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51.
OBJECTIVE To prepare atropine sulfate ophthalmic gel solution.METHODS The gel solution in which carbomer-940 was taken as a increase viscosity was prepared.The quality control methods for acidity and alkalinity,hygienic,determination etc were established. 相似文献
52.
目的:测定红芪多糖3(HPS-3)中4个组分的绝对分子量,相对分子质量分布,均方根旋转半径(Rg),多分散系数(Mw/Mn)等分子特征参数,以均方根旋转半径(Rg)对重均分子量(Mw)作图,计算4个组分在溶液状态的构象。方法:采用凝胶渗透色谱-多角度激光散射(GPC-MALLS)联用技术,流动相为含0.02%NaN3的0.1 mol.L-1NaNO3溶液,Ultrahydro-gelTM1000,500色谱柱串联。结果:HPS-3的4个组分中,HPS-3-C的Mw最大(1.986×105g.mol-1);其次为HPS-3-B(1.113×105 g.mol-1)和HPS-3-D(8.457×104 g.mol-1);HPS-3-A的Mw最小(1.223×104 g.mol-1),而Rg最大(55.5 nm)。HPS-3-D相对分子质量分布范围最广,Mw/Mn 2.543。在流动相中,HPS-3-A为球型构象,HPS-3-C为无规则线团构象,HPS-3-B和HPS-3-D则均为高枝化度结构。结论:为进一步研究HPS-3中4个组分分子特征与其生物活性的关系提供必要依据。 相似文献
53.
微粉硅胶用于白芷提取物粉体改性及其促进元胡止痛分散片崩解的原理研究 总被引:4,自引:0,他引:4
目的 研究微粉硅胶用于白芷提取物粉体改性及其促进元胡止痛分散片崩解的原理.方法 采用混合与液相分散两种方法,微粉硅胶3%、5%、7%3种改性剂量对白芷提取物进行粉体改性,研究粉体改性前后在红外光谱、比表面积与孔隙度、接触角、差示扫描量热、扫描电镜的差异及其对元胡止痛分散片崩解时间的影响.结果 红外光谱显示液相分散法与混合法的改性方式相同,均属物理改性;改性后,粉体的比表面积与孔隙体积显著增加,接触角显著降低,热效应显著变化;当微粉硅胶用量达到5%时,两种方法均能改善元胡止痛分散片的崩解性能.结论 增强白芷提取物比表面积,增强吸水性、润湿性,分散提取物,降低黏性可能是微粉硅胶改性及促进分散片崩解的主要机制. 相似文献
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56.
Valentina Hernndez Davor Ibarra Johan F. Triana Bastian Martínez-Soto Matías Faúndez Diego A. Vasco Leonardo Gordillo Felipe Herrera Claudio García-Herrera Alysia Garmulewicz 《Materials》2022,15(11)
This article focuses on agar biopolymer films that offer promise for developing biodegradable packaging, an important solution for reducing plastics pollution. At present there is a lack of data on the mechanical performance of agar biopolymer films using a simple plasticizer. This study takes a Design of Experiments approach to analyze how agar-glycerin biopolymer films perform across a range of ingredients concentrations in terms of their strength, elasticity, and ductility. Our results demonstrate that by systematically varying the quantity of agar and glycerin, tensile properties can be achieved that are comparable to agar-based materials with more complex formulations. Not only does our study significantly broaden the amount of data available on the range of mechanical performance that can be achieved with simple agar biopolymer films, but the data can also be used to guide further optimization efforts that start with a basic formulation that performs well on certain property dimensions. We also find that select formulations have similar tensile properties to thermoplastic starch (TPS), acrylonitrile butadiene styrene (ABS), and polypropylene (PP), indicating potential suitability for select packaging applications. We use our experimental dataset to train a neural network regression model that predicts the Young’s modulus, ultimate tensile strength, and elongation at break of agar biopolymer films given their composition. Our findings support the development of further data-driven design and fabrication workflows. 相似文献
57.
