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41.
We describe herein a rare case of primary malignant melanoma of the rectum in an 85-year-old woman. The patient presented with intermittent rectal bleeding, and a colonoscopy revealed an ulcerated polypoid mass in the rectum, located 5 cm from the anal verge. The lesion was histologically characterized by solid growths of small round cells with scanty cytoplasm and prominent nucleoli. Although no melanin pigment was found in the tumor cells, they were immunohistochemically positive for HMB-45, a monoclonal antibody highly specific for malignant melanoma. Thus, HMB-45 proved very useful to establish a diagnosis of amelanotic malignant melanoma of the rectum.  相似文献   
42.
Abstract: Two autopsied female sibling cases of sudanophilic leukodystrophy are reported. Case A and case B were the second and third of seven siblings, and a sister and a brother died from severe progressive neurological disease with similar symptoms. Consanguineous marriages were noted in the family of both cases through the past three generations. Case A gradually developed intellectual deterioration and tetraplegia at the age of 29, progressed to akinetic mutism within one year and thereafter survived for 14 years. Neuropathologically, a severe atrophy and degeneration were noted in the white matter of the whole cerebrum, sparing the subcortical U-fibers. Myelin and axons were severely damaged with peripheral astrocytic gliosis. Case B developed similar clinical symptoms at the age of 20 and survived for 7 years in the state of akinetic mutism. Similar postmortem findings as those of case A were found in the white matter of the cerebrum with formation of sudanophilic breakdown products and with thick fibrillary gliosis. The pyramidal tract was completely degenerated. There was no accumulation of abnormal lipid in the brains of both cases.  相似文献   
43.
Background The purpose of this study was to examine the effects of bacterial suporantigens, which can derange the immune response and contribute to the renal lesions of immunoglobulin A (lgA) nephropathy. Methods Twenty-five micrograms of a bacterial superantigen, staphylococcal enterotoxin B (SEB), was injected into IgA nephropathy-prone ddY mice intrathymically when they reached 6 weeks of age. Evaluation included measurement of albumin excretion in urine, immunoglobulin concentration, and lymphokine production in vitro, as well as analysis of T-cell receptor expression in splenic T-cell subsets and examination of renal histology by light and fluorescence microscopy. Results At 40 weeks of age, the serum level of IgA in these mice was substantially increased and the number of Vβ8+ CD4+splenic T-cells was significantly decreased compared with measurements in untreated controls. Both control and SEB-treated mice excreted less than 30 μg/mL of urinary albumin. In mice given SEB, the amount of interleukin 2 (IL-2) and tumor necrosis factor-α (T helper 1 [Th1]-type cytokines) produced by the in vitro-stimulated lymphocytes significantly decreased. whereas that of interleukin 4 (IL-4) and interleukin 6 (IL-6) (Th2-type cytokines) markedly increased compared with measurements in control mice. At 40 weeks of age, mice given SEB showed marked glomerular hypercellularity and enhanced glomerular C3 deposition by renal histology, compared with control mice. Conclusion These results suggest that bacterial superantigen SEB may modify glomerular lesions through activating Th2 cells, while inducing deletion of Th1 cells in this experimental model.  相似文献   
44.
We report herein the case of a premature infant with esophageal atresia (EA) and a tracheoesophageal fistula (TEF) associated with cardiac anomalies who was successfully treated by an early ligation of the TEF following gastrostomy, and delayed repair of the esophagus. A 1212-g male was born prematurely at 31 gestational weeks, at which time he was diagnosed as having EA with TEF and patent ductus arteriosus (PDA), ventricular septal defect (VSD), and atrial septal defect (ASD). A gastrostomy was initially performed but following extubation he gradually became tachypneic. A chest roentogenogram revealed atelectasis and ground-glass appearance, and reintubation was required. Ligation of the TEF was performed 53h after his birth. Following the improvement of his respiratory condition through ventilatory support and the intratracheal administration of pulmonary surfactant, he underwent repair of the esophagus on the 6th day of life. Postoperatively, he suffered from heart failure, but was treated with peritoneal dialysis and pharmacological closure of the PDA. Weaning the infant from the ventilator proved difficult, but it was finally achieved when he had reached a weight of 2268g at 3 months of age by enteral feeding. Our experience of this case demonstrates that early ligation of TEF should be performed for a premature infant with EA and TEF before respiratory distress syndrome (RDS) has developed. If a gastrostomy is required to prevent gastric distention, it should be followed by simultaneous or immediate ligation of the TEF.  相似文献   
45.
Between January 1985 and September 1994, 21 patients with psychiatric disorders underwent various forms of surgery at our hospital. There were 12 men and 9 women with an average age of 57.6 years. The coexisting psychiatric disorders were schizophrenia in 15 patients, depression in 2, dementia in 2, mental retardation with epilepsy in 1, and Parkinson's disease in 1. All the patients had been receiving neuroleptic medications for a long period. The indications for surgery were: cholelithiasis in 6 patients, acute appendicitis in 4, perforation of the small intestine in 3, incarceration of an inguinal hernia in 2, and esophageal cancer, stomach cancer, bleeding from a gastric ulcer, perforation of a duodenal ulcer, strangulating ileus, and burns in 1 patient each, respectively. All of the patients who underwent elective surgery were given epidural anesthesia with or without general anesthesia. Antipsychotic medications were given until just prior to surgery and recommenced concurrent with the first meal. Abnormal behavior was observed in 11 patients (52.4%) postoperatively, but all the patients were discharged in accordance with recovery from their surgical disorder. Intra- and postoperative hypotension resistant to intravenous catecholamine administration was recognized in 9 patients (42.9%), and this peculiar complication should be borne in mind when patients with psychiatric disorders require surgical management. Presented at the 94th annual meeting of the Japanese Surgical Society, held in Tokyo in March, 1994  相似文献   
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48.
