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101.
102.
In the present double-blind placebo-controlled study the effect of cisapride on functional dyspepsia was evaluated in patients with and without histological gastritis. Patients with functional dyspepsia and whose symptoms persisted after a 2 week run-in period with antacid treatment were randomized to receive cisapride (10 mg) or matching placebo three times daily for 4 weeks. Symptoms of epigastric pain, bloating, nausea, belching, early satiety and heartburn were graded on a four-point scale based on patients’ feedback and diary card recording. A global response was also formulated by the investigators. One hundred and four patients entered the study and 76 completed the trial, comprising 36 patients with histological gastritis and 40 patients without gastritis. Symptom scores in both gastritis and non-gastritis groups were significantly improved by both cisapride and placebo; however, the improvement was not statistically different between the two treatment groups. Cisapride produced a good or better global response in 58% of subjects with histological gastritis and in 53% of subjects without gastritis compared with 47% and 52%, respectively, of patients on placebo; this difference was not statistically significant. Gastric histology did not influence the effect of cisapride on the symptoms of functional dyspepsia.  相似文献   
103.
Miller  BA; Cheung  JY; Tillotson  DL; Hope  SM; Scaduto  RC Jr 《Blood》1989,73(5):1188-1194
Human cord blood progenitor-derived erythroblasts have recently been shown to respond to erythropoietin (Epo) or granulocyte-macrophage colony-stimulating factor (GM-CSF) with a transient increase in intracellular free calcium concentration [Cac]. However, the importance of [Cac] changes in mediating cell proliferation and/or differentiation is undefined. In the present study, the response of erythroid precursors at different stages of differentiation to Epo was examined. Erythroblasts were derived from adult blood erythroid progenitors (BFU- E) at day 7 or day 10 of culture. [Cac] was measured in individual Fura- 2 loaded cells with fluorescence microscopy coupled digital video imaging. The dynamic range (Rmax/Rmin) of intracellular Fura-2 was similar to that measured in free solution, suggesting insignificant amounts of intracellular Ca insensitive forms of Fura-2. Baseline [Cac] of erythroid cells calculated with an in vitro calibration method was 44 +/- 4 nmol/L and with an in vivo method was 46 +/- 4 nmol/L. Treatment of day 7 BFU-E derived erythroblasts with Epo resulted in no significant increase in [Cac]. In contrast, in more mature erythroblasts (day 10 of culture), Epo stimulated a large increase in [Cac] from 49 +/- 11 nmol/L at baseline to 279 +/- 47 nmol/L. This [Cac] increase occurred in phosphate buffered saline (PBS) containing no added calcium. The increase in [Cac] persisted for 18 minutes and was dose dependent. Day 7 and day 10 control cells treated with either insulin or media showed no significant change in [Cac] during 18 minutes of observation. Our data demonstrate that early (day 7) and late (day 10) erythroblasts display different responses to Epo, at least in terms of intracellular Ca++ fluxes. The differential [Cac] response observed in early and late erythroid precursors to growth factor stimulation suggests that [Cac] may be an important signal in cell differentiation.  相似文献   
104.
105.
Chronic myelogenous leukemia (CML) is a myeloproliferative disorder associated with the Philadelphia chromosome (Ph1) in more than 95% of these patients. The Ph1 and the resulting BCR-ABL fused genes are markers for this type of leukemia. In CML, the product of the fused BCR- ABL gene is typically a protein of approximately 2,000 amino acids termed P210 BCR-ABL. We have developed an assay for the BCR-ABL protein involving Western blotting of circulating white blood cells (WBC) with an anti-ABL monoclonal antibody that can detect P210 BCR-ABL and P145 ABL in peripheral blood cells from chronic phase Ph1-positive leukemia patients. This assay was used to analyze the BCR-ABL protein content of circulating WBC from CML patients before and after various treatments. In parallel to changes in percentages of Ph1-positive blood cells as determined by cytogenetic analyses of bone marrow samples, BCR-ABL protein expression in blood cells decreased or increased as patients entered remission or underwent relapse. Of interest, six Ph1-negative CML patients were BCR-ABL protein-positive. All except one had a rearrangement in the major breakpoint cluster region and that patient expressed P185 BCR-ABL and not P210. Our results indicate that the BCR- ABL Western blotting assay has clinical applications for both diagnosis and prospective evaluation of Ph1-positive and Ph1-negative CML patients.  相似文献   
106.
