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51.
采用亚急性试验,探讨对二氯苯(P—DCB)对小鼠组织中Zn、Cu、Fe的影响。选用36只小鼠,雌雄各半,随机分成3组,每组12只,分别给予P—DCBO(对照组)、450、900mg·kg^-1,每天灌胃染毒1次,连续7d,染毒结束后24h处死动物并称体质量、肝、肾质量,计算脏器系数。用火焰原子吸收法测定肝脏、血液和肾脏中Zn、Cu、Fe含量。与对照组相比,各染毒组体质量无明显变化。各组肝体系数无差异,但染毒组肾体系数明显高于对照组(P〈O.05)。900mg·kg^-1组肝脏中Zn含量及w(Zn)/w(Cu)值较450mg·kg^-1组有明显升高。与对照组相比,各染毒组血液中Zn含量呈现下降趋势,900nag·kg^-1组较对照组明显下降(P〈0.05)。900mg·kg^-1组肾脏中Cu质量分数明显低于450mg·kg^-1组,Fe质量分数则较对照组及450mg·kg^-1组均有降低,P—DCB可影响小鼠组织中元素Zn、Cu、Fe的含量及不同器官的再分布,提示微量元素失衡可能是P—DCB毒作用的重要机制。 相似文献
52.
建立了一种基于高效液相色谱-超高分辨质谱技术的肾脏代谢组学分析方法。肾脏组织于液氮中研磨成粉后,采用甲基叔丁基醚/甲醇/水溶剂体系进行提取,分别得到强极性部分(下层)和弱极性部分(上层)提取物,依次采用HILIC亲水色谱柱和反相C18色谱柱进行梯度洗脱分离后,进行高分辨质谱分析。采用电喷雾离子源(ESI),正、负离子模式检测,扫描方式为全扫描,扫描范围为100~1000 Da,质量分辨率为120000。结果表明,该方法灵敏度高,专属性强,稳定性良好,可同时获取肾脏组织中的强极性和弱极性代谢物信息,可为肾脏疾病和药物肾毒性生物标志物的发现提供一种新的方法。 相似文献
53.
Anxiety is a chronic severe psychiatric disorder. Crocins are among the various bioactive components of the plant Crocus sativus L. (Iridaceae) and their implication in anxiety is well-documented. However, which is the mechanism of action underlying the anti-anxiety effects of crocins remains unknown. In this context, it has been suggested that these beneficial effects might be ascribed to the agonistic properties of these bioactive ingredients of saffron on the GABA type A receptor. The current experimentation was undertaken to clarify this issue in the rat. For this research project, the light/dark and the open field tests were used. A single injection of crocins (50 mg/kg, i.p., 60 min before testing) induces an anti-anxiety-like effect revealed either in the light-dark or open field tests. Acute administration of the GABAA-benzodiazepine receptor antagonist flumazenil (10 mg/kg, i.p., 30 min before testing) abolished the above mentioned anxiolytic effects of crocins. The current findings suggest a functional interaction between crocins and the GABAA receptor allosteric modulator flumazenil on anxiety. 相似文献
54.
本文主要探究SOFA评分联合超声对脓毒症合并急性肾损伤(AKI)患者的预后价值。选取2017年1月~2019年1月本院脓毒症合并AKI患者50例作为观察组,并分为AKI 1、2、3期,将同期入院的50例脓毒症患者作为对照组,两组患者均采用SOFA评分联合超声进行预后评估。结果发现,观察组PDU评分低于对照组(P<0.05),RI值、SOFA评分高于对照组(P<0.05);不同分期的3组间的PDU评分、SOFA评分不同,随着AKI分期的增加,PDU评分降低、SOFA评分增加(P<0.05),但3组间的RI值并无不同(P>0.05);50例脓毒症合并AKI患者发生院内死亡率为44.00%。经单因素分析发现,年龄、机械通气时间、ICU住院时间、AKI分期、脓毒症休克、SOFA评分、PDU评分为影响患者预后不佳的因素(P<0.05);AKI3期、发生脓毒性休克、SOFA评分、PDU评分是脓毒症合并AKI患者预后不佳的独立因素(P<0.05),ROC曲线下面积(AUC)越大,对预后的预测效能越好,当AUC>70.00%时具有临床价值。两者联合显著高于单独应用SOFA评分(AUC=74.28%)或PDU评分(P<0.001)。上述结果说明,脓毒症合并AKI患者采用SOFA评分联合超声用于评估患者的预后,优于单独采用SOFA评分或超声,两者联合的预测价值更大。 相似文献
55.