We reported a case of the biliary cystadenoma of the liver. The cystic mass had labulation and septation and showed marked hyperintensity on T1-weighted images and hypointensity on T2-weighted images; MR findings were very unusual for cystadenoma. The content of the cystic mass was jelly-like, thick mucinous fluid without intracystic hemorrhage. We concluded that these unusual signal intensities of the cyst were due to hyperproteinous mucinous fluid.  相似文献   
49.
Familial occurrence of differentiated, nonmedullary thyroid carcinoma in 23 patients from 11 families is reported. Five patients were male and 18 were female. The familial relationship of patients was parent and child in 12 cases from 6 families, and siblings in 11 cases from 5 families. Carcinoma of other organs was noted in other members in 8 families. Histological examination revealed 18 papillary, 2 follicular, and 2 anaplastic carcinomas (the 2 anaplastic carcinomas were considered to be transformed from preexisting differentiated carcinoma). In 1 case, the histological type was unknown. The average diameter of the primary lesion was 29.9 mm. Cervical lymph node metastasis was found in 77.8% and local recurrence in 28.6% of the patients. Solid and invasive growth was dominant. On HLA typing, phenotypes of B7 and DR1 were significantly redominant in familial patients compared with nonfamilial patients and normal Japanese. Moreover, the haplotype of B7-Cw7-DR1 was observed in 5 of 13 patients tested. It is suggested from these observations that some types of differentiated, nonmedullary thyroid carcinoma may show familial occurrence and that they may have common factors with regard to the genetic and immunologic basis of the disease.
Resumen Se informa la ocurrencia familiar de carcinoma bien diferenciado, no medular, de tiroides en 23 pacientes provenientes de 11 familias, 5 hombres y 18 mujeres. La relación familiar fue padre e hijo en 12 casos de 6 familias, y hermanos en 11 casos de 5 familias. Se observé la presencia de carcinoma de otros órganos en otros miembros de 8 familias. El examen histopatológico reveló 18 carcinomas papilares, 2 foliculares, y 2 anaplásicos (los 2 fueron considerados como transformación de carcinomas diferenciados preexistentes). En un caso no fue conocido el tipo histológico. El diámetro promedio de la lesión primaria fue 29.9 mm. Se hallaron metástasis en ganglios cervicales en 77.8% de los pacientes y recurrencia local en 28.6%. El crecimiento sólido e invasivo apareció como característica dominante. En la tipificación HLA aparecieron como significativamente predominantes los fenotipos de B7 y DR1 en pacientes familiares en comparación con pacientes no familiares y japoneses normales. Por otra parte, el halotipo de B7-CW7-DR1 fue observado en 5 de 13 pacientes investigados.Como resultado de estas observationes se sugiere que algunos tipos de carcinomas diferenciados, no medulares, pueden demostrar ocurrencia familiar y que pueden poseer factores comunes relacionados con las bases genéticas e inmunológicas de la enfermedad.

Résumé On a étudié les caratéristiques du cancer de la thyroïde, dans sa variété différenciée non médullaire, survenu chez 23 patients provenant de 11 familles. Cinq patients étaient des hommes, 18 des femmes. La relation familiale était parent/enfant dans 12 cas provenant de 6 familles, et frère/soeur dans 11 cas provenant de 5 familles. Des membres de 8 autres familles présentaient un cancer d'un autre organe. Il y avait 18 cancers papillaires, 2 cancers folliculaires, et 2 cancers anaplasiques (on a considéré que les 2 cancers anaplasiques étaient des transformations à partir de cancers différenciés préexistants). Dans un cas, le type histologique était inconnu. Le diamètre moyen de la lésion primitive était de 29.9 mm. On a retrouvé des métastases ganglionnaires cervicales chez 77.8% des patients et une récidive locale chez 28.6%. Les tumeurs étaient principalement solides et invasives. Par rapport aux cancéreux non familiaux et à la population japonaise normale, il y avait plus de phénotypes B7 et DR1 au système HLA. L'haplotype B7-CW7-DR1 était observé chez 5 des 13 patients testés.On suggère que certains types de cancer différenciés, non médullaires, ayant des facteurs communs génétiques et immunologiques, peuvent survenir dans une même famille.


Presented at the International Association of Endocrine Surgeons in Sydney, Australia, September, 1987.  相似文献   
50.
Bruch's membrane exists between the retinal pigment epithelium and the choriocapillary endothelium. Its structure is very complicated, having five sublayers containing basement membranes of retinal pigment epithelium and choriocapillary endothelium, outer and inner collagenous layers, and a central elastic layer. In the development of Bruch's membrane in normal mice, both basement membranes are created first. Secondarily, collagen fibers are accumulated in the space between these basement membranes and then form a collagenous layer. Finally, the elastic layer elaborated in the collagenous layer separates this into outer and inner collagenous layers. Brachymorphic mice have a disorder in the sulfation pathway, resulting in undersulfation. Consequently, in Bruch's membrane of brachymorphic mice, the expression of decorin, a small proteoglycan containing chondroitin sulfate and an indispensable component in collagen assembly, is at a very low level. It is clear that hypoplasia of the collagenous layer in Bruch's membrane of brachymorphic mice induces a disorder in the following formation of the elastic layer. These findings suggest that the formation of the collagenous layer, regulated with acidic glycoconjugates such as decorin, is important in the development of Bruch's membrane.  相似文献   
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