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   2418篇
  免费   137篇
  国内免费   10篇
耳鼻咽喉   18篇
儿科学   98篇
妇产科学   57篇
基础医学   352篇
口腔科学   42篇
临床医学   239篇
内科学   469篇
皮肤病学   155篇
神经病学   123篇
特种医学   171篇
外国民族医学   1篇
外科学   248篇
综合类   67篇
一般理论   1篇
预防医学   192篇
眼科学   58篇
药学   107篇
中国医学   4篇
肿瘤学   163篇
  2023年   13篇
  2022年   53篇
  2021年   78篇
  2020年   66篇
  2019年   68篇
  2018年   86篇
  2017年   57篇
  2016年   55篇
  2015年   56篇
  2014年   86篇
  2013年   103篇
  2012年   144篇
  2011年   164篇
  2010年   145篇
  2009年   123篇
  2008年   138篇
  2007年   133篇
  2006年   97篇
  2005年   120篇
  2004年   83篇
  2003年   59篇
  2002年   67篇
  2001年   22篇
  2000年   18篇
  1999年   23篇
  1998年   45篇
  1997年   46篇
  1996年   44篇
  1995年   37篇
  1994年   27篇
  1993年   24篇
  1992年   9篇
  1990年   12篇
  1989年   19篇
  1988年   16篇
  1987年   13篇
  1986年   15篇
  1985年   10篇
  1984年   20篇
  1983年   17篇
  1982年   15篇
  1981年   14篇
  1980年   18篇
  1979年   8篇
  1978年   13篇
  1977年   14篇
  1976年   13篇
  1975年   11篇
  1974年   14篇
  1970年   10篇
排序方式: 共有2565条查询结果,搜索用时 15 毫秒
31.
The power of medicine has lately enhanced the idea of medicalizing any aspects of life that can be perceived as medical problems. Medicine sometimes creates false needs and there is nowadays an increasing number of situations are medicalized with the pretext of treating fake diseases such as spring fatigue, shyness o natural biological processes like menopause.Despite the better life conditions, we now attend more people that complain about discomfort that may have more to do with «feeling sick» than with authentic disease. There is an endless list: sadness, hyperactive children, anorexia, bulimia, vigorexia or problematic teenagers, amongst others. In this article we revise some interventions that, contribute to promote these situations also from the own doctor's office. Everyday adversity acquires today the status of disease, hence the remarkable increase in these consultations in the diverse sanitary services.  相似文献   
32.

Background

Complete encasement of the inferior vena cava by retroperitoneal tumors is rare. Although replacement of the vena cava has been considered for various conditions in adults, it is rarely used in children except for challenging resections and as a last chance approach – often aiming more at debulking than cure.

Materials and methods

From January 2009 to February 2017, 4 patients (2 adrenal neuroblastomas, 1 renal cell carcinoma, 1 infantile fibrosarcoma) underwent elective en-bloc resection of tumor and of the infrahepatic portion of the inferior vena cava (IVC), with planned IVC prosthetic replacement. In three cases a portion of the left renal vein had to be resected as well, with the vein reanastomosed onto the prosthesis, and a concomitant auto-transplantation of the right kidney was associated in one neuroblastoma patient.

Results

All patients had an uncomplicated postoperative course. In one patient, the prosthetic conduit is patent at long-term (43?months), while the middle portion of the prosthesis did eventually thrombose at mid-term after surgery in the three others – with no related symptoms. Interestingly, all renal venous reconstructions remain patent. Three patients (2 neuroblastomas and 1 infantile fibrosarcoma) are alive and disease-free at 43, 74 and 108?months after surgery, respectively. One patient with renal cell carcinoma died of recurrence of the disease 21?months after surgery.

Conclusion

Resection and reconstruction of the vena cava, including the renal vein portion, can be considered and planned electively in case of tumoral encasement. This strategy is associated with good tolerance of the operation, low morbidity and satisfactory long-term function, even in cases with progressive and/or secondary partial thrombosis.

Level of Evidence

IV  相似文献   
33.
34.

Background  

Human immunodeficiency virus infected individuals are prone to malnutrition due to increased energy requirements, enteropathy and increased catabolism. Trace elements such as zinc and selenium have major role in maintaining a healthy immune system. This study was designed to evaluate the nutritional status of Iranian subjects who were newly diagnosed with human immunodeficiency virus infection and to compare serum level of zinc and selenium in these patients with those of the sex and aged match healthy subjects.  相似文献   
35.
36.
Journal of Thrombosis and Thrombolysis - Although certain risk factors have been associated with morbidity and mortality, validated emergency department (ED) derived risk prediction models specific...  相似文献   
37.

Objective

To determine and compare specific factors that could be associated and predictive with successful prosthetic rehabilitation in major lower-limb amputations.

Methods

A 15-year long (2000–2014) retrospective observational cohort study was conducted. Two different criteria were used to define successful prosthetic rehabilitation: (1) the ability to walk at least 45 m, regardless of assistive devices; and (2) walking >45 m without other ambulatory aids than one cane (if required). Age, gender, comorbidities, cause and level of amputation, stump characteristics, ulcers in the preserved limb, and time between surgery and physical therapy were examined as predictors of successful prosthetic rehabilitation.

Results

A total of 169 patients (61.60 ± 15.9 years) were included. Regarding walking ability with or without walking aids, the presence of ulcers in the preserved limb was individually associated with failed prosthetic rehabilitation (p < 0.001), while being male (OR = 0.21; 95%CI = 0.06–0.80) and transtibial level of amputation (OR = 6.73; 95%CI = 1.92–23.64) were identified as independent predictors of failure and success, respectively. Regarding the criterion of successful rehabilitation, a shorter time until rehabilitation was individually associated with improved walking ability (p < 0.013), while failure could be predicted by comorbidities (OR = 0.48; 95%CI = 0.29–0.78) and age groups of 65–75 years old (OR = 0.19; 95%CI = 0.05–0.78) and over 75 years old (OR = 0.19; 95%CI = 0.04–0.91).

