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1.
Simultaneous Determination of Six Compounds in Rat Plasma by Ultra‑Performance Liquid Chromatography with Tandem Mass Spectrometry: Application in the Pharmacokinetic Study of Qing Gan‑Shu Yu‑Fang 下载免费PDF全文
Hai Jiang A‑Jiao Hou Yan‑Yan Zhang Wen‑Jing Man Liu Yang Yong‑Hai Meng Xin‑Yue Guo Song Wang Jia‑Xu Zhang Bing‑You Yang Qiu‑Hong Wang Kelvin Chan Hai‑Xue Kuang 《World Journal of Traditional Chinese Medicine》2019,(4)
A rapid and high selective ultra?performance liquid chromatography (UPLC) with tandem mass spectrometry method for simultaneous
determination of six compounds including albiflorin, paeoniflorin, picroside I, picroside II, saikosaponin A, and saikosaponin D in rat plasma
was developed and validated using butyl p-hydroxybenzoate as an internal standard. One-step direct protein precipitation with acetonitrile was
used to extract the compounds from the rat plasma samples. Chromatographic separation was achieved using an ACQUITY UPLC BEH C18
column (100 mm × 2.1 mm, 1.7 µm) at a flow rate of 0.4 mL/min, using gradient mode containing 0.1% formic acid in water and acetonitrile
were used as the Mobile phase A and B. Electrospray ionization in negative ion mode and multiple reaction monitoring were used to identify
and quantify active components. Calibration curves showed good linearity (R2 > 0.9908) over a wide concentration range for all compounds.
The intra- and interday precision (relative standard deviation) ranged 2.4%–7.0% and 2.6%–8.0%, respectively. The accuracy (relative error)
was from ?13.0% to 13.2% at all quality control levels. The recovery ranged from 81.1% to 92.5%. The validated method was successfully
applied to pharmacokinetic study in rats after oral administration of Qing Gan?Shu Yu?Fang. The results show that one can draw a conclusion
that these six active ingredients can be quickly absorbed and play a pharmacodynamic role rapidly in vivo. 相似文献
2.
南极心理学研究的现状与展望 总被引:2,自引:0,他引:2
在过去30多年内,南极条约的许多成员国,诸如美国、澳大利亚、新西兰、法国、英国等国,已作了许多有关南极工作人员的人体生物,医学和心理学的研究,涉及问题广泛。仅与心理学有关的就包括:体温节律,温度应激,睡眠和昼夜节律。适应心理学方面的研究包括对被试者完成指定的操作的评价,心理调整及其在人员选拔中的应用,压抑和焦虑等心理紊乱因素,动机,态度和人格改变;认知操作,领导和越冬人员间的人际关系以及其它各种心 相似文献
3.
Sun Ren-yu孙仁宇 Yan Yi-zhao严仪昭 Zhang Hong张宏and Li Chang-cheng李长城Institute cf Basic Metiical Sciences Chinee Academy of Medical Sciences Beijing 《中华医学杂志(英文版)》1989,102(1):1-6
Acute pulmonary hypertension was caused by
inhalation of 5% 02 in rats. Pulmonary vascujar re-
sistance (PVR) increased, but heart rate (HR), cardiac
output (CO) and carotid arterial pressure (CAP) were
not obviously changed. After an intravenous admini-
stration of Radix Angelicae sinensis, the acute
pulmonary hypertension induced by inhalation of 5%
O2 could be attenuated, but this effect disappeared if
propranolol was given before Radix Angelicae sinensis.
In chronic experiments, the same results were
obtained, but the protective effect of Radix Angelicae
sinensis on heart function was not influenced by
propranolol. It is suggested that Radix Angelicae
sinensis rmght play a role by stimulating the
βz-receptor in the prevention of acute and chronic
hypoxic pulmonary hypertension. However, prevention
of hypertrophy of the right ventricle and enhancement
of heart function in chronic hypoxic rats might not be
attributed to the β1 receptor in the heart. 相似文献
4.
Zhi-Qin Mao Mei Sun Department of Pediatrics Second Affiliated Hospital China Medical University Shenyang Liaoning Province China Ying Huang Hong Gao Department of Pediatric Surgery Second Affiliated Hospital China Medical University Shenyang Liaoning Province China Qiang Ruan Rong He Ying Qi Yu-Jing Huang Yan-Ping Ma Yao-Hua Ji Zheng-Rong Sun Virus Laboratory Second Affiliated Hospital China Medical University Shenyang Liaoning Province China 《World journal of gastroenterology : WJG》2007,(32)
AIM:To explore the genetic diversities of UL144 open reading frame (ORF) of cytomegalovirus DNA detected in colon tissue from infants with Hirschsprung's disease (HD) by sequencing UL144 DNA in 23 aganglionic colon tissue and 4 urine samples from 25 HD infants. METHODS:Nest PCR was performed for amplification of the UL144 gene. The UL144 gene was analyzed with softwares,such as DNAclub,BioEdit,PROSITE database,and DNAstar. RESULTS:The strains from HD patients were distributed among three genotypes of UL144:group 1A (64%),group 2 (24%),and group 3 (12%). The UL144 genotypes between strains from HD and control group were compared by chi square test (χ2 = 1.870,P = 0.393). Strains from the colon were sporadically distributed in UL144 genotypes. CONCLUSION:There are genetic diversities of UL144 ORF in colon tissue of infants with HD. However,cytomegalovirus UL144 genotypes are not associated with clinical manifestations of HD. 相似文献
5.
