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91.
目的建立高效液相色谱法测定复方矮地茶止咳合剂中槲皮素和山奈酚的含量。方法采用SUPELCO Discovery C18(4.6mm×250nm,5μm)色谱柱,流动相:甲醇-0.4%磷酸溶液(50:50),流速:1.0mL·min^-1,检测波长:370nm,柱温:40℃,进样量:10μL。结果槲皮素和山奈酚分别在6.484-155.6μg·mL^-1、5.708~137.0μg·mL^-1与峰面积线性关系良好,低、中、高3个剂量组的平均回收率分别为93.6%、97.2%、98.2%与95.2%、94.9%、100.2%。结论所建立的方法准确可靠、灵敏度高、专属性强,可有效控制复方矮地茶止咳合剂的质量。 相似文献
92.
《Journal of anxiety disorders》2014,28(7):696-703
Anxiety sensitivity (AS), a multidimensional construct, has been implicated in the development and maintenance of anxiety and related disorders. Recent evidence suggests that AS is a dimensional-categorical construct within individuals. Factor mixture modeling was conducted in a sample of 579 adult smokers (M age = 36.87 years, SD = 13.47) to examine the underlying structure. Participants completed the Anxiety Sensitivity Index-3 and were also given a Structured Clinical Interview for DSM-IV-TR. Three classes of individuals emerged, a high AS (5.2% of the sample), a moderate AS (19.0%), and a normative AS class (75.8%). A cut-score of 23 to identify high AS individuals, and a cut-score of 17 to identify moderate-to-high AS individuals were supported in this study. In addition, the odds of having a concurrent anxiety disorder (controlling for other Axis I disorders) were the highest in the high AS class and the lowest in the normative AS class. 相似文献
93.
94.
Dharmila Panghal Manju Nagpal Gurjeet Singh Thakur Sandeep Arora 《Scientia pharmaceutica》2014,82(1):177-191
The present research was aimed at the enhancement of the dissolution rate of atorvastatin calcium by the solid dispersion technique using modified locust bean gum. Solid dispersions (SD) using modified locust bean gum were prepared by the modified solvent evaporation method. Other mixtures were also prepared by physical mixing, co-grinding, and the kneading method. The locust bean gum was subjected to heat for modification. The prepared solid dispersions and other mixtures were evaluated for equilibrium solubility studies, content uniformity, FTIR, DSC, XRD, in vitro drug release, and in vivo pharmacodynamic studies. The equilibrium solubility was enhanced in the solid dispersions (in a drug:polymer ratio of 1:6) and other mixtures such as the co-grinding mixture (CGM) and kneading mixture (KM). Maximum dissolution rate was observed in the solid dispersion batch SD3 (i.e. 50% within 15 min) with maximum drug release after 2 h (80%) out of all solid dispersions. The co-grinding mixture also exhibited a significant enhancement in the dissolution rate among the other mixtures. FTIR studies revealed the absence of drug-polymer interaction in the solid dispersions. Minor shifts in the endothermic peaks of the DSC thermograms of SD3 and CGM indicated slight changes in drug crystallinity. XRD studies further confirmed the results of DSC and FTIR. Topological changes were observed in SEM images of SD3 and CGM. In vivo pharmacodynamic studies indicated an improved efficacy of the optimized batch SD3 as compared to the pure drug at a dose of 3 mg/kg/day. Modified locust bean gum can be a promising carrier for solubility enhancement of poorly water-soluble drugs. The lower viscosity and wetting ability of MLBG, reduction in particle size, and decreased crystallinity of the drug are responsible for the dissolution enhancement of atorvastatin. The co-grinding mixture can be a good alternative to solid dispersions prepared by modified solvent evaporation due to its ease of preparation and significant improvement in dissolution characteristics. 相似文献
95.
目的:分析研究自拟中药方剂延玉合剂治疗老年稳定劳力型心绞痛的效果及安全性。方法选择2010年8月~2014年2月本院收治的36例老年稳定劳力型心绞痛患者为研究对象,随机分为两组。对照组采用常规抗心绞痛治疗,实验组患者给予抗心绞痛联合中药延玉合剂治疗,对比两组患者的治疗效果。结果实验组患者的总有效为94.44%,明显优于对照组(66.67%),差异有统计学意义(P〈0.05);实验组患者的运动持续时间长于对照组,差异有统计学意义(P〈0.05)。结论自拟中药方剂延玉合剂治疗老年稳定劳力型心绞痛的效果较好,值得应用。 相似文献
96.
目的 研究注射用三磷酸腺苷辅酶胰岛素(能量合剂)对心肌缺血再灌注损伤所导致的心肌梗死大鼠的保护作用。方法 结扎左冠状动脉前降支60 min 后进行再灌注,与正常Ⅱ导联心电图(ECG-Ⅱ)比较,冠脉结扎后10 min,ECG-Ⅱ的ST 段抬高0.2 mV 以上者作为缺血成功;再灌注后10 min,ECG-Ⅱ中抬高的ST 段下降30%以上者作为再灌注成功。造模成功后随机分为模型组,能量合剂组(3.6 mg·kg-1·d-1);另设8 只大鼠作为假手术组。给药30 d 后测定彩色多普勒超声心动图、血流动力学、心肌梗死范围;ELISA 法检测血清丙二醛(MDA)、超氧化物歧化酶(SOD)、肌酸激酶同工酶(CK-MB)、肌酸脱氢酶(LDH)及心肌肌钙蛋白(cTnT)的表达。结果 能量合剂可以改善心肌梗死大鼠的左心室功能,明显提高左心室的射血分数、降低左室舒张末压,减少心肌梗死范围,表明能量合剂能清除氧自由基,减少脂质过氧化产物的生成,从而起到保护损伤心肌的作用。结论 能量合剂对心肌缺血再灌注损伤所导致的心肌梗死具有一定的保护作用。 相似文献
97.
