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   267683篇
  免费   16094篇
  国内免费   1045篇
耳鼻咽喉   3090篇
儿科学   8727篇
妇产科学   5887篇
基础医学   37323篇
口腔科学   10316篇
临床医学   21444篇
内科学   60420篇
皮肤病学   6811篇
神经病学   24187篇
特种医学   7678篇
外国民族医学   27篇
外科学   29953篇
综合类   1785篇
现状与发展   1篇
一般理论   109篇
预防医学   26730篇
眼科学   4828篇
药学   17230篇
中国医学   980篇
肿瘤学   17296篇
  2023年   1799篇
  2022年   3893篇
  2021年   6873篇
  2020年   4446篇
  2019年   6167篇
  2018年   7961篇
  2017年   6036篇
  2016年   6186篇
  2015年   7001篇
  2014年   9320篇
  2013年   12077篇
  2012年   18605篇
  2011年   19253篇
  2010年   10145篇
  2009年   9005篇
  2008年   15239篇
  2007年   15892篇
  2006年   14712篇
  2005年   14699篇
  2004年   13564篇
  2003年   12384篇
  2002年   9960篇
  2001年   5543篇
  2000年   5368篇
  1999年   5000篇
  1998年   2317篇
  1997年   1920篇
  1996年   1806篇
  1995年   1527篇
  1994年   1494篇
  1993年   1307篇
  1992年   2949篇
  1991年   2788篇
  1990年   2551篇
  1989年   2535篇
  1988年   2305篇
  1987年   2119篇
  1986年   1997篇
  1985年   1877篇
  1984年   1404篇
  1983年   1151篇
  1982年   731篇
  1981年   628篇
  1980年   613篇
  1979年   1005篇
  1978年   691篇
  1977年   552篇
  1975年   602篇
  1974年   620篇
  1973年   611篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
102.
Mammalian spermatogenesis is a well-organized process of cell development and differentiation. Meiosis expressed gene 1 (MEIG1) plays an essential role in the regulation of spermiogenesis. To explore potential mechanisms of MEIG1''s action, a yeast two-hybrid screen was conducted, and several potential binding partners were identified; one of them was membrane occupation and recognition nexus repeat containing 3 (MORN3). MORN3 mRNA is only abundant in mouse testis. In the testis, Morn3 mRNA is highly expressed in the spermiogenesis stage. Specific anti-MORN3 polyclonal antibody was generated against N-terminus of the full-length MORN3 protein, and MORN3 expression and localization was examined in vitro and in vivo. In transfected Chinese hamster ovary cells, the antibody specifically crossed-reacted the full-length MORN3 protein, and immunofluorescence staining revealed that MORN3 was localized throughout the cytoplasm. Among multiple mouse tissues, about 25 kDa protein, was identified only in the testis. The protein was highly expressed after day 20 of birth. Immunofluorescence staining on mixed testicular cells isolated from adult wild-type mice demonstrated that MORN3 was expressed in the acrosome in germ cells throughout spermiogenesis. The protein was also present in the manchette of elongating spermatids. The total MORN3 expression and acrosome localization were not changed in the Meig 1-deficient mice. However, its expression in manchette was dramatically reduced in the mutant mice. Our studies suggest that MORN3 is another regulator for spermatogenesis, probably together with MEIG1.  相似文献   
103.
The regrowth of amputated digit tips represents a unique regenerative healing in mammals with subcutaneous volume regrowth, restoration of dactylogram, and suppression of scar formation. Although factor analysis in amphibians and even in mice is easy to obtain, safety of harvesting biomaterial from human digit tip amputations for analysis has not yet been described.The aim of this study was to evaluate if recovering wound exudate does hamper clinical outcome or influence microbiologic or inflammation status.A predefined cohort of 18 patients with fresh digit tip amputations was randomly assigned to receive standard therapy (debridement, occlusive dressing) with (n = 9) or without (n = 9) collection of the whole wound exudate in every dressing change. Primary endpoint (lengthening) and secondary endpoints (regeneration of dactylogram, nail bed and bone healing, time to complete wound closure, scar formation, 2-point discrimination, microbiologic analysis, inflammatory factors interleukin (IL)-1α, tumor necrosis factor-α, IL-4, and IL-6) were determined by an independent, blinded observer.Patients’ characteristics showed no significant differences between the groups. All patients completed the study to the end of 3 months follow-up. Exudate collection did not influence primary and secondary endpoints. Furthermore, positive microbiologic findings as well as pus- and necrosis-like appearance neither impaired tissue restoration nor influenced inflammatory factor release.Here, the authors developed an easy and safe protocol for harvesting wound exudate from human digit tip amputations. For the first time, it was shown that harvesting does not impair regenerative healing. Using this method, further studies can be conducted to analyze regeneration associated factors in the human digit tip.DRKS.de Identifier: DRKS00006882 (UTN: U1111-1166-5723).  相似文献   
104.
105.
106.
Infantile hemangiomas (IHs) are the most common benign tumor of infancy, characterized by a natural history of early proliferation in the first months of life to eventual involution during childhood, often with residual fibrofatty tissue. Once involution has been achieved, IHs do not typically recur. We present two cases of exogenous growth hormone therapy resulting in the recurrence of IHs in late childhood, supported by radiological, immunohistochemical, in vitro, and in vivo evidence.  相似文献   
107.
108.
109.
110.
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