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11.
Pancreatoblastoma or infantile pancreatic carcinoma is a rare pancreatic tumor with distinct acinar and squamoid cell differentiation that generally affects infants and young children. Ultrasound and CT scan may be useful but preoperative diagnosis is often quite difficult. The outcome is generally favourable. A such case of 10 years old boy with an abdominal mass is being presented.  相似文献   
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The role of calcium ions (Ca2+) in the cytotoxic activity of the dengue type 2 virus (DV)-induced macrophage (M phi) cytotoxin (CF2) was investigated in the present study. The findings show that CF2 prepared in Ca(2+)-free medium had no cytotoxic activity on normal mouse spleen cells suspended in Ca(2+)-free medium but killed the cells suspended in the medium with Ca2+. Substitution with calcium chloride restored the cytotoxic activity of CF2 the optimal dose being 10(-4) M concentration. CF2 induced an influx of Ca2+, as assayed by uptake of radiolabelled calcium chloride (45Ca), in the susceptible target cells, viz. M phi and T lymphocytes. The cytotoxic activity of CF2 as well as the CF2-induced influx of 45Ca was inhibited by treatment of the target cell with the calcium channel blocking drugs verapamil and nifedipine. Thus, the presence of Ca2+ is obligatory for the cytotoxic activity of CF2 and cell death is associated with increased intracellular Ca2+.  相似文献   
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Study on the anatomical dimensions of the human sigmoid colon   总被引:4,自引:0,他引:4  
Although the sigmoid colon is commonly afflicted with disease, studies on its anatomical dimensions are scarce. It is suspected that dimensions of the sigmoid colon change with age. This study documents data on the anatomical measurements of the sigmoid colon in 70 Indian subjects (51 live and 19 cadavers). Seven parameters of sigmoid colon anatomy measured included length and width of the sigmoid colon and mesocolon at specific points. Three mesocolic indices (width to length ratios) were calculated. Comparisons of measurements in the live and cadaver subjects and in the two sexes were made. The relationship of change in parameters with age was assessed. Appropriate statistical methods were used and the differences were considered significant at P < or = 0.05. The study showed wide ranging variations in the values of various measured parameters of the sigmoid colon. Seven patterns of the shape of the sigmoid loop were identified. In the commonest pattern the sigmoid mesocolon was vertically longer than wide (dolichomesocolic), the sigmoid loop having its maximum convexity located just a little proximal to the apex. Patterns where the width of the mesocolon was greater than the vertical length (brachymesocolic) were also observed. The gender analysis showed that the sigmoid mesocolon of the female was brachymesocolic (wider than long), whereas that of the male was dolichomesocolic (longer than wide). This might explain the higher incidence of sigmoid volvulus in the male. This study also showed that the measurements of the sigmoid colon and its mesocolon do not change significantly within the age range of 16-60 years in the two sexes. Also noteworthy is the observation that in the cadaver the sigmoid colon shows considerable shrinkage, particularly of its mesocolon; consequently the data from cadaver subjects, though valuable for anthropometric use, have limitations when used for clinical applications.  相似文献   
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We describe the clinicopathological and immunohistochemical findings in five cases of sclerosing stromal tumours of ovary and compare our findings with other reported cases of this uncommon tumour and with fibromas and thecomas which they may mimic.  相似文献   
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A unique factor, human T cell hypoglycaemic factor (hTCHF), has been shown to produce hypoglycaemia during the convalescent stage in the plasma of patients with Japanese encephalitis virus (JEV) infection. The present study was undertaken to investigate the ability of T cells from fresh peripheral blood mononuclear cells (PBMC) of such patients to produce hTCHF. The PBMC, as well as the individual subpopulations, were cultured for 24 h and the culture supernatants (CS) were assayed for hypoglycaemic activity. The activity was observed in the CD8+ T cells. The hypoglycaemia in JE-confirmed patients coincided with the gradual rise in circulating glucagon level, with no significant alterations in insulin, growth hormone and cortisol levels. The hTCHF was purified by ion exchange chromatography and the purified protein was observed as a approximately 25 kDa band on SDS-PAGE. Secretory hTCHF in the sera of patients and T cell CS was present in 88% of convalescent serum samples. We conclude that during the convalescent stage of JEV infection, a unique factor, hTCHF, is secreted by activated CD8+ T cells from patients and that this is responsible for the development of hypoglycaemia.  相似文献   
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