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   512362篇
  免费   33978篇
  国内免费   608篇
耳鼻咽喉   6892篇
儿科学   16829篇
妇产科学   13526篇
基础医学   84940篇
口腔科学   14457篇
临床医学   44178篇
内科学   93124篇
皮肤病学   12146篇
神经病学   36262篇
特种医学   18460篇
外国民族医学   63篇
外科学   76963篇
综合类   8456篇
一般理论   118篇
预防医学   38847篇
眼科学   12115篇
药学   40504篇
中国医学   1006篇
肿瘤学   28062篇
  2018年   4932篇
  2015年   4515篇
  2014年   6067篇
  2013年   9552篇
  2012年   12884篇
  2011年   14282篇
  2010年   8305篇
  2009年   7780篇
  2008年   13711篇
  2007年   14707篇
  2006年   14953篇
  2005年   14370篇
  2004年   14060篇
  2003年   13397篇
  2002年   13276篇
  2001年   24075篇
  2000年   25088篇
  1999年   20567篇
  1998年   5430篇
  1997年   4709篇
  1996年   5041篇
  1995年   4626篇
  1994年   4320篇
  1993年   4137篇
  1992年   15713篇
  1991年   16308篇
  1990年   16421篇
  1989年   15789篇
  1988年   14572篇
  1987年   14416篇
  1986年   13590篇
  1985年   12975篇
  1984年   9614篇
  1983年   8238篇
  1982年   4543篇
  1981年   4215篇
  1979年   9405篇
  1978年   6838篇
  1977年   5754篇
  1976年   5589篇
  1975年   6379篇
  1974年   7630篇
  1973年   7124篇
  1972年   6953篇
  1971年   6680篇
  1970年   6166篇
  1969年   5886篇
  1968年   5557篇
  1967年   5009篇
  1966年   4450篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
961.
962.
963.
964.
965.
966.
Prognostic significance of serum cholesterol in nursing home men   总被引:2,自引:0,他引:2  
Serum cholesterol was measured in 129 men (average age 70.6; range 41-96) of a Veterans Administration Nursing Home, and was correlated with other items in an extensive clinical data base. Serum cholesterol was less than 150 mg/dl in 13% of the subjects, and was less than 160 mg/dl in 18%. Cholesterol greater than 280 mg/dl occurred in 8%. Serum cholesterol varied directly (p less than 0.02) with: body weight, serum albumin, serum total protein, serum sodium, ability to walk, and ability to feed oneself; and indirectly (p less than 0.02) with death rate, degree of functional dependence, and serum SGOT and LDH. Nursing home men with cholesterol less than 150 mg/dl had a death rate of 63% during the 14 months after the cholesterol analysis, compared to a death rate of 9% in men with cholesterol greater than 150 mg/dl (p less than 0.05). Death rate during the year after the analysis was 52% if cholesterol was below 160 mg/dl, compared to 7% if it was above this threshold (p less than 0.05).  相似文献   
967.
The Preferred Provider Organization concept is quickly becoming more popular because of its relative cost-effectiveness and recent successes. Managed care through means of this mental health and substance abuse PPO may well serve as the prototype for the general health care cost containment efforts of the future for the self-insured insurance plans for Alabama state employees and teachers. The first year also revealed several problems in the original proposal especially with respect to the unintended attractiveness of inpatient/residential care. Consequently, copayment plans were added to dissuade unnecessary lengthy stays (see Table 2). Second, a new quality assurance mechanism has been added to further evaluate the need for admissions to facilities, as well as for the need for continued inpatient treatment. The Alabama Quality Assurance Foundation (AQAF) began on January 1, 1988, conducting the preadmission certification on all admissions based upon criteria established jointly by AQAF and the PPO providers. In addition, AQAF will conduct continuing stay reviews at predetermined time periods to ensure that continued treatment in an inpatient setting is indeed necessary.  相似文献   
968.
A mu-capture enzyme-linked immunosorbent assay (ELISA) for detecting chlamydia-specific IgM was developed by use of the heat stable, lipopolysaccharide group-specific antigen and an alkaline phosphatase-labelled anti-chlamydia group-specific monoclonal antibody conjugate. The test was used to study the serological response in chlamydial respiratory tract infection among patients with acute respiratory tract symptoms in Cambridgeshire during the past 7 years. Results were compared with those of the complement fixation test (CFT) in routine use as well as those of a whole inclusion indirect immunofluorescence (WIF) test for IgM. Correlation between results of the mu-capture ELISA and those of the WIF test was 87.5%. The percentage of patients in whom specific IgM was found fell with increasing age. This may be due to lack of recall of IgM as a response to reinfection. Chlamydia-specific IgM was more likely to be detected when the CFT titre was greater than or equal to 64 and was rarely detected more than 6 months after the onset of symptoms. However, several patients less than 20 years of age were found to have specific IgM with CF antibody titres less than 64. We have found the mu-capture ELISA a useful test for the diagnosis of respiratory tract chlamydial infections, particularly in younger patients.  相似文献   
969.
970.
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