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51.
Blood gas analysis can be used to reliably predict outcome in infants with congenital diaphragmatic hernia (CDH) both before and after surgical repair, providing these values are indexed to some measurement of alveolar ventilation. Until recently there has been difficulty in interpreting some of the published data because of differing sampling sites and the fact that ventilatory parameters, which have major influences on all blood gas values in this anomaly, were not included. Application of this information enables us to identify infants with similar degrees of severity of CDH in order to evaluate the efficacy of novel forms of therapy and to determine whether they represent a genuine advance in management where more conventional forms of treatment have failed.  相似文献   
52.
While attrition from sharp bony surfaces is the most common cause of extensor digiti minimi (EDM) tendon rupture, the etiology of other cases of spontaneous EDM tendon rupture is still unknown. Friction within the compartment may play a role, especially with ulna dislocation. The purpose of this study was to compare gliding resistance of the EDM tendon with that of a tendon which rarely ruptures spontaneously, the extensor digitorum communis of the middle finger (EDC III) tendon, under various wrist and ulna head positions. Eight fresh frozen cadavers were used. Gliding resistance between the tendon and its sheath in each compartment was measured in five different wrist positions and three different ulna head positions. Gliding resistance of the EDM tendon (0.13 +/- 0.03 N) was significantly greater than the EDC III tendon (0.09 +/- 0.03 N) (p < 0.05). For the EDM tendon, the gliding resistance in ulnar deviation or pronation was higher than the gliding resistance in neutral, radial deviation, or supination (p < 0.05), and the gliding resistance with ulnar lengthening (over 6 mm) or dorsal ulnar dislocation (over 9 mm) was higher than in neutral ulnar head positioning. For the EDC III tendon, the gliding resistance in ulnar deviation was significantly higher than the gliding resistance in neutral, radial deviation, or supination, or dorsal dislocation with ulnar lengthening (p < 0.05). Wrist ulnar deviation, ulnar dorsal dislocation (over 9 mm), and ulnar lengthening (over 6 mm) increased the gliding resistance of the EDM tendon. In patients at risk for EDM rupture, such as those with rheumatoid arthritis or distal radioulnar joint osteoarthritis, avoiding such positions may be advantageous.  相似文献   
53.
Laryngotracheoesophageal cleft is an uncommon disease that is difficult to diagnose and treat. Repair of the cleft depends on length and localization of the defect as well as the associated anomalies. A successful repair of a type II cleft is reported in this paper. An anterior split of the larynx and trachea was used and provided excellent exposure and safe repair without injury to the neurovascular structures. This is the best approach and should be used to correct all type II defects.  相似文献   
54.
The authors studied 34 patients with juvenile ischemic cerebrovascular disease over a 15-year period. Of the 34 patients, 23 had intracranial occlusions attributed to cerebral thrombosis or embolism and 11 had occlusions resulting from moyamoya disease. Clinicopathological features were evaluated in the 23 cases with ischemic stroke, but not those with moyamoya disease. The cause of the arterial occlusion remained undetermined in 11 patients and was found to be an embolism based on congenital heart disease in 8, on trauma in 3, and on infection in 1. Cerebral angiography was performed in 21 patients. Of these, 17 had stenoses or occlusions corresponding to their symptoms. CT scans were performed in 10 patients; the lesion in question showed no stenosis or occlusion with cerebral angiography. With regard to prognosis, patients with unknown etiology had good outcomes compared with those with congenital heart disease. With respect to acute infantile hemiplegia, 10 patients had convulsive seizures and 4 had a history of an earlier infection. Angiography and CT scans in patients with congenital heart disease demonstrated arterial occlusive sites in the middle cerebral artery region. Three patients had abscesses after their ischemic lesions.  相似文献   
55.
Genetics of congenital hyperinsulinism   总被引:4,自引:0,他引:4  
Congenital hyperinsulinism (CHI) is a clinically and genetically heterogeneous entity and causes severe hypoglycemia in neonates and infants. The clinical heterogeneity is manifested by severity ranging from extremely severe, life-threatening disease to very mild clinical symptoms, which may even be difficult to identify. Furthermore, clinical responsiveness to medical and surgical management is extremely variable. Recent discoveries have begun to clarify the molecular etiology of this disease in about 50% of cases. Mutations in five different genes have been identified in patients with this clinical syndrome. Most cases are caused by mutations in the genes ABCC8 and KCNJ11 coding for either of the two subunits of the beta-cell KATP channel (SUR1 and Kir6.2). Recessive mutations of the beta-cell K(ATP) channel genes cause diffuse HI, whereas loss of heterozygosity together with inheritance of a paternal mutation causes focal adenomatous HI. In other cases, CHI is caused by mutations in genes coding for the beta-cell enzymes glucokinase (GK), glutamate dehydrogenase (GDH), and SCHAD. However, for as many as 50% of the cases, no genetic etiology has yet been determined. The study of the genetics of this disease has provided important new information regarding beta-cell physiology.  相似文献   
56.
