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HJ Epple FW Kirstein C Bojarski J Frege M Fromm EO Riecken JD Schulzke 《Canadian Metallurgical Quarterly》1997,32(4):308-314
Obliterative or constrictive bronchiolitis is characterized by narrowing of the small airways, due to submucosal and peribronchiolar fibrosis, with chronic obstruction. The vast majority of cases of bronchiolitis obliterans are associated with other diseases and only few cases are idiopathic. We report on the main computed tomography (CT) methods used study obliterative bronchiolitis, the CT findings and the differential diagnosis with other diseases. The dynamic study of alveolar ventilation with CT uses inspiratory and expiratory CT or high-resolution CT (HRCT), spiral dynamic CT or HRCT with advanced image display, ultrafast CT. In abnormal cases HRCT shows direct and indirect signs of small airways disease. The most common (> 80%) sign of obliterative bronchiolitis is the so-called mosaic oligohemia, with low attenuating lobules, caused by air trapping and best seen on expiratory CT, associated with blood flow redistribution to more normal lobules; this finding simulates the ground-glass pattern from infiltrative lung disease. Differential diagnosis is more difficult in the presence of true ground-glass patterns associated with diffuse bronchiolar obstruction and also with mosaic oligohemia due to pulmonary vascular disease and pulmonary emphysema. HRCT can distinguish these diseases and dynamic CT is more sensitive than functional tests in detecting regional abnormalities and air trapping. The combination of HRCT, rapid volumetric scanning and advanced image display is a powerful tool study the normal and abnormal features of bronchiolar function and alveolar ventilation. 相似文献
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W Astfalk FM H?cker HJ Kirschner G Stuhldreier P Schweizer 《Canadian Metallurgical Quarterly》1997,122(10):898-900
Since 1990, we have been conducting ambulatory pediatric surgery in an unit established solely for this purpose, supported by a team of kindergarten teachers, pediatric nurses, anesthesiologists and pediatric surgeons. This prospective investigation includes all ambulatory pediatric operations performed in our department from 1990 to 1995. In this time 3665 infants and children between the ages of 6 weeks and 18 years underwent an ambulatory operation. The ratio male to female was 4.1 to 1. The series consists of 1400 inguinal hernias, 722 inguinal testes, 191 hydroceles/funiculoceles, 75 umbilical hernias, 667 phimoses, 70 meatotomies, 59 hemangiomas, 217 endoscopies and 264 other surgical procedures. Postoperative complications defined as secondary hemorrhage, fever, obvious vomiting, urine retention and laryngospasm upon terminating anesthesia accompanied by subsequent vomiting occurred in 59 (1.6%) of all infants and children. Wound infections were seen in 0.48% (17/3517) of all patients. The recurrence rate for inguinal hernias were 0.79% and 1.12% for inguinal testes. Our experience enables us to summarize that a variety of pediatric operations can be performed today as ambulatory procedures. Nevertheless one must be prepared for the occurrence of complications and always have capacities free for inpatient care where adequate observation and treatment are available. Further improvement is necessary in quality management. In the last 20 years only a few data have been published about recurrence rates after pediatric ambulatory operations for inguinal hernias and inguinal testes. Therefore we started a prospective long- term study. 相似文献
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R Germann M Haisjackl B Schwarz N Salak E Deusch W Pajk HJ Wolf B Riedmann W Hasibeder 《Canadian Metallurgical Quarterly》1997,79(3):357-362
Haemorrhage is associated with intestinal mucosal hypoxia and impaired gut barrier function. Dopamine increases oxygen delivery to the intestinal mucosa and may thus counteract haemorrhage-induced mucosal hypoxia. Jejunal mucosal tissue oxygen tension (mucosal PO2) and jejunal oxygen saturation of mucosal microvascular haemoglobin (mucosal HbO2) were measured in 14 anaesthetized pigs. Seven animals served as controls (group C) and seven received continuous infusion of dopamine 16 micrograms kg-1 min-1 (group D) while 45% of blood volume was removed in three equal increments. Resuscitation was performed using shed blood and fluid. Mean arterial pressure and systemic oxygen delivery decreasing significantly during haemorrhage and returned to baseline after resuscitation in both groups. Mucosal PO2 decreased from 4.4 to 1.7 kPa after haemorrhage (P < 0.01) and further to 1.5 kPa after resuscitation (P < 0.01) in group C whereas group D showed an increase from 3.9 to 5.9 kPa after the start of the dopamine infusion (P < 0.05), but no significant difference from baseline after haemorrhage (2.3 kPa) (ns) or resuscitation (3.1 kPa) (ns). Mucosal HbO2 decreased from 52 to 32% after haemorrhage (P < 0.05) and increased to near baseline (37%) (ns) after resuscitation in group C whereas group D showed no significant changes from baseline (54%) throughout the experiment. Comparison between groups showed higher mucosal PO2 and HbO2 values for group D animals after the start of the dopamine infusion (P < 0.05 each), after the first two steps of haemorrhage (P < 0.01 each) and after resuscitation (P < 0.05 each). We conclude that i.v. dopamine 16 micrograms kg-1 min-1 improved tissue oxygenation of the small intestinal mucosa during moderate haemorrhage and subsequent resuscitation. 相似文献
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There are three selenium-containing proteins in human plasma: glutathione peroxidase (GSH-Px-P), albumin and selenoprotein Ph, the human analogue to selenoprotein P from rat plasma. Selenoprotein Ph was separated from the two other selenium-containing proteins by Heparin Sepharose chromatography and was shown to have about 60-70% of the total plasma selenium, while both GSH-Px-P and albumin contain about 15%. A 2588-fold purification from human plasma was achieved by using a four-step procedure. SDS-PAGE of the purified selenoprotein revealed, besides one contaminant selenium-free protein band at about 70 kDa, one selenium-containing band ranging from 54 to 67 kDa with a maximum at 63 kDa. This microheterogeneity, also recognized by IEF, may be due to the glycprotein nature of the selenoprotein Ph. The determination of the molecular mass of the native protein varied from 65 kDa using gel filtration on Fraktogel HW 55 to 89 kDa on Sephacryl S-200 HR, suggesting an interaction between the gel-matrices and selenoprotein Ph. 相似文献