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1.
A major problem in tracheal transplantation is the restoration of an adequate vascular supply to the transplanted trachea. In 12 piglets, a segment (6 rings) of thoracic trachea was removed and the excised segment was then sutured back in place. In 9 animals (group A), a vascularized omental flap was wrapped around the autotransplanted trachea. In the other 3 pigs (group B), the omentum was not used. Eight of 9 group A pigs were killed, 1 or 2 months later, having had no signs of airway obstruction; the 9th pig was killed after 14 days because of airway obstruction. The 3 pigs in group B were killed after 11 to 13 days because of progressive respiratory obstruction. In the 8 asymptomatic pigs in group A, the omental flap was viable and tracheal growth was normal with no differences in diameter between normal and autotransplanted trachea. Histologically intact cartilage was lined with respiratory epithelium. In the one group A pig who was killed early, the omental flap was necrotic. In this pig and in the 3 group B animals, extensive tracheal necrosis and nonviable cartilage were observed. These findings indicate that in the pig, a 6-ring segment of trachea can be transplanted with vascularization provided by an omental flap.  相似文献   
2.
Ruggieri  PM; Laub  GA; Masaryk  TJ; Modic  MT 《Radiology》1989,171(3):785-791
The technique and feasibility of magnetic resonance (MR) angiography of intracranial vessels were studied in 35 healthy volunteers. Variations in image orientation, repetition time (TR), and flip angle were evaluated to determine their effects on flow-related enhancement. Gradient modifications--including echo time (TE), motion compensation, bandwidth, and field of view--were also studied in an effort to reduce motion-induced phase shifts. Results indicated that a FISP (fast imaging with steady precession) sequence with a TR of 50 msec, TE of 15 msec, velocity compensation in the read and section-select directions, acceleration compensation in the read direction, anisotropic volume, and a 1.25-mm partition thickness produced three-dimensional angiographic MR images that were accurate and reproducible in the depiction of the major intracranial vessels. Difficulties with field of view, persistent signal void secondary to higher-order motion, and spatial resolution remain major problems requiring additional study.  相似文献   
3.
Despite widespread use of radiofrequency (RF)-shrinkage, there have been no studies on the influence of RF-energy on neural elements of collagenous tissue. The purpose of this study was to examine the effect of RF-shrinkage on neural structures of capsuloligamentous tissue and the recovery of neural elements under different postoperative treatment protocols. One patellar tendon of 46 New-Zealand-White rabbits was shrunk. Six rabbits were sacrificed immediately postoperative. Twenty rabbits were not immobilized, 10 were immobilized for 3 and 10 were immobilized for 6 weeks. A monoclonal antibody, specific against a neurofilament protein, was used to detect nerves and neural structures. Staining pattern of nerve fibres was significantly altered immediately postoperative. After 3 weeks the number of nerve fibres and bundles decreased significantly in immobilized and non-immobilized limbs. The loss of nerve fibres was significantly less in immobilized limbs. At 6 weeks the number of neural elements in immobilized limbs increased to the level of untreated control tissue. In non-immobilized limbs we found no recovery of neural elements 9 weeks postoperatively. At this time the number of nerve fibres and bundles was still significantly less compared to the untreated control limbs. RF-shrinkage causes significant alteration of neural elements. Under immobilization nerve fibres and bundles reach the level of normal untreated tissue. Careful rehabilitation is important after RF-shrinkage. Not only for biomechanical reasons, but also to allow the neural elements to recover, thermally modified tissue should be protected from normal physiologic loads.  相似文献   
4.
