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111.
Kaufman MR Westreich R Ammar SM Amirali A Iskander A Lawson W 《Archives of facial plastic surgery》2004,6(2):94-100
OBJECTIVE: To introduce and assess a system for the delivery of fibroblast growth factor to autologous cartilage grafts using fibrin sealant and analyze whether this "enhancement" results in reduced rates of cartilage resorption and greater preservation of normal architectural features compared with "unenhanced" cartilage grafts. METHODS: Auricular cartilage segments measuring 1 cm(2) were harvested from 12 New Zealand white rabbits, morselized, and implanted into the subcutaneous dorsum of the upper back for 3 months. The conditions included (1) cartilage alone; (2) cartilage + fibrin sealant; (3/4) cartilage + acidic or basic fibroblast growth factor (aFGF or bFGF); and (5/6) cartilage + fibrin sealant + aFGF or bFGF. Subsequent to graft harvest, gross and microscopic assessments were performed to assess size, structural integrity, and architectural features, with comparisons performed between each of the conditions. RESULTS: The mean areas of the harvested cartilage grafts treated with fibrin sealant + aFGF or bFGF were 1.23 cm(2) and 1.19 cm(2), respectively, while the corresponding value for the untreated (ie, cartilage alone) specimens was 1.03 cm(2). The percentage of decrease in size was 45% for the untreated specimens and 0% for the specimens treated with fibrin sealant + aFGF or fibrin sealant + bFGF. Cartilage treated with fibrin sealant + bFGF had the greatest quantity of elastin fibers of the 6 conditions. Cartilage grafts treated with fibrin sealant alone demonstrated the most intense ground substance staining on a computerized measure of pixel intensity. CONCLUSIONS: Our findings demonstrated significant improvements in graft quality using fibroblast growth factor and fibrin sealant or even fibrin sealant alone. These findings may justify changes in how cartilage grafts are prepared and delivered for facial augmentation procedures to reduce graft resorption and maintain the structural integrity of the cartilage. Further trials will be performed to elucidate the optimal growth factor concentrations for maximum structural and architectural benefits. 相似文献
112.
Whole-spine magnetic resonance imaging in patients with neurofibromatosis type 1 and spinal deformity 总被引:3,自引:0,他引:3
Ramachandran M Tsirikos AI Lee J Saifuddin A 《Journal of spinal disorders & techniques》2004,17(6):483-491
OBJECTIVE: Whole-spine magnetic resonance imaging (MRI) has been recommended in the preoperative evaluation of patients with neurofibromatosis type 1 (NF-1). However, no large study has identified the role of MRI in the classification and management of this condition. A retrospective study of 27 patients with NF-1, presenting with spinal deformity, who were investigated with plain radiographs and whole-spine MRI, was conducted to determine the role of whole-spine MRI in the classification and management of patients with NF-1 and spinal deformity. METHODS: The medical records, radiographs, and MRI studies of 27 neurologically intact patients with NF-1 and spinal deformity, who had been followed for a minimum of 2 years, were reviewed. RESULTS: The study group comprised 27 patients, 11 of whom were categorized as having nondystrophic and 16 as having dystrophic curves based on radiographic features. All patients had normal neurologic function. In the nondystrophic group, MRI identified dystrophic changes in four patients (associated with a high rate of curve progression in one). A high incidence of intraspinal and paraspinal neurofibromas was documented (overall 37%) in both nondystrophic and dystrophic groups. Significantly more tumors were identified adjacent to the convexity of the curve in the dystrophic group. CONCLUSION: In a mixed population of pediatric and adult patients with NF-1, normal neurologic function, and spinal deformity, MRI of the whole spine proved useful in the identification of occult vertebral dysplasia and in demonstration of intraspinal and paraspinal neoplasms. 相似文献
113.
Yerys BE White DA Salorio CF McKinstry R Moinuddin A DeBaun M 《Journal of pediatric hematology/oncology》2003,25(6):495-498
Cerebral infarcts occur in approximately 30% of children with sickle cell disease (SCD), but little information exists regarding remediation of associated cognitive deficits. The authors examined the benefits of training children with infarcts to use memory strategies. Six children with SCD-related infarcts received academic tutoring; three of these children received additional training in memory strategies (silent rehearsal to facilitate short-term memory and semantic organization to facilitate long-term memory). The performance of children receiving strategy training appeared to improve more than that of children receiving only tutoring. Memory in children with SCD-related infarcts may be enhanced through strategy training. 相似文献
114.
