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111.
脾虚证大鼠侧脑室注射孤啡肽对细胞免疫功能的影响 总被引:1,自引:0,他引:1
目的脾虚证大鼠侧脑室注射孤啡肽,研究其对细胞免疫功能的影响,从神经内分泌的角度探索脾虚的细胞免疫学变化本质。方法用100%大黄煎剂灌胃复制脾虚证大鼠模型,四君子汤作为反证药物,侧脑室埋管,注射孤啡肽,MTT法检测脾T淋巴细胞增殖能力、足跖增厚法检测迟发型变态反应程度,判定细胞免疫功能改变情况。结果灌服大黄煎剂后,大鼠逐渐出现腹泻,或伴有脱肛,食量减少,精神不振,懒动,被毛失去光泽,形体消瘦等脾虚症状,而空白对照组(BC组)没有上述症状;T淋巴细胞增殖能力、迟发型变态反应程度与BC组比较明显减弱(P<0.01)。四君子汤治疗组(DFMD组)和孤啡肽组(OFQ组)大鼠上述脾虚症状及检测指标明显改善(P<0.01)。结论脾虚证大鼠侧脑室注射孤啡肽能提高细胞免疫功能。 相似文献
112.
生物接触氧化法处理洗浴废水的填料选择研究以软性纤维和软性泡沫作为备选填料,采用活性污泥挂膜法,浅析了膜培养过程中的影响因素.最后通过最佳水力停留时间这一废水处理指标对备选填料进行比较,最终选择软性泡沫作为动态实验填料. 相似文献
113.
城市出租汽车服务站普遍存在建设无序与低效的情况,需进行合理布局规划。以广西壮族自治区柳州市为例,对出租汽车驾驶员进行问卷调查。分析出租汽车驾驶员特征、驾驶员对服务站功能的选择意向,并采用分形理论分析服务站选址分布与城市空间形态的关系。结果显示:出租汽车服务站的服务功能应以解决驾驶员停车、休息、就餐、如厕等基本需求为主;驾驶员年龄因素对服务功能选择有较为明显的影响;服务站的规划建设应密切依托城市空间形态及城市道路网、人口、用地等城市构成要素分布。通过将出租汽车微观数据与城市宏观形态相结合,为城市出租汽车服务站规划与评价提供新的视角。 相似文献
114.
Traditional quality inspection based product quality evaluation method with complex process has high operating cost and requires more professional knowledge. To remove the above limitation, this paper leads product gene theory into product quality evaluation. Methods of quality influencing factors based modeling and encoding are established. Combined with similarity theory and product gene theory, a product gene similarity analysis based quality evaluation method is proposed. The proposed method is low cost, operates easily and requires less specialized knowledge. A case study is conducted to prove the correctness and feasibility of this method. 相似文献
115.
Weight reduction has attracted much attention among ship designers and ship owners. In the present work, based on an improved bi-directional evolutionary structural optimization (BESO) method and surrogate model method, we propose a hybrid optimization method for the structural design optimization of beam-plate structures, which covers three optimization levels: dimension optimization, topology optimization and section optimization. The objective of the proposed optimization method is to minimize the weight of design object under a group of constraints. The kernel optimization procedure (KOP) uses BESO to obtain the optimal topology from a ground structure. To deal with beam-plate structures, the traditional BESO method is improved by using cubic box as the unit cell instead of solid unit to construct periodic lattice structure. In the first optimization level, a series of ground structures are generated based on different dimensional parameter combinations, the KOP is performed to all the ground structures, the response surface model of optimal objective values and dimension parameters is created, and then the optimal dimension parameters can be obtained. In the second optimization level, the optimal topology is obtained by using the KOP according to the optimal dimension parameters. In the third optimization level, response surface method (RSM) is used to determine the section parameters. The proposed method is applied to a hatch cover structure design. The locations and shapes of all the structural members are determined from an oversized ground structure. The results show that the proposed method leads to a greater weight saving, compared with the original design and genetic algorithm (GA) based optimization results. 相似文献
116.
A series of Pd/Co3O4 catalysts were prepared by Self-Propagating High-Temperature Synthesis (SHS) method in this study, and electric field was applied for catalytic combustion of lean methane over Pd/Co3O4 catalysts at low temperature. When electric field was applied, the catalytic combustion performance of Pd/Co3O4 catalysts was greatly improved, and the application of electric field could reduce the load of active element Pd to some extent while maintaining the same efficiency. Based on experimental tests and the analysis results of X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), H2-temperature-programmed reduction (H2-TPR) and in-situ diffuse reflectance infrared Fourier transform spectroscopy (in-situ DRIFTS), the mechanism of catalytic oxidation of CH4 over Pd/Co3O4 catalysts in electric field was proposed. The catalytic combustion of CH4 occurs only when the temperature is higher than 250 °C normally, but when electric field was applied, the whole process of CH4 oxidation was promoted significantly and the reaction temperature was reduced. Electric field could promote the reduction of the support Co3O4 to release the lattice oxygen, resulting in the increase of PdOx and the surface chemisorbed oxygen, which could provide more active sites for the low-temperature oxidation of CH4. Furthermore, electric field could accelerate the dehydroxylation of CoOOH to further enhance the activity of the catalysts. 相似文献
117.
Polarization pattern provides additional information besides spectral signatures. It can be used in many applications, such as navigation, defect detection and object identification. A novel polarization camera composed of four synchronized cameras is proposed, and it can realize real-time polarization measurement. This study particularly concentrates on the geometric calibration of the system. The projection model is analyzed and the multi-camera calibration algorithm is proposed. Firstly, each camera is calibrated separately using planar patterns, and then the geometric calibration algorithms are performed. Due to the geometrical constraint, a global optimization method results in smaller estimation uncertainties. A mean rotation error of 0.025° and a mean translation error of 0.26mm are achieved after geometric calibration. The images are rectified to establish a correspondence among cameras and are combined to acquire the polarization measurement. The polarization pattern of the skylight is measured by the system and the results are consistent with the previous studies. 相似文献
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Cheng Xiaoling He Ling 《河北交通科技》2007,(4)
针对目前农村客运站建设与管理中存在的客运站点建设跟不上发展、客运市场经营主体混乱等问题,提出合理安排农村客运站点布局的原则以及"站所合一"、"三定四统一"等管理模式,以扭转农村客运市场的混乱局面。 相似文献