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91.
Sutyagin PV Kalinina EE Pylaev AS 《Bulletin of experimental biology and medicine》2005,140(2):238-242
Distribution of 3H-dopamine and 3H-DAGO binding sites was studied by autoradiography on semithin sections of total preparations of rat sinoatrial node. The
relative density of 3H-dopamine and 3H-DAGO binding sites in the functional nucleus of the sinoatrial node was minimum and increased in the cranial and caudal
directions. The level of 3H-dopamine binding in the perinodal atrial myocardium was appreciably lower (22±6%), while binding of 3H-DAGO was similar (76±16%) to that in the periarterial zone of the sinoatrial node.
__________
Translated from Byulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 140, No. 8, pp. 210–214, August, 2005 相似文献
92.
Sinus histiocytosis with massive lymphadenopathy (SHML) is a rare idiopathic proliferative disorder of histiocytes with characteristic morphologic features. We describe a case of SHML occurring in a 14-yr-old black male, in whom the diagnosis was made by fine-needle aspiration of a cervical lymph node. Cytologic features included increased numbers of large histiocytes associated with a polymorphous, cellular background composed of benign lymphocytes, plasma cells, and polymorphonuclear leukocytes. Lymphophagocytosis was a prominent feature. Extranodal involvement of the larynx was documented by surgical biopsy; there was no other extranodal disease. One year after diagnosis, the patient is clinically well, with no residual lymphadenopathy. 相似文献
93.
Kyogi Ogoshi Tomoo Tajima Toshio Mitomi Kimiyoshi Tsuji 《Clinical & experimental metastasis》1996,14(3):277-281
We investigated the association between human leucocyte antigen (HLA) antigens and lymph node metastasis in 724 gastric cancer patients. Among patients who had poorly differentiated adenocarcinoma with or without HLA-DR4 antigen, lymph node metastasis was detected in 80.8 and 54.9%, respectively (relative risk (RR)=3.5, P = 0.0005, corrected P = 0.0285). It was more common in patients with a family history of cancer death (RR = 7.7). Among signet ring cell carcinoma patients with or without HLA-1152 antigen, lymph node metastasis was detected in 57.7 and 19.7%, respectively (RR =5.6, P=0.0001, corrected P=0.0086). It was more common in patients who were smokers (RR = 8.3). Our findings suggest that HLA-DR4 and HLA-1152 antigens are associated with lymph node metastasis in gastric cancer. 相似文献
94.
95.
Direct estimation of the frequency of human cytotoxic T lymphocytes and their precursors following in vitro allosensitization 总被引:2,自引:0,他引:2
Cell mediated lympholysis (CML) has been proposed as an in vitro model of the rejection process that results from transplantation of allogeneic tissue. To date, the absolute frequencies of cytotoxic T lymphocytes (CTL) and their precursors (CTL.P) have not been directly estimated in man because of technical difficulties. Through optimizing the conditions for radiometric detection of 51Cr release and the attendant improvement in CML sensitivity, direct CTL frequency estimates have been determined in peripheral blood (PBL), spleen (SPL), and lymph nodes (LNC) after in vitro allostimulation using unrelated human cells and limiting dilution assays. The mean frequency of CTL generated from PBL is 1 in 826 cells (0.121% +/- 0.101%) which, from preliminary experiments, is significantly greater than that generated from either LNC or SPL (p less than 0.05). With restimulation of primed cells on day 10, the frequency of CTL generated from PBL was increased 400%. The CTL.P frequency (0.0064% +/- 0.0050%) was approximately 5% of the corresponding CTL frequency. The CTL.P frequencies were found to be minimal estimates as both accessory "filler" cells and T cell growth factors increased the level of detection of CTL.P an average of threefold. The limiting cell dilution assay as detailed in this report should be a powerful tool for defining the cellular requirements and related factors necessary for optimal induction of a CTL response and should provide the means for determination of the immunogenetic requirements and the allospecificity of human cytotoxic lymphocytes. 相似文献
96.
L.P. RUCO A.J.H. GEARING R. PIGOTT D. POMPONI V.L. BURGIO A. CAFOLLA A. BAIOCCHINI C.D. BARONI 《Histopathology》1991,19(6):523-528
The inducible adhesion molecules mediate important functions in the lymphoid tissues. We have investigated the expression of intercellular adhesion molecule 1 (ICAM-1), endothelial leucocyte adhesion molecule 1 (ELAM-1), vascular cell adhesion molecule 1 (VCAM-1), and platelet endothelial cell adhesion molecule (PECAM/CD31), using immunocytochemistry on cryostat sections of five lymph nodes from patients with Castleman's disease of the hyaline-vascular type. All five cases were characterized by marked hyperplasia of follicular dendritic reticulum cells, which were extensively present even in the mantle zone. Hyperplastic follicular dendritic reticulum cells showed marked expression of VCAM-1, and weak expression of ICAM-1. In two cases, several dysplastic giant cells with aberrant, polyploid nuclei showed aberrant expression of ELAM-1, an endothelium-restricted molecule. Dysplastic giant cells were positive with DRC-1 (an antibody to dendritic reticulum cells), VCAM-1 and occasionally ICAM-1, were negative for the endothelial cell markers factor VIII-related antigen and CD31 and were non-proliferating (Kl-67-). Cells positive for ICAM-1 or VCAM-1 were rare in the interfollicular areas. In all cases vascular hyperplasia was prominent, but endothelial cells were poorly activated in terms of expression of inducible adhesion molecules and of HLA-DR antigens. The possibility that dysplastic follicular dendritic reticulum cells have a pathogenetic role in Castleman's disease is discussed. 相似文献
97.
