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   718篇
  免费   42篇
  国内免费   7篇
耳鼻咽喉   6篇
儿科学   42篇
妇产科学   13篇
基础医学   95篇
口腔科学   49篇
临床医学   76篇
内科学   156篇
皮肤病学   7篇
神经病学   46篇
特种医学   22篇
外科学   53篇
综合类   20篇
一般理论   6篇
预防医学   50篇
眼科学   14篇
药学   61篇
中国医学   3篇
肿瘤学   48篇
  2024年   2篇
  2023年   31篇
  2022年   47篇
  2021年   64篇
  2020年   43篇
  2019年   40篇
  2018年   54篇
  2017年   36篇
  2016年   20篇
  2015年   24篇
  2014年   39篇
  2013年   41篇
  2012年   64篇
  2011年   52篇
  2010年   22篇
  2009年   20篇
  2008年   42篇
  2007年   25篇
  2006年   17篇
  2005年   17篇
  2004年   17篇
  2003年   12篇
  2002年   14篇
  1999年   2篇
  1998年   1篇
  1996年   2篇
  1995年   1篇
  1992年   2篇
  1991年   1篇
  1990年   1篇
  1989年   1篇
  1987年   1篇
  1986年   1篇
  1985年   1篇
  1984年   2篇
  1983年   1篇
  1982年   2篇
  1975年   1篇
  1974年   1篇
  1972年   1篇
  1967年   1篇
  1964年   1篇
排序方式: 共有767条查询结果,搜索用时 15 毫秒
41.

Background and objectives

Lowering the dialysate temperature may improve outcomes for patients undergoing chronic hemodialysis. We reviewed the reported benefits and harms of lower temperature dialysis.

Design, setting, participants, & measurements

We searched the Cochrane Central Register, OVID MEDLINE, EMBASE, and Pubmed until April 15, 2015. We reviewed the reference lists of relevant reviews, registered trials, and relevant conference proceedings. We included all randomized, controlled trials that evaluated the effect of reduced temperature dialysis versus standard temperature dialysis in adult patients receiving chronic hemodialysis. We followed the Grading of Recommendations Assessment, Development and Evaluation approach to assess confidence in the estimates of effect (i.e., the quality of evidence). We conducted meta-analyses using random effects models.

Results

Twenty-six trials were included, consisting of a total of 484 patients. Compared with standard temperature dialysis, reduced temperature dialysis significantly reduced the rate of intradialytic hypotension by 70% (95% confidence interval, 49% to 89%) and significantly increased intradialytic mean arterial pressure by 12 mmHg (95% confidence interval, 8 to 16 mmHg). Symptoms of discomfort occurred 2.95 (95% confidence interval, 0.88 to 9.82) times more often with reduced temperature compared with standard temperature dialysis. The effect on dialysis adequacy was not significantly different, with a Kt/V mean difference of −0.05 (95% confidence interval, −0.09 to 0.01). Small sample sizes, loss to follow-up, and a lack of appropriate blinding in some trials reduced confidence in the estimates of effect. None of the trials reported long-term outcomes.

Conclusions

In patients receiving chronic hemodialysis, reduced temperature dialysis may reduce the rate of intradialytic hypotension and increase intradialytic mean arterial pressure. High–quality, large, multicenter, randomized trials are needed to determine whether reduced temperature dialysis affects patient mortality and major adverse cardiovascular events.  相似文献   
42.

Background

The authors present a retrospective analysis of 45 patients who underwent treatment of CNS lymphoma (both primary and secondary) at a single institution between 2005 and 2012.

Methods

This study involves 21 female and 24 male patients with a mean age of 59.2 years. All medical records and pathology reports were reviewed for each patient. Univariate and multivariate analyses of overall survival were performed.