Conclusions

Regarding walking ability with or without walking aids, male gender and transtibial level of amputation are independently associated with failure and success respectively, whereas older age and comorbidities can predict failed prosthetic rehabilitation when assistive walking devices are considered. Future prospective cohort studies are needed to confirm these findings.  相似文献   
38.
背景目前已开展了对重性精神病患者进提供连续性服务的研究。目的探讨基层对有抑郁症风险患者提供连续性服务的水平,并与对心力衰竭患者的服务水平进行对比。方法采用抑郁症风险患者与心力衰竭患者对比的探索性研究。采用患者问卷评估服务的持续性,包含如下内容:(1)联系的服务提供者数(个人连续性);(2)诊所内服务提供者之间的合作(团队连续性)(6个项目,分数1~5分);(3)诊所外全科医师与服务提供者之间的合作(跨界连续性)(4个项目,分数1~5分)。结果大多数抑郁症风险患者在过去1年中寻遍整个服务提供界联系了几个服务提供者,曾遇到过高水平团队连续性服务及低水平跨界连续性服务。在诊所中可接触到的不同服务提供者要明显多于心力衰竭患者服务提供者(P<0.01)。抑郁症风险患者的服务提供者之间的合作更好一些,每项平均得分4.3分,心力衰竭患者得分为4.0分(P=0.03)。然而,跨界连续性服务方面正好相反:抑郁症风险患者每项平均得分3.5分,心力衰竭患者得分为4.0分(P=0.01)。结论抑郁症风险患者与心力衰竭患者之间的探索性对比显示:体验服务连续性方面的差距不大。对此还应行进一步分析。  相似文献   
39.

Objective

To evaluate the effect of quadriceps functional electrical stimulation (FES)-cycling on exertional oxygen uptake (V˙o2) compared with placebo FES-cycling in patients with chronic obstructive pulmonary disease (COPD).

Design

A randomized, single-blind, placebo-controlled crossover trial.

Setting

Pulmonary rehabilitation department.

Participants

Consecutive patients (N=23) with COPD Global Initiative for Chronic Obstructive Lung Disease stage 2, 3, or 4 (mean forced expiratory volume during the first second, 1.4±0.4L [50.3% predicted]) who had recently begun a respiratory rehabilitation program.

Intervention

Two consecutive 30-minute sessions were carried out at a constant load with active and placebo FES-cycling.

Main Outcome Measures

The primary outcome was mean V˙o2 during the 30-minute exercise session. The secondary outcomes were respiratory gas exchange and hemodynamic parameters averaged over the 30-minute endurance session. Lactate values, dyspnea, and perceived muscle fatigue were evaluated at the end of the sessions.

Results

FES-cycling increased the physiological response more than the placebo, with a greater V˙o2 achieved of 36.6mL/min (95% confidence interval [CI], 8.9–64.3mL/min) (P=.01). There was also a greater increase in lactate after FES-cycling (+1.5mmol/L [95% CI, .05–2.9mmol/L]; P=.01). FES-cycling did not change dyspnea or muscle fatigue compared with the placebo condition.

Conclusions

FES-cycling effectively increased exercise intensity in patients with COPD. Further studies should evaluate longer-term FES-cycling rehabilitation programs.  相似文献   
40.
Objective – To evaluate 12‐week changes from baseline of 2 disease‐specific patient‐reported outcome (PRO) measures in adults with migraine treated with galcanezumab, an investigational humanized antibody binding calcitonin gene‐related peptide (CGRP), or placebo. Background – Preventing headache‐related functional impairment is an important goal of migraine preventive treatment and a measurement target for PROs. Understanding which drugs have the potential to improve patient functioning in addition to preventing migraine headaches is vital to lessening patient burden. Design/Methods – This Phase 2b double‐blind, randomized, placebo‐controlled study enrolled adults with episodic migraine. Galcanezumab (120 mg subcutaneous injection; n = 60) or placebo (n = 127) was administered every 28 days for 12 weeks. Post hoc secondary analyses were conducted for those who completed 12 weeks of treatment on 2 PROs: The Migraine‐Specific Quality of Life Questionnaire (MSQ) v2.1 and the Headache Impact Test? (HIT‐6). Results – Analysis of covariance revealed significant differences in least square mean changes from baseline between galcanezumab and placebo for all MSQ domains including total mean change placebo of 18.63, galcanezumab of 27.36 (95% CI 2.449, 15.008; P‐value of .0067); Role Function‐Restrictive mean change placebo of 22.40, galcanezumab of 31.92 (95% CI 2.636, 16.518; P‐value of .0071); Role Function‐Preventive mean change placebo of 13.43, galcanezumab of 19.76 (95% CI 0.476, 12.185; P‐value of .0342); and Emotional Function mean change placebo of 16.88, galcanezumab of 26.61 (95% CI 2.789, 16.674; P‐value of .0063). At baseline, mean number of migraine headache days (MHDs) did not correlate with MSQ total scores or HIT‐6. At 12 weeks post‐treatment, MHD correlated with MSQ and HIT‐6 scores (all < .0001). Change in MHD was associated with change in MSQ domains and change in HIT‐6 scores (all < .0001). Conclusions – In comparison with placebo, treatment with galcanezumab was associated with significant functional improvements as reflected by changes in MSQ scores. Change in MHD was associated with improvements in MSQ and reductions in HIT‐6 scores, indicating the clinical importance of these changes in relation to PROs that measure function.  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