Search Results - (Author, Cooperation:W. Fong)
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1Latest Papers from Table of Contents or Articles in PressA. Rest ; J. L. Prieto ; N. R. Walborn ; N. Smith ; F. B. Bianco ; R. Chornock ; D. L. Welch ; D. A. Howell ; M. E. Huber ; R. J. Foley ; W. Fong ; B. Sinnott ; H. E. Bond ; R. C. Smith ; I. Toledo ; D. Minniti ; K. Mandel
Nature Publishing Group (NPG)
Published 2012Staff ViewPublication Date: 2012-02-18Publisher: Nature Publishing Group (NPG)Print ISSN: 0028-0836Electronic ISSN: 1476-4687Topics: BiologyChemistry and PharmacologyMedicineNatural Sciences in GeneralPhysicsPublished by: -
2Articles: DFG German National LicensesLeung, B. H. ; Fong, W. K. ; Zhu, C. F. ; Surya, Charles
[S.l.] : American Institute of Physics (AIP)
Published 2002Staff ViewISSN: 1089-7550Source: AIP Digital ArchiveTopics: PhysicsNotes: We report detailed investigations of low-frequency excess noise in GaN thin-film cross-bridge structures deposited by rf-plasma assisted molecular-beam epitaxy on top of an intermediate-temperature buffer layer (ITBL) grown at 690 °C. The experimental data indicates strong dependence of the voltage noise power spectra on the thickness of the ITBL with an optimal thickness of 800 nm. A model has been presented to account for the observed noise, which stipulates that the phenomenon arises from the thermally activated trapping and detrapping of carriers. The process results in the correlated fluctuations in both the carrier number and the Coulombic scattering rate. Detailed computation shows that number fluctuation dominates in our samples. Our numerical evaluation indicates a reduction in the trap density by over an order of magnitude with the use of an ITBL in the growth of GaN thin films. © 2002 American Institute of Physics.Type of Medium: Electronic ResourceURL: -
3Articles: DFG German National LicensesShin, W.-W. ; Fong, W.-F. ; Pang, S.-F. ; Wong, Patrick C.-L.
Oxford, UK : Blackwell Publishing Ltd
Published 1985Staff ViewISSN: 1471-4159Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: MedicineNotes: Abstract: Transport of polyamines across the blood-brain barrier of adult rats was examined by measuring the amount of radioactivity that reached the forebrain 5 s after a “bolus’ intracarotid injection. The values were expressed by the brain uptake index (BUI), which is the percentage of material transported in relation to freely diffusible water in a single passage through the brain. Transport was restricted as indicated by the respective BUI values, presented as means ± SD (number of animals): putrescine, 5.3 ± 0.8 (11); spermidine, 6.1 ± 1.3 (7); and spermine, 5.8 ± 0.5 (4). A kinetic study of the transport of [14C]putrescine showed that transport due to passive diffusion accounted for the majority of the observed influx (66% at 1 mM putrescine). However, a small saturable component exists with a Km value of 4–5 mM and a Vmax of 30 nmol ± min−1± g−1. This Km value is considerably higher than the circulating levels of the polyamine in the normal mature animal, and thus is unlikely to be of physiological significance. Competition studies indicated that putrescine does not interact with carriers for adenosine, arginine, choline, or leucine.Type of Medium: Electronic ResourceURL: -
4Articles: DFG German National LicensesChan, H. L.-Y. ; Sung, J. J.-Y. ; Fong, W.-F. ; Chim, A. M.-L. ; Yung, P.-P. ; Hui, A. Y. ; Fung, K.-P. ; Leung, P.-C.
Oxford, UK : Blackwell Science Ltd
Published 2003Staff ViewISSN: 1365-2036Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: MedicineNotes: Background : Previous studies suggested that Phyllanthus species have an anti-viral effect on hepatitis B, but methodologies have been inadequate.Aims : This study aimed to investigate the anti-viral effect of Phyllanthus urinaris.Methods : Chronic hepatitis B patients with positive hepatitis B e-antigen (HBeAg), hepatitis B virus (HBV) DNA 〉 500 000 copies/mL and elevated alanine transaminase (ALT) were recruited. Patients were randomized into groups of 12 receiving P. urinaris 1, 2 and 3 g three times daily for 6 months or placebo (six cases). The primary endpoint was HBV DNA reduction, and secondary endpoints were HBeAg seroconversion and ALT normalization.Results : On an intention-to-treat analysis there was no difference in log10[HBV DNA] reduction of the Phyllanthus 1-g (0.18 ± 1.42), 2-g (0.33 ± 1.08) and 3-g (0.85 ± 1.30) groups vs. placebo (0.28 ± 0.85) (P = 0.90, 0.92 and 0.38, respectively) at the end of treatment. The percentage of patients among the placebo, Phyllanthus 1-g, 2-g and 3-g groups undergoing HBeAg seroconversion (0%, 9.1%, 8.3% and 16.7%, respectively) and ALT normalization (0%, 0%, 8.3% and 33.3%) were not significantly different at the end of treatment. No delayed virological or biochemical response was documented at 24 weeks after the cessation of treatment. No serious adverse event was reported.Conclusion : P. urinaris treatment for 6 months has no demonstrable anti-viral effect in chronic hepatitis B.Type of Medium: Electronic ResourceURL: -
5Articles: DFG German National LicensesStaff View
ISSN: 0005-2744Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: BiologyType of Medium: Electronic ResourceURL: -
6Articles: DFG German National LicensesStaff View
ISSN: 0020-711XSource: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: BiologyChemistry and PharmacologyType of Medium: Electronic ResourceURL: -
7Articles: DFG German National LicensesStaff View
ISSN: 0020-1790Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: BiologyType of Medium: Electronic ResourceURL: -
8Articles: DFG German National LicensesStaff View
ISSN: 0022-1910Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: BiologyType of Medium: Electronic ResourceURL: -
9Articles: DFG German National LicensesStaff View
ISSN: 0022-1910Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: BiologyType of Medium: Electronic ResourceURL: -
10Articles: DFG German National LicensesStaff View
ISSN: 0006-291XSource: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: BiologyChemistry and PharmacologyPhysicsType of Medium: Electronic ResourceURL: -
11Articles: DFG German National LicensesStaff View
ISSN: 0968-0004Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: BiologyChemistry and PharmacologyMedicineType of Medium: Electronic ResourceURL: -
12Articles: DFG German National LicensesPeterson, R.J. ; Hoibraten, S. ; Ouyang, J. ; Braunstein, M.R. ; Chen, X.Y. ; Kohler, M.D. ; Kriss, B.J. ; Mercer, D.J. ; Prout, D.L. ; Oakley, D.S. ; Fong, W.
