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1.
将32只Wistar大鼠随机分为对照组(口服0.5%羧甲基纤维素钠溶液)以及低剂量(0.3g/kg)、中剂量(0.9g/kg)和高剂量(2.7g/kg)雄黄混悬液处理组,通过4周连续灌胃给服雄黄混悬液;采用高效液相色谱-电化学法测定了大鼠脑组织中单胺类神经递质及其代谢产物的含量,研究了雄黄对大鼠脑组织单胺类神经递质及其代谢产物的影响.结果表明,与对照组比较,雄黄染毒组大鼠脑组织中NE、DOPAC和DA含量均呈增加趋势,而5-HIAA呈降低趋势.雄黄可对大鼠脑组织单胺类神经递质及其代谢产物产生影响,单胺类神经能系统可能是雄黄毒性作用的靶点之一.  相似文献   

2.
荧光法测定SD大白鼠不同脑区的单胺类神经递质   总被引:8,自引:0,他引:8  
以荧光光谱法定量地研究了不同浓度的司考林作用下,鼠脑组织中去甲肾上腺素、多巴胺和5-羟色胺的定量变化,从而表达了中枢神经递质的变化规律.  相似文献   

3.
单胺类神经递质是人体内一类重要的神经递质,其含量测定对于疾病诊断与控制、药物开发与研究及神经学基础研究具有重要意义。生物样品中单胺类神经递质的含量低,基体复杂,选择快速高效的样品前处理方法,是建立高灵敏单胺类神经递质分析方法的关键。该文对近年来生物样品中单胺类神经递质的样品前处理方法的研究进展进行了详细阐述,对单胺类神经递质分析检测方法的新进展进行了介绍,并对其发展趋势进行了展望。  相似文献   

4.
在酸性条件下, 利用高效液相色谱法研究了柴胡皂苷A对抑郁模型大鼠脑中单胺类神经递质及其代谢物含量的影响. 实验结果表明, 柴胡皂苷A可使抑郁型大鼠脑中的高香草酸、去甲肾上腺素、多巴胺及5-羟色胺的含量升高, 这一结果有利于对柴胡皂苷治疗抑郁症的物质基础及相关机理进行更深入了解.  相似文献   

5.
建立了超高效液相色谱-四极杆飞行时间质谱法(UPLC-Q-TOF-MS)对小鼠大脑中的多巴胺(DA)、5-羟色氨(5-HT)、二羟基苯乙酸(DOPAC)和高香草酸(HVA)4种单胺类神经递质的含量进行同时测定。样品以30%乙醇溶液(甲酸调至p H 5.0)匀浆处理后,冷冻离心,过滤。在优化色谱-质谱条件下,采用ESI和APCI复合源,正/负离子扫描方式进行数据采集。4种单胺类神经递质在0.5~1 000μg/L范围内呈良好线性关系,相关系数(r)大于0.999 3,方法的检出限为0.5~5.0μg/L,平均回收率为93.3%~101.8%,相对标准偏差为1.1%~3.3%。该方法具有操作简便、高效快速、回收率良好、灵敏度高、重现性好和准确度高等优点,可用于小鼠脑组织内4种单胺类神经递质的含量测定。  相似文献   

6.
建立了单胺类神经递质的高效液相色谱-电化学检测方法,探讨了大蒜素对百草枯中毒小鼠脑组织内的单胺类神经递质及其代谢产物的影响。健康ICR小鼠随机分为4组:正常对照(Con)组、大蒜素(DAS)组、百草枯染毒(PQ)组和大蒜素治疗(PQ+DAS)组,每组6只。PQ组灌胃PQ 35 mg/kg建立中毒模型,Con组和DAS组灌服同体积生理盐水。DAS组和PQ+DAS组小鼠于造模2、26、50 h后腹腔内各注射1次DAS(25 mg/kg),PQ组和正常组小鼠腹腔内注射等量无菌生理盐水。造模12 h后处死小鼠。收集小鼠脑组织样品并称重,处理后进样。色谱分析采用Acclaim 120 C18(150 mm×2.1 mm,3μm)色谱柱,以离子对缓冲盐溶液-甲醇(93∶7,体积比)为流动相,流速为0.27 m L/min;电化学检测器检测,工作电压为450 m V。结果表明,与正常组和DAS组比较,PQ组部分神经递质水平降低;DAS治疗后能够改变上述生化指标的变化;与PQ组相比,PQ+DAS组神经递质含量增高,差异均具有统计学意义(P0.05)。脑组织样品中5-HT、DA、5-HIAA、DOPAC和HVA低、中、高3水平的加标回收率均为79.8%~112.1%,相对标准偏差(RSD)小于10%。实验表明,大蒜素对百草枯中毒后小鼠体内含量降低的神经递质有明显的上调作用。  相似文献   

