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991.
Rapid and sensitive determination of sertraline in human plasma using gas chromatography-mass spectrometry 总被引:3,自引:0,他引:3
Kim KM Jung BH Choi MH Woo JS Paeng KJ Chung BC 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2002,769(2):333-339
A method for the determination of sertraline in human plasma using gas chromatography-mass spectrometry (GC-MS), with the selected ion-monitoring (SIM) mode, was described. The following was used in this study: (1) single liquid-liquid extraction at alkaline pH after deproteinization of plasma protein and (2) perfluoroacylation with HFBA, which has higher sensitivity (about 10-fold) compared with previous reported derivatization. The detection limit for the SIM of sertraline as an N-HFB derivative was 0.1 ng/ml, and its recovery was 80-85%. The linear response was obtained in the range of 0.2-10.0 ng/ml with a correlation coefficient of 0.999. The coefficient of variation (C.V.%) was less than 12.1% in the 1-30 ng/ml, and less than 18.2% at 0.2 ng/ml, and the accuracy was less than 10% at all of the concentration range. These findings indicate that this assay method has adequate precision and accuracy to determine the amount of sertraline in human plasma. After pharmacokinetics was performed with this assay method following oral administration of sertraline hydrochloride in man, moment analysis revealed that pharmacokinetic parameters for sertraline (Cmax, 10.3 ng/ml; Tmax, 8.0 h; T(1/2) 28.6 h) were similar to previously reported results. These results indicate that this simple and sensitive assay method is readily applicable to the pharmacokinetic studies of sertraline. 相似文献
992.
993.
KIM Heung Chul Oscar S. FRIENDLY Jason G. PIKE Anthony L. SCHUSTER Monica L. O'GUINN Terry A. KLEIN 《Entomological Research》2003,33(3):189-201
ABSTRACT Adult mosquito surveillance was conducted during 2001 at 28 US military installations and training sites located in five provinces in the Republic of Korea (ROK). Adult mosquitoes were collected in New Jersey and dry ice-baited CDC-type light traps from 1 May through 15 October. Mosquito surveillance was conducted to determine threshold levels to initiate pesticide applications and identify malaria infection rates at selected Army installations and training sites. A total of 61,584 adults [45,814 (74.4%) females and 15,770 (25.6%) males] comprising 17 species and 7 genera were collected during 2001. The most common species collected were Anopheles sinensis Wiedemann (36.3%), Aedes vexans nipponii (Theobald) (23.1%), Culex tritaeniorhynchus Giles (22.3%) and Culex pipiens Coquillett (17.6%). Trap indices (TIs) varied widely for species over their range, due in part, to geographical distribution and degree of association with urban communities. During 2001, the TI for An. sinensis was 19.6 females/trap night compared to years 1999 and 2000, when the TI for the Munsan area was 1.4 and 2.9 times (27.7 and 57.4 TI) greater, respectively. The weekly population densities for some species were variable for each of the years, apparently as a result of variable annual weather conditions. None of the 16,302 Anopheles sinensis assayed for plasmodium vivax (Pv) malaria infections by Enzyme Linked Immunosorbent Assay (ELISA) were positive. 相似文献
994.
SUH Eun Young Kwang Hee SON Dong Ha SHIN Ki Duk KIM Cheol JANG Yong Man YU Ho-Yong PARK 《Entomological Research》2002,32(3):133-139
ABSTRACT A new insect pathogenic fungi, Paecilomyces licacinus HY-4 that was isolated from soil sample, showed biological activity to Chestnut Brown Chafer, pest of golf course. The culture condition for the fungi P. lilacinus HY-4 was optimized through statistical approach for the mass production. According th the bioassay on the pest, the insecticidal activity reached up to 30%, and positive factor for the production of the fungi was zeolite with 97.5% of significance. 相似文献
995.
996.
ABSTRACT Monoclonal antibodies against the myosin heavy chain of Amoeba proteus were obtained and used to localize myosin inside amoebae and to clone cDNAs encoding myosin. Myosin was found throughout the amoeba cytoplasm but was more concentrated in the ectoplasmic regions as determined by indirect immunofluorescence microscopy. In symbiont-bearing xD amoebae, myosin was also found on the symbiosome membranes, as checked by indirect immunofluorescence microscopy and by immunoelectron microscopy. The open reading frame of a cloned myosin cDNA contained 6,414 nucleotides, coding for a polypeptide of 2,138 amino acids. While the amino-acid sequence of the globular head region of amoeba's myosin had a high degree of similarity with that of myosins from various organisms, the tail region building a coiled-coil structure did not show a significant sequence similarity. There appeared to be at least three different isoforms of myosins in amoebae, with closely related amino acids in the globular head region. 相似文献
997.