Paediatric dacryocystorhinostomy   总被引:1,自引:0,他引:1  
Of 258 cases of dacryocystorhinostomy performed on children in the period September 1981 to September 1991, 130 were for simple, unresolved congenital nasolacrimal duct obstruction. Other indications for surgery included punctal agenesis, lacrimal fistula, post-traumatic and post-inflammatory canalicular obstruction. Of 177 children without canalicular pathology, 171 (96%) were relieved of symptoms with one operation, without canalicular intubation. Of 81 cases with canalicular disease, 55 of 70 (79%) who underwent DCR plus canalicular intubation, and 10 of 11 who underwent DCR plus Lester-Jones tube, were substantially improved with one operation. No child required peroperative or postoperative blood transfusion. Dacryocystorhinostomy in childhood, in experienced surgical hands, is a safe procedure, achieving relief of symptoms in most cases, particularly in the absence of canalicular disease.  相似文献   
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Zusammenfassung Fragestellung Ziel der vorliegenden Untersuchung ist es, die Indikation, OP-Technik sowie die Ergebnisse des endoskopischen Releases der Plantarfaszie darzustellen. Material und Methode An 5 nicht fixierten Präparaten wurde eine biportale Technik zum endoskopischen Release der Plantarfaszie erprobt. Ziel war es hierbei zum einen, die Relation zwischen Plantarfaszie und plantarem Fersensporn zu evaluieren; zum anderen wurde eine Technik erprobt, bei welcher nur 50–70% der medialen Plantarfaszie vom Kalkaneus abgelöst wurde.Über einen Zeitraum von 5 Jahren wurde diese Technik bei 10 männlichen und 7 weiblichen Patienten mit dem klinischen Bild einer Plantarfasziitis durchgeführt. Das mittlere Alter der Patienten betrug 35 Jahre (24–56 Jahre). Alle Patienten durchliefen zunächst konservative Therapieversuche von zumindest 6 Monaten. Ergebnisse Bei den ersten 5 Patienten wurde der Eingriff unter Bildwandlerkontrolle durchgeführt; bei den weiteren Patienten erfolgte die Resektion ohne intraoperative BV-Kontrolle. Bei allen Patienten konnte der Eingriff wie geplant durchgeführt werden. Die endoskopischen Portale heilten ohne Probleme. Die OP-Zeit ist im Rahmen der Lernkurve mit Zeiten zwischen 21 und 74 Minuten (MW: 41 Minuten) noch länger als in der offenen Technik. Der Nachuntersuchungszeitraum betrug zwischen 4 und 48 Monate (MW: 18,5 Monate). Bei 13 der 17 Patienten kam es zu einer klinischen Verbesserung und sie würden den Eingriff erneut durchführen lassen. 7 Patienten zeigten ein gutes und 6 ein sehr gutes Ergebnis im Ogilvie-Harris-Score. Bei 2 Patienten war das initiale Ergebnis nicht zufriedenstellend. Die Ursache hier lag in einer ossären Übermüdungsreaktion des Kalkaneus. Diese Komplikation wurde durch Entlastung über 6 Wochen symptomastisch behandelt. Bei zwei weiteren Patienten stellten sich sekundäre Überlastungen am lateralen Fußrand ein. Im Rahmen der frühen Rehabilitationsphase war es wichtig, trotz des minimalinvasiven Vorgehens, eine vorsichtige Belastungssteigerung durchzuführen. Schlussfolgerung Die Technik des endoskopischen Releases der Plantarfaszie (ERPF) ist standardisiert und reproduzierbar durchführbar. Sie führt zu guten mittelfristigen Ergebnissen. Ein Stabilitätsverlust der plantaren Verspannung sollte jedoch unbedingt vermieden werden.  相似文献   
8.
Four groups of piglets were used to test the use of pericardium and periosteum as free grafts in the repair of full thickness cervical tracheal defects. Pericardium provided an airtight, rapidly healing graft, but did not give sufficient structural rigidity to prevent narrowing and growth failure at the graft site. Composite grafts of pericardium and periosteum were also unsatisfactory, in that the periosteum failed to produce enough bone to prevent collapse of the graft. Since previous studies have shown that periosteal grafts result in good bone formation when applied alone or as an extramucosal support, it is concluded that the osteogenic potential is dependent on the available blood supply and speed of revascularization. It appears that the presence of pericardium in the composite grafts may have inhibited this property.  相似文献   
9.
Factors influencing women to undergo screening mammography   总被引:2,自引:0,他引:2  
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10.
The APSA scientific program has indeed been a forum for progress for a broad spectrum of medical and surgical problems affecting infants and children. Significant contributions from studies at the bedside and in the laboratory have been made by an extraordinarily large percent of APSA members from both children's and general hospitals. In addition to the many advances that apply to our own specialty, fundamental advances have been recognized and accepted by others. Developments for the future have been identified and our entire membership can be proud of the wonderful achievements of the last 20 years of APSA scientific programs. Finally, I thank you all for giving me the honor to serve as the President of this outstanding organization, which has accomplished so much already, but whose best days are yet to come.  相似文献   
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