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A new endoscopic method of measuring the cross-sectional area of a subglottic stenosis is presented. The method was tested against existing techniques using a model. By standardizing the distance from the objective of the endoscope to the stenotic area we were able to measure the cross-sectional area using a graduated grid held against the video screen. This technique was then compared with the standard one of estimating the diameter of a stenosis from the external diameter of the bronchoscope which can be passed through the stenosis. The methods were found to be equally accurate in measuring the lumen diameter. However, when measuring the minimum cross-sectional area, three of five observers were significantly better (P less than 0.01) using the photometric method rather than the standard method (Wilcoxon's rank sum test for paired data). The photometric technique of measuring the cross-sectional area of the subglottis is easily performed, non-traumatic, and allows a visual record to be kept.  相似文献   
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Human C-reactive protein (CRP), the classic acute phase plasma protein, increases in concentration after myocardial infarction and stroke. Human CRP binds to ligands exposed in damaged tissue and can then activate complement and its proinflammatory functions. In contrast, rat CRP, which binds to similar ligands, does not activate complement. In the present study, systemic complement depletion with cobra venom factor in adult rats subjected to middle cerebral artery occlusion did not affect cerebral infarct size, indicating that circulating complement does not contribute to injury in this model. However, we have previously reported that administration of human CRP to rats undergoing coronary artery ligation caused a marked increase in size of the resulting myocardial infarction, associated with codeposition of human CRP and rat complement in the infarcts. In the present study, we show that adult rats subjected to middle cerebral artery occlusion and then treated with human CRP similarly developed significantly larger cerebral infarcts compared with control subjects receiving human serum albumin. Human CRP can thus contribute to ischemic tissue damage in the brain as well as in the heart, and inhibition of CRP binding may therefore be a promising target for tissue protective acute therapeutic intervention in stroke as well as in myocardial infarction.  相似文献   
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Stenosis of the hypopharyngo-oesophageal junction can be a rare complication of laryngectomy and/or partial pharyngectomy and makes the insertion of voice prosthesis extremely difficult. This study describes the authors’ experiences gained by endoscopic balloon-catheter dilatation of hypopharyngo-oesophageal stenoses prior to implantation of voice prostheses in four cases. In two patients a single balloon-catheter dilatation resulted in wide enough pharyngo-oesophageal lumen on the long run. The average prosthesis wearing-times were 6.8 months in case 1 and 4.6 months in case 2, corresponding to the published literature data. In case 3, repeated dilatation of the pharyngo-oesophageal transition had proved to be unsuccessful despite taking every effort with the endoscopic balloon-catheter method. Having excised the stenotic segment, reconstruction with pectoralis major myocutaneous flap (PMMF) was indicated. Eighteen months later, a repeated restenosis was observed and a free jejunal flap needed to be performed as a final solution. In case 4, the insertion was carried out into a previously dilated jejunal free flap, which became gradually ischemic and stenotic since the major head-and neck procedure was carried out that resulted in prosthesis rejection after just 1 week. The authors emphasize that correct indication of pedicled and free flaps in head and neck reconstruction is a prerequisite from the aspect of prevention of pharyngo-oesophageal strictures. Endoscopic balloon-catheter dilatation is a safe and established method for dilatating hypopharyngo-oesophageal stenoses of different origin. The procedure provides maximum patient benefit with minimal trauma and morbidity; moreover, facilitates insertion of voice prostheses. However, a single balloon-catheter dilatation cannot always result in wide enough oesophageal lumen on the long run (case 3). Insertion of a voice prosthesis into a previously dilated ischemic jejunal segment is challenging and avoidable due to risks of complications.  相似文献   
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Epiploic appendagitis and omental infarction: pitfalls and look-alikes   总被引:3,自引:0,他引:3  
Epiploic appendagitis and omental infarction are benign self-limiting conditions that are more frequent than generally assumed. Both disorders frequently mimic symptoms of an abdominal surgical emergency, often leading to clinical misdiagnosis of appendicitis or diverticulitis. Because a misdiagnosis can result in an unnecessary laparotomy, a correct diagnosis is of great importance. Ultrasound and computed tomography can be used to make a reliable diagnosis. This pictorial essay illustrates the various ultrasonographic and computed tomographic appearances of epiploic appendagitis and omental infarction and focuses on their radiologic differential diagnoses and pitfalls. Received: 22 February 2001/Accepted: 18 April 2001  相似文献   
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OBJECTIVE: Female athletes who are at increased risk for anterior cruciate ligament (ACL) injury demonstrate biomechanical differences between limbs during athletic tasks that may persist following anterior cruciate ligament reconstruction (ACLR). This may limit an athlete's potential for safe return to sports competition. The purpose of this study was to determine if female athletes demonstrate lower limb asymmetries in landing and takeoff force following ACLR and clearance for return to competitive sports participation. We hypothesized that females following ACLR would demonstrate side-to-side differences in landing and jumping kinetics after their return to sport (2+ years) that would not be observed in a group of healthy female controls. DESIGN: Case control study. SETTING: The Sports Medicine Biodynamics Center at Cincinnati Children's Hospital Medical Center. PATIENTS: Fourteen female athletes at a mean of 27 months following ACLR and 18 healthy female athletes participated in the study. ASSESSMENT: All subjects executed a drop vertical jump (DVJ) task onto 2 force plates. Vertical ground reaction force (VGRF) was measured during landing and takeoff and was used to calculate landing phase loading rates. A 2-way analysis of variance was used to determine differences between the involved, uninvolved, and control limbs. RESULTS: Females who had undergone ACLR demonstrated increased VGRF (P = 0.001) and loading rate (P < 0.001) on the uninvolved limb during landing when compared with the involved limb and the control group. During takeoff, the involved limb showed significantly less ability to generate force (P = 0.03) than the uninvolved limb and the control limbs. CONCLUSIONS: Female athletes who have undergone ACLR and returned to sport may continue to demonstrate biomechanical limb asymmetries 2 years or more after reconstruction that can be identified during landing.  相似文献   
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Ohne Zusammenfassung  相似文献   
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