The type and fineness of a filler significantly affect the performance of an asphalt mixture. There is a lack of specific research on the effects of filler fineness and dust from aggregates on the properties of epoxy asphalt (EA) mixtures. The effects of aggregate dust and mineral powder on the properties of an EA mixture were evaluated. These filler were tested to determine their fineness, specific surface area and mineral composition. The effects of these fillers on the EA mastic sample and mixture were evaluated. The morphology of the EA mastic samples was analyzed using scanning electron microscopy (SEM). The effects of the fillers on the Marshall stability, tensile strength and fatigue performance of the EA mixture were evaluated. The dust from the aggregates exhibited an even particle size distribution, and its average particle size was approximately 20% of that of the mineral powder. The SEM microanalysis showed that the EA mastic sample containing relatively fine dust formed a tight and dense interfacial bonding structure with the aggregate. The EA mixture sample containing filler composed of dust from aggregate had a significantly higher strength and longer fatigue life than that of the EA sample containing filler composed of mineral powder. 相似文献
98.
Improper handling of waste printed circuit boards (PCBs) can cause serious pollution to the water and soil environments. In order to explore a new method of recycling waste PCBs, this study investigated the effect of PCBs and butadiene styrene rubber (SBR) on the rheological properties of neat bitumen. The dynamic shear rheological (DSR) test was used to study the effect of different PCB contents on the high-temperature rheological properties of SBR-modified bitumen. Fluorescence microscopy and Fourier-transform infrared spectroscopy were used to study the microstructure change law and modification mechanism of PCB and SBR composite modified bitumen. Finally, the feasibility of the bitumen properties was verified through a test of the bituminous mixture properties. The DSR test results showed that the addition of PCBs improves the elastic recovery modulus, dynamic shear modulus, and rutting factor of SBR-modified bitumen, indicating that the high-temperature properties were improved. Infrared spectroscopy analysis revealed that a new absorption peak was generated in the infrared spectrum of the compound bitumen after the addition of PCBs, and the intensity of the original absorption peak also changed, indicating that PCBs and SBR-modified bitumen were mainly physically blended and accompanied by a weak chemical reaction. It was further found that the absorption peak of the unsaturated C=C double bond was significantly enhanced, and the increase in the content of the unsaturated bond C=C in the main chain of the polymer significantly increases the stiffness of the bitumen. Macroscopically, the high-temperature rutting resistance was improved to a certain extent. The fluorescence diagram shows that when PCBs do not exceed 10%, the PCBs can form a homogeneous structure and be dispersed in SBR-modified bitumen. The road test of PCBs and SBR composite modified bituminous mixtures showed that PCBs can significantly improve the rutting resistance and water stability of SBR-modified bitumen at high temperatures at the recommended optimum content. The crack resistance at low temperatures is weakened but still meets actual engineering requirements. The correlation analysis between the properties of bitumen and bituminous mixtures is carried out based on grey correlation theory. The results show that the index of modified bitumen has a very good guiding effect on the bituminous mixture properties. The development of PCBs and SBR composite-modified bitumen provides a new practical method for recycling waste PCBs. 相似文献
99.
Recycling of reclaimed asphalt pavement (RAP) has gradually emerged as a hot topic in the current research of building materials. Manufacturing the recycled asphalt mixture with a high RAP content still remains a major challenge due to the problem of inferior water damage resistance and fatigue cracking resistance. The aim of this study is to evaluate the servicing performance of recycled asphalt mixture with high percentage of RAP and assess its environmental impact on volatile organic compounds (VOCs) emission. To further explore the intrinsic factor on the performance of a recycled asphalt mixture, the mixed asphalt binder with a different content of extracted RAP binder was firstly investigated. The results show that the larger the content of RAP binder, the lower the mechanical indexes and VOCs emission. There exists an internal relationship between the chemical composition and VOCs release behavior with the variation of the recycled asphalt binder content. Based on the results of mixed recycled asphalt binder, the road servicing performance of a rather high utilization of RAP (i.e., 50%, 60%, and 70%) was assessed. It was found that the reuse of RAP aggregates has little influence on the volume performance of recycled asphalt mixture, and servicing performances still meet the construction requirements in spite of a descending trend. Moreover, a significant reduction effect on VOCs emission was found in the mixing stage of recycled asphalt mixture, indicating that the VOCs emission can be decreased by 94.82% when the content of RAP aggregates increases to 70%. The recycling of RAP with a high content contributes to the sustainable development of road engineering and the construction of green pavements. 相似文献
100.
Kate Bibbings Peter J. Harding Ian D. Loram Nicholas Combes Emma F. Hodson-Tole 《Ultrasound in medicine & biology》2019,45(5):1164-1175
Diagnosis of motor neurone disease (MND) includes detection of small, involuntary muscle excitations, termed fasciculations. There is need to improve diagnosis and monitoring of MND through provision of objective markers of change. Fasciculations are visible in ultrasound image sequences. However, few approaches that objectively measure their occurrence have been proposed; their performance has been evaluated in only a few muscles; and their agreement with the clinical gold standard for fasciculation detection, intramuscular electromyography, has not been tested. We present a new application of adaptive foreground detection using a Gaussian mixture model (GMM), evaluating its accuracy across five skeletal muscles in healthy and MND-affected participants. The GMM provided good to excellent accuracy with the electromyography ground truth (80.17%–92.01%) and was robust to different ultrasound probe orientations. The GMM provides objective measurement of fasciculations in each of the body segments necessary for MND diagnosis and hence could provide a new, clinically relevant disease marker. 相似文献