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11.
A genomic subtraction between a pandemic Vibrio parahaemolyticus and a nonpandemic strain that seemed to be clonally related was performed. A subtractive DNA fragment was identified to be a part of a 16-kbp insertion sequence which was present in almost all pandemic strains but not in nonpandemic strains tested.  相似文献   
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The spectrum of renal neoplasms has expanded in recent years. Although most of the work taking place in this field has concerned malignant neoplasms of the kidney, there have been significant improvements in our knowledge of benign renal tumors and tumor-like lesions, especially in renal cell adenoma, renal oncocytoma, and renal angiomyolipoma. Awareness and knowledge of these benign lesions is important because they are often included in the differential diagnoses of malignant tumors, with which they may be confused both clinically and pathologically. The authors review the topic of benign renal neoplasms and tumor-like lesions that occur in adults, emphasizing some of the newly described aspects of these lesions.  相似文献   
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We report ribosome-lamella complexes (RLC) in cancer cells of transitional cell carcinoma (TCC) of the prostate in a 52-year-old Caucasian man. Histopathologically, cancer cells were proliferated in various-sized nests, mostly associated with central necrosis. Some invaded into the surrounding normal glandular space and the stroma, with occasional lymphatic invasion. Fine structural study of cancer cells revealed that cross-sectioned RLC as well as densely aggregated ribosomes were detected in their cytoplasm, situated close to, but not directly connected with, dilated rough endoplasmic reticulum. These were composed of a concentric alternative arrangement of both lamellae and ribosomes. In the central and surrounding parts of the RLC, ribosomes were observed, revealing a smooth transition to the ribosomal component of RLC in size and shape. The presence of both RLC and dense aggregation of ribosomes close to the rough endoplasmic reticulum suggests that their functions might be related to specific or aberrant protein synthesis under unknown conditions. Although RLC have been often reported in hematopoietic malignancies, their occurrence in the malignant epithelial component has been only reported in a case of pulmonary adenocarcinoma. This is the first report of RLC in TCC in the literature.  相似文献   
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Rigor and resistance to stretch in vertebrate smooth muscle   总被引:2,自引:0,他引:2  
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We report the case of a patient with three synchronous but histologically different primary renal tumors that were all in the same kidney. Two tumors were different subtypes of renal cell carcinoma (RCC), and the third was a variant form of angiomyolipoma. The patient was a 62-year-old man who was receiving antihypertensive drugs and came to our hospital for a regular check-up. Ultrasonography performed during the visit revealed a left renal mass, but the patient had no related symptoms. Subsequent computed tomography revealed two round, high-density masses, one in the mid-portion and the other in the lower pole of the left kidney, and multiple cysts in the right kidney and the liver. The mass in the mid-portion measured 3.3 x 3.0 x 2.8 cm, and the mass in the lower pole measured 1.7 x 1.1 x 0.9 cm. A left radical nephrectomy was performed. On gross examination, an additional ovoid nodule (0.6 cm in the greatest dimension) was found in the lower pole. Microscopically, the largest tumor consisted of a broad alveolar arrangement of large round cells with abundant eosinophilic or clear cytoplasm, distinct cell borders, and perinuclear halos, features consistent with chromophobe RCC. The smallest tumor was a conventional (clear-cell) RCC. The third tumor was composed solely of atypical epithelioid cells with prominent nucleoli and yellowish-brown to black pigments. The tumor cells were positive for melanin (Fontana-Masson stain), the melanoma marker HMB45, vimentin, smooth-muscle actin, and the macrophage marker CD68 and were negative for cytokeratin. This tumor was considered a pigmented epithelioid type of angiomyolipoma. The histologic, histochemical, and immunohistochemical features in this case confirmed the presence of three synchronous primary tumors, a chromophobe and a clear-cell type RCC and a pigmented epithelioid angiomyolipoma, all of which were in the same kidney. This case is the first of its type reported in the literature.  相似文献   
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Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Wissenschaftliche Ergebnisse können eine Wissensquelle für kommunale Akteurinnen und Akteure der...  相似文献   
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Osteosarcomatosis   总被引:10,自引:0,他引:10  
A review of the 690 cases of osteosarcoma in the radiographic file of the Armed Forces Institute of Pathology revealed 29 cases of "osteosarcomatosis" (multiple skeletal sites of osteosarcoma). Fifteen of these patients were 18 years old and under and manifested rapidly appearing, usually symmetric, sclerotic metaphyseal lesions. The remaining 14 patients were more than 18 years old and had fewer, asymmetric sclerotic lesions. In most patients (28 of 29), a radiographically dominant skeletal tumor was seen. Pulmonary metastases occurred in the majority of patients and were detected at the same time as the bone lesions. These 29 patients were studied with regard to demographic data and skeletal distribution and radiographic appearance of their lesions. As a result of the findings, a metastatic origin from a primary dominant osteosarcoma is favored over a multifocal origin as the basis for osteosarcomatosis. Osteosarcomatosis is more commonly encountered in the mature skeleton than has been previously recognized.  相似文献   
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