A methoxylated fatty acid that inhibits phospholipase A(2) (PLA(2); EC 3.1.1.4) was purified from the brown seaweed Ishige okamurae. Approximately 8.1 mg of the inhibitory compound, 7-methoxy-9-methylhexadeca-4,8-dienoic acid, was isolated from 1 kg of I. okamurae powder. Recombinant PLA(2) derived from the pathogenic bacterium Vibrio mimicus was used as the target enzyme. The methoxylated fatty acid compound competitively inhibited PLA(2) with a Ki value of 3.9 microg/mL. The concentrations required for 50% inhibition of PLA(2), oedema and erythema were 1.0 microg/mL, 3.6 mg/mL and 4.6 mg/mL, respectively. The compound strongly inhibited PLA(2) activity in vitro and had potent antiinflammatory activity in vivo. 相似文献
6.
Two new diterpenoid alkaloids, flavamine ( 1) and flavadine ( 2), were isolated from the roots of ACONITUM FLAVUM Hand-Mazz. The structures were established on the bases of spectral analyses and chemical correlations with napelline ( 3) and lucidusculine ( 4), respectively. 相似文献
7.
Kangouri K Miyoshi T Kawashima A Ikeda A Mizutani T Omura S Lian-Niang L Hong X 《Planta medica》1989,55(3):297-299
Neokadsuranic acid A, which is the first triterpenoid with the 14(13-->12) ABEO lanostane skeleton, was isolated from KADSURA HETEROCLITA together with (24 Z)-3-oxo-lanosta-8,24-dien-26-oic acid. The present paper deals with the isolation and structure elucidation of these two new compounds. 相似文献
8.
Polylactide (PLA) microspheres were coated with collagen for cell culture and injectable cell carriers. Utilizing a method of emulsion-solvent evaporation, PLA microspheres with diameter ranging from 180 to 280 microm were prepared, followed with aminolysis in hexanediamine/n-propanol solution to introduce free amino groups on their surfaces. After the amino groups were transferred into aldehyde groups by a treatment of glutaraldehyde, collagen type I was covalently coupled via Schiff base formation between the aldehyde groups and the amino groups on collagen molecules. Meanwhile, physically entangled collagen molecules were retained following a grafting-coating protocol to yield microspheres coated with larger amount of collagen. Aminolysis resulted in weight loss of the microspheres following a linear relationship with the aminolysis time. The NH2 and collagen contents existed on the microsphere surface were quantitatively determined by ninhydrin and hydroproline (Hyp) analyses, respectively. Larger amount of collagen was immobilized on the microspheres with higher content of NH2. In vitro chondrocyte culture revealed that the cells could attach, proliferate and spread on these PLA microspheres, in particular on the ones having higher content of collagen. These results show that the collagen-coated PLA microspheres are promising candidate as cell microcarriers. 相似文献
9.
抗hER合成肽单克隆抗体的制备与鉴定 总被引:1,自引:0,他引:1
用合成的人雌激素受体(hER)抗原决定簇多肽(氨基酸序列从151~165)与KLH的偶联物为抗原,免疫BALB/C小鼠,经鼠-鼠杂交,ELISA和免疫细胞化学法筛选,有限稀释克隆化,得到一株分泌抗hER合成肽的杂交瘤细胞株(2B12)。用ELISA法测定。该纯化抗体10ng/ml仍与抗原反应,其免疫球蛋白为IgG2a.k。与MCF-7乳腺癌细胞溶解蛋白的Westernblot分析,在分子量67kD 相似文献
10.
YUN PENG DAI WEN YING YAN BAI JUN SHEN LI JUN CHEN FEI GAO Hong MEI WANG Paediatric Department Shandong Provincial Hospital Shandong University Ji-nan P. R. China Shandong Umbilical Cord Stem Cell Bank Ji-nan P. R. China 《中华微生物学和免疫学杂志(英文版)》2006,4(1):71-75
To investigate the HLA-A, -B allele polymorphism in Han population of Shandong province and to explore the possibility to find out the HLA-A, -B-matched cord blood donors for stem cell transplantation to be used in other area in China, 5844 umbilical cord blood samples were taken from Han population donors of Shandong province, and assayed with PCR-sequence-oligonucleotide (PCR-SSO) assay. In Shandong Han donors, 20 alleles at HLA-A locus and 46 alleles at HLA-B locus could be detected as revealed in the present study. Among the 20 alleles at HLA-A locus, the most prevalent five alleles included A * 02(0.3041), A * 11(0.1443), A * 24(0.1434), A * 30(0.0975) and A * 33(0.0859), while, the alleles with lower gene frequencies included A * 34(0.0006), A * 25 (0.0005), A*66(0.0005), A* 74(0.0004) and A* (0.0001). Of the 46 HLA-B alleles detected, the most prevalent five alleles were B * 13(0.1348), B * 51(0.0713), B * 62(0.0712), B * 61 (0.0676) and B * 60(0.0642); while alleles with lower gene frequencies included B * 77(0.0001), B * 76(0.0002), B * 47(0.0003), B * 42(0.0003) and B * 72(0.0004). In comparison with those of the other Han population in China, the HLA-A, -B gene frequencies in the umbilical cord blood of Shandong province possess unique distribution features among the investigated populations from various regions of the same race origin, and the differences in various regions of the same race were less than those among the different race. It is evident that the HLA-A,-B alleles of the umbilical cord blood taken in Shangdong province show high degree of polymorphism, and it might be part of those of Northern Han population in China. So, it is reasonable for patients of Northern Chinese to receive HLA class I -match transplant of cord blood stem cells for tissue and organ transplantation from Shangdong umbilical cord blood bank. 相似文献