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   2874篇
  免费   198篇
  国内免费   11篇
耳鼻咽喉   20篇
儿科学   89篇
妇产科学   53篇
基础医学   368篇
口腔科学   12篇
临床医学   277篇
内科学   668篇
皮肤病学   56篇
神经病学   253篇
特种医学   56篇
外科学   367篇
综合类   39篇
预防医学   253篇
眼科学   44篇
药学   238篇
中国医学   11篇
肿瘤学   279篇
  2023年   36篇
  2022年   37篇
  2021年   89篇
  2020年   57篇
  2019年   74篇
  2018年   83篇
  2017年   46篇
  2016年   50篇
  2015年   65篇
  2014年   116篇
  2013年   140篇
  2012年   176篇
  2011年   201篇
  2010年   106篇
  2009年   104篇
  2008年   157篇
  2007年   173篇
  2006年   148篇
  2005年   136篇
  2004年   130篇
  2003年   101篇
  2002年   106篇
  2001年   48篇
  2000年   38篇
  1999年   69篇
  1998年   24篇
  1997年   14篇
  1996年   18篇
  1995年   24篇
  1994年   19篇
  1993年   14篇
  1992年   38篇
  1991年   33篇
  1990年   38篇
  1989年   30篇
  1988年   29篇
  1987年   38篇
  1986年   34篇
  1985年   27篇
  1984年   19篇
  1983年   14篇
  1982年   12篇
  1980年   15篇
  1979年   10篇
  1978年   15篇
  1977年   11篇
  1976年   10篇
  1974年   11篇
  1973年   10篇
  1972年   13篇
排序方式: 共有3083条查询结果,搜索用时 15 毫秒
51.
52.
Peutz-Jeghers syndrome is an autonomic dominant disease characterized by hamartomatous polyps and mucocutaneous hyperpigmentation. We present 16 cases; females were more affected. The most common presenting complaints were of gastrointestinal tract. All polyps found were hamartomatous with general distribution through gastrointestinal tract. Endoscopic polypectomy should be carried out for treatment. Radiologic, endoscopic and histologic studies should be conducted for long-term follow-up, because of high risk of malignancy.  相似文献   
53.
Monitoring airway inflammation by means of induced sputum cell counts seems to improve the management of asthma. We sought to assess whether such monitoring at the end of periods at and away from work combined with the monitoring of PEF could improve the diagnosis of occupational asthma. We enrolled subjects suspected of having occupational asthma. Serial monitoring of PEF was performed during 2 weeks at and away from work. At the end of each period, induced sputum was collected. Specific inhalation challenge was subsequently performed. PEF graphs were interpreted visually by five independent observers. Forty-nine subjects, including 23 with positive specific inhalation challenge, completed the study. The addition of sputum cell counts to the monitoring of PEF increased the specificity of this test, respectively, by 18 (range [r] 13.7-25.5) or 26.8% (r 24.8-30.4) depending if an increase of sputum eosinophils greater than 1 or 2% when at work was considered as significant. The sensitivity increased by 8.2% (r 4.1-13.4) or decreased by 12.3% (r 3.1-24.1) depending on the cutoff value in sputum eosinophils chosen (greater than 1 or 2%, respectively). The addition of sputum cell counts to PEF monitoring is useful to improve the diagnosis of occupational asthma.  相似文献   
54.
55.
Congenital hypofibrinogenemia is a rare bleeding disorder characterized by abnormally low levels of fibrinogen in plasma, generally due to heterozygous mutations in one of the three fibrinogen genes (FGA, FGB, and FGG, coding for Aα, Bβ, and γ chain, respectively). Hypofibrinogenemic patients are usually asymptomatic, whereas individuals bearing similar mutations in the homozygous or compound heterozygous state develop a severe bleeding disorder: afibrinogenemia. The mutational spectrum of these quantitative fibrinogen disorders includes large deletions, point mutations causing premature termination codons, and missense mutations affecting fibrinogen assembly or secretion, distributed throughout the 50-kb fibrinogen gene cluster. In this study, we report the mutational screening of two unrelated hypofibrinogenemic patients leading to the identification of two missense mutations, one hitherto unknown (αCys45Phe), and one previously described (γAsn345Ser). The involvement of αCys45Phe and γAsn345Ser in the pathogenesis of hypofibrinogenemia was investigated by in-vitro expression experiments. Both mutations were demonstrated to cause a severe impairment of intracellular fibrinogen processing, either by affecting half-molecule dimerization (αCys45Phe) or by hampering hexamer secretion (γAsn345Ser).  相似文献   
56.
GOALS: To study the association between tobacco exposure and postoperative clinical recurrence in Crohn's disease patients and quantify the time to clinical relapse following surgical resection. BACKGROUND: It is well accepted that cigarette smoking has a negative impact on postoperative course in Crohn's disease. However, the effect of smoking to hasten clinical recurrence has not been clearly delineated. STUDY: We reviewed medical records of patients undergoing surgical resection for medication-refractory disease within a 5-year period. Patients were followed for a period of 250 weeks. Outcomes were compared between smokers and nonsmokers and stratified by gender. RESULTS: Fifty-nine patients were studied. Sixty-nine percent of smokers versus 23% of nonsmokers had recurrent symptoms (P = 0.02) by the end of the observation period. There was no difference in the mean ages, gender, disease location, use of postoperative medications, or number of postoperative visits (P > 0.09). Smoking was associated with an increased risk of clinical recurrence [odds ratio 2.96 (95% confidence interval, CI 1.5-5.6)]. The time to clinical relapse for smokers was 130 weeks versus 234 weeks in nonsmokers (P < 0.001). CONCLUSION: Smoking is associated with clinical recurrence of Crohn's disease, and the time to clinical recurrence in smokers is shorter. Strategies for smoking cessation are warranted.  相似文献   
57.
58.
Introduction: Lenalidomide, an immunomodulatory agent with unique mechanism of action, represents the cornerstone in the treatment of patients with multiple myeloma (MM) providing rapid and sustained control of the disease with a manageable safety profile.

Areas covered: This review article, synthesizing all available data coming from trials and evaluating the efficacy and safety of lenalidomide in patients with MM, tries to provide to the clinicians with an easy-to-grasp synopsis of recent and clinically meaningful advances on the field.

Expert opinion: Lenalidomide combined with dexamethasone is a safe and effective option for newly diagnosed MM patients ineligible for autologous stem cell transplantation (ASCT). Long-term administration of the agent as continuous treatment for ineligible for ASCT patients or maintenance therapy after ASCT has documented unprecedented progression-free survival improvements, whereas lenalidomide in combination with dexamethasone has shown deep and durable remissions for patients with relapsed and/or refractory disease.  相似文献   
59.
60.
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