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571.
AIM:To isolate,characterize and investigate the antifungal activity of the root bark of Psorospermum corymbiferum(Clusiaceae).METHODS:The finely ground root bark of Psorospermum corymbiferum was cold-extracted by percolation with 98% ethanol(5.0 L) for two weeks.The ethanol extract was macerated with n-hexane,chloroform,ethylacetate and methanol successively to give the respective solvent extracts.Fractionation of the extract was done using column chromatography on silica gel with cyclohexene:ethylacetate(1... 相似文献
572.
Caruso G Martegani A Aiani L Borghi C Verderame F Campisi A Salvaggio G Lagalla R Cardinale AE 《La Radiologia medica》2007,112(1):56-63
PURPOSE: The aim of this paper was to report a heterogeneous late-phase hepatic enhancement pattern observed after administration of a sonographic contrast agent and to present an aetiological hypothesis for the phenomenon. MATERIALS AND METHODS: A total of 1,729 (1,012 women and 717 men; age range 28-82; mean age 51) patients underwent contrast-enhanced sonography of the liver. The examination was performed with a low mechanical index (MI <0.09) after injection of sulphur-hexafluoride-filled microbubbles, using different sonographic equipment and different contrast-specific algorithms. RESULTS: Heterogeneous delayed liver enhancement was observed in six patients in the late phase (180 s), with the presence of multiple, partially confluent, hyperechoic areas peripheral to the portal vessels. The pattern appeared spontaneously between 1 and 4 h after the examination and was associated with the presence of an anomalous echogenicity in the superior mesenteric vein. No patient experienced adverse reactions. CONCLUSIONS: The phenomenon of heterogeneous hepatic enhancement may be related to gas from the intestinal microcirculation being transported to via the enteroportal circulation and becoming trapped in the hepatic sinusoids. 相似文献
573.
G Merino R Real MF Baro L Gonzalez-Lobato JG Prieto AI Alvarez MM Marques 《Drug metabolism and disposition》2009,37(1):5-9
ATP-binding cassette transporter ABCG2 [breast cancer resistance protein (BCRP)] is a member of the ABC transporter superfamily that actively extrudes xenotoxins from cells and is a major determinant of the bioavailability of many compounds. ABCG2 expression is strongly induced during lactation in the mammary gland and is related to the active secretion of drugs into the milk. The presence of drug residues and environmental pollutants in milk is an outstanding problem for human milk consumption and milk industrial processes, involving important risks to public health and the dairy industry. In cows, a single nucleotide polymorphism (SNP) in this protein has been described previously (Tyr581) and is associated with higher fat and protein percentages and lower milk yield. However, whether this amino acid substitution affects ABCG2-mediated drug transport in cows, including milk secretion, required further exploration. We cloned the two variants of bovine ABCG2 and evaluated the effect of this SNP on mitoxantrone accumulation assays performed in ovine primary fibroblasts transiently expressing either of the variants. It is interesting to note that statistically significant differences in activity between both variants were observed, and the Ser581 variant was related with an increased efflux activity. In addition, we demonstrated that genistein is a very good inhibitor of bovine ABCG2 and identified new inhibitors of the transporter, such as the macrocyclic lactones, ivermectin, and selamectin. Moreover, the inhibitory effect of these compounds on human and murine ABCG2 homologs was confirmed using transduced Marbin-Dabin canine kidney II cells. These findings may have important implications regarding the presence of drug residues in milk and drug interactions affecting the pharmacological behavior of ABCG2 substrates. 相似文献
574.
Elegance TP Lam Cindy LK Lam CL Lai MF Yuen Daniel YT Fong Thomas MK So 《Health and quality of life outcomes》2009,7(1):52
Background
Few studies have evaluated the health-related quality of life (HRQOL) of Southern Chinese with chronic hepatitis B (CHB) infection. 相似文献575.
576.