7.
应用高效液相色谱法测定小鼠脑组织中8种单胺类神经递质(去甲肾上腺素、肾上腺素、左旋多巴、多巴胺、二羟基苯乙酸、5-羟色胺、5-羟基吲哚乙酸和高香草酸)的含量,并研究其含量随百草枯中毒时间的长短而产生的变化情况。取小鼠36只,分为6组,每组6只。其中一组为对照组,其余5组的小鼠均按30mg·kg-1的剂量给予灌服百草枯,对照组小鼠灌服同体积的生理盐水。按给毒后达到6,12,24,48,72h时,用1%戊巴比妥钠溶液先后将其麻醉并在低温条件下取其脑组织。按1g∶7.5mL的比例在每份脑组织中加入组织匀浆液并匀浆30s,在4℃高速离心2次,每次15min,取其上清液供色谱分析。在Hypeisil GOLD aQ色谱柱(4.6 mm×250 mm,5μm)上,用不同比例的甲醇和30mmol·L~(-1)磷酸二氢钾-磷酸缓冲溶液(pH 4.6)的混合液为流动相进行梯度洗脱,并用荧光检测器测定各组分的峰面积,用外标法定量。上述8种单胺类神经递质的线性范围均在1 000μg·L~(-1)以内,其检出限(3S/N)在0.34~5.26μg·L~(-1)之间。对样品重复测定5次,测得8组分测定值的相对标准偏差(n=5)在0.58%~4.2%之间,加标回收试验得出其回收率在90.8%~106%之间。同时测得了在百草枯染毒后3d内8种单胺类神经递质含量的变化情况,为进一步研究提供可靠依据。  相似文献   

8.
采用基于核磁共振氢谱(1H NMR)的代谢组学方法, 研究了黄连解毒汤(HJD)对高果糖诱导胰岛素抵抗大鼠模型棕色脂肪代谢组的影响. 选取Wistar大鼠32只, 适应7 d后随机分为正常对照组、 模型组、 阳性药物对照组和黄连解毒汤组, 每组8只. 正常对照组给予纯净水喂养, 其它3组给予100 g/L的果糖水喂饲. 28 d后, 4组大鼠除了继续给予100 g/L的果糖水喂养外, 阳性对照组和黄连解毒汤组同时分别给予阿托伐他汀10 mg/(kg·d)和HJD水煎剂3.175 g/(kg·d)灌胃, 正常对照组和模型组给予一定体积的生理盐水灌胃, 整个实验持续56 d. 取各组大鼠棕色脂肪组织(BAT), 采集各组组织提取液的1H NMR谱, 运用主成分分析法(PCA)分析. 与正常对照组相比, 在模型组中乳酸、 胆碱、 磷脂胆碱/甘油磷脂胆碱、 肌酸/肌酸酐、 牛磺酸和肌苷的含量升高, 脂质含量降低; 黄连解毒汤组逆转了模型组中上述各代谢物的变化, 且引起肌醇升高, 均具有统计学意义. 实验结果表明, 黄连解毒汤能够逆转机体能量代谢、 减轻细胞膜受损以及降低肝肾损伤, 初步阐明了黄连解毒汤对胰岛素抵抗状态下棕色脂肪组织代谢的调控作用.  相似文献   

