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1.
探讨了经济增长及金融发展与城乡收入差距之间互动影响,刻画了三者间的逻辑关系,并基于广西1990-2017年的统计数据,运用状态空间模型及卡尔曼滤波算法对三者间动态关系进行了实证分析.结果显示:经济增长对城乡收入差距呈现倒U型曲线形态,而金融发展则显示出具有不断缩小城乡收入差距的趋势.  相似文献   
2.
In China, Semen Cassiae has long been used to protect liver, brighten eyes, and relieve constipation. Prepared Semen Cassiae is produced from raw Semen Cassiae by processing, the two forms of Semen Cassiae have different clinical applications. Pathological state is an important factor affecting the efficacy of drugs, the pharmacokinetic behavior of drugs could be significantly changed when people or animal were under different pathological state. To clarify the effect of processing mechanism and pathological state for pharmacokinetic behavior, the pharmacokinetics of nine components of raw and prepared Semen Cassiae under normal and acute liver injury rats were examined. The results showed that the bimodal phenomenon appeared on the plasma concentration‐time profiles of obtusin, emodin, chrysophanol, aloe emodin and rhein. The Tmax of aurantio‐obtusin, obtusin, chrysoobtusin, emodin, chrysophanol, aloe emodin, physcion in normal groups administrated prepared Semen Cassiae were shorter than those administrated raw Semen Cassiae. For the AUC0–t, aurantio‐obtusin, obtusin, chrysoobtusin, chrysophanol, aloe emodin and physcione in model groups administrated prepared Semen Cassiae were significantly higher than other groups, unlike above components, rhein had poor absorption in model groups. The study would be useful for further studies on pharmacokinetics and clinical application of raw and prepared Semen Cassiae.  相似文献   
3.
Dan‐Huang‐Qu‐Yu capsule, a Chinese herbal medicine compound preparation, is widely used for chronic pelvic inflammatory disease. In this study, a rapid, selective, and sensitive microwave‐assisted extraction ultra‐high‐performance liquid chromatography‐Q Exactive quadrupole‐orbitrap high‐resolution mass spectrometry method was developed for analyzing its chemical compositions. A total of 85 compounds, including 22 flavonoids, 8 terpenoids, 5 quinones, 5 phthaleolactone, 23 organic acids, and 22 other compounds were identified from Dan‐Huang‐Qu‐Yu capsule. Among them, 35 major compounds were unambiguously detected by comparing them with reference standards and selected as quality control markers, which were simultaneously determined in Dan‐Huang‐Qu‐Yu capsule. The established method was successfully validated and applied for simultaneous determination of 35 bioactive compounds in Dan‐Huang‐Qu‐Yu capsule from ten sample batches. The quantitative data of the analytes were analyzed by principal component analysis for quality assessment of Dan‐Huang‐Qu‐Yu capsule. Six compounds (e.g., astragaloside IV, salvianolic acid B, ellagic acid, chlorogenic acid, N‐butylidenephthalide, and luteolin) were screened out and regarded as chemical markers for quality control of Dan‐Huang‐Qu‐Yu capsule. The established method has been proved to be a novel and useful tool for rapid research of Dan‐Huang‐Qu‐Yu capsule. This research will provide reference for the scientific research of traditional Chinese medicines.  相似文献   
4.
A novel analytical quality by design approach for developing a chromatographic fingerprint was established for analyzing complex traditional Chinese medicine, using a licorice standard decoction as an example. Considering the characteristics of integrity and ambiguity, the resolution of eight common peaks, total peak number, capacity factor distributions, and peak purity were selected as potential critical method attributes for assessing the quality of the chromatographic fingerprint. A central composite design was used to evaluate the relationship between critical method attributes and critical method parameters, including column temperature, wavelength, flow rate, formic‐acid concentration, and gradient parameters. A standard probability method was employed to calculate the design space of the fingerprint analysis parameters and evaluate the robustness of the methodology. The optimized high‐performance liquid chromatography fingerprint conditions were acetonitrile and 0.1% formic acid water gradient elution (0‐5 min, 5–19% A; 5–10 min, 19% A; 10–50 min, 19–42% A; 50–54 min, 42–100% A; 54–60 min, 100% A), column temperature 25±5°C, detection wavelength 265 nm. The design space of fingerprint analytical method based on the analytical quality by design approach not only met the requirements of the fingerprint analysis, but also improved the robustness and applicability of the fingerprint method.  相似文献   
5.
Tanreqing capsule (TRQC) is a formulation frequently used in traditional Chinese medicine to treat pyrexia, cough, expectoration and pharyngalgia. Since the pharmacological action of traditional Chinese medicines is closely related to their complex and diverse constituents, understanding the exact composition of TRQC is important to elucidate its clinical effectiveness and mechanism of action as well as to establish quality control methods and resolve safety issues. Herein, we employed high‐performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry for the simultaneous quantitation of 23 bioactive compounds in five batches of TRQC; the analytes could be categorized into five types: organic acids (seven compounds), flavonoids (10 compounds), iridoids (two compounds), phenylethanoid glycosides (two compounds) and bile acids (two compounds). The calibration curves for all analytes showed good linearity (r > 0.9953), and the inter‐ and intra‐day precisions did not exceed 4.94 and 4.97%, respectively. The recoveries varied from 90.47% to 109.80%; the corresponding relative standard deviations (RSDs) did not exceed 4.94%; and the repeatability (RSD < 4.72%) and stability (RSD < 4.88%) were also within acceptable limits. Thus, this study can be viewed as a fundamental reference for setting comprehensive TRQC quality standards.  相似文献   
6.
