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   910篇
  免费   42篇
  国内免费   14篇
耳鼻咽喉   24篇
儿科学   21篇
妇产科学   37篇
基础医学   83篇
口腔科学   38篇
临床医学   76篇
内科学   158篇
皮肤病学   13篇
神经病学   24篇
特种医学   94篇
外科学   168篇
综合类   24篇
一般理论   1篇
预防医学   50篇
眼科学   26篇
药学   95篇
中国医学   2篇
肿瘤学   32篇
  2022年   16篇
  2021年   32篇
  2020年   16篇
  2019年   19篇
  2018年   27篇
  2017年   13篇
  2016年   19篇
  2015年   23篇
  2014年   15篇
  2013年   24篇
  2012年   36篇
  2011年   37篇
  2010年   30篇
  2009年   36篇
  2008年   30篇
  2007年   49篇
  2006年   35篇
  2005年   10篇
  2004年   24篇
  2003年   23篇
  2002年   20篇
  2001年   17篇
  2000年   14篇
  1999年   17篇
  1998年   21篇
  1997年   16篇
  1996年   9篇
  1995年   12篇
  1994年   10篇
  1993年   10篇
  1992年   14篇
  1991年   17篇
  1990年   9篇
  1989年   13篇
  1988年   11篇
  1987年   16篇
  1986年   10篇
  1985年   10篇
  1984年   10篇
  1982年   11篇
  1981年   9篇
  1979年   13篇
  1976年   12篇
  1975年   10篇
  1974年   10篇
  1973年   14篇
  1972年   14篇
  1971年   11篇
  1970年   8篇
  1969年   11篇
排序方式: 共有966条查询结果,搜索用时 31 毫秒
101.
The objective of this study was to determine the chemopreventive effects of sarcophine-diol (SD) on 7,12-dimethylbenz(a)anthracene initiated and 12-O-tetradecanoylphorbol-13-acetate promoted skin tumor development in mice and its possible mechanisms of action. SD pretreatment significantly (P<0.05) decreased skin papilloma development during promotion phase. SD significantly (P<0.05) increased caspase-3 and decreased cyclooxygenase-2 during initiation phase or promotion phase. SD significantly (P<0.05) increased caspase-8 during promotion phase. SD resulted in a 95% reduction in 12-O-tetradecanoylphorbol-13-acetate-induced DNA synthesis. SD could be an effective chemopreventive agent for skin cancer by enhancing apoptosis and decreasing cell proliferation.  相似文献   
102.
103.
Coccidioidomycosis has been reported in almost every tissue of the human body. The gastrointestinal tract and breast have been uniquely spared from this fungal infection. Despite the exceedingly large number of screening mammographies that are performed every year, to our knowledge subcutaneous breast tissue involvement as the sole presentation or of secondary spread of coccidioidomycosis has not been reported. We describe a patient who showed an unusual manifestation of a coccidioidal breast nodule simulating a neoplasm. The patient had been transiently immunosuppressed by prednisone therapy for presumptive temporal arteritis.  相似文献   
104.
105.
Colposcopic examination was done in 189 successive parturients within 6-48 h of delivery for evidence of type, site, and extent of cervical trauma and its relation to various obstetric factors. There was trauma in 66% of cases, as erosion in 79%, as laceration in 56%, as bruising in 30%, and as yellow areas in 17%. In about two-thirds of cases, the diameter of cervical erosion, or the length of laceration did not exceed 5 mm and 81% of lacerations were of first degree. Cervical injury was significantly more frequent in primiparae, in the anterior cervical lip, in occipito-posterior positions, and with premature rupture of membranes. In 117 parturients with cervical injury another colposcopic examination was done 6-8 weeks postpartum. In 8% there was residual cervical damage.  相似文献   
106.
107.
2-[(4-Oxo-4,5-dihydrothiazol-2-yl)methyl]-1H-benzimidazole ( 2 ) was prepared through the reaction of 2-cyanomethyl-1H-benzimidazole ( 1 ) with thioglycolic acid. The syntheses of its arylidene 3 and diazo-coupled compounds 5 and the cyclization of the aforementioned thiazolylbenzimidazole to benzimidazolylthiazolo[3,2-a]pyridines 8 were also performed. The prepared compounds were screened for their in-vitro antibacterial, antifungal, anti-HIV, and anticancer activities: they show promising antifungal activity.  相似文献   
108.
Cimetidine has been determined in the presence of its acid-induced degradation products using a second derivative (D2-) spectrophotometric method (method I) or a colorimetric method (method II). The former is based on D2-value measurement at 216 nm, whilst the latter depends on charge-transfer complexation with dichlorophenol-indophenol. The two methods are proved to be stability indicating, since plots of log C% versus time were linear. The application to cimetidine determination in tablets and ampoules gave good results.  相似文献   
109.
β-锗代-α-氨基酸衍生物的合成及抗肿瘤活性   总被引:5,自引:0,他引:5  
自六十年代初期发现羧乙基锗倍半氧化物(Ge—132)广泛的生物活性以来,已有许多相应的有机锗化合物被发现,在抗肿瘤活性方面,因有毒性较低、抗瘤谱广等一系列优点而引起人们广泛的兴趣,但由于活性较低影响了应用及发展,据文献报道,有机锗倍半氧  相似文献   
110.
This study aimed to assess the revascularisation potential of necrotic mature teeth in a dog model following different protocols. Periapical infection was induced in 54 mature premolars. Teeth were distributed into seven groups: (1) Double‐antibiotic‐paste/Blood clot, (2) Ciprofloxacin/collagen, (3) Double‐antibiotic‐paste/Collagen, (4) Modified Tri‐antibiotic‐paste /collagen, (5) Ciprofloxacin/Gelfoam, (6) Double‐antibiotic‐paste/Gelfoam, and (7) Modified Triantibiotic‐ paste/Gelfoam. Positive and negative controls included infected and healthy teeth, respectively, (n = 12 roots/group). Canals were apically shaped to size 0.6 mm then disinfected for 1 month. Intra‐canal bleeding was induced then scaffolds were applied for another month. Teeth and supporting bone were surgically sampled. Tissues were histologically scored and vimentin immuno‐intensity was estimated. Ciprofloxacin and Double‐antibiotic paste/Collagen resulted in significantly better corono‐apical tissue ingrowths, vascularity, cementum formation and significantly lower inflammatory extents (P < 0.05).These groups also showed significantly higher Vimentin intensities, (P < 0.05). The applied protocols revascularised necrotic mature canals and reduced inflammation particularly in the Ciprofloxacin/collagen and Double‐antibiotic‐paste/collagen groups.  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