9.
四氢生物蝶呤(BH4)是生物体内单胺类神经递质合成过程中所需要的一种重要辅酶. 文中以Pt-Pd纳米修饰电极作为液相色谱电化学检测器, 采用高效液相色谱-电化学检测和微渗析活体取样技术, 研究了外源性的四氢生物蝶呤对大鼠纹状体中单胺类神经递质的影响. 研究表明外源性的BH4能提高大鼠纹状体中单胺类神经递质多巴胺(DA)、5-羟色胺(5-HT)及其代谢产物5-羟吲哚乙酸(5-HIAA)和高香草酸(HVA)的含量, 并进行了药物动力学分析, 探讨了BH4和单胺类神经递质浓度与时间的变化, 为一些神经疾病的病理学、药理学研究提供了新的分析手段.  相似文献   

10.
采用微量热法测定了大肠杆菌在左金丸、甘露散、茱萸丸和反左金丸水煮液作用下的生长热谱曲线,获得相应的生物热动力学参数,经主成份分析并结合本草文献报道,综合分析左金丸及类方的药性差异,以从生物物理和生物化学的角度,探讨中医经典类方药性差异的客观真实性.实验发现,左金丸及类方的水煮液对大肠杆菌的生长代谢表现出不同的活性作用.寒凉药方左金丸和甘露散不同程度的抑制细菌的生长代谢.温热药方反左金丸和茱萸丸对细菌的生长代谢有不同程度的促进作用.类方之间存在较稳定的药性差异.类方药性主要受生物热动力学参数:第二指数生长期的生长速率常数k2和最大发热功率Pm2的影响.  相似文献   

11.
Despite the beneficial health properties shown by Lebanese saffron, its qualitative and quantitative composition has never been investigated before. In the present study, NMR spectroscopy, together with antioxidant activity assays, were applied to evaluate the chemical composition of saffron samples of different geographical origins (Lebanon, Italy, Iran, and India) and to categorize the Lebanese saffron for the first time. The distinction between Lebanese saffron and that produced in other countries was attributed to its higher linolenic and linoleic fatty acids, glucose and picrocrocin contents. Moreover, spices produced in three different regions of the Lebanese territory have been clearly differentiated. Saffron cultivated in the Qaa region displayed a high glucose, fatty acids and polyphenols content, whereas Hermel saffron exhibited the largest rate of picrocrocin and glycosylated carotenoids. Finally, samples from Baalbeck showed lower rates for the majority of metabolites. Moreover, Lebanese saffron showed a high antioxidant activity in ABTS and DPPH assays. A low dose of saffron extract (10 µg/mL) inhibited the growth of human lung adenocarcinoma cells, probably due to the high polyphenolic content. This study highlights the quality and peculiarity of Lebanese saffron cultivated in Northern Beqaa district and allows for a good discrimination between spices produced in relatively close territory.  相似文献   

12.
Consumers are avoiding the consumption of highly processed foods, aware of the negative effects of the additives or high temperatures used on the biological value of the food. This causes an interest in ways of minimal processing or low-temperature cooking procedures. However, to achieve the desired organoleptic quality, it is necessary to know the relationship between the parameters of the treatments and the type of raw material. The purpose of this study was to investigate the complex effects of traditional cooking and sous vide heat treatment, cold storage time and muscle on the physicochemical and sensory properties of beef. The study material consisted of samples of musculus longissimus thoracis and musculus semitendinosus obtained from beef half-carcasses. The muscles were subjected to traditional cooking in water at 95 °C until the temperature inside the piece reached 65 °C and sous vide treatment at 65 °C for 2 h. The study was performed after 2 and 21 days of cold storage. Instrumental evaluation of texture parameters, color and sensory evaluation of meat was carried out. Meat stored for 21 days was characterized by more favorable TPA test (Texture Profile Analysis) results compared to meat evaluated 48 h post mortem. The study also showed positive effects of sous vide heat treatment on texture parameters and sensory properties (especially on tenderness and palatability), as well as differences in the formation of quality traits between muscles. Given the trends associated with energy-saving technologies, it is desirable to seek the optimal combination of temperature and time of fixation treatments at an acceptable level of quality. The use of low-temperature cooking for as little as 2 h, yields positive results in sensory evaluation of juiciness, tenderness, or palatability.  相似文献   

