首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 920 毫秒
1.
利用高分辨魔角旋转核磁共振技术(HR-MAS NMR)以及主成分分析法(PCA)对大鼠肝脏组织纤维化病变前后以及不同程度病变的代谢产物变化进行了研究. 结果表明, 纤维化病变使得肝脏脂肪含量增加; 葡萄糖、糖原、牛磺酸以及肌醇的含量相对减小. 相对磷酸胆碱(PC)而言, 胆碱(Cho)及甘油磷酸胆碱(GPC)降低. 随着正常至纤维化病变程度的加深, 脂肪含量有一个先显著上升, 再缓慢下降的趋势; 而不同程度纤维化病变阶段之间其它代谢产物的变化不明显. 主成分分析证实了上述的结果, 正常与纤维化病变样本中代谢产物的组成存在较大的差异性, 可被明显分为两组; 而各纤维化病变阶段之间的差异不明显.  相似文献   

2.
去卵巢大鼠骨元素代谢紊乱机制研究   总被引:1,自引:0,他引:1  
测定了去卵巢大鼠骨元素含量和血清相关激素和细胞因子含量,分析了去卵巢大鼠骨元素代谢紊乱的机制。将健康4月龄SD大鼠18只随机分成3组:正常对照组,假去卵巢大鼠组和去卵巢大鼠组。结果表明,去卵巢大鼠骨Ca、Mg、S、Mn、Zn等含量显著降低,P含量显著升高,血清E2、P、CT、GH等含量显著降低,IL-6、FSH、LH等含量显著升高。提示去卵巢大鼠骨元素代谢紊乱是雌激素水平下降与其他因素共同作用的结果。  相似文献   

3.
甲亢患者血清和尿液的核磁共振代谢组学研究   总被引:2,自引:1,他引:1  
应用基于核磁共振(NMR)的代谢组学方法, 研究甲状腺功能亢进(简称甲亢)患者和健康人群的血清和尿液, 分析甲亢疾病的特征代谢物. 实验收集33个甲亢患者和17个健康志愿者的血清样品以及53个甲亢患者和58个健康志愿者的尿液样品, 采用多元统计分析方法研究甲亢组和对照组血清和尿液中的内源性代谢差异. 结果表明, 甲亢组血清中的胆碱、葡萄糖和三甲胺等物质的含量升高, 而VLDL, LDL和胆固醇等脂质以及乳酸、糖蛋白和丙氨酸等代谢物的含量下降; 甲亢组尿液中的葡萄糖、柠檬酸、牛磺酸以及肌氨酸等代谢物的含量升高, 而马尿酸、TMAO、甲酸和琥珀酸等代谢物的含量下降. 结果表明, 甲亢病不仅影响了糖类、脂类和蛋白质三大物质的代谢, 还对能量代谢、肝肠循环和肠道微生物等多个生理系统产生显著影响, 并且可能造成肝脏及肾脏等器官的损伤.  相似文献   

4.
采用核磁共振波谱技术测试不同性别大鼠尿液代谢物,分析性别因素对大鼠尿液代谢成分的影响.大鼠尿液核磁共振氢谱(1HNMR谱)结果采用主成分分析(principal component analysis,PCA)和正交偏最小二乘判别分析(orthogonal to partial least squares discriminant analysis,OPLS-DA)方法分析,得到不同性别大鼠尿液中的差异性代谢物.PCA分析结果显示2组尿液代谢成分有明显的差异,进一步进行OPLS-DA分析可以判别出2组尿液中具有差异性的代谢物.结果显示,雌性大鼠尿液中的丙氨酸、缬氨酸、鸟氨酸等氨基酸类以及乙酸、硫胺、氨基马尿酸、苯乙胺、氧氨嘧啶等代谢物含量高于雄性大鼠,差异有统计学意义(p〈0.05).雄性大鼠尿液中的甲胺、二甲胺、三甲胺、肌酸酐、尿囊素、延胡索酸、甲酸等代谢物则明显高于雌性大鼠,差异有统计学意义(p〈0.05).性别因素对大鼠尿液中的代谢成分有一定的影响.  相似文献   

5.
复方丹参滴丸抗急性心肌梗死代谢组学研究   总被引:2,自引:0,他引:2  
采用左冠状动脉前降支结扎的方法,建立SD大鼠急性心肌梗死(Acute myocardial infarction, AMI)模型,使用超高效液相色谱-串联四极杆/飞行时间质谱(UPLC-QTOF/MS)代谢组学研究平台对大鼠血浆样本进行代谢轮廓分析,研究复方丹参滴丸对AMI大鼠心肌保护作用机制.经主成分分析和偏最小二乘法分析,筛选并鉴定出22种与AMI相关的差异代谢物,其中的8种能够被复方丹参滴丸显著调节,分别是硫酸对甲苯、马尿酸、雌马酚葡萄糖苷酸、溶血磷脂胆碱(16∶0)、胆酸、油酸酰胺、棕榈酰胺和鞘脂(d18∶1/16∶0).研究结果表明, 复方丹参滴丸可能是通过调节苯丙氨酸代谢、甘油磷脂代谢、脂肪酸代谢、胆汁酸代谢及鞘脂代谢通路,发挥抗AMI大鼠心肌损伤的作用.  相似文献   

