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551.
Improved results of treatment of adult acute lymphoblastic leukemia   总被引:2,自引:0,他引:2  
We designed a treatment program to improve the outcome for adults with acute lymphoblastic leukemia (ALL). Treatment included a remission- induction phase followed by intensive alternating cycles of non-cross- resistant chemotherapy and prolonged oral maintenance therapy. Eighty- one consecutive previously untreated patients were entered on this study. Ninety-four percent of patients entered complete remission. A Kaplan-Meier analysis predicts that 53% +/- 9% (SEM) of patients in remission will remain free of disease at 3 years. Neither age, sex, WBC count, nor immunophenotype had a significant effect on remission duration. This program of intensive cyclical chemotherapy has improved the disease-free survival of patients with adult ALL.  相似文献   
552.
Weisberg  LJ; Shiu  DT; Conkling  PR; Shuman  MA 《Blood》1987,70(2):579-582
Factor XIII is the fibrin-stabilizing factor that covalently cross- links fibrin monomers to form a highly organized, stable fibrin clot. The plasma form of factor XIII is a heterodimer, a2b2, consisting of two a-chains and two b-chains; the intracellular form, such as in platelets and placenta, is a dimer, a2, consisting of a-chains only. The catalytic function of factor XIII, a transglutaminase, resides in the a-chain. To address questions regarding sites of synthesis of factor XIII a-chain, an EcoRI restriction fragment from the protein- coding region of the factor XIII a-chain cDNA was used as a probe for Northern blot analysis. The cDNA probe showed hybridization with a single approximately 4.0-kilobase (kb) message in poly (A)+ mRNA prepared from normal human peripheral blood monocytes and normal human liver. The results demonstrate conclusively that factor XIII a-chains are actively synthesized in circulating monocytes and in liver. To our knowledge, these data represent the first demonstration of synthesis of any blood coagulation factor in primary uncultured and unstimulated monocytes or macrophage cells.  相似文献   
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554.
Kyoizumi  S; Murray  LJ; Namikawa  R 《Blood》1993,81(6):1479-1488
A severe combined immunodeficient (SCID)-hu mouse model implanted with human fetal bone was used to assess the effects of various recombinant human (rh) hematopoietic growth factors, administered either alone or in combination, on human hematopoiesis in vivo. Treatment with rh granulocyte colony-stimulating factor (G-CSF) elicited the expansion of mature neutrophilic granulocyte populations in human marrow. Administration of rh interleukin-3 (IL-3) induced significant increases of eosinophilic granulocyte and burst-forming unit, erythrocyte (BFU-E) activity. The rhIL-6 did not cause significant changes in the subpopulations of human hematopoietic cells within the grafts, but did increase the number of colony-forming unit, granulocyte-macrophage and BFU-E. Pretreatment with rhIL-3 followed by rh erythropoietin (Epo) administration enhanced Epo-induced human erythropoiesis significantly. No synergistic effects on myelopoiesis were observed using sequential treatment with rhIL-3 followed by rhG-CSF. Instead, these factors seemed to work independently, with rhG-CSF increasing the percentage of neutrophils and rhIL-3 increasing the percentage of eosinophils. When administered simultaneously with rhEpo, rhIL-6 showed dose-dependent inhibitory effects on in vivo Epo-induced human erythropoiesis. The rhIL-6 also caused a reduction in the percentage of human neutrophils induced by rhG-CSF. These results suggest that the SCID-hu mouse provides a useful small animal model to assess the in vivo effects of hematopoietic growth factors on human hematopoiesis.  相似文献   
555.
We have recently completed a double-blind, placebo-controlled, noncrossover study, the goal of which was to determine whether cetiedil citrate (cetiedil) could affect the course of vaso-occlusive crises in sickle cell disease. Patients, who presented to the emergency room at least 4 but no more than 24 hours after the onset of a painful vasoocclusive crisis severe enough to require hospitalization, were considered candidates for the study. Each patient received either placebo or cetiedil at one of the following three dosages: 0.2, 0.3, or 0.4 mg/kg body weight. The assigned drug dosage was given as a 30 minute intravenous infusion every 8 hours for 4 consecutive days. A total of 67 patients was enrolled in the study. Cetiedil, at its highest dosage (0.4 mg/kg body weight), was found to be significantly superior to placebo both in reducing the number of painful sites present on all 4 treatment days and in shortening the total time in crisis. No serious adverse reactions were observed during the course of the study. We conclude that cetiedil, given at a dosage of 0.4 mg/kg body weight, is therapeutically advantageous for sickle cell crisis.  相似文献   
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558.
This study was undertaken to investigate body iron stores in so-called remunerated blood donors as well as to evaluate the sensitivity of hemoglobin determination in detecting iron deficiency in two populations of blood donors. The authors studied 522 male donors who were divided into three groups: Group I, first-time volunteer donors with hemoglobin levels greater than or equal to 13 g per dl; Group II, remunerated donors with hemoglobin levels greater than or equal to 13 g per dl; and Group III, remunerated donors rejected because their hemoglobin levels were less than 13 g per dl. Iron stores were evaluated with an enzyme-linked immunosorbent assay for plasma ferritin. In Group I, 4.5 percent were iron-deficient with a mean ferritin value of 55.3 ng per ml; in Group II, 59.7 percent were iron deficient with a mean ferritin level of 17.4 ng per ml, and in Group III, 82.5 percent were iron-deficient and the mean ferritin level was 8.4 ng per ml. The last values represent the highest percentage of iron deficiency and the lowest mean ferritin value thus far reported. In Group I, hemoglobin determination had a sensitivity of 95 percent in detecting iron deficiency, but in Group II had only 40 percent sensitivity. These results indicate that a more accurate and reliable test, such as a plasma or serum ferritin determination, may be necessary to detect iron deficiency in blood donors when they donate more than five times per year, particularly those who are remunerated.  相似文献   
559.
