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《中国生物制品学杂志》2015,(7)
目的探讨枸杞多糖对亚健康小鼠机体免疫功能及抗疲劳作用的影响及其作用机制。方法采用复合因素建立亚健康小鼠模型,随机分为模型组、枸杞多糖高剂量组(400 mg/kg体重)和低剂量组(200 mg/kg体重),另设对照组(未建模),经小鼠灌胃给药,每天1次,灌胃21 d,对照组和模型组给予等量蒸馏水。对建模小鼠进行行为学评价;检测各组小鼠的免疫功能(脾脏和胸腺指数、T和B淋巴细胞增殖能力及CD4+/CD8+值)和抗疲劳能力(游泳力竭时间、下丘脑5-羟色胺(5-hydroxytryptamine,5-HT)和多巴胺(Dopamine,DA)含量及海马区谷氨酸受体NR2A m RNA表达水平)。结果模型小鼠体重、自主活动次数、挣扎时间及游泳力竭时间明显低于对照组(P0.05),避暗穿梭次数明显高于对照组(P0.05)。模型组小鼠的胸腺、脾脏指数、B淋巴细胞增殖能力、CD4+/CD8+值、游泳力竭时间、下丘脑DA含量及海马区NR2Am RNA的表达均显著低于对照组(P0.05),5-HT含量明显高于对照组(P0.05);枸杞多糖高剂量组小鼠胸腺指数、脾脏指数、B淋巴细胞增殖能力、CD4+/CD8+值、游泳力竭时间、下丘脑DA含量及小鼠海马NR2A m RNA的表达均显著高于模型组(P0.05),且5-HT含量明显低于模型组(P0.05);各组间T细胞增殖能力无明显变化。结论成功建立亚健康小鼠模型,枸杞多糖可提高亚健康模型小鼠的免疫功能及抗疲劳作用,为枸杞多糖的临床应用提供了实验依据。 相似文献
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为探究桦褐孔菌发酵液作为化妆品原料的安全性及功效性,以多次皮肤刺激性试验、人体斑贴试验对桦褐孔菌发酵液的安全性进行评价;通过斑马鱼胚胎模型及14天人体试用验证桦褐孔菌发酵液的舒缓、修护功效。结果显示,体积分数63%的桦褐孔菌发酵液对斑马鱼胚胎中性粒细胞的聚集抑制率为35%,对其损伤尾鳍生长促进率为16%;桦褐孔菌发酵液喷雾人体使用14 d后,皮肤角质层水分含量、血红素指数、皮肤红度较对照组均有显著改善(P<0.05);安全试验及人体试用均无任何皮肤刺激反应,表明其具有良好的安全性。 相似文献
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目的研制既具备药理作用又健康美味的桦褐孔菌压片糖果,并使用正交试验设计对其制备工艺进行优化。方法以桦褐孔菌粉末为原料,对影响压片糖果质量的因素进行单因素考察,在此基础上,选取桦褐孔菌用量,稀释剂(MCC∶乳糖)比例,阿拉伯半乳糖,酵母β葡聚糖设计4因素3水平的正交实验,采用综合加权评分法,得到最佳处方。结果正交试验优化后最佳工艺:桦褐孔菌添加量25%,稀释剂MCC∶乳糖为1∶2.5,阿拉伯半乳糖添加量为10%,酵母β葡聚糖为1.3%,硬脂酸镁添加量为1%,三氯蔗糖添加量为0.15%。结论试验研制的桦褐孔菌压片糖果既保证了产品质量又健康美味,具有良好的市场前景。 相似文献
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目的建立金黄色葡萄球菌(简称金葡菌)荚膜多糖型CP8菌小鼠全身感染模型,并对模型进行免疫攻毒保护性评价。方法金葡菌荚膜多糖型CP8国际标准株49525经37℃培养24 h,用PBS缓冲液稀释成不同浓度菌液,分组经腹腔注射感染BALB/c小鼠,观察小鼠发病症状,统计生存率及体重变化,确定每只小鼠的致死剂量及亚致死剂量;采集不同感染时间的小鼠血液及心脏、肝脏、脾脏、肺、肾脏,进行细菌定植量检测及主要脏器病理学检查。用CP8多糖-蛋白偶联物(实验组)及氢氧化铝佐剂(对照组)对建立的小鼠模型进行3次免疫攻毒保护性实验,统计小鼠存活率。结果经腹腔感染途径建立的小鼠模型,每只致死剂量为3. 0×10~9 CFU,亚致死剂量为1. 5×10~9CFU。感染发病小鼠表现为翘毛弓背、耸肩及行动迟缓,生存率及体重随感染剂量增加明显下降,血液及心脏、肝脏、脾脏、肺、肾脏均有细菌定植,心脏、肾脏、肝脏主要脏器中可见明显细胞坏死和炎性细胞浸润。与对照组比较,实验组小鼠3次攻毒存活率差异均有统计学意义(P均0. 01),对小鼠的保护率分别为55. 6%、50. 0%和57. 1%。结论成功建立金葡菌荚膜多糖型CP8菌小鼠全身感染模型,并可用于疫苗保护性评价,为进一步研究多抗原组分疫苗的有效性和安全性奠定了实验基础。 相似文献
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Dinesh Singh J. K. Gehlawat Musti S. Rao 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1990,47(2):127-136
Oslefins and diolefins are important intermediates in the petrochemical industry and the future promises a further substantial increase in demand. While several catalysts have been formulated in the past for the abstraction of hydrogen from butenes and propylene, these catalysts are inefficient in the abstraction of first hydrogen from butane. Bismuth molybdates (β and γ-phases) containing iron oxide and supported on alumina are used as catalysts in the present investigation on the oxidative dehydrogenation of n-butane. Effects of catalyst content, temperature and oxygen: n-butane ratio on conversion and selectivity to butadiene and (C4H8 + C4H6) are studied in the following ranges of experimental conditions: β-bismuth molybdate/100 mol support I(K), 3–9; γ-bismuth molybdate/100 mol support I(K), 5-20; temperature, 400–500°C; O2: butane ratio, 0.6:1.7. 相似文献
