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21.
Monoclonal antibody LICR -LON- M18 identifies the immunodominant oligosaccharide sequence of the I(Ma) blood-group antigen: Gal beta 1----4GlcNAc beta 1----6--. In primary breast cancers this structure is almost totally cryptic, due to "masking" by sialic acid, but can be revealed by digestion with the specific glycosidase neuraminidase. Following desialylation, light microscopic immunohistochemical examination has revealed the epitope identified by LICR -LON- M18 to be heterogeneously distributed throughout the population of breast carcinoma cells. These tumor cells express the antigen as both a cytoplasmic and a surface membrane determinant. In the normal human breast, this structure is expressed exclusively along the luminal plasma membranes of the duct and alveolar littoral epithelial cells. Desialylation of tissue sections of normal resting and lactating breast epithelium with neuraminidase virtually abolishes the heterogeneous intercellular distribution of the I(Ma) determinant. In desialylated nonneoplastic breast tissues, the expression of this antigen is observed within the cytoplasm of some myoepithelial cells, but not in the littoral epithelial cells. The expression of the I(Ma) antigen by neoplastic and normal breast epithelial cells has also been compared with that of the oligosaccharide sequence Gal beta 1----3GalNAc. This structure, recognized by peanut agglutinin, forms the dominant portion of the Thomsen-Friedenreich antigen. With respect to normal and lactating breast epithelial cells, both oligosaccharide structures are sialylated and appear to be similarly misprocessed by breast carcinomas. The masking of surface carbohydrate determinants and the faulty processing of structures usually expressed on the surface of non-neoplastic breast epithelial cells may be important phenomena in the pathobiology of breast carcinomas. 相似文献
22.
Radioprotective efficacy and acute toxicity of 5-androstenediol after subcutaneous or oral administration in mice 总被引:3,自引:0,他引:3
Whitnall MH Wilhelmsen CL McKinney L Miner V Seed TM Jackson WE 《Immunopharmacology and immunotoxicology》2002,24(4):595-626
We previously showed that one subcutaneous (sc) injection of 5-androstene-3beta,17beta-diol (AED) stimulated the innate immune system in mice and prevented mortality due to hemopoietic suppression after whole-body ionizing irradiation with gamma rays. In the present study, we tested whether there was any significant toxicity in mice that might hinder development of this steroid for human use. There were no indications of toxicity in chemical analyses of serum after sc doses as high as 4000 mg/kg. At this dose, 2 of 54 mice died when given AED alone. When 4800 mg/kg was given orally, no deaths resulted. The only adverse findings attributed to AED administration were 1) a moderate elevation of granulocytes in abdominal organs and fat after sc injections of 320 mg/kg; and 2) occasional wasting of skin over the injection site in female B6D2F1 but not male C3H/HeN mice. Significant weight loss (6%) was observed after sc injections of 320 mg/kg but not 160 or 80 mg/kg. When male C3H/HeN mice were injected sc with AED at doses of 0-200 mg/kg 24 h before whole body gamma-irradiation (9 Gy), a significant improvement in survival was observed at doses as low as 5 mg/kg. Oral administration of AED produced significant survival enhancement at a dose of 1600 mg/kg. We conclude that the radioprotective efficacy of AED is accompanied by low toxicity.Androst-5-ene-3 beta, 17 beta-diol; Ionizing radiation; Experimental radiation injuries; Toxicity; Clinical chemistry; Histopathology 相似文献
23.
本文报道一例用病理组织学、免疫组织化学和免疫电镜综合确诊的多克隆性IBL样T细胞性淋巴瘤。讨论了这三种病理研究手段综合应用在本例诊断中的意义。指出免疫电镜在确定阳性反应细胞的细微形态上较光镜有明显优越性。 相似文献
24.
目的 观察家兔面神经急性损伤后髓鞘和轴索的组织病理变化。方法 用丝线结扎茎乳孔以外的面神经总干 ,观察结扎后 1天、3天及 5天面神经的组织病理改变。结果 家兔面神经受损后 ,先后在髓鞘和轴索出现轻重不等、程度不同的形态学改变。结论 结扎家兔面神经后 ,其髓鞘及轴索会出现相应的病理改变 ,且随着结扎天数的增加 ,面神经损伤亦呈加重的趋势 相似文献
25.
Akash Pramod Sali Priyal Motghare Munita Bal Neha Mittal Swapnil Rane Shubhada Kane Asawari Patil 《Head and neck pathology》2021,15(2):544
Parathyroid carcinoma (PC) is a rare malignancy that poses a diagnostic challenge on histologic examination. We analyzed various clinicopathologic features of PC. Pathology reports and slides were reviewed to evaluate the diagnostic histopathologic features of archived cases of PC from the years of 2004–2018. The study cohort comprised twenty cases of PC. The median age was 49 years (range 21–73 years) with equal gender distribution (M:F = 1:1). Most patients presented with symptoms of hypercalcemia (n = 7, 54%). Serum calcium and serum parathyroid hormone were elevated in all but one patient. The right inferior parathyroid was commonly involved (n = 8/14, 57%). The mean tumor size was 2.4 cm (range 0.8–3.5 cm). On frozen section examination, PC was diagnosed in 8 out of 9 cases. Vascular (n = 19/20, 95%) and soft tissue invasion (n = 10/20, 50%) were the most common characteristic histologic findings. Capsular invasion was identified in all cases. Perineural invasion or metastasis at presentation was absent in all cases. Other histological features noted were intratumoral fibrous bands (70%), nodular growth pattern (70%), moderate nuclear atypia (30%), prominent nucleoli (20%), and necrosis (20%). Regional lymph nodes were negative for metastatic disease in all cases (n = 10). Eight out of 16 patients received adjuvant radiotherapy. Follow-up was available in 16 cases (median 21.5 months). Two patients died of disease. Vascular and soft tissue invasion are the most common diagnostic histologic features of PC. Capsular invasion is important to distinguish PC from its benign counterparts. Intraoperative frozen section examination can be used for accurate diagnosis and surgical management. 相似文献
26.
