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   4529篇
  免费   197篇
  国内免费   31篇
耳鼻咽喉   51篇
儿科学   98篇
妇产科学   31篇
基础医学   686篇
口腔科学   118篇
临床医学   237篇
内科学   1154篇
皮肤病学   167篇
神经病学   395篇
特种医学   210篇
外科学   806篇
综合类   29篇
预防医学   55篇
眼科学   19篇
药学   263篇
中国医学   13篇
肿瘤学   425篇
  2023年   25篇
  2022年   48篇
  2021年   68篇
  2020年   55篇
  2019年   64篇
  2018年   89篇
  2017年   56篇
  2016年   89篇
  2015年   71篇
  2014年   108篇
  2013年   121篇
  2012年   227篇
  2011年   244篇
  2010年   152篇
  2009年   128篇
  2008年   245篇
  2007年   260篇
  2006年   232篇
  2005年   257篇
  2004年   268篇
  2003年   257篇
  2002年   305篇
  2001年   104篇
  2000年   129篇
  1999年   100篇
  1998年   58篇
  1997年   58篇
  1996年   35篇
  1995年   51篇
  1994年   41篇
  1993年   43篇
  1992年   73篇
  1991年   65篇
  1990年   72篇
  1989年   60篇
  1988年   51篇
  1987年   53篇
  1986年   46篇
  1985年   32篇
  1984年   37篇
  1983年   26篇
  1981年   21篇
  1980年   18篇
  1979年   19篇
  1977年   17篇
  1973年   16篇
  1972年   20篇
  1970年   17篇
  1967年   16篇
  1966年   15篇
排序方式: 共有4757条查询结果,搜索用时 0 毫秒
91.
92.
93.
94.
95.
96.
97.
Gonadotropin-inhibitory hormone (GnIH) is a hypothalamic dodecapeptide (SIKPSAYLPLRF-NH(2)) that directly inhibits gonadotropin synthesis and release from quail pituitary. The action of GnIH is mediated by a novel G-protein coupled receptor. This gonadotropin-inhibitory system may be widespread in vertebrates, at least birds and mammals. In these higher vertebrates, histological evidence suggests contact of GnIH immunoreactive axon terminals with GnRH neurons, thus indicating direct regulation of GnRH neuronal activity by GnIH. In this study we investigated the interaction of GnIH and GnRH-I and -II neurons in European starling (Sturnus vulgaris) brain. Cloned starling GnIH precursor cDNA encoded three peptides that possess characteristic LPXRF-amide (X = L or Q) motifs at the C termini. Starling GnIH was further identified as SIKPFANLPLRF-NH(2) by mass spectrometry combined with immunoaffinity purification. GnIH neurons, identified by in situ hybridization and immunocytochemistry (ICC), were clustered in the hypothalamic paraventricular nucleus. GnIH immunoreactive fiber terminals were present in the external layer of the median eminence in addition to the preoptic area and midbrain, where GnRH-I and GnRH-II neuronal cell bodies exist, respectively. GnIH axon terminals on GnRH-I and -II neurons were shown by GnIH and GnRH double-label ICC. Furthermore, the expression of starling GnIH receptor mRNA was identified in both GnRH-I and GnRH-II neurons by in situ hybridization combined with GnRH ICC. The cellular localization of GnIH receptor has not previously been identified in any vertebrate brain. Thus, GnIH may regulate reproduction of vertebrates by directly modulating GnRH-I and GnRH-II neuronal activity, in addition to influencing the pituitary gland.  相似文献   
98.
A 54-year old man was admitted with general fatigue, muscle weakness and dyspnea on effort. Medical examinations led to a diagnosis of small cell lung carcinoma (SCLC) with Lambert-Eaton myasthenic syndrome (LEMS). Marked improvement of SCLC and symptoms of LEMS were recognized twice during chemoradiotherapy. On his third admission, he showed muscle weakness, dysaethesia, and neurodysfunction of the bladder and rectum. We initially considered these symptoms to be due to spinal metastasis because MRI findings showed multiple spinal metastases. However, electoromyogram and nerve conduction study demonstrated that his muscle weakness resulted from LEMS though dysethesia and neurodysfunction of bladder and rectum were caused by spinal metastasis. We believe that it is important to perform electomyogram and nerve conduction studies, not only radiographic findings, to detect the "hidden" symptoms of LEMS.  相似文献   
99.
A 69-year-old woman underwent percutaneous coronary intervention for a severe stenotic lesion in the bifurcation of the mid-left anterior descending artery and first diagonal branch. A single stent was implanted into the left anterior descending artery. After the stent strut was dilated by balloon inflation in the diagonal branch, dissection occurred at the ostium of the diagonal branch and resulted in side branch occlusion due to hematoma. Bailout stenting was performed in the diagonal branch, but thrombus projection occurred in the left anterior descending artery. Aspiration, balloon inflation and thrombolytic therapy were performed, but distal embolism developed. This case illustrates that thrombus projection caused by stenting in a side branch may occur as a rare complication in percutaneous coronary intervention.  相似文献   
100.
A 54-year old man was admitted to our hospital because of high fever, productive cough and purpura in both legs in June 2005. Urinalysis showed microscopic hematuria and proteinuria. Chest radiograph showed consolidation of right upper field. Because acid-fast bacilli and polymerase chain reaction test for Mycobacterium tuberculosis were positive in bronchial lavage fluid, we made a diagnosis of pulmonary tuberculosis, and prescribed antituberculosis therapy with isoniazid, rifampicin, ethambutol and pyrazinamide. In addition, anaphylactoid purpura was diagnosed by skin biopsy. In July 2005, renal function was deteriorated and nephrosis appeared. We treated with corticosteroid in addition to antituberculosis therapy. His symptoms and renal dysfunction improved. We report a rare case of an anaphylactoid purpura following occurence of pulmonary tuberculosis.  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