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931.
A simple, rapid, and efficient method was developed to isolate and purify pre-S2 containing HBsAgs from the plasma of a single
chronic carrier of HBsAg (adw) by ammonium sulfate fractionation, hydroxyapatite column chromatography, and polymerized human
serum albumin-affinity column chromatography. About 500 μg of pre-S2 containing HBsAg was obtained from 140 mL of plasma containing
4,200 μg of HBsAg. Two purified pre-S2 containing HBsAgs were analyzed by SDS-polyacrylamide gel electrophoresis and their
molecular weights were determined to be 31,000 and 68,000 respectively. No significant amount of HBsAg or its derivative was
detected in the final product. 相似文献
932.
Kun-Rung Lin Li-Chung Kuo Man-kit Leung Kuo-Huang Hsieh 《European Polymer Journal》2007,43(10):4279-4288
Polymeric light-emitting diodes (PLEDs) using high-performance hole-transport polyurethanes (PUs) have been fabricated. The PUs were prepared from the condensation polymerization of (E, E)-1,4-bis(2-hydroxystyryl)benzene, an oligo para-phenylene-(E)-vinylene (OPV) unit, with toluene diisocyanate (TDI), isophorone diisocyanate (IPDI) or dicyclohexylmethane 4,4′-diisocyanate (H12MDI), respectively. The condensation polymerization was end-capped with 4-tert-butylphenol as the terminal group. The PLED having the PU layer inserted between PEDOT:PSS (HIL) and MEH-PPV (EML) demonstrated superior current efficiency and low turn-on voltage when comparing to the reference devices of ITO/MEH-PPV(50 nm)/Ca(10 nm)/Ag(100 nm) as well as ITO/PEDOT:PSS(30 nm)/MEH-PPV(50 nm)/Ca(10 nm)/Ag(100 nm). In particularly, the best device performance was realized with the PU of OPV-IPDI as the hole-transport layer, resulting 53 times and 2.72 times of current efficiency enhancement as well as 1.5 V and 1 V voltage reduction of the turn-on voltage, respectively, when compared against the reference devices. Besides, our experiments also showed that the PU polymer could also be applied for flexible PLED with similar performance enhancement. Based on the promising results, we concluded that OPV-IPDI was a good hole-transport material for light-emitting diode application. 相似文献
933.
Shyh-Jen Wang Tsai-Yueh Lo Bor-Tsung Hsieh Kai-Yuan Cheng Wan-Yu Lin Lie-Hang Shen Ming-Ja Su 《Journal of Radioanalytical and Nuclear Chemistry》2004,261(1):189-193
A new method for the synthesis of 188Re-Lipiodol without using a chelating agent and to evaluate the stability and biodistribution of the new agent in rats with
hepatic tumors was attempted. Eighteen male Sprague -Dawley rats with liver tumors were sacrificed at 1, 24, and 48 hours
(six rats at each time) after injection of approximately 7.4 MBq (0.2 mCi) of 188Re Lipiodol via the hepatic artery. Samples of tumor, liver and other organs were collected and tissue concentration (%ID/g)
of the markers were calculated. Our data showed a high level of radioactivity in the hepatic tumors at every time of the study.
The ratios of tumor to normal liver tissue concentration (T/N ratio) were 7.62 at 1 hour, 8.03 at 24 hours, and 7.70 at 48
hours. Except for the liver, kidneys and lungs, concentrations in other organs were low. The new method for labeling Lipiodol
with 188Re is simple and has potential for the treatment of hepatic tumors
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
934.
