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采用单因素分析结合正交试验的方法,研究了金莲花黄酮微波辅助提取的工艺条件,以清除DPPH自由基法,对金莲花黄酮的抗氧化性进行了分析,并比较了金莲花黄酮、VC和BHT的抗氧化能力.实验结果表明:微波辅助提取金莲花黄酮的最佳工艺条件是体积分数60%乙醇为溶剂,每克料浸提剂体积为20 mL,微波功率600 W,温度60℃,提取时间2 min.在此工艺下,金莲花黄酮提取率为83.7%;金莲花黄酮能有效地清除DPPH自由基,具有较强的抗氧化能力,与VC>和>BHT相比,其抗氧化能力为VC金莲花黄酮BHT.另外,研究发现金莲花黄酮与VC和金莲花黄酮与BHT均具有一定的抗氧化协同效应. 相似文献
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研究了超声波辅助提取苹果渣中多酚的工艺,利用二次回归正交旋转组合设计考察了乙醇体积分数、料液质量体积比、提取温度、提取时间对苹果渣中多酚物质提取率的影响;试验结果表明,各因子对提取率的影响大小依次是提取温度>料液质量体积比>提取时间>乙醇体积分数;最佳提取工艺条件是:乙醇体积分数50%、料液比1 g:20 mL、提取温度60℃、提取时间24min;此条件下苹果多酚的提取率为3.80 mg/g. 相似文献
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利用正交试验法探索乙醇提取花椒油树脂的最佳工艺条件.结果表明,乙醇提取花椒油树脂最佳实验室条件为:原料粒度过60目筛,乙醇体积分数55%,提取温度60 ℃,固液质量体积比1 g∶12 mL,提取时间为60 min,在提取次数为一次的情况下,花椒油树脂干基得率可达32.50%. 相似文献
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以罗非鱼的鱼内脏为研究对象 ,采用钾盐蒸煮法从罗非鱼内脏中提取鱼油的工艺条件和纯化不饱和脂肪酸 (PUFA)的方法 ,对精制鱼油的氧化性及人工合成抗氧化剂 (TBHQ)、VE、茶多酚 3种抗氧化剂对鱼油的抗氧化性能进行了研究 .通过正交试验及对比试验 ,结果表明 ,从罗非鱼内脏中制取鱼油的最佳工艺条件 :水解温度 70~ 80℃ ,水解时间 4 0min ,KNO3用量 6 g/dL ,盐析时间 10min ;采用低温 钾盐乙醇法纯化鱼油PUFA的效果比尿素包埋法好 ;TBHQ、VE、茶多酚 3种抗氧化剂对鱼油抗氧化作用以茶多酚效果最好 相似文献
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以苹果品种"瑞林"为试材,通过正交试验比较研究了超声波辅助法与传统溶剂法提取苹果果肉中原花青素的效果,经筛选优化了苹果原花青素提取的技术参数.结果表明:超声波辅助法提取苹果果实中的原花青素的最佳条件为:乙醇体积分数50%、PH值为4、温度70℃.在此条件下提取2 h后,原花青素的最大提取量为0.14 mg/g;传统溶剂法提取苹果中原花青素的最佳条件为乙醇体积分数80%、pH值为4、温度90℃.在此条件下提取2 h后,原花青素的最大提取量为0.126 mg/g.利用超声波辅助增强了苹果果肉中原花青素的乙醇提取效果,即降低了提取温度,减少了溶剂用量,并使提取量增加了10.9%. 相似文献
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采用双频超声技术提取海金沙黄酮,选择乙醇体积分数、溶剂体积、超声作用时间、浸泡时间等因素进行正交实验,得出影响总黄酮提取率的因素次序为:乙醇体积分数〉溶剂体积〉超声作用时间〉浸泡时间,双频超声提取最佳工艺条件为:乙醇体积分数为70%,乙醇体积为40mL,超声作用时间为30min,浸泡时间为4h。在此条件下,总黄酮提取率为86.25%。在相同的条件下,与单频超声提取方法相比较,具有溶剂用量少,提取效率高,提取时间短等优点。 相似文献
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《风湿病与关节炎》2015,(9)
目的:对透骨消痛胶囊的提取工艺进行研究,筛选出最佳的工业化提取工艺。方法:采用L9(34)正交表,以浸膏率、阿魏酸、水晶兰苷、芍药苷含量为指标,以乙醇浓度、固液比、提取次数、提取时间为考察因素,优选川芎的提取工艺以及巴戟天和白芍两药材合并的提取工艺,并通过二者最终优化工艺的验证结果与改良工艺试验结果的综合比较,确定适合工业化生产的最佳提取工艺。结果:改良工艺后,指标成分含量变化较小,提取次数与乙醇浓度减少,总浸膏得率降低。因此,综合优化的提取工艺是3药材合并,用10倍质量分数为30%的乙醇加热回流提取2次,每次1.5 h。结论:综合优化的提取工艺合理、可行,适用于透骨消痛胶囊的工业生产。 相似文献
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探索了用乙醇回流法从栽培管花肉苁蓉中提取苯乙醇苷类物质的工艺流程.通过单因素和响应面实验,对影响苯乙醇苷提取的因素进行了探讨和研究,运用响应面分析法确定了提取工艺的最优化条件:提取温度为60 ℃,料液比(g:mL)为1:12.8,提取时间为3.75 h,乙醇体积分数为68.2 %,提取次数2次.在此条件下苯乙醇苷的得率为5.76 %. 相似文献
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采用压榨法、溶剂浸提法、分子蒸馏法、超临界法提取了野香苏籽油.应用尿素包合技术对野香籽油中不饱和脂肪酸进行了富集,通过正交实验(L934)考察了尿素在乙醇中质量浓度、脂肪酸与(尿素 乙醇)的质量比、时间及温度等因素对不饱和脂肪酸提取率的影响.4种提取方法的出油率分别为36.6%,36.5%,26.7%,37.0%,其主要成分是α-亚麻酸.实验确定的最佳提取工艺条件为:尿素质量浓度为1.00 g/mL,脂肪酸与(尿素 乙醇)的质量比为1∶1. 8,回流温度为73~78 ℃,时间为40 min. 相似文献
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胸腰椎骨折椎弓根内固定断裂与植骨融合方式的相关性分析 总被引:9,自引:0,他引:9
[目的]探讨胸腰椎骨折椎弓根螺钉内固定系统内固定术后,椎弓根螺钉断裂与植骨融合方式之间的关系,以探讨胸腰椎骨折植骨融合的最佳方式。[方法]回顾性研究1995年5月~2005年12月本院脊柱外科收治的胸腰椎骨折病人197例,其中A组单纯内固定(不植骨)患者14例,B组“H”形椎板植骨21例,C组横突间植骨67例,D组椎间、椎内联合横突间植骨95例。[结果]术后随访6~32个月,内固定断裂12例,其中A组4例,B组3例,C组5例,D组0例,4组中D组内固定断裂率显著低于其他3组(P<0.05)。[结论]椎间、椎体内联合横突间植骨重建脊柱三柱的稳定性,符合人体生物力学原理,能有效降低内固定断裂的发生。 相似文献
