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   184556篇
  免费   7540篇
  国内免费   455篇
耳鼻咽喉   2400篇
儿科学   5258篇
妇产科学   4220篇
基础医学   26357篇
口腔科学   5726篇
临床医学   11527篇
内科学   39964篇
皮肤病学   4741篇
神经病学   15001篇
特种医学   4750篇
外国民族医学   2篇
外科学   21984篇
综合类   982篇
一般理论   56篇
预防医学   21931篇
眼科学   4788篇
药学   14383篇
中国医学   699篇
肿瘤学   7782篇
  2023年   966篇
  2022年   748篇
  2021年   2912篇
  2020年   1672篇
  2019年   3265篇
  2018年   5536篇
  2017年   3530篇
  2016年   3529篇
  2015年   3921篇
  2014年   4453篇
  2013年   6821篇
  2012年   11555篇
  2011年   12386篇
  2010年   6166篇
  2009年   4512篇
  2008年   9867篇
  2007年   10688篇
  2006年   10104篇
  2005年   9742篇
  2004年   9075篇
  2003年   8475篇
  2002年   8054篇
  2001年   5143篇
  2000年   5691篇
  1999年   4426篇
  1998年   925篇
  1992年   2355篇
  1991年   2114篇
  1990年   2096篇
  1989年   1807篇
  1988年   1725篇
  1987年   1590篇
  1986年   1614篇
  1985年   1550篇
  1984年   1130篇
  1983年   974篇
  1979年   1261篇
  1978年   858篇
  1977年   831篇
  1976年   802篇
  1975年   938篇
  1974年   1172篇
  1973年   1210篇
  1972年   1147篇
  1971年   1122篇
  1970年   1029篇
  1969年   1112篇
  1968年   1136篇
  1967年   1005篇
  1966年   895篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
Due to limited aqueous solubility of dorzolamide at physiologic pH, the pH of Trusopt eye drops (cont. 2% dorzolamide) has to be kept at about 5.65, and to increase the topical bioavailability of the drug from Trusopt the contact time of the drug with the eye surface is increased by increasing the viscosity of the eye drops to 100 cps. This low pH and high viscosity can lead to local irritation. In this study, dorzolamide hydrochloride was formulated as 2% and 4% low viscosity solutions (viscosity 3 to 5 cps) containing randomly methylated beta-cyclodextrin at pH 7.45. These formulations were evaluated in rabbits. The animals were sacrificed at various time points after topical administration of the drug and the dorzolamide concentration determined in the different parts of the eye. Trusopt was used as a reference standard. The topical availability of dorzolamide from the cyclodextrin-containing eye drops appeared to be comparable to that from Trusopt and the drug reached retina and optic nerve to give measurable concentrations for at least 8 h after administration of the eye drops.  相似文献   
92.
93.
94.
Gallibacterium anatis (previously named Pasteurella haemolytica-like) is considered a normal inhabitant of genital and upper respiratory tracts of healthy chickens, but it is also associated with different pathological conditions. Secreted metalloproteases from field and reference G. anatis cultures were obtained by methanol precipitation and were characterized. Proteins of molecular mass higher than 100 kDa showing proteolytic activity were observed in 10% polyacrylamide gels copolymerized with 1% bovine casein. They were active at alkaline pH, and inhibited by ethylenediamine tetraacetic acid. Their activity was stable at 50 degrees C, but partially inhibited at 60 degrees C, and totally inhibited at higher temperatures. Secreted proteins were able to degrade chicken IgG after 24 h of incubation, and cross-reacted with a polyclonal antibody against purified protease from Actinobacillus pleuropneumoniae. Secreted metalloproteases could play a role in infections caused by G. anatis.  相似文献   
95.
BACKGROUND: In an attempt to raise the survival of an unselected and representative population of oral and oropharyngeal squamous cell cancer patients, a pilot study of an integrated four-modality treatment was conceived. Final endpoints were compliance, loco-regional control, survival (after complete 5-year follow-up), and a concept of trial assessment using the treatment-dependent prognostic index TPI. PATIENTS: Eighty-seven consecutive patients with histologically proven untreated stages I-IV disease presented in the period between 1997 and 1999 of whom 14 had to be considered uncurable and 73 were fit to be treated with the intention of achieving a cure. METHODS: All patients received one cycle of neoadjuvant intraarterial chemotherapy with 150 mg/m(2) cisplatin (systemically neutralized with sodium thiosulphate), and, if possible, by consecutive treatment applying both surgery of the primary tumour and the neck lymphatics, as well as by adjuvant radiation over 5 weeks (51.3 Gy) plus concurrent chemotherapy (weekly systemic docetaxel 25 mg/m(2)). RESULTS: Ninety per cent of all cases and 96% of the patients treated with curative intention received more than one modality due to study design. Patient non-compliance in the group treated with curative intention has been 18/73 (=25%), and protocol compliance has been 32/73 (=44%). The locoregional control rate for all cases was 71% (62/87 patients) and for the patients treated with curative intention 83.5% (61/73 patients). Thirteen/fourteen non-curable patients died after a mean period of 4 months. After a median observation time of 5 years, the final absolute survival of the unselected population was 53%, and of the patients treated with curative intention 62% (especially, 70% and 50% for patients with operable stages III and IV, respectively). CONCLUSION: The multimodality regimen as presented proved feasible and showed high objective and relative survival rates in comparison with known data from tumour registries of unselected populations. Intra-arterial chemotherapy should be considered a valuable addition to treatment. The potential of survival benefit from this multimodality regimen in comparison with the prognosis index TPI should be investigated in further studies.  相似文献   
96.
97.

Introduction  

This paper presents the results of a study on the psychometric properties of an authorized Spanish version of the McMaster Family Assessment Device, a self-report measure of family functioning.  相似文献   
98.
99.
100.
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