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   566篇
  免费   26篇
  国内免费   2篇
耳鼻咽喉   2篇
儿科学   56篇
妇产科学   3篇
基础医学   74篇
口腔科学   11篇
临床医学   73篇
内科学   136篇
皮肤病学   21篇
神经病学   2篇
特种医学   140篇
外科学   26篇
综合类   11篇
预防医学   6篇
眼科学   4篇
药学   13篇
肿瘤学   16篇
  2022年   2篇
  2021年   5篇
  2019年   2篇
  2018年   6篇
  2016年   5篇
  2015年   9篇
  2014年   9篇
  2013年   16篇
  2012年   6篇
  2011年   10篇
  2010年   23篇
  2009年   21篇
  2008年   8篇
  2007年   6篇
  2006年   12篇
  2005年   7篇
  2004年   5篇
  2003年   9篇
  2002年   4篇
  2001年   4篇
  2000年   2篇
  1999年   3篇
  1998年   35篇
  1997年   46篇
  1996年   45篇
  1995年   38篇
  1994年   19篇
  1993年   22篇
  1992年   8篇
  1991年   13篇
  1990年   6篇
  1989年   17篇
  1988年   27篇
  1987年   21篇
  1986年   24篇
  1985年   13篇
  1984年   5篇
  1983年   6篇
  1982年   5篇
  1981年   14篇
  1980年   6篇
  1979年   5篇
  1978年   8篇
  1977年   9篇
  1976年   5篇
  1975年   9篇
  1944年   3篇
  1930年   1篇
  1929年   1篇
  1925年   3篇
排序方式: 共有594条查询结果,搜索用时 21 毫秒
21.
22.

INTRODUCTION:

Alterations from first-party and surrogate decision-maker consent can enhance the feasibility of research involving critically ill patients.

OBJECTIVE:

To describe the use of a deferred-consent model to enable participation of critically ill patients in a minimal-risk biomarker study.

METHODS:

A prospective observational study was conducted in which serum biomarker samples were collected three times daily over the first 14 days following aneurysmal subarachnoid hemorrhage. Sample collection was initiated on intensive care unit admission and consent was obtained when research personnel could approach the patient or the patient’s surrogate decision maker.

RESULTS:

Twenty-seven patients were eligible for the study, of whom only five were capable of providing informed consent. Full consent was obtained for 21 (78%) patients through self- (n=4) and surrogate (n=17) consent. Partial consent or refusal (only permitting the collection of blood samples as a part of routine care or use of data) occurred in three patients. Among the 22 consents sought from surrogates, three (11%) refused participation. The refusals included the sickest patients in the cohort. Once consent was provided, no patient or surrogate withdrew consent before study completion.

DISCUSSION:

Use of a deferred consent model enabled participation of critically ill patients in a minimal-risk biomarker study with no withdrawals.

CONCLUSIONS:

