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The vascular anatomy of the pronator quadratus muscle and distal radius was studied in 24 cadaveric forearms by dissection under magnification and india ink and latex injection studies. The anterior interosseous artery divides into a muscular branch and a dorsal branch 1 cm to 3.5 cm from the proximal margin of the pronator quadratus muscle, and on its deep surface. Injection studies showed a rich periosteal plexus contributed by the anterior interosseous artery. Retrograde injection through the dorsal branch also showed good perfusion of the distal radius that was confirmed microscopically on bone sections. A muscle-bone graft from the anteromedial cortex of distal radius with an intact anterior interosseous artery has mobility of less than 2 cm. After ligating and dividing the anterior interosseous artery, blood supply to the distal radius bone flap relies on a retrograde flow and the bone flap could then be mobilized distally up to 4 to 6 cm.  相似文献   
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Previously, we reported that transgenic mice overexpressing endothelin-1 in astrocytes showed more severe neurological deficits and increased infarct after transient focal ischemia. In those studies, we also observed increased level of aldose reductase (AR), the first and rate-limiting enzyme of the polyol pathway, which has been implicated in osmotic and oxidative stress. To further understand the involvement of the polyol pathway, the mice with deletion of enzymes in the polyol pathway, AR, and sorbitol dehydrogenase (SD), which is the second enzyme in this pathway, were challenged with similar cerebral ischemic injury. Deletion of AR-protected animals from severe neurological deficits and large infarct, whereas similar protection was not observed in mice with SD deficiency. Most interestingly, AR(-/-) brains showed lowered expression of transferrin and transferrin receptor with less iron deposition and nitrotyrosine accumulation. The protection against oxidative stress in AR(-/-) brain was also associated with less poly(adenosine diphosphate-ribose) polymerase (PARP) and caspase-3 activation. Pharmacological inhibition of AR by Fidarestat also protected animals against cerebral ischemic injury. These findings are the first to show that AR contributes to iron- and transferrin-related oxidative stress associated with cerebral ischemic injury, suggesting that inhibition of AR but not SD may have therapeutic potential against cerebral ischemic injury.  相似文献   
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Frontal intracerebral haemorrhage (ICH) is a common result of cranial trauma. Outcome differences between bilateral and unilateral frontal ICH are not well studied but would be valuable to predict prognosis in clinical practice. Two aims are proposed in this study: first to compare the risk of developing delayed ICH after bilateral or unilateral frontal ICH, and second to determine the variables helpful to predict outcome according to the Glasgow Outcome Scale (GOS). Between January 1993 and December 1997, 694 consecutive patients with traumatic ICH were admitted to the Chang Gung Medical Center within 24 h of the trauma. Patients with ICH in sites other than the frontal lobes were excluded. A total of 161 cases (mean age 46.3+/-20.3 years), including 57 bilateral (mean age 52.5+/-18.7 years) and 104 unilateral (mean age 42.9+/-20.5 years) traumatic frontal ICH were studied. Twenty-eight of 57 patients (49%) with bifrontal ICH versus 17 of 104 patients (16%) with unilateral frontal ICH had a further, delayed ICH. In 42 of 45 patients (93%) with delayed ICH, this occurred within 5 days of the initial trauma. Multivariate logistic regression was used to select significant predictors of outcome. We found that delayed ICH (p<0.001), age (p=0.004) and mechanism of injury (p=0.001) explained the worse outcome in patients with bifrontal ICH. The best-fitting logistic regression model included three variables: delayed ICH (p=0.011), initial GCS (p=0.023), and a sum score of clinical and radiological variables (p=0.003). Bifrontal ICH tended to occur in older patients after a fall and was associated with a higher risk of developing delayed ICH or brain stem compression compared to unilateral ICH damage. Using these three variables - delayed ICH, initial GCS, and the sum score - in a logistical regression model is useful to predict outcome in patients with traumatic frontal ICH and may aid patient management.  相似文献   
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BACKGROUND AND PURPOSE: There are limited data on the pattern of cancer distribution among adolescents in Taiwan. This study evaluated the characteristics of these rare cancers in a medical center. METHODS: Analyses of the characteristics of malignant neoplasms for patients aged 14 to 17 years at diagnosis were performed for all cases recorded in the tumor registry of Chang Gung Memorial Hospital (CGMH) at Linkou for the period 1995 to 2001. All eligible tumors were categorized in 1 of 12 diagnostic groups according to the scheme of the International Classification of Childhood Cancer (ICCC). Relative frequencies, age, and gender variations and the characteristics of tumor types were analyzed. RESULTS: Cancer was diagnosed in 320 adolescents during the study period. The male/female ratio was 1.17. Leukemia was the leading diagnostic group. The frequency of carcinomas increased with age and was highest among 17-year-olds. In this age group, non-rhabdomyosarcoma soft tissue sarcoma/primitive neuroectodermal tumor (non-RMS STS/PNET), thyroid carcinoma (CA) and ovarian germ cell tumor (GCT) were the 3 most common solid tumors; the embryonal malignancies were rare. Tumors with the greatest male predominance were intracranial GCT (91%), nasopharyngeal CA (87.5%), osteosarcoma (84.6%), and colorectal CA (75%). Tumors with the greatest female predominance were thyroid CA (78.3%), gonadal GCT (75%), and non-RMS/PNET (56.5%). Hepatocellular CA comprised 9.4% of all carcinomas. CONCLUSIONS: The relative frequency and the distribution of histology subtypes among adolescents were between those of childhood and adult cancers. There were marked variations in tumor occurrence between genders and among different ages.  相似文献   
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Urethral reconstruction with graft substances, such as skin and bladder mucosa, has been previously used when primary anastomosis cannot be achieved. However, stricture and meatal prolapse are associated with these grafts. We report the use of buccal mucosa for the reconstruction of urethral defects in 3 patients. One patient with failed operation for hypospadias received tube buccal mucosal graft for urethral replacement. Two patients with urethral necrosis and stricture received onlay buccal mucosal graft. All patients were disease-free during follow-up (range, 12 to 49 months; mean, 36 months). One patient had a pinhole fistula that was successfully managed with simple repair. This technique appears to be useful for urethral reconstruction when a local graft is not available, even in patients with complicated conditions.  相似文献   
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