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排序方式: 共有473条查询结果,搜索用时 15 毫秒
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The present study compared the accuracy of ventilation perfusion scintigraphy (VQS) and CT pulmonary angiography (CTPA) for the diagnosis of pulmonary embolism. This was a prospective observational study of 112 patients with suspected pulmonary embolism (PE) who could be studied with both investigations within 24 h. Results were compared to final diagnosis at completion of 6-month follow up, using receiver operating characteristic (ROC) analysis. Pulmonary embolism was diagnosed in 27 referred patients (24%). The sensitivity and specificity of VQS and CTPA were similar to that reported from the literature. A normal VQ scan had the highest negative predictive value (100%), while a high-probability VQ scan had the highest positive predictive value (92%). There was no overall difference (area under the ROC curve (AUC)) between VQS (AUC (95% CI) = 0.82 (0.75,0.89)) and CTPA (AUC = 0.88 (0.81,0.94)) for the diagnosis of PE. Among patients with abnormal chest X-rays, CTPA (AUC 0.90 (0.83,0.97)) appeared somewhat better than VQS (AUC 0.78 (0.68,0.88)) but this difference did not reach statistical significance. In this instance, CTPA is at least as accurate as VQS and may provide an opportunity to make alternative diagnoses.  相似文献   
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Fornage  BD; Schernberg  FL; Rifkin  MD 《Radiology》1985,155(3):785-788
Twenty-five surgically confirmed soft-tissue lesions of the hand were examined prospectively by real-time ultrasound. Use of sonography enabled a reliable diagnosis of the cystic or solid nature of soft-tissue lesions, an accurate estimation of the volume, and precise three-dimensional localization of the abnormality. Sonography also facilitated the location of foreign bodies. Assessment of anatomic relationships of these lesions to tendons and surrounding structures by real-time sonography during palpation, flexion, and/or extension also aided in the surgical approach.  相似文献   
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Defective opsonization in multiple myeloma   总被引:1,自引:0,他引:1  
Cheson  BD; Plass  RR; Rothstein  G 《Blood》1980,55(4):602-606
The mechanisms responsible for the unusual susceptibility of multiple myeloma (MM) patients to infections are incompletely defined. Since MM is associated with decreased production of normal serum proteins, we investigated the possibility that the production of opsonins might also be impaired. The neutrophil chemiluminescence assay of opsonization was used to evaluate the ability of serum from patients with MM to opsonize zymosan. It was found that sera from 18 MM patients exerted only 50% +/- 2.5% (mean +/- SEM) of the opsonic activity found in 18 control sera (p less than 0.001). In mixture experiments, untreated normal serum completely restored the opsonic activity of MM serum, suggesting a deficiency of opsonic factors rather than an inhibitor. In other mixture experiments, heat-inactivated normal serum only partially corrected the opsonic defect in MM serum. Serum from three patients had low C3 levels, and treatment of particles with these resulted in a greater opsonic defect than the patient population as a whole (p less than 0.02). No correlation between the opsonic defect and infections was established over an 18-mo period. These data suggest that MM serum lacks both heat-stable and heat-labile opsonic activity, the direct clinical significance of which remains to be clarified. However, these studies support the concept that defective host resistance in MM may be multifactoral, combining opsonic abnormalities with other defects previously described.  相似文献   
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Chronic rejection accounts for most renal allograft losses after the first year posttransplantation. On March 24 and 25, 1997, a roundtable of five transplant surgeons, two nephrologists, and one pathologist assembled in Dallas, Texas, to review critical issues surrounding chronic renal allograft rejection. This article summarizes the presentations and relevant discussions of this meeting regarding the cause of chronic rejection, clinical diagnoses, risk factors, future prospects for intervention strategies, and general recommendations for the transplant community. Growing evidence indicates that chronic rejection is the aggregate sum of irreversible immunologic and nonimmunologic injuries to the renal graft over time. A history of acute rejection episodes and inadequate immunosuppression, likely attributable to inconsistent cyclosporine exposure or poor patient compliance, are among the most recognizable immunologic risk factors for chronic rejection. Donor organ quality, delayed graft function, and other donor and recipient variables leading to reduced nephron mass are nonimmunologic factors that contribute to the progressive deterioration of renal graft function. Clinical management of renal transplant recipients should incorporate both immunologic- and nonimmunologic-based intervention strategies aimed at minimizing risk factors to thwart the progression of chronic rejection and improve long-term allograft and patient survival.  相似文献   
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腹部外科常见感染性疾病的病原菌及药敏试验研究   总被引:1,自引:0,他引:1  
为了了解本地区本医院腹部外科感染性疾病病原菌的构成比和药物敏感率的变化,指导临床用药,我们采用美国BD公司生产的6B和7D两种增菌瓶采集标本和培养细菌,并用该公司生产的生化板和药敏板,对1994~1996年269例常见的普外科感染性疾病患者的手术标本进行前瞻性的细菌培养和药敏试验研究.  相似文献   
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Study ObjectiveTo investigate the efficiency of a double curve nasotracheal tube on lightwand-guided nasotracheal intubation.DesignProspective, randomized, controlled trial.SettingUniversity medical center hospital.Patients60 ASA physical status I and II patients undergoing oromaxillofacial surgery.Interventions and MeasurementsPatients undergoing surgery with nasotracheal intubation and general anesthesia were randomly enrolled in the laryngoscopy group or the lightwand group. The same type of double curve nasotracheal tube was used in both groups. In the laryngoscopy group, intubation was assisted with a Macintosh No. 3 standard curved blade and Magill forceps. In the lightwand group, intubation was aided with a flexible lightwand device (without the inner stiff stylet). Intubation time was divided into two parts: Part one, from selected naris to oropharynx; Part two, from oropharynx into trachea. Part one, Part two, and total intubation time, hemodynamic responses to nasotracheal intubation, and adverse events or complications were recorded.Main ResultsTotal intubation times in the lightwand group and the laryngoscopy group were 22.8 ± 8.0 sec vs 30.3 ± 8.2 sec (P < 0.001), respectively. The lightwand group had comparable hemodynamic responses to those of the laryngoscopy group. Adverse events and complications were all self-limited, with similar occurrence in both groups.ConclusionFor patients undergoing oromaxillofacial surgery, modified lightwand-guided nasotracheal intubation is feasible with a double curve nasotracheal tube and is an efficient alternative technique.  相似文献   
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