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81.
82.
A new vital staining method with neutral red has been established where by cerebral ganglion cells can be stained in vivo .  相似文献   
83.
An 80 year old Japanese man had adenosquamous carcinoma of the gall-bladder characterized by an adenocarci-noma (AC) in the gall-bladder lumen and a squamous cell carcinoma (SCC) in the Invaded region of the liver. In the AC, the tumor cells consisted of atypical columnar epithelium with pseudostratification, mimicking gastric foveolar epithelium, while atypical signet-ting cells were scattered within the SCC. There was an abrupt transition between the AC and SCC areas. The tumor cells in the AC area were intensely positive for galactose oxidase-Schiff staining, and paradoxical concanavalin A staining revealed these tumor cells to have Class II mucins. lmmunohistochemically, the tumor cells in foveolar-type adenocarcinoma were diffusely positive for cathepsin D. Flow cytometrical analysis of DNA content showed the AC area to be diploid and the SCC area to be aneuploid. The Sphase fraction of the SCC area (46.9%) was larger than that of the AC area (19.5%). The positive rate of immunostaining for proliferating cell nuclear antigen in the SCC area (mean 50.627%) was larger than that of the AC area (mean 3.048%, P < 0.01). These resutts suggest that the AC area of this tumor, histochemically and immunohistochemically, showed gastric foveolar-type characteristics, the SCC component was squamous cell metaplasia of the preexisting AC, and that the SCC area had a greater proliferating capacity than the AC area.  相似文献   
84.
Transforming growth factor-beta (TGF-beta) is one of the cytokines which play an immunosuppressive role in an inflammatory process. To investigate the local production of TGF-beta, we evaluated the levels of TGF-beta in tuberculous pleural effusions (TBPE) and non-tuberculous benign pleural effusions (non-TBPE) by the growth inhibition assay with Mv1Lu mink lung epithelial cells. The mean level of TGF-beta in TBPE (46.1 +/- 31.5 pM; mean +/- s.d.) was higher than in non-TBPE (21.7 +/- 12.3 pM) (P < 0.05). Although the level of interferon-gamma (IFN-gamma) in TBPE measured by ELISA was significantly higher than in non-TBPE, there was no significant difference in the levels of tumour necrosis factor-alpha (TNF-alpha) measured by ELISA between these two groups. Moreover, to elucidate localization of TGF-beta in tuberculous pleurisy, immunohistochemical studies of pleura, using the rabbit polyclonal antibody Ab39 against latent TGF-beta 1 binding protein (LTBP) were performed. Results revealed that LTBP was localized in immature fibrotic areas where infiltrations of T lymphocytes and macrophages were absent. Importantly, the major sources of LTBP in these areas were thought to be mesothelial cells and fibroblasts. LTBP was not found in granulomas and mature fibrotic areas. Our data suggest that TGF-beta in tuberculous pleurisy may play important roles for regression of granulomatous inflammation and pleural fibrosis for tissue repair.  相似文献   
85.
A case of primary gastric T-cell lymphoma, which was positive for granzyme B, is reported. The patient was a 47-year-old Japanese female who complained of a dull upper abdominal pain. Radiographic and endoscopic examinations revealed an ulcerative infiltrative lesion in her stomach. Following the confirmation of a high-grade malignant lymphoma, a distal gastrectomy with regional lymph nodal dissection was performed. The histology of the gastric lesion revealed a malignant lymphoma of the diffuse pleomorphic type without lymph nodal involvement. Immunohistochemistry revealed that the tumor cells were positive for LCA, CD3, TIA-1 and granzyme B, but were negative for CD4, CD8, CD56, CD30, L-26, EMA, TCR alpha/beta and TCR gamma/delta. Because the tumor cells showed T cell nature with cytotoxic activity proved by TIA-1 and granzyme B, and without evidence of further maturation of T cell, a malignant lymphoma originating from extrathymic-derived T cells was suggested.  相似文献   
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TCR repertoire in early fetal mouse thymus   总被引:1,自引:0,他引:1  
We investigated the rearrangement and expression of TCR genesin mouse fetal thymus organ culture, a system that avoids subsequententry of hematopoietic precursor cells. The first observablerearranged TCR gene was homogeneous V2-J2, detectable as earlyas fetal day 11 (d11) in the thymic primordla. The productiveTCR was homogeneous V5-J1, first detectable in d13 thymocytes,followed by adult-type TCR (V4 and V7). Sequence analysis ofTCR revealed five types of V-J junctional sequences. In thevery early stage, a homogeneous V-J junction is generated viaa short homology sequence in the coding region (Type I), whilea short homology sequence in the P-nucleotlde rather than thecoding region is used in the following stage (Type II). In thelater embryonic stages, diverse V-J junctions are generatedby well-known mechanisms, such as P-nucleotide (Type III), N-regioninsertion (Type IV) or trimming of the coding ends (Type V).These findings suggest that the generation of homogeneous TCR (V2 and V5) in the early fetal stages is due to the intrinsicrearrangement mechanisms and is in stage specific manner.  相似文献   
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A completely infarcted lymph node is an unusual event. However, lymph node infarction should alert the pathologist to the considerable likelihood of malignant lymphoma. We report two unusual cases of acute myeloid leukemia presenting with granulocytic sarcoma at disease onset with a lymph node lesion exhibiting extensive lymph node infarction. The infarcted tissue contained numerous eosinophilic cell ghosts. There were some islands of degenerated, pyknotic medium-sized nuclei resembling lymphoblasts present in the necrotic area. By immunohistochemistry, these medium sized cells were CD3-, CD20-, CD34+, CD43+, CD45RO-, CD68-, CD79a- and myeloperoxidase+ in both cases. Differentiation of granulocytic sarcoma from malignant lymphomas is important for adequate therapy. The present cases indicate that granulocytic sarcoma should be added to the list of differential diagnoses for lymph node infarction.  相似文献   
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