Simultaneous determination of piperaquine and its N‐oxidated metabolite in rat plasma using LC‐MS/MS
《Biomedical chromatography : BMC》2017,31(10)
A sensitive and efficient liquid chromatography tandem mass spectrometry method was developed and validated for the simultaneous determination of piperaquine (PQ) and its N ‐oxidated metabolite (PQ‐M) in plasma. A simple protein precipitation procedure was used for sample preparation. Adequate chromatographic retention was achieved on a C18 column under gradient elution with acetonitrile and 2 mm aqueous ammonium acetate containing 0.15% formic acid and 0.05% trifluoroacetic acid. A triple‐quadrupole mass spectrometer equipped with an electrospray source was set up in the positive ion mode and multiple reaction monitoring mode. The method was linear in the range of 2.0–400.0 ng/mL for PQ and 1.0–50.0 ng/mL for PQ‐M with suitable accuracy, precision and extraction recovery. The lower limits of detection (LLOD) were established at 0.4 and 0.2 ng/mL for PQ and PQ‐M, respectively, using 40 μL of plasma sample. The matrix effect was negligible under the current conditions. No effect was found for co‐administrated artemisinin drugs or hemolysis on the quantification of PQ and PQ‐M. Stability testing showed that two analytes remained stable under all relevant analytical conditions. The validated method was successfully applied to a pharmacokinetic study performed in rats after a single oral administration of PQ (60 mg/kg). 相似文献
56.
《Biomedical chromatography : BMC》2017,31(9)
We developed a serum metabolomic method by gas chromatography–mass spectrometry (GC–MS) to evaluate the effect of alprazolam in rats. The GC–MS with HP‐5MS (0.25 μm × 30 m × 0.25 mm) mass was conducted in electron impact ionization (EI) mode with electron energy of 70 eV, and full‐scan mode with m /z 50–550. The rats were randomly divided to four groups, three alprazolam‐treated groups and a control group. The alprazolam‐treated rats were given 5, 10 or 20 mg/kg (low, medium, high) of alprazolam by intragastric administration each day for 14 days. The serum samples were corrected on the seventh and fourteenth days for metabolomic study. The blood was collected for biochemical tests. Then liver and brain were rapidly isolated and immersed for pathological study. Compared with the control group, on the seventh and fourteen days, the levels of d ‐glucose, 9,12‐octadecadienoic acid, butanoic acid, l ‐proline, d ‐mannose and malic acid had changed, indicating that alprazolam induced energy metabolism, fatty acid metabolism and amino acid metabolism perturbations in rats. There was no significant difference for alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, urea and uric acid between controls and alprazolam groups. According to the pathological results, alprazolam is not hepatotoxic. Metabolomics could distinguish different alprazolam doses in rats. 相似文献
57.
《Biomedical chromatography : BMC》2017,31(8)
The determination of amino acids with actions like neurotransmitters or modulators has been increasingly important for diagnosis in many neuropsychiatric diseases. A rapid and simple high‐performance liquid chromatography with fluorescence detection method was developed for simultaneous determination of seven amino acids: aspartate (Asp), glutamate (Glu), serine (Ser), glutamine (Gln), glycine (Gly), taurine (Tau) and γ‐aminobutyric` acid (GABA). Homoserine was used as an internal standard. The analysis was performed on a BDS column with methanol and 50 mm sodium acetate solution (pH 6.5) using a simple gradient elution. Several parameters of the developed method were validated including linearity, accuracy, precision, extraction recovery and stability, which were within the acceptable range. The method was successfully applied to determination of real samples: hippocampus and cortex in depressed rats exposed to chronically unpredictable stress in order to study if there existed differences in the seven amino acids levels between depressed rats and control. The results showed that Asp, Gly, Tau and GABA significantly decreased with increasing Gln in the hippocampus of depressed rats, compared with that of the control group, among which obviously lower level of Asp and higher level of Gln in cortex were observed. The analytical method and the results could be useful for clinical diagnosis and further insight into pathophysiological mechanism of depression. 相似文献
58.