Further research and enhanced awareness of the potential utility of hybrid models, including deferred consent in addition to patient or surrogate consent, in the conduct of low-risk and minimally interventional time-sensitive studies of critically ill patients are required.  相似文献   
23.
24.
BackgroundThere is some evidence to support the use of suprascapular nerve blocks (SSNBs) to manage shoulder pain. Although many patients with shoulder pain are referred to physiotherapy, there are no data describing whether physiotherapists currently use SSNBs for these patients.ObjectiveTo explore if physiotherapists who manage musculoskeletal shoulder pain are using SSNBs and identify, of those who responded to an online questionnaire, how commonplace this practice is in the United Kingdom (UK)DesignAn online, cross-sectional, questionnaire survey was developed for physiotherapists involved in the management of patients with shoulder pain.MethodsA snowball sampling method was used to invite physiotherapists to complete the online survey, using email, research advertisements in a professional magazine and via social media. The questionnaire captured respondents’ demographic and professional practice characteristics, their knowledge and use of SSNBs and their views and experiences regarding SSNBs as a treatment for shoulder pain.ResultsIn total, there were 529 responders to the survey. Of these, 492 were eligible and formed the sample for analyses. The majority of responders (290/474; 61%) were from the UK. Of these, the majority (259/282; 92%) were familiar with SSNBs as a method of treatment for shoulder pain, although few (9/149; 6%) reported regularly using SSNBs in their clinical practice. Only 8 of 287 responders from the UK (3%) reported delivering SSNBs to patients.ConclusionsThis survey provides preliminary evidence that the use and delivery of SSNBs by UK physiotherapists is uncommon. Future research is required to investigate the potential value of physiotherapists using this treatment option for their patients with shoulder pain.  相似文献   
25.
Endotoxin is a component of gram-negative bacteria that causes hematologic and immunologic changes through its induction of cytokines. Interleukin-1 receptor antagonist (IL-1Ra) is a naturally occurring inhibitor of IL-1 that competes with IL-1 for occupancy of cell-surface receptors but possesses no agonist activity. We investigated the ability of human recombinant IL-1Ra to block the effects of low-dose endotoxin. Fourteen healthy male volunteers between 18 and 30 years old were injected intravenously with 3 ng/kg Escherichia coli endotoxin. Concurrent with the injections, nine volunteers received a 3-hour continuous intravenous infusion of IL-1Ra. The other five subjects were given a 3-hour infusion of saline. Volunteers injected with endotoxin experienced a threefold increase in circulating neutrophils over baseline. This neutrophilia was significantly reduced by 48% in subjects administered endotoxin plus IL-1Ra (P = .0253). Ex vivo mitogen-induced peripheral blood mononuclear cell proliferation decreased by greater than 60% at 3 and 6 hours after endotoxin injection (P = .0053). This endotoxin-induced reduction in mitogen response was reversed in subjects coinjected with IL-1Ra (P = .0253). Endotoxin-induced symptoms, fever, and tachycardia were unaffected by IL-1Ra. IL-1 appears to be an important mediator in endotoxemia because some of its hematologic and immunomodulatory effects can be blocked by IL-1Ra.  相似文献   
26.
Noorman  F; Braat  EA; Rijken  DC 《Blood》1995,86(9):3421-3427
The balance of tissue-type plasminogen activator (t-PA) production and degradation determines its concentration in blood and tissues. Disturbance of this balance may result in either increased or decreased proteolysis. In the present study, we identified the receptor systems involved in the degradation of t-PA by human monocytes/macrophages in culture. Monocytes were cultured and became macrophages within 2 days. At 4 degrees C, 125I-t-PA bound to macrophages with high (apparent dissociation constant [kd], 1 to 5 nmol/L) and low affinity (kd > 350 nmol/L). At 37 degrees C, the cells internalized and degraded t-PA via the high affinity binding sites, which were partially inhibited by mannan. The low affinity binding sites were 6-aminohexanoic acid- inhibitable and not involved in t-PA degradation. Degradation of t-PA was upregulated during differentiation of monocytes to macrophages. Dexamethasone further upregulated the mannan-inhibitable t-PA degradation. Lipopolysaccharide downregulated both mannan-inhibitable and non-mannan-inhibitable t-PA degradation. Non-mannan-inhibitable degradation was completely blocked by recombinant 39-kD receptor- associated protein (RAP, inhibitor of lipoprotein receptor-related protein [LRP]), whereas mannan-inhibitable degradation was blocked by the addition of a monoclonal antibody against the mannose receptor. No differences between the degradation of t-PA and functionally inactivated t-PA were observed. We conclude that human monocyte-derived macrophages are able to bind, internalize, and degrade t-PA. Degradation of t-PA does not require complex formation with plasminogen activator inhibitors. The macrophages use two independently regulated receptors, namely, the mannose receptor and LRP, for the uptake and degradation of t-PA.  相似文献   
27.
Systemic non‐biologic agents have long been in clinical use in medicine – often with considerable efficacy, albeit with some adverse effects – as with all medications. With the advent of biologic agents, all of which currently are restricted to systemic use, there is a growing need to ensure which agents have the better therapeutic ratio. The non‐biologic agents (NBAs) include a range of agents, most especially the corticosteroids (corticosteroids). This study reviews the corticosteroids in systemic use in management of orofacial mucocutaneous diseases; subsequent studies discuss corticosteroid‐sparing agents used in the management of orofacial diseases, such as calcineurin inhibitors used to produce immunosuppression; purine synthetase inhibitors; and cytotoxic and other immunomodulatory agents.  相似文献   
28.
29.
The determinants of the degree of metabolic decompensation at the diagnosis of type 1 (insulin dependent) diabetes mellitus (IDDM) and the possible role of diabetic ketoacidosis in the preservation and recovery of residual beta cell function were examined in 745 Finnish children and adolescents. Children younger than 2 years or older than 10 years of age were found to be more susceptible to diabetic ketoacidosis than children between 2 and 10 years of age (< 2 years: 53.3%; 2-10 years: 16.9%; > 10 years: 33.3%). Children from families with poor parental educational level had ketoacidosis more often than those from families with high parental educational level (24.4% v 16.9%). A serum C peptide concentration of 0.10 nmol/l or more was associated with a favourable metabolic situation. Low serum C peptide concentrations, high requirement of exogenous insulin, low prevalence of remission, and high glycated haemoglobin concentrations were observed during the follow up in the group of probands having diabetic ketoacidosis at the diagnosis of IDDM. Thus diabetic ketoacidosis at diagnosis is related to a decreased capacity for beta cell recovery after the clinical manifestation of IDDM in children.  相似文献   
30.
Bacterial endocarditis is an uncommon diagnosis in childhood with significant morbidity and mortality. Aortic aneurysm as a complication is well described in adults but there are few reports in the paediatric literature. Two children with bacterial endocarditis are described, whose illnesses were complicated by aortic aneurysm formation requiring surgical intervention.  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