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21.
The purpose of this study was to define, in a phase I study in leukemia, the maximally tolerated dose (MTD), major toxicities, and possible antitumor activity of Topotecan, a new topoisomerase I (topo I) inhibitor. Topotecan was delivered by a 5-day continuous infusion every 3 to 4 weeks to patients with refractory or relapsed acute leukemia, at doses ranging from 3.5 mg/m2 to 18 mg/m2 per course. Twenty-seven patients were treated, including 17 patients with acute myelogenous or undifferentiated leukemia, 7 with acute lymphocytic leukemia, and 3 with chronic myelogenous leukemia in blastic phase. Severe mucositis was the dose-limiting toxicity occurring in two of five patients treated with Topotecan 11.8 mg/m2 per course; a third patient had prolonged myelosuppression. At the MTD of 10 mg/m2 per course, 1 of 12 patients had severe mucositis and 5 had mild-to- moderate mucositis. Nausea, vomiting, diarrhea, and prolonged myelosuppression were uncommon. Three patients (11%) achieved a complete response, two (7%) had a partial response, and one (4%) had a hematologic improvement. The overall complete plus partial response rate was 19%, and 24% in acute myelogenous or undifferentiated leukemia. A novel in vitro assay that quantifies Topotecan-stabilized topo I-DNA complexes in patient samples was used, which demonstrated heterogeneity in the ability of Topotecan to interact with topo I, the intracellular target of Topotecan. This phase I study defined the MTD of Topotecan to be 10 mg/m2 by continuous infusion over 5 days every 3 to 4 weeks in patients with refractory or relapsed acute leukemia. Severe mucositis was the dose-limiting toxicity. Future studies will define the precise activity of Topotecan in different leukemia subsets, its efficacy in combination with other antileukemic drugs, and correlations between Topotecan-induced topo I-DNA complex formation and individual patient response to Topotecan.  相似文献   
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We have compared multiple assays for the P-glycoprotein (Pgp/MDR1) phenotype in fresh and thawed adult acute leukemia to validate and quantitate measures for the expression and function of Pgp. The results are related to the Pgp-expressing KB8 and KB8-5 call lines. The most sensitive assay was the measurement of modulation of the rhodamine 123 (R123) fluorescence by 2 micromol/L PSC833, followed by the modulation of the probe calcein-AM. We also found a good intralaboratory and interlaboratory correlation between the values of the R123/PSC833 assay for fresh as well as thawed samples. In addition, the affects of PSC833 on 3H-daunorubicin (DNR) accumulation, DNR fluorescence, and 3H- vincristine accumulation were very similar. The correlation between the DNR/PSC833 and R123/PSC833 test was r = .86 (N = 51). The modulation of drug accumulation by 8 micromol/L verapamil was the some as the PSC833 effect for DNR (117%, N = 21), but was higher for vincristine in every single case (161% v 121%, N = 22; P< .001), indicating additional verapamil effects, not related to Pgp. The correlation of the staining of viable cells for Pgp with the monoclonal antibody MRK16 was r = .77 (N = 52) for the R123/PSC833 functional test and r = .84 (N = 50) for the DNR/PSC833 test. From these results it could be calculated that a maximal increase of the mean DNR accumulation of about 50% can be achieved by blocking Pgp pump activity with PSC833 in leukemic blast samples with the highest mean Pgp expression. Subpopulations of blast calls with higher Pgp activity are likely to be present. Their relevance has to be studied further. The methods outlined here allow the reliable, quantitative monitoring of the Pgp/MDR1 phenotype in leukemias in multicentered, clinical Pgp modulation studies.  相似文献   
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OBJECTIVES: Cure from seizures due to cavernomas might be surgically achieved dependent on both, the complete removal of the cavernoma as well as its surrounding hemosiderin rim. High field intraoperative MRI imaging (iopMRI) and neuronavigation might play a crucial role to achieve both goals. We retrospectively investigated the long-term results and impact of intraoperative 1.5T MRI (iopMRI) and neuronavigation on the completeness of surgical removal of a cavernous malformation (CM) and its perilesional hemosiderin rim as well as reduction of surgical morbidity.  相似文献   
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Background

Adequate vitamin D concentrations during pregnancy are necessary to neonatal calcium homeostasis, bone maturation and mineralization. The aim of study is to evaluate serum vitamin D concentrations in mothers and their newborns and effect of vitamin D deficiency on pregnancy outcomes.

Methods

552 pregnant women were recruited from Tehran University educating hospitals in the winter of 2002. Maternal and cord blood samples were taken at delivery. The serum was assayed for 25-hydroxyvitamin D3, calcium, phosphorus and parathyroid hormone.

