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   1110篇
  免费   161篇
  国内免费   10篇
耳鼻咽喉   15篇
儿科学   103篇
妇产科学   14篇
基础医学   100篇
口腔科学   57篇
临床医学   159篇
内科学   282篇
皮肤病学   12篇
神经病学   54篇
特种医学   165篇
外科学   139篇
综合类   39篇
预防医学   49篇
眼科学   5篇
药学   28篇
中国医学   5篇
肿瘤学   55篇
  2023年   5篇
  2021年   17篇
  2020年   7篇
  2019年   13篇
  2018年   36篇
  2017年   42篇
  2016年   42篇
  2015年   37篇
  2014年   42篇
  2013年   69篇
  2012年   37篇
  2011年   30篇
  2010年   64篇
  2009年   59篇
  2008年   32篇
  2007年   31篇
  2006年   21篇
  2005年   22篇
  2004年   15篇
  2003年   14篇
  2002年   10篇
  2001年   20篇
  2000年   12篇
  1999年   9篇
  1998年   62篇
  1997年   53篇
  1996年   55篇
  1995年   49篇
  1994年   29篇
  1993年   42篇
  1992年   22篇
  1991年   22篇
  1990年   24篇
  1989年   25篇
  1988年   27篇
  1987年   27篇
  1986年   18篇
  1985年   14篇
  1984年   14篇
  1983年   20篇
  1982年   4篇
  1981年   20篇
  1980年   12篇
  1979年   5篇
  1978年   5篇
  1977年   11篇
  1976年   13篇
  1975年   4篇
  1971年   3篇
  1970年   3篇
排序方式: 共有1281条查询结果,搜索用时 15 毫秒
41.
42.

Background

The increased reports of ESBL dissemination from various centres in south western, Nigeria and the recent emergence of carbapenem resistant bacteria prompted the conception of this study.

Objectives

To demonstrate the relationship between high molecular weight plasmids and the expression of antibiotic multi-resistance including ESBL and carbapenemase.

Methods

We investigated 97 isolates of selected organisms consisting of 67 E. coli and 30 Klebseilla spp for the presence of plasmids expressing ESBL including carbapenem-hydrolysing enzymes. Beta-lactamase was determined using acidometric method, while ESBL and carbapenemase activity was determined using the double-disk diffusion test as well as the Modified Hodge test (MHT). Plasmid profiles of ESBL and carbapenemase positive isolates were determined according to standard protocols.

Results

An ESBL prevalence rate of 21.6% and carbapenem- resistance rate of 9.3% was recorded. Antibiotic susceptibility profile of ESBL isolates showed 100.0% resistance against Amoxicillin, Cotrimoxazole and Erythromycin. Moderate susceptibility was recorded against the Quinolone class of antibiotics; Meropenem remained the most active antibiotic against ESBL isolates with 62.5% against E. coli and 60% against K. pneumoniae. The plasmid profiles of our study isolates ranged from 11.8kbp to 35.5kbp.

Conclusion

Due to the relationship between high molecular weight plasmids and multi-drug resistance, we hereby recommend regular molecular surveillance of this form in our study setting.  相似文献   
43.
44.
45.
非酒精性脂肪性肝炎(non—alcoholicsteatohepatitis,NASH)现已成为肝移植愈来愈重要的基础肝病。鉴于晚期NASH患者常并存多种影响肝移植转归的临床问题,而至今尚无针对NASH患者进行肝移植的评估和治疗指南,为此英国移植学会(British Transplant Society,BTS)邀请相关专家制定了指南,以指导肝移植前后NASH患者的处理。  相似文献   
46.

Background

Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemoperfusion (HIPEC) are frequently used to treat appendiceal carcinomatosis. Some patients require multivisceral resection because of the volume of disease. It is unclear whether extent of CRS impacts survival in appendiceal carcinomatosis.

Methods

We analyzed 282 patients undergoing attempted CRS/HIPEC for appendiceal carcinomatosis. Patients were defined as having undergone Extensive CRS (n = 60) if they had >3 organ resections or >2 anastomoses; a subgroup of Extreme CRS patients (n = 10) had ≥5 organ resections and ≥3 anastomoses. Kaplan–Meier survival curves and multivariate Cox-regression models were used to identify prognostic factors affecting outcomes.

Results

Relative to the comparison group, patients undergoing Extensive CRS had a higher median peritoneal carcinomatosis index, operative duration, blood loss, and length of stay. No difference in completeness of cytoreduction, severe morbidity, or 60-day mortality was evident. Subgroup analysis of 10 patients undergoing extreme CRS likewise revealed no increase in severe morbidity or mortality. Median progression-free (PFS) and overall survival (OS) were 23.5 and 74 months in the comparison group; 18.5 (p = 0.086) and 51 (p = 0.85) months in the Extensive CRS group; and 40 months and not reached in the Extreme CRS subgroup. In a multivariable analysis, extent of CRS was not independently associated with PFS or OS.

