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121.
A high-performance liquid chromatography-tandem mass spectrometry method was established for the simultaneous determination of mycophenolic acid, mycophenolate mofetil, tacrolimus, rapamycin, everolimus and pimecrolimus in human whole blood by optimizing the QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) preparation method. Whole blood was extracted into ethyl acetate, salted out with anhydrous magnesium sulfate, and purified with ethylenediamine-N-propyl silane adsorbent. The supernatant was evaporated under nitrogen until dry and finally reconstituted in methanol. Chromatographic separation was performed on an Agilent Poroshell 120 EC-C18 column in methanol (mobile phase A)-water (optimized for 0.1% acetic acid and 10 mM ammonium acetate, mobile phase B) at a 0.3 mL·min−1 flow rate. Electrospray ionization and positive ion multiple reaction monitoring were used for detection. The time for of analysis was 13 min. The calibration curves range of tacrolimus, rapamycin, everolimus and pimecrolimus were in the range of 1–100 ng·mL−1, mycophenolate mofetil in the range of 0.1–10 ng·mL−1 and mycophenolic acid at 10–1000 ng·mL−1. All correlation coefficients were >0.993. The coefficients of variation (CV, %) for inter-day and intra-day precision were less than 10%, while the spiked recoveries were in the range of 92.1% to 116%. Our method was rapid, sensitive, specific, and reproducible for the simultaneous determination of six immunosuppressants in human whole blood. Importantly, our approach can be used to monitor drug concentrations in the blood to facilitate disease treatment. 相似文献
122.
桑蚕种良卵率是蚕种质量检验的重要指标,控制样本间卵粒数的偏差是保证良卵率准确性的关键。通过对桑蚕卵粒重的调查分析,得出其分布服从正态分布。若从一批蚕种中抽取1g卵作为样本,则来自同一总体的2个样本的卵粒数之差不超过16粒,其置信概率为95%;当置信概率取99%时,两个样本的卵粒数之差不超过21粒。文章为蚕业生产提供了一种实用的克卵粒数偏差控制方法。 相似文献
124.
125.
薄层色谱-紫外可见分光光度法测定食品中的苏丹红Ⅰ号 总被引:1,自引:0,他引:1
建立了测定食品中苏丹红Ⅰ号新方法:薄层色谱-紫外可见分光光度法.方法的线性回归方程为:A=0.00583 0.15105ρ,在0.50~10.0 μg/mL之间苏丹红Ⅰ号的浓度与吸光度之间呈线性关系,相关系数R=0.9992,检出限为0.05 μg/mL.测定结果与国家标准HPLC法对照,令人满意.可用于食品中苏丹红Ⅰ号的测定. 相似文献
126.
127.
Bingchao Qi Liqiang Song Lang Hu Dong Guo Gaotong Ren Tingwei Peng Mingchuan Liu Yexian Fang Chunyu Li Mingming Zhang Yan Li 《Experimental & molecular medicine》2022,54(7):946
Myocardial infarction (MI) is the leading cause of premature death among adults. Cardiomyocyte death and dysfunction of the remaining viable cardiomyocytes are the main pathological factors of heart failure after MI. Mitochondrial complexes are emerging as critical mediators for the regulation of cardiomyocyte function. However, the precise roles of mitochondrial complex subunits in heart failure after MI remain unclear. Here, we show that NADH:ubiquinone oxidoreductase core subunit S1 (Ndufs1) expression is decreased in the hearts of heart failure patients and mice with myocardial infarction. Furthermore, we found that cardiac-specific Ndufs1 overexpression alleviates cardiac dysfunction and myocardial fibrosis in the healing phase of MI. Our results demonstrated that Ndufs1 overexpression alleviates MI/hypoxia-induced ROS production and ROS-related apoptosis. Moreover, upregulation of Ndufs1 expression improved the reduced activity of complex I and impaired mitochondrial respiratory function caused by MI/hypoxia. Given that mitochondrial function and cardiomyocyte apoptosis are closely related to heart failure after MI, the results of this study suggest that targeting Ndufs1 may be a potential therapeutic strategy to improve cardiac function in patients with heart failure.Subject terms: Heart failure, Myocardial infarction, Myocardial infarction 相似文献
128.
Noether-Mei Symmetry of Mechanical System in Phase Space 总被引:1,自引:0,他引:1
In this paper, a new kind of symmetry and its conserved
quantities of a mechanical system in phase space are studied.
The definition of this new symmetry, i.e., a Noether-Mei symmetry,
is presented, and the criterion of this symmetry is also given.
The Noether conserved quantity and the Mei conserved quantity
deduced from the Noether-Mei symmetry of the system are obtained.
Finally, two examples are given to illustrate the application of the results. 相似文献
129.
In Phys. Lett. A 313 (2003) 343 we have found that the
self-reciprocal Hankel transformation (HT) is embodied in quantum
mechanics by a transform between two entangled state representations
of continuum variables. In this
work we study Hankel transforms and properties of Bessel function via
entangled state representations' transformation in quantum mechanics. 相似文献
130.
In this paper, a quantum secure direct communication protocol using ensembles with the same density matrix is proposed. The two communication parties can realize the message transmission using this method through a quantum channel, each bit of information can be transmitted using an ensemble and read out through global measurement.The eavesdropping behavior can be detected through the channel diagnoses. 相似文献