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   709篇
  免费   47篇
  国内免费   17篇
耳鼻咽喉   2篇
儿科学   43篇
妇产科学   7篇
基础医学   57篇
口腔科学   11篇
临床医学   72篇
内科学   152篇
皮肤病学   13篇
神经病学   25篇
特种医学   230篇
外科学   52篇
综合类   33篇
预防医学   28篇
眼科学   4篇
药学   16篇
中国医学   4篇
肿瘤学   24篇
  2023年   1篇
  2022年   4篇
  2021年   12篇
  2020年   11篇
  2019年   5篇
  2018年   9篇
  2017年   7篇
  2016年   14篇
  2015年   10篇
  2014年   11篇
  2013年   21篇
  2012年   16篇
  2011年   15篇
  2010年   21篇
  2009年   27篇
  2008年   14篇
  2007年   23篇
  2006年   15篇
  2005年   16篇
  2004年   7篇
  2003年   17篇
  2002年   9篇
  2001年   3篇
  2000年   4篇
  1999年   12篇
  1998年   46篇
  1997年   48篇
  1996年   38篇
  1995年   22篇
  1994年   40篇
  1993年   25篇
  1992年   6篇
  1991年   12篇
  1990年   9篇
  1989年   28篇
  1988年   20篇
  1987年   18篇
  1986年   26篇
  1985年   14篇
  1984年   16篇
  1983年   12篇
  1982年   13篇
  1981年   24篇
  1980年   6篇
  1979年   5篇
  1978年   9篇
  1977年   11篇
  1976年   11篇
  1975年   10篇
排序方式: 共有773条查询结果,搜索用时 15 毫秒
71.
72.
73.
A 3 year old Turkish girl is described who was suffering from major histocompatibility complex (MHC) class II deficiency syndrome, which is characterised by the lack of expression of HLA class II antigens on mononuclear cells. The presence of HLA class II genes was demonstrable at the DNA level. Combined immunodeficiency was indicated by hypogammaglobulinaemia and the absence of delayed type hypersensitivity on skin testing. Further, she was unable to produce specific antibodies towards foreign antigens and suffered from recurrent pulmonary, gastrointestinal, and septic infections from the third month of life. The clinical course was complicated by a Coombs test positive haemolytic anaemia due to the production of autoantibodies against the rhesus "e' antigen, a non-glycosylated protein antigen. Haemolysis could be controlled by oral steroid treatment. This case is of interest as it shows that despite the absence of HLA class II antigens and combined immunodeficiency autoimmune reactions with production of specific autoantibodies directed to protein antigens are possible.  相似文献   
74.

Background  

In the Philippines, traditional mass dog vaccination campaigns have only achieved limited and transient success in dog rabies control, mainly because a large segment of the dog population is not accessible for traditional parenteral vaccination. Oral vaccination of dogs has been suggested as a supplementary method to increase the overall vaccination coverage of the dog populations involved. For this purpose, it is necessary to identify a suitable bait that is readily accepted by local dogs and that can be prepared without high costs.  相似文献   
75.
Immunoglobulin (Ig) was demonstrated in paraffin sections of 12 trephine bone marrow biopsies by means of the unlabelled antibody peroxidase-antiperoxidase (PAP) method. The Ig-containing cells, which were counted with the Reichert-Jung (Kontron) MOP-AMO3 user-controlled image-analyser, were found to constitute approximately 4·2% of all the nucleated cells in the marrow, a figure significantly higher than those reported by previous workers.  相似文献   
76.
In this study, the psychological functioning of patients with chronic post-traumatic headache (PTH), chronic combination headache and chronic low back pain without headache, whose time of onset was similar, and a matched group of controls was investigated. The Symptom Checklist 90-Revised (SCL-90-R), State-Trait Anger Expression Inventory (STAXI), State-Trait Anxiety Inventory, Form Y (STAI-Y), and Beck Depression Inventory (BDI) were used to assess the degree of psychopathology. A MANOVA test indicated highly significant differences between groups. In general, the pain groups fell along a continuum with PTH subjects demonstrating the highest elevations, back pain subjects demonstrating the next highest elevations, and combination subjects demonstrating fewer elevations. A cluster analysis indicated that findings were best classified into four clusters, but no one pain diagnosis predominated in any cluster. Eighty-nine percent of controls were assigned to clusters 1 or 2, which revealed essentially normal scores on all tests. It is suggested that while chronic pain patients demonstrate more psychopathology than non-pain controls, a variety of coping styles exists within each pain group independent of diagnostic categorization.  相似文献   
77.