Summary In 5 cases of invasive ductal and lobular carcinoma of the breast multiple epithelioid and giant cell containing granulomas were detected, localized mainly in circumferential regions, but also in the center of the carcinomas. These granulomas were interpreted as sarcoid-like stromal reactions, occurring as sarcoid-like lesions in uni- and bilateral primaries, in a recurrent tumour, and also in axillary lymph nodes. Histopathologically, these granulomas were not quite uniform, some of them corresponding to typical sarcoidosis, others showing marked proliferations of epithelioid or giant cells or containing fibrinoid exudate or necroses. The granulomas were surrounded by dense infiltrates of mononuclear cells. Tuberculosis and mycosis was excluded. There were no hints of generalized sarcoidosis. Pathogenetically, these are reactions in the tumour stroma of varying intensity, and are not caused by necroses of the tumour tissue nor by microbial infections. Such tumour-associated sarcoid-like stroma reactions are interpreted as a T-cell mediated immune response to an antigen expression of the carcinoma acting as the local trigger; in 2 cases they were connected with sarcoid-like lesions of the axillary lymph nodes. Their occurrence in bilateral carcinoma of the breast points to an immunological disposition for this special kind of host-versus-tumour response. The intensity of these changes in a recurrent tumour reflects an immunological hypersensitivity reaction.The pathogenetic and differential diagnostic aspects of epithelioid granulomas of the female breast in chronic granulomatous mastitis, panniculitis, foreign body reaction, rare infections, and in therapeutically induced sarcoidosis are described and discussed.Dedicated to Prof. Dr. K. Lennert, Kiel, in Honour of his 65th Birthday 相似文献
98.
Alberto J. Kaumann 《Naunyn-Schmiedeberg's archives of pharmacology》1986,332(4):406-409
Summary The role of sinoatrial 1- and 2-adrenoceptors mediating positive chronotropic effects of (–)-adrenaline and (–)-noradrenaline was investigated in rat right atria. Concentration effect curves for (–)-adrenaline, but not for (–)-noradrenaline, became biphasic in the presence of the 1-adrenoceptors antagonist CGP 20712 A. The curves for (–)-adrenaline in the presence of 300 nmol/l CGP 20712 A (equivalent to 1,000 times its K
B, K
B=0.3 nmol/l for 1-adrenoceptors) comprise a high-sensitivity component that saturates at 1/4 of maximum effect, and a low sensitivity component. The high-sensitivity component is blocked by the 2-adrenoceptor-selective antagonist ICI 118,551. These results are consistent with an involvement in the rat of both 1-adrenoceptors (to a major extent) and 2-adrenoceptors [only at high (–)-adrenaline concentrations] in the positive chronotropic effects of (–)-adrenaline. (–)-Noradrenaline appears to activate mostly rat sinoatrial 1-adrenoceptors. 相似文献
99.
目的 分析南通市中小学生食源性疾病流行病学特征,为有效防控中小学生食源性疾病提供科学依据。方法 收集2015—2020年南通市哨点医院就诊的中小学生食源性疾病病例信息,并采集病例粪便标本进行病原体检测,运用χ2检验比较不同学段中小学生食源性疾病病例的分布。结果 共监测中小学生食源性疾病病例1 432例。不同可疑暴露食品的分类和进食场所的病例数有统计学差异(χ2= 73.421;χ2 = 66.857,P均<0.001),可疑暴露食品主要为肉与肉制品(28.21%)和水产动物及其制品(17.86%),可疑进食场所主要为家庭(57.60%)和学校食堂(12.69%)。疑似食源性疾病暴发事件主要发生在学校食堂。共采集标本214份,检出病原体22份,总体检出率为10.28%,阳性病原体以诺如病毒(3.74%)和副溶血性弧菌(3.27%)为主。结论 需面向家庭、学校和学生开展有针对性的食品安全知识宣传,加强中小学生食源性疾病的重点食品和场所的食品安全监测和监管,最大限度地减少中小学生食源性疾病的发生。 相似文献
100.
Marni LaFleur Kim E. Reuter Michael B. Hall Hoby H. Rasoanaivo Stuart McKernan Paulo Ranaivomanana Anita Michel Marie Sylvianne Rabodoarivelo Zamin Iqbal Niaina Rakotosamimanana Simon Grandjean Lapierre 《Emerging infectious diseases》2021,27(3):977
We diagnosed tuberculosis in an illegally wild-captured pet ring-tailed lemur manifesting lethargy, anorexia, and cervical lymphadenopathy. Whole-genome sequencing confirmed the Mycobacterium tuberculosis isolate belonged to lineage 3 and harbored streptomycin resistance. We recommend reverse zoonosis prevention and determination of whether lemurs are able to maintain M. tuberculosis infection. 相似文献