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排序方式: 共有420条查询结果,搜索用时 31 毫秒
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Complications of automatic implantable cardioverter defibrillators: radiographic, CT, and echocardiographic evaluation 总被引:1,自引:0,他引:1
Goodman LR; Almassi GH; Troup PJ; Gurney JW; Veseth-Rogers J; Chapman PD; Wetherbee JN 《Radiology》1989,170(2):447-452
Automatic implantable cardioverter defibrillators (AICDs) were studied in three groups: (a) Serial radiographs were reviewed in 51 clinic patients. Twenty of 96 (21%) AICD patches distorted with time. (b) Thirty-six postoperative computed tomographic (CT) scans of asymptomatic patients revealed that pericardial fluid collections were frequent during the month after surgery but rare beyond that. Echocardiography was insensitive for these collections. CT also demonstrated dense fibrosis around some distorted patches, months after surgery. (c) Five other patients with pericardial infection had distorted patches, and the four studied with CT had fluid beneath their patches. (d) A case of constrictive pericarditis had distorted patches but was not diagnosed with CT. The authors conclude that distorted patches may indicate postoperative complications and that CT is the imaging modality of choice. 相似文献
94.
Platelet membrane microparticles in blood bank fresh frozen plasma and cryoprecipitate 总被引:4,自引:0,他引:4
Cryoprecipitate has been demonstrated to correct the bleeding abnormality of patients with some congenital (storage pool disease) and acquired (uremia) platelet abnormalities, but the reason for this effect is unknown. We found significant platelet contamination in plasma harvested to prepare fresh frozen plasma and cryoprecipitate. The platelet membrane microparticles produced by freezing and thawing of the plasma were highly concentrated in cryoprecipitate and may contribute to its therapeutic effect. 相似文献
95.
A prospective study on the value of ultrasound (US) for the staging of 70 cases of cancer of the tongue and tonsil was performed. A real-time, high-frequency transducer was used, and the examination was often coupled with endobuccal palpation. US did not visualize the tumor in nine of 42 cases of tongue cancer (seven stage T1 and two anterior stage T2 tumors); US accurately defined tumor size in 33 cases. The degree of in-depth extension and the location with respect to the median line (only four false results) were evaluated correctly. With regard to 28 tonsil cancers, US depicted extension from the tonsillar fossa to the tongue in all cases but one (13 of 14 cases). US is valuable for the detection of cervical lymph nodes associated with both tongue and tonsil tumors and is a safe and helpful technique for the follow-up of medium-size lesions. The major limitations of US include the nonvisualization of superficial lesions, reduced accuracy for evaluation of the extension of large tumors, and analysis of posterior pharyngeal extension. 相似文献
96.
Rebreathing of expired air may be a lethal hazard for prone sleeping infants. This paper describes a mechanical model to simulate infant breathing, and examines the effects of bedding on exhaled air retention. Under simulated rebreathing conditions, the model allows the monitoring of raised carbon dioxide (CO2) inside an artificial lung-trachea system. Resulting levels of CO2 (although probably exaggerated in the mechanical model compared with an infant, due to the model's fixed breathing rate and volume) suggest that common bedding materials vary widely in inherent rebreathing potential. In face down tests, maximum airway CO2 ranged from less than 5% on sheets and waterproof mattresses to over 25% on sheepskins, bean bag cushions, and some pillows and comforters. Concentrations of CO2 decreased with increasing head angle of the doll, away from the face down position. Recreations of 29 infant death scenes also showed large CO2 increases on some bedding materials, suggesting these infants could have died while rebreathing. 相似文献
97.
Complicated cholesteatomas: CT findings in inner ear complications of middle ear cholesteatomas 总被引:1,自引:0,他引:1
Patients with facial palsy and middle ear disease, which may be chronic but clinically occult, may have a cholesteatoma with extension medially along the facial canal. In two patients, axial computed tomographic (CT) scans demonstrated involvement of the medial petrous bone. Patients with vertigo and chronic middle ear disease may have a cholesteatoma with a "fistula" between the middle and inner ears. Although the fistula usually involves the lateral semicircular canal, the cholesteatoma may pass through the oval window. In two patients, coronal CT scans showed extension to the oval window in one and through it in the other. 相似文献
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标题 Carvedilol对慢性心力衰竭患者病残率和病死率的影响作者 PackerM,BristowMR,CohnJN,等 NEnglJMed,1996,334:1349~1355 研究疾病:充血性心力衰竭。目的:Carvedilol是一种非选择性β受体阻滞剂,它不但具有α1受体阻滞作用,而且具有抗氧化特性。本研究旨在对其对慢性心力衰竭患者存活和住院的影响进行评估。 设计:随机、双盲、安慰剂对照的多中心研究。病人资料:共1094名心力衰竭患者,起病时间≥3月,虽已用利尿剂和ACEI制剂治疗… 相似文献
100.
Jakeline Rheinheimer Patrícia Klarmann Ziegelmann Rodrigo Carlessi Luciana Ross Reck Andrea Carla Bauer Cristiane Bauermann Leit?o Daisy Crispim 《Islets》2014,6(4)
Collagenases are critical reagents determining yield and quality of isolated human pancreatic islets and may affect islet transplantation outcome. Some islet transplantation centers have compared 2 or more collagenase blends; however, the results regarding differences in quantity and quality of islets are conflicting. Thus, for the first time, a mixed treatment comparison (MTC) meta-analysis was carried out to compile data about the effect of different collagenases used for human pancreas digestion on islet yield, purity, viability and stimulation index (SI). Pubmed, Embase and Cochrane libraries were searched. Of 755 articles retrieved, a total of 15 articles fulfilled the eligibility criteria and were included in the MTC meta-analysis. Our results revealed that Vitacyte and Liberase MTF were associated with a small increase in islet yield (islet equivalent number/g pancreas) when compared with Sevac enzyme [standardized mean difference (95% credible interval – CrI) = −2.19 (−4.25 to −0.21) and −2.28 (−4.49 to −0.23), respectively]. However, all other enzyme comparisons did not show any significant difference regarding islet yield. Purity and viability percentages were not significantly different among any of the analyzed digestion enzymes. Interestingly, Vitacyte and Serva NB1 were associated with increased SI when compared with Liberase MTF enzyme [unstandardized weighted mean difference (95% CrI) = −1.69 (−2.87 to −0.51) and −1.07 (−1.79 to −0.39), respectively]. In conclusion, our MTC meta-analysis suggests that the digestion enzymes currently being used for islet isolation works with similar efficiency regarding islet yield, purity and viability; however, Vitacyte and Serva NB1 enzymes seem to be associated with an improved SI as compared with Liberase MTF. 相似文献