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   9775篇
  免费   412篇
  国内免费   134篇
耳鼻咽喉   15篇
儿科学   188篇
妇产科学   9篇
基础医学   607篇
口腔科学   98篇
临床医学   1044篇
内科学   335篇
皮肤病学   3篇
神经病学   100篇
特种医学   859篇
外科学   4886篇
综合类   1111篇
预防医学   294篇
眼科学   130篇
药学   354篇
  7篇
中国医学   224篇
肿瘤学   57篇
  2024年   29篇
  2023年   165篇
  2022年   379篇
  2021年   508篇
  2020年   430篇
  2019年   400篇
  2018年   343篇
  2017年   324篇
  2016年   333篇
  2015年   317篇
  2014年   709篇
  2013年   627篇
  2012年   576篇
  2011年   596篇
  2010年   485篇
  2009年   512篇
  2008年   492篇
  2007年   433篇
  2006年   387篇
  2005年   399篇
  2004年   297篇
  2003年   218篇
  2002年   187篇
  2001年   168篇
  2000年   132篇
  1999年   133篇
  1998年   104篇
  1997年   106篇
  1996年   67篇
  1995年   62篇
  1994年   53篇
  1993年   41篇
  1992年   41篇
  1991年   31篇
  1990年   18篇
  1989年   15篇
  1988年   28篇
  1987年   28篇
  1986年   9篇
  1985年   18篇
  1984年   17篇
  1983年   11篇
  1982年   11篇
  1981年   11篇
  1980年   11篇
  1979年   8篇
  1978年   16篇
  1977年   18篇
  1976年   7篇
  1975年   4篇
排序方式: 共有10000条查询结果,搜索用时 390 毫秒
131.
目的:探讨聚焦式体外冲击波联合离心锻炼治疗股骨大转子疼痛综合征的临床疗效。方法:2017年9月至2019年6月,将符合研究标准的53例股骨大转子疼痛综合征(greater trochanteric pain syndrome,GTPS)的患者分为观察组(29例)和对照组(24例)。观察组,男8例,女21例,年龄38~62(49.96±6.39)岁,病程6~13(8.58±1.99)个月,采用聚焦式体外冲击波联合离心锻炼治疗;对照组,男5例,女19例,年龄39~62(52.79±5.86)岁,病程6~14(9.04±2.51)个月,单纯采用离心锻炼治疗。分别使用疼痛视觉模拟评分(visual analogue scale,VAS)和髋关节Harris评分评估两组患者治疗前及治疗后1、2、6个月时髋部疼痛缓解程度及髋关节功能恢复情况,比较治疗效果。结果:治疗后1个月,两组VAS、髋关节Harris评分及治疗成功率比较差异无统计学意义(P>0.05);2个月时,观察组VAS (3.20±0.81)分低于对照组的(3.87±0.61)分(P<0.05),髋关节Harris评分(81.93±2.43)分与对照组(82.12±2.34)分比较差异无统计学意义(P=0.770),治疗成功率(58.62%,17/29)高于对照组(29.16%,7/24)(P=0.032);6个月时,观察组VAS (2.24±0.68)分低于对照组的(3.12±0.53)分(P<0.001),髋关节Harris评分(85.10±1.75)分高于对照组的(83.66±1.78)分(P=0.005),治疗成功率(82.75%,24/29)与对照组(62.50%,15/24)比较差异无统计学意义(P=0.096)。结论:聚焦式体外冲击波联合离心锻炼能够显著缓解大转子疼痛综合征患者髋部疼痛症状,改善髋关节功能,安全性可靠,值得在临床实践中应用推广。  相似文献   
132.
133.
Background: Hand fractures and dislocations are common injuries in the pediatric population. This study aims to characterize the pediatric hand injuries that required closed reduction and identify those that required multiple reduction attempts. Methods: A retrospective cohort study was carried out in patients younger than 18 years of age with hand fractures or dislocations who underwent closed reduction in the emergency department (ED). Patients who ultimately required surgical reduction and fixation were not included. Results: Of the 310 hand injuries identified, 148 (114 fractures and 34 dislocations) underwent closed reduction in the ED; 7.4% of those required repeat reduction. Hand injuries that most often required repeat reduction included metacarpophalangeal joint dislocations (20.0%) and proximal phalanx neck (16.7%), metacarpal shaft (15.4%), metacarpal neck (6.2%), and proximal phalanx base (5.6%) fractures. No modifiable risk factors predicting the need for repeat reduction were identified. Conclusions: Some pediatric hand injuries are more likely to require repeat closed reduction by a hand surgeon. This retrospective study is the first step toward quality improvement as it provides opportunities for further research into the factors contributing to reductions that are unsuccessful at the first attempt. Identification of these factors and implementation of quality improvement measures are necessary to ensure the effective treatment of all pediatric hand injuries.  相似文献   
134.