Results

Presentation with altered mental status was a significant risk factor for worse overall survival. An HIV infection, deep lesion location, and age over 60 did not impact survival. A survival benefit was demonstrated with the use of systemic therapy, specifically rituximab, and radiation. The CNS Lymphoma Score was derived from this cohort, which proved a powerful predictive tool for overall survival. The surgical complication rate in this series was 17.8 %.

Conclusions

This study highlights the prognostic importance of presenting mental status on outcomes in CNS lymphoma and demonstrates a summative benefit of rituximab and whole brain radiation therapy. Considering these factors together provides an easily applicable and meaningful stratification for this patient population. The surgical complication rate in this patient population is not negligible. The high percentage of wound-related surgical complications suggests the need for a waiting period between surgery and initiation of chemotherapy to allow for wound healing.  相似文献   
43.
Viral respiratory infections (VRIs) contribute to the morbidity and transplant-related mortality (TRM) after allogeneic haematopoietic stem cell transplantation (HSCT) and strategies to prevent and treat VRIs are warranted. We monitored VRIs before and after transplant in children undergoing allogeneic HSCT with nasopharyngeal aspirates (NPA) and assessed the impact on clinical outcome. Between 2007 and 2017, 585 children underwent 620 allogeneic HSCT procedures. Out of 75 patients with a positive NPA screen (12%), transplant was delayed in 25 cases (33%), while 53 children started conditioning with a VRI. Patients undergoing HSCT with a positive NPA screen had a significantly lower overall survival (54% vs. 79%) and increased TRM (26% vs. 7%) compared to patients with a negative NPA. Patients with a positive NPA who delayed transplant and cleared the virus before conditioning had improved overall survival (90%) and lower TRM (5%). Pre-HSCT positive NPA was the only significant risk factor for progression to a lower respiratory tract infection and was a major risk factor for TRM. Transplant delay, whenever feasible, in case of a positive NPA screen for VRIs can positively impact on survival of children undergoing HSCT.  相似文献   
44.

Background

Self-expandable metal stents (SEMS) and self-expandable plastic stents (SEPS) maybe used for the treatment of benign upper gastrointestinal (GI) leaks and strictures. This study reviewed our experience with stent insertions in patients with benign upper GI conditions.

Methods

Patients who underwent stent placement for benign upper GI strictures and leaks between March 2007 and April 2011 at a tertiary referral academic center were studied using an endoscopic database and electronic patient records. The technical success, complications, and clinical improvement after stent removal were compared according to type of stent. The outcomes measured were clinical response, adverse events, and predictors of stent migration.

Results

Thirty-eight patients (50 % male, mean age = 54 years, range = 12–82) underwent 121 endoscopic procedures. Twenty patients had stents placed for strictures, and 18 had stents placed for leaks. Stent placement was technically successful in all patients. The average duration of stent placement was 54 days (range = 18–118). Clinical improvement immediately after stent placement was seen in 29 of the 38 patients (76.3 %). Immediate post-procedure adverse events occurred in 8 patients. Late adverse events were seen in 18 patients. Evidence of stent migration occurred in 16 patients and was seen in 42 of the 118 successfully placed stents (35.5 %). Migration was more frequent with fully covered SEMS (p = 0.002). After stent removal, 27 patients were evaluable for long-term success (median follow-up time of 283 days, IQR 38–762). Resolution of strictures or leaks was seen in 11 patients (40.7 %). Predictors for long-term success included increasing age and if the stent did not cross the GE junction.