The crystal structures of N-benzamido-meso-tetraphenylporphyrin (NHCOC(6)H(5)-Htpp; 1), (N-benzimido-meso-tetraphenylporphyrinato)(methanol)zinc(II) [Zn(N-NCOC(6)H(5)-tpp)(MeOH); 2(MeOH)], and (acetato)(N-benzamido-meso-tetraphenylporphyrinato)cadmium(II) [Cd(N-NHCOC(6)H(5)-tpp)(OAc); 3] were established. The coordination sphere around Zn(2+) ion in 2(MeOH) is a distorted trigonal bipyramid with N(2), N(5), and O(2) lying in the equatorial plane, whereas, for Cd(2+) ion in 3, it is a sitting-atop derivative with a distorted trigonal bipyramidal geometry in which the apical site is occupied by atoms N(2) and O(2). Cd in 3 acquires five-coordination with five strong bonds [Cd(1)-N(1) = 2.319(5) A, Cd(1)-N(2) = 2.252(5) A, Cd(1)-N(3) = 2.332(5) A, Cd(1)-O(2) = 2.292(5) A, and Cd(1)-O(3) = 2.317(5) A] and with one secondary intramolecular interaction [Cd(1)...N(4)]. The porphyrin ring in these two complexes is distorted to a large extent. The plane of the three pyrrole nitrogen atoms [i.e., N(1)-N(3)] strongly bonded to Zn(2+) in 2(MeOH) and to Cd(2+) in 3 is adopted as a reference plane 3N. For the Zn(2+) complex, the pyrrole nitrogen bonded to the benzamido (BA) ligand lies in a plane with a dihedral angle of 33.8 degrees with respect to the 3N plane, but for the Cd(2+) complex, this dihedral angle is found to be 31.4 degrees. In the former complex, Zn(2+) and N(5) are located on the different side at -0.08 and 1.39 A from its 3N plane, and in the latter one, Cd(2+) and N(5) are also located on the different side at 1.08 and -1.51 A from its 3N plane. VT NMR ((1)H and (13)C) studies of 3 show that the acetate acts as a bidentate ligand and the OAc(-) exchange does not occur in CD(2)Cl(2). Moreover, the NH proton [i.e., H(5)] of 3 in CD(2)Cl(2) is observed as a sharp singlet at delta = -1.13 ppm with Delta nu(1/2) = 4 Hz at 20 degrees C indicating that the intermolecular proton exchange between water and NH proton is rapid. 相似文献
935.
A novel nomenclature for the hypervariable microsatellite DNA, APOAI1 locus, is proposed. The complex nature of the repeat unit in this locus results in alleles separated by a single base. Polymerase chain reaction (PCR) products amplified from this locus were separated by single-strand conformation polymorphism (SSCP) electrophoresis. All the single-stranded DNA bands on the SSCP gel were removed from the gel and a second amplification performed. Homozygous DNA fragments amplified from single-stranded DNA were sequenced. From the 100 individuals studied, 30 alleles and 73 genotypes were found. A system of nomenclature for the APOAI1 locus is provided that is logical and in line with previous models. Using the primers described, the locus can be amplified and alleles designated on the basis of size. This system of nomenclature will assist in the exchange of data between laboratories for this locus. 相似文献
936.
Improving the Ring‐opening Polymerization of l‐Lactide Using n‐Butyl Lithium with Various Bidentate Ligands
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Hsuan‐Ying Chen Yen‐Tzu Huang Jaya Kishore Vandavasi Yu‐Hsieh Chen Chia‐Hao Kuei 《中国化学会会志》2016,63(10):859-863
A series of bidentate ligands were examined to improve the catalytic activity of l ‐lactide (LA) polymerization by using n‐butyl lithium and BnOH. For LA polymerization, n‐butyl lithium with tetraisopropyl methylenebis(phosphonate) (L8 ) showed the greatest catalytic activity but with poor controllability of the polymer molecular weight. The polydispersity indices (PDIs) could be improved without BnOH addition, but Mn GPC was much different from the Mn Cal . 1H NMR spectra confirmed that the cyclized PLA was obtained, thus implying that active chain‐end mechanisms were operative in LA polymerization. 相似文献
937.
In this paper, a new optical material application and a heterodyne interferometer are proposed for measuring small angles. In the proposed interferometer, the optical material is a (1 0 0) silicon wafer applied to compose a new architecture of small angle sensor. The small angle measurement used the phase difference which is dependent on the incident angle at the silicon wafer surface to deduce the angular variation. The proposed architecture is simple and uses the common path method to compare test and reference signals; thus, small angles can be easily and accurately measured by estimating the phase difference. The experimental results demonstrate the feasibility of this method. The angular resolution and sensitivity levels superior to 7 × 10?5° (1.3 × 10?6 rad) and 150 (deg/deg), respectively, were attainable in a dynamic range of 0.45°. 相似文献
938.
Chemical constituents from the leaves of Michelia alba 总被引:1,自引:0,他引:1
939.
Cheng Ming-Jen Wu Ming-Der Hsieh Sung-Yuan Chen Chung-Yi Chen Jih-Jung Kuo Yueh-Hsiung 《Chemistry of Natural Compounds》2022,58(3):471-473
Chemistry of Natural Compounds - An icetexane diterpenoid, 9(10→20)-abeo-abietane diterpenoid, annlomultialaskoside (1), has been isolated from the endophytic fungus Annulohypoxylon... 相似文献
940.
Cheng Ming-Jen Wu Ming-Der Chen Chung-Yi Hsieh Sung-Yuan Chen Jih-Jung 《Chemistry of Natural Compounds》2021,57(6):1032-1034
Chemistry of Natural Compounds - Investigation of the ethyl acetate-soluble layer from the liquid fermentation of Phialophora lagerbergii, an endophytic fungus isolated from the Taiwanese endemic... 相似文献