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91.
Immunohistochemical determination of the class of intermediate filaments (keratins, vimentin, desmin, neurofilaments, and glial fibrillary acidic protein) expressed by tumors has become an important diagnostic procedure for the histogenetic classification of neoplasms. A case of a poorly differentiated malignant neoplasm of the maxillary alveolar ridge which coexpressed keratin and desmin types of intermediate filaments is reported. These intermediate filaments have been associated with epithelial and muscle cell differentiation, respectively. The morphologic features of the tumor plus the expression of both these intermediate filaments indicate that this neoplasm represents a true carcinosarcoma.  相似文献   
92.
Over a 10-year period, 276 pulmonary arteriovenous malformations (PAVMs) were occluded with balloon embolotherapy in 76 patients, 67 (88%) of whom had hereditary hemorrhagic telangiectasia. Eleven patients (14%) were discovered by means of family screening with measurement of arterial blood gases and chest radiography. Epistaxis, dyspnea, hemoptysis, and hemothorax occurred in 79%, 71%, 13%, and 9% of patients, respectively. Clinical histories of strokes and transient ischemic attacks were present in 18% and 37% of patients, respectively. Computed tomographic scans of 59 patients showed stroke in 36%. Sixty-five percent of PAVMs were located in the lower lobes, which correlated with the finding of more pronounced hypoxemia in the upright position. After embolotherapy, symptomatic hypoxemia was corrected, and serial values have remained constant for 5 years. Complications were minimal, and no patient required surgery. Balloon embolotherapy is effective long-term therapy for PAVMs, and family screening should be pursued because of the possibility of a higher frequency of paradoxical embolization (stroke) than previously recognized.  相似文献   
93.
BACKGROUND: The pattern of growth of the uterus was examined by ultrasound examinations of 358 girls who attended a paediatric endocrine outpatient department but were shown not to have any endocrine defect. METHOD: The uterus was measured in length and width at the cervix and at the fundus (cm). Endometrial thickness was measured (mm). Scans were divided by Tanner breast stage and the dimensions compared by one way analysis of variance (ANOVA, with the Student Newman Keuls post hoc test). RESULTS: There was an increase in uterine length, diameter of the fundus, and endometrial thickness at each breast stage from 1 to 5 (ANOVA, p < 0.05), and in the diameter of the cervix with each breast stage from 1 to 4 (ANOVA, p < 0.05). The ratio of the fundus to the cervix increased from 0.95 to 1.29 between breast stages 1 and 4. CONCLUSION: The onset of puberty is marked by an increase in the dimensions of the uterus and in endometrial thickness, but also by a change in the shape of the uterus from a tubular to a pear shaped organ.  相似文献   
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We report 28 cases of atypical decubital fibroplasia, a distinctive pseudosarcomatous fibroblastic proliferation occurring primarily but not exclusively in physically debilitated or immobilized patients. The subjects included 16 women and 12 men ranging in age from 15 to 95 years. Peak incidence was in the 8th and 9th decades of life. Anatomic locations included the soft tissues overlying the shoulder (eight cases), posterior chest wall (five cases), sacrum (five cases), greater trochanter (four cases), buttock (two cases), thigh (two cases), and arm (two cases). Symptoms were due to a painless mass of 3 weeks' to 6 months' duration. Most lesions were ill-defined, focally myxoid masses that ranged from 1 to 8 cm. Histologically, they were situated in the deep subcutis and secondarily involved adjacent skeletal muscle (11 cases) and tendon (three cases). Extensive epidermal ulceration was typically absent. Microscopically, the lesions had a lobular configuration. They were characterized by zones of fibrinoid necrosis and a prominent myxoid stroma rimmed by ingrowing, ectatic, thin-walled vascular channels. All cases contained atypical, enlarged, degenerated fibroblasts with abundant basophilic cytoplasm, large hyperchromatic, smudged nuclei, and prominent nucleoli; these features resulted in a superficial resemblance to proliferative fasciitis. The enlarged, atypical fibroblasts stained diffusely and strongly for vimentin (15 of 15 cases) and focally for muscle-specific actin (10 of 15 cases), keratin (one of 15 cases), CD68 (10 of 15 cases), and CD34 (five of nine cases) antigens; none of the cases stained for desmin. A malignant diagnosis was considered in 43% of cases. Follow-up in 21 patients ranged from 2 to 78 months (median, 12 months). Two lesions recurred once, one recurred twice, and none metastasized; no deaths were attributable to the lesions. The clinical, histologic, and immunohistochemical features of atypical decubital fibroplasia indicate it is a unique type of pressure sore displaying degenerative and regenerative features distinct from decubitus ulcer. Its recognition by pathologists and clinicians in elderly and debilitated patients is important to avoid misdiagnosis as a sarcoma and to prevent or minimize the occurrence of decubital fibroplasia in progressively aging patient populations.  相似文献   
97.
Sclerosing cholangitis: CT findings   总被引:5,自引:0,他引:5  
The value of computed tomography (CT) in the detection of primary sclerosing cholangitis (PSC) in the intrahepatic and extrahepatic biliary systems was assessed by comparing CT scans of 20 cases of PSC with cholangiographic findings. In 16 of 19 cases of extrahepatic duct disease demonstrated with cholangiography, CT demonstrated abnormalities of the common hepatic duct, or bile duct, including duct stenosis, mural nodularity, duct dilatation, wall thickening, and mural enhancement. CT demonstrated intrahepatic disease in all 20 cases, including duct dilatation, duct stenosis, pruning, and beading. CT was superior to cholangiography in characterization of the status of the intrahepatic duct system in 11 of 20 cases. In addition, CT demonstrated extrabiliary complications of PSC in 12 cases and superimposed cholangiocarcinoma in three cases. While cholangiography remains the standard for diagnosis and follow-up of PSC, CT can provide valuable information about the extent and complications of the disease.  相似文献   
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99.
ABSTRACT Isolated congenital tricuspid valve dysplasia is a rare and potentially lethal congenital heart disease that can be easily confused with persistent pulmonary hypertension of the newborn. We describe a neonate with isolated congenital tricuspid valve dysplasia who did not respond to mechanical ventilation but improved by tolazoline. Clinicians should be aware that the initial fulminant course of this condition may be reversed by reducing the pulmonary vascular resistance, thereby allowing time for spontaneous recovery.  相似文献   
100.
Guit  GL; Shaw  PC; Ehrlich  J; Kroon  HM; Oudkerk  M 《Radiology》1985,154(2):305-306
A case of mixed connective tissue disease (MCTD) is presented in which mediastinal lymphadenopathy was the most prominent radiological finding detected by plain chest radiographs and computed tomography. Pulmonary arterial hypertension, which is a rare and often fatal complication of MCTD, also developed in this patient.  相似文献   
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