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21.
正清风痛宁缓释片治疗类风湿关节炎60例疗效观察   总被引:1,自引:0,他引:1  
2003年1月~2005年8月,我们使用正清风痛宁缓释片治疗类风湿关节炎(rheumatoidarthritis,RA)60例,并以甲氨蝶呤作为对照药物,现将结果报道如下。1资料与方法1.1一般资料2003年1月~2005年8月,共收集我院门诊诊断为RA的患者120例,符合美国风湿病协会1987年RA分类标准[1],且至少3  相似文献   
22.
9(S)-红霉胺是合成地红霉素和CP-544372的中间体,此化合物可在超声波的作用下利用NaBH4/ZrCl4于室温下还原9(E)-红霉素肟制得,收率为69%,其结构经IR、NMR和MS确证。该方法是制备9(S)-红霉胺的方便、有效的途径。  相似文献   
23.
The main measure to reduce energy losses is the usage of insulating materials. When the temperature exceeds 500 °C, silicate and ceramic products are most commonly used. In this work, high-crystallinity 1.13 nm tobermorite and xonotlite were hydrothermally synthesized from lime and Ca–Si sedimentary rock, opoka. By XRD, DSC, TG and dilatometry methods, it has been shown that 1.13 nm tobermorite becomes the predominant compound in stirred suspensions at 200 °C after 4 h of synthesis in the mixture with a molar ratio CaO/SiO2 = 0.83. It is suitable for the production of insulating products with good physical–mechanical properties (average density < 200 kg·m−1, compressive strength ~0.9 MPa) but has a limited operating temperature (up to 700 °C). Sufficiently pure xonotlite should be used to obtain materials with a higher operating temperature. Even small amounts of semi-amorphous C–S–H(I) significantly increase its linear shrinkage during firing. It has also been observed that an increase in the strength values of the samples correlated well with the increase in the size of xonotlite crystallites. The optimal technological parameters are as follows: molar ratio of mixture CaO/SiO2 = 1.2; water/solid ratio W/S = 20.0; duration of hydrothermal synthesis at 220 °C—8 h, duration of autoclaving at 220 °C—4 h. The average density of the samples was ~180 kg·m−1, the operating temperature was at least 1000 °C, and the compressive strengths exceeded 1.5 MPa.  相似文献   
24.
An analytical model was developed to determine the temperature of friction coupling, in which one element was made of a functionally graded material (FGM) and the other was homogeneous. First, for such a system, the boundary–value problem of heat conduction was formulated with consideration of the heat generation due to friction. Then, using the Laplace integral transform, an exact solution to this problem was obtained for uniform sliding, and braking with constant deceleration. A numerical analysis was performed for the selected friction pair consisting of the FGM (zircon dioxide + titanium alloy) and cast iron. It was established that the use of elements made of a FGM consisting of ZrO2 and Ti-6Al-4V can significantly reduce the maximum temperature achieved in the friction system.  相似文献   
25.
Granular materials are widespread in nature and human production, and their macro-mechanical behavior is significantly affected by granule movement. The development of computer vision has brought some new ideas for measuring the numerical information (including the amount of translation, the rotation angle, velocity, acceleration, etc.) of dynamic granular materials. In this paper, we propose a numerical measurement method for dynamic granular materials based on computer vision. Firstly, an improved video instance segmentation (VIS) network is introduced to perform end-to-end multi-task learning, and its temporal feature fusion module and tracking head with long-sequence external memory can improve the problems of poor video data quality and high similarity in appearance of granular materials, respectively. Secondly, the numerical information can be extracted through a series of post-processing steps. Finally, the effectiveness of the measurement method is verified by comparing the numerical measurement results with the real values. The experimental results indicate that our improved VIS obtains an average precision (AP) of 76.6, the relative errors and standard deviations are maintained at a low level, and this method can effectively be used to measure the numerical information of dynamic granular materials. This study provides an intelligent proposal for the task of measuring numerical information of dynamic granular materials, which is of great significance for studying the spatial distribution, motion mode and macro-mechanical behavior of granular materials.  相似文献   
26.
目的:对苗药苦针汤进行组方基础研究和新药开发研究。方法:以该方对金黄色葡萄球菌、痢疾杆菌、白色葡萄球菌、致病性大肠杆菌(1)的抑制作用为考察指标,运用混料均匀设计法将组成苦针汤中的4味药配制成12种不同比例的复方,通过抗菌实验,测试用药抗菌能力。结果:建立回归方程.对回归方程及其中各项系数进行检验,求抗菌效果最佳时的变量取值。结论:回归方程通过检验,有意义、可用;苦参、黄芩对抑菌效果的贡献不显著,其余两味药以19.56g和11.84g组方时抗菌效果最佳,优于理论计算值。  相似文献   
27.
内蒙古凤毛菊属药用植物资源调查   总被引:7,自引:0,他引:7  
李君山  赵永华  朱兆仪  金延明 《中草药》1999,30(10):776-780
根据实地调查和分类鉴定研究,结合文献资料,报道了内蒙古凤毛菊属16种、7变种药用植物及其分布、生境、贮藏量、药用价值,并编制了分种检索表。该研究有助于对本属植物的资源利用和深入研究 。  相似文献   
28.
玛咖酰胺研究进展   总被引:1,自引:1,他引:1  
陈金金  赵兵 《中草药》2015,46(21):3284-3288
玛咖因其丰富的营养价值和多样的药用价值被作为食品和传统药材长期食用。玛咖酰胺为其特征性化合物,是一系列非极性长链脂肪酸的氮苄基酰胺类化合物,具有神经保护及神经系统调节等活性。综述了玛咖酰胺的种类,及其化学合成、检测方法、生物活性的国内外研究进展,为进一步研究及开发利用提供参考。  相似文献   
29.
A platform to accelerate optimization of proteolysis targeting chimeras (PROTACs) has been developed using a direct-to-biology (D2B) approach with a focus on linker effects. A large number of linker analogs—with varying length, polarity, and rigidity—were rapidly prepared and characterized in four cell-based assays by streamlining time-consuming steps in synthesis and purification. The expansive dataset informs on linker structure–activity relationships (SAR) for in-cell E3 ligase target engagement, degradation, permeability, and cell toxicity. Unexpected aspects of linker SAR was discovered, consistent with literature reports on “linkerology”, and the method dramatically speeds up empirical optimization. Physicochemical property trends emerged, and the platform has the potential to rapidly expand training sets for more complex prediction models. In-depth validation studies were carried out and confirm the D2B platform is a valuable tool to accelerate PROTAC design–make–test cycles.  相似文献   
30.
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