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A viscometer used to measure the viscosity of 10 μl of a liquid, must be miniaturized down, and the liquid velocity gradient in the channel used to determine the viscosity coefficient. Two major factors that affect the liquid velocity are the mechanical forces exerted by the mechanical motors and electromagnetic forces. In this study, electrowetting on dielectric (EWOD) is adopted to drive liquids. Variously sized electrodes on a chip, and two shapes of channel are employed to measure the velocity gradient to determine the viscosity coefficient. The device is fabricated by microelectromechanical system (MEMS) technology. The dielectric layer used in EWOD has a high dielectric constant, BST (Ba0.7Sr0.3TiO3), to reduce the required applied voltage; its surface is coated with hydrophobic polymer, polytetrafluoro-ethylene (PTFE, Teflon® AF DuPont). Experimental results demonstrate that liquids can be pulled at 660 μm/s in linear channels by applying a voltage of 15 V. 相似文献
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考登钢作为一种高耐候结构钢,广泛应用于各个领域。在火力发电方面,考登钢主要应用在工作环境比较恶劣的烟气加热器和空气预热器中。考登钢表面涂搪的目的就是进一步提高其耐腐蚀性能,延长使用寿命。为了提高考登钢元件的使用寿命,对考登钢表面涂搪瓷的可行性、密着性能、瓷釉、工艺控制、质量保证等方面进行了研究。 相似文献
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研究了温度和pH值对漆酶酶活以及漆酶处理纤维压制纤维板性能的影响。结果表明,pH较低、温度较高时漆酶酶活较高,压制的纤维板强度性能较好。但温度太高(60~80℃),延长加热时间,漆酶稳定性变差,酶活明显降低,压制纤维板的强度下降。 相似文献
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In reexamining medium effects on photochemical reactions, we have emphasized those on unequilibrated excited species such as the Franck-Condon species. Despite recent advances in femtochemistry, such a discussion in molecular photochemistry is uncommon, and the problem remains challenging on account of the extremely short-lived excited species. However, in such cases, a small perturbation resulting from, for example, weak guest-host interactions could turn into a determining factor in dictating the course of a photochemical channel of deactivation. Examples of medium-directed diabatic processes have been examined with this idea in mind. A modified view on rhodopsin photoisomerization is presented along with the consideration that confinement does not necessarily lead to inhibition of reactions of the trapped substrate. 相似文献
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采用密度泛函理论(DFT)考察了丙烷在Pt(111)表面上脱氢生成丙烯的反应机理。通过在Pt(111)面上预吸附一定数量H原子模拟共吸附H对丙烷脱氢过程的影响。结果表明:H共吸附能降低丙烷及其脱氢产物的吸附能,促进丙烯脱附,有利于提高丙烯的选择性;H共吸附会导致丙烷脱氢能垒变大,降低催化剂的脱氢活性;共吸附的影响随着H覆盖率增加而增大。 相似文献