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用离体大鼠肝脏灌流法,研究了抗痫灵在肝脏灌流过程中的代谢规律。用高效液相色谱法由灌流液中分离、制备得到了两种代谢物,经紫外吸收光谱与质谱鉴定,确定代谢物的结构为3,4-次甲基二氧桂皮酰羟基哌啶及阿魏酰哌啶,后者经化学合成得到了进一步的确证。本文还研究了肝循环过程中抗痫灵的代谢动力学,揭示了大部份抗痫灵以原形结合贮存于肝脏中。  相似文献   
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目的:分析非亲缘异基因外周血干细胞移植治疗幼儿急性非淋巴性白血病的可行性。方法:患儿,男,3岁,于2005-07-18为行造血干细胞移植入本院血液科骨髓移植病房,入院诊断为急性非淋巴细胞性白血病-M5b。经抗肿瘤药物治疗病情获得完全缓解。患儿首先接受清髓性预处理,然后接受同性别非亲缘异基因外周血造血干细胞移植。①移植预处理包括马利兰、阿糖胞苷和环磷酰胺。移植前依次用药为马利兰3.2mg/(kg·d)×4d,口服,于移植前6,7,8,9d给药;阿糖胞苷3.2g/(m2·d)×2d,于移植前4,5d给药;环磷酰胺54mg/(kg·d),于移植前2,3d给药。②急性移植物抗宿主病的预防用药包括环孢菌素A和氨甲蝶呤、抗胸腺细胞球蛋白及吗替麦考酚酯。供者接受粒细胞集落刺激因子动员4d后采集外周血造血干细胞,供、受者间HLA全相合,患者血型A,供者血型B,主次要均不合。结果:①患儿移植后早期获得造血重建,中性粒细胞>0.5×109L-1和血小板>50×109L-1的天数分别是12d和11d。②移植后1个月经DNA短串联重复序列多态性分析证明为供者型完全植入,移植后3个月查骨髓象正常。③移植后3,6个月定期行淋巴细胞亚群检查表明除CD19 ,CD4 细胞未恢复外,自然杀伤细胞在移植后3个月恢复正常,T淋巴细胞CD3 与CD8 、体液免疫球蛋白在移植后6个月中均获得重建。④整个移植过程顺利,未出现明显感染和重度急性移植物抗宿主病。移植后96d时出现Ⅰ度皮肤移植物抗宿主病,经加用激素治疗,皮疹消失。移植术后已随访观察12个月,患儿正常生活。结论:如果患儿有HLA完全相合的供者,非亲缘异基因外周血干细胞移植治疗儿童高危白血病是一种有效和安全的方法,对国内独生子女家庭拓宽供者来源有重要的实用价值。  相似文献   
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Multidrug-resistant (MDR) myeloma patients failing chemotherapy may express P-glycoprotein (PGP), which serves as an efflux pump protecting the neoplastic cells. Unknown is whether PGP expression might relate to prior cytotoxic drug exposure. To address this question, we studied 106 consecutive bone marrow samples from 104 myeloma patients with samples studied either before or after therapy and at the time of relapse. We performed an established immunocytochemical assay of PGP using an MDR-1- specific monoclonal antibody and correlated PGP status with prior chemotherapy dosage. Myeloma patients with no prior therapy had a low incidence of PGP expression (6%, 3/47), whereas those receiving chemotherapy had a significantly higher incidence (43%, 21/49) (P < .0001). A substantially higher incidence of PGP expression (50%, 83%, respectively) occurred when the total vincristine dose exceeded 20 mg and when doxorubicin exceeded 340 mg. In the 11 patients who received both high vincristine and doxorubicin dosages (> 20 mg, > 340 mg total dose) there was 100% incidence of PGP expression in the tumor cells. These data provided the basis for a predictive mathematical model from which dose-related PGP expression normograms were generated. Time with myeloma for PGP-negative patients (mean 33 months) had overlapping confidence limits with PGP-positive patients (mean 42 months), suggesting that disease duration was not a significant variable. PGP expression did not correlate with other clinical factors or immunophenotypic factors. Our findings indicate a strong correlation between PGP expression in myeloma and past chemotherapy in myeloma, in particular, related to prior exposure to the natural product agents vincristine and doxorubicin. Additionally, the proportion of PGP- positive plasma cells was significantly higher in the doxorubicin- treated patients than the nondoxorubicin-treated patients (87.7% v 65.17%; P = .013). Combined high vincristine and doxorubicin total dosage appear highly predictive of PGP expression.  相似文献   
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A critical determinant of the efficacy of antineoplastic therapy is the response of malignant cells to DNA damage induced by anticancer agents. The p53 tumor-suppressor gene is a critical component of two distinct cellular responses to DNA damage, the induction of a reversible arrest at the G1/S cell cycle checkpoint, and the activation of apoptosis, a genetic program of autonomous cell death. Expression of the BCR-ABL chimeric gene produced by a balanced translocation in chronic myeloid leukemia, confers resistance to multiple genotoxic anticancer agents. BCR-ABL expression inhibits the apoptotic response to DNA damage without altering either the p53-dependent WAF1/CIP1-mediated G1 arrest or DNA repair. BCR-ABL-mediated inhibition of DNA damage-induced apoptosis is associated with a prolongation of cell cycle arrest at the G2/M restriction point; the delay of G2/M transition may allow time to repair and complete DNA replication and chromosomal segregation, thereby preventing a mitotic catastrophe. The inherent resistance of human cancers to genotoxic agents may result not only by the loss or inactivation of the wild-type p53 gene, but also by genetic alterations such as BCR-ABL that can delay G2/M transition after DNA damage.  相似文献   
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Ilizarov frames provide a versatile fixation system for the management of bony deformities, fractures and their complications. The frames give stability, soft tissue preservation, adjustability and functionality allowing bone to realise its full osteogenic potential. It is important that we have a clear and concise understanding of the Ilizarov principles of deformity correction to best make use of this fixation system. In this review article, the history of Ilizarov frame, the basic sciences behind it, the mechanical principles governing its use and the clinical use of the fixation system are discussed.  相似文献   
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Background  

Pregnancy-related pelvic girdle and/or low back pain is a controversial syndrome because insight in etiology and prognosis is lacking. The controversy relates to factors eliciting pain and some prognostic factors such as the interpretation of pain at the symphysis. Recent research about treatment strategies also reflects those various opinions, in fact suggesting there is professional uncertainty about the optimal approach. Currently, physiotherapists often prescribe a pain-contingent treatment regime of relative rest and avoiding several day-to-day activities. Additionally, treatment more often includes an exercise program to guide rectification of the muscle imbalance and alignment of the pelvic girdle. Effectiveness of those interventions is not proven and the majority of the studies are methodologically flawed. Investigators draw particular attention to biomedical factors but there is growing evidence that important prognostic issues such as biopsychosocial factors appear to be even more important as point of action in a treatment program.  相似文献   
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