囊性纤维化相关性糖尿病(CFRD)是囊性纤维化(CF)的并发症,主要由胰岛素分泌不足引起,在青少年和成人中的发病率分别为20%和40%~50%。本指南由美国糖尿病协会(ADA)、囊性纤维瘤基金会(CFF)和儿童内分泌学会共同发布,包括CFRD的筛查、诊断和治疗。  相似文献   
78.
Patients aged ≥80 years are at high risk of adverse events after coronary artery bypass grafting. This study was performed to evaluate whether off-pump coronary artery bypass surgery (OPCAB) is superior to conventional surgery (CCAB) in these high-risk patients. The outcome of 185 patients aged ≥80 years who underwent OPCAB or CCAB at our institution was reviewed and a meta-analysis on this issue was performed. Similar immediate postoperative results were observed after OPCAB and CCAB at our institution, despite significantly different operative risk (mean logistic EuroSCORE, OPCAB 20.3% vs CCAB 13.4%, P = 0.003). Among 56 propensity score matched pairs a trend toward lower postoperative stroke (0%, 95% CI 0–0 vs 3.6%, 95% CI 0–10.0, P = 0.50) was observed after OPCAB. No significant differences were observed in the other outcome end points. Five-year survival was 81.0% after OPCAB and 78.1% after CCAB (P = 0.239). Pooled analysis of eight studies including 3416 patients showed a significantly higher risk of postoperative stroke after CCAB (pooled rates: 4.2%, 95% confidence interval (95% CI) 2.4–7.1 vs 1.5%, 95% CI 0.9–2.5, risk ratio (RR) 2.15, 95% CI 1.17–3.96, P = 0.01). A trend toward higher immediate postoperative mortality was observed after CCAB (15 studies including 4409 patients, pooled rates: 6.5%, 95% CI 5.2–8.0 vs 5.6%, 95% CI 4.2–7.4, RR 1.29, 95% CI 0.86–1.93, P = 0.21). Generic inverse variance analysis showed similar intermediate survival after CCAB and OPCAB (RR 1.31, 95% CI 0.85–2.01, P = 0.22). At 2 years, survival was 82.8% (95% CI 76.4–89.2) after CCAB and 88.3% (95% CI 82.9–93.7) after OPCAB. Current results indicate that OPCAB compared with CCAB in patients aged ≥80 years is associated with significantly lower postoperative stroke and with a trend toward better early survival. However, suboptimal quality of the available studies, particularly the lack of comparability of the study groups, prevents conclusive results on this controversial issue.  相似文献   
79.
囊性纤维化相关性糖尿病(CFRD)是囊性纤维化(CF)的并发症,主要由胰岛素分泌不足引起,在青少年和成人中的发病率分别为20%和40%~50%。本指南由美国糖尿病协会(ADA)、囊性纤维瘤基金会(CFF)和儿童内分泌学会共同发布,包括CFRD的筛查、诊断和治疗。  相似文献   
80.
We report here on a preliminary human autologous transplantation study of retroviral gene transfer to bone marrow (BM) and peripheral blood (PB)-derived CD34-enriched cells. Eleven patients with multiple myeloma or breast cancer had cyclophosphamide and filgrastim-mobilized PB cells CD34-enriched and transduced with a retroviral marking vector containing the neomycin resistance gene, and CD34-enriched BM cells transduced with a second marking vector also containing a neomycin resistance gene. After high-dose conditioning therapy, both transduced cell populations were reinfused and patients were followed over time for the presence of the marker gene and any adverse effects related to the gene-transfer procedure. All 10 evaluable patients had the marker gene detected at the time of engraftment, and 3 of 9 patients had persistence of the marker gene for greater than 18 months posttransplantation. The marker gene was detected in multiple lineages, including granulocytes, T cells, and B cells. The source of the marking was both the transduced PB graft and the BM graft, with a suggestion of better long-term marking originating from the PB graft. The steady- state levels of marking were low, with only 1:1000 to 1:10,000 cells positive. There was no toxicity noted, and patients did not develop detectable replication-competent helper virus at any time posttransplantation. These results suggest that mobilized PB cells may be preferable to BM for gene therapy applications and that progeny of mobilized peripheral blood cells can contribute long-term to engraftment of multiple lineages.  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