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991.
Four new hopane-type saponins, glinusides F, G, H, and I (1-4), and the known succulentoside B (5), as well as the two known flavones 5,7,4'-trihydroxyflavone-6,8-di-C-glucoside (vicenin-2) and 5,7,4'-trihydroxyflavone-8-C-sophoroside (vitexin-2' '-O-glucoside), were isolated from the seeds of Glinus lotoides growing in Ethiopia. On the basis of the spectroscopic data analysis, including 2D NMR and HRESIMS, the new structures were characterized as 3beta-O-beta-D-xylopyranosyl-6alpha-O-beta-D-xylopyranosyl-16beta-O-beta-D-xylopyranosyl-22-hydroxyhopane (1), 3beta-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-xylopyranosyl-6alpha,16beta-dihydroxy-22-O-alpha-L-rhamnopyranosylhopane (2), 3beta-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-xylopyranosyl-6alpha-O-beta-D-xylopyranosyl-16beta-hydroxy-22-O-alpha-L-rhamnopyranosylhopane (3), and 3beta-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-d-xylopyranosyl-6alpha-O-beta-D-xylopyranosyl-16beta-O-beta-D-xylopyranosyl-22-hopane (4). 相似文献
992.
Gastroprotective effect of the Mapuche crude drug Araucaria araucana resin and its main constituents
Schmeda-Hirschmann G Astudillo L Rodríguez J Theoduloz C Yáñez T 《Journal of ethnopharmacology》2005,101(1-3):271-276
The resin from the tree Araucaria araucana (Araucariaceae) has been used since pre-columbian times by the Mapuche amerindians to treat ulcers. The gastroprotective effect of the resin was assessed in the ethanol-HCl-induced gastric ulcer in mice showing a dose-dependent gastroprotective activity at 100, 200 and 300 mg/kg per os. The main three diterpene constituents of the resin, namely imbricatolic acid, 15-hydroxyimbricatolal and 15-acetoxyimbricatolic acid were isolated and evaluated for gastroprotective effect at doses of 50, 100 and 200 mg/kg. A dose-related gastroprotective effect with highly significant activity (P<0.01) was observed at doses up to 200 mg/kg. At 100 mg/kg, the highest gastroprotective activity was provided by 15-hydroxyimbricatolal and 15-acetoxyimbricatolic acid, all of them being as active as the reference drug lansoprazole at 20 mg/kg. The cytotoxicity of the main diterpenes as well as lansoprazole was studied towards human lung fibroblasts (MRC-5) and determined by the MTT reduction assay. A concentration-dependent cell viability inhibition was found with IC50 values ranging from 125 up to 290 microM. Our results support the traditional use of the Araucaria araucana resin by the Mapuche culture. 相似文献
993.
Lifshitz T Levy J Mahler O Levinger S 《Journal of cataract and refractive surgery》2005,31(7):1392-1395
PURPOSE: To report 5 eyes of peripheral sterile corneal infiltrates after refractive surgery. SETTING: Department of Ophthalmology, Soroka University Medical Center, Beer-Sheva, Israel, and Enaim Ophthalmological Center, Jerusalem, Israel. METHODS: Three patients had bilateral refractive procedures for correcting myopia. The procedures included laser epithelial keratectomy in 2 eyes, laser in situ keratomileusis (LASIK) in 2 eyes using a keratome, and LASIK in 1 eye using femtosecond laser. RESULTS: All the patients complained of ocular pain between 1 and 3 days after the procedure. A ring stromal infiltrate peripheral to the flap edge with intact epithelium and an intervening clear zone between the peripheral corneal infiltrates and the limbus was observed in 5 eyes without anterior chamber reaction. All cases improved after several days of topical steroid and antibiotic treatment and systemic steroid. Final visual acuity was 20/25 or better in all cases. CONCLUSIONS: The exact mechanism of this complication is still unknown, which can be confused with infectious keratitis. It is important to maintain a high degree of suspicion for infectious keratitis because the management is very different. The potential outcome can be much worse if the keratitis is due to an infectious etiology which can appear after all types of refractive laser procedures. 相似文献
994.
995.
Lifshitz T Levy J Klemperer I Levinger S 《Journal of refractive surgery (Thorofare, N.J. : 1995)》2005,21(5):494-496
PURPOSE: To report a rare case of late bilateral ectasia developing after LASIK for low myopia without preoperative risk factors. METHODS: A 21-year-old man underwent bilateral uneventful LASIK for low myopia of -2.75 diopters in both eyes. Preoperative corneal pachymetry was 531 microm in the right eye and 526 microm in the left eye. The total ablation depth was 46.8 microm in the right eye and 42.2 microm in the left eye. Preoperative corneal topography was normal and did not reveal forme fruste keratoconus. RESULTS: Twenty-four months postoperatively, the patient developed bilateral inferior keratectasia of +0.50 -3.00 x 72 degrees in the right eye and +1.00 -2.75 x 99 degrees in the left eye. CONCLUSIONS: Late keratectasia may follow LASIK for low myopia despite a thorough preoperative work-up. 相似文献
996.
997.
Shneider BL Bosch J de Franchis R Emre SH Groszmann RJ Ling SC Lorenz JM Squires RH Superina RA Thompson AE Mazariegos GV 《Pediatric transplantation》2012,16(5):426-437
Complications of portal hypertension in children lead to significant morbidity and are a leading indication for consideration of liver transplantation. Approaches to the management of sequelae of portal hypertension are well described for adults and evidence-based approaches have been summarized in numerous meta-analyses and conferences. In contrast, there is a paucity of data to guide the management of complications of portal hypertension in children. An international panel of experts was convened on April 8, 2011 at The Children's Hospital of Pittsburgh of UPMC to review and adapt the recent report of the Baveno V Consensus Workshop on the Methodology of Diagnosis and Therapy in Portal Hypertension to the care of children. The opinions of that expert panel are reported. 相似文献
998.
999.
Slavin TP Lazebnik N Clark DM Vengoechea J Cohen L Kaur M Konczal L Crowe CA Corteville JE Nowaczyk MJ Byrne JL Jackson LG Krantz ID 《American journal of medical genetics. Part A》2012,(6):1481-1485
Cornelia de Lange syndrome (CdLS) is a genetic disorder associated with delayed growth, intellectual disability, limb reduction defects, and characteristic facial features. Germline mosaicism has been a described mechanism for CdLS when there are several affected offspring of apparently unaffected parents. Presently, the recurrence risk for CdLS has been estimated to be as high as 1.5%; however, this figure may be an underrepresentation. We report on the molecularly defined germline mosaicism cases from a large CdLS database, representing the first large case series on germline mosaicism in CdLS. Of the 12 families, eight have been previously described; however, four have not. No one specific gene mutation, either in the NIPBL or the SMC1A gene, was associated with an increased risk for germline mosaicism. Suspected or confirmed cases of germline mosaicism in our database range from a conservative 3.4% up to 5.4% of our total cohort. In conclusion, the potential reproductive recurrence risk due to germline mosiacism should be addressed in prenatal counseling for all families who have had a previously affected pregnancy or child with CdLS. 相似文献
1000.