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   1426篇
  免费   138篇
  国内免费   77篇
耳鼻咽喉   6篇
儿科学   28篇
妇产科学   5篇
基础医学   178篇
口腔科学   28篇
临床医学   149篇
内科学   292篇
皮肤病学   152篇
神经病学   112篇
特种医学   95篇
外科学   82篇
综合类   97篇
一般理论   1篇
预防医学   168篇
眼科学   30篇
药学   155篇
中国医学   1篇
肿瘤学   62篇
  2020年   15篇
  2019年   21篇
  2018年   32篇
  2017年   23篇
  2016年   16篇
  2015年   23篇
  2014年   38篇
  2013年   41篇
  2012年   68篇
  2011年   76篇
  2010年   48篇
  2009年   46篇
  2008年   73篇
  2007年   114篇
  2006年   82篇
  2005年   56篇
  2004年   55篇
  2003年   51篇
  2002年   46篇
  2001年   39篇
  2000年   46篇
  1999年   38篇
  1998年   44篇
  1997年   30篇
  1996年   31篇
  1995年   28篇
  1994年   13篇
  1993年   24篇
  1992年   31篇
  1991年   26篇
  1990年   10篇
  1989年   27篇
  1988年   18篇
  1987年   23篇
  1986年   25篇
  1985年   24篇
  1984年   14篇
  1983年   15篇
  1982年   14篇
  1981年   20篇
  1980年   16篇
  1979年   13篇
  1978年   11篇
  1977年   11篇
  1976年   10篇
  1975年   11篇
  1974年   9篇
  1973年   11篇
  1971年   14篇
  1968年   16篇
排序方式: 共有1641条查询结果,搜索用时 328 毫秒
1.
Hypertrophic lichen planus (HLP) is a T‐cell‐mediated process typically presenting with hypertrophic or verrucous plaques on the lower limbs. We report the case of a 24‐year‐old woman with a history of HLP since age 3 years presenting with rapid malignant transformation of one lesion into a large squamous cell carcinoma (SCC). Subsequent examination revealed progressive, widespread metastatic involvement, and the patient ultimately died from her disease. SCC associated with HLP is rare, with a review of the literature revealing fewer than 50 cases. This case highlights the need to be aware of suspicious changes in HLP and to educate patients as to when to be reevaluated.  相似文献   
2.
Kim  SH; Chang  KH; Song  IC; Han  MH; Kim  HC; Kang  HS; Han  MC 《Radiology》1997,204(1):239
  相似文献   
3.
4.
5.
6.
Background: The fabrication of dental prosthesis requires the transfer of interocclusal records from patient's mouth to semiadjustable articulators using different kinds of recording media. Any inaccuracy in these interocclusal records leads to occlusal errors in the final prosthesis. This study was conducted to evaluate the dimensional changes occurring in the interocclusal recording material over a given period of time and the material's resistance to compression during the cast mounting on the articulator.  相似文献   
7.
8.
Antigenic properties of two mutants of Pasteurella haemolytica, strains 59B0071 and 59B0072, that do not produce detectable leukotoxin were investigated. Western blot (immunoblot) analysis with a number of polyclonal sera from animals recovering from pasteurellosis revealed that both mutants secreted a variety of antigens that were also present in cultures of several wild-type strains. These antigens ranged from about 100 to 15 kDa. Mutant strain 59B0071 was found to be totally deficient in leukotoxin, as judged not only by Western blotting but also by cytotoxicity assays with bovine lymphoma (BL-3) cells or bovine polymorphonuclear cells as targets. The mutant strain 59B0071 had normal levels of a secreted sialylglycoprotease, however. When strains were tested for virulence in goat and cattle challenge experiments, a reduction in mortality and lung lesions was observed with the mutant 59B0071 in comparison with results obtained with wild-type strains. These results are consistent with an important role for leukotoxin in P. haemolytica virulence and suggest that leukotoxin-negative mutants may be useful tools in the investigation of other virulence properties involved in P. haemolytica infections.  相似文献   
9.
This study determined the influence of baroreflex sensitivity (BRS) on the rate of urinary sodium excretion and plasma renin activity (PRA) in response to a saline infusion in conscious male rabbits specifically bred for high (Group I; n = 7) and low (Group II; n = 10) BRS and in seven control animals. Only Group II showed significant increases in blood pressure on a chronic high-salt intake. After ensuring that each animal was in sodium balance, a (0.7-0.9%) saline infusion of 3-4 ml/kg per h for 90 min (25% daily sodium intake for each rabbit) was given and urine collected at 15-min intervals via a bladder catheter. No differences were found in control urine volumes, urinary sodium or PRA. Group I excreted over 50% of the sodium load and Group II less than 20% within 90 min. PRA fell by more than 30% within 30 min in six Group I rabbits but decreased by less than 30% or increased in Group II. In the control animals, sodium excretion rates and PRA suppression were also much greater in those with high BRS. A highly significant correlation (r = 0.808, P less than 0.01) was found between the per cent of the sodium load excreted and BRS. It is suggested that the delayed sodium excretion and blood pressure elevation in salt-sensitive subjects may be due to a genetic impairment in baroreflex control of renal sympathetic nerve activity.  相似文献   
10.
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