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101.
Summary A study of the association between the rate of proliferation of marrow fibroblast-like stromal cells (in vitro) and the rate of endosteal bone mineralization (EsMR) (in vivo) was undertaken in an osteopenic rat model. We report than 200 g male rats treated with cortisone acetate (5 mg/day for 7 days) exhibit decreases in marrow fibroblast colony-forming units (FCFU) and tetracycline-based measurements of EsMR at the level of the femoral midshaft. In cortisone-treated rats recovering for 1–3 weeks, the FCFU census and EsMR normalized during the first posttreatment week, remained at control levels after 2–3 weeks, and exhibited a relapse in the third week which signified only partial recovery. These changes were unrelated to patterns of body weight gain. The data indicate that the FCFU census can serve to index endosteal osteoblast vigor.  相似文献   
102.
We have reviewed the incidence of cisplatin-induced anaemia in patients affected with solid tumours treated with at least three courses of first-line cisplatincontaining regimens. In our experience, a low percentage (5%) of patients required transfusions of red blood cells. We think it is of the utmost importance to adopt uniform criteria in monitoring and treatment of patients at risk of developing cisplatin anaemia and to identify subsets of patients to eventually treat with erythropoietin.  相似文献   
103.
补肾中药对雄激素致不孕大鼠卵巢核仁组成区蛋白的影响   总被引:4,自引:0,他引:4  
观察补肾中药对雄激素致不孕大鼠卵巢核仁组成区蛋白的影响。用SD雌性大鼠幼仔,出生9d龄注射丙酸睾丸酮,制成雄激素致不孕大鼠(ASR)模型。80d龄灌服补肾中药水溶液两周。100d龄心脏灌注处死。以核仁组成区蛋白嗜银染色(AgNOR)和增殖细胞核杭原(PcNA)为指标,观察卵巢颗粒细胞、间质腺细胞的形态学变化。结果:补肾中药能够使ASR卵巢颗粒细胞增殖、卵泡发育。治疗组的AgNOR和PcNA计数明显高于模型组,而与对照组之间无显著差异。结论:补肾中药的这种作用可能是通过调节了下丘脑-垂体-卵巢性腺功能的结果,从而促使卵巢颗粒细胞发育、卵泡成熟。  相似文献   
104.
Summary The Southwest Oncology Group (SWOG) studied the response rate and toxicity of merbarone (1,000 mg/m2 IV continuous infusion days 1–5, q 21 days) in patients with advanced metastatic renal cell carcinoma. Among 36 eligible patients, there was one partial response for a response rate of 3% (95% C.I. 0.1–15%). There were no mixed responses. There were no treatment related deaths or adverse drug reactions. Significant anemia, diarrhea, and hypercalcemia were observed. Mild to moderate degrees of malaise/fatigue/lethargy, dizziness/vertigo, hyperglycemia, creatinine increase, nausea, vomiting, weight loss, pedal edema, dyspnea, and granulocytopenia were noted. Merbarone does not have significant activity as a single agent in advanced renal cell carcinoma.  相似文献   
105.
Desmoplastic malignant melanoma (DMM) is a rare variant of spindle cell melanoma. We report a case of DMM of the forehead secondarily involving the orbit. The diagnosis was based on light microscopic features, including prominent peripheral cell nest formation and spindle cell fascicles in densely collagenous stroma. Immunohistochemical studies showed strong uniform staining for S100 antigen throughout the tumour. It was negative for HMB 45, smooth muscle actin, desmin, cytokeratins and Type IV collagen. Electron microscopy showed neither melanosomes nor myelin figures. The clinical and histological characteristics of desmoplastic malignant melanoma, and its differential diagnosis of malignant schwannoma, are discussed. DMM has a poor prognosis, since it tends to invade deeply, recur locally and metastasise readily.  相似文献   
106.
大气中不同粒径颗粒物诱导人羊膜FL细胞UDS的研究   总被引:3,自引:0,他引:3  
本研究以诱导人羊膜细胞UDS为指标,对太原市大气不同粒径的颗粒物提取液进行了致突变性检验,结果表明,不同粒径颗粒物的提取液均可产生一定的遗传毒性,尤以3.3μm以下的颗粒物的遗传毒性较强。  相似文献   
107.
饮用淦河温泉下游河水对儿童健康的影响   总被引:2,自引:0,他引:2  
长期饮用淦河温泉下游河水可使儿童头发中硒与硫的含量高出正常(指饮用自来水的)儿童约4倍,呈现高硫高硒体征,此体征儿童心率较慢,窦性心率不齐者增多,心房去极电位升高,心室去极和复极电位下降,S-T段移位例数和移位幅度均增加,心电图中的这些变化均在允许范围之内,但有些已接近病理边缘。红细胞数和血红蛋白量均略低于正常儿童。  相似文献   
108.
In human Y-79 retinoblastoma cells corticotropin-releasing hormone (CRH) produces a marked and rapid increase of adenylate cyclase activity. The concentration of the peptide producing half-maximal stimulation is 60 nM. The effect of CRH is significantly antagonized by the specific CRH receptor antagonist alpha-helical CHR 9-41 and is mimicked by sauvagine and urotensin I, two peptides displaying sequence homology with CRH. These results demonstrate the presence of functional CRH receptors in human Y-79 retinoblastoma cells and suggest that this cell line may be a suitable model in which to study the action of CRH on human retinal cell function.  相似文献   
109.
Abstract: Polycythaemia vera (PV) is a myeloproliferative disorder characterized by haematopoietic progenitor cells being hypersensitive to cytokines such as erythropoietin, interleukin-3, stem cell factor and insulin-like growth factor 1, which results in an increased production of mature blood cells. The pathogenetic cellular mechanism(s) behind this hypersensitivity to cytokines is unknown, but the number of cytokine receptors and the interaction between ligand and receptor are normal in PV. Interest has therefore focused on post-receptor mechanism(s). Haematopoietic cell phosphatase (HCP) is an intracellular tyrosine phosphatase that has been demonstrated to regulate proliferative signals negatively induced by the cytokines mentioned above. Moreover, motheaten mice that genetically lack HCP have an increased amount of erythroid progenitors that are hypersensitive to Epo, and patients with familial polycythaemia have been shown to exhibit a mutation of the Epo receptor gene that includes the docking site for HCP. We therefore studied mRNA expression of HCP in pure populations of CD34+ cells, granulocytes, platelets and lymphocytes from patients with PV, chronic myeloid leukaemia (CML) or essential thrombocythemia (ET), as well as healthy controls. Using a polymerase chain reaction analysis employing specific primers for HCP, we failed to detect any abnormalities of HCP expression in PV in any of the cell populations that were examined. Moreover, HCP mRNA expression was similar in ET and CML compared to controls. Finally, Western blot analysis revealed a normal HCP protein content in PV granulocytes and platelets. We therefore conclude that neither an impaired expression of the HCP gene nor a defect in HCP protein synthesis is present in PV, and does not seem to play a role in the aetiology of this disorder.  相似文献   
110.
应用单链构象多态性分析多聚酶链反应EB染色法(PCR-SSCP-EB)对40例肺癌组织标本的P53基因序列5~8外显子突变进行分析,同时应用PCR方法检测上述标本及18例肺良性疾病组织标本中HPV16、18型DNA相关序列,旨在分析二者在肺鳞癌发病中的作用及相互关系,并就肺鳞癌与P53基因结构和功能异常的关系进行初步探讨。  相似文献   
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