P. Lylyk F. Viñuela H. V. Vinters J. Dion J. Bentson G. Duckwiler T. Lin 《Neuroradiology》1990,32(4):304-310
Summary The internal carotid artery system in swine has a special anatomic configuration similar to a brain arterial-arterial malformation. The internal carotid artery breaks up into a multitude of fine channels (rete mirabile) situated at the base of the skull on the side of the hypophysis. This anatomic arterial model was used to analyze acute and chronic angiographic and histological changes after occlusion of the rete mirabile with I) avitene, II) avitene, and 50% ethanol, III) avitene, 30% ethanol and Polyvinyl alcohol, IV) avitene 50% ethanol and Polyvinyl alcohol, V) IBCA and VI) silk. Histopathological changes observed in the rete mirabile six weeks following occlusion demonstrated that a mixture of avitene, 30% ethanol and Polyvinyl alcohol and IBCA produced the best anatomic results. Embolization with avitene, PVA and ethanol induced a more bland histological reaction than the one observed with IBCA. Preliminary clinical experience with this mixture is reassuring in those cases in which the AVM was surgically resected. The partially thrombosed AVM was easily depressed and compressed by the neurosurgeon allowing for satisfactory hemostasis in and around the nidus of the AVM.This paper was presented in part at the International Symposium on Cerebral Stroke, Sendai, Japan, 1987 相似文献
27.
目的 :研究炭纤维对动物大脑皮质神经细胞的影响及炭纤维在颅内的移动规律。方法 :将炭纤维细粉注入小鼠和家兔左侧大脑颞叶皮质内 ,动态观察脑组织病理学改变及炭纤维在颅内的移动。结果 :实验组 (EG)术后 1~ 5 2周 ,未发现小鼠和家兔有与炭纤维注入有关的神经病学改变 ;术后 1~ 2周 ,EG与 CG(对照组 )小鼠和家兔的脑组织病理学检查显示轻度异常改变 ,二组间差异不显著 ;术后 4~ 5 2周 ,EG、CG小鼠和家兔的脑组织未见明显的损伤性病变 ,EG可见炭纤维向脑内的正常裂隙移动和沉积。结论 :1炭纤维细粉注入动物大脑颞叶皮质后显示出良好的组织相容性 ;2注入动物脑内的炭纤维细粉崩解形成的碎屑最终可能通过淋巴途径清除。 相似文献
28.
29.
T. Buhr H. Choritz A. Georgii 《Virchows Archiv : an international journal of pathology》1992,420(6):473-478
Summary A histological study on sequential bone marrow biopsies in patients with chronic myeloid leukaemia (CML) was performed. We wished to answer the question as to whether a different content of megakaryopoiesis in the bone marrow of CML patients has a prognostic significance for the development of myelofibrosis during the course of disease. In addition, the significance of possible changes in the quantity of megakaryopoiesis in this process was assessed. In 186 patients who had no fibre increase at first diagnosis, the rate of subsequent myelofibrosis varied from 19% for the common or granulocytic subtype (CML.CT) to 40% for patients with features of megakaryocytic increase (CML.MI). No significant differences were found either in the rapidity of progression to fibrosis or in the final rate of osteomyelosclerosis. Whereas in CML.MI most patients (75%) showed an increase of fibres only, this was accompanied by an additional increase of megakaryocytes in CML.CT, changing the histological pattern from CML.CT to MI or MP, respectively. The data therefore revealed a correlation between fibre increase and subtyping of CML as suggested by the Hannover classification of chronic myeloproliferative diseases. Subtypes of CML with megakaryocytic increase could be shown to present a pre-myelofibrotic stage of disease and may therefore be conceived as a particular pathway of acceleration. 相似文献
30.
Summary Muscle biopsies of two patients originally reported in the Göttingen family by Becker (1962) that formed the basis of separating a benign X-linked muscular dystrophy from the rapidly progressive Duchenne-type X-linked muscular dystrophy, revealed mild pathological changes in the younger patient and more advanced in the older one, consisting of increased spectra of fiber diameters, endomysial fibrosis, angulated fibers, pyknotic nuclear clumps and small groups of atrophic fibers. Essentially, both biopsies showed the same changes, but of different severity, possibly due to the differences in age and muscle biopsy sites. These changes were regarded myopathic, but a neurogenic component was suggested. Our observations accord well with those of a larger series (Bradley et al., 1978) where both electromyography and histopathology revealed a mixed myopathic-neurogenic pattern in patients with Becker-type dystrophy. Differential diagnostic aspects encompass Duchenne's muscular dystrophy, the other hereditary dystrophies and X-linked proximal spinal muscular atrophies. The precise nature of Becker-type muscular dystrophy requires morphological data on peripheral nerves, spinal roots and spinal cord anterior horn cells as well as sequential biopsy analysis to substantiate the primary site of pathology. However, on the basis of available data, it seems reasonable to suggest that the early changes of degeneration/regeneration which are accompanied by a markedly elevated CPK eventuate in the histopathologic and electromyographic patterns illustrated in these two patients with Beckertype dystrophy.These studies have in part been supported by a grant from The Volkswagen-Stiftung (HHG). Parts of this paper have been presented at the Neurochemical Group Symposium, Bath University, March 30, 1977, and at the Annual Meeting of the German Society of Neuropathology, Tübingen University, October 17–19, 1977 相似文献