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Digestive Diseases and Sciences - To determine whether the presence of portal vein thrombosis (PVT) where venous flow within the liver may be altered may delay the diagnosis of HCC and be...  相似文献   
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An assessment of a non-invasive technique for measurement of stroke distance was made using a portable Doppler ultrasound machine. The aim was to determine the measurement error of repeated stroke distance measurements (Within-observer variability) and to assess measurement agreement between two operators (between-observer variability). The measurement error (within-observer variability) for both operators was similar at approximately 2 cm. However, the measurements of the two operators (between-observer variability) did not agree well. Using the mean (SD) of three readings by each operator, the mean difference between the operators was -0.21 cm (1.96) giving a 95% confidence interval for the differences of -4.0 to +3.6 cm. There were significant positive and negative correlations between stroke distance and a variety of variables (age, height, weight, heart rate), but the relations were weak. The results indicate that the Doppler ultrasound technique for measurement of stroke distance would best be used to study trend changes in an individual patient, or subject, by a single operator.  相似文献   
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Moen AEF*, Tannæs TM, Leegaard TM. USA300 methicillin‐resistant Staphylococcus aureus (MRSA) in Norway. Community‐associated methicillin‐resistant S. aureus USA300 is known for its ability to disseminate and colonize and the clone has been detected globally. We studied the most populated area in Norway in search for the strain and for signs of endemic establishment. Strain typing techniques such as spa‐, SCCmec‐ and dru‐typing, pulsed‐field gel electrophoresis and detection of USA300 molecular markers, lukS/F‐PV and arcA, were performed. USA300 has been present in the study area since 2003 and has increased in incidence in parallel with the total MRSA incidence. Most USA300 isolates were found in the community, but isolates were also detected in health care institutions.  相似文献   
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Stroke volume is a key determinate of cardiac output. It is affected by the preload, contractility and afterload of the myocardium. It is possible to gain insight into the right and left ventricular preload following the insertion of a central venous catheter and pulmonary artery catheter to measure central venous pressure and pulmonary capillary wedge pressure, respectively. Abnormal measurements can indicate a pathophysiological state and guide management.  相似文献   
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Background

Real-time cardiovascular magnetic resonance (CMR) assessment of ventricular volumes and function enables data acquisition during free-breathing. The requirement for high spatiotemporal resolution in children necessitates the use of highly accelerated imaging techniques.

Methods

A novel real-time balanced steady state free precession (bSSFP) spiral sequence reconstructed using Compressed Sensing (CS) was prospectively validated against the breath-hold clinical standard for assessment of ventricular volumes in 60 children with congenital heart disease. Qualitative image scoring, quantitative image quality, as well as evaluation of biventricular volumes was performed. Standard BH and real-time measures were compared using the paired t-test and agreement for volumetric measures were evaluated using Bland Altman analysis.

Results

Acquisition time for the entire short axis stack (~?13 slices) using the spiral real-time technique was ~?20 s, compared to ~?348 s for the standard breath hold technique. Qualitative scores reflected more residual aliasing artefact (p?<?0.001) and lower edge definition (p?<?0.001) in spiral real-time images than standard breath hold images, with lower quantitative edge sharpness and estimates of image contrast (p?<?0.001).There was a small but statistically significant (p?<?0.05) overestimation of left ventricular (LV) end-systolic volume (1.0?±?3.5 mL), and underestimation of LV end-diastolic volume (??1.7?±?4.6 mL), LV stroke volume (??2.6?±?4.8 mL) and LV ejection fraction (??1.5?±?3.0%) using the real-time technique. We also observed a small underestimation of right ventricular stroke volume (??1.8?±?4.9 mL) and ejection fraction (??1.4?±?3.7%) using the real-time imaging technique. No difference in inter-observer or intra-observer variability were observed between the BH and real-time sequences.

Conclusions

Real-time bSSFP imaging using spiral trajectories combined with a compressed sensing reconstruction showed good agreement for quantification of biventricular metrics in children with heart disease, despite slightly lower image quality. This technique holds the potential for free breathing data acquisition, with significantly shorter scan times in children.
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Objective

This study examined if ongoing support delivered by telephone following pulmonary rehabilitation (PR) assisted chronic obstructive pulmonary disease (COPD) patients to maintain health outcomes.

Methods

Phase one (n = 79) compared post-rehabilitation telephone-based support delivered by peers compared to usual care (UC). The second phase (n = 168) compared post-rehabilitation support from peer educators, respiratory therapists (RT), or UC. Primary outcome variables were St. George's Respiratory Questionnaire (SGRQ) total score and the six minute walk test (6MWT). Measures were obtained at baseline, immediately following PR, and six-months post PR.

Results

Six-month follow-up data for phase one was collected for 66 COPD patients (n = 35 peer support, n = 31 UC) and 142 for phase two (n = 42 peer support, n = 52 RT support, n = 48 UC). Per-protocol and intention to treat (ITT) analysis in both phases found no significant group by time differences for SGRQ or 6MWT.

Conclusion

Providing peer or RT support via telephone following PR was not more effective than UC for maintaining health outcomes.

Practice implications

There are concerns with using peers to provide ongoing support to COPD patients. Additionally, COPD patients require a higher level of care than telephone support can provide.  相似文献   
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Super-resistant Plasmodium falciparum threatens the effectiveness of sulfadoxine–pyrimethamine in intermittent preventive treatment for malaria during pregnancy. It is characterized by the A581G Pfdhps mutation on a background of the double-mutant Pfdhps and the triple-mutant Pfdhfr. Using samples collected during 2004–2008, we investigated the evolutionary origin of the A581G mutation by characterizing microsatellite diversity flanking Pfdhps triple-mutant (437G+540E+581G) alleles from 3 locations in eastern Africa and comparing it with double-mutant (437G+540E) alleles from the same area. In Ethiopia, both alleles derived from 1 lineage that was distinct from those in Uganda and Tanzania. Uganda and Tanzania triple mutants derived from the previously characterized southeastern Africa double-mutant lineage. The A581G mutation has occurred multiple times on local Pfdhps double-mutant backgrounds; however, a novel microsatellite allele incorporated into the Tanzania lineage since 2004 illustrates the local expansion of emergent triple-mutant lineages.  相似文献   
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