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71.
目的检测骨髓增生异常综合征难治性贫血(MDS-RA)患者、慢性再生障碍性贫血患者、巨幼细胞性贫血及正常人血清乳酸脱氢酶(LDH),研究其对MDS预后判定及与再障鉴别的临床意义。方法采用国际血液学标准化委员会介绍的酶法。结果MDS-RA组与正常人组、再障组相比较血清LDH水平明显增高,差异有统计学意义(P〈0.01);再障组与正常人组相比较血清LDH水平无明显差异,差异无统计学意义(P〉0.05)巨幼细胞性贫血患者LDH水平亦明显增高。MDS.RA组中LDH明显增高组中位生存期明显短于LDH增高组,差异有统计学意义(P〈0.01)。结论血清LDH水平可作为MDS与再障鉴别诊断、MDS预后不良的指标,但尚须进一步与巨幼细胞性贫血鉴别。  相似文献   
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An immunoradiometric assay with the use of a monoclonal antibody can detect an antigenic determinant (CA125) in peripheral blood from more than 80% of patients with epithelial ovarian cancer. In this report elevated levels of CA125 were detected in serum from patients with adenocarcinomas of the fallopian tube, endometrium, and endocervix. Among patients with endometrial cancer, CA125 levels were elevated in recurrent or disseminated disease but not with tumors confined to the uterus.  相似文献   
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In mammals, calcitonin (CT) is synthesized, stored, and secreted by intrathyroidal C cells. Several reports have suggested the presence of immunoreactive CT in the pituitary gland. We have studied the rat pituitary gland using a radioimmunoassay for CT and have also found immunoreactive CT-like material. Assay of extracts of whole rat pituitary glands was performed using a radioimmunoassay for human CT, which gave identical dilution curves with synthetic human CT (hCT), synthetic rat CT (rCT), and mouse and rat thyroid extracts, but not with a variety of other pituitary and hypothalamic peptides. Immunoreactive CT (iCT) content of extracts of whole pituitary glands ranged from 6 to 72 pg/mg wet weight of tissue (60-840 pg/whole pituitary gland), whereas iCT was not measureable (less than 5 pg/mg tissue) in similar extracts of hypothalamus and cerebral cortex. Gel filtration studies of pituitary extracts showed a peak of iCT, which eluted with 125I-rCT and diluted in parallel with rCT. To investigate whether the pituitary iCT was related to pro-opiomelanocortin, extracts of ACTH-producing AtT20/D16 cells from mice, which contain the ACTH precursor in large quantities, were examined and no iCT was found. Immunohistochemical studies of rat pituitary glands with peroxidase-antiperoxidase and immunofluorescent techniques showed positive staining for CT in cells in the pars anterior, but not in the pars intermedia of pars nervosa; this staining was not eliminated when the antiserum was absorbed with CT under conditions that completely obliterated staining of rat thyroid glands. Double staining demonstrated essentially two distinct populations of cells, one positive for CT and another positive for ACTH, with less than 1% of the cells positive for both ACTH and CT. Immunoreactive CT-like material was present in the pituitary glands of rats thyroparathyroidectomized 18 days before they were killed, but was diminished. Biosynthetic labeling in vitro of rat pituitary glands with 3H-leucine showed incorporation into prolactin; there was no incorporation into CT. No in vitro secretion of iCT by whole rat pituitary glands either basally or after high K+ stimulation was observed. We conclude that: (1) a substance that has certain immunologic and size characteristics of CT is present in minute amounts in the pituitary gland of rats; (2) this material is not a part of the ACTH precursor; and (3) positive immunohistochemical staining in pituitary glands may not be specific for authentic CT.  相似文献   
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Two patients in whom cutaneous necrotizing vasculitis and nephritis developed 12 to 22 hours after the intravascular injection of radiocontrast media are presented. In one patient, the fortuitous observation was made of sparing of the skin from vasculitis in an area into which xylocaine and epinephrine had been injected 4 hours prior to administration of the radiocontrast material. The possible mechanisms by which these reactions may have taken place and the potential implications are discussed.  相似文献   
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