Amsterdam : ElsevierStaff ViewISSN: 0370-2693Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: PhysicsType of Medium: Electronic ResourceURL: -
13Articles: DFG German National LicensesStaff View
ISSN: 0304-4165Keywords: (Human) ; Dehydrogenase ; Metalloenzyme ; Monoclonal antibodySource: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: BiologyChemistry and PharmacologyMedicinePhysicsType of Medium: Electronic ResourceURL: -
14Articles: DFG German National LicensesStaff View
ISSN: 0305-0491Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: BiologyChemistry and PharmacologyType of Medium: Electronic ResourceURL: -
15Articles: DFG German National LicensesStaff View
ISSN: 0305-0491Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: BiologyChemistry and PharmacologyType of Medium: Electronic ResourceURL: -
16Articles: DFG German National LicensesStaff View
ISSN: 0305-0491Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: BiologyChemistry and PharmacologyType of Medium: Electronic ResourceURL: -
17Articles: DFG German National LicensesStaff View
ISSN: 0305-0491Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: BiologyChemistry and PharmacologyType of Medium: Electronic ResourceURL: -
18Articles: DFG German National LicensesStaff View
ISSN: 0040-4039Keywords: Five-membered aza sugars ; fucosidase ; fucosyltransferase ; inhibitorsSource: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: Chemistry and PharmacologyType of Medium: Electronic ResourceURL: -
19Articles: DFG German National LicensesStaff View
ISSN: 1573-2932Source: Springer Online Journal Archives 1860-2000Topics: Energy, Environment Protection, Nuclear Power EngineeringNotes: Abstract The concentrations of methylmercury (MeHg) in 124 samples of muscle taken from nine species of common sharks of varying sizes and locations along the Florida coast were determined. Muscle MeHg levels averaged 0.88 μg/g (wet sample basis) and ranged from 0.06 to 2.87 μg/g, with 33.1% of the samples exceeding the U.S. Food and Drug Administration's 1 μg/g action level. Differences were found in MeHg concentration by species but not by sex. A positive correlation between MeHg levels and shark size was found such that most sharks larger than approximately 200 cm total length contained MeHg concentrations exceeding the 1 μg/g action level. Fetal sharks contained consistently lower MeHg levels than their mothers. Sharks collected off southern regions of the state contained significantly higher MeHg concentrations than those off the northeast coast. The human health concerns for consumers of Florida shark meat are discussed in relation to these findings.Type of Medium: Electronic ResourceURL: -
20Articles: DFG German National LicensesCanellakis, E. S. ; Kyriakidis, D. A. ; Rinehart, C. A. ; Huang, S. -C. ; Panagiotidis, C. ; Fong, W. -F.
Springer
Published 1985Staff ViewISSN: 1573-4935Source: Springer Online Journal Archives 1860-2000Topics: BiologyChemistry and PharmacologyNotes: Abstract This review considers the role of antizyme, of amino acids and of protein synthesis in the regulation of polyamine biosynthesis. The ornithine decarboxylase of eukaryotic ceils and ofEscherichia coli coli can be non-competitively inhibited by proteins, termed antizymes, which are induced by di-and poly- amines. Some antizymes have been purified to homogeneity and have been shown to be structurally unique to the cell of origin. Yet, the E. c o l i antizyme and the rat liver antizyme cross react and inhibit each other's biosynthetic decarboxylases. These results indicate that aspects of the control of polyamine biosynthesis have been highly conserved throughout evolution. Evidence for the physiological role of the antizyme in mammalian cells rests upon its identification in normal uninduced cells, upon the inverse relationship that exists between antizyme and ornithine decarboxylase as well as upon the existence of the complex of ornithine decarboxylase and antizyme in vivo. Furthermore, the antