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991.
A 40-year experience consisting of 91 cases of acute slipped capital femoral epiphysis (SCFE) was reviewed to assess the safety of manipulative reduction and to determine whether urgent reduction has an effect on the development of avascular necrosis (AVN) of the capital femoral epiphysis. All patients had a history of sudden onset of severe hip pain and were documented to have an unstable (acute) slipped epiphysis. Treatment modalities included manipulative reduction under general anesthesia followed by internal fixation (41 hips), epiphysiodesis and internal fixation (15 hips), epiphysiodesis and cast immobilization (31 hips), and cast immobilization alone (three hips). One case was treated with cast immobilization after reduction by skeletal traction. Patient follow-up averaged 44 months, and ranged from 12 to 216 months. Radiographic review identified 13 (14%) cases of AVN in the series of 91 hips. Of 42 hips reduced in <24 h from presentation, AVN developed in three (7%). Of 49 hips reduced in >24 h from presentation, AVN developed in 10 (20%). Manipulative reduction of the acute SCFE may be accomplished without increased risk of AVN. Time to reduction may be an important risk factor for development of AVN after acute SCFE. 相似文献
992.
ES Rivera TR Kimball WW Bailey SA Witt PR Khoury SR Daniels 《Canadian Metallurgical Quarterly》1998,32(3):766-772
OBJECTIVES: This study sought to evaluate the effects of veno-venous ultrafiltration on myocardial contractility in children undergoing cardiopulmonary bypass (CPB) for repair of congenital heart defects. BACKGROUND: Ultrafiltration (UF) is currently used to diminish postoperative fluid accumulation following CPB in children. Previous reports indicate improvement in hemodynamics immediately after UF, but the mechanism of its action is unknown. METHODS: Twenty-three patients (ages 2 months to 9.1 years; 13 males, 10 females) underwent UF for 10 min after CPB. Twelve patients underwent UF immediately after CPB (Group A). They were studied: (1) before and (2) after CPB, (3) after UF, and (4) 10 min after UF. Eleven patients underwent UF 10 min after CPB (Group B). They were studied: (1) before and (2) after CPB, (3) after a 10-min delay before UF, and (4) after UF. Contractility was determined by the difference in the observed and predicted velocity of circumferential fiber shortening for the measured wall stress, using transesophageal echocardiography. Left ventricular wall thickness was also measured. RESULTS: There was significant improvement in contractility after UF in both groups (mean+/-SD, Group A: -0.28+/-0.13 to -0.01+/-0.21 circ/s, p < 0.05; Group B: -0.26+/-0.16 to -0.11+/-0.17 circ/s, p < 0.05). Myocardial thickness to cavity dimension decreased in both groups following UF (Group A: 0.19+/-0.04 to 0.14+/-0.03, p < 0.05; Group B: 0.18+/-0.04 to 0.14+/-0.03, p < 0.05). CONCLUSIONS: UF improves hemodynamics by improving contractility and possibly by reducing myocardial edema in children following cardiac surgery. Enhanced patient outcome after ultrafiltration may in part be due to these changes. 相似文献
993.
Superficial angiomyxomas are rare, benign, dermal and subcutaneous tumours. We describe a 12-year-old girl who presented with a nodular swelling in the midline of her scalp that had been present since birth. Histological examination revealed an ill-defined myxoid lesion within the dermis, comprising spindle cells, blood vessels and occasional multi-nucleate giant cells. Immunohistochemical staining was negative for S-100, cytokeratin and smooth muscle actin, but focally positive for CD34. Our patient is unusual in that the angiomyxoma was present at birth, which has not previously been described. The importance of screening patients with cutaneous myxomas for cardiac lesions is discussed. 相似文献
994.
995.
LK Dalla Vecchia JL Grosfeld KW West FJ Rescorla LR Scherer SA Engum 《Canadian Metallurgical Quarterly》1998,133(5):490-6; discussion 496-7
OBJECTIVE: To evaluate the causes, clinical presentation, diagnosis, operative management, postoperative care, and outcome in infants with intestinal atresia. DESIGN: Retrospective case series. SETTING: Pediatric tertiary care teaching hospital. PATIENTS: A population-based sample of 277 neonates with intestinal atresia and stenosis treated from July 1, 1972, through April 30, 1997. The level of obstruction was duodenal in 138 infants, jejunoileal in 128, and colonic in 21. Of the 277 neonates, 10 had obstruction in more than 1 site. Duodenal atresia was associated with prematurity (46%), maternal polyhydramnios (33%), Down syndrome (24%), annular pancreas (33%), and malrotation (28%). Jejunoileal atresia was associated with intrauterine volvulus, (27%), gastroschisis (16%), and meconium ileus (11.7%). INTERVENTIONS: Patients with duodenal obstruction were treated by duodenoduodenostomy in 119 (86%), of 138 patients duodenotomy with web excision in 9 (7%), and duodenojejunostomy in 7 (5%) A duodenostomy tube was placed in 3 critically ill neonates. Patients with jejunoileal atresia were treated with resection in 97 (76%) of 128 patients (anastomosis, 45 [46%]; tapering enteroplasty, 23 [24%]; or temporary ostomy, 29 [30%]), ostomy alone in 25 (20%), web excision in 5 (4%), and the Bianchi procedure in 1 (0.8%). Patients with colon atresia were managed with initial ostomy and delayed anastomosis in 18 (86%) of 21 patients and resection with primary anastomosis in 3 (14%). Short-bowel syndrome was noted in 32 neonates. MAIN OUTCOME MEASURES: Morbidity and early and late mortality. RESULTS: Operative mortality for neonates with duodenal atresia was 4%, with jejunoileal atresia, 0.8%, and with colonic atresia, 0%. The long-term survival rate for children with duodenal atresia was 86%; with jejunoileal atresia, 84%; and with colon atresia, 100%. The Bianchi procedure (1 patient, 0.8%) and growth hormone, glutamine, and modified diet (4 patients, 1%) reduced total parenteral nutrition dependence. CONCLUSIONS: Cardiac anomalies (with duodenal atresia) and ultrashort-bowel syndrome (<40 cm) requiring long-term total parenteral nutrition, which can be complicated by liver disease (with jejunoileal atresia), are the major causes of morbidity and mortality in these patients. Use of growth factors to enhance adaptation and advances in small bowel transplantation may improve long-term outcomes. 相似文献
996.
997.
998.
PJ Johansson M J?nsson K Ahlfors SA Ivarsson L Svanberg C Guthenberg 《Canadian Metallurgical Quarterly》1997,29(5):465-468
OBJECTIVE: External reference points, particularly Kirschner pins (K-wire), placed in the region of the nasion have been shown to improve the accuracy of maxillary vertical repositioning. Although no complications associated with this technique have been reported, there is a potential for injury to the anterior cranial fossa or frontal sinus. The purpose of this study was to measure the shortest distance from the nasion to the anterior cranial fossa and from the nasion to the frontal sinus. These measurements were used to establish anatomic guidelines governing safe placement of external reference point pins. STUDY DESIGN: Twenty-seven cadaver heads were sectioned in the midsagittal plane for gross study. Using a Boley gauge, two specific measures were obtained: (1) distance from deepest depression of nasion to the most anterior and inferior projection of the anterior cranial fossa, and (2) distance from nasion to the most inferior aspect of the frontal sinus. All measurements were made in the midsagittal plane. RESULTS: The average distance from nasion to anterior cranial fossa was 16.9 mm (range 13.0 to 20.0 mm) and the smallest distance, 13.0 mm, was seen in two specimens. The average distance from nasion to the frontal sinus was 6.2 mm (range 2.0 to 10.0 mm) and the smallest distance, 2.0 mm, was seen in three specimens. CONCLUSION: Based on our findings, we recommend the following: (1) place pin to a depth of no more than 8 mm into bone, (2) place pin 5 to 10 mm inferior to soft tissue nasion, and (3) place pin in an anterosuperior to posteroinferior direction (i.e., roughly perpendicular to the nasal dorsum). When these anatomic guidelines are followed, one would expect minimal morbidity associated with the placement of ERP pins. 相似文献
999.
Changes in the heat-induced gelation properties of reconstituted rabbit skeletal actomyosin stored under a high salt concentration at pH 6.0 and 0 degree C were investigated at different weight ratios of actin to myosin by using dynamic rheological and biochemical measurements. The addition of actin resulted in a pronounced peak maximum at about 50 degrees C and an accompanying temporary reduction in the range at about 50 degrees C to 60 degrees C. The more the initial actin concentration was increased, the greater was the area of the peak/shoulder. However, this area was markedly diminished with increasing storage time. As a result, the dynamic rheological pattern was transformed from an actomyosin type into a myosin type. The relationship between the G' value at 80 degrees C and the actin/myosin weight ratio was curvilinear, with a peak at the ratio of 0.05, immediately after storage was started. This profile changed during storage, depending on the extent to denaturation of actin and myosin in the reconstituted actomyosin (RAM). The G' value of actomyosin in 0.5 M KCl with a small actin/myosin ratio of 0.05 decreased to one-half of its initial value after 7 days of storage, whereas the G' value with a large actin/myosin ratio of 0.225 increased by about 1.6 times. In 1.5 M KCl, all the G' values declined to the level with myosin alone after 7 days of storage. The time-course plots of the remaining actin concentration in RAM at different weight ratios of actin to myosin after being treated with 0.5 M or 1.5 M KCl showed a decrease in the actin content with increasing storage time, and an increase in the KCl concentration to 1.5 M KCl promoted the denaturation of actin in RAM faster than with 0.5 M KCl. The surface hydrophobicity of each RAM sample progressively increased with increasing storage time, while little significant increase in the sulfhydryl (SH) content during storage was observed. It is concluded that changes in the heat-induced gelation properties of actomyosin during storage are largely attributable to the denaturation of actin rather than to the denaturation of myosin or to quantitative changes in the SH content and hydrophobicity. 相似文献
1000.
ML Freeman SA Huntley MJ Meredith GA Senisterra J Lepock 《Canadian Metallurgical Quarterly》1997,2(3):191-198
There is an increasing realization that every effort should be made to minimize the exposure to ionizing radiation of patients and members of the dental team. There are, however, few published guidelines to assist the general practitioner in deciding whether or not radiographs are needed. There is even less information concerning the taking of dental radiographs of children. Using the Delphi Technique this study set out to seek a consensus amongst Consultant Paediatric Dentists (n = 36) working in the UK as to when dental radiographs should and should not be taken of children cared for within general dental services. A two-stage questionnaire was used and a response of 94% and 76% was obtained in the first and second questionnaire respectively. A consensus view was reached regarding whether or not radiographs should be taken in a series of 17 specific clinical situations. 相似文献