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61.
目的:应用微乳液反应法制备磺胺嘧啶银均匀微晶,均匀制得的微晶的粒径大小约为2~4um,均匀微晶的结晶性好,纯度高。用均匀设计方法优化条件,制备的均匀的微晶平均粒径大小为2.09um,实验结果达到预测结果要求。结论:用微乳液反应法能获得磺胺嘧啶银均匀微晶。  相似文献   
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Inflammation-mediated carcinogenesis develops in the context of chronic inflammation and is a significant cause of cancer within the digestive system. In the chronic inflammation microenvironment, the metabolic activity of tissue cells undergoes extensive changes, which interfere with the normal function of immune cells. Dysregulation of cell metabolism and immune function has been identified as a key factor contributing to inflammation-mediated carcinogenesis within the major digestive organs, such as the stomach, liver, and colorectum. This metabolic–immune imbalance also corresponds to traditional Chinese medicine (TCM) theories of “yin-yang disharmony” and “disharmony between Ying-nutrients and Wei-defense.” The metabolic–immune imbalance has also been regarded as the key factor supporting “treatment of different diseases with the same method,” in which the same approach is adopted in the treatment of different conditions. In the TCM treatment process, it is necessary to first identify TCM patterns and then apply the corresponding TCM to correct the dysregulated metabolic and immune function, thereby blocking the progression from inflammation to malignancy. Our study findings deepen the TCM understanding of metabolic–immune dysregulation and the relationship between metabolic–immune dysregulation, pattern identification, and treatment method. They also provide new insights for the treatment of inflammation-mediated carcinogenesis in major digestive organs and help us further explore the scientific connotation of the TCM strategy of “treating different diseases with the same method.  相似文献   
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In this work, a novel and simple phase-field-based lattice Boltzmann (LB) method is proposed for the axisymmetric two-phase electro-hydrodynamic flows. The present LB method is composed of three LB models, which are used to solve the axisymmetric Allen-Cahn equation for the phase field, the axisymmetric Poisson equation for the electric potential, and the axisymmetric Navier-Stokes equations for the flow field. Compared with the previous LB models for the axisymmetric Poisson equation, which can be viewed as the solvers to the convection-diffusion equation, the present model is a genuine solver to the axisymmetric Poisson equation. To test the capacity of the LB method, the deformation of a single leaky or perfect dielectric drop under a uniform electric field is considered, and the effects of electric strength, conductivity ratio, and permittivity ratio are investigated in detail. It is found that the present numerical results are in good agreement with some available theoretical, numerical and/or experimental data.  相似文献   
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Summary The contours of pressure and flow of a pulse wave arriving at the entrance of a collapsed segment of an elastic tube can be described by application of the basic laws of reflection. The collapsed segment acts like a valve. It is opened by the pressure of the pulse wave when the pressure within the tube becomes higher than the collapse pressure, i.e. the pressure exerted on the segment from outside. This opening of the collapsed segment suddenly changes the sign of the pulse wave reflection from positive to negative; thus a typical contour change of the pulse proximal to the segment is observed. The most obvious effect is a reduction of the pulse pressure. The extent of this reduction is a function of the collapse pressure.A typical example of this phenomenon can be observed in an artery proximal to the segment which is collapsed due to the pressure exerted by an inflated Riva-Rocci cuff. The effect is explained by the assumption that the sign of reflection changes when the pressure of the pulse wave crosses the level of the cuff pressure. This explanation is supported by the results of model experiments.  相似文献   
69.
As the auscultatory method of blood pressure measurement relies fundamentally on the generation of the Korotkoff sound, identification of the responsible mechanisms has been of interest ever since the introduction of the method, around the turn of the century. In this article, a theory is proposed that identifies the cause of sound generation with the nonlinear properties of the pressure-flow relationship in, and of the volume compliance of the collapsible segment of brachial artery under the cuff. The rising portion of a normal incoming brachial pressure pulse is distorted due to these characteristics, and energy contained in the normal pulse is shifted to the audible range. The pressure transient produced is transmitted to the skin surface and stethoscope through deflection of the arterial wall. A mathematical model is formulated to represent the structures involved and to computer the Korotkoff sound. The model is able to predict quantitatively a range of features of the Korotkoff sound reported in the literature. Several earlier theories are summarized and evaluated.  相似文献   
70.
积分加权法评价磷化学烧伤实验病理的意义与应用   总被引:6,自引:0,他引:6  
目的:积分加权法在病理组织学检查中的应用,方法:在常规病理描述基础上,采用积分加权法将病理结果予以定量,综合评价致伤后实验动物的主要脏器,结果:实验动物同等面积的磷酸烧伤各脏器积分降低,钙治疗后则显著改善,均与其它方面报道的资料一致,结论:积分加以数值使各脏器损伤程度一目了然,对不同脏器间的损伤情况有可比性,从而有助于了解主要受损脏器与总体的关系以及药物的治疗效果。  相似文献   
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