Infradiaphragmatic extralobar pulmonary sequestration is an extremely rare congenital malformation. It is more frequently diagnosed in the antenatal period due to routine ultrasonic examination of the fetus or in the first 6 months of life, though on rare occasions it is discovered incidentally in adults. A 32-yr-old man presenting with epigastric discomfort and fever was referred. Computed tomographic scanning showed that a 16-cm, multiseptated, dumbbell-shaped, huge cystic tumor was located beneath the diaphragm. On the next day, 850 mL of thick yellowish pus was drained by sonography-guided fine needle aspiration for the purpose of infection control and diagnosis, but no microscopic organisms were found in repeated culture studies. Surgical removal of the cyst was performed through thoracoabdominal incision and most of these pathologic lesions were removed but we could not find the feeding arteries or any fistulous tract to surrounding structures. Histopathologic study revealed that it was extralobar pulmonary sequestration and culture study showed that many WBC and necrotic materials were found but there were no microorganisms in the cystic contents. We report the first case of an infected infradiaphragmatic retroperitoneal extralobar sequestration which was administered a staged management and achieved an excellent clinical course.  相似文献   
57.
Chromosome 1p36 deletion syndrome is characterized by hypotonia, moderate to severe developmental and growth retardation, and characteristic craniofacial dysmorphism. Muscle hypotonia and delayed motor development are almost constant features of the syndrome. We report a 4-year-old Japanese girl with 1p36 deletion syndrome whose muscle pathology showed congenital fiber type disproportion (CFTD) myopathy. This is the first case report of 1p36 deletion associated with CFTD. This association may indicate that one of the CFTD loci is located at 1p36. Ski proto-oncogene −/− mice have phenotypes that resemble some of the features observed in patients with 1p36 deletion syndrome. Because fluorescent in situ hybridization analysis revealed that the human SKI gene is deleted in our patient, some genes in 1p36, including SKI proto-oncogene, may be involved in muscle hypotonia and delayed motor development in this syndrome. Received: March 4, 2002 / Accepted: July 7, 2002  相似文献   
58.
We report on the expression of growth associated protein (GAP)43 and neural cell adhesion molecule (NCAM) in congenital fibre type disproportion (CFTD) with myopathological additional signs of interstitial myositis. We assume that sarcolemmal GAP43 in developmental disordered myocytes plays a role in maintenance of growth morphology. In muscular dystrophy light microscopical evaluation reveals no GAP43 immunoreactivity in regenerating fibres. The expression of GAP43 seems to be a characteristic feature of CFTD. The expression of NCAM, particularly in the sarcolemma of small muscle fibres of CFTD, indicates a functional state of permanent partial denervation. Whether the steroid-responsive interstitial myositis is pathogenetically related to CFTD or a coincidental inflammation is not known. Because of the clinical and myopathological data the differential diagnosis of Emery-Dreifuss muscular dystrophy is considered.  相似文献   
59.
The inherited inability to synthesize cortisol is termed congenital adrenal hyperplasia. More than 90% of cases are caused by 21-hydroxylase deficiency. This syndrome is characterized by signs of androgen excess and often mineralocorticoid deficiency. Steroid 21-hydroxylase (P450c2l) is a microsomal enzyme expressed in the adrenal gland that catalyzes conversion of 17-hydroxyprogesterone and progesterone to 11-deoxycortisol and deoxycorticosterone respectively. In man, this enzyme is encoded by the CYP21 (CYP21B) gene which is located in the HLA major histocompatibility complex along with a pseudogene, CYP21P (CYP21A). Mutations in CYP21 causing congenital adrenal hyperplasia are almost all generated by recombinations between CYP21 and CYP21P. These recombinations either delete CYP21 or transfer deleterious mutations from CYP21P to CYP21, a process termed apparent gene conversion. The degree of enzymatic compromise caused by each mutation is correlated with the clinical severity of the deficiency observed in patients carrying that mutation. © 1994 Wiley-Liss, Inc.  相似文献   
60.
Summary Two unrelated patients with severe arthrogryposis multiplex congenita (AMC) who died perinatally, are presented. In both, postmortem examination revealed an intact nervous system and striking dystrophic muscle changes, consistent with congenital muscular dystrophy (CMD). Few similar cases have been reported before, but since the condition is not well known, it seems probable that in the past many have been labeled as mere multiple malformations. The possibility of an underlying muscular disorder, either primary myopathic or neurogenic should be considered in any patient with early lethal AMC. Our findings confirm that the fetal akinesia-arthrogryposis sequence is a nonspecific clinical syndrome resulting from various causes of muscular inactivity in utero. The main objective of this report is to provide reasonable guidelines on how to approach the problem of classification. We favor a pathogenetic approach, depending upon careful sampling of the central nervous system and skeletal muscles at autopsy.  相似文献   
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