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   223685篇
  免费   10969篇
  国内免费   2096篇
耳鼻咽喉   2702篇
儿科学   5998篇
妇产科学   5054篇
基础医学   30301篇
口腔科学   6693篇
临床医学   15793篇
内科学   47533篇
皮肤病学   5681篇
神经病学   17032篇
特种医学   5453篇
外国民族医学   7篇
外科学   25787篇
综合类   6939篇
现状与发展   3篇
一般理论   37篇
预防医学   24806篇
眼科学   5799篇
药学   18062篇
  53篇
中国医学   2960篇
肿瘤学   10057篇
  2023年   1533篇
  2022年   2478篇
  2021年   5391篇
  2020年   3373篇
  2019年   4785篇
  2018年   6931篇
  2017年   4821篇
  2016年   4607篇
  2015年   5657篇
  2014年   6854篇
  2013年   9436篇
  2012年   15267篇
  2011年   15880篇
  2010年   8886篇
  2009年   6991篇
  2008年   12449篇
  2007年   13073篇
  2006年   12206篇
  2005年   11548篇
  2004年   10267篇
  2003年   9593篇
  2002年   8938篇
  2001年   5388篇
  2000年   5829篇
  1999年   4543篇
  1998年   1095篇
  1997年   806篇
  1992年   2378篇
  1991年   2119篇
  1990年   2099篇
  1989年   1786篇
  1988年   1693篇
  1987年   1591篇
  1986年   1631篇
  1985年   1540篇
  1984年   1117篇
  1983年   959篇
  1979年   1273篇
  1978年   860篇
  1977年   832篇
  1975年   912篇
  1974年   1155篇
  1973年   1192篇
  1972年   1133篇
  1971年   1095篇
  1970年   1024篇
  1969年   1107篇
  1968年   1115篇
  1967年   992篇
  1966年   895篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
42.
Congenital absence of the portal vein (CAPV) is a rare malformation of the splanchnic venous system. Although CAPV is usually detected in the pediatric age group, our patient was a 35-year-old woman. She had been diagnosed with CAPV in 1996 when she was 27 years old. In 1998, she was placed on hemodialysis due to chronic renal failure. After several episodes of encephalopathy in 2002, liver transplantation (LT) was recommended to her and her family. Since there was no suitable living donor candidate, she was put on the waiting list for a deceased donor liver transplant in Japan. In 2004, her ammonia level increased to around 300 microg/dl, and she went into a coma lasting for three days. After recovering from this event, she underwent a living domino transplantation using a whole liver donated by a familial amyloid polyneuropathy (FAP) patient. Her portal vein, which had drained directly into the inferior vena cava (IVC), was transected together with a cuff of the IVC wall and anastomosed to the graft liver portal vein in an end-to-end fashion. In conclusion, liver transplantation proved to be a safe and effective way to save this patient and improve her quality of life.  相似文献   
43.
The specific characteristics of genetic data lead to ethical-legal conflicts in the framework of genetic diagnosis. Several international organisations, including UNESCO and the Council of Europe, have enacted rules referring to the use of genetic information. This paper discusses possible legal and ethical criteria that could be used in genetic testing.  相似文献   
44.
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   
45.
46.
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   
47.
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   
48.
49.

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   
50.
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