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   1476篇
  免费   187篇
  国内免费   75篇
耳鼻咽喉   5篇
儿科学   23篇
妇产科学   9篇
基础医学   169篇
口腔科学   43篇
临床医学   222篇
内科学   354篇
皮肤病学   48篇
神经病学   83篇
特种医学   112篇
外科学   122篇
综合类   89篇
预防医学   112篇
眼科学   8篇
药学   166篇
中国医学   1篇
肿瘤学   172篇
  2021年   18篇
  2020年   9篇
  2019年   19篇
  2018年   23篇
  2017年   19篇
  2016年   27篇
  2015年   20篇
  2014年   24篇
  2013年   61篇
  2012年   64篇
  2011年   59篇
  2010年   56篇
  2009年   50篇
  2008年   41篇
  2007年   106篇
  2006年   70篇
  2005年   60篇
  2004年   57篇
  2003年   54篇
  2002年   56篇
  2001年   48篇
  2000年   58篇
  1999年   43篇
  1998年   32篇
  1997年   36篇
  1996年   35篇
  1995年   37篇
  1994年   15篇
  1993年   29篇
  1992年   29篇
  1991年   30篇
  1990年   25篇
  1989年   38篇
  1988年   27篇
  1987年   28篇
  1986年   30篇
  1985年   31篇
  1984年   15篇
  1983年   23篇
  1982年   21篇
  1981年   15篇
  1980年   14篇
  1979年   10篇
  1978年   17篇
  1977年   11篇
  1976年   12篇
  1975年   19篇
  1974年   11篇
  1973年   9篇
  1971年   8篇
排序方式: 共有1738条查询结果,搜索用时 15 毫秒
971.
Non-fermentative Gram-negative bacteria (Pseudomonas aeruginosa, Burkholderia cepacia, Stenotrophomonas maltophilia and Acinetobacter spp.) are intrinsically less susceptible to many antimicrobial agents. Two-drug combinations have been used to treat infections caused by less susceptible pathogens. In this study, the antibacterial activity of garenoxacin (GARX) with non-quinolones was examined. The non-quinolones evaluated were cefepime (CEPI), imipenem (IMIP), aztreonam (AZTR), piperacillin-tazobactam (PIPC/TZ), amikacin (AMK), ceftazidime (CTAZ), trimethoprim-sulphamethoxazole (TMP/SMX) and ticarcillin-clavulanate (TICC/CA). Synergism was determined by time-kill analysis using GARX (at 2 x its MIC, not to exceed 4 mg/l) and the second drug (at 1 x MIC, not to exceed its susceptible MIC breakpoint), and is defined as > or = 2 log(10) enhanced killing at 24 h with the combination. Partial synergy is defined as > or = 1.5 log(10) but < 2 log(10) enhanced killing with the drug combination. Synergy/partial synergy was observed most often with GARX plus: CEPI, AZTR, PIPC/TZ, IMIP (five strains each) or AMK (four strains) vs. eight P. aeruginosa; CTAZ, AZTR (five strains each) vs. six B. cepacia; TICC/CA (six strains), CEPI, CTAZ or AMK (five strains each) vs. eight S. maltophilia; and CEPI, AMK (three strains each) or CTAZ, TICC/CA (two strains each) vs. four Acinetobacter spp. In conclusion, synergistic killing was observed frequently with GARX plus a non-quinolone bactericidal agents against non-fermentative Gram-negative bacteria, including strains intermediately susceptible/resistant to one or both agents.  相似文献   
972.
Because small intestine submucosa (SIS) is a bioscaffold for tissue regeneration, we describe a method to analyze the material for growth peptides and for structural molecules. Immunofluorescence methods are described for relative quantification of abundant structural proteins. Additionally, a quantitative technique for comparison of the content of less abundant proteins in SIS was developed using the tyramide signal amplification (TSA) system that is applicable to paraffin-preserved tissue blocks. Frozen sections generally shredded when cut thinly enough to permit entry and washout of reagents. Five micrometer sections cut from paraffin blocks were immunolabeled for collagen, heparan sulfate proteoglycans (HSPG), FGF2, TGFbeta, and VEGF. Images of tissue sections were acquired by a linear image camera and quantified by densitometry after thresholding the signal to minimize nonspecific fluorescence. Immunohistochemistry was used to confirm the immunofluorescence methods. HSPG was widely distributed but concentrated in vessels. FGF2 was distributed diffusely and was associated with fibrous structures. VEGF was distributed mainly around vessels. TGFbeta was barely detectable above background. Collagen fibrils were distinctly present, and with a two-color fluorescence system, the distribution of components relative to collagen can be assessed. The anatomic structure of SIS is likely to play an important role in the regeneration of tissues, and factors in remnant vessels may facilitate penetration of the matrix along these avenues.  相似文献   
973.
974.
Bonner L 《Nursing times》2004,100(29):38-42
Deep vein thrombosis can have serious long-term consequences and can result in fatal complications. Many patients are at increased risk of DVT, but knowledge of common risk factors and an awareness of appropriate prophylactic measures can help prevent its occurrence. An ability to recognise common clinical signs and symptoms, together with an understanding of diagnosis and treatment, benefits the nursing management of DVT.  相似文献   
975.
976.
977.
978.
AIM OF THE PAPER: To examine the application of the decision tree approach to collaborative clinical decision-making in mental health care in the United Kingdom (UK). BACKGROUND: While this approach to decision-making has been examined in the acute care setting, there is little published evidence of its use in clinical decision-making within the mental health setting. The complexities of dual diagnosis (schizophrenia and substance misuse in this case example) and the varied viewpoints of different professionals often hamper the decision-making process. This paper highlights how the approach was used successfully as a multiprofessional collaborative approach to decision-making in the context of British community mental health care. DESIGN: A selective review of the relevant literature and a case study application of the decision tree framework. CONCLUSIONS: The process of applying the decision tree framework to clinical decision-making in mental health practice can be time consuming and client inclusion within the process is not always appropriate. The approach offers a method of assigning numerical values to support complex multiprofessional decision-making as well as considering underpinning literature to inform the final decision. Use of the decision tree offers a common framework that can assist professionals to examine the options available to them in depth, while considering the complex variables that influence decision-making in collaborative mental health practice. Use of the decision tree warrants further consideration in mental health care in terms of practice and education.  相似文献   
979.
There is limited research of smoking cessation following diagnosis of lung cancer. This prospective study assessed cigarette smoking behavior among 226 patients (142 males, 84 females) prior to, at the time of, and after the diagnosis of unresectable stage IIIA/IIIB non-small cell lung cancer and entry into a phase III trial examining combined thoracic radiation therapy and chemotherapy. Their mean +/-S.D. age was 62.7+/-9.4 years and 95.6% were Caucasian. Of 215 patients with a history of cigarette smoking, 69% (148/215) stopped smoking prior to entry in the trial, 9% (20/215) stopped smoking at some point during the course of the trial, 11% (24/215) continued smoking throughout the trial, 7% (16/215) were smoking at baseline but did not report subsequent smoking status, and smoking status at study entry was missing for the remaining patients. The majority of lung cancer patients were able to stop smoking. A notable subset of patients continued smoking despite diagnosis of lung cancer, enrollment in a clinical trial, treatment-related toxicity, and encouragement from clinicians to stop smoking. Smoking cessation interventions are needed for lung cancer patients who continue to smoke.  相似文献   
980.
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