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   24797篇
  免费   1532篇
  国内免费   163篇
耳鼻咽喉   295篇
儿科学   769篇
妇产科学   723篇
基础医学   2484篇
口腔科学   724篇
临床医学   2068篇
内科学   5443篇
皮肤病学   520篇
神经病学   1134篇
特种医学   823篇
外国民族医学   11篇
外科学   4458篇
综合类   713篇
现状与发展   1篇
一般理论   21篇
预防医学   1712篇
眼科学   722篇
药学   2163篇
中国医学   156篇
肿瘤学   1552篇
  2023年   349篇
  2022年   1031篇
  2021年   1442篇
  2020年   755篇
  2019年   962篇
  2018年   1276篇
  2017年   769篇
  2016年   800篇
  2015年   881篇
  2014年   1103篇
  2013年   1346篇
  2012年   1875篇
  2011年   1912篇
  2010年   983篇
  2009年   816篇
  2008年   1202篇
  2007年   1280篇
  2006年   1125篇
  2005年   970篇
  2004年   909篇
  2003年   765篇
  2002年   711篇
  2001年   345篇
  2000年   325篇
  1999年   307篇
  1998年   166篇
  1997年   117篇
  1996年   105篇
  1995年   109篇
  1994年   70篇
  1993年   55篇
  1992年   132篇
  1991年   121篇
  1990年   119篇
  1989年   106篇
  1988年   100篇
  1987年   94篇
  1986年   98篇
  1985年   87篇
  1984年   71篇
  1983年   87篇
  1982年   37篇
  1981年   46篇
  1980年   32篇
  1979年   79篇
  1978年   45篇
  1977年   54篇
  1976年   41篇
  1975年   46篇
  1974年   40篇
排序方式: 共有10000条查询结果,搜索用时 19 毫秒
71.
72.
73.
74.
75.
Journal of Public Health - Dyslipidemia is a major risk factor known to be associated with diabetes and cardiovascular diseases. This study determined the frequency of lipid abnormalities among...  相似文献   
76.
The electrorectogram in Hirschsprung's disease   总被引:1,自引:0,他引:1  
The electrorectographic pattern of Hirschsprung's disease (HD) was studied in 14 HD patients with a mean age of 4.6 ± 1.5 years; 7 healthy children acted as controls. Monpolar recordings were made from a silver-silver chloride electrode situated 1 cm from the tip of a 4 F catheter attached to the rectal mucosa by suction. At least four 120-min recording sessions were performed for each subject. No complications were encountered. Regular and reproducible triphasic pacesetter potentials (PP) were recorded from all healthy children, followed randomly by bursts of action potentials (AP). No PP or AP were recorded from patients with HD; the silent electrorectogram (ERG) was reproducible. Since numerous difficulties in histopathologic interpretation affect the reliability of rectal biopsy for the diagnosis of HD, the ERG may play a role in this respect. The ERG is noninvasive and nonradiologic; however, until this investigati tool is substantiated by the work of other investigators, a histologic diagnosis needs to be made before undertaking a pull-through procedure.  相似文献   
77.
Constricting band penile injuries in children may be caused by inadvertent entrapment by a variety of agents including hair, thread, and circumcision dressings. Alternatively, the offending band may have been self-applied or applied by an attendant. Unrelieved, the band causes serious vascular occlusion, progressive tissue necrosis, and injury to the urethra and erectile tissue. We report a case of CBPI in a 12-year-old circumcised boy. The glans was attached to the penile shaft by a tenuous segment of tissue dorsally with complete transection of the urethra. A three-stage reconstruction using a delayed groin flap was successful.  相似文献   
78.
Fifty four patients presenting by huge splenomegaly were admitted to Tropical Medicine Department, El-Minia University Hospital. Tissue biopsy revealed pure bilharziasis due to S. hematobium in 10 (19%) cases, liver cirrhosis in 23 (42%), mixed schistosomiasis and cirrhosis in 8 (15%), hepatoma in 3 (6%), lymphoma in 6 (11%) and hematological diseases in the form of chronic myeloid leukemia in 2 (3.5%) and thalassemia major in 2 (3.5%) cases. The sensitivity and specificity of abdominal ultrasonography was 100% and 97% in cases of schistosomiasis, 100% and 100% in cases of hepatoma, 87% and 100% in cases of liver cirrhosis, 33% and 100% in cases of lymphoma respectively. There was a positive significant correlation between endoscopic variceal grading, portal vein diameter, splenic vein diameter, size of the spleen and the grading of the portal tract thickenings. The pathological and ultrasonographic diagnosis was the same in 38 (70%) cases. Splenogram was characteristic but not diagnostic in cases of schistosomiasis and liver cirrhosis. It was diagnostic and similar to peripheral blood picture in the 2 cases of chronic myeloid leukemia and was normal in cases of thalassemia major. Splenic aspiration was able to diagnose all cases of lymphomas. It can be considered as a useful adjunct to the usual diagnostic procedures, both in staging and follow up, especially in cases presenting only by splenomegaly.  相似文献   
79.
80.
The purpose of this study is to develop and test the reliability and validity of an Egyptian version of the Children's Health Locus of Control scale. A cross sectional study design was applied using a stratified random sample of 930 students from the final two grades of primary and all grades of the preparatory schools. A further convenience sample of 120 students was selected to examine test-retest reliability of the scale. A preliminary instrument was developed and consisted of 40 statements having one of two response forms; a Yes/No format and a 4-point Likert scale format From data analysis the later format showed higher validity and reliability than the former one. Construct validity of the scale is evidenced by the factor analysis which revealed five factors (Internal, Chance, Powerful Others, Fate and Self blame) consistent with the previous theoretical model of HLC. As indicated by eta coefficient the scale and the subscales showed strong discriminating power between subjects. The known group comparison indicated a good criterion validity of the scale and the subscales. The scale showed a considerable reliability as alpha coefficient was 0.73 with test-retest reliability of 0.65. Comparison of different groups of students indicated that the scale could be used with confidence for all age groups, though it was more reliable for the preparatory phase, for private and governmental schools for males and females and for different social strata. Further testing of the developed scale is indicated among Egyptian children in different cultures.  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