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101.
Barth TF Leithäuser F Döhner H Bentz M Pawlita M Schmid U Möller P 《Virchows Archiv : an international journal of pathology》2000,436(4):357-364
In contrast to primary gastric lymphomas of B-cell type, little is known about primary gastric T-cell lymphomas. We describe
three cases with remarkably similar features: diffuse growth, epitheliotropism, medium too large cell size, high apoptotic
rates, and a CD3+, CD4+, CD8+, CD45RO+ immunophenotype. Clonal TCRγ gene rearrangement was shown in two cases. Epstein-Barr
virus infection was excluded in two cases. Taking advantage of fresh-frozen material, we analyzed two cases further, revealing
CD5–, CD16+, CD56–, CD57–, CD25+, CD30+, CD103 (αEβ7)+, bcl-2 protein+, CD95+, CD95 ligand(L)–. CD95L, however, was detected
in histiocytic and fibroblastoid by stander cells. The lymphomas expressed granzyme B, perforin, and the TIA-1 antigen in
various combinations. All three cases had a very unfavorable clinical course characterized by local recurrence and/or dissemination
to other epithelial sites, leading to death within 6–12 months after the initial diagnosis despite surgery and aggressive
antineoplastic treatment. These data suggest a novel variant of peripheral T-cell lymphoma operationally characterized as
primary gastric, apoptosis-rich, CD103+, EBV-, T-cell lymphoma co-expressing CD4, CD8, CD16 and cytotoxic molecules.
Received: 20 August 1999 / Accepted: 2 November 1999 相似文献
102.
Toshihiko Sato Kaoru Abe Akira Kurose Noriyuku Uesugi Takeshi Todorokl and Kohsuke Sasakl 《Pathology international》1997,47(2-3):179-182
The amplification and overexpression of the c- erbB -2 gene are considered to be Implicated In the process of carcincogenesis of a variety of human tumors. The amplification and overexpression of c- erbB -2 were investigated in 48 surgically resected human gastric cancers by means of fluorescence In situ hybridization and immunohistochemistry. DNA ploidy was determined by flow cytometry. The c- erbB -2 amplification was demonstrated as a cluster of signals, suggesting homogeneously staining region (HSR), in three tumors (6.3%) accompanied by the overexpression of its protein. Such overexpression was detected In another tumor without amplification of the c- erbB -2 gene. All tumors with amplification and overexpression of c- erbB -2 were differentiated adenocarcinoma histologically, but only 10.3 and 13.8% of differentiated carcinomas showed amplification and over-expression of the c- erbB -2 gene, respectively. There was no relationship between the amplification and overexpression of c- erbB -2 and the depth of tumor invaslon and lymph node Involvement. Three of four cases with overexpression of c- erbB -2 were classified Into DNA aneupldd tumor. 相似文献
103.
目的:通过对食管和贲门癌原发病灶和淋巴结转移病灶肿瘤抑制基因p53变化规律的研究,加深对食管和贲门癌转移发生的分子学基础的了解。方法:采用组织病理学和免疫组织化学(ABC)方法,对31例手术切除的食管和贲门癌原发病灶和转移病灶肿瘤抑制基因p53蛋白聚集进行比较研究。结果:31例手术标本中,病理检查发现24例食管鳞状细胞癌,7例为贲门腺癌。研究表明:24例食管原发和转移鳞癌中,11例原发和转移病灶中均出现p53蛋白聚集的变化,原发和转移病灶的一致性变化发生率为61%(11/18);在6例原发病灶p53免疫组化阴性患者中,其淋巴结转移病灶也同时出现免疫阴性反应。在7例胃贲门腺癌中,3例原发和转移病灶同时出现p53免疫阳性表达的一致率为50%(3/6);1例原发病灶p53免疫组化阴性患者,其淋巴结转移病灶也出现阴性反应。结论:肿瘤抑制基因p53在食管和贲门癌癌变和转移中起一定的作用。可能是食管和贲门癌侵袭与转移过程中值得重视的生物学指标之一。 相似文献
104.
Moo -Yeol Lee Hyo -Weon Bang In -Ja Lim Dae -Yong Uhm Sang -Don Rhee 《Pflügers Archiv : European journal of physiology》1994,429(1):150-152
Large conductance Ca2+-activated K+ channel was identified and studied in excised inside-out membrane patches of freshly dispersed smooth muscle cells from rabbit
gastric antrum. The current-voltage relationship of the single channel was linear from -80 to +80 mV of pipette voltage in
which single channel conductance was 249±17.8 pS (n=19) in symmetrical concentration of K+ (145mM) across the patch. Activity of the channel (NPo) depended not only on cytoplasmic calcium concentration but also on
membrane potential. MgATP increased NPo in a dose-dependent manner and Mg2+ was prerequisite for the effect. Okadaic acid (l00nM), inhibitor of protein phosphatases, increased NPo further in the presence
of MgATP. Therefore, it would be concluded that activity of the calcium-activated K+ channel in gastric smooth muscle cells was controlled by phosphorylation state of the channel protein and the state is further
modulated by membrane-delimited protein kinase and protein phosphatase activities. 相似文献
105.
本文在查阅了资料后就胃后动脉以下几方面进行综述。1.胃后动脉的起源、出现率、类型;起源于脾动脉者最多,占78%;出现率为62%~88%;绝大部分为一支类型,占75.44~92%。2.外径、长度、毗邻;外径在1.53~3mm之间;长度为2.2~8.1cm;90%的与胃后静脉伴行。3.行径、供血区:在脾动脉上缘发出后,在网膜囊后壁腹膜外向上方走行,经胃膈韧带内最后进入贲门侧的胃底部,并供应该区的血液。 相似文献
106.
107.
108.
Kanji Ohiwa Takayuki Harada Shigeru Morikawa Teruhisa Nakamura 《Pathology international》1994,44(8):635-644
The distribution of carcinoembryonic antigen (CEA) in human gastric adenocarcinoma cell lines (HPE-GAC-3 cells and HPE-GAC-2 cells) was determined immunohistochemically by indirect peroxidase-labeled antibody method at the light and electron microscopic levels. In GAC-3 cells that proliferated as non-adherent single cells, CEA was located in the perinuclear spaces, the endoplasmic reticulum, Golgi apparatus, vesicles, multivesicular body (MVB) and entire plasma membrane. Membrane CEA was shown to be internalized into MVB in GAC-3 cells. In GAC-2 cells that form an acinus, CEA was predominantly present along the microvilli of the lumina) surface and in glycocalyceal bodies, the vesicles which bud from the microvilli into the lumen. These results suggest that in poorly differentiated cancer cells CEA is transported over the entire cell surface, retained on the membrane and accumulated Into the cell by way of the MVB, but in well differentiated cancer cells the newly synthesized CEA is rapidly and predominantly transported to the luminal surface and rapidly released from the membrane into the lumen by way of the glycocalyceal body. 相似文献
109.
胃粘膜相关淋巴组织型淋巴瘤形态学研究 总被引:12,自引:5,他引:12
目的:研究胃粘膜相关淋巴细胞(MALT)型淋巴瘤及共与胃粘膜套细胞淋巴瘤和滤泡性淋巴瘤的鉴别诊断。方法:应用HE染色和免疫组化ABC法检测胃MALT型淋巴瘤,内镜作幽门螺杆菌培养基尿素试验检测HP感染。结果:31例胃MALT型淋巴瘤中低度恶性27例,高度恶性4例。细胞类型以CCL型最常见。免疫表型以IgM为主,缺乏IgD,31例中28例有HP感染(占90.52%),结论:(1)低恶MALT型淋巴瘤 相似文献
110.