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91.
OBJECTIVE: A Tracheomalacia complicates 11-33% of cases of Oesophageal Atresia with distal Tracheo-Oesophageal Fistula. The lesion generally involves only the thoracic segment of the trachea, and it has close anatomical relationships with the mediastinal structures, specially with the aortic arch. We therefore tried to define the most important morphotypes of tracheobronchial malacia by using dynamic fiberoptic bronchoscopy (DFB) and spiral multilayer computed tomography (CT). METHODS: Between 1999 and 2003 we studied 40 children from two different institutions who had been operated on at birth for oesophageal atresia. All patients were been submitted to DFB, and the positive cases underwent examination by CT with an iodinated contrast medium. CT angiographic images of great vessels and multiplanar and three-dimensional images of the airways (virtual broncoscopy and broncography) were obtained for morphological evaluation. RESULTS: Twenty-five patients (62%) tested positive for malacia using DBF and all were also confirmed by CT study. In 11 cases (46%), the malacia was located at the thoracic section of the trachea, which was occluded by compression of the aorto-innominate complex. A simple intrinsic tracheomalacia without any vascular compression was present in eight cases (33%), while in five cases (21%), the malacia was complex. CONCLUSIONS: A correct morphological analysis of the malformed segment permitted 'tailored surgery' for each individual patient, allowing us to take account of the type of malacia, its length, and the compressive action exercised by the mediastinal great vessels.  相似文献   
92.
93.
We have studied the lateral rectus muscles and neuromuscular junctions (NMJs) of abducens motoneurons in wobbler (wr/wr) mutant mice from 26 to 58 days of age. The muscles of wr/wr weighed about 70% of the weight of littermate controls and were composed of fiber types comparable to those of controls, as assayed by succinate dehydrogenase activity. The most obvious difference between wr/wr and control NMJs was a reduction in the length of the postjunctional membrane of wr/wr mice. The mutant muscle endplate membrane was only about 70% (6.58 micron) the length of control muscle regions (9.44 micron). There were no obvious differences at the light microscopic level in the distribution of acetylcholine (ACh) receptors at junctional regions or staining of acetylcholinesterase, as assayed with alpha-bungarotoxin binding or enzyme histochemistry. Indirect immunocytochemical studies using antibodies directed against the subunits of the ACh receptor failed to indicate an abnormal presence of immature receptors clustered at the NMJs of wr/wr mice. Our findings suggest that the formation or maintenance of normal postjunctional folds and the differentiation of receptors at the junctions are under independent control during development. Furthermore, the wobbler mutation may affect muscle cell differentiation as well as neuronal differentiation. This mutant mouse should prove a useful model for study of postjunctional fold formation and function.  相似文献   
94.
Alpha-1-antichymotrypsin in renal biopsies   总被引:1,自引:0,他引:1  
Alpha 1-Antichymotrypsin (alpha 1-AK) and alpha-1-antitrypsin (alpha 1-AT) represent a defense mechanism to protect the tissues from proteolytic enzyme activity. We studied the implication of alpha 1-AK and alpha 1-AT in glomeruli of patients with different nephropathies based on the analysis of 52 paraffin-embedded renal biopsies with alpha 1-AK and alpha 1-AT antisera. The results demonstrate an intense alpha 1-AK glomerular staining in renal biopsies from patients with minimal-change disease, while a minor staining of this protein was found in the other nephropathies. No significant evidence of alpha 1-AT deposits was observed in our cases. Our findings suggest that when alpha 1-AK is lacking in glomeruli the defense mechanisms against proteolytic enzymes may not be efficient enough to protect the glomerular structures and limit the damage. Since alpha 1-AK is a reactant of the acute phase of inflammation, it may be considered as a marker of activity for monocyte-macrophages in glomerular damage.  相似文献   
95.
In 1980, the ratio of home birth to public hospital perinatal and neonatal mortality rates decreased from Northern to Southern Italy, being inversely related to the proportion of home deliveries and probably reflecting the effect of planned versus unplanned home births. The post neonatal mortality rate in Southern Italy was about four times as high in children born at home (9.5/1,000 live births) than in those delivered in public hospitals (2.6/1,000 live births), probably reflecting differences in the socioeconomic status according to the birthplace selection in various regions.  相似文献   
96.
