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We studied the relationship between Osgood-Schlatter disease and torsional abnormalities of the lower limb in 21 boys with this condition and 20 age- and sex-matched controls. 3 groups of knees (20 control knees, 21 symptomatic and 21 asymptomatic or less symptomatic knees) were subjected to clinical, radiographic and CT evaluation. We found no statistically significant differences between patients and controls, as regards femoral anteversion, patellar congruence angle, patellar tilt angle and anterior tibial tuberosity-trochlear groove distance, but the condylomalleolar angle and tibial torsion angle were greater in patients. We found no differences between symptomatic and asymptomatic or less symptomatic knees in any of the parameters. All the symptomatic knees were on the side preferentially involved in jumping and sprinting. This increase in external tibial torsion may play a role as a predisposing mechanical factor in the onset of Osgood-Schlatter disease in male athletes.  相似文献   
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Omphalocele is the most common congenital defect of the abdominal wall. Mortality rate is between 20 and 70% and early closure of the abdominal wall, within 10 days of life, is vital to the successful outcome of the surgical treatment. The authors describe the use of two bipedicled flaps of abdominal skin to correct the defect of the midline as soon as the reduction of all viscera has been accomplished.  相似文献   
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By applying Seidel aberration theory we have studied the spherical aberration of intraocular lenses in place ( S IL), and the total spherical aberration of pseudophakic eyes ( S IT). The optimum lens shapes for zero S IL and S IT or for minimum S IL and S IT of 12 schematic, highly myopic eyes were investigated. When the power required for emmetropization is positive, the total Seidel spherical aberration of the whole eye cannot be zero but can only be minimized. If the power of the intraocular lens is negative, the total Seidel spherical aberration of the whole eye can be made zero, and one of the optimum lens shapes would be meniscus with the convex surface towards the retina. In addition to improving the quality of the image, the lens has advantages from the physiological point of view, since it helps to maintain the structure of the eye.  相似文献   
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Little has been done to investigate the biochemical basis of chronic daily headache (CDH). Our group has recently demonstrated an increase in the cerebrospinal fluid (CSF) levels of nerve growth factor (NGF) in CDH patients, supporting the involvement of this growth factor in the abnormal processing of head pain in this pathological condition. Other members of the neurotrophin family, especially brain-derived neurotrophic factor (BDNF), have been hypothesized as being involved in the development of chronic head pain in patients affected by CDH, but so far no data are available on this subject. BDNF, NGF and glutamate levels were determined in the CSF of 25 patients affected by CDH with a previous history of migraine. These levels were compared with those of a group of 20 control subjects, for whom the CSF examination and other instrumental investigations excluded diseases of the central and peripheral nervous systems. Significantly higher levels of BDNF, NGF and glutamate were found in CDH patients compared with control subjects (p<0.0001, p<0.0002 and p<0.001, respectively). A significant positive correlation emerged between CSF values of BDNF and those of NGF (r=0.61, p<0.001) and glutamate (r=0.44, p<0.025) in CDH patients. No significant differences were detected in BDNF, NGF and glutamate levels between CDH patients with analgesic overuse and those without. These results support the involvement of BDNF in CDH through the potentiation of glutamatergic transmission involved in the processing of head pain. The significant correlation between BDNF and NGF levels suggests that NGF-mediated up-regulation of BDNF in central sites involved in long-term sensitization plays a key role in persistent head pain in CDH patients. Correspondence to P. Sarchielli  相似文献   
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Background Optic disc anomalies are frequently associated with Alagille syndrome. We report here the first case of a patient with Alagille syndrome combined with optic pit and serous macular detachment. Methods A male patient with Alagille syndrome was referred from the pediatric hepatology department for investigation of visual loss in the right eye. Anterior segment examination showed evidence of posterior embryotoxon, confirmed by gonioscopic evaluation. Dilated fundus examination revealed serous macular detachment and optic pit. Results OCT 3 scans confirmed the clinical findings. Conclusions Optic pit is uncommon and should prompt a search for genetic disorders or development abnormalities. The association between the two syndromes in this patient might be due to failure of correct neuroectodermal development, for which a common genetic pathway is likely.  相似文献   
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Circumferential choledochoplasties with vascular grafts have rarely been attempted either experimentally or in clinical practice. In this study, choledochoplasties using autologous venous and arterial grafts were performed in rats. Sixty-four rats were randomly selected into five treatment groups: A) venous interpositional graft replacement of a choledochus gap without a stent; B) venous graft with prolene stent; C) venous graft with polyethylene stent; D) arterial graft; E) a control group with simple resection between ligatures in the choledochus. The operative mortality in treatment groups B, C, D, and E, was 0, and 13% in group A. At 12 weeks follow-up, all the rats in group E had died, whereas, 52.2% (P <.05) of the rats in group A, 30% of the rats in group B, 57% of the rats in group C, and 92.8% of the rats in group D survived treatment. Surviving animals were sacrificed at 3 months for further examination. The morphology and caliber of the common bile duct of these rats were normal in 25% of the rats in group A, 33% of the rats in group B, 25% of the rats in group C, and 84.6% of the rats in group D. Proximal dilations were found in the rats presenting with abnormal morphology. The dilations were less marked in the group treated by arterial choledochoplasties. Laboratory and clinical cholestatic parameters were within normal ranges in the presence of common bile duct dilations less than four times the normal duct caliber. Electron microscopic examination of the venous and arterial graft at 3 months follow-up revealed a fibrous ring composed of collagen fibers, fibroblasts, and remnants of elastic fibers. Regenerated ductal epithelium encompassed both types of grafts. Epithelialization was more pronounced in venous grafts as compared to arterial grafts. Biliary epithelium was able to colonize the venous grafts and resume cell specialization and function as in normal biliary epithelium. The most satisfactory results were obtained using venous grafts with stents or by using arterial grafts. © 1993 Wiley-Liss Inc.  相似文献   
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