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31.
Morteza Nazerian Jalal Karimi Hossin Jalali Torshizi Antonios N. Papadopoulos Sepideh Hamedi Elham Vatankhah 《Materials》2022,15(24)
The purpose of the present article is to study the bending strength of glulam prepared by plane tree (Platanus Orientalis-L) wood layers adhered by UF resin with different formaldehyde to urea molar ratios containing the modified starch adhesive with different NaOCl concentrations. Artificial neural network (ANN) as a modern tool was used to predict this response, too. The multilayer perceptron (MLP) models were used to predict the modulus of rapture (MOR) and the statistics, including the determination coefficient (R2), root mean square error (RMSE), and mean absolute percentage error (MAPE) were used to validate the prediction. Combining the ANN and the genetic algorithm by using the multiple objective and nonlinear constraint functions, the optimum point was determined based on the experimental and estimated data, respectively. The characterization analysis, performed by FTIR and XRD, was used to describe the effect of the inputs on the output. The results indicated that the statistics obtained show excellent MOR predictions by the feed-forward neural network using Levenberg–Marquardt algorithms. The comparison of the optimal output of the actual values obtained by the genetic algorithm resulting from the multi-objective function and the optimal output of the values estimated by the nonlinear constraint function indicates a minimum difference between both functions. 相似文献
32.
比较不同分子量羟乙基淀粉对术中血液循环及凝血功能的影响 总被引:2,自引:0,他引:2
目的多中心、双盲、平行对照比较术中输注国产6%羟乙基淀粉200/0.5(6%HES200/0.5,盈源)和6%羟乙基淀粉130/0.4(6%HES130/0.4,万汶)对术中血流动力学、血液流变学及凝血功能的影响。方法150例择期手术的患者随机均分为Y组和V组。手术开始后,Y组输注6%HES200/0.51000ml,V组输注6%HES130/0.41000ml。分别于麻醉前(T0)、输注开始时(T1)、输注开始后30min(T2)、60min(T3)、90min(T4)、120min(T5)各时点监测患者血流动力学参数,在麻醉前及输注结束后10min抽血检测凝血功能及血液流变学参数。结果与T0时相比,两组患者T1时MAP均明显下降(P<0.05),V组T4、T5时MAP明显降低(P<0.05);T3时V组HR增快(P<0.05),输液结束后两组凝血酶原时间(PT)及部分凝血酶原时间(APTT)均有所延长(P<0.05),纤维蛋白原下降(FIB)(P<0.05),血小板计数(Plt)减少(P<0.05),但两组组间差异无统计学意义;两组液体均可降低全血高、低切变率(P<0.05),对血浆粘度无明显作用。两组术中输血量及晶体输入量差异无明显统计学意义。结论输入6%HES200/0.5或6%HES130/0.41000ml均可有效维持血流动力学稳定,改善机体微循环,但对凝血功能均有尚可耐受的影响。 相似文献
33.
目的 :探讨中西药合用对上消化道出血的临床治疗价值及应用规律。方法 :将 1 30例小、中量上消化道出血患者随机分为单用黄蜜浆治疗 (黄蜜浆 )组 4 2例、单用质子泵抑制剂治疗 (质子泵 )组 4 2例及黄蜜浆和质子泵抑制剂联合治疗 (黄蜜泵 )组 4 6例 ,比较 3组的治疗效果和止血时间。结果 :黄蜜泵组痊愈率 (87.0 % )高于质子泵组 (6 9.0 % ,P<0 .0 5 ) ,止血时间〔包括黑便转黄时间和便潜血转阴时间 ,分别为 (36 .5± 1 0 .2 ) h和(2 .5± 0 .9) d〕也明显优于质子泵组〔分别为 (81 .4± 2 5 .5 ) h和 (5 .2± 1 .9) d,P均 <0 .0 1〕和黄蜜浆组〔分别为(5 2 .3± 1 5 .6 ) h和 (3.9± 1 .2 ) d,P均 <0 .0 1〕。结论 :黄蜜浆与质子泵抑制剂联合运用治疗上消化道出血可缩短止血时间 ,提高治疗效果 ,有协同作用 相似文献
34.
