal tone and gait, and impaired rapidly alternating movements were found in 9 of the 12 subjects. These findings suggest selective impairment in distinct areas of neurologic and neuropsychological functioning during stable phases of HIV infection in a select group of children. These patterns appear to persist over time. They differ from the clustering of impaired skills seen in children of comparable socio-cultural backgrounds without HIV infection. Similarities in functioning are noted between this subgroup of children with AIDS and ARC and comparable groups with cerebral palsy.  相似文献   
79.
Identifying alcoholism in medical patients   总被引:1,自引:0,他引:1  
  相似文献   
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