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A number of methods are currently employed to assess the functional properties of CFTR channels and their response to pharmacological potentiators, correction of the defective CFTR trafficking, and vectorial introduction of new proteins. Here we review the most common methods used to assess CFTR channel function. The suitability of each technique to various experimental conditions is discussed. 相似文献
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Yimin Qi Chengxin Liu Lei Wu Lei Yang Lei Zhao Chunzhi Jiang Wengbo Yang Yiwen Zeng 《Orthopaedic Surgery》2021,13(5):1596
ObjectiveComplex base fractures of the fifth metacarpal bone and dislocation of the fifth carpometacarpal joint are more prone to internal rotation deformity of the little finger sequence after fixation with a transarticular plate. In the past, we have neglected that there is actually a certain angle of external rotation in the hamate surface of transarticular fixation. This study measured the inclination angle of the hamate surface relative to the fifth metacarpal surface for clinical reference.MethodsIn a prospective single‐center study, we investigated the tilt angle of 60 normal hamates. The study included thin‐layer computed tomography (CT) data from 60 patients from the orthopaedic clinic and inpatient unit from January 2017 to March 2020, including 34 men and 26 women who were 15~59 years old, average 35 years old. The CT data of 60 cases in Dicom format of the hand was input into Mimics and 3‐Matics software for three‐dimensional (3D) reconstruction and measuring the angle α between hamate surface and the fifth metacarpal surface. According to the possible placement of the transarticular plate on the fifth metacarpal surface, we measured the angle β between the hamate surface 1 and the fifth metacarpal surface and the angle γ between the hamate surface 2 and the fifth metacarpal surface.ResultsThe average angle between the hamate surface and the fifth metacarpal surface was 11.66°. The hamate surfaces 1 and 2 have an external rotation angle of 7.30° and 7.51° on average with respect to the fifth metacarpal surface, respectively. There is no statistically significant difference in the angles between the two groups (P > 0.05).ConclusionsThe horizontal angle of the dorsal side of the hamate is different from the back of the fifth metacarpal surface, and the hamate has a certain external rotation angle with respect to the fifth metacarpal surface. No matter how the transarticular plate is placed, the plate always has a certain external rotation angle relative to the fifth metacarpal surface. When the fixation is across the fifth carpometacarpal joint, if the plate does not twist and shape, it will inevitably cause internal rotation of the fifth metacarpal, resulting in internal rotation deformity of the little finger sequence. 相似文献
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静脉输注甘露醇开放血脑屏障对抗生素透过血脑屏障的影响 总被引:2,自引:0,他引:2
目的 通过快速静脉输注甘露醇可逆性开放血脑屏障 (BBB) ,探知此方法能否增加抗生素透过BBB的量 ,在何时达到最高峰 ,其通透量增加后临床上有无不良反应。方法 采用自身配伍设计 ,共 6个样本组。对照组仅使用抗生素 ;其余 5组分别在使用甘露醇前 60、3 0min ,同时使用甘露醇后 3 0、60min使用抗生素 ,各组皆取使用抗生素后 1h的脑脊液测其抗生素浓度。抗生素选用头孢三嗪。结果 测量值经过q检验 ,经 2 0 %甘露醇处理前后的CSF中的头孢三嗪浓度差异有非常显著性。全组患者经临床观察未出现神经系统的不良反应。结论 经静脉快速输注2 0 %甘露醇后可以使透过BBB的水溶性抗生素的量增加 ,两者使用的顺序是在抗生素使用 3 0min内即给予甘露醇快速滴注。该方法不会增加低神经毒性抗生素在中枢神经系统的不良反应。 相似文献