7.
In this study, a rapid and highly sensitive ultra high performance liquid chromatography with triple quadrupole mass spectrometry method with the mobile phase of acetonitrile and 0.1% aqueous formic acid was established and successfully applied to comparatively analyze main active components after their compatibility. Besides, the effects of Scutellariae Radix, Coptidis Rhizoma and combined extracts on type 2 diabetic rats induced by high‐fat diet along with low dose of streptozocin were investigated. Under the optimized chromatographic conditions, good separation of seven target components was achieved within 12 min. All calibration curves exhibited good linearity (R2 ≥ 0.999). The relative standard deviation of precision, repeatability and stability varied from 0.69 to 2.23, 0.98 to 2.56, and 0.92 to 2.57%, respectively. The recovery ranged from 91.11 to 105.35%. The contents of seven active components were notably reduced after compatibility; however, the hypoglycemic effect of combined extracts was stronger than single drug by decreasing the activities of fructose‐1,6‐bisphosphatase, glucose 6‐phosphatase, phosphoenolpyruvate carboxykinase and increasing the activities of glucokinase, phosphofructokinase, pyruvate kinase. Accordingly, the established analytical method was accurate and sensitive enough for quantitative evaluation of seven investigated compounds. Moreover, the combined extract had definite effects on type 2 diabetes through multiple components against multiple targets.  相似文献   
8.
Ligustrazine was the active ingredient of the traditional Chinese medicine Chuanxiong Rhizoma. However, the content of ligustrazine is very low. We proposed a hypothesis that ligustrazine was produced by the mutual effects between endophytic Bacillus subtilis and the Ligusticum chuanxiong Hort. This study aimed to explore whether the endophytic B. subtilis LB5 could make use of Chuanxiong Rhizoma fermentation matrix to produce ligustrazine and clarify the mechanisms of action preliminarily. Ultra high performance liquid chromatography with quadrupole time‐of‐flight mass spectrometry analysis showed the content of ligustrazine in Chuanxiong Rhizoma was below the detection limit (0.1 ng/mL), while B. subtilis LB5 produced ligustrazine at the yield of 1.0268 mg/mL in the Chuanxiong Rhizoma‐ammonium sulfate fermentation medium. In the fermented matrix, the reducing sugar had a significant reduction from 12.034 to 2.424 mg/mL, and rough protein content increased from 2.239 to 4.361 mg/mL. Acetoin, the biosynthetic precursor of ligustrazine, was generated in the Chuanxiong Rhizoma‐Ammonium sulfate (151.2 mg/mL) fermentation medium. This result showed that the endophytic bacteria B. subtilis LB5 metabolized Chuanxiong Rhizoma via secreted protein to consume the sugar in Chuanxiong Rhizoma to produce a considerable amount of ligustrazine. Collectively, our preliminary research suggested that ligustrazine was the interaction product of endophyte, but not the secondary metabolite of Chuanxiong Rhizoma itself.  相似文献   
9.
Forsythiaside A is the major component of Forsythia suspensa. This study investigated the degradation mechanism of forsythiaside A. Eight degraded components including forsythiaside I, forsythiaside H, forsythiaside E, caffeic acid, suspensaside A, β‐hydroxy forsythiaside I, β‐hydroxy forsythiaside H, and β‐hydroxy forsythiaside A were identified by using ultra‐high performance liquid chromatography quadrupole time‐of‐flight mass spectrometry. Then, the quantitative analysis of multi‐components by a single‐marker was performed with ultra‐high performance liquid chromatography to simultaneously determine forsythiaside A, forsythiaside H, and forsythiaside I in Forsythia suspensa preparations. The result showed good linear relationships within 2.871–287.1, 0.231–23.1, and 0.983–98.3 μg/mL (r > 0.9998), with average recoveries of 97.7, 95.7, and 95.8% and relative standard deviations of 1.4, 2.4, and 1.8%, respectively. Using forsythiaside A as an internal reference, the relative retention values of forsythiaside H and forsythiaside I to forsythiaside A were calculated to be 0.89 and 0.61, respectively, and the relative correction factors were 0.816 and 0.799, respectively. The method for quantitative analysis of multi‐components by a single‐marker was applied to evaluate the overall quality of forsythia preparations. There was no significant difference in the measurement results of the method developed and the method of external standard.  相似文献   
10.
To explore the global mechanism of Ermiaowan on hyperuricemia regulation, the holistic function of Ermiaowan for hyperuricemia in rats was firstly assessed by the urinary metabonomics method which was based on ultra‐high performance liquid chromatography with electrospray ionization quadrupole time‐of‐flight mass spectrometry. The urinary targeted metabonomics approach combined with the serum biochemical analysis and histological assay was conducted to verify the research result. As a result, the significant differences in metabolic profiles were observed from Ermiaowan‐treated group, model group, and healthy control group by using multivariate statistical approaches. Twenty therapeutic related metabolites were identified in response to the therapeutic effects of Ermiaowan, which were mainly associated with purine metabolism, pyrimidine metabolism, tryptophan metabolism, tricarboxylic acid cycle, and tyrosine metabolism. In addition, the urinary targeted metabonomics study showed that Ermiaowan can better restore the disturbed pathways than Phellodendri cortex and Atractylodis rhizome. The biochemical assay and histopathological assay confirmed that Ermiaowan could significantly reduce uric acid and fibrosis areas of kidney. These results provided new insights into the mechanism of Ermiaowan on hyperuricemia.  相似文献   
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