6.
卵巢早衰是妇科领域的常见病,中医认为卵巢早衰与肝肾的正常与否息息相关,通过药食两用物质对肝脏代谢的调理是治疗卵巢早衰的一种重要手段。该研究基于超高效液相色谱-三重四极杆质谱(UHPLC-MS/MS)建立的广泛靶向代谢组学技术,探讨破壁松花粉对环磷酰胺诱导的卵巢早衰模型大鼠肝脏代谢的影响,旨在通过测定对照组、模型组、雌激素阳性对照组及施以不同剂量的松花粉干预组的SD大鼠肝脏组织中代谢物的含量变化,结合主成分分析(PCA)、正交偏最小二乘判别分析(OPLS-DA)等多元统计方法揭示松花粉干预卵巢早衰大鼠肝脏代谢的作用机制。通过正、负离子模式共检测出687种肝脏代谢物,PCA与OPLS-DA显示环磷酰胺诱导的模型组能够与对照组、阳性对照组、松花粉干预组等组别之间的代谢物较好的分离。通过单变量分析中的t检验(p<0.05)、变异倍数(FC>2或<0.5)与多变量分析中变量投影重要性(VIP值)>1相结合对差异代谢物进行筛选。与对照组相比,模型组SD大鼠肝脏中的32个生物标志物含量显著升高,28个生物标志物含量显著降低,主要涉及α-亚麻酸代谢、维生素B6代谢、嘌呤代谢、赖...  相似文献   

7.
采用超高效液相色谱-飞行时间质谱联用技术(UPLC-Q/TOF MS)对恩施土家族苗族自治州60例健康志愿者(对照组)和65例痛风患者(痛风组)的血清样本建立代谢图谱,基于主成分分析及正交偏最小二乘判别分析对所得数据进行模式识别,并结合变量权重投影分析及火山图筛选出痛风患者的血清代谢标志物。通过数据分析和数据库检索,共筛选出63种差异代谢物,其中27种代谢物显著上调(P <0.05),36种代谢物显著下调(P <0.05),主要包括甘油磷脂类、氨基酸类及胆碱等成分。首先,对以上差异代谢物进行受试者工作特征曲线(ROC)分析,其中曲线下面积(AUC)大于0.8的14种代谢物是诊断效能较好的代谢物;然后对筛选的63种差异代谢物进行代谢通路富集分析,以Impact> 0.1且P <0.05为标准,得到影响最大的代谢通路主要有甘油磷脂代谢、醚性脂质代谢、亚油酸代谢、半胱氨酸和蛋氨酸代谢、花生四烯酸代谢及戊糖和葡萄醛酸的互相转化等。综上,痛风患者和健康对照人群的血清代谢水平有明显差异,差异代谢物的鉴定为痛风的发病机制和早期筛查提供了实验依据。  相似文献   

8.
运用代谢组学方法研究了Wistar大鼠灌胃给药砒霜2和10 mg/kg剂量血清代谢的变化。通过核磁共振技术检测大鼠血清的代谢指纹图谱,然后利用主成分分析法分析空白组和砒霜给药组的代谢物差异,研究不同剂量砒霜在大鼠体内的急性生物效应。结果表明,砒霜对大鼠的急性靶向器官是肝脏,随着剂量增大,毒性增强;低剂量给药导致氧化应激,高剂量给药诱导细胞凋亡;低和高剂量给药均出现糖、氨基酸及脂质代谢紊乱,且能量代谢异常。  相似文献   

9.
尹春园  孙明谦  金龙  林力  苗兰  刘建勋 《色谱》2020,38(2):206-211
采用异丙肾上腺素诱导心肌缺血大鼠模型,使用液相色谱-质谱法检测血清和心肌中的内源性成分,应用软件对已鉴定的40余种目标成分进行靶向提取,用主成分分析(PCA)、有监督偏最小二乘法判别分析(PLS-DA)对代谢组学数据进行多维度统计分析,筛选潜在生物标志物。与对照组相比,在心肌缺血模型组大鼠血清、组织中检测出18个差异代谢物,涉及精氨酸和脯氨酸代谢、甘氨酸、丝氨酸和苏氨酸代谢、谷氨酰胺和谷氨酸代谢、牛磺酸和亚牛磺酸代谢等多条代谢通路。代谢产物可作为心肌缺血研究中的重要标志物,该研究结果有助于揭示心肌缺血的发病机制,可为临床疾病诊断提供思路。  相似文献   

