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【目的】对典范性状对进行决策分析,为多数量性状的选择提供一种简便的方法。【方法】运用通径分析的决策分析方法对典范组合性状对进行决策分析。【结果】建立了典范性状对的通径分析模型;分析得到典范性状对可以用以供选择的各性状xi(i=1,2,…,m)为因,典范目标性状Hig为果的中心线性回归模型表述;定义了各选择性状对典范目标性状的决策系数,各决策系数代表了各选择性状对典范目标性状的综合效用。【结论】通过各性状决策系数的确定,选择组合性状中的主载性状、限制性状和辅助性状,育种者就可根据个体的性状表现来选择,以达到对典范目标性状所期望的遗传进展。 相似文献
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以终浓度为10μmol/L CdCl2对体外培养淋巴细胞进行染毒,分别培养12、24、36、48和72h时收集细胞,提取体外培养脾淋巴细胞膜,采用试剂盒比色的方法,分别检测了细胞膜GSH-Px、SOD的活性、膜MDA和SA含量及培养液LDH的活性,来观察镉性细胞损害时细胞膜的抗氧化功能和通透性。结果显示,随着镉作用时间的延长,淋巴细胞膜GSH-Px、SOD的活性降低,MDA生成量增加,试验组与对照组差异显著(P〈0.05)或极显著(P〈0.01);培养液中LDH活性升高,膜SA含量降低。表明镉可使淋巴细胞膜的抗氧化功能降低,膜完整性被破坏。 相似文献
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AIM: To observe the effect of Armadillo repeat-containing X-linked protein 1 (ARMCX1) on the proliferation and apoptosis of human cervical cancer SiHa cells by knock-down of ARMCX1 expression with small interfering RNA. METHODS: After knock-down of ARMCX1 expression, the cell cycle distribution and apoptosis of SiHa cells were detected by flow cytometry. The proliferation of SiHa cells was observed by plate colony formation assay after knock-down of ARMCX1 for 10 d. The protein levels of cell proliferation-and apoptosis-related molecules were determined by Western blot. RESULTS: After knock-down of ARMCX1 expression in the SiHa cells, the cell colony formation ability was significantly inhibited (P < 0.05), the cell cycle was arrested in S phase, and the protein levels of cyclin E and cell division cycle 25A (Cdc25A) in the SiHa cells were decreased. Meanwhile, knock-down of ARMCX1 expression promoted the apoptosis of SiHa cells, significantly reduced the protein expression of Bcl-2, and significantly increased the protein levels of Bax and active caspase-3 (P < 0.05). CONCLUSION: Knock-down of ARMCX1 expression inhibits the proliferation of SiHa cells and induces apoptosis. 相似文献
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为研究Hiper Strut(High Performance Strut)新型悬架对整车操纵稳定性的影响,将一款国产SUV所使用的麦弗逊前悬架替换为适用于该车的Hiper Strut前悬架.利用Adams/Car建立使用Hiper Strut前悬架的整车仿真模型,并进行相关操纵稳定性仿真试验.仿真结果表明,使用该新型悬架的整车在操纵稳定性评价中得分较高,说明Hiper Strut悬架的结构设计有助于提高整车操纵稳定性.所建模型及仿真分析对Hiper Strut新型悬架的深入研究和推广应用具有一定的实际参考价值. 相似文献
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AIM: To study the function of proliferation and differentiation of bone marrow mesenchymal stem cells (BMSCs) for bone loss in the pathogenesis of osteoporosis (OP) in ovariectomized rats. METHODS: Animal model of OP was established by ovariectomy (OVX,bilateral ovarian resection) in 10-week-old healthy female Sprague-Dawley (SD) rats.BMSCs were isolated, cultured and purified by the combination of density gradient centrifugation, adhesion separation and limited dilution method, and cultured in vitro to the 3rd~4th passage in all experiments. The BMSCs phenotype appraisal was studied by flow cytometry. Colony-forming assay was applied to detect the BMSCs proliferation ability. The MTT method was used to analyze the growth curves of BMSCs. After adipogenic induction (ADI), lipid drops were observed by oil red O staining to compare the adipogenic potential between the 2 kinds of BMSCs. After osteogenic induction (OSI), calcium nodules were observed by alizarin red staining (ARS). The mRNA expression levels of BMSCs osteogenesis-related proteins, for instance, Runx2, osteocalcin (OCN) and osteopontin (OPN) were measured by RT-PCR. RESULTS: Compared with sham group, the colony-forming ability of BMSCs in OVX group became decreased, the proliferation capacity was declined, the osteogenic potential was decreased, and the adipogenic potential was increased(P<0.05). CONCLUSION: In ovariectomized OP rats, the proliferation and osteogenesis of BMSCs decrease, and the adipogenesis of BMSCs increases, which may cause rapid bone loss and play an important role in the pathogenesis of OP. 相似文献
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南瓜皮类胡萝卜素的提取工艺研究 总被引:1,自引:0,他引:1
南瓜皮中富含功能性色素——类胡萝卜素,类胡萝卜素有抗氧化、防癌症、预防夜盲症、着色力强等功能。为了提供类胡萝卜素的应用和稳定性研究基础,以南瓜皮为原料,对其中的类胡萝卜素进行提取研究,以丙酮和石油醚为溶剂,采用超声波辅助溶剂提取,以提取温度、提取时间、提取料液比为三因素进行三因素三水平正交实验,研究南瓜皮类胡萝卜素最佳提取工艺。结果表明,当超声波功率为150W时,利用丙酮+石油醚为提取溶剂,在提取温度为30℃,提取时间为30min,提取料液比为1:10时,南瓜皮类胡萝卜素提取率最高。由此得出,利用混合溶剂辅助超声波提取南瓜皮类胡萝卜素,提取周期短,提取率高,提取出的高纯度类胡萝卜素可以为后期的稳定性研究提供理论基础。 相似文献
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刘振义 《农业图书情报学刊》2012,(3):34-37,40
通过用"ABC"分类法对辽宁工业大学2000~2009年间图书借阅使用情况进行分析,查找出图书采购的主要问题,并对如何加强和提高采购工作质量提出了具体的解决办法,对今后一个时期内的图书采购工作提出指导性意见。 相似文献