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   15252篇
  免费   660篇
  国内免费   73篇
耳鼻咽喉   248篇
儿科学   239篇
妇产科学   208篇
基础医学   1827篇
口腔科学   450篇
临床医学   997篇
内科学   3865篇
皮肤病学   323篇
神经病学   903篇
特种医学   694篇
外科学   2773篇
综合类   75篇
一般理论   2篇
预防医学   459篇
眼科学   146篇
药学   1092篇
中国医学   42篇
肿瘤学   1642篇
  2023年   73篇
  2022年   170篇
  2021年   274篇
  2020年   163篇
  2019年   194篇
  2018年   255篇
  2017年   177篇
  2016年   191篇
  2015年   246篇
  2014年   321篇
  2013年   393篇
  2012年   673篇
  2011年   836篇
  2010年   454篇
  2009年   373篇
  2008年   755篇
  2007年   743篇
  2006年   749篇
  2005年   714篇
  2004年   655篇
  2003年   629篇
  2002年   642篇
  2001年   457篇
  2000年   506篇
  1999年   425篇
  1998年   166篇
  1997年   140篇
  1996年   166篇
  1995年   111篇
  1994年   113篇
  1993年   118篇
  1992年   378篇
  1991年   330篇
  1990年   334篇
  1989年   337篇
  1988年   323篇
  1987年   303篇
  1986年   264篇
  1985年   248篇
  1984年   188篇
  1983年   171篇
  1979年   110篇
  1978年   78篇
  1977年   81篇
  1974年   79篇
  1973年   72篇
  1972年   74篇
  1971年   72篇
  1970年   81篇
  1969年   75篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
Big mitogen-activated protein kinase 1 (BMK1), also known as extracellular signal-regulated kinase 5 (ERK5), is a newly identified member of the mitogen-activated protein (MAP) kinase family. Recently, several studies have suggested that BMK1 plays an important role in the pathogenesis of cardiovascular disease. To clarify the pathophysiological significance of BMK1 in the process of vascular remodeling, we explored the molecular mechanisms of BMK1 activation in vascular smooth muscle cells (VSMCs). From the results of co-immunoprecipitation and immunoblotting analyses, it was found that platelet-derived growth factor (PDGF), a known potent mitogen, activated BMK1 and triggered the Gab1-SHP-2 interaction in rat aortic smooth muscle cells (RASMCs). The abrogation of SHP-2 phosphatase activity by transfection of the SHP-2-C/S mutant suppressed PDGF-stimulated BMK1 activation. Infection with an adenoviral vector expressing dominant-negative MEK5alpha, which can suppress PDGF-stimulated BMK1 activation to the control level, inhibited PDGF-induced RASMC migration. Moreover, we observed an increase of BMK1 activation in injured mouse femoral arteries. From these findings, it is suggested that BMK1 activation leads to VSMC migration induced by PDGF via Gab1-SHP-2 interaction, and that BMK1-mediated VSMC migration may play a role in the pathogenesis of vascular remodeling.  相似文献   
12.
Intravesical instillation of anti-cancer drugs for superficial urinary bladder cancer is generally carried out with the aim of prophylaxis against recurrence and chemotherapy against tumor. But since sensitivity of tumor cells to each anti-cancer drug differs individually, the anti-cancer drug to be used should also be decided individually. We selected a new sensitivity test, ATP-sensitivity-assay, which measures intracellular adenosine triphosphate (ATP) volume by Luciferin-Luciferase reaction, for the decision of the anti-cancer drug. In this paper, we evaluated the direct anti-tumor activity of the drugs that were decided by ATP-sensitivity-assay of intravesical chemotherapy. Six drugs, that are Doxorubicin (ADM), Mitomycin C (MMC), Pirarubicin (THP-ADM), Cytarabine (Ara-C), Bleomycin (BLM) and Cisplatin (CDDP) were tested in this research and size of tumors of six patients reduced to 34-93% after 6 times' installation. A woman got cystitis induced by ADM after 3 times' instillation but instillation was completed. ATP-sensitivity-assay is useful for deciding the anti-cancer drugs for intravesical chemotherapy and prophylaxis for superficial bladder cancer.  相似文献   
13.
14.
15.
16.
Multifactorial analysis on 395 patients revealed important factors which prolong the pyuria after transurethral prostatectomy. They were the age of the patient, anemia and leukocytosis before surgery. These are factors which relate with the defense mechanism of the patient. Local factors, such as the duration of indwelling urethral catheter, the size of the prostate or prostatic bed and preoperative infection, were not so important for prolonging the pyuria after transurethral prostatectomy. The time of the resection and weight of the prostate had an intimate relation each other, and the former was the more important factor. The use of antimicrobials probably controlled these local risk factors, thus making them unimportant in the prolongation of the pyuria after transurethral prostatectomy.  相似文献   
17.
As morphological changes of the native kidneys, the presence of acquired cysts, intra-renal calcification and renal tumor was investigated mainly by ultrasonography and computed tomography in 151 patients with chronic renal failure. 1) Among 140 uremic patients caused by medical diseases. 40 patients had simple cysts, and 37 had acquired cystic disease of the kidneys (ACDK). However 4, uremic patients caused by urological diseases were not seen to be with an acquired cysts. 2) The patients with ACDK were with significantly longer durations of dialysis therapy than those with simple cysts or no cysts. Furthermore, the patients with ACDK were younger than those of the other groups. 3) Intra-renal calcification was more frequently found in patients with cystic disease (simple cyst, ACDK and polycystic disease) than in those without cystic disease with statistic significance. 4) Native kidneys became larger after the occurrence of ACDK. 5) Three cases of renal tumor were found.  相似文献   
18.
After removal of intraductal stones, a 10‐Fr or 7‐Fr pancreatic stent was placed in 16 patients with upstream ductal dilation proximal to a stricture of the main pancreatic duct. Stents were removed after a mean duration of 52.5 days. Nine patients underwent repeated stenting. About one year after removal of the initial stent, when the remaining upstream ductal dilation was found on follow‐up pancreatograms, the next stent was replaced. Repeated stenting improved outflow of pancreatic juice more effectively than one‐time stenting. Correlation between long‐term pain relief without recurrence of intraductal stones and reduction of duct diameter was also shown. Stent occlusion was observed in 14 of 30 stents. Stent occlusion was frequently associated with recurrence of pancreatitis and intraductal stones, and was also associated with morphologic changes in the pancreatic ductal system. Although there were no significant differences between stent patency of the initial stents and that of the next stents, stent patency of 10‐Fr stents was superior to that of 7‐Fr stents. 10‐Fr stents should be removed within 8 weeks and 7‐Fr stents should be removed within 4 weeks for the prevention of stent occlusion. Repeated stenting with short‐term stenting is therefore considered a safe and effective protocol of endoscopic pancreatic stenting.  相似文献   
19.
20.
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