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John W. Braasch 《Journal of Hepato-Biliary-Pancreatic Surgery》1994,1(4):342-348
The historical evolution of the pylorus-preservation resection of the head of the pancreas is traced from the first resections
early in this century to relative standardization of the operation, to a lowering of the operative mortality, and to an interest
in improving nutritional status after resection. There are many theoretical advantages for the function of the upper gastrointestinal
tract after pylorus and gastric preservation, such as maintenance of gastric capacitance and equilibration of osmotic pressure
in gastric digestants, foodstuff digestion and absorption, and bowel motility. After the pylorus-preserving resection, gastric
emptying is normal, pyloric function to prevent duodenal reflux is often normal, and gastric acids and serum levels of duodenal
hormones are at normal levels, whereas after standard pancreatoduodenectomy, all of these are often abnormal. No prospective
blinded studies have been published comparing nutritional values after the two operative procedures, but evidence is presented
of a satisfactory result with regard to gastric capacitance, body weight gain, and lack of postgastrectomy symptoms. An undoubted
advantage of the pylorus-preserving feature is a simplification of the operation. These gains are achieved without increase
in operative mortality, without increase in the incidence of jejunal ulcer, and without theoretical or actual decrease in
value of the procedure as a cancer operation, except in patients with duodenal carcinoma proximal to the ampulla of Vater. 相似文献
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目的:研究下颌牙弓的有效后移量及找寻下颌牙弓移动的后界。方法:选取涉及拔除下颌第三磨牙或下颌第三磨牙缺失的病例18例(男6例,女12例)。采用种植支抗牵引下牙弓向远中,治疗完成时所有病例均明确到达下颌牙弓后界,即下颌第二磨牙远中到达下颌升支前缘软组织交界处。应用治疗前后的曲断片测量下颌第二磨牙远中到升支前缘的距离。结果:下颌第二磨牙后移量为(3.49±1.21)mm;治疗后磨牙后间隙的长度为(4.43±0.97)mm。结论:下颌牙弓可确定性地实现整体后移;最大后移量由磨牙后间隙的长度决定;其最后界止于下颌第二磨牙远中与下颌升支前缘软组织交界处。 相似文献
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Whipple's pancreatoduodenectomy was the standard operation for diseases of the head of the pancreas for more than 40 years,
but the results were vitiated in part by poor gastrointestinal function and malnutrition. Reintroduced in 1978, pylorus-preserving
proximal pancreatoduodenectomy (PPPP) has had an increasing impact on pancreatic surgery as its benefits have been recognized:
improved nutritional status, decreased incidence of postgastrectomy syndromes, and a technically easier operation. Postoperative
mortality rates and 5-year survival rates are comparable with those of the classic Whipple procedure. PPPP is indicated for
most patients with chronic pancreatitis of the pancreatic head. It is also appropriate for patients with periampullary cancer
and for those with pancreatic cancer arising from the lower part of ‘the head and the uncinate process. More than 650 patients
have now undergone PPPP: 31% for chronic pancreatitis and 66% for periampullary and pancreatic cancers. We assess the indications
for PPPP, outline the operation, and review the results. 相似文献