13.
采用超高效液相色谱-四极杆飞行时间高分辨质谱(UPLC-QTOFMS)联用技术, 对血清前处理进行了考察和优化, 并对液-质联用分析条件进行了优化, 旨在建立用于血清中广谱小分子代谢物分析的高通量强耐用代谢组学方法, 以期满足大批次生物样本数代谢组学研究的要求(样本数≥400个). 通过考察不同有机溶剂沉淀蛋白对血清中蛋白的去除程度及38个代表性标准品化合物的提取效果, 确定采用甲醇/乙腈(体积比1: 9)沉淀蛋白法. 血清和有机溶剂的体积比不小于1: 4时, 达到最佳的沉淀蛋白处理效果, 符合大批量样本测试的要求; 预先冷藏沉淀蛋白的有机溶剂, 涡旋2 min, 超声1 min, 加入有机溶剂后冷冻静置10 min, 可以进一步提高前处理沉淀蛋白和化合物提取的效果. 通过对不同流动相体系和梯度条件的考察, 对液-质联用分析条件进行了优化. 方法学考察结果表明, 本方法重现性、 精密度及稳定性均良好. 对重现性和48 h稳定性数据进行变异系数分析和主成分分析法的多维分析, 证明本方法在代谢组学研究中的可重复性及所得数据的可靠性. 本方法高通量强耐用, 每天可测定100多个血清样本(13 min测定1个样本), 适用于代谢组学研究, 特别是大批次生物样本的代谢组学研究.  相似文献   

14.
Colorectal cancer (CRC) is the third commonest malignancy cancer worldwide. Clear understandings of global metabolic profiling of the normal mucosa and cancer tissues are vitally important to aid optimizing the clinical management strategy and understanding CRC biology. We studied metabolic characteristics of 20 CRC and 20 distant normal mucosa tissues extracts from 20 patients using high resolution 1H NMR spectroscopy in conjunction with multivariate analyses, such as principal component analysis (PCA). Compared with distant normal mucosa tissues, lactate, taurine, ornithine and polyamine were present at significantly higher levels in CRC tissue extracts whereas myo‐inositol was present at significantly lower level. Two metabolites ratios such as myo‐inositol/taurine and myo‐inositol/(ornithine+polyamine) appear to be the most valuable biomarkers for the differentiation CRC from normal mucosa tissues. Our data suggested that HR 1H NMR spectroscopy combined with multivariate analyses is a potentially useful technology for detecting malignant changes in the normal mucosa tissues, the technique may be further exploited for future CRC biomarker research or identification of targets for therapeutic manipulations.  相似文献   

15.
由于纺丝线上PET/PTT复合长丝中各组分受到的纺丝张力差异导致两组分存在潜在的热收缩性差异.从纺丝线下来的成品丝只有通过后道热处理,才能有效释放潜在的热收缩差异,获得理想、可用的卷曲弹性.通过TMA测试了PET/PTT双组分复合弹性长丝及其对应单组分纤维的热收缩性能.同样的外作用力下,PET/PTT纤维的收缩应变更接近PET纤维、远小于PTT纤维.同样预张力约0.2N下,PET/PTT、PET、PTT纤维的收缩应力依次变大.结果表明PET纤维具有较小的收缩应力和较小的收缩应变,PTT纤维具有较大的收缩应力和较高的收缩应变.这导致后道热处理过程中,PTT组分发生强烈的尺寸收缩,并带动收缩较小的PET组分位于纤维外侧并形成更为细密的卷曲.  相似文献   

16.
Protein-polysaccharide covalent complexes exhibit better physicochemical and functional properties than single protein or polysaccharide. To promote the formation of the covalent complex from lactoferrin (LF) and beet pectin (BP), we enhanced the Maillard reaction between LF and BP by using an ultrasound-assisted treatment and studied the structure and functional properties of the resulting product. The reaction conditions were optimized by an orthogonal experimental design, and the highest grafting degree of 55.36% was obtained by ultrasonic treatment at 300 W for 20 min and at LF concentration of 20 g/L and BP concentration of 9 g/L. The formation of LF-BP conjugates was confirmed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and Fourier transform infrared (FTIR) spectroscopy. Ultrasound-assisted treatment can increase the surface hydrophobicity, browning index, 1,1-diphenyl-2-picryl-hydrazyl (DPPH) and 2,2’-azinobis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS) free radicals scavenging activity of LF due to the changes in the spatial configuration and formation of Maillard reaction products. The thermal stability, antioxidant activity and emulsifying property of LF were significantly improved after combining with BP. These findings reveal the potential application of modified proteins by ultrasonic and heat treatment.  相似文献   

