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   34883篇
  免费   2183篇
  国内免费   290篇
耳鼻咽喉   454篇
儿科学   656篇
妇产科学   517篇
基础医学   4157篇
口腔科学   1626篇
临床医学   2991篇
内科学   9363篇
皮肤病学   430篇
神经病学   3409篇
特种医学   1600篇
外科学   5405篇
综合类   111篇
一般理论   6篇
预防医学   1679篇
眼科学   557篇
药学   1757篇
中国医学   72篇
肿瘤学   2566篇
  2024年   33篇
  2023年   408篇
  2022年   682篇
  2021年   1267篇
  2020年   785篇
  2019年   1040篇
  2018年   1257篇
  2017年   989篇
  2016年   1111篇
  2015年   1184篇
  2014年   1553篇
  2013年   1895篇
  2012年   2808篇
  2011年   2720篇
  2010年   1562篇
  2009年   1443篇
  2008年   2192篇
  2007年   2329篇
  2006年   2079篇
  2005年   1878篇
  2004年   1680篇
  2003年   1510篇
  2002年   1310篇
  2001年   286篇
  2000年   256篇
  1999年   269篇
  1998年   305篇
  1997年   290篇
  1996年   232篇
  1995年   197篇
  1994年   188篇
  1993年   158篇
  1992年   133篇
  1991年   105篇
  1990年   111篇
  1989年   96篇
  1988年   116篇
  1987年   95篇
  1986年   77篇
  1985年   95篇
  1984年   65篇
  1983年   56篇
  1982年   70篇
  1981年   59篇
  1980年   41篇
  1979年   48篇
  1978年   35篇
  1977年   36篇
  1976年   28篇
  1973年   31篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
In the present study we evaluated the effects of climacteric modifications on body weight and fat distribution. From women attending a menopause clinic we selected 2175 untreated, normal healthy women who were divided into three groups: premenopausal (n = 540), perimenopausal (n = 750) and postmenopausal (n = 885), and compared them with 354 postmenopausal women receiving different forms of hormone replacement therapy (HRT). The total body fat tissue mass and distribution were analyzed using dual-energy X-ray absorptiometry. Body weight and body mass index (BMI) were significantly higher in perimenopausal and postmenopausal than in premenopausal women. Mean total body fat and fat as a percentage of soft tissue were significantly (p < 0.05) higher in the perimenopausal and postmenopausal groups than in the premenopausal group. Fat tissue and regional fat tissue as a percentage of total fat tissue were higher in the trunk (p < 0.0001) and arms (p < 0.0001) in perimenopausal and postmenopausal than in premenopausal women. In postmenopausal women, leg fat tissue was significantly (p < 0.05) lower than in premenopausal and perimenopausal groups. Total body and leg lean tissue were significantly lower (p < 0.05) in postmenopausal than in premenopausal and perimenopausal women. In age-matched women with similar BMI, total body fat as a percentage of soft tissue was significantly (p < 0.001) higher in the perimenopausal and postmenopausal groups than in the premenopausal group. As for body fat distribution, fat as a percentage of total fat tissue was significantly higher in the trunk (p < 0.0001) region in perimenopausal and postmenopausal women compared with the premenopausal group. In the legs, fat as a percentage of total fat tissue was significantly higher (p < 0.05) in the premenopausal than in the postmenopausal group. In the arms a slight but not significant (p < 0.18) difference was shown in fat distribution between the three untreated groups. In age-matched HRT-treated postmenopausal women, the fat tissue was similar to that in the premenopausal group. The present results confirm that endocrine changes during the menopausal transition, rather than the aging process, are related to changes in body weight and fat distribution. Perimenopausal and postmenopausal women show a shift to a central, android fat distribution that can be counteracted by HRT.  相似文献   
32.
33.
Lateral unicompartmental knee arthroplasty (UKA) is a valid alternative treatment in the event of arthritis confined to the lateral compartment. This paper examines its indications, technique and short to medium-term results. A total of 159 Miller–Galante cemented UKA prostheses (Zimmer, Warsaw, Indiana) were implanted consecutively (131 medial and 28 lateral) by the same surgeon. This study investigates 28 lateral UKAs in 27 patients. Twenty-five implants in 24 patients (including a subject operated bilaterally) were followed up for 12–60 months. Three patients were discarded on account of to short a follow-up period. The Hospital for Special Surgery (HSS) knee score was used to compare the pre- and post-operative results of the lateral UKA patients. The HSS score improved from a pre-op mean of 59.92 (range 48–68) to 88.04 (range 71–95) at the last follow-up. There was a positive increase in the pain, function and ROM components of the score. The lateral UKA prosthesis can be regarded as a sound alternative to total knee replacement. Correct patient selection on the basis of optimum surgical indications, however, is essential. No benefits of funds were received in support of the study.  相似文献   
34.
Recurrent focal glomerulosclerosis (FSGS) in renal allografts has remained a frustrating and enigmatic disease. Recent studies on gene mutations encoding podocin and other components of the slit-diaphragm in patients with native kidney nephrotic syndrome have underscored the heterogenecity of the idiopathic form of FSGS. While familial FSGS rarely recurs following transplantation, the sporadic variety of FSGS is associated with a 30% recurrence rate. The patients with the sporadic variety of FSGS who have homozygous or complex heterozygous podocin mutations have a low recurrence rate. In the other patients with sporadic FSGS, a more complex and likely multifactorial etiology accounts for the recurrence of FSGS. The role of CD80 expression on podocytes is intriguing but requires confirmation in kidney biopsies of patients with recurrent FSGS. Recent findings on podocin genomics, the permeability factor and CD80 expression may ultimately lead to a better understanding of recurrent FSGS as well as a more effective approach to its prevention and treatment.  相似文献   
35.
36.
37.
38.
39.
To analyse the effect of concomitant cognitive or motor task performance on balance control in Parkinson's disease (PD), we performed a posturographic study in 24 PD patients and in 20 sex- and age-matched control subjects. Postural sway was measured with eyes open (EO) and eyes closed (EC) during quiet stance and during performance of calculation or motor sequence of thumb opposition to the other fingers. No difference of centre of foot pressure (COP) parameters was observed during quiet standing (either EO or EC) between patients and controls, but visual deprivation induced in both groups a worsening of postural stability. COP area was significantly increased in PD patients during dual task performance, whereas no difference of COP path and x-y axes was observed. The effects induced by the performance of cognitive or motor task were significantly more evident in PD patients with clinical evidence of postural instability (presence of prior falls in the history). This study demonstrates that dual task interference on postural control can be observed in PD patients during performance of cognitive as well as motor tasks. The balance deterioration during dual task performance was significantly enhanced in patients with history of prior falls. These findings have some implications for the strategies to be used in reducing the risk of fall in PD.  相似文献   
40.
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