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   671篇
  免费   43篇
  国内免费   15篇
耳鼻咽喉   4篇
儿科学   62篇
妇产科学   3篇
基础医学   70篇
口腔科学   12篇
临床医学   65篇
内科学   129篇
皮肤病学   16篇
神经病学   16篇
特种医学   117篇
外科学   36篇
综合类   106篇
预防医学   50篇
眼科学   3篇
药学   18篇
中国医学   1篇
肿瘤学   21篇
  2023年   2篇
  2022年   3篇
  2021年   8篇
  2020年   3篇
  2019年   5篇
  2018年   4篇
  2017年   8篇
  2016年   9篇
  2015年   17篇
  2014年   23篇
  2013年   17篇
  2012年   28篇
  2011年   15篇
  2010年   35篇
  2009年   36篇
  2008年   33篇
  2007年   27篇
  2006年   18篇
  2005年   13篇
  2004年   9篇
  2003年   13篇
  2002年   12篇
  2001年   21篇
  2000年   9篇
  1999年   19篇
  1998年   46篇
  1997年   40篇
  1996年   31篇
  1995年   19篇
  1994年   27篇
  1993年   22篇
  1992年   7篇
  1991年   10篇
  1990年   6篇
  1989年   14篇
  1988年   12篇
  1987年   25篇
  1986年   9篇
  1985年   12篇
  1984年   4篇
  1983年   7篇
  1982年   14篇
  1981年   5篇
  1980年   5篇
  1979年   1篇
  1978年   8篇
  1977年   4篇
  1976年   8篇
  1975年   5篇
  1967年   1篇
排序方式: 共有729条查询结果,搜索用时 15 毫秒
41.
42.
Michael  AS; Mafee  MF; Valvassori  GE; Tan  WS 《Radiology》1985,154(2):413-419
A retrospective review of the dynamic CT studies performed in our institution on head and neck lesions, excluding the brain, was carried out. Five basic types of density vs. time curves were obtained. Dynamic CT scanning is valuable in the differential diagnosis, management, and followup of such cases; its usefulness as an imaging modality in diagnosis and followup of hemangiomas is stressed.  相似文献   
43.
In order to confirm the phenomenon of tracking of cardiovascular risk factors among school children, we undertook in 2003, a prospective survey of a population of 789 pupils aged 13 to 15 years who had participated in a first investigation on cardiovascular risk factors in 1999. We were able to follow and study 453 pupils (57.4% of the initial population). Prevalences of hypertension and obesity were respectively 11.3% and 6.1% without significant difference between sexes. On the other hand, hypercholesterolemia was significantly more elevated among girls than boys (16.1% versus 9.3%, p = 0.039). Children classified initially as hypertensive, obese or having a hypercholesterolemia were identified 4 years later at a subsequent exam as hypertensive, obese or having a hypercholesterolemia in respectively 25%, 48.9% and 59%. The stability of cardiovascular risk factors among children imposes an early screening for a better management and a policy of cardiovascular health promotion since childhood based essentially on prevention of risk factors in order to reduce the cardiovascular disease burden in adulthood.  相似文献   
44.
45.

Background

Pre dose or trough blood cyclosporine (CSA) concentration is routinely monitored and the result is used to alter patient''s drug dosing. Patients with identical pre dose blood CSA may have very different systemic exposure to the drug. Recently CSA 2 hour post dose level [C2] has been reported to correlate better with drug exposure. We undertook this study to evaluate the influence of trough and C2, CSA concentration monitoring on short-term renal allograft outcomes.

Methods

25 patients of renal transplant receiving a triple drug regimen of CSA micro emulsion (Panacea Biotec) 8mg/kg, azathioprine 1mg/kg and prednisolone 0.5mg/kg were analyzed prospectively for graft outcomes. CSA levels were monitored in whole blood by radioimmunoassay using monoclonal antibodies, at 72 hours after the transplant.

Results

The mean age of patients was 37.08 + 9.1 years. There were 20 males and 5 females. The mean age of donors was 40.2 + 8.2 years. There were 11 related donors with at least a haplomatch, 4 spousal and 10 unrelated donors with a nil antigen match. The mean pre dose CSA concentration was 289.22 + 171.9ng/ml; range (98.8 + 783.41ng/ml). The CSA concentration at 2 hours after the CSA administration was 838 + 310.87ng/ml (range, 169 + 1268ng/ml). 3 (12%) patients had acute rejection. In these patients the mean pre dose CSA concentration was 328.67ng/ml and the mean C2, CSA concentration was 1006.26ng/ml. CSA induced hemolytic uraemic syndrome was diagnosed in one patient. The trough and C2, CSA concentration levels were 174 and 870.83ng/ml respectively in this patient.

