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91.
目的:探讨程序公平对工作满意度、组织承诺的影响以及工作不安全感在其中的中介作用。方法:对来自国内某大型国营企业592名员工的关于程序公平、工作满意度、组织承诺和工作不安全感的问卷调查数据进行中介回归分析(Mediatingregressionanalysis)。结果:①程序公平和员工的工作满意度、组织承诺存在显著的正向关系,而和其工作不安全感之间存在显著的负向关系;②工作不安全感部分中介程序公平对整体工作满意度和组织承诺的影响。结论:通过改善程序公平,可以减少员工的工作不安全感,并进而增强其工作满意度和组织承诺。  相似文献   
92.
目的 评价思维活动对脑动脉血流速度的影响。方法 经颅多普勒检测 10例正常人大脑思维活动前、后大脑中动脉、大脑前动脉和大脑后动脉的血流速度。结果 大脑思维活动后各动脉血流速度对称性增加 ,增加范围 10 3%~ 14 3% ,其中以颈内动脉系统血流速度增加明显。结论 思维活动能明显增加脑动脉血流速度。  相似文献   
93.
目的:观察8-Br-cAMP对人肺癌NSCLC-3细胞凋亡相关基因表达的影响.方法:将体外培育的NSCLC-3细胞分为实验组和对照组,采用原位杂交方法观察8-Br-cAMP对NSCLC-3细胞c-myc、bcl-2基因表达的影响.结果:8-Br-cAMP处理后的实验组较未加8-Br-cAMP的对照组c-myc、bcl-2基因表达降低(P<0.01).结论:8-Br-cAMP可下调与NSCLC-3细胞凋亡相关的c-myc、bcl-2基因表达.  相似文献   
94.
用原子吸收光谱法测定良性前列腺增生 (BPH)和前列腺癌 (PCa)患者及健康者头发中铜、锌、铁、锰和镉5种元素的含量。结果表明 :PCa患者发锌含量较健康者及BPH显著减少 (P <0 .0 1) ,而其他 4种微量元素在三组间差异无显著性 (P >0 .0 5 )。发锌含量的显著降低 ,可能为早期前列腺癌的诊断提供重要线索  相似文献   
95.
下颈椎后路固定方法的力学比较   总被引:5,自引:0,他引:5  
目的:评价不同于颈椎后路内固定器的生物力学性能。方法:应用5具新鲜尸体颈椎标本(C2 ̄C7)建立脱位模型后,依次用棘突钢丝、侧块螺钉、自制螺钉、椎弓根螺钉固定,用材料试验机测算其垂直压缩刚度,前后水平剪切刚度和左右水平剪切刚度。结果:棘突钢丝的垂直压缩刚度和前后剪切刚度虽较完整颈椎增大,但无显著性差异(P〉0.05),而左右剪切刚度尚较完整颈椎减小(P〈0.05)。侧块螺钉、自制螺钉和椎弓根螺钉的  相似文献   
96.
Nutrient-induced thermogenesis (NIT) induced by parenteral infusion of amino acid (AA) mixtures of different composition and of the same AA mixtures given via different routes (parenteral or intraportal infusion) were investigated in rats using a small animal indirect calorimeter. When 8 different AA solutions of differing composition but with the same total concentration were infused parenterally, both standard NIT (each AA is assumed to generate 3.28 kcal/g) and specific NIT (heat energy of each AA is calculated assuming that it is oxidized to carbon dioxide and water, and metabolised to urea and sulphuric acid) values of the leucine (Leu)-rich and the glycine (Gly)-rich solutions were significantly greater than those of the control solution. Removal of Leu or Gly from the respective AA solutions reversed the increase of both NIT values down to control levels. When the parenteral and portal infusion routes were used in one rat, both NIT values for parenteral infusion of the Leu-rich solution were again significantly greater than those of the control. Likewise, both NIT values for intrportal infusion of the Leu-rich solution were also significantly greater than those of the control. However, no difference in NIT values was found between parenteral and portal infusion of either solution. The result of this study indicated that Leu and Gly may be thermogenic AAs, and the thermogenic effect of Leu is not dependent upon the route of infusion.  相似文献   
97.
中药有效成分研究与复方新药开发   总被引:2,自引:0,他引:2  
100000首方剂是开发中药复方新药的宝库。12772种中药及其复方中的有效成分是开发中药复方新药的基础。逆向思维、利用文献、研究有效成分动态变化和综合作用是开发中药复方新药的几种途径  相似文献   
98.
99.
Replacement of the mitral valve in the presence of extensive calcification of the posterior annulus is a technical challenge. The heavily calcified annulus often results in difficulties of seating the prosthesis and later periprosthetic leakage. A radical calcium debridement may leave a friable and thin annulus that contributes to the risks of prosthesis dehiscence and ventricular perforation. To avoid technical difficulties and associated catastrophic complications, we devised a new technique of mitral valve replacement that allows a surgeon to implant a prosthesis securely. This technique involves inserting a larger single tilting disc mechanical valve (Medtronic Hall disc) with intra-atrial anchorage over the posterior sector of the calcified annulus, orienting the working (major) orifice of the mechanical valve anteriorly, and thereby tilting the lesser occluder segment of the disc upward into the atrium and away from the calcification in diastole. By utilizing this method, we have successfully performed mitral valve replacement in two patients who exhibited massive calcification of the posterior mitral annulus. Postoperative transeosophageal echocardiography showed excellent hemodynamic performance of the implanted valves. We therefore recommend this simple, safe, and time-saving procedure as a feasible method to deal with this surgical dilemma.  相似文献   
100.
To evaluate the effect of interferon-γ-genetransduced cells, DS mice were inoculated into their footpads with syngeneic mammary adenocarcinoma SC42 admixed with interferon-γ producing mammary adenocarcinoma SC115Kγ, which had been established by an interferon-γ-gene transduction in another syngeneic mammary adenocarcinoma SC115 using retroviral vectors. These mice rejected both tumor cells and developed resistance to subsequent challenges with either SC115 or SC42 cells inoculated into their opposite posterior footpads. These results thus indicate that systemic immunological memory to each of the independent tumor cell lines developed in these mice. Although the SC42 cells admixed with irradiated SC115Kγ cells were rejected by these mice, the SC42 cells admixed with irradiated SC115neoR, in which the neo-gene had been transduced, were observed to proliferate. Tumor rejection was reversed by an in vivo administration of anti-interferon-γ antibody, thus suggesting that locally produced interferon-γ plays an important role in tumor elimination and immunological memory induction. In conclusion, interferon-γ-gene-transduced tumor cells are therefore considered to have a therapeutic potential for other types of malignant tumor cell lines.  相似文献   
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