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41.
Stereoselective determination of cetirizine and studies on pharmacokinetics in rat plasma 总被引:2,自引:0,他引:2
Choi SO Lee SH Kong HS Kim EJ Choo HY 《Journal of chromatography. B, Biomedical sciences and applications》2000,744(1):201-206
Enantiomers may confer benefits over racemates in therapeutic uses and we developed a chiral separation method of cetirizine enantiomers, a second generation H1 histamine receptor antagonist, in rat plasma. alpha1-Acidglycoprotein based chiral stationary phase(AGP-CSP), monitored with UV at 230 nm was used to separate the enantiomers. Observed enantioselectivity (alpha) was 2.0. The AGP-CSP was also used at a preparative scale to isolate the enantiomers with an optical purity of greater than ee 99%. In addition, an analysis was carried out for the cetirizine enantiomers in rat plasma to study the differences of enantiomers in pharmacokinetics. Both (+)- and (-)-cetirizine were separated using a reversed-phase column of AGP, and were detected at the range of 2.5-200 microg ml(-1) in plasma. Although there was no recognizable differences in pharmacokinetics between the enantiomers in rat, the method appears to be useful for their pharmacokinetic studies. 相似文献
42.
This report describes an 11 month old female baby with features of pentasomy X. A molecular and cytogenetic evaluation revealed that her karyotype was 49,XXXXX and her extra X chromosomes were of maternal origin. She has muscular hypotonia, mental retardation, a cleft palate, mild hydrocephalus as a result of dilatation of both lateral ventricles, hyperextensible elbow joints, proximal radioulnar synostosis, clinodactyly of the fifth finger, valgus of the feet, and small hands and feet. In addition, she has a persistent pupillary membrane and congenital chorioretinal atrophy. The pathogenesis of pentasomy X is not clear at present, but it is thought to be caused by successive maternal non-dysjunctions. 相似文献
43.
Yong D Lim JG Choi JR Park Q Yang CH Choi SH Jeong HJ Song KS 《Yonsei medical journal》2000,41(1):136-139
Klinefelter syndrome (KS) is often associated with various neoplasms, especially germ cell tumors. Mediastinum is the most favored site of extragonadal germ cell tumors with KS, which is somewhat different from those without KS. The retroperitoneal germ cell tumor in KS is very rare. A five-month-old boy with an abdominal mass was found to have a retroperitoneal tumor. After surgical removal, he was diagnosed to have mature cystic teratoma. Cytogenetic study of his peripheral lymphocytes revealed that his karyotype was consistent with KS. This case suggests that patients with KS might be at risk of having germ cell tumors in sites other than mediastinum. It also suggests that all cases with these tumors should be screened for the presence of karyotypic abnormalities, and it might help to assess the exact correlation between germ cell tumors and KS, and to treat them accordingly. 相似文献
44.
Byun BH Lee SW Bae SH Choi JY Kim DG Byun JY Park YM Park DH Kim BS 《Journal of Korean medical science》1999,14(1):97-101
Biliary complications after orthotopic liver transplants are a continuing cause of morbidity and mortality. Biliary stones and sludge are less well known complications of hepatic transplantation, although they have long been recognized. Recently we experienced two cases of biliary stones developed after liver transplantation. One 32-year-old male, who frequently admitted due to recurrent cholangitis, was treated with percutaneous transhepatic biliary drainage and choledochojejunostomy with cholecystectomy. The other 58-year-old male, who had stones in commone bile duct, was treated by endoscopic manipulation. They are in good condition without recurrent bile duct stones or its accompanying complications. Although stones and sludge are relatively infrequent after liver transplantation, surgical or interventional radiologic treatments are usually performed for treatment. 相似文献
45.
C K Lee Y S Kwak H Rhee Y S Kim J H Han J O Choi Y H Lee 《Journal of Korean medical science》1987,2(1):19-34
The lifetime prevalences of DSM-III mental disorders using Korean version of DIS-III are presented. They were studied in 5,100 adults (aged 18 to 65) in household selected by two stage cluster sampling. Comparisons were made between regions, sex and age groups. International comparison with Epidemiologic Catchment Area program was also made. 相似文献
46.
