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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.
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   
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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   
5.
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   
6.
Ten thrombocytopenic patients (platelets < 10–24 × 10(9)/L) who were refractory to platelet transfusion were investigated for their responsiveness to staphylococcal protein A column therapy. Nine patients had previously been treated with steroids, intravenous immune globulin, and/or other forms of immunosuppressive therapy without improvement in their transfusion response. All patients were receiving multiple platelet transfusions without achieving 1-hour corrected count increments (CCIs) > or = 7500. Eight patients had antibodies that reacted with platelets and were directed against HLA class I antigens, ABO antigens, and/or platelet-specific alloantigens. Plasma (500-2000 mL) from each patient was passed over a protein A silica gel column and then returned to the patient. Patients received from 1 to 14 treatments. A positive response to protein A therapy was defined as at least a doubling of the pretreatment platelet count and/or two successive 10- to 120-minute posttransfusion CCIs > or = 7500. Following plasma treatments, 6 of 10 patients responded with daily platelet counts that averaged 48 +/− 11 × 10(9) per L as compared with counts of 16 +/− 7 × 10(9) per L (p < 0.0005) before treatment. Posttransfusion CCI values determined in four of these patients averaged 2480 +/− 810 and 10,010 +/− 3540 (p < 0.005) before and after treatment, respectively. In contrast, among the four unresponsive patients, platelet counts averaged 10 +/− 9 and 13 +/− 10 × 10(9) per L (p = NS), respectively, while posttransfusion CCIs were 700 +/− 1410 and 1520 +/− 2460 (p = NS), respectively.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
7.
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   
8.
Results of clinical, contrast enema (CE), and computed tomographic (CT) examinations in 39 patients with perforated colorectal neoplasms were retrospectively reviewed. Twenty patients were toxemic at initial presentation, but in only four patients was the diagnosis of perforated colorectal neoplasm initially suspected clinically. CE study was performed in 22 patients and enabled the diagnosis of perforated neoplasm in 11 cases, neoplasm alone in eight, and neither neoplasm nor perforation in three. CT was performed in 38 patients and enabled the diagnosis of perforated neoplasm in 36; pericolic phlegmon but no mass lesion was evident in two. In 16 patients, CT also demonstrated metastatic disease. Because of its reliability in establishing the diagnosis and staging the extent of the inflammatory and neoplastic disease, CT is indicated in cases of suspected or proved perforated colorectal neoplasm and in cases in which CE study findings are indeterminate or suggestive of perforated neoplasm.  相似文献   
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A Messineo  R M Filler  A Bahoric  C R Smith 《Journal of pediatric surgery》1992,27(8):1131-4; discussion 1134-5
Tracheoplasties with various autografts (cartilage, periosteum, pericardium) have been used in the treatment of long-segment tracheal stenosis. Previous studies have shown that cartilage allografts survive transplantation on a long-term basis in various sites of the body. In this study we set out to determine if cryopreserved cartilage and cryopreserved tracheal allografts would survive when used to cover tracheal defects in animals. A rectangular defect (2.8 +/- 0.3 cm long and incorporating 50% of tracheal circumference) was created in the thoracic trachea of 18 piglets. The defect was covered with the excised tracheal segment in 6 (group A, control group), with a cryopreserved tracheal allograft in 6 (group B), and with a cryopreserved cartilage allograft harvested from the scapula in 6 (group C). The allografts were cryopreserved, by a standard slow-freezing technique, at -80 degrees C for more than 21 days. All animals survived the grafting procedure and were killed after 2 months. None had signs of airway obstruction. Using the trachea above the defect as the standard, the mean sagittal narrowing of the airway in the repaired trachea was 0.4 mm in group A, 0.7 mm in group B, and 0.6 mm in group C; the coronal diameter in normal and grafted trachea was similar. The lumen of all grafts was lined by regenerating respiratory epithelium, and cilia were seen in many. Some cartilage was reabsorbed in group A and B but cartilage islands were present in all. In group A, reabsorption of cartilage was minimal. These findings suggest that segments of trachea or cartilage allografts can be cryopreserved, stored, and, subsequently, used when necessary for tracheoplasty.  相似文献   
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