17.
热处理对超疏水性含氟丙烯酸酯共聚物膜表面性能的影响   总被引:3,自引:1,他引:3  
以微乳液聚合法和溶液聚合法制备丙烯酸全氟烷基乙基酯和甲基丙烯酸甲酯的共聚物, 以1,1,2-三氟三氯乙烷为溶剂, 采用溶剂挥发成膜法直接制备出超疏水膜, 并研究120 ℃热处理对超疏水膜表面性能的影响. 对于用乳液聚合方法制备的超疏水膜, 随着热处理时间的延长, 滚动角表现出先逐渐增大直至完全不能滚动, 然后重新回复到极小滚动角的特殊变化过程, 而静态接触角只是略微减小, 完全不同于热处理对平滑的含氟聚合物表面接触角的影响. 扫描电镜结果显示, 聚合物膜表面形貌对应出现从微/纳复合粗糙结构到微孔粗化并重新形成微/纳复合多层粗糙结构的变化.  相似文献   

18.
Salvia fruticosa and S. pomifera subsp. calycina are native to Eastern Mediterranean and S. pomifera subsp. pomifera is endemic to Greece. The primary aim of this study was to develop an analytical methodology for metabolomic profiling and to study their efficacy in combating glycation, the major biochemical complication of diabetes. After sequential ultrasound-assisted extraction of 2 g of leaves with petroleum ether and 70% methanol, the volatile metabolites in the petroleum ether extracts were studied with GC-MS (Gas Chromatography-Mass Spectrometry), whereas the polar metabolites in the hydroalcoholic extracts were determined and quantified by UHPLC-DAD–ESI-MS (Ultra-High Performance Liquid Chromatography–Diode Array Detector–Mass Spectrometry). This methodology was applied to five populations belonging to the three native taxa. 1,8-Cineole was the predominant volatile (34.8–39.0%) in S. fruticosa, while S. pomifera had a greater content of α-thujone (19.7–41.0%) and β-thujone (6.0–39.1%). Principal Component Analysis (PCA) analysis of the volatiles could discriminate the different taxa. UHPLC-DAD-ESI-MS demonstrated the presence of 50 compounds, twenty of which were quantified. PCA revealed that not only the taxa but also the populations of S. pomifera subsp. pomifera could be differentiated. All Salvia samples inhibited advanced glycation end-product formation in a bovine serum albumin/2-deoxyribose assay; rosmarinic and carnosic acid shared this activity. This study demonstrates the antiglycation activity of S. fruticosa and S. pomifera extracts for the first time and presents a miniaturized methodology for their metabolomic profiling, which could aid chemotaxonomic studies and serve as a tool for their authentication and quality control.  相似文献   

19.
热处理对化学沉积Ni-Fe-P合金性能的影响   总被引:3,自引:0,他引:3  
采用DSC和XRD研究了化学镀Ni-Fe-P合金的晶化行为和结构.结果表明,镀态合金呈非晶结构, 367.6 ℃下热处理出现亚稳态Ni5P2(P3)和Fe-Ni(Im3m), 499.2 ℃下热处理进一步晶化为稳定的Ni3P(I-4)和FeNi3(Pm3m).采用磁性能实验和在w=3.5%氯化钠溶液浸泡实验以及阳极极化实验研究了热处理对镀层磁性能和耐腐蚀性的影响.结果表明,该镀层在镀态时几乎没有磁性,随着退火温度的升高,磁性能不断提高. 400 ℃以后,镀层的饱和磁化强度和矫顽力随着退火温度升高而急剧上升.浸泡实验和阳极极化实验结果均表明镀态镀层比经热处理后的镀层在w=3.5%氯化钠溶液中具有更好的耐腐蚀性,但是它们的阳极极化行为不同.  相似文献   

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