带蒂颊肌瓣鼻底转移术与硅胶鼻底植入术治疗萎缩性鼻炎的疗效比较 总被引:1,自引:0,他引:1
目的:比较带蒂颊肌瓣鼻底转移术与硅胶鼻底植入术治疗萎缩性鼻炎的疗效。方法:将80例萎缩性鼻炎患者分为2组,43例行带蒂颊肌瓣鼻底转移术(A组),37例行硅胶鼻底植入术(B组)。结果:手术治疗后总有效率A组高于B组(P<0.05),术后并发症A组少于B组(P<0.05)。结论:带蒂颊肌瓣鼻底转移术治疗萎缩性鼻炎具有更好的疗效。 相似文献
58.
Q. R. Li C. Y. Wang C. Tang Q. He N. Li J. S. Li 《American journal of transplantation》2013,13(4):899-910
It has been known that the gut microbiota plays a central role in shaping normal mucosal immunity, however, little information is available whether the variability of mucosal lymphocytes impacts the commensal flora. Here, we applied a cynomolgus monkey model to characterize the structure and composition of the gut microbiota in response to lymphocyte depletion and to determine their potential association. Molecular profiling of 16S rDNA showed that the intestinal microbiota composition was perturbed after the depletion of mucosal lymphocytes and were recovered following the repopulation. Some specific bacteria from the orders Lactobacillales, Enterobacteriales and Clostridiales, and the genus Prevotella and Faecalibacterium, were primarily responsible for the variations of the gut microbiota after lymphocyte depletion. Interestingly, the species richness of the ileal mucosal microbiota was associated the proportions of TCRαβ+ or TCRγδ+ T cells (p < 0.01). We demonstrate for the first time the feature of intestinal microbiota composition after lymphocyte depletion and provide novel evidence that the perturbation of gut microbiota is associated with lymphocyte depletion. It may contribute to understand the relationship between gut commensal microbiota and mucosal immune system. Study results provide insight into biological activity of alemtuzumab in intestinal barrier in organ transplantation. 相似文献
59.
目的 探讨分析采用不同方式清除聚丙烯酰胺水凝胶的适应症和手术方法.方法 对212例患者针对不同病情及要求,采取经乳晕切口单纯清除注射材料、清除材料同时行假体植入、清除材料同时行乳房提升、经乳腔镜清除材料等不同手术方式进行处理.结果 212例患者中单纯经乳晕切口清除139例,乳腔镜清除15例,同期植入假体46例,行乳房提升12例.大部分患者效果满意.结论 注射聚丙烯酰胺水凝胶患者要求清除者,应根据患者的具体注射情况及不同要求,在充分进行术前评估的基础上,采用合理方法进行处理,尽可能减少材料残留,达到满意效果,恢复乳房美观形态. 相似文献
60.
Aiman A. Bin Mokaizh Jun Haslinda Shariffuddin Abdullah O. Baarimah Amin Al-Fakih Abdullah Mohamed Salem O. Baarimah Al-Baraa Abdulrahman Al-Mekhlafi Hamoud Alenezi Olusegun Abayomi Olalere Anwar Ameen Hezam Saeed 《Materials》2022,15(9)
Aluminum waste-can management in Malaysia has recently become a serious environmental and public health issue, particularly in metropolitan areas. This has prompted the need to valorize these waste-cans into value-added products using the most economical and environmentally friendly techniques. In this study, the sol–gel technique was used to synthesize high-quality alumina from the aluminum waste-cans collected. From this method, the observed peaks of the synthesized alumina were identified as diaspore (α-AlO(OH)), boehmite (γ-AlO(OH)), aluminum oxide, or gamma-alumina (γ-Al2O3) crystalline structure and corundum. The morphological configuration, microstructure, and functional group properties of the synthesized alumina were evaluated. All the synthesized alumina exhibited a non-spherical shape and appeared to have hexagonal-like shape particles. Moreover, the XRD patterns of the synthesized alumina AL-6-30 and AL-12-30 exhibited a small angle (1–10°) with no XRD peak, which indicated a mesoporous pore structure with no long-range order. The overall results of γ-alumina synthesized from the aluminum waste-cans showed an optimal condition in producing a highly structured γ-alumina with excellent surface-area characteristics. The synthesized alumina exhibited stronger and highly crystalline functional characteristics almost comparable with the commercially available brands on the market. 相似文献