晏泽  侯文明  李洋溢 《中国临床康复》2006,10(41):162-163,I0005
对金属软组织解剖刀除皱术进行改进,为临床七处理面部深皱纹提供一种新的微创、安全、有效的实用方法。选择2003—01/2006—03在广东省荣军医院整形科就诊的面部深皱纹明显且有完整随访资料的受术者52例,使用解剖刀进行皮下切割,松解开皱纹深处皮肤与表情肌的粘连,并造成皮下组织创伤性增生,达到除皱的目的。根据早期6例病例术后1~6个月普遍出现创伤区增生过度的现象,通过调整切割层次、减轻创伤反应,采用以患者为试验对象的自身对照试验方法,观察改进后46例受术者术前、术后6个月及18个月面部深皱纹的深浅变化,将疗效分为四个等级进行评估:52例全部进入结果分析。①早期6病例术后1~6个月全部出现创伤区增生过度的现象。②改进后的46例,术后6个月、18个月面部深皱纹不同程度变浅,显效29例,有效10例,部分有效7例,无效0例,总有效率为100%,无一例创伤区增生过度的现象发生。改进后的金属软组织解剖刀除皱术,既能去除面部深皱纹,又能避免创伤区增生过度的发生。  相似文献   
560.
异丙酚激活蛋白激酶C对心肌缺血再灌注损伤的保护作用   总被引:4,自引:0,他引:4  
目的:观察异丙酚对大鼠离体心肌缺血再灌注的影响及蛋白激酶C激活的作用。方法:实验于2004-04/2005-03在河北省医学科学院药研室完成。48只大鼠离体心脏随机分为6组,每组8只。分别为:正常对照组,持续灌注Lock液65min;缺血再灌注模型组,用含脂肪乳对照的灌流液灌注15min后,以钳夹主动脉灌注管造成全心常温缺血25min后,恢复再灌注30min,灌流液与预灌时相同;异丙酚15,30,60μmol/L组,缺血前和再灌期的灌流液中分别含相应浓度的异丙酚,余同缺血再灌注模型组;异丙酚60μmol/L 蛋白激酶抑制剂5μmol/L组,灌流液中含5μmol/L的chelerythrine的灌流液,其余同异丙酚60μmol/L组。实验评估:①Powerlab/8s仪记录各组平衡末、缺血前及再灌30min时心率、左室发展压、左室舒张末压、左室压力变化速率、冠状动脉流量等心功能指标。②测定冠状动脉流出液中乳酸脱氢酶、磷酸肌酸激酶活性。③透射电镜观察心肌细胞超微结构变化。④差速离心提取心肌线粒体,测定线粒体超氧化物岐化酶、谷胱甘肽过氧化物酶、ATP酶活性和丙二醛含量。结果:48只大鼠均进入结果分析。①平衡灌注末、缺血前各组间心功能指标差异无显著性(P>0.05),再灌注30min末,异丙酚30,60μmol/L组左室发展压、左室压力变化速率、冠状动脉流量明显高于缺血再灌注模型组(P<0.05),左室舒张末压明显低于缺血再灌注模型组(P<0.05)。异丙酚60μmol/L 蛋白激酶C抑制剂5μmol/L组左室发展压、左室压力变化速率、冠状动脉流量明显低于单纯异丙酚60μmol/L组(P<0.05),但仍高于与缺血再灌注模型组(P<0.05)。②心肌缺血再灌后,冠状动脉流出液中乳酸脱氢酶和肌酸激酶活性明显高于正常对照组(P<0.05)。异丙酚30,60μmol/L组、异丙酚60μmol/L 蛋白激酶C抑制剂5μmol/L组乳酸脱氢酶、肌酸激酶活性明显低于缺血再灌注模型组(P<0.05),异丙酚60μmol/L 蛋白激酶C抑制剂5μmol/L组乳酸脱氢酶和肌酸激酶活性与异丙酚60μmol/L组无明显差异。③与缺血再灌注模型组相比,异丙酚组心肌损伤明显减轻,尤其是60μmol/L组,心肌纤维排列均匀,线粒体膜结构完整,仅轻度水肿,嵴清晰,糖原可见。异丙酚60μmol/L 蛋白激酶C抑制剂5μmol/L组心肌超微结构显示损伤程度重于异丙酚60μmol/L组。④异丙酚30,60μmol/L、异丙酚60μmol/L 蛋白激酶C抑制剂5μmol/L组丙二醛含量低于缺血再灌注模型组(P<0.05),ATP酶、超氧化物歧化酶、谷胱甘肽过氧化物酶活性明显高于缺血再灌注模型组(P<0.05)。异丙酚60μmol/L组与异丙酚60μmol/L 蛋白激酶C抑制剂5μmol/L组相比,上述指标无明显差异。结论:异丙酚对离体大鼠心肌缺血再灌注损伤有保护作用,可能与其抗脂质过氧化和激活蛋白激酶C有关。  相似文献   
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