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In 86 (49.4%) of 173 patients cancer of the colon of various localizations against the background of diffuse polyposis was diagnosed, rectal involvement being noted in 50%, cancer involvement of the cecum involvement of the cecum and ascending colon--in 5.4% and 7.2% accordingly. These data made it possible to revise an existing concept of preservation of the rectum in radicalsurgery for diffuse polyposis in favour of remaining right portions of the colon.  相似文献   
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Colony-stimulating activities (CSA) are potent granulopoietic stimulators in vitro. Using clonogenic assay techniques, we analyzed the degree to which mononuclear phagocytes and T lymphocytes cooperate in the positive (production/release of CSA) and feedback (inhibition of CSA production/release) regulation of granulopoiesis. We measured the effect of lactoferrin (a putative feedback regulator of CSA production) on CSA provision in three separate assay systems wherein granulocyte colony growth of marrow cells from 22 normal volunteers was stimulated by (a) endogenous CSA-producing cells in the marrow cells suspension, (b) autologous peripheral blood leukocytes in feeder layers, and (c) medium conditioned by peripheral blood leukocytes. The CSA-producing cell populations in each assay were varied by using cell separation techniques and exposure of isolated T lymphocytes to methylprednisolone or to monoclonal antibodies to surface antigens and complement. We noted that net CSA production increased more than twofold when a small number of unstimulated T lymphocytes were added to monocyte cultures. Lactoferrin's inhibitory effect was also T lymphocyte dependent. The T lymphocytes that interact with monocytes and lactoferrin to inhibit CSA production are similar to those that augment CSA production because their activities are neither genetically restricted not glucocorticoid sensitive, and both populations express HLA-DR (Ia-like) and T3 antigens but not T4 or T8 antigens. These findings are consistent with results of our studies on the mechanism of lactoferrin's inhibitory effect with indicate that mononuclear phagocytes produce both CSA and soluble factors that stimulate T lymphocytes to produce CSA, and that lactoferrin does not suppress monocyte CSA production, but does completely suppress production or release by monocytes of those factors that stimulate T lymphocytes to produce CSA. We conclude that mononuclear phagocytes and a subset of T lymphocytes exhibit important complex interactions in the regulation of granulopoiesis.  相似文献   
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We compared transvaginal sonography, sonohysterography, and diagnostic hysteroscopy in the evaluation of abnormal uterine bleeding, Sixty-eight women 40 or older with abnormal uterine bleeding were assigned to undergo either transvaginal sonography or sonohysterography. All subjects then had diagnostic hysteroscopy and endometrial biopsy. Patients with abnormal findings underwent operative hysteroscopy or definitive therapy. Transvaginal sonography, sonohysterography, and diagnostic hysteroscopy revealed a sensitivity of 95%, 90%, and 78%, and a specificity of 65%, 83%, and 54%, respectively. The average cost for transvaginal sonography of sonohysterography was $195 and the cost for diagnostic hysteroscopy was $675. Transvaginal sonography and sonohysterography are cost-effective alternatives and more sensitive diagnostic tests than office diagnostic hysteroscopy.  相似文献   
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