10.
通过测定骨元素含量和血清相关激素及白细胞介素-6水平,探讨了利骨素对去卵巢大鼠骨元素代谢的影响及其机制。将健康4月龄雌性SD大鼠24只随机分成3组:A组,假去卵巢组;B组,去卵巢组;C组,去卵巢+利骨素组。结果表明,去卵巢大鼠骨Ca、Mg、S、Mn、Zn等含量显著降低,P含量显著增加;应用利骨素可使去卵巢大鼠降低的骨Ca、Mg、S、Mn、Zn等含量显著回升,P含量显著回降。血清相关激素:去卵巢组较假去卵巢组大鼠,血清雌二醇(E2)、孕酮(P)、促甲状腺激素(TSH)、甲状腺素(T4)、降钙素(CT)、皮质醇(Cortisol)、生长素(GH)等含量降低,卵泡刺激素(FSH)、黄体生成素(LH)、白细胞介素-6(IL-6)等含量升高;去卵巢+利骨素组较去卵巢组,血清P,GH,Cortisol,TSH,T4等含量回升,LH含量回降。提示利骨素改变去卵巢大鼠体内相关激素水平是其纠正去卵巢大鼠骨元素代谢紊乱作用的重要机制。  相似文献   

11.
The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.  相似文献   

12.

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

  相似文献   

13.
非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。  相似文献   

14.
Two vanilloids, (5E)-8-(4-hydroxy-3-methoxyphenyl)oct-5-en-4-one (1) and 4-[3-hydroxydecyl]-2-methoxyphenol (2), isolated from the dried seeds of Grains of Paradise (Aframomum melegueta), were synthesized; the latter compound was made as the S-enantiomer and the material derived from the seeds was found to be a 1:1.7 mixture of the R and S isomers. The synthetic route used should allow the preparation of analogs having extended alkyl chains and consequently different lipophilicity, and 3, a homolog of 2, was also prepared.  相似文献   

15.
针对恶臭测试的环境影响问题,提出了解决的实例方案,并对方案的要点及优缺点进行讨论,此方案在实际操作中具有较好的效果。  相似文献   

16.
In this review, the research of the author in the field of colloidal systems is summarized. The factors influencing colloidal stability are systematized and analyzed. Examples are presented to illustrate the practical utilization of the theory of stability of colloids and thin films.This review was prepared on the basis of the works of the author, which were awarded the State Premium for 1991 in the field of science and technology, chemistry section.Institute of Physical Chemistry, Russian Academy of Sciences, 117915 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1708–1717, August, 1992.  相似文献   

17.
Main hydration products of two cement pastes, i.e. CSH-gel, portlandite (P) (and specific surface S) were studied by static heating, and by SEM, TEM and XRD, as a function of cement strength (C-33 and C-43) hydration time (th) and subsequent hydration in water vapour.Total change in mass on hydration and air drying, Mo, increased with strength of cement paste and with hydration time. Content of water escaping at 110 to 220°C, defined as water bound with low energy, mainly interlayer and hydrate water, was independent on cement strength but its content increased with (th). Content of chemically bound (zeolitic) water in CSH-gel, escaping at 220-400°C, was slightly dependent on strength and increased with (th). It was possibly derived from the dehydroxylation of CSH-gel and AFm phase. Portlandite water, escaping at 400-500°C, was independent on cement strength and was higher on longer hydration. Large P crystals were formed in the weaker cement paste C-33. Smaller crystals were formed in C-43 but they increased with (th). Carbonate formated on contact with air (calcite, vaterite and aragonite), decomposed in cement at 600-700oC. It was high in pastes C-33(1 month) and C-43(1 month), i.e. 5.7 and 3.3%, respectively; it was less than 1% after 6 hydration months (low sensitivity to carbonation) in agreement with the XRD study showing carbonates in the air dry paste (1month), and its absence on prolonged hydration (6 months) and on acetone treatment. Water vapour treatment of (6 months) pastes or wetting-drying increased this sensitivity.Nanosized P-crystals, detected by TEM, could contribute to the cement strength; carbonate was observed on the rims of gel clusters.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   

18.
袁丽秋 《化学教育》2006,27(5):8-10
面对日益枯竭的能源危机,氢能是一种洁净、最有前景的替代能源。目前在各种制氢的方法中光催化分解水制氢的研究最多,光解水过程中催化剂最关键,本文对利用太阳能光解水的途径、提高光催化反应效率以及光催化剂的开发研究进行了综述。  相似文献   

19.
20.
黄酮化合物的合成研究进展   总被引:2,自引:0,他引:2  
黄酮化合物是一类具有多种生物活性的天然产物,其经典的合成方法主要为查耳酮路线和β-丙二酮路线.近年来出现了许多新技术、新方法.本文介绍了2'-羟基查尔酮的氧化关环法、黄烷酮氧化法、改进的Baker-Venkataraman法及其他合成黄酮化合物的方法.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号