全文获取类型
收费全文 | 800篇 |
免费 | 60篇 |
国内免费 | 1篇 |
专业分类
耳鼻咽喉 | 11篇 |
儿科学 | 13篇 |
妇产科学 | 38篇 |
基础医学 | 95篇 |
口腔科学 | 22篇 |
临床医学 | 125篇 |
内科学 | 127篇 |
皮肤病学 | 30篇 |
神经病学 | 121篇 |
特种医学 | 33篇 |
外科学 | 110篇 |
综合类 | 3篇 |
预防医学 | 42篇 |
眼科学 | 23篇 |
药学 | 39篇 |
肿瘤学 | 29篇 |
出版年
2023年 | 5篇 |
2022年 | 4篇 |
2021年 | 10篇 |
2019年 | 14篇 |
2018年 | 17篇 |
2017年 | 10篇 |
2016年 | 24篇 |
2015年 | 16篇 |
2014年 | 29篇 |
2013年 | 18篇 |
2012年 | 36篇 |
2011年 | 36篇 |
2010年 | 14篇 |
2009年 | 24篇 |
2008年 | 48篇 |
2007年 | 38篇 |
2006年 | 52篇 |
2005年 | 49篇 |
2004年 | 50篇 |
2003年 | 36篇 |
2002年 | 39篇 |
2001年 | 32篇 |
2000年 | 33篇 |
1999年 | 28篇 |
1998年 | 13篇 |
1997年 | 4篇 |
1996年 | 6篇 |
1995年 | 4篇 |
1992年 | 11篇 |
1991年 | 13篇 |
1990年 | 10篇 |
1989年 | 14篇 |
1988年 | 5篇 |
1987年 | 12篇 |
1986年 | 12篇 |
1985年 | 12篇 |
1984年 | 3篇 |
1983年 | 3篇 |
1982年 | 4篇 |
1981年 | 4篇 |
1980年 | 5篇 |
1979年 | 7篇 |
1978年 | 6篇 |
1977年 | 3篇 |
1976年 | 3篇 |
1975年 | 6篇 |
1973年 | 8篇 |
1972年 | 4篇 |
1971年 | 3篇 |
1967年 | 6篇 |
排序方式: 共有861条查询结果,搜索用时 31 毫秒
1.
Fernanda Jorge Guimarães Lorita Marlena Freitag Pagliuca 《Disability and rehabilitation. Assistive technology》2019,14(3):236-240
Purpose: To validate the assistive technology “Drugs: reflection for prevention” to be used with visually impaired people.Method: Quantitative and quasi-experimental study, contrasting knowledge before and after the use of the assistive technology with 140 visually impaired people in institutes and associations for people with visual impairment. A questionnaire with identification data, a pre-test, a post-test and a questionnaire to assess the assistive technology were applied. Data were described through means and standard deviations, and analyses included the McNemar test, the exact binomial distribution test, and the intraclass correlation coefficient.Results: Participants were male (65.7%), 84.3% were blind, aged 37.1?years on average and with schooling of 10.1?years on average. There were more correct answers in the post-test (p?<.001). The attributes of the assistive technology were considered adequate: objectives, access, clarity, structure and presentation, relevance and efficacy, and interactivity (p?<.001).Conclusions: The assistive technology “Drugs: reflection for prevention” was considered valid and reliable to inform visually impaired people about psychoactive substance abuse.
- Implications for rehabilitation
Created new tool for prevention substance abuse that can be accessed easily.
Improved information about substance psychoactive for users of the assistive technology.
Improved quality of life for its users.
2.
3.
Tobias Hüppe Sascha Kreuer Hinnerk Wulf Dennik Freitag Martin Seidel Tobias Teucke Felix Maurer Andreas Kirschbaum Tilo Koch Frank Langer Thomas Volk Carsten Feldmann 《Acta anaesthesiologica Scandinavica》2023,67(4):455-461
Background
Volatile propofol can be measured in exhaled air and correlates to plasma concentrations with a time delay. However, the effect of single-lung ventilation on exhaled propofol is unclear. Therefore, our goal was to evaluate exhaled propofol concentrations during single-lung compared to double-lung ventilation using double-lumen tubes.Methods
In a first step, we quantified adhesion of volatile propofol to the inner surface of double-lumen tubes during double- and single-lumen ventilation in vitro. In a second step, we enrolled 30 patients scheduled for lung surgery in two study centers. Anesthesia was provided with propofol and remifentanil. We utilized left-sided double-lumen tubes to separately ventilate each lung. Exhaled propofol concentrations were measured at 1-min intervals and plasma for propofol analyses was sampled every 20 min. To eliminate the influence of dosing on volatile propofol concentration, exhalation rate was normalized to plasma concentration.Results
In-vitro ventilation of double-lumen tubes resulted in increasing propofol concentrations at the distal end of the tube over time. In vitro clamping the bronchial lumen led to an even more pronounced increase (Δ AUC +62%) in propofol gas concentration over time. Normalized propofol exhalation during lung surgery was 31% higher during single-lung compared to double-lung ventilation.Conclusion
During single-lung ventilation, propofol concentration in exhaled air, in contrast to our expectations, increased by approximately one third. However, this observation might not be affected by change in perfusion-ventilation during single-lung ventilation but rather arises from reduced propofol absorption on the inner surface area of the double-lumen tube. Thus, it is only possible to utilize exhaled propofol concentration to a limited extent during single-lung ventilation.Registration of Clinical Trial
DRKS-ID DRKS00014788 ( www.drks.de ). 相似文献4.