Conclusion

In our study CSA levels, trough and peak showed significant inter patient variability. The trough and C2 concentration levels did not correlate with the episodes of acute rejection. We conclude that in a triple drug regimen with fixed dosing schedules routine trough CSA level monitoring is not helpful in the acute post renal transplant period.Key Words: Cyclosporine levels, Cyclosporine trough levels, C2 levels  相似文献   
46.
Background Stress echocardiography is useful for assessing patients with coronary artery disease unable to undergo formal exercise testing. Considerable skill is required to avoid large intra- and inter-observer variability due to poor endocardial definition. Intravenous ultrasound contrast agents are now available which may improve this variability. Aim To study intravenous Sonovue in assessing wall motion score and ejection fraction (EF) during stress echocardiography. Methods Thirty-eight patients undergoing arbutamine stress echocardiography for known or suspected coronary artery disease were studied. Echocardiographic analysis of wall motion score index, endocardial border detection (EBD) and EF was performed at rest and at peak stress before and after intravenous injection of Sonovue, by experienced and inexperienced observers. Results All three observers noted an improvement in endocardial border definition following Sonovue (p=<0.001). At baseline, there was a significant difference in wall motion score index between experienced and inexperienced observers at rest (p=0.01) and at peak stress (p=0.001). Following Sonovue administration this was no longer significant (p=0.07, p=0.114). Intra-observer variability of end diastolic, end systolic volumes (ESV) and EF improved following contrast (p<0.05) at rest and during stress. Conclusion Sonovue significantly improved EBD and reduced intra-observer variability of EF at rest and during peak arbutamine infusion.  相似文献   
47.
A child showing signs of Henoch-Sch?nlein purpura developed a right tibiofibular vascular thrombosis. Antiphospholipid antibody tests were positive for both lupus anticoagulant and anticardiolipin antibodies. This suggests that an antiphospholipid syndrome should be considered in cases of Henoch-Sch?nlein purpura and antiphospholipid antibodies should be measured to determine whether prophylactic antithrombotic measures are needed to prevent thrombotic manifestations.  相似文献   
48.
Informed Consent     
There have been significant changes in the doctor patient relationship with the impact of technology in day-to-day practice. More and more patients are aware of their rights and are keen to make free choice and decision on their treatment. This helps them to choose the treatment of their choice from the options available and to select a physician of their choice. Doctor's decisions are being questioned regarding their correctness and there is a need to educate the patient, on what one offers by way of treatment. In some procedures and types of treatment, patient needs to be educated and informed of the merits and demerits of the treatment available. This will help the patient to make appropriate choice and also to accept some adverse outcome of treatment. Towards this end, all countries are looking afresh at the necessity of Informed Consent. Methods adopted by some countries are highlighted to help our physicians practice them in an appropriate way. A lot of remedial work needs to be done to minimize future litigation, as many doctors misunderstand their legal obligations and haven't caught up with the change in judge's thinking.  相似文献   
49.
The beta2 integrin (CD 18/CD 11 a, b, c) family of proteins mediate adherence of leukocytes to vascular endothelium and the associated ligand, intercellular adhesion molecule-1 (ICAM-1; CD 54), interacts with beta2 integrin proteins to allow transendothelial migration of leukocytes into sites of inflammation. The present study examines the function of these proteins in a murine model of acute cutaneous inflammation induced following topical application of 12-O- tetradecanoylphorbol-13-acetate (TPA) to the dorsal epidermis of SENCAR mice and in a model of skin multistage carcinogenesis. At 24 h following topical application of TPA to the dorsal epidermis of mice, dermal leukocytes expressed higher levels of beta2 integrin protein compared with the lower levels of beta2 integrin protein expression by peripheral blood leukocytes. ICAM-1 protein was localized to epidermal keratinocytes and vascular endothelium in TPA-treated skin and to proliferating papilloma cells. Intravenous (i.v.) injection of either 50 microg anti-beta2 integrin antibody alone or in combination with anti-ICAM-1 antibody significantly inhibited both TPA-stimulated neutrophil infiltration into the dermis (P < 0.001) and myeloperoxidase (MPO) activity (P < 0.03 anti-beta2 integrin antibody; P < 0.01 anti- beta2 integrin + ICAM-1 adhesion molecule antibodies), but had no effect on TPA-induced epidermal hyperplasia. In addition, injection of either anti-ICAM-1 adhesion molecule antibody alone (P < 0.004) or in combination with anti-beta2 integrin antibody (P < 0.001) significantly inhibited TPA-induced production of 7,8-dihydroxy-2'-deoxyguanosine (8- OHdG) immunoreactive proteins by epidermal keratinocytes. Beta2 integrin/ICAM-1 adhesion molecules work in concert to regulate migration, retention and functional activation of leukocytes within the dermis during TPA-induced skin inflammation and within stromal tissue of papillomas that form during multi-stage carcinogenesis. Agents that inhibit these receptor/ligand interactions may be useful in defining the roles of specific cell populations in cutaneous inflammation and multistage carcinogenesis and may also have potential as anti-promoting and anti-progression agents.   相似文献   
50.
OBJECTIVES: The aim of our study is to evaluate anatomic regeneration and metabolic derangement of the liver after major resection in dogs. METHODS: This is an experimental study on 9 dogs; we divided the dogs in two groups: the first group (5 dogs) underwent at one go major hepatectomy (90% of the liver).The second group (4 dogs) underwent successively a resection of 75% of the liver and a second resection of 90% of the restored liver six months later. All dogs underwent a metabolic and morphologic studies of the liver and of their kidney function. RESULTS: In the first group; all dogs which underwent 90% hepatic resection died 48 hours after the surgical resection of hepatic insufficiency. The ultra microscopic study showed the role of portal hypertension in hepatic degeneration on the first group. In the second group, the dogs survived the first resection, and our study shows a regeneration of the liver after resection and sub normal hepatic function. CONCLUSION: The liver is able to regenerate after minimally resection but major resection must be done by successively resection to avoid hepatic dysfunction, but the time between resection must be evaluate later.  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