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91.
A case of angioimmunoblastic lymphadenopathy with dysproteinemia (AILD) which showed widespread involvement of the gastrointestinal tract is reported. A lymph node biopsy specimen showed the characteristic histological features of AILD. During the progression of the illness, lymphomatous lesions developed in the gastrointestinal tract, complicated by cytomegalovirus infection. A double immunoenzymatic study using a combination of Ki-67 antibody and antibodies against surface antigens demonstrated that CD3+, CD4+, and/or T-cell receptor (TCR) beta+ cells were predominant (67-68%) among the population of proliferating Ki-67% cells, rather than CD8+ or CD22+ cells. Clonal rearrangement of the TCR beta chain gene was also detected. These findings provide further evidence for the neoplastic nature of lesions of this type, and the diagnosis of peripheral T-cell lymphoma.  相似文献   
92.
93.
Monocytoid B-cell lymphoma: a study of 36 cases   总被引:3,自引:0,他引:3  
We have studied 36 cases of monocytoid B-cell lymphoma (MBCL). We confirm the predilection for females (30 of 36; ratio, five women to one man). The median age was 65 years (range, 29 to 85 years). Monocytoid B-cell lymphoma characteristically involves peripheral lymph nodes (30 of 36) with a propensity for paraparotid or intraparotid nodes. Salivary glands were affected in five patients. Other extranodal sites of involvement included breast, thyroid, stomach, and soft tissue of chest wall. Eight patients manifested with Sj?gren's syndrome, one had systemic lupus erythematosus, one presented initially with Raynaud's phenomenon, and two had a monoclonal gammopathy. "Composite lymphomas" were encountered in seven patients. In addition, association with or progression to a higher-grade lymphoma, ie, mixed small and large cell (one) and large cell (six), was observed in seven patients and was associated with a more aggressive behavior of the lymphoma. Immunohistochemical studies performed on biopsy sections from 20 patients confirmed the B-cell nature of MBCL. An average reactivity of less than 10% of the monocytoid B cells with the proliferation marker Ki-67 was demonstrated, in keeping with the indolent behavior of MBCL. Despite our observation of follicular lymphomas frequently accompanying MBCL, the t(14;18) chromosomal translocation does not appear to play a pathogenetic role for MBCL, as determined by molecular studies for the t(14;18) chromosomal translocation and immunologic studies for the BCL2 protein. Our observations also provide support for the proposal that there is an overlap between MBCL and "MALT lymphomas" (those arising from mucosa-associated lymphoid tissue).  相似文献   
94.
A rare case of malignant lymphoma of the adrenal gland in a 68-year-old male is reported. Autopsy revealed bilateral and symmetrical adrenal tumors (lt: 54 g, rt: 39 g) and almost complete effacement of both adrenal glands, while no tumors were present in other organs or systemic lymph nodes. Both adrenal tumors histologically presented a picture of diffuse malignant lymphoma of mixed cell type. Microscopic involvement in both lungs, spleen, liver, lymph node, bone marrow and both kidneys was found. Immunohistochemically, the positive reactions shown by the lymphoma cells were of B cell type, i.e., observed using antibodies to the leukocyte common antigens, MB-1, LN-1, LN-2 and LN-3, but not by anti-factor VIII-related antigen or MT-1. Examination of peripheral blood obtained just before the patient died showed the presence of 18% atypical cells. This lymphoma was considered to have transformed to a leukemic phase, at least at the end stage. To the author's knowledge, this is the second case of primary adrenal lymphoma to be reported in Japan, and the first case showing formation of bilateral and symmetrical tumors.  相似文献   
95.