Conclusions

Placement of SEPS and SEMS for benign refractory strictures and fistulas has modest long-term clinical efficacy and is limited by a significant migration rate. Stent migration is common and frequent with fully covered SEMS compared to other types of stents, regardless of indication or location.  相似文献   
45.
Cardiovascular disease remains the leading cause of death worldwide with hypertension being a major contributing factor to cardiovascular disease–associated mortality. On a population level, non-pharmacological approaches, such as alternative/complementary medicine, including phytochemicals, have the potential to ameliorate cardiovascular risk factors, including high blood pressure. Several epidemiological studies suggest an antihypertensive effect of garlic (Allium sativum) and of many its bioactive components. The aim of this review is to present an in-depth discussion regarding the molecular, biochemical and cellular rationale underlying the antihypertensive properties of garlic and its bioactive constituents with a primary focus on S-allyl cysteine and allicin. Key studies, largely from PubMed, were selected and screened to develop a comprehensive understanding of the specific role of garlic and its bioactive constituents in the management of hypertension. We also reviewed recent advances focusing on the role of garlic bioactives, S-allyl cysteine and allicin, in modulating various parameters implicated in the pathogenesis of hypertension. These parameters include oxidative stress, nitric oxide bioavailability, hydrogen sulfide production, angiotensin converting enzyme activity, expression of nuclear factor–κB and the proliferation of vascular smooth muscle cells. This review suggests that garlic and garlic derived bioactives have significant medicinal properties with the potential for ameliorating hypertension and associated morbidity; however, further clinical and epidemiological studies are required to determine completely the specific physiological and biochemical mechanisms involved in disease prevention and management.  相似文献   
46.
rATG is used for HTx induction but is costly and associated with infection and PTLD. Hypothesis: Tailoring rATG induction with CD3 monitoring results in less infection, reduced costs, and similar rejection. Retrospective review of HTx recipients receiving rATG induction. Control cases received “usual” rATG dosing (1.5 mg/kg/day typically × 5 days). Starting in October 2009, absolute CD3 monitoring (target <25 cells/mm3) guided rATG dosing (study cases). Outcomes included first‐year incidence of infection/rejection, direct costs of therapy, and incidence of PTLD/death. Study cases (n = 32) received fewer doses of rATG (median 4 vs. 5, p < 0.001) and less total rATG (median 3.2 vs. 7.4 mg/kg, p < 0.001) compared with controls (n = 17). There was no difference in incidence of infection, rejection, or patient survival during the first year post‐HTx. There was one early death in both groups and one late case of PTLD in the control group. Drug savings were significant (median drug cost per patient $2718 vs. $4756, p < 0.001). CD3‐tailored rATG induction in HTx recipients is associated with reduced drug costs and similar rates of rejection/infection. Longer follow‐up will determine whether extended benefits are associated with this induction monitoring strategy.  相似文献   
47.
48.
Hepatocellular carcinoma (HCC) is the sixth most common primary malignancy worldwide, and the third most common cause of death among cancers worldwide. HCC occurs in several pre-existing conditions, including hepatitis C, hepatitis B virus, and non-alcoholic cirrhosis. Egypt used to be the country with the heaviest hepatitis C virus (HCV) burden. The relationship between HCV and HCC is an important research area. In Egypt, HCC is a significant public health problem. A possible cause for the increasing rates of detection of HCC in Egypt is the mass screening program that was carried by the government for detecting and treating HCV. A multidisciplinary approach is now widely applied to HCC management in health centers all over Egypt. Different treatment modalities are available in Egypt, with success rates comparable to global rates. The Egyptian health authorities have made the elimination of HCV from Egypt a special priority, and this approach should lead to a decrease in number of HCC cases in the near future. In this article we review the current situation of HCC in Egypt, including epidemiological aspects, relevant risk factors for HCC development, strategies, and efforts established by health authorities for the screening and prevention of both HCV and HCC in Egypt. We highlight the different modalities for HCC treatment.  相似文献   
49.
There has been an increasing number of reported cases of acute hepatitis of unknown origin in previously healthy children since first reported on March 31,2022.This clinical syndrome is identified by jaundice and markedly elevated liver enzymes with increased aspartate transaminase and/or alanine amino transaminase(greater than 500 IU/L).We conducted an inclusive literature review with respect to acute hepatitis outbreaks in children using the search terms acute hepatitis,outbreak,children,sever...  相似文献   
50.
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