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   3204篇
  免费   144篇
  国内免费   13篇
耳鼻咽喉   29篇
儿科学   44篇
妇产科学   7篇
基础医学   479篇
口腔科学   106篇
临床医学   231篇
内科学   782篇
皮肤病学   46篇
神经病学   246篇
特种医学   74篇
外科学   446篇
综合类   3篇
预防医学   108篇
眼科学   93篇
药学   173篇
中国医学   4篇
肿瘤学   490篇
  2023年   13篇
  2022年   28篇
  2021年   73篇
  2020年   27篇
  2019年   44篇
  2018年   74篇
  2017年   69篇
  2016年   64篇
  2015年   68篇
  2014年   86篇
  2013年   100篇
  2012年   187篇
  2011年   179篇
  2010年   100篇
  2009年   108篇
  2008年   157篇
  2007年   154篇
  2006年   162篇
  2005年   174篇
  2004年   158篇
  2003年   147篇
  2002年   160篇
  2001年   79篇
  2000年   82篇
  1999年   82篇
  1998年   43篇
  1997年   46篇
  1996年   42篇
  1995年   29篇
  1994年   34篇
  1993年   26篇
  1992年   61篇
  1991年   65篇
  1990年   41篇
  1989年   44篇
  1988年   50篇
  1987年   31篇
  1986年   24篇
  1985年   48篇
  1984年   17篇
  1983年   16篇
  1981年   17篇
  1979年   11篇
  1978年   11篇
  1977年   10篇
  1975年   11篇
  1974年   16篇
  1972年   15篇
  1971年   13篇
  1969年   10篇
排序方式: 共有3361条查询结果,搜索用时 15 毫秒
1.
2.
Neurotransmitter- or neuromodulator-like actions ofl-DOPA were investigated with intracellular recordings from submucous plexus neurons of the guinea-pig caecum.l-DOPA at 30 nM augmented the amplitude of fast EPSPs, but did not affect depolarizations elicited by puff application of acetylcholine (ACh). The augmenting effect ofl-DOPA on the fast EPSPs was counteracted byl-DOPA methyl ester. The fast EPSPs were depressed by 10 μMl-DOPA, but transiently augmented after rinsing the drug.l-DOPA methyl ester did not affect the inhibitory action ofl-DOPA on the fast EPSPs, but antagonized the potentiation following the inhibition. The depolarization elicited by exogenously applied. ACh was inhibited by 10 μMl-DOPA. Intracellular Ca2+ concentrations ([Ca2+]i) of the neuronal soma were measured with fura-2 microfluorophotometry. The transient increase in the [Ca2+]i evoked by the somatic action potential (Δ[Ca2+]AP) was facilitated by 30 nMl-DOPA, but decreased by the drug at 10 μM. It is concluded thatl-DOPA at low concentrations enhances the Δ[Ca2+]AP, increasing the neurotransmitter release, but at high dose diminishes the Δ[Ca2+]AP, inhibiting the neurotransmission.  相似文献   
3.
4.
Ganciclovir resistance in cytomegalovirus (CMV) is an increasing problem in lung-transplant recipients with adverse clinical outcomes. We experienced the successful treatment of ganciclovir-resistant CMV infection in a lung-transplant recipient still receiving CMV prophylaxis. A 24-year-old woman with lymphangioleiomyomatosis underwent a living-donor lobar lung transplantation. She was a primary CMV mismatch (D+/R-) patient. She recovered from her postoperative complications, and was about to be discharged. However, she suffered ganciclovir-resistant CMV infection during prophylactic therapy. She was successfully treated with foscarnet, and is now alive without recurrence 18 months after surgery.  相似文献   
5.
Late-onset chylothorax occurred 49 days after right lower lobectomy for lung cancer in a 76-year-old man. Chylothorax was successfully managed by conservative treatment with chest tube drainage and an enteral low-fat diet. Chylothorax may occur in the late period after pulmonary resection and systematic mediastinal lymph node dissection for lung cancer, for which conservative management is the treatment of choice.  相似文献   
6.
7.
8.
We report a 73-year-old woman with typical clinical, histological and immunofluorescence features of pemphigoid nodularis. Direct immunofluorescence studies of prurigo nodularis-like lesions and peribullous skin showed the linear deposition of IgG and C3 at the basement membrane zone. Circulating IgG against the basement membrane was also detected by indirect immunofluorescence. The serum from the patient was shown to contain the autoantibody against 230 kDa hemidesmosomal antigen associated with bullous pemphigoid antigen.  相似文献   
9.
We report herein the case of a 77-year-old man with a left ventricular tumor originating from the papillary muscle of the left ventricular wall, in whom a successful tumor resection with mitral valve replacement was performed. The pathological diagnosis of the tumor was confirmed as cardiac fibroma. His postoperative course was uneventful and he is currently well with no signs of recurrence 2 years after surgery.  相似文献   
10.
The localization of pituitary adenylate cyclase-activating polypeptide (PACAP) in the hypothalamus-pituitary system in rats was examined in light and electron microscopic immunocytochemistry using a specific antiserum to synthetic PACAP 1–38 (R0831). In light microscopic study, intensely PACAP-immunostained perikarya were observed in the supraoptic and paraventricular magnocellular nucleus in the hypothalamus. In the median eminence, many immunoreactive nerve fibers were observed in the internal layer, but a few immunoreactive terminals were noticed in the external layer. In the pituitary gland, numerous immunoreactive nerve fibers were observed in the posterior lobe. In the intermediate lobe, moderately immunostained cells were observed, but in the anterior lobe no immunostained cells were noticed. In electron microscopic study, PACAP-immunoreactivity was examined by avidin-biotin peroxidase complex method. In the perikarya of the supraoptic and paraventricular magnocellular nucleus, DAB-reaction products were distributed diffusely in the cytoplasmic matrix, frequently attaching to the rough-surfaced endoplasmic reticulum. In the nerve terminals of the posterior lobe, reaction products were observed among the secretory granules, but sometimes upon them. In the cells of the intermediate lobe, reaction products were also distributed in the cytoplasmic matrix.  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