Results

The prevalence of vitamin D deficiency in maternal and cord blood samples were 66.8% and 93.3%, respectively (<35 nmol/l). There was significant correlation between maternal and cord blood serum concentrations of vitamin D. In mothers with vitamin D deficiency, cord blood vitamin D concentrations was lower than those from normal mothers (P = .001). Also, a significant direct correlation was seen between maternal vitamin D intake and weight gain during pregnancy.

Conclusion

Consideration to adequate calcium and vitamin D intake during pregnancy is essential. Furthermore, we think it is necessary to reconsider the recommendation for vitamin D supplementation for women during pregnancy.  相似文献   
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目的:观察经介入途径移植自体骨髓单个核细胞在股骨头坏死治疗中的应用,并评价其疗效。方法:选择2004-07/2005-11在解放军四六三院细胞治疗中心住院的,具有完整随访资料的股骨头坏死确诊患者共54例91髋。纳入确诊股骨头坏死,有关节疼痛、功能障碍等症状患者,性别、年龄不限;排除有严重心力衰竭、严重肾功能异常等不能耐受手术者。符合纳入标准54例,男45例,女9例,12~68岁。按ARCO分期Ⅱ期42髋,Ⅲ期47髋,Ⅳ期2髋。实验对象对治疗的相关内容知情同意并签知情同意。干预措施:抽取患者髂后上嵴骨髓进行单个核细胞悬液的制备。在DSA监视下将采集的单个核细胞混悬液经股动脉行Seldinger法穿刺,穿刺成功后,置入4F动脉鞘,经动脉鞘置入Cobra导管,将导管超选择至闭孔动脉及旋股内外侧动脉,平均注入单个核细胞悬液。术后定期随访症状变化情况,1年后复查X射线或CT,随访疼痛、关节活动度等情况。实验评估:①疼痛指数:无疼痛症状为3分,Harris髋关节评分疼痛分级A级;时有隐痛2分,Harris髋关节评分疼痛B级;轻度疼痛为1分,Harris髋关节评分疼痛C级;中度疼痛为0分,Harris髋关节评分疼痛D级。②功能指数:髋关节屈、伸、展、收、旋转度评分达Harris髋关节活动范围评分4~5分为3分;3~4分为2分;2~3分为1分;小于2分为0分。③X射线平片指数:股骨头形态无变化,应力骨小梁清晰,坏死区明显缩小为3分;坏死区略缩小为2分;治疗前后无明显变化为1分;坏死区扩大为0分。④血管指数:治疗后旋股内、外侧动脉及其分支增粗、增多,延长1cm以上者3分;1~0.5cm者2分;小于0.5cm者1分,无变化者0分。结果:54例患者均完成疼痛症状、关节功能及影像学随访1年。①术后12个月复查疼痛消失9髋,缓解61髋,无缓解21髋,缓解率为76.9%。②关节功能缓解33髋,无缓解58髋,缓解率为36.3%。③1年后X射线平片或CT、MRI示股骨头区可见不同程度的股骨头坏死区骨质密度改变,坏死区有吸收、缩小,股骨头形态变圆滑规整,改善28髋,无缓解或加重63髋,缓解率为30.1%。④12例24髋完成术后12个月复查股骨头供血动脉数字减影血管造影,好转18髋,好转率为72.2%。结论:经介入途径移植自体骨髓单个核细胞治疗股骨头坏死损伤小,可缓解临床相关症状。  相似文献   
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Background  

Physical activity has been associated with a decreased risk for breast cancer. The biological mechanismn(s) underlying the association between physical activity and breast cancer is not clear. Most prominent hypothesis is that physical activity may protect against breast cancer through reduced lifetime exposure to endogenous hormones either direct, or indirect by preventing overweight and abdominal adiposity. In order to get more insight in the causal pathway between physical activity and breast cancer risk, we designed the Sex Hormones and Physical Exercise (SHAPE) study. Purpose of SHAPE study is to examine the effects of a 1-year moderate-to-vigorous intensity exercise programme on endogenous hormone levels associated with breast cancer among sedentary postmenopausal women and whether the amount of total body fat or abdominal fat mediates the effects.  相似文献   
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反应停治疗难治性多发性骨髓瘤25例   总被引:3,自引:0,他引:3  
1临床资料我院2001-02/2004-01接受2个疗程卡氮芥 环磷酰胺 马法兰 泼尼松 长春新碱或2个疗程长春新碱 阿霉素 地塞米松方案化疗无效或复发的难治性多发性骨髓瘤患者25(男16,女9)例,年龄42~80(中位年龄57.2)岁.单用反应停口服治疗,起始剂量200 mg/d,如无不良反应,每周增加100 mg,根据患者耐受情况,最高剂量为600 mg/d,3 mo为1疗程.服药期间禁止使用糖皮质激素类药物及细胞毒药物.  相似文献   
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