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   2772篇
  免费   142篇
  国内免费   9篇
耳鼻咽喉   15篇
儿科学   20篇
妇产科学   41篇
基础医学   300篇
口腔科学   77篇
临床医学   141篇
内科学   665篇
皮肤病学   5篇
神经病学   78篇
特种医学   339篇
外科学   347篇
综合类   6篇
预防医学   35篇
眼科学   4篇
药学   104篇
中国医学   2篇
肿瘤学   744篇
  2023年   10篇
  2022年   19篇
  2021年   49篇
  2020年   18篇
  2019年   23篇
  2018年   33篇
  2017年   24篇
  2016年   37篇
  2015年   55篇
  2014年   67篇
  2013年   67篇
  2012年   122篇
  2011年   122篇
  2010年   74篇
  2009年   71篇
  2008年   139篇
  2007年   150篇
  2006年   146篇
  2005年   118篇
  2004年   130篇
  2003年   146篇
  2002年   155篇
  2001年   85篇
  2000年   96篇
  1999年   100篇
  1998年   41篇
  1997年   29篇
  1996年   41篇
  1995年   34篇
  1994年   36篇
  1993年   19篇
  1992年   67篇
  1991年   57篇
  1990年   74篇
  1989年   60篇
  1988年   57篇
  1987年   52篇
  1986年   41篇
  1985年   33篇
  1984年   23篇
  1983年   28篇
  1982年   12篇
  1981年   15篇
  1980年   15篇
  1979年   20篇
  1978年   11篇
  1977年   19篇
  1976年   13篇
  1974年   12篇
  1971年   10篇
排序方式: 共有2923条查询结果,搜索用时 15 毫秒
1.
We describe a case of 41-year-old Japanese man with Crohn's ileocolitis and cytomegalovirus infection, confirmed by histology of ileal ulcers. Although his colonoscopic and radiological features resembled those of intestinal tuberculosis, granulomas of typical Crohn's disease were evident on histology of biopsy specimens taken from the duodenum and colon. The lesions remain unchanged even after 1.5 years by oral administration of salazosulphapyridine 3g daily.  相似文献   
2.
3.
4.
5.
MRI of ossification of ligamentum flavum.   总被引:11,自引:0,他引:11  
Magnetic resonance imaging of 28 patients with radiological and/or histopathologically proved ossification of the ligamentum flavum (OLF) was reviewed. The locations of OLF were cervical (n = 4), thoracic (n = 22), and lumbar (n = 2). On T1- and T2-weighted images, OLF demonstrated low signal intensity. Areas of high or intermediate signal intensity within the OLF on T1-weighted images were observed in three cases and were interpreted to be due to fat infiltration. In six cases, high intensity areas in the spinal cord caused by compressing OLF were demonstrated on T2-weighted images. Gadolinium-diethylenetriamine pentaacetic acid, which was used in four cases, showed cord enhancement at the level of compression by OLF in three cases.  相似文献   
6.
To evaluate the correlation between the histological grade and the prognosis, we reviewed 100 cases of prostatic cancer according to the Japanese General Rules of Prostatic Cancer (JGRPC) and Gleason grading system. The study led to the following results: (1) There was a close relation between the JGRPC grade and Gleason score (GS). (2) The JGRPC grade and Gleason score were equally concerned with the clinical stage. (3) There were significant differences in survival rate between well and moderately, well and poorly differentiated groups by the JGRPC grading system, and between GS 2-4 and GS 5-7, GS 2-4 and GS 8-10 groups by Gleason score. (4) In proportion to the JGRPC grade, the cancer death rate increased linearly in each stage. (5) When the patients were grouped according to their JGRPC grades of main lesion and accompanied lesion, the cancer death rate increased in the cases with lower differentiated elements. We conclude that the JGRPC grading system is easily comprehensible, and equal with the Gleason grading system to predict the prognosis of prostatic cancer.  相似文献   
7.
Low-dose γ-irradiation of mouse embryonic fibroblast C3D2F1 3T3-a cells caused Gl arrest along with G2 arrest and inhibition of replicative DNA synthesis. When the cells were cultured in the presence of inhibitors of poly(ADP-ribose) polymerase [EC 2.4.2.30], such as 3-aminobenzamide, benzamide and luminol, Gl arrest of C3D2F1 3T3-a cells was suppressed and enhancement of G2 arrest was observed. In contrast, 3-aminobenzoic acid, a non-inhibitory analog of 3-aminobenzamide, did not suppress Gl arrest following γ-irradiation. These results suggest that the poly(ADP-ribosyDation reaction is critical for the pathway of Gl arrest and is also involved in the pathway of G2 arrest.  相似文献   
8.
9.
10.
Patients with Peutz-Jeghers syndrome (PJS) are known to be at risk of gastric cancer (GC), and the STK11 gene is a susceptibility gene for PJS. However, as no cases of PJS with GC in which a STK11 germline mutation has been identified have ever been reported and other susceptibility genes have also been suggested to be involved in PJS, the relation between STK11 germline mutations and GC in PJS is still unknown. In this study, we used sequencing analysis to investigate the STK11, CDH1, and TP53 loci for a germline mutation in two siblings with PJS with primary GC. A novel type of the STK11 germline mutation, c.890delG, encoding a truncated protein (p.Arg297fsX38) was identified, but no germline mutations of the CDH1 and TP53 genes were detected. No inactivation of the wild-type allele by somatic mutation or chromosomal deletion or hypermethylation at the 5'-CpG site of STK11 was detected in the GC. This is the first report of a STK11 germline mutation in a PJS patient with GC and should contribute to establishing correlations between the STK11 germline mutations and GC in PJS patients.  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