目的比较非体外循环冠状动脉搭桥术(0PCAB)中临床剂量的羟乙基淀粉(HES)130/0.4和琥珀酰明胶对凝血功能的影响。方法选择24例美国麻醉医师协会(ASA)分级Ⅱ~Ⅲ级、择期行OPCAB的患者,随机均分为琥珀酰明胶组(GEL组)和HES组。分别于麻醉诱导前(T0)、术毕即时(T1)和术后24 h(T2)测定血小板计数、凝血酶原时间(PT)、活化部分凝血活酶时间(APTT)、纤维蛋白原(Fib)和D-二聚体等凝血功能指标。记录术中失血量、术后24 h内的胸管引流量和输血量。结果两组间手术时间、术中补液量、术中出血量和24 h胸管引流量的差异均无显著性(P值均>0.05)。两组间T0、T1和T2时间点的血小板计数、PT、APTT、Fib及D-二聚体的差异均无显著性(P值均>0.05)。结论临床剂量的HES 130/0.4与琥珀酰明胶对OPCAB患者凝血功能的影响无明显差异,可安全应用于OPCAB的容量治疗。 相似文献
35.
Junxia Yu Huantong Su Shuda Wei Changsheng Liu 《Journal of biomaterials science. Polymer edition》2013,24(14):1716-1728
AbstractBlood coagulates are closely related to calcium ions (coagulation factor IV), and calcium-doped biomaterials have been reported to be effective in hemostasis. However, the effects exerted by calcium on hemostatic agents have not been previously investigated. The aims of this work were to develop calcium-modified oxidized microporous starch (CaOMS) with controllable calcium contents and to explore the relationship between calcium content and hemostatic effects. The results showed that low calcium content promoted coagulation, while high calcium content inhibited coagulation. CaOMS3 with 2.2 mg/g calcium content was optimal because of its excellent water absorption performance that enhanced physical coagulation, the rapid initiation of coagulation cascade reactions, and the enhanced chemical coagulation by RBC aggregation and platelet activation. The synergistic effects of chemical activation and physical absorption endowed CaOMS with the potential to control internal organ bleeding. These results suggested that CaOMS may be a promising hemostatic agent with wide spread applications. 相似文献
36.
Paul M. Young Stephen Edge John N. Staniforth D. Fraser Steele Robert Price 《Pharmaceutical development and technology》2013,18(2):211-216
The relationship between the apparent moisture content and moisture sorption of modified starches was investigated. Samples of sodium starch glycolate (SSG), pregelatinized starch (PGS) and potato starch (PS) were stored for various times at 44% or 75% relative humidity (RH) to produce samples with moisture contents of up to 14%, as determined by loss on drying (LOD). Evaluation of LOD and mass gain data suggested that measured mass gain equated to predicted LOD values for PGS and PS. However, in SSG there was a nonstoichiometric relationship between mass gain and predicted LOD. In addition, samples of SSG displayed hysteresis during dynamic vapor sorption (DVS) cycling in that an apparent mass loss of about 2–3% was observed for two of the SSGs, with PS and PGS exhibiting reversibility. In some cases, SSG exhibited an apparent mass loss during the DVS cycle at with 50% RH. These observations suggest that one or more of the components of SSG “interact” with moisture. Because X-ray diffraction suggested there was no dramatic change in the crystallinity of SSG, an exchange of residual SSG solvent, alcohol, with moisture may, in part, explain the moisture sorption behavior of SSG. 相似文献
37.