DNA restriction profiles of various Gardnerella vaginalis isolates, generated by BamHI, EcoRI, PstI and other restriction enzymes, varied considerably. Only a few DNA fragments were identified as common in ethidium bromide fluorescence profile and Southern-blot hybridization patterns (employing a digoxigenin-labelled G. vaginalis DNA probe and an enzyme-linked immunoassay detection method). While the efficiencies of Southern-blot hybridization appeared inconsistent, in dot-blot assays, DNA from each isolate hybridized readily, enabling the detection of at least 10 ng DNA. A 5.7-kb DNA fragment from G. vaginalis ATCC 14018 genomic library, cloned in the BamHI site of pBR322, could replace the total genomic DNA probe. This specific DNA fragment was present in different sizes in 12 analysed G. vaginalis strains, describing a restriction fragment length polymorphism. In control studies, none of the DNA from bacteria other than G. vaginalis (including some genitourinary tract residents) hybridized with the G. vaginalis total or specific DNA probes. Non-radioactive G. vaginalis DNA probes can thus form the basis of a useful detection method for further studies of this organism. 相似文献
47.
Effects of short-term cholestyramine feeding on cholesterol metabolism in differently aged rats 总被引:1,自引:0,他引:1
The effects of short-term (7 days) feeding of a diet containing cholestyramine (5%) on the cholesterol metabolism were studied in male Sprague-Dawley rats at ages of 5 weeks (young) and 9-10 months (adult). Cholestyramine significantly enhanced the activities of hepatic 3-hydroxy-3-methylglutaryl coenzyme A reductase and cholesterol 7 alpha-hydroxylase both in young and adult rats; however, the absolute values were significantly higher in the former. The time-courses of changes in the activities of these enzymes after cessation of cholestyramine were comparable in both groups of rats. The rate of incorporation of mevalonate into sterol was also higher in young than in adult rats, while the stimulating effect of cholestyramine was markedly greater in adult rats. Hepatic acyl-CoA:cholesterol acyltransferase activity was comparable, but cholestyramine significantly decreased it only in adult rats. In adult rats hepatic cholesterol was decreased significantly by the resin while it remained uninfluenced in young rats. The serum cholesterol level tended to be higher in adult rats regardless of the dietary manipulation. The results indicate an appreciable age-dependent change in the hepatic cholesterol metabolism in response to the interruption of enterohepatic circulation of bile acids. 相似文献
48.
49.
Ten members of two families with D/G translocation, three members of a family with D/D translocation, and one patient with non-familial and one with apparently non-familial D/D translocation were examined. The trdnslocation chromosomes were identified by SH-thymidine labeling and autoradio-graphy as 14q21q and 13q14q, respectively. These findings support the hypothesis of nonrandomness of D group chromosomes involved in centric-fusion translocation. The importance of the identification of Dgroup chromosomes involved in centriofusion translocation in relation to genetic counseling is discussed. 相似文献
50.
Effect of ketamine on apoptosis by energy deprivation in astroglioma cells using flow cytometry system 总被引:3,自引:0,他引:3
Apoptosis is a programmed, physiologic mode of cell death that plays an important role in tissue homeostasis. As for the central nervous system, ischemic insults can induce pathophysiologic cascade of apoptosis in neurophils. Impairment of astrocyte functions during brain ischemia can critically influence neuron survival by neuronglia interactions. We aimed to elucidate the protective effect of ketamine on apoptosis by energy deprivation in astrocytes. Ischemic insults was induced with iodoacetate/ carbonylcyanide m-chlorophenylhydrazone (IAA/CCCP) 1.5 mM/20 microm or 150 microm/2 microm for 1 hr in the HTB-15 and CRL-1690 astrocytoma cells. Then these cells were reperfused with normal media or ketamine (0.1 mM) containing media for 1 hr or 24 hr. FITC-annexin-V staining and propidium iodide binding were determined by using flow cytometry. Cell size and granularity were measured by forward and side light scattering properties of flow cytometry system, respectively. An addition of ketamine during reperfusion increased the proportion of viable cells. Ketamine alleviated cell shrinkage and increased granularity during the early period, and ameliorated cell swelling during the late reperfusion period. Ketamine may have a valuable effect on amelioration of early and late apoptosis in the astrocytoma cells, even though the exact mechanism remains to be verified. 相似文献