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   14783篇
  免费   888篇
  国内免费   88篇
耳鼻咽喉   179篇
儿科学   258篇
妇产科学   293篇
基础医学   2157篇
口腔科学   1503篇
临床医学   1048篇
内科学   2990篇
皮肤病学   340篇
神经病学   1127篇
特种医学   531篇
外科学   1381篇
综合类   166篇
一般理论   5篇
预防医学   1634篇
眼科学   214篇
药学   1182篇
  1篇
中国医学   145篇
肿瘤学   605篇
  2023年   128篇
  2022年   279篇
  2021年   508篇
  2020年   357篇
  2019年   446篇
  2018年   556篇
  2017年   366篇
  2016年   413篇
  2015年   510篇
  2014年   720篇
  2013年   790篇
  2012年   1133篇
  2011年   1330篇
  2010年   653篇
  2009年   533篇
  2008年   905篇
  2007年   943篇
  2006年   688篇
  2005年   690篇
  2004年   558篇
  2003年   498篇
  2002年   407篇
  2001年   284篇
  2000年   266篇
  1999年   240篇
  1998年   120篇
  1997年   106篇
  1996年   86篇
  1995年   55篇
  1994年   50篇
  1993年   50篇
  1992年   102篇
  1991年   107篇
  1990年   94篇
  1989年   84篇
  1988年   75篇
  1987年   62篇
  1986年   66篇
  1985年   69篇
  1984年   41篇
  1983年   37篇
  1982年   42篇
  1981年   27篇
  1980年   29篇
  1979年   29篇
  1978年   17篇
  1977年   21篇
  1975年   20篇
  1973年   20篇
  1966年   16篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
Melatonin, the main hormone produced by the pineal gland, is secreted in a circadian manner (24‐hr period), and its oscillation influences several circadian biological rhythms, such as the regulation of clock genes expression (chronobiotic effect) and the modulation of several endocrine functions in peripheral tissues. Assuming that the circadian synchronization of clock genes can play a role in the regulation of energy metabolism and it is influenced by melatonin, our study was designed to assess possible alterations as a consequence of melatonin absence on the circadian expression of clock genes in the epididymal adipose tissue of male Wistar rats and the possible metabolic repercussions to this tissue. Our data show that pinealectomy indeed has impacts on molecular events: it abolishes the daily pattern of the expression of Clock, Per2, and Cry1 clock genes and Pparγ expression, significantly increases the amplitude of daily expression of Rev‐erbα, and affects the pattern of and impairs adipokine production, leading to a decrease in leptin levels. However, regarding some metabolic aspects of adipocyte functions, such as its ability to synthesize triacylglycerols from glucose along 24 hr, was not compromised by pinealectomy, although the daily profile of the lipogenic enzymes expression (ATP‐citrate lyase, malic enzyme, fatty acid synthase, and glucose‐6‐phosphate dehydrogenase) was abolished in pinealectomized animals.  相似文献   
5.
Granulomatous slack skin is an indolent T-cell lymphoma, considered to be a variant of mycosis fungoides. Clinically it is characterized by areas of redundant skin, wrinkled, inelastic, with variable erythema and infiltration besides a poikilodermic surface. A differential diagnosis unknown to most dermatologists is the giant cell tumor of soft tissue, which is an extremely rare low-grade sarcoma. The authors report a patient who had undergone extensive surgery because of a primary diagnosis of giant cell tumor of soft tissue, but which proved to be granulomatous slack skin after a second interventional procedure with confirmatory histopathology.  相似文献   
6.
7.
Purpose:This study assessed the regeneration potential of mesenchymal stem cells (MSC) from adipose tissue associated with platelet-rich plasma (PRP) in bone regeneration.Methods:Thirty Wistar rats (Rattus norvegicus albinos) were divided into five groups (according to the grafting material and time to euthanasia): (1) autograft - 14 days (control), (2) autograft - 28 days (control), (3) MSC + PRP - 14 days, (4) MSC + PRP + papaverine - 14 days and (5) MSC + PRP + papaverine - 28 days. After euthanasia, the graft was removed and histological slides were prepared. They were assessed by a blinded pathologist using a previously published histological scale as parameter.Results:There was some degree of neoformed bone trabeculae (NBT) in 93.3% of the samples, as well as osteoblastic activity (OA). The autograft groups (14 and 28 days) had higher levels in the formation of bone trabeculae. Nonparametric data were analyzed using the Wilcoxon-Mann-Whitney test and proved not to be statistically significant at p < 0.05.Conclusions:Experimental parietal bone reconstruction, combining MSC, PRP and papaverine presented regeneration in all groups with no significant difference among them.Key words: Bone Regeneration, Platelet-Rich Plasma, Tissue Engineering, Rats  相似文献   
8.
9.
10.
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