《Pharmaceutical development and technology》2013,18(5):570-578
AbstractDry foam technology reveals the opportunity to improve the dissolution behavior of poorly soluble drugs tending to agglomeration due to micronization. In this study, the impact of fillers on the manufacturability, the properties of dry foams and granules as well as the dissolution kinetics of dry foam tablets was investigated using fenofibrate as a model compound. Different maltodextrins and dried glucose syrups, a maltodextrin–phosphatidylcholine complex, isomalt and a 1:1 mixture of mannitol/glucose syrup were used as filler. Within the group of maltodextrins and glucose syrups, the influences of dextrose equivalent (DE), particle morphology and botanical source of starch were investigated. Comparable macroscopic foam structures were obtained with maltodextrins and glucose syrups whereas different foam morphologies were obtained for the other fillers tested. Regarding the maltodextrins and glucose syrups, different physicochemical and particle properties had a minor impact on granule characteristics and tablet dissolution. Using the maltodextrin–phosphatidylcholine complex resulted in a low specific surface area of the granules and a slow tablet dissolution caused by a slow disintegration. In contrast, a high specific surface area and a fast release were obtained with isomalt and glucose syrup/mannitol mixture indicating that high soluble low molecular weight fillers enable the development of fast dissolving dry foam tablets. 相似文献
38.
目的分析阿托伐他汀钙联合羟乙基淀粉注射液对分水岭脑梗死患者急性期和远期临床治疗效果。方法选取本院2013年2月至2014年6月收治的分水岭脑梗死患者78例为研究对象,采用随机数表法将其分为观察组和对照组,每组各39例,两组患者均给予稳压、降糖、抗血小板聚集等常规治疗,对照组患者在此基础上加用阿托伐他汀钙,观察组患者给予阿托伐他汀钙联合羟乙基淀粉注射液,比较两组患者急性期和远期的临床效果。结果治疗后7天,观察组患者日常生活能力和神经功能恢复均明显优于对照组(P<0.05);治疗后3个月,观察组患者神经功能及日常生活能力恢复均明显优于对照组,且治疗总有效率明显高于对照组(χ2=7.47,P<0.01)。结论阿托伐他汀钙联合羟乙基淀粉注射液在分水岭脑梗死患者急性期和远期均有较好的临床治疗效果。 相似文献
39.
《Pharmaceutical development and technology》2013,18(4):466-476
A novel flavonoid-polysaccharide conjugate was synthesized by free radical grafting of quercetin on starch. The covalent insertion of quercetin in the polymeric chain was confirmed by FT-IR, DSC and fluorescence analyses, while an estimation of the amount of quercetin bound per g of polymer was obtained by the Folin-Ciocalteu assay. The conjugate shows improved UV stability and retains the antioxidant properties of free quercetin, such as scavenging activity towards free radicals (DPPH and peroxynitrite); inhibition of the free radical formation (peroxidation of linoleic acid) and total antioxidant activity. The conjugate also prevented drug degradation and shows potential health functionality in the treatment of Alzheimer disease, diabetes and as skin-whitening agent. 相似文献
40.
Shereen M. Assaf Mai Subhi Khanfar Ahmed Bassam Farhan Iyad Said Rashid Adnan Ali Badwan 《Pharmaceutical development and technology》2019,24(6):761-774
It was aimed to investigate the compressibility, compactibility, powder flow and tablet disintegration of a new excipient comprising magnesium (Mg) silicate co-processed (5%–85% w/w) onto chitin, microcrystalline cellulose (MCC) and starch as the hydrophilic polymers of interest. Initially, the mechanism of tablet disintegration was studied by measuring water infiltration rate, moisture sorption, swelling capacity and hydration ability. Moreover, the powders compression behavior was carried out by applying Kawakita model of compression analysis in addition to porosity and radial tensile strength measurements. In vitro drug release of compacts made of 400?mg ibuprofen and 300?mg of the hydrophilic polymers containing 30% w/w Mg silicate co-precipitate was investigated in phosphate buffer (pH 7.8). This work demonstrated that the incorporation of Mg silicate to the hydrophilic polymers lead to the improvement of powder flowability, compactibility, stability (with regard to storage conditions), compacts crushing strength, and disintegration time in addition to faster drug release. The overall findings are practically advantageous in the context of finding a low cost and multifunctional co-processed excipient of natural origins. 相似文献