Kinetic resolution for optically active epoxides by microbial enantioselective hydrolysis 总被引:8,自引:0,他引:8
Won Jae Choi Eun Chul Huh Hyoung Jun Park Eun Yeol Lee Cha Yong Choi 《Biotechnology Techniques》1998,12(3):225-228
Resolution of several racemic epoxides was accomplished using an epoxide hydrolase activity of whole cells of the newly isolated Aspergillus niger. (S)-Styrene oxide, for example, was obtained from its racemates with optical purity of 100% ee and 32% yield. © Rapid Science Ltd. 1998 相似文献
998.
Metabolic engineering of Pseudomonas putida for the simultaneous biodegradation of benzene, toluene, and p-xylene mixture 总被引:1,自引:0,他引:1
For the complete biodegradation of a mixture of benzene, toluene, and p-xylene (BTX), a critical metabolic step that can connect two existing metabolic pathways of aromatic compounds (the tod and the tol pathways) was determined. Toluate-cis-glycol dehydrogenase in the tol pathway was found to attack benzene-cis-glycol, toluene-cis-glycol, and p-xylene-cis-glycol, which are metabolic intermediates of the tod pathway. Based on this observation, a hybrid strain, Pseudomonase putida TB101, was constructed by introduction of the TOL plasmid pWW0 into P. putida F39/D, a derivative of P. putida F1, which is unable to transform cis-glycol compounds to corresponding catechols. The metabolic flux of BTX into the tod pathway was redirected to the tol pathway at the level of cis-glycol compounds by the action of toluate-cis-glycol dehydrogenase in P. putida TB101, resulting in the simultaneous mineralization of BTX mixture without accumulation of any metabolic intermediates. The profile of specific degradation rates showed a similar pattern as that of the specific growth rate of the microorganism, and the maximum specific degradation rates of benzene, toluene, and p-xylene were determined to be about 0.27, 0.86, and 2.89 mg/mg biomass/h, respectively. P. putida TB101 is the first reported microorganism that mineralizes BTX mixture simultaneously. (c) 1994 John Wiley & Sons, Inc. 相似文献
999.
Keepyung Nahm Won Sup Kim Kwang Yul Moon 《Bioorganic & medicinal chemistry letters》1993,3(12):2631-2634
Quinolone antibiotic compounds having no carboxylic group but its equivalents at the 3-position have been synthesized. Energies of tautomers with the carboxylic mimics were calculated in gas phase and aqueous solution with AM1-SCRF method. Antibacterial activity of the compounds was rationalized with tautomeric protons and atomic charges of calculated tautomers. 相似文献
1000.
Nitrosyl derivatives of polyoxomolybdates have been synthesized and characterized by X-ray diffraction. Most of them contain the MoII(NO)3+ unit and their structures are related to the following structural types: Lindqvist, Keggin and decatungstate [W10O32]4–. Reductive nitrosylation of (NBu4)4[-Mo8O26] by hydroxylamine in methanol yields (NBu4)2[Mo5O13(OMe)4(NO){Na(MeOH)}]. 3MeOH, which is a versatile reagent yielding a variety of derivatives (i) by the transformation of [Mo5O13(OMe)4(NO)]3– into [Mo6O18(NO)]3– in acetonitrile, (ii) by the formation of [PMo12O39(NO)]4– by reaction of [Mo5O13(OMe)4(NO)]3– with [PMO12O40]3– in basic condition and (iii) by the formation of mixed valence MoVI/MoV/MoII decamolybdates [Mo10O24(OMe)7(NO)]2–, [Mo10O25(OMe)6(NO)]– and [Mo10O20(OMe)9(NO)3]2– by chemical reduction of [Mo5O13(OMe)4(NO)]3–; MoII is localized while MoV are delocalized in the first two species but localized in the third. The unique ligating properties of [Mo5O13(OMe)4(NO)]3– have been documented: this species acts as a tetradentate ligand in [Ce{Mo5O13(OMe)4(NO)}2]2–, a symmetrically tetraligating ligand in [Rh2Cp*2(-Br){-Mo5O13(OMe)4(NO)}] and a bidentate ligand in [Mo5O13(OMe)4(NO){RhCp*(H2O)}]–. Some polyoxomolybdates of the type [Mo5(NO)2O12{RC(NH2)NHO}2{RC(NH)NO}2]2–, which contain the Mo0(NO)
2
2+
unit, have also been characterized. 相似文献