OBJECTIVE: Our purpose was to investigate immunosuppressive acidic protein in the prognostic characterization of advanced ovarian cancer. STUDY DESIGN: Serum levels of immunosuppressive protein were prospectively measured in 80 patients with untreated ovarian carcinoma. To evaluate the prognostic significance of immunosuppressive acidic protein levels, cutoff points were studied every 50 μg/ml between 450 and 1350 μg/ml. RESULTS: Pretreatment immunosuppressive acidic protein levels were not significantly associated with stage, histotype, grade of differentiation, postoperative residual tumor, and response to chemotherapy. The most significant association with survival was observed at a cutoff value of 1100 μg/ml (p = 0.0089). In the univariate analysis for overall survival, International Federation of Gynecology and Obstetrics stage and immunosuppressive acidic protein status were found to have a role in predicting ovarian cancer prognosis. In the multivariate analysis only immunosuppressive acidic protein status was significantly associated with survival. A statistical correlation was found between serum levels and overall survival (p = 0.0104, χ2 6.56), including immunosuppressive acidic protein as a continuous variable. CONCLUSION: Our data suggest that immunosuppressive acidic protein assay is a potentially useful tool in the prognostic characterization of advanced ovarian cancer. (Am J Obstet Gynecol 1996;175:1606-10.)  相似文献   
97.
The case is described of a 73 year old man who presented with a lupus-like syndrome related to treatment with isoniazid and had IgG antinuclear antibodies against the nucleo-histone complex (H2A-H2B)-DNA. After a short course of treatment with prednisone and discontinuation of isoniazid the patient's lupus symptoms resolved and a gradual decrease in antibodies to (H2A-H2B)-DNA occurred. This case suggests that isoniazid is capable of inducing an autoantibody specificity associated with drug related lupus.  相似文献   
98.
Results of 33 simultaneous pancreas and kidney transplantations performed at the San Raffaele Hospital, Milan, Italy are presented. In 26 cases segmental neoprene duct-injected grafts were transplanted and in seven cases, duodenopancreatic bladder-drained grafts. Five-year patient, kidney and pancreas survival were respectively, 89%,72% and 58%. Five-year survival in patients with technically successful pancreas transplants was 73%. Thrombosis occured in 20% of cases. Mortality was 6% and overall morbidity 76%. Surgical complications were present in 51% of cases.  相似文献   
99.
People undergoing medical procedures sometimes experience feelings that may influence the results. In this study, we explore the relationship between changes in mood state self-ratings and cerebral glucose metabolism during positron emission tomography (PET) in persons with age-associated memory impairment (mean age 59.4±9.8 years). Brain regions of interest involved in both mood and memory were examined. Mood ratings of increased boredom correlated significantly with mesial temporal and parietal asymmetry and decreased parietal metabolism. Mood ratings of increased fatigue correlated with basal ganglia asymmetry and the right basal ganglia and left mesial temporal metabolism. These findings suggest that subjective mood state changes during PET may influence metabolism in brain regions implicated in emotion and memory function in people with age-related memory complaints.  相似文献   
100.
We identified large-scale heteroplasmic mitochondrial DNA (mtDNA) rearrangements in a 50–year-old woman with an adult-onset progressive myopathy. The predominant mtDNA abnormality was a 21.2–kb duplicated molecule. In addition, a small population of the corresponding partially deleted 4.6–kb molecule was detected. Skeletal muscle histology revealed fibers that were negative for cytochrome c oxidase (COX) activity and had reduced mtDNA-encoded COX subunits. By single-fiber polymerase chain reaction analysis, COX-negative fibers contained a low number of wild-type or duplicated mtDNA molecules (ie, nondeleted). In situ hybridization demonstrated that the abnormal fibers contained increased amounts of mtDNA compared with normal fibers and that most of the genomes were deleted. We concluded that deleted mtDNA molecules were primarily responsible for the phenotype in this patient.  相似文献   
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