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   4347篇
  免费   185篇
  国内免费   42篇
耳鼻咽喉   15篇
儿科学   71篇
妇产科学   23篇
基础医学   446篇
口腔科学   173篇
临床医学   260篇
内科学   1206篇
皮肤病学   55篇
神经病学   209篇
特种医学   111篇
外科学   849篇
综合类   11篇
预防医学   122篇
眼科学   59篇
药学   456篇
中国医学   26篇
肿瘤学   482篇
  2023年   18篇
  2022年   40篇
  2021年   100篇
  2020年   33篇
  2019年   47篇
  2018年   70篇
  2017年   57篇
  2016年   82篇
  2015年   95篇
  2014年   104篇
  2013年   129篇
  2012年   189篇
  2011年   214篇
  2010年   135篇
  2009年   74篇
  2008年   189篇
  2007年   223篇
  2006年   192篇
  2005年   208篇
  2004年   195篇
  2003年   159篇
  2002年   162篇
  2001年   149篇
  2000年   148篇
  1999年   138篇
  1998年   54篇
  1997年   42篇
  1996年   43篇
  1995年   44篇
  1994年   24篇
  1993年   30篇
  1992年   89篇
  1991年   108篇
  1990年   94篇
  1989年   95篇
  1988年   98篇
  1987年   85篇
  1986年   80篇
  1985年   89篇
  1984年   45篇
  1983年   50篇
  1982年   27篇
  1981年   25篇
  1980年   28篇
  1979年   39篇
  1978年   23篇
  1977年   20篇
  1973年   25篇
  1970年   21篇
  1969年   26篇
排序方式: 共有4574条查询结果,搜索用时 31 毫秒
81.
A 39-year-old man with dyspnea was revealed to have severe pneumothorax and received partial resection of the left upper lobe after unsuccessful drainage. Necrotizing epitheloid granuloma was found in the resected lung and Mycobacterium fortuitum was detected from the lesion. Chemotherapy with levofloxacin and clarithromycin was started one year after surgery because of the newly found nodular shadow near the lesion. The case experienced pyothorax due to pulmonary tuberculosis three years before and Mycobacterium avium pleuritis one year before this episode. Three-time mycobacterial pleural infection in three years seems to be uncommon. Furthermore this is the first report of pneumothorax associated with pulmonary Mycobacterium fortuitum infection.  相似文献   
82.
A 73-year-old woman was admitted with consciousness disturbance following a fever. Abdominal computed tomography revealed a large liver abscess with which the presence of Desulfovibrio desulfuricans and Escherichia coli was confirmed by thorough blood and abscess content culture. Empiric meropenem treatment was switched to cefoperazone/sulbactam, followed by ampicillin/sulbactam based on susceptibility testing. Desulfovibrio desulfuricans is a common bacterium that rarely causes liver abscess and may be overlooked during co-infection due to overgrowth of the accompanying bacteria. Clinicians should bear Desulfovibrio desulfuricans in mind and select the appropriate antibiotics according to susceptibility testing when anaerobic bacteria are detected in a liver abscess.  相似文献   
83.
84.
85.
Journal of Gastroenterology - Hepatitis B virus (HBV) is one of the most prevalent chronic viral infections that causes chronic hepatitis B (CHB). In Japan, genotypes B and C account for most of...  相似文献   
86.
87.
88.
Pharmacological characteristics of the voltage-dependent calcium channel (VDCC) of the pancreatic B-cell were studied using omega-conotoxin (omega CgTX) and dihydropyridine (DHP) calcium channel blockers. High glucose and potassium (K+) depolarization were employed as the stimulant of insulin release. omega CgTX (greater than 50 nM), a blocker of neural, but not muscular, Ca2+ channels, partially blocked (27%) the second, but not the first, phase of glucose-induced insulin release without a significant effect on K+ depolarization-induced insulin release. The DHP Ca2+ channel blocker nifedipine inhibited both phases of glucose-induced insulin release (ED50 = 200 nM) and completely abolished both phases of response at 10 microM. In contrast, the DHP Ca2+ channel blocker only partially suppressed (75% at 10 microM) K+ depolarization-induced insulin release with an ED50 of 100 nM. We conclude that pancreatic B-cell possesses at least two classes of VDCCs; one is DHP sensitive, and the other DHP insensitive. Partial suppression of the second phase of glucose-induced insulin release by a high concentration of omega CgTX may be due to its toxic effect on the secretory machinery other than VDCC.  相似文献   
89.
AIM: Nonalcoholic steatohepatitis (NASH) is a severe form of nonalcoholic fatty liver disease (NAFLD), and progresses to the end stage of liver disease. Biochemical markers of liver fibrosis are strongly associated with the degree of histological liver fibrosis in patients with chronic liver disease. However, data are few on the usefulness of markers in NAFLD patients. The aim of this study was to identify better noninvasive predictors of hepatic fibrosis, with special focus on markers of liver fibrosis, type VI collagen 7S domain and hyaluronic acid. METHODS: One hundred and twelve patients with histologically proven NAFLD were studied. RESULTS: The histological stage of NAFLD correlated with several clinical and biochemical variables, the extent of hepatic fibrosis and the markers of liver fibrosis were relatively strong associated. The best cutoff values to detect NASH were assessed by using receiver operating characteristic analysis: type VI collagen 75 domain ≥5.0 ng/mL, hyaluronic acid ≥43 ng/mL. Both markers had a high positive predictive value: type VI collagen 7S domain, 86% and hyaluronic acid, 92%. Diagnostic accuracies of these markers were evaluated to detect severe fibrosis. Both markers showed high negative predictive values: type VI collagen 7S domain (≥5.0 ng/mL), 84% and hyaluronic acid (≥50 ng/mL), 78%, and were significantly and independently associated with the presence of NASH or severe fibrosis by logistic regression analysis. CONCLUSION: Both markers of liver fibrosis are useful in discriminating NASH from fatty liver alone or patients with severe fibrosis from patients with non-severe fibrosis.  相似文献   
90.
Komatsu Y  Yasoda A  Chusho H  Nakao K 《Clinical calcium》2003,13(12):1578-1581
C-type natiruetic peptide (CNP) showed a potent effect on the elongation of the tibial organ culture system. CNP also corrected the dwarfing phenotype of the CNP knockout mice. These results suggest that CNP is the novel promoter of the endochondral ossification, and that CNP/GC-B activation is possible target of the treatment of the achondroplasia.  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