Summary An immunohistochemical study of 63 cases of Hodgkin's disease was undertaken using formalin-fixed paraffin embedded tissue sections. The antibodies used were against L26, LN-1, LN-2, EMA (epithelial membrane antigen), Leu-M1, Vimentin, UCHL-1, S-100, and lysozyme. Hodgkin's disease could be divided into three groups: the first group was LN-1+/L26+/vimentin-, the second LN-1-/L26+/vimentin+, and the third LN-1-/L26-/vimentin+). Sixteen cases of follicular lymphomas were also examined and were all positive for LN-1 and L26 and negative for vimentin. Thus the vimentin negativity of the first group, including 7 nodular lymphocyte-predominant cases, gives further evidence of their germinal center B-cell origin. Since vimentin is expressed mainly in the immature stage of B-lymphocytes, the second group of Hodgkin's disease may represent immature B-cell Hodgkin's disease. In the third group, vimentin was present in Reed-Sternberg's (RS) and Hodgkin's (H) cells in 45 of the 48 cases (92.5%). In none of 48 cases were these cells positive for S-100 or lysozyme, but strong vimentin-positivity still suggested monocytic or histiocytic origin. The results of our study suggest, at least, divergent origin of RS's and H's cells.  相似文献   
96.
The superior spatial resolution obtained with parallel-beam microradiography over conventional contact microradiography has allowed us to image microstructural features of dental hard tissue not previously reported. Our efforts to extend these techniques to provide a real-time capability for viewing in situ demineralization and remineralization effects, at and below the 1-micron level, have resulted in an instrument with several novel and unique features. Using a synchrotron radiation source of x rays and diffraction image magnification, we are now able to change magnification at will (x-ray zoom lens). In addition, the energy range over which the instrument operates gives one considerable flexibility in optimizing image contrast. The techniques of parallel-beam microradiography, and diffraction image magnification are applicable to problems in many other areas of science. Using examples within dental research, the uniqueness and versatility of these new techniques are discussed.  相似文献   
97.
98.
Coexistence of corticotropin releasing factor and neurotensin and also of substance P and somatostatin was demonstrated in the lateral bed nucleus of the stria terminalis and the central amygdaloid nucleus of the rat, by means of a light microscopic mirror method or immunofluorescent double staining. Using the former technique, a major proportion of corticotropin releasing factor-like immunoreactive cells were found to display neurotensin-like immunoreactivity in the dorsal subdivision of the lateral bed nucleus of the stria terminalis and the lateral subdivision of the central amygdaloid nucleus. On the other hand, the immunofluorescent method showed that a significant number of neurons with both substance P- and somatostatin-like immunoreactivity were located in the ventral subdivision of the lateral bed nucleus of the stria terminalis and the medial subdivision of the central amygdaloid nucleus. Distribution patterns of such co-localized peptides may indicate that there are morphological and biochemical similarities between the dorsal subdivision of the lateral bed nucleus of the stria terminalis and the lateral subdivision of the central amygdaloid nucleus, as well as between the ventral subdivision of the lateral bed nucleus of the stria terminalis and the medial subdivision of the central amygdaloid nucleus. Previous studies have demonstrated that peptide-containing neurons in the lateral bed nucleus of the stria terminalis and central amygdaloid nucleus, such as corticotropin releasing factor-, neurotensin-, substance P- and somatostatin-like immunoreactive cells, project to the lower brainstem. The results of the present study suggest that corticotropin releasing factor/neurotensin and substance P/somatostatin neurons may be part of the lateral bed nucleus of the stria terminalis/central amygdaloid nucleus-lower brainstem pathways.  相似文献   
99.
100.
A morphological study of parafollicular cells in the thyroid gland and parathyroid gland of the house shrew (Suncus murinus) was made. The results indicated that (1) there were two pairs of parathyroid glands which were located in the upper part of the house shrew thyroid gland, (2) the volumes of the house shrew parathyroid glands ranged from 0.014 to 0.079 mm3, (3) the number of parafollicular cells along the follicles was largest in the upper part of the thyroid lobe, while no parafollicular cells were present in the isthmus, and (4) there were about 20 parafollicular cells per 100 follicular cells and 1.519 parafollicular cells per follicle. The number of parafollicular cells per 100 follicular cells was thus about 5 times larger than that in rats and the number of parafollicular cells per follicle about 2.5 times larger than that in rats.  相似文献   
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