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71.
A case of lymphomatoid granulomatosis (LYG) involving the lungs, skin, stomach, and possibly the left kidney in a 60-year-old man is presented. The infiltrates in the lungs, stomach, and skin showed a polymorphic appearance, and consisted predominantly of lymphocytes of mature and blastic form and of a few neutrophils, plasma cells, and histiocytes. Most lymphoid cells showed irregularly shaped nuclei and clustered dense bodies, characteristics indicative of T lymphocytes. An immunohistochemical study confirmed the T cell origin of the lymphocytes; i.e. they were positive for Leu-1, Leu-3a and la-like antigens but negative for Leu-2a antigen and the antibodies against light chains. The homogeniety of the major population of infiltrates in LYG indicates that at least some forms of LYG may be neoplastic or pre-neoplastic lymphocytic disorders which may ultimately progress to malignant lymphoma. ACTA PATHOL. JPN. 35 : 711–721, 1985.  相似文献   
72.
73.
A large tumor massively occupying the left pleural cavity had the Andings of both typical carcinoid and oncocytoma which were thought to be of bronchogenic origin. The ultrastructural observation of the tumor revealed a mixture of rod-shaped granules in addition to usual round neurosecretory ones. In the nuclei of dark cells of the oncocytoma, a latticed or hatched structure was detected. Besides two adenomas and hyperplastic foci of large acidophilic cells in the thyroid, a black adenoma and cortical adenoma in the adrenal gland, were detected. Moreover, there was an ectopic adrenal gland in the retroperitoneum. Briefly it was suggested that the bronchial carcinoid presented may be related to multiple endocrine adenomatosis.  相似文献   
74.
Platelet interactions with calcium-phosphate-coated surfaces   总被引:1,自引:0,他引:1  
Kikuchi L  Park JY  Victor C  Davies JE 《Biomaterials》2005,26(26):5285-5295
Many studies have shown that calcium-phosphate (CaP)-coated endosseous implants exhibit more peri-implant bone formation and bone contact at early healing times than uncoated implants. Since the rate of healing is influenced by blood/implant interactions and possibly the degree of blood platelet activation, the aim of this study was to determine whether the topography, microtopography, or the presence of calcium (Ca) and phosphate (PO(4)) ions in the implant surface plays a predominant role in platelet activation. We define the threshold between topography and microtopography as the limit of the scale range of platelets themselves; thus, a microtopographic surface is defined by one which exhibits features 3mum. With the help of four international collaborating laboratories, we prepared 11 titanium and CaP-modified titanium surfaces each with different (micro)topographies and interrogated these surfaces with both platelet adhesion (lactate dehydrogenase activity) and platelet activation (microparticle formation and P-selectin expression) assays. Our results show that: calcium (Ca)- and phosphate (PO(4))-containing surfaces of increasing surface microtopographical complexity exhibit increasing platelet activation; surfaces with similar surface microtopographies show similar levels of platelet activation regardless of the presence of Ca and PO(4) in the surface; and that surface microtopography is responsible for platelet activation rather than the presence of Ca and PO(4) in the surface.  相似文献   
75.
Seven metastasizing small renal cell carcinomas smaller than 30 mm in the greatest diameter were clinicopathologically studied for a better understanding of their characteristic features as compared to those of small tumors without metastases. Grayish-white infiltrating tumors in gross appearance and alveolar or solid microscopic structure consisting of granular or spindle cells and of atypical nuclei were suggestive of having metastases. Two tumors which had positive reactions to the lower nephron markers such as SB A, PNA, and/or DBA were considered to be of lower nephron origin and displayed poor prognosis. ACTA PATHOL. JPN. 37: 947–954, 1987.  相似文献   
76.
A rare case of extraskeletal mesenchymal chondrosarcoma in a 47-year-old woman is reported. The tumor was located in the soft tissue of left upper arm without any involvement of the humerus. The outer portion of the tumor was histologically composed of primitive mesenchymal cells, and the inner portion showed zones of cartilaginous differentiation. Ultrastructurally, the tumor cells in the primitive areas had a relatively small number of mitochondria, rough endoplasmic reticulum, and free polysomes, and the matrix of the tumor consisted of dense bundles of collagen fibrils. The cartilaginous cells seen in the central portion of tumor were embedded in the matrix of abundant collagen fibrils and matrix granules. They had polysomes, well-developed Golgi complexes, and ample rough endoplasmic reticulum frequently with dilatation. Clear zones adjacent to the cells were seen in the extracellular matrix. With a review of the literature, the histogenesis of this particular tumor is discussed. ACTA PATHOL. JPN. 34: 1355–1363, 1984.  相似文献   
77.
78.
A 55-year-old woman with a small focus of malignant lymphoma, 6 mm in diameter, arising within an area of reactive lymphoid hyperplasia (RLH) of the stomach is reported. The diagnosis of lymphoma was suspected by the preoperative endoscopic biopsy. This is the case of this association with an unusually small lymphoma in the early stage, in support of the view that there may be an intimate histogenetic relationship between lymphoma and RLH.  相似文献   
79.
We report a case of late recurrence of chondromyxoid fibroma (CMF) arising in a thoracic vertebra in an 11-year-old male. This was treated by curettage, and 30 years later, the patient noticed shoulder pain and leg weakness. A recurrent mass appeared at the same site in the spinous process of T6. The histologic features of the recurrent tumor were similar to those of the primary lesion. A total of 38 cases of CMF of the vertebra have been reported. Only 3 of 38 previously reported vertebral CMF recurred. Tumors recurred 2 years after operation in 2 cases, and 7 years after operation in 1 case.  相似文献   
80.
Primary ovarian angiosarcoma is extremely rare. Only 16 cases have histologicaliy been reported to date In the Ilterature. A case of angiosarcoma arising In the right ovary of a 46-year-old female is presented. Grossly, the resected right ovary was completely replaced by a solid tumor mass, which revealed multiple necrotic and/or hemorrhagic foci. This case revealed the typical histological features of angiosarcoma with sinusoldal and solid patterns of anaplastic tumor cells. Immunohlstochemically, tumor cells were strongly and diffusely positive for CD31 and CD34, in particular, along the cytoplasmic membrane of the tumor cells. Ultrastructurally, tumor cells possessed the intermediate junctions between tumor cells, discontinuous basal laminae attached to the irregularly shaped blood vessels and occasional cytoplasmic pinocytotlc vesicles. These findings confirmed the case as being one of angiosarcoma of the ovary. The patient died 9 months after surgery as a result of developed multlfocal brain metastases. A total of 17 cases reported as primary ovarian anglosarcoma, including this presented case, are clinicopathologically reviewed.  相似文献   
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