Intracranial hemorrhage progressing to porencephaly as a result of congenitally acquired cytomegalovirus infection--an illustrative report 总被引:2,自引:0,他引:2
OBJECTIVE: To report ultrasound and magnetic resonance imaging (MRI) findings in a fetus with intracranial hemorrhage and porencephaly, presumed secondary to intrauterine cytomegalovirus (CMV) infection. METHODS: A 20-year-old, G2, P1 woman presented at 28.6 weeks' gestation after ultrasound examination demonstrated apparently isolated fetal ascites. Evaluation included maternal serology, amniocentesis, and repeated ultrasound examinations. Fetal MRI evaluation was also performed. The infant was born at 35 weeks' gestational age. RESULTS: Maternal serology was positive for CMV IgG. Intrauterine CMV infection was confirmed using polymerase chain reaction (PCR). At 31.6 weeks' gestation, ultrasound demonstrated borderline lateral cerebral ventriculomegaly. MRI of the fetal brain on the same day demonstrated parenchymal hemorrhage in the right posterior temporal and parietal regions along with mild ventricular enlargement. Sonography one day before delivery revealed brain parenchymal cystic change consistent with porencephaly of the right posterior temporal and parietal region. Postnatal ultrasound, computed tomography (CT), and MRI confirmed the diagnosis of a porencephalic cyst communicating with the posterior body of the right lateral ventricle. Placental pathology was consistent with CMV infection. CONCLUSION: This case report illustrates that fetal MRI is a useful adjunct in the evaluation of intrauterine infection with CMV. 相似文献
115.
116.
Ali A Kaur G Hamid H Abdullah T Ali M Niwa M Alam MS 《Journal of Asian natural products research》2003,5(2):137-142
Terminoside A (1), a new oleanane-type triterpene was isolated from the acetone fraction of the ethanolic extract of stem bark of Terminalia arjuna. The structure was established as olean-1alpha,3beta,22beta-triol-12-en-28-oic acid-3beta-D-glucopyranoside. On the basis of spectral data and chemical reactions, terminoside A, potently inhibited nitric oxide (NO) production and decreased inducible nitric oxide synthase (iNOS) levels in lipopolysaccharide-stimulated macrophages. 相似文献
117.
Imaging tumours of the brachial plexus 总被引:6,自引:0,他引:6
Saifuddin A 《Skeletal radiology》2003,32(7):375-387
Tumours of the brachial plexus are rare lesions and may be classified as benign or malignant. Within each of these groups, they are further subdivided into those that are neurogenic in origin (schwannoma, neurofibroma and malignant peripheral nerve sheath tumour) and those that are non-neurogenic. Careful pre-operative diagnosis and staging is essential to the successful management of these lesions. Benign neurogenic tumours are well characterized with pre-operative MRI, appearing as well-defined, oval soft-tissue masses, which are typically isointense on T1-weighted images and show the "target sign" on T2-weighted images. Differentiation between schwannoma and neurofibroma can often be made by assessing the relationship of the lesion to the nerve of origin. Many benign non-neurogenic tumours, such as lipoma and fibromatosis, are also well characterized by MRI. This article reviews the imaging features of brachial plexus tumours, with particular emphasis on the value of MRI in differential diagnosis. 相似文献
118.
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120.
Naseer A Saeed W 《Journal of the College of Physicians and Surgeons--Pakistan : JCPSP》2003,13(2):108-110
A case of asymptomatic 60 years old male diagnosed as Non-Hodgkin's lymphoma (angioimmunoblastic T-cell type) invading thoracic duct leading to chylothorax is presented. Generally, patients with this moderately aggressive lymphoma are adults who exhibit generalized lymphadenopathy, B-symptoms, polyclonal hypergammaglobulinemia, skin rash and various autoimmune phenomena. 相似文献