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BACKGROUND CONTEXT
Lumbar spinal stenosis (LSS) can impair blood flow to the spinal nerves giving rise to neurogenic claudication and limited walking ability. Reducing lumbar lordosis can increases the volume of the spinal canal and reduce neuroischemia. We developed a prototype LSS belt aimed at reducing lumbar lordosis while walking.PURPOSE
The aim of this study was to assess the short-term effectiveness of a prototype LSS belt compared to a lumbar support in improving walking ability in patients with degenerative LSS.STUDY DESIGN
This was a two-arm, double-blinded (participant and assessor) randomized controlled trial.PATIENT SAMPLE
We recruited 104 participants aged 50 years or older with neurogenic claudication, imaging confirmed degenerative LSS, and limited walking ability.OUTCOME MEASURES
The primary measure was walking distance measured by the self-paced walking test (SPWT) and the primary outcome was the difference in proportions among participants in both groups who achieved at least a 30% improvement in walking distance from baseline using relative risk with 95% confidence intervals.METHODS
Within 1 week of a baseline SPWT, participants randomized to the prototype LSS belt group (n=52) and those randomized to the lumbar support group (n=52) performed a SPWT that was conducted by a blinded assessor. The Arthritis Society funded this study ($365,000 CAN) with salary support for principal investigator funded by the Canadian Chiropractic Research Foundation ($500,000 CAN for 5 years).RESULTS
Both groups showed significant improvement in walking distance, but there was no significant difference between groups. The mean group difference in walking distance was ?74 m (95% CI: ?282.8 to 134.8, p=.49). In total, 62% of participants wearing the prototype LSS belt and 82% of participants wearing the lumbar support achieved at least 30% improvement in walking distance (relative risk, 0.7; 95% CI: 0.5–1.3, p=.43).CONCLUSIONS
A prototype LSS belt demonstrated significant improvement in walking ability in degenerative LSS but was no better than a lumbar support. 相似文献Background
With the worldwide spread of antibiotic resistance, delivering antibiotic susceptibility test (AST) results in a timely manner represents a major challenge. In cases of sepsis, rapid AST may facilitate early optimization of empiric antibiotic therapy. Disc diffusion is a well-standardized AST method, however 16 to 24?h are required to achieve an overall AST profile according to antimicrobial societies.Methods
In this prospective pilot study, we evaluated the performance of Mueller-Hinton-Rapid-SIR (MHR-SIR) agar after 6–8?h of incubation in comparison with standard MH agar after 16?h of incubation directly on positive blood cultures caused by Enterobacteriaceae and Staphylococcus aureus from routine clinical microbiology.A total of 133 positive blood samples including 110 Enterobacteriaceae (83%) and 23 Staphylococcus aureus (17%) were tested in parallel by two direct AST methods, each using EUCAST breakpoints. For each combination bacterium and antibiotic, we compared the categorical agreement and the correlation between the diameters obtained by MHR-SIR and by standard MH.Results
Our results showed 97.7% categorical agreement for Enterobacteriaceae, with 1.4% minor errors, 0.4% major errors and 0.5% very major errors. For S. aureus, we observed 97.8% categorical agreement, 1.9% minor errors, 0.3% major errors and no very major errors.Conclusion
Our results showed excellent categorical agreement and correlations between diameters for MHR-SIR and standard MH methods. MHRSIR can predict the result of overall AST profile within 6–8?h with reliable results. AST is obtained on the same day the blood culture becomes positive, with a very moderate cost. 相似文献Prolonged mechanical ventilation (MV) is a major complication following cardiac surgery. We conducted a secondary analysis of the Transfusion Requirements in Cardiac Surgery (TRICTS) III trial to describe MV duration, identify factors associated with prolonged MV, and examine associations of prolonged MV with mortality and complications.
MethodsFour thousand, eight hundred and nine participants undergoing cardiac surgery at 71 hospitals worldwide were included. Prolonged MV was defined based on the Society of Thoracic Surgeons definition as MV lasting 24 hr or longer. Adjusted associations of patient and surgical factors with prolonged MV were examined using multivariable logistic regression. Associations of prolonged MV with complications were assessed using odds ratios, and adjusted associations between prolonged MV and mortality were evaluated using multinomial regression. Associations of shorter durations of MV with survival and complications were explored.
ResultsProlonged MV occurred in 15% (725/4,809) of participants. Prolonged MV was associated with surgical factors indicative of complexity, such as previous cardiac surgery, cardiopulmonary bypass duration, and separation attempts; and patient factors such as critical preoperative state, left ventricular impairment, renal failure, and pulmonary hypertension. Prolonged MV was associated with perioperative but not long-term complications. After risk adjustment, prolonged MV was associated with perioperative mortality; its association with long-term mortality among survivors was weaker. Shorter durations of MV were not associated with increased risk of mortality or complications.
ConclusionIn this substudy of the TRICS III trial, prolonged MV was common after cardiac surgery and was associated with patient and surgical risk factors. Although prolonged MV showed strong associations with perioperative complications and mortality, it was not associated with long-term complications and had weaker association with long-term mortality among survivors.
Study registrationwww.ClinicalTrials.gov (NCT02042898); registered 23 January 2014. This is a substudy of the Transfusion Requirements in Cardiac Surgery (TRICS) III trial.
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