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   617篇
  免费   45篇
耳鼻咽喉   18篇
儿科学   46篇
妇产科学   16篇
基础医学   75篇
口腔科学   15篇
临床医学   62篇
内科学   117篇
皮肤病学   31篇
神经病学   30篇
特种医学   86篇
外科学   46篇
综合类   22篇
预防医学   17篇
眼科学   11篇
药学   43篇
中国医学   1篇
肿瘤学   26篇
  2022年   2篇
  2021年   5篇
  2020年   7篇
  2019年   3篇
  2018年   4篇
  2017年   9篇
  2016年   11篇
  2015年   9篇
  2014年   16篇
  2013年   29篇
  2012年   13篇
  2011年   10篇
  2010年   27篇
  2009年   30篇
  2008年   20篇
  2007年   15篇
  2006年   21篇
  2005年   17篇
  2004年   21篇
  2003年   19篇
  2002年   15篇
  2001年   10篇
  2000年   5篇
  1999年   9篇
  1998年   23篇
  1997年   42篇
  1996年   31篇
  1995年   20篇
  1994年   23篇
  1993年   21篇
  1992年   13篇
  1991年   5篇
  1990年   9篇
  1989年   28篇
  1988年   14篇
  1987年   12篇
  1986年   14篇
  1985年   15篇
  1984年   8篇
  1982年   3篇
  1981年   4篇
  1980年   6篇
  1979年   2篇
  1978年   7篇
  1977年   11篇
  1976年   6篇
  1975年   4篇
  1974年   2篇
  1973年   2篇
  1971年   2篇
排序方式: 共有662条查询结果,搜索用时 89 毫秒
11.
12.
13.
创伤病人的手术与焦虑状态调查   总被引:6,自引:0,他引:6  
采用状态——特质焦虑问卷及10项躯体性焦虑测试题,对40例外科创伤病人手术前后的焦虑状态调查显示:术前状态焦虑量表评分显著高于术后;术前躯体性焦虑评分显著高于术后;高特质焦虑评分亚组与低特质焦虑评分亚组术前状态焦虑评分无显著差异,但术后则前者显著高于后者;急诊手术者手术前后状态焦虑评分显著高于择期手术者。  相似文献   
14.
DFNA54, a third locus for low-frequency hearing loss   总被引:1,自引:0,他引:1  
Nonsyndromic hereditary hearing impairment (NSHHI) is a highly heterogeneous disorder with more than 90 loci mapped, of which nearly one-half of the responsible genes are identified. In dominant NSSHI hearing loss is typically biased towards the high frequencies while low-frequency hearing loss is unusual. Only two NSHHI loci, DFNA1 and DFNA6/14/38, are associated with predominantly low- frequency loss. We mapped the loci harboring the gene responsible for autosomal dominant low-frequency hearing loss in a multigenerational family. The pedigree of a Swiss family with low-frequency hearing loss was established. Using genomic DNA, DFNA1 and DFNA6/14/38 were excluded by linkage analysis or by direct sequencing of the responsible gene. Genome-wide linkage analysis was performed using commercially available microsatellite markers. Two-point linkage analysis demonstrated linkage to chromosome 5q31, the locus for DFNA15, with a lod score of 6.32 at recombination fraction =0 for marker D5S436. Critical recombinations were seen at markers D5S1972 and D5S410. Sequencing of the corresponding gene POU4F3 yielded no pathogenic mutation segregating with the affected members. In addition to Wolfram syndrome gene 1 (DFNA6/14/38) and diaphanous (DFNA1) there is evidence for a third gene involved in low-frequency hearing loss located at DFNA15. Because of the differences in auditory phenotype and the absence of pathogenic mutation in the coding region of POU4F3 it is likely that there is a second gene in 5q31, designated DFNA54, associated with NSHHI.  相似文献   
15.
16.
The allelic frequency of the gene for the K variant of butyrylcholinesterase (BCHE-K) was 0.17 in 74 subjects with late-onset (age > 65 years) histopathologically diagnosed Alzheimer's disease (AD), which was higher than the frequencies in 104 elderly control subjects (0.09), in 14 early-onset cases of confirmed AD (0.07) and in 29 confirmed cases of other dementia (0.10). The association of BCHE-K with late-onset AD was limited to carriers of the epsilon 4 allele of the apolipoprotein E gene (APOE), among whom the presence of BCHE-K gave an odds ratio of confirmed late-onset AD of 6.9 (95% C.I. 1.65-29) in subjects > 65 years and of 12.8 (1.9-86) in subjects > 75 years. In APOE epsilon 4 carriers over 75 years, only 1/22 controls, compared with 10/24 confirmed late-onset AD cases, had BCHE-K. We suggest that BCHE-K, or a nearby gene on chromosome 3, acts in synergy with APOE epsilon 4 as a susceptibility gene for late-onset AD.   相似文献   
17.
18.

Background  

The purpose of the present investigation was to determine if the salivary counts of 40 common oral bacteria in subjects with an oral squamous cell carcinoma (OSCC) lesion would differ from those found in cancer-free (OSCC-free) controls.  相似文献   
19.
Haegele  AD; Wolfe  P; Thompson  HJ 《Carcinogenesis》1998,19(7):1319-1321
Ionizing radiation is a carcinogen that induces oxidative DNA damage. 8- Hydroxy-2'-deoxyguanosine (8-OHdG) is a relatively abundant, mutagenic lesion that is widely regarded as a reliable index of oxidative DNA damage. The purpose of this study was to examine the effects of X- radiation on levels of 8-OHdG in the context of an experimental model for breast cancer in which chronic radiation exposure has been shown to be carcinogenic in Sprague-Dawley rats. A secondary objective of this study was to determine if the use of phenol during DNA isolation affected the concentration of 8-OHdG subsequently measured. Our results indicate that a profoundly carcinogenic dose of radiation induced a small but significant increase in 8-OHdG concentration in mammary gland DNA, and that the use of a phenol-based versus a salt-based method of DNA isolation had no significant impact on the levels of 8-OHdG detected in either control or irradiated tissue.   相似文献   
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