ObjectiveTo compare the clinical efficacy of the direct anterior approach in lateral decubitus position (L‐DAA) and supine position (S‐DAA) for unilateral total hip arthroplasty.MethodsA retrospective study was conducted on 89 patients who underwent primary unilateral total hip arthroplasty in our department between August 2016 and December 2017. There were 46 patients who underwent L‐DAA and 43 patients who underwent S‐DAA. The body mass index (BMI), operation time, blood loss, preoperative Hb, first day and third day postoperative Hb, incision length, hospital stay, preoperative and postoperative Harris score, preoperative and postoperative visual analogue scale (VAS) score, radiological evaluation, intraoperative and postoperative complication, postoperative absolute length difference of lower extremity were recorded and analyzed. P < 0.05 was set as the significant difference.ResultsAll patients were followed up for 8–23 months, with an average of 15.6 months. No significant differences were found in preoperative and postoperative Harris scores, preoperative Hb, incision lengths, radiological evaluations, preoperative and postoperative VAS scores, and hospital stay (P > 0.05). However, significant differences were detected in BMI, blood loss, first day and third day postoperative Hb, and operation time (P < 0.05). There were no postoperative complications in the L‐DAA and S‐DAA groups. During the operation, two cases of proximal femoral fracture occurred in the L‐DAA group, four in the S‐DAA group, and the difference was statistically significant. There were significant differences found in the postoperative absolute length difference of lower extremity between the two groups.ConclusionCompared with the S‐DAA approach, the L‐DAA approach had the advantages of shorter operation time and less blood loss. Compared with S‐DAA, it was easier to expose the proximal femur, and lower BMI was required in L‐DAA. However, it was more difficult to compare the length of both lower extremities in the L‐DAA approach than in the S‐DAA approach.  相似文献   
135.
The aim of the present paper was to identify, appraise, and synthesize the available evidence on two‐stage revision hip arthroplasty with or without the use of an interim spacer for managing late prosthetic infection. The review methodology was designed by referencing the Preferred Reporting Items for Systematic Reviews and Meta‐analyses (PRISMA) checklist and flow diagram, and a Population, Intervention, Comparator, Outcomes and Study (PICOS) design framework was used to search for studies to incorporate within the review. Two independent investigators were involved in searching for relevant articles that fulfilled the inclusion criteria for the study. Critical appraisal of the selected articles was carried out using the relevant Critical Appraisal Skills Programme checklists. From an initial pool of 125 articles, four studies satisfied the inclusion criteria and quality assessment and were included for final review. Two patient groups were identified from within the selected studies: spacer and non‐spacer. Both groups were assessed in terms of functional outcome, infection cure rates, and technical difficulties encountered during treatment. Better functional outcome was reported in the spacer group, both in the interim period between the two stages and after completion of treatment. The use of spacers reduced operative difficulty during the second stage and accelerated patient discharge. Reinfection and infection persistence rates were higher in the non‐spacer group. Within the spacer group, articulated spacers performed better in all parameters. The results of this review reinforce the available evidence supporting the use of interim hip spacers in revision hip arthroplasty for managing prosthetic infection and also indicate that articulated hip spacers could be an attractive option going forward.  相似文献   
136.