Intracellular hemoglobin S (HbS) polymerization is most likely to be the primary determinant of the clinical and biologic manifestations of sickle cell disease (SCD). Fetal hemoglobin (HbF) does not enter the HbS polymer and its intracellular expression in sickle erythrocytes inhibits polymerization. HbF levels, high at birth but decreasing thereafter, protect the newborn from the clinical manifestations of this hemoglobinopathy. We have measured the sequential changes in HbF, F reticulocytes, and F cells in the first 2 years of life in 25 children with SCD and compared the results with those obtained in 30 normal children (AA). We have also calculated HbF per F cell (F/F cell), the preferential survival of F cells versus non-F cells, as measured by the ratio F cells versus F reticulocytes (FC/FR) and polymer tendency at 40% and 70% oxygen saturation. HbF levels decreased from about 80.4% +/- 4.0% at birth to 9.2% +/- 2.9% at 24 months. During this time, we observed a regular decrease of the F reticulocytes and the F cells. The kinetics of the decline of F/F cell was comparable with the decline of HbF, rapid from birth (mean, 27.0 +/- 3.6 pg) to 12 months of age (mean, 8.5 +/- 1.5 pg) and then slower from 12 to 24 months of age (mean, 6.2 +/- 1.0 pg) in the SCD children. In the AA children, the decrease in HbF, due to changes in both numbers of F cells and F/F cell, was more precipitous, reaching steady-state levels by 10 months of age. Calculated values for mean polymer tendency in the F-cell population showed that polymerization should begin to occur at 40% oxygen saturation at about 3 months and increase progressively with age, whereas polymerization at 70% oxygen saturation would not occur until about 24 months. These values correspond to HbF levels of 50.8% +/- 10.8% and 9.2% +/- 2.9%, respectively, and F/F cell levels of 15.6 +/- 4.5 pg and 6.2 +/- 1.0 pg, respectively. In the non--F-cell population, polymerization was expected at birth at both oxygen saturation values. Three individuals had significantly greater predicted polymerization tendency than the remainder of the group because of early decreases in HbF. These individuals in particular, the remainder of the cohort, as well as other recruited newborns, will be studied prospectively to ascertain the relationship among hematologic parameters, which determine polymerization tendency and the various clinical manifestations of SCD.  相似文献   
107.
108.
本文对生理载荷条件下(正常步态、爬楼梯和日常活动的混态载倚)骨水泥髋臼假体(牛髋骨试件)的失效机制进行研究.试验中利用髋关节仿真试验机施加生理载倚,利用人工仿真关节液来模拟体内生理环境,以测试髋臼假体的生命周期.在试验中通过微CT扫描仪观测并记载破坏的进程,并在试验结束后使用显微镜进行验证.结果表明,在所有载荷条件下,骨水泥-骨的界面松解是导致假体失效的原因,在体外环境条件下界面松解发生在髋臼窝中心的后上部区域,在体内生理环境下界面松解则发生在髋臼窝的所有区域.因此.模拟人体内部生理条件的试验环境是必需的,同时也确定髋臼假体的失效来自于力学和生物学因素的共同作用.  相似文献   
109.
Wnt/β-catenin信号转导途径:大肠癌治疗的新靶点   总被引:1,自引:0,他引:1  
  相似文献   
110.
Chan  FK  Ching  JY  Hung  LC  齐文安 《英国医学杂志》2005,8(6):372-373
问题:在有阿司匹林诱发溃疡出血史的患者中,用氯毗格雷预防溃疡出血复发,是否不次于小剂量阿司匹林加埃索美拉唑?[编者按]  相似文献   
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