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   351848篇
  免费   8956篇
  国内免费   601篇
耳鼻咽喉   4049篇
儿科学   11773篇
妇产科学   6929篇
基础医学   40093篇
口腔科学   8655篇
临床医学   23652篇
内科学   74399篇
皮肤病学   6254篇
神经病学   30710篇
特种医学   12852篇
外国民族医学   2篇
外科学   50825篇
综合类   3366篇
一般理论   53篇
预防医学   34569篇
眼科学   6572篇
药学   21515篇
中国医学   1571篇
肿瘤学   23566篇
  2023年   1153篇
  2022年   2157篇
  2021年   5116篇
  2020年   2603篇
  2019年   4698篇
  2018年   27709篇
  2017年   20641篇
  2016年   22708篇
  2015年   5177篇
  2014年   6707篇
  2013年   8987篇
  2012年   19679篇
  2011年   34253篇
  2010年   25690篇
  2009年   17098篇
  2008年   29723篇
  2007年   32432篇
  2006年   11091篇
  2005年   12592篇
  2004年   12620篇
  2003年   12888篇
  2002年   10374篇
  2001年   4790篇
  2000年   5450篇
  1999年   4210篇
  1998年   1260篇
  1997年   1026篇
  1996年   781篇
  1995年   731篇
  1994年   592篇
  1993年   453篇
  1992年   1610篇
  1991年   1397篇
  1990年   1289篇
  1989年   1026篇
  1988年   889篇
  1987年   808篇
  1986年   802篇
  1985年   712篇
  1984年   522篇
  1983年   455篇
  1979年   457篇
  1978年   331篇
  1974年   416篇
  1973年   404篇
  1972年   344篇
  1971年   367篇
  1970年   352篇
  1969年   373篇
  1968年   327篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
52.
Although previous studies have shown successful treatment of persistent diarrhea (PD) with the use of yogurt-based diets, some recent ones speculate the need of special formulas for the nutritional management of PD complicated cases. In the present study, we tested the hypothesis that the consumption of 3 lactose-free diets, with different degrees of complexity, is associated with lower stool output and shorter duration of diarrhea when compared with the use of a yogurt-based one on the nutritional management of PD. A total of 154 male infants, aged between 1 and 30 months, with PD and with or without dehydration, were randomly assigned to 1 of 4 treatment groups. Throughout the study, the patients were placed in a metabolic unit; their body weights and intakes of oral rehydration solution, water, and formula diets, in addition to outputs of stool, urine, and vomit, were measured and recorded at 24-hour intervals. Four different diets were used in this study: diet 1, yogurt-based formula; diet 2, soy-based formula; diet 3, hydrolyzed protein-based formula; and diet 4, amino acid–based formula. Throughout the study, only these formula diets were fed to the children. The data showed that children fed the yogurt-based diet (diet 1) or the amino acid–based diet (diet 4) had a significant reduction in stool output and in the duration of diarrhea. The use of an inexpensive and worldwide-available yogurt-based diet is recommended as the first choice for the nutritional management of mild to moderate PD. For the few complicated PD cases, when available, a more complex amino acid–based diet should be reserved for the nutritional management of these unresponsive and severe presentations. Soy-based or casein-based diets do not offer any specific advantage or benefits and do not seem to have a place in the management of PD.  相似文献   
53.
54.

Introduction  

This paper presents the results of a study on the psychometric properties of an authorized Spanish version of the McMaster Family Assessment Device, a self-report measure of family functioning.  相似文献   
55.
Glomeruloid haemangioma is considered a specific marker of POEMS ( p olyneuropathy, o rganomegaly, e ndocrinopathy, M -protein and s kin changes) syndrome and it is usually but not always associated with multicentric Castleman's disease. We report a 78-year-old man who presented with a single, red-violet soft nodule with superficial telangiectases on the scalp. Histopathologically, the lesion consisted of lobules of coiled aggregated capillaries that involved the lumina of dilated vascular structures, mimicking renal glomeruli. A collagenous stroma separated the capillary lobules, and eosinophilic, periodic-acid–Schiff positive globules of varying sizes and shapes were seen within the cytoplasm of endothelial cells. Immunohistochemical studies with antibodies against IgA and IgG, and against the kappa and lambda light chains of immunoglobulins showed immunoreactivity within the eosinophilic globules. Results of complete blood count, liver, renal and thyroid function tests, fasting blood sugar measurement, serum levels of oestradiol, testosterone, prolactin and cortisol, serum protein electrophoresis, immunoelectrophoresis and immunofixation yielded normal or negative results. No Bence–Jones proteinuria was found in a sample from a 24-h urine collection. To our knowledge, only two cases of glomeruloid haemangioma have been previously reported in patients without POEMS syndrome. We describe the third case of glomeruloid haemangioma in a patient without features of POEMS syndrome.  相似文献   
56.
57.
58.
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