Conclusions

Extensive CRS is associated with greater OR time, blood loss, and length of stay, but is not associated with higher morbidity, mortality, or inferior oncologic outcomes in patients with appendiceal carcinomatosis.  相似文献   
47.
Background/Objective: Intrathecal baclofen (ITB) has been shown to be an effective treatment for severe spasticity of spinal or cerebral origin. Although most patients respond well to an ITB trial, there are often difficulties in achieving and/or maintaining such effectiveness with ITB pump treatment. There are few published guidelines for dosing efficacy and no studies looking at the effect of concentration of ITB on spasticity management.

Methods: Case series of 3 adults with severe spasticity treated with ITB pump: a 44-year-old man with C7 tetraplegia using a 40-mL Medtronic SynchroMed II pump with 500-μg/mL concentration; a 35-year-old woman with traumatic brain injury with right spastic hemiplegia using a 18-mL Medtronic SynchroMed EL pump with 2,000-μg/mL concentration; and a 43-year-old woman with spastic diplegic cerebral palsy using a 40-mL Medtronic SynchroMed II pump with 2,000-μg/mL concentration.

Results: After reducing ITB concentrations in the pump, either as part of a standard protocol for dye study to assess the integrity of pump and catheter system or secondary to plateau in therapeutic efficacy, patients experienced temporary, significant reduction in spasticity based on range of motion, Modified Ashworth scores, and verbal feedback.

Conclusions: Decreasing the concentration of ITB seems to affect spasticity control. Further research in this area is needed for those patients with refractory spasticity to optimize efficacy of ITB therapy.  相似文献   
48.

Objectives

Although individuals with posttraumatic stress disorder (PTSD) are at heightened risk for several serious health conditions, research has not examined how having PTSD impacts receipt of invasive procedures that may alleviate these problems. We examined whether PTSD, after controlling for major depression, was associated with odds of receiving common types of major invasive procedures, and whether race, ethnicity, and gender was associated with odds of procedures.

Methods

Veterans Health Administration patients with PTSD and/or depression were age-matched with patients without these disorders. The odds of invasive hip/knee, digestive system, coronary artery bypass graft/percutaneous coronary intervention (CABG/PCI), and vascular procedures during FY2006–2009 were modeled for the full sample of 501,489 patients and for at-risk subsamples with medical conditions alleviated by the procedures examined.

Results

Adjusting for demographic covariates and medical comorbidity, PTSD without depression was associated with decreased odds of all types of procedures (odds ratios [OR] range 0.74–0.82), as was depression without PTSD (OR range 0.59–0.77). In analyses of at-risk patients, those with PTSD only were less likely to undergo hip/knee (OR = 0.78) and vascular procedures (OR = 0.73) but not CABG/PCI. African-Americans and women at-risk patients were less likely to undergo hip/knee, vascular, and CABG/PCI procedures (OR range 0.31–0.82).

Conclusion

With the exception of CABG/PCI among at-risk patients, Veterans with PTSD and/or depression were less likely to undergo all types of procedures examined. Future studies should examine the reasons for this disparity and whether it is associated with subsequent adverse outcomes.  相似文献   
49.
50.

Introduction

The median survival of patients with glioblastoma multiforme (astrocytoma grade 4) remains less than 18 months despite radical surgery, radiotherapy and systemic chemotherapy. Surgical implantation of chemotherapy eluting wafers into the resection cavity has been shown to improve length of survival but the current licensed therapy has several drawbacks. This paper investigates in vivo efficacy of a novel drug eluting paste in glioblastoma.

Methods

Poly(lactic-co-glycolic acid)/poly(ethylene glycol) (PLGA/PEG) self-sintering paste was loaded with the chemotherapeutic agent etoposide and delivered surgically into partially resected tumours in a flank murine glioblastoma xenograft model.

Results

Surgical delivery of the paste was successful and practical, with no toxicity or surgical morbidity to the animals. The paste was retained in the tumour cavity, and preliminary results suggest a useful antitumour and antiangiogenic effect, particularly at higher doses. Bioluminescent imaging was not affected significantly by the presence of the paste in the tumour.

Conclusions

Chemotherapy loaded PLGA/PEG paste seems to be a promising technology capable of delivering active drugs into partially resected tumours. The preliminary results of this study suggest efficacy with no toxicity and will lead to larger scale efficacy studies in orthotopic glioblastoma models.  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