Simultaneous determination of cucurbitacin IIa and cucurbitacin IIb of Hemsleya amabilis by HPLC–MS/MS and their pharmacokinetic study in normal and indomethacin‐induced rats 下载免费PDF全文
Shougang Wang Xiaohui Guan Xiuhong Zhong Zhiping Yang Weili Huang Baoyang Jia Tao Cui 《Biomedical chromatography : BMC》2016,30(10):1632-1640
A selective and sensitive HPLC–MS/MS method was developed for the simultaneous determination of cucurbitacin IIa (cuIIa) and cucurbitacin IIb (cuIIb), the major bioactive cucurbitacins of Hemsleya amabilis, in rat plasma using euphadienol as internal standard (IS). After liquid–liquid extraction with dichloromethane, separation was achieved on a Syncronis HPLC C18 column (150 mm × 4.6 mm, 5 μm) using an isocratic mobile phase system consisting of acetonitrile–water (85:15, v/v) at a flow rate of 0.6 mL/min with a split ratio of 1:2. Detection was performed on a TSQ Quantum Ultra mass spectrometer equipped with an positive‐ion electrospray ionization source. The lower limits of quantification (LLOQs) were 0.25 and 0.15 ng/mL for cuIIa and cuIIb, respectively. The intra‐ and inter‐day precision was <11.5% for the LLOQs and each quality control level of the analytes, and accuracy was between ?9.1 and 7.6%. The extraction recoveries of the analytes and IS from rat plasma were all >87.1%. The method was fully validated and applied to compare the pharmacokinetic profiles of the two cucurbitacins in rat plasma after oral administration of H. amabilis extract between normal and indomethacin‐induced rats. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
59.
Maura Pellei Carlo Santini Giancarlo Gioia Lobbia Franco Cantalamessa Cinzia Nasuti Mariacristina Di Prinzio Rosita Gabbianelli Giancarlo Falcioni 《应用有机金属化学》2005,19(5):583-589
New organotin(IV) derivatives containing the anionic ligands bis(3,5‐dimethylpyrazol‐1‐yl)dithioacetate [LCS2]− and bis(3,5‐dimethylpyrazol‐1‐yl)acetate [LCO2]− have been synthesized from reaction between (CH3)2SnCl2 and lithium salts of the ligands. Mononuclear complexes of the type {[LCX2](CH3)2SnCl} (X = S or O) have been obtained and fully characterized by elemental analyses and FT‐IR in the solid state and by NMR (1H, 13C and 119Sn) spectroscopy, conductivity measurements and electrospray ionization mass spectrometry in solution. The acute toxicity of new organotin(IV) derivatives on rat was studied, comparing their effect with those of dimethyltin chloride (CH3)2SnCl2. The comparison of LD50 of organotin(IV) complexes and (CH3)2SnCl2 administered intraperitoneally, as a single dose, evaluated in vivo on rats, showed that toxicity decreases as follows: (CH3)2SnCl2 > LCO2 > LCS2. The effect of these organotin(IV) complexes on DNA was evaluated in vitro and in vivo on rats treated with different doses of these compounds (1/20 LD50 and 1/100 LD50). The lymphocyte DNA status was assessed by the comet assay, a rapid and sensitive single‐cell electrophoresis technique, used to detect primary DNA damage in individual cells. After 36 h from the start of treatment the two new organotin(IV) derivatives induced a significant rise in comet assay parameters, indicating an increasing presence of damaged DNA. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
60.
Xianqin Wang Jiayin Zhu Renai Xu Xuezhi Yang Haiya Wu Dan Lin Faqing Ye Lufeng Hu 《Biomedical chromatography : BMC》2010,24(10):1108-1112
A sensitive and selective liquid chromatography–tandem mass spectrometry method for the determination of piracetam in rat plasma was developed and validated over the concentration range of 0.1–20 µg/mL. After addition of oxiracetam as internal standard, a simplified protein precipitation with trichloroacetic acid (5%) was employed for the sample preparation. Chromatographic separation was performed by a Zorbax SB‐Aq column (150 × 2.1 mm, 3.5 µm). The mobile phase was acetonitrile–1% formic acid in water (10:90 v/v) delivered at a flow rate of 0.3 mL/min. The MS data acquisition was accomplished in multiple reaction monitoring mode with a positive electrospray ionization interface. The lower limit of quantification was 0.1 µg/mL. For inter‐day and intra‐day tests, the precision (RSD) for the entire validation was less than 9%, and the accuracy was within the 94.6–103.2% range. The developed method was successfully applied to pharmacokinetic studies of piracetam in rats following single oral administration dose of 50 mg/kg. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献