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1.
按WHO抗癌药急性及亚急性毒性分级标准 ,对 650例化、放疗肿瘤患者分别作了治疗前后毒性反应的总分值统计。结果加服PSP组 ( 557例 )的疗后总分值为837,低于疗前的 962 ;而 93例阳性对照组 (加服鲨肝醇 )疗前总分为 157,疗后为 2 4 1,疗后总分高于疗前。用Wilcoxon两样本秩和统计法检验 ,PSP组和对照组间具有极显著差异 ,表明PSP对比、放疗药物引起的毒副反应有明显降低效应。  相似文献   
2.
以苯胺为原料,经异丙基化、与2-氯-1-(4-氟苯基)乙酮缩合、催化分子内环合制得合成氟伐他汀的关键中间体——3-(4-氟苯基)-1-(1-异丙基)-1H-吲哚,总收率高于90%,其结构经1HNMR确证。  相似文献   
3.
区域水资源承载力模糊线性规划模型及应用   总被引:1,自引:0,他引:1  
首先按照联合国教科文组织提出的资源承载力定义,给出水资源承载力的定义,建立了水资源承载力的模糊线性规划模型,然后运用这模型对江西省的近期水资源承载力问题进行研究,数据结果表明模型的应用是成功的.  相似文献   
4.
Two eukaryotic vectors expressing 9 tandem repeats of human MUCI(VNTR), VR1012-VNTR, and pEGFP-VNTR, were constructed by cloning VNTR gene into VR1012 and pEGFP, respectively. VNTR stably expressing murine Lewis lung carcinoma(LLC) cell line(VNTR^+ LLC) was established by Lipofectamine-mediated transfection of pEGFP-VNTR into LLC cells. The EGFP expression was observed under a fluorescent microscope and VNTR expression in VNTR^+ LLC cells was confirmed by means of Western blotting. A syngenic graft tumor model was generated by subcutaneous injection of VNTR^+ LLC cells into C57/BL6 mice and tumor size increased rapidly with time and in a cell qumber dependent manner. VNTR mRNA expression in the tumor formed was confirmed by RT-PCR. After the third immunization mice were challenged subcutaneously with 5×10^5 VNTR^+ LLC cells, a significant reduction of subcutaneous tumor growth was observed in the groups immunized with VNTR plasmid DNA compared with that in the groups immunized with the vector DNA alone. Thus, the suppression of subcutaneous tumor was antigen-specific. This model is useful for the development of tumor vaccines targeting MUCI VNTRs.  相似文献   
5.
Survivin, a novel member of inhibitor of apoptosis(IAP) protein family, is aberrantly expressed in cancer but undetectable in normal, differentiated adult tissues. The cancer-specific expression of survivin, coupled with its importance in inhibiting cell death and in regulating cell division makes it a useful diagnostic marker of cancer and a potential target for cancer treatment. Survivin cDNA amplified from the total RNA of 293 cells through RT-PCR was cloned into prokaryotic expression vector pRSET-B. The recombinant plasmid pRSET-B-Surv was expressed in E.coli BL21, and the relative molecule mass(Mr) of expressed fusion protein was approximately 21000. The recombinant protein was purified through Ni^2+ affinity chromatography column and characterized by SDS-PAGE and Western blot. The purified recombinant protein was then injected into rabbits, and antisurvivin polyclonal antibody with a high titer was obtained.  相似文献   
6.
In present paper, we obtain the inverse moment estimations of parameters of the Birnbaum-Saunders fatigue life distribution based on Type-Ⅱ bilateral censored samples and multiply Type-Ⅱ censored sample. In this paper, we also get the interval estimations of the scale parameters.  相似文献   
7.
In present paper, we derive the quasi-least squares estimation(QLSE) and approximate maximum likelihood estimation(AMLE) for the Birnbaum-Saunders fatigue life distribution under multiply Type-Ⅱcensoring. Furthermore, we get the variance and covariance of the approximate maximum likelihood estimation.  相似文献   
8.
In this paper, the Schwarz Information Criterion (SIC) is used to detect the change points in polynomial regression models. Switching quadratic regression models with same amount of model deviation and switching polynomial regression models with different amount of model deviation for different segments of regression are considered. The number of separate regimes and their corresponding regression orders are assume to be known. The method is then applied to cable data sets and the change points are successfully detected.  相似文献   
9.
TFR模型序加试验下WEIBULL分布产品寿命的统计分析   总被引:7,自引:2,他引:7  
本文针对损伤效率(TFR)模型,首次提出将步加试验推广至序加试验,给出了两参数Weibull分布参数的极大似然估计.  相似文献   
10.
给出了多组序进应力加速寿命试验下指数分布的极大似然估计的存在和唯一的一个充要条件;模拟比较了一组与二组序进应力加速寿命试验下有关参数估计的差异:对Weibull分布给出了有关参数的联合置信域.  相似文献   
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