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   1348篇
  免费   188篇
  国内免费   10篇
耳鼻咽喉   15篇
儿科学   114篇
妇产科学   15篇
基础医学   124篇
口腔科学   42篇
临床医学   171篇
内科学   495篇
皮肤病学   11篇
神经病学   39篇
特种医学   166篇
外科学   171篇
综合类   34篇
预防医学   52篇
眼科学   5篇
药学   30篇
中国医学   5篇
肿瘤学   57篇
  2022年   5篇
  2021年   13篇
  2020年   10篇
  2019年   9篇
  2018年   39篇
  2017年   42篇
  2016年   39篇
  2015年   41篇
  2014年   39篇
  2013年   71篇
  2012年   42篇
  2011年   36篇
  2010年   63篇
  2009年   59篇
  2008年   42篇
  2007年   36篇
  2006年   42篇
  2005年   54篇
  2004年   37篇
  2003年   31篇
  2002年   43篇
  2001年   45篇
  2000年   36篇
  1999年   21篇
  1998年   66篇
  1997年   61篇
  1996年   61篇
  1995年   52篇
  1994年   29篇
  1993年   42篇
  1992年   28篇
  1991年   29篇
  1990年   36篇
  1989年   26篇
  1988年   30篇
  1987年   34篇
  1986年   20篇
  1985年   13篇
  1984年   14篇
  1983年   17篇
  1982年   8篇
  1981年   17篇
  1980年   10篇
  1979年   6篇
  1978年   3篇
  1977年   11篇
  1976年   13篇
  1975年   7篇
  1974年   3篇
  1973年   4篇
排序方式: 共有1546条查询结果,搜索用时 0 毫秒
991.
992.
993.
994.
Tailgut cysts, also called retro-rectal cystic hamartomas or mucin-secreting cysts, are uncommon vestigial masses. They can become complicated with infection or neoplastic degeneration. Surgery is the only treatment. We report here a case of a tailgut cyst in a 60-year-old female, that was discovered 10 years ago but not investigated.  相似文献   
995.
996.
Allogeneic haemopoietic stem cell transplantation offers a potentially curative treatment option for a wide range of life‐threatening malignant and non‐malignant disorders of the bone marrow and immune system in patients of all ages. With rapidly emerging advances in the use of alternative donors, such as mismatched unrelated, cord blood and haploidentical donors, it is now possible to find a potential donor for almost all patients in whom an allograft is indicated. Therefore, for any specific patient, the transplant physician may be faced with a myriad of potential choices, including decisions concerning which donor to prioritize where there is more than one, the optimal selection of specific umbilical cord blood units and which conditioning and graft‐versus‐host disease prophylactic schedule to use. Donor choice may be further complicated by other important factors, such as urgency of transplant, the presence of alloantibodies, the disease status (homozygosity or heterozygosity) of sibling donors affected by inherited disorders and the cytomegalovirus serostatus of patient and donor. We report UK consensus guidelines on the selection of umbilical cord blood units, the hierarchy of donor selection and the preferred conditioning regimens for umbilical cord blood transplantation, with a summary of rationale supporting these recommendations.  相似文献   
997.
998.
BACKGROUND: Recent studies with infliximab indicate the therapeutic potential of tumour necrosis factor alpha blockade in spondyloarthropathy (SpA). Because defective host defence is implicated in the pathogenesis of SpA, the potential side effects of this treatment due to impact on the antimicrobial defence are a major concern. OBJECTIVE: To report systematically the adverse events seen in a large cohort of patients with SpA treated with infliximab, with special attention to bacterial infections. PATIENTS AND METHODS: 107 patients with SpA were treated with infliximab for a total of 191.5 patient years. All serious and/or treatment related adverse events were reported. RESULTS: Eight severe infections occurred, including two reactivations of tuberculosis and three retropharyngeal abscesses, and six minor infections with clear bacterial focus. One patient developed a spinocellular carcinoma of the skin. No cases of demyelinating disease or lupus-like syndrome were seen. Two patients had an infusion reaction, which, however, did not relapse during the next infusion. Finally, three patients with ankylosing spondylitis developed palmoplantar pustulosis. All patients recovered completely with adequate treatment, and infliximab treatment had to be stopped in only five patients with severe infections. CONCLUSIONS: Although the global safety of infliximab in SpA is good compared with previous reports in rheumatoid arthritis and Crohn's disease, the occurrence of infections such as tuberculosis and retropharyngeal abscesses highlights the importance of careful screening and follow up. Focal nasopharyngeal infections and infection related symptoms, possibly induced by streptococci, occurred frequently, suggesting an impairment of specific host defence mechanisms in SpA.  相似文献   
999.
ObjectiveTo investigate the analgesic activity of methanolic extract of Amaranthus viridis (A. viridis), Amaranthus caudatus (A. caudatus) and Amaranthus spinosus (A. spinosus).MethodsIn this study, the analgesic activity of methanol extracts of all three plants at doses of 200 and 400 mg/kg were investigated by acetic acid-induced writhings test, hot plate test and tail immersion test for mice.ResultsIt was found that all the three plants showed significant pain management effect (P<0.01) at a dose of 400 mg/kg, but showed a less significant effect at a dose of 20 mg/kg in the entire tests used for evaluation of analgesic activities (P<0.05).ConclusionsMethanol extracts of A. viridis, A. caudatus and A. spinosus show potent analgesic activities, and this study provides the scientific proof for their traditional claims.  相似文献   
1000.
OBJECTIVE: Numerous reports of negative effects as well as protective effects of glucocorticoids on articular cartilage convinced us to study the influence of hydrocortisone on aggrecan synthesis of isolated phenotypically stable human articular chondrocytes cultured in two different matrices. METHODS: Macroscopically normal human articular cartilage was obtained from femoral condyles within 24 hours postmortem. Chondrocytes were isolated and cultured in gelled agarose or in alginate. After 14 days in culture, hydrocortisone was added for 5 days at concentrations ranging from 0.005 microgram to 1 mg/ml for the agarose cultures and from 0.005 microgram to 1 microgram/ml for the alginate culture system. Aggrecan synthesis was measured by the incorporation of 35Sulphate, and the proportion of neosynthesized aggrecan that bound to hyaluronan to form aggrecan aggregates was analyzed by gel chromatography. RESULTS: At concentrations from 0.005 to 1 microgram/ml, hydrocortisone was found to produce a similar dose-dependent stimulation of aggrecan synthesis in both matrices. The synthesis of aggrecans remained at the same level for concentrations of 1 microgram/ml up to 100 micrograms/ml of hydrocortisone. When supraphysiological concentrations of hydrocortisone were added the aggrecan synthesis rate plateau declined. Simultaneously with the increase in aggrecan synthesis, the proportion of low-molecular weight 35S-proteoglycans decreased in favour of 35S-aggrecan aggregates and monomers in the agarose system. The chondrocytes cultured in alginate showed this increase of aggrecan aggregates and monomeric aggrecans in both the cell-associated and the inter-territorial matrix. CONCLUSION: Hydrocortisone is a stimulator of aggrecan synthesis by normal human articular chondrocytes cultured in vitro. The two culture systems (agarose and alginate) tested in this experiment showed a comparable aggrecan synthesis rate, increasing under the influence of hydrocortisone at concentrations up to 1 microgram/ml. The proportions of 35Sulphate incorporated in aggrecan aggregates and monomeric aggrecan were also higher under the influence of hydrocortisone.  相似文献   
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