ObjectiveTo investigate the risk factors for, and outcomes of, preoperative asymptomatic pulmonary embolism (PE) in patients ≥60 years old following delayed operation for hip fracture.MethodsFrom March 2017 to December 2018, 90 patients aged ≥60 years with hip fracture who suffered a delay in surgery were recruited to this prospective study following admission to our hospital. Computed tomography pulmonary angiography (CTPA) was used to detect preoperative asymptomatic PE and calculated its incidence. Time from injury to admission, baseline characteristics, medical comorbidities, and blood biomarker levels were evaluated as potential risk factors. Logistic regression analysis was used to identify risk factors. Mortality and major bleeding events were recorded and compared between individuals with PE and without. Data were analyzed by t‐test, Mann–Whitney U test, χ 2 test, Fisher''s exact test, and logistic regression analysis.ResultsThe incidence of preoperative asymptomatic PE was 18.9% (17/90 patients). In the univariate analysis, the risk factors for preoperative asymptomatic PE were male sex, hypertension, cerebrovascular accident, smoking, plasma D‐dimer level, potassium level, urea level, creatinine level, and cysteine level. Multivariate logistic regression analysis showed that the risk of preoperative asymptomatic PE was higher in patients with hypertension (odds ratio [OR] = 10.048; 95% confidence interval [CI], 1.118–90.333), cerebrovascular accident (OR = 20.135; 95% CI, 1.875–216.164), smoking (OR = 48.741; 95% CI, 4.155–571.788), high plasma D‐dimer levels (OR = 1.200; 95% CI, 1.062–157.300), and high plasma potassium levels (OR = 12.928; 95% CI, 1.062–157.300). All patients were followed up for 21.0 months (range, 2 to 36 months). Mortality within the first year postoperatively was higher in patients with PE (29.41% vs 9.59%, P = 0.046).ConclusionsIn view of the high incidence of preoperative asymptomatic PE and the inferior prognosis in individuals with PE, routine CTPA examination for preoperative asymptomatic PE could be useful for patients aged ≥60 years with hip fracture for whom surgery is delayed.  相似文献   
137.
BACKGROUNDTimely intervention in hip fracture is essential to decrease the risks of perioperative morbidity and mortality. However, limitations of the resources, risk of disease transmission and redirection of medical attention to a more severe infective health problem during coronavirus disease 2019 (COVID-19) pandemic period have affected the quality of care even in a surgical emergency.AIMTo compare the 30-d mortality rate and complications of hip fracture patients treated during COVID-19 pandemic and pre-pandemic times.METHODSThe search of electronic databases on 1st August 2020 revealed 45 studies related to mortality of hip fracture during the COVID-19 pandemic and pre-pandemic times. After careful screening, eight studies were eligible for quantitative and qualitative analysis of data.RESULTSThe pooled data of eight studies (n = 1586) revealed no significant difference in 30-d mortality rate between the hip fracture patients treated during the pandemic and pre-pandemic periods [9.63% vs 6.33%; odds ratio (OR), 0.62; 95%CI, 0.33, 1.17; P = 0.14]. Even the 30-d mortality rate was not different between COVID-19 non-infected patients who were treated during the pandemic time, and all hip fracture patients treated during the pre-pandemic period (OR, 1.03; 95%CI, 0.61, 1.75; P = 0.91). A significant difference in mortality rate was observed between COVID-19 positive and COVID-19 negative patients (OR, 6.99; 95%CI, 3.45, 14.16; P < 0.00001). There was no difference in the duration of hospital stay (OR, -1.52, 95%CI, -3.85, 0.81; P = 0.20), overall complications (OR, 1.62; P = 0.15) and incidence of pulmonary complications (OR, 1.46; P = 0.38) in these two-time frames. Nevertheless, the preoperative morbidity was more severe, and there was less use of general anesthesia during the pandemic time.CONCLUSIONThere was no difference in 30-d mortality rate between hip fracture patients treated during the pandemic and pre-pandemic periods. However, the mortality risk was higher in COVID-19 positive patients compared to COVID-19 negative patients. There was no difference in time to surgery, complications and hospitalization time between these two time periods.  相似文献   
138.
BACKGROUNDMaximum surgical blood order schedules were designed to eliminate unnecessary preoperative crossmatching prior to surgery in order to conserve blood bank resources. Most protocols recommend type and cross of 2 red blood cell (RBC) units for patients undergoing surgery for treatment of hip fracture. Preoperative hemoglobin has been identified as the strongest predictor of inpatient transfusion, but current maximum surgical blood order schedules do not consider preoperative hemoglobin values to determine the number of RBC units to prepare prior to surgery. AIMTo determine the preoperative hemoglobin level resulting in the optimal 2:1 crossmatch-to-transfusion (C:T) ratio in hip fracture surgery patients.METHODSIn 2015 a patient blood management (PBM) program was implemented at our institution mandating a single unit-per-occurrence transfusion policy and a restrictive transfusion threshold of < 7 g/dL hemoglobin in asymptomatic patients and < 8 g/dL in those with refractory symptomatic anemia or history of coronary artery disease. We identified all hip fracture patients between 2013 and 2017 and compared the preoperative hemoglobin which would predict a 2:1 C:T ratio in the pre PBM and post PBM cohorts. Prediction profiling and sensitivity analysis were performed with statistical significance set at P < 0.05. RESULTSFour hundred and ninety-eight patients who underwent hip fracture surgery between 2013 and 2017 were identified, 291 in the post PBM cohort. Transfusion requirements in the post PBM cohort were lower (51% vs 33%, P < 0.0001) than in the pre PBM cohort. The mean RBC units transfused per patient was 1.15 in the pre PBM cohort, compared to 0.66 in the post PBM cohort (P < 0.001). The 2:1 C:T ratio (inpatient transfusion probability of 50%) was predicted by a preoperative hemoglobin of 12.3 g/dL [area under the curve (AUC) 0.78 (95% confidence interval (CI), 0.72-0.83), Sensitivity 0.66] in the pre PBM cohort and 10.7 g/dL [AUC 0.78 (95%CI, 0.73-0.83), Sensitivity 0.88] in the post PBM cohort. A 50% probability of requiring > 1 RBC unit was predicted by 11.2g/dL [AUC 0.80 (95%CI, 0.74-0.85), Sensitivity 0.87] in the pre PBM cohort and 8.7g/dL [AUC 0.78 (95%CI, 0.73-0.83), Sensitivity 0.84] in the post-PBM cohort.CONCLUSIONThe hip fracture maximum surgical blood order schedule should consider preoperative hemoglobin in determining the number of units to type and cross prior to surgery.  相似文献   
139.
基于网络的人工髋关节术后评定系统   总被引:3,自引:0,他引:3  
目的 对人工髋关节置换术后的效果进行评定。方法 采用了三种著名的人工髋关节置换术评定标准 ,利用网络技术和计算机对数据进行采集整理和分析。结果 完成了评定系统的功能 ,能得出正确的结论。结论 采用基于网络的人工髋关节评定系统提高评定的速度和质量 ,其评定结果可方便的进行交流  相似文献   
140.
Summary Based on the geometric model developed by Netter [11], we determined the different positions of the femoral neck during monopodal support in walking in relation to a fixed frontal plane of reference (relative anteversion). This relative anteversion ranges on average from 24° of retroversion at the beginning of support to 15° of anterversion at the end if loading. We then studied the relations possibly existing between relative anteversion and acetabular orientation on the one hand, and the orientation of the resultant of the articular stresses on the other (both being variables during monopodal support in walking). The results showed that relative anteversion is well correlated with variations of position of the acetabulum since, at most, the deviation between the respective axes did not exceed the anatomic deviation due to absolute anteversion of the femoral neck and acetabulum. Lastly, analysis of the relations obtained with the orientation of the resultant of the articular stresses allowed a better comprehension of the functional distribution of forces.
Variations de l'antéversion relative du col fémoral au cours de la marche
Résumé Nous inspirant de la modélisation géométrique développée par R. Netter dans sa thèse, nous avons déterminé les différentes positions du col fémoral au cours de l'appui monopodal de la marche par rapport à un plan frontal fixe de référence (antéversion relative). Cette «antéversion relative» s'échelonne en moyenne de 24° de rétroversion en début d'appui à 15° d'antéversion en fin d'appui. Nous avons alors étudié les relations pouvant exister entre l'antéversion relative et l'orientation de l'acétabulum, d'une part, et, d'autre part, l'orientation de la résultante des sollicitations articulaires (toutes deux variables au cours de l'appui monopodal de la marche). Les résultats nous ont montré que l'antéversion relative est bien corrélée aux variations de position de l'acétabulum puisque, au maximum, l'écart entre leurs axes respectifs ne dépasse pas l'écart anatomique du à l'antéversion absolue du col et de l'acétabulum. Enfin, l'analyse des rapports existant avec l'orientation de la résultante des sollicitations articulaires nous permet de mieux entrevoir la répartition fonctionnelle des contraintes.
  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