PURPOSE: To evaluate the capacity of a novel oral water irrigator to remove established plaque deposits. METHODS: The study was designed as a randomized two-treatment, crossover, examiner-blinded clinical trial. The plaque removing capability of a prototype oral irrigator was compared to a conventional electric toothbrush. After 48 hours of plaque accumulation the 35 subjects were randomly assigned to professional plaque removal by either oral irrigation or by electric toothbrushing for a timed 2-minute total cleaning. Pre- and post cleaning plaque was disclosed and gingival abrasions were identified. Plaque was assessed on gingival and approximal surfaces of the oral and buccal sites according to the Rustogi et al modification of the Modified Navy Plaque Index. The assessment of gingival abrasions was performed according to the method introduced by Danser et al. RESULTS: The overall plaque removing capacity of the oral irrigator reached approximately 40.7 +/- 16.7% as compared to 71.6 +/- 11.5% by the electric toothbrush. Similar effects were observed for the gingival and approximal areas. The electric toothbrush caused significantly more gingival abrasions than the oral irrigator. 相似文献
5.
6.
STATEMENT OF PROBLEM: Various machinable materials are currently used with computer-aided design/computer-assisted manufacturing (CAD/CAM) technologies for the chairside fabrication of restorations. However, properties of these new machinable materials, such as fracture load, wear, marginal deterioration, and color stability, should be investigated in vitro under replicated clinical conditions prior to time-consuming clinical studies. PURPOSE: This study investigated the effect of cyclic loading fatigue and different luting agents under wet conditions on the fracture load of CAD/CAM machined composite resin and all-ceramic crowns. MATERIALS AND METHODS: Ninety-six intact human maxillary premolars were prepared for composite resin and all-ceramic crowns with the following preparation criteria: 6-degree axial taper, 1.5-mm shoulder finish line placed 0.5 mm occlusal to the cemento-enamel junction, 1.5-mm axial reduction, 2-mm occlusal reduction, and 5-mm occluso-gingival height. Sixteen unprepared premolars served as controls. Forty-eight all-ceramic crowns (Vita Mark II) and 48 millable composite resin crowns (MZ100 Block) were fabricated using a CAD/CAM system (Cerec 3). Three luting agents-RelyX ARC (RX), GC Fuji CEM (FC), and zinc phosphate cement (ZP)-were used for cementation (n = 16). After 1-week storage in water, half of the specimens (n=8) in each subgroup were cyclically loaded and thermal cycled under wet conditions for 600,000 masticatory cycles and 3500 thermal cycles (58 degrees C/4 degrees C; dwell time, 60 seconds) in a masticatory simulator; the other half (n = 8) were fractured without cyclic loading. All specimens were loaded in a universal testing machine with a compressive load (N) applied along the long axis of the specimen at a crosshead speed of 1 mm/min until fracture. Fracture loads (N) were recorded for each specimen. Three-way analysis of variance was used to detect the effects of the experimental factors (crown material, luting agent, and loading conditions) on the fracture load. The comparison with the unprepared natural teeth as controls was done by means of t tests (alpha=.05). RESULTS: Analysis of variance revealed a statistically significant influence of the luting agent and the cyclic loading (P < .001), whereas the crown material had no significant influence. Cyclic loading fatigue significantly decreased the mean fracture load of test groups independent of the 3 luting agents used: MZ100/ZP, 827.1 to 552.5 N; MZ100/FC, 914.7 to 706.2 N; MZ100/RX, 955.9 to 724.4 N; Vita/ZP, 772.3 to 571.5 N; Vita/FC, 923.6 to 721.1 N; and Vita/RX, 929.1 to 752.7 N. However, there was no significant difference in the mean fracture load of control specimens before and after cyclic loading (1140.1 N and 1066.2 N, respectively). Adhesive luting agents RelyX ARC and GC Fuji CEM increased fracture load significantly compared to zinc phosphate cement. CONCLUSIONS: Cyclic loading fatigue significantly reduced the fracture loads of composite resin and all-ceramic crowns, whereas adhesive cementation significantly increased the fracture loads. 相似文献
7.
Cook D Douketis J Meade M Guyatt G Zytaruk N Granton J Skrobik Y Albert M Fowler R Hebert P Pagliarello G Friedrich J Freitag A Karachi T Rabbat C Heels-Ansdell D Geerts W Crowther M;Canadian Critical Care Trials Group 《Critical care (London, England)》2008,12(2):R32-9
Background
Critically ill patients with renal insufficiency are predisposed to both deep vein thrombosis (DVT) and bleeding. The objective of the present study was to evaluate the prevalence, incidence and predictors of DVT and the incidence of bleeding in intensive care unit (ICU) patients with estimated creatinine clearance <30 ml/min.Methods
In a multicenter, open-label, prospective cohort study of critically ill patients with severe acute or chronic renal insufficiency or dialysis receiving subcutaneous dalteparin 5,000 IU once daily, we estimated the prevalence of proximal DVT by screening compression venous ultrasound of the lower limbs within 48 hours of ICU admission. DVT incidence was assessed on twice-weekly ultrasound testing. We estimated the incidence of major and minor bleeding by daily clinical assessments. We used Cox proportional hazards regression to identify independent predictors of both DVT and major bleeding.Results
Of 156 patients with a mean (standard deviation) creatinine clearance of 18.9 (6.5) ml/min, 18 had DVT or pulmonary embolism within 48 hours of ICU admission, died or were discharged before ultrasound testing – leaving 138 evaluable patients who received at least one dose of dalteparin. The median duration of dalteparin administration was 7 days (interquartile range, 4 to 12 days). DVT developed in seven patients (5.1%; 95% confidence interval, 2.5 to 10.1). The only independent risk factor for DVT was an elevated baseline Acute Physiology and Chronic Health Evaluation II score (hazard ratio for 10-point increase, 2.25; 95% confidence interval, 1.03 to 4.91). Major bleeding developed in 10 patients (7.2%; 95% confidence interval, 4.0 to 12.8), all with trough anti-activated factor X levels ≤ 0.18 IU/ml. Independent risk factors for major bleeding were aspirin use (hazard ratio, 6.30; 95% confidence interval, 1.35 to 29.4) and a high International Normalized Ratio (hazard ratio for 0.5-unit increase, 1.68; 95% confidence interval, 1.07 to 2.66).Conclusion
In ICU patients with renal insufficiency, the incidence of DVT and major bleeding are considerable but appear related to patient comorbidities rather than to an inadequate or excessive anticoagulant from thromboprophylaxis with dalteparin.Clinical Trial Registration
Number NCT00138099. 相似文献8.
Korreliert die Patientenzufriedenheit mit dem Schmerzniveau bei der Anwendung von patientenkontrollierter Epiduralanalgesie? 总被引:1,自引:0,他引:1
Gottschalk A Freitag M Liehr K Domke A Schuster M Standl T 《Schmerz (Berlin, Germany)》2004,18(2):145-150
INTRODUCTION: The evaluation of patients' satisfaction and outcome after surgery is of increasing importance. An optimized postoperative pain management may contribute substantially to this important goal. METHODS: After approval of the local ethics committee and written informed consent, 150 adult patients receiving epidural catheters for postoperative pain management were evaluated over 1 week postoperatively with respect to their satisfaction with the pain therapy and incidence of side effects. All patients received a continuous epidural infusion with ropivacaine 0.2% plus sufentanil 0.5 microg/ml via a PCEA pump (basal rate 6-8 ml/h, bolus 2 ml, lockout time 5 min). For assessment of pain the VAS scale (0-100 mm) was used, and patients' satisfaction was evaluated using a numeric rating scale (1-6, 1=very good, 6=very dissatisfied). RESULTS: Of the patients, 95 were operated in general surgery, 32 in orthopedics, and 23 in gynecology. Time of treatment with epidural catheters (71% thoracic, 29% lumbar catheters) was 5.1 +/- 2.9 days. Of the patients, 87.8% evaluated the postoperative pain service as very good or good, and 89% of the patients would choose the same pain therapy again. Side effects mainly consisted in bladder dysfunction (19%) and intermittent motor blockade (18%) especially with lumbar catheters. Correlation between patient satisfaction and the remembered maximum pain levels was low ( r=0.266). CONCLUSION: Evaluation of patients' satisfaction with postoperative epidural pain therapy resulted in a high degree of satisfaction without correlation between patients' satisfaction and recalled maximum pain levels. These results, including side effects and special problems during pain therapy, provide motivation to further improve postoperative pain management. 相似文献
9.
LY293558, a novel AMPA/GluR5 antagonist, is efficacious and well-tolerated in acute migraine 总被引:2,自引:0,他引:2
Sang CN Ramadan NM Wallihan RG Chappell AS Freitag FG Smith TR Silberstein SD Johnson KW Phebus LA Bleakman D Ornstein PL Arnold B Tepper SJ Vandenhende F 《Cephalalgia : an international journal of headache》2004,24(7):596-602
Glutamatergic hyperactivity is implicated migraine pathogenesis. Also, LY293558, an alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)/kainate (KA) receptor antagonist, is effective in preclinical models of migraine. We therefore tested LY293558 in acute migraine. We conducted a randomized, triple-blind, parallel-group, double-dummy, multicentre trial of 1.2 mg/kg intravenous (IV) LY293558, 6 mg subcutaneous (SC) sumatriptan, or placebo in the treatment of acute migraine. The primary efficacy variable was the headache response rate, i.e. headache score improvement from moderate/severe at baseline to mild/none at 2 h. Of 45 enrolled patients, 44 patients (20M:24F; mean age +/- SD = 40 +/- 9 years) completed the study. Response rates were 69% for LY293558 (P = 0.017 vs. placebo), 86% for sumatriptan (P < 0.01 vs. placebo) and 25% for placebo. LY293558 and sumatriptan were superior to placebo (P < 0.01 for all comparisons) on all other measures of improvement in pain and migraine associated symptoms. Fifteen percent of patients who took LY293558 reported adverse events (AEs) (n = 2; one mild, one severe). Fifty-three percent of patients who took sumatriptan (n = 8; seven mild, one moderate) and 31% of those who received placebo reported AEs (n = 5; four mild, one severe). The efficacy and safety results of LY293558 in this small migraine proof of concept trial, together with supportive preclinical data, provide evidence for a potential role of nonvasoactive AMPA/KA antagonists in treating migraine. Larger trials are needed to further test the hypothesis. 相似文献
10.
Frank E Liu J Kinasewitz G Moran GJ Oross MP Olson WH Reichl V Freitag S Bahal N Wiesinger BA Tennenberg A Kahn JB 《Clinical therapeutics》2002,24(8):1292-1308
BACKGROUND: Changing etiologic patterns and the growing problem of antimicrobial resistance, particularly an increase in macrolide-resistant pneumococcal bacteremia, are causing physicians to adopt new approaches to the treatment of community-acquired pneumonia (CAP). OBJECTIVE: The relative efficacy and tolerability of levofloxacin monotherapy and azithromycin and ceftriaxone combination therapy were assessed in hospitalized adults with moderate to severe CAP. METHODS: This Phase IV, multicenter, open-label, randomized trial compared 2 treatment regimens: (1) levofloxacin 500 mg PO or IV q24h, and (2) azithromycin 500 mg IV q24h for > or = 2 days plus ceftriaxone 1 g IV q24h for 2 days, followed by an optional transition to azithromycin 500 mg PO q24h at the investigator's discretion. The total duration of therapy was to be a minimum of 10 days in both treatment groups. Ceftriaxone was included in the initial azithromycin regimen to ensure coverage against pneumococcal bacteremia. RESULTS: Of 236 patients in the intent-to-treat population, completion or withdrawal information was available for 110 patients in the levofloxacin group and 114 in the azithromycin group. Baseline demographic and disease characteristics were comparable between groups. At the end of treatment, the clinical success rate (cured + improved) in clinically evaluable patients was 94.1% in the levofloxacin group and 92.3% in the azithromycin group. The respective posttherapy microbiologic eradication rates were 89.5% and 92.3%. Levofloxacin was as well tolerated as azithromycin, with an incidence of drug-related adverse events (AEs) for all body systems of 5.3% and 9.3%, respectively. None of the drug-related AEs were considered serious [corrected]. CONCLUSIONS: In this study in hospitalized patients with moderate to severe CAP, levofloxacin monotherapy was at least as effective as a combination regimen of azithromycin and ceftriaxone in providing coverage against the current causative pathogens in CAP. In addition, levofloxacin was as well tolerated as the combination of azithromycin and ceftriaxone. 相似文献