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   2268252篇
  免费   177593篇
  国内免费   4079篇
耳鼻咽喉   31748篇
儿科学   74969篇
妇产科学   64735篇
基础医学   322056篇
口腔科学   65702篇
临床医学   197616篇
内科学   445746篇
皮肤病学   48533篇
神经病学   183233篇
特种医学   90953篇
外国民族医学   767篇
外科学   348437篇
综合类   54448篇
现状与发展   3篇
一般理论   768篇
预防医学   173211篇
眼科学   52600篇
药学   168832篇
  3篇
中国医学   4290篇
肿瘤学   121274篇
  2018年   21553篇
  2016年   18694篇
  2015年   21537篇
  2014年   30019篇
  2013年   46155篇
  2012年   62190篇
  2011年   65721篇
  2010年   39083篇
  2009年   37432篇
  2008年   62941篇
  2007年   66585篇
  2006年   67468篇
  2005年   65686篇
  2004年   64334篇
  2003年   61667篇
  2002年   60561篇
  2001年   104151篇
  2000年   107724篇
  1999年   91544篇
  1998年   25223篇
  1997年   23049篇
  1996年   22863篇
  1995年   22044篇
  1994年   20759篇
  1993年   19678篇
  1992年   74848篇
  1991年   72465篇
  1990年   70847篇
  1989年   68626篇
  1988年   63755篇
  1987年   62873篇
  1986年   60067篇
  1985年   57734篇
  1984年   43343篇
  1983年   37106篇
  1982年   22000篇
  1981年   19514篇
  1980年   18442篇
  1979年   40878篇
  1978年   28532篇
  1977年   24006篇
  1976年   22667篇
  1975年   24306篇
  1974年   29542篇
  1973年   28404篇
  1972年   26276篇
  1971年   24609篇
  1970年   22955篇
  1969年   21524篇
  1968年   20000篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
The author describes a concept of automobilisation of the cervical spine and suboccipital joints. The well known biomechanic peculiarities of cervical spine are transformed in a therapeutic setting to allow a form of automobilisation within a closed system of head and underlying base. The so resulting new patterns of movement – the so-called “advanced movement”– differ from those usually exercised. Slow motion moving and low strength efforts are resulting in mobilisation of important vertebral and soft tissue structures.  相似文献   
993.
Prat  F. 《Acta endoscopica》2002,32(2):507-510
Acta Endoscopica - L’hémorragie iatrogène en endoscopie digestive reste pour l’essentiel l’apanage des techniques de résection tumorale et de la...  相似文献   
994.
BACKGROUND: The risk for allergic reactions depends on the sensitivity of individuals and the quantities of offending food ingested. The sensitivity varies among allergic individuals, as does the threshold dose of a food allergen capable of inducing an allergic reaction. OBJECTIVE: This study aimed at determining the distribution of minimum provoking doses of hazelnut in a hazelnut-allergic population. METHODS: Thirty-one patients with a history of hazelnut-related allergic symptoms, a positive skin prick test to hazelnut and/or an elevated specific IgE level, were included. Double-blind, placebo-controlled food challenges (DBPCFC) were performed with seven increasing doses of dried hazelnut (1 mg to 1 g hazelnut protein) randomly interspersed with seven placebo doses. RESULTS: Twenty-nine patients had a positive challenge. Itching of the oral cavity and/or lips was the first symptom in all cases. Additional gastrointestinal symptoms were reported in five patients and difficulty in swallowing in one patient. Lip swelling was observed in two patients, followed by generalized urticaria in one of these. Threshold doses for eliciting subjective reactions varied from a dose of 1 mg up to 100 mg hazelnut protein (equivalent to 6.4-640 mg hazelnut meal). Extrapolation of the dose-response curve showed that 50% of our hazelnut-allergic population will suffer from an allergic reaction after ingestion of 6 mg (95% CI, 2-11 mg) of hazelnut protein. Objective symptoms were observed in two patients after 1 and 1,000 mg, respectively. CONCLUSION: DBPCFCs demonstrated threshold doses in half of the hazelnut-allergic patients similar to doses previously described to be hidden in consumer products. This stresses the need for careful labelling and strategies to prevent and detect contamination of food products with hazelnut residues.  相似文献   
995.
996.
Polyploidization and centrosome hyperamplification in inflammatory bronchi   总被引:1,自引:0,他引:1  
OBJECTIVE AND DESIGN: Inflammatory and tumorous bronchi were screened in order to obtain new tumor relevant cytogenetic parameters. MATERIAL OR SUBJECTS: Bronchial cells of 32 patients were cultivated by standard cell culture procedures. METHODS: Tetraploidy and aneuploidy was determined by enumeration of chromosome 7 and 8 versus the number of centrosomes. The resulting data were correlated with histopathological data. RESULTS: Tetra- and aneuploidy of epithelial cells were detectable in 76% of tumor cell cultures, 75% of high grade inflammatory tissues and 40% of non- and low grade-inflammatory tissues. Additionally, we observed centrosome hyper-amplification and multipolar mitoses not only in the tumor but also in the early stages of inflammation. CONCLUSION: Inflammatory bronchi already show tumor-specific features and may consequently represent the preliminary genetic stage of cancer development in bronchi.  相似文献   
997.
Vibrio cholerae was isolated from the blood cultures of a neutropenic patient treated with chemotherapy for non-small-cell lung cancer. Attempts to isolate Vibrio spp. from a rectal swab and stool were unsuccessful. Piperacillin/tazobactam treatment resulted in eradication of the microorganism from the patient's blood. Although Vibrio spp. have occasionally been the source of infection in immunocompromised patients, this report describes the first case of non-0:1 Vibrio cholerae bacteremia in a neutropenic patient with a solid tumour. Electronic Publication  相似文献   
998.
The in vitro activities of povidone iodine, potassium peroxymonosulfate, and dimethyldidecylammonium chloride were investigated against 379 nosocomial isolates of Staphylococcus aureus and Pseudomonas aeruginosa responsible for surgical wound infections in patients operated on between July 1995 and June 2001. Overall, the isolates were inhibited by the antiseptics at concentrations below those used routinely. In spite of increasing resistance to the various antibiotics used to treat surgical wound infections, no significant variation in the susceptibility to antiseptics was demonstrated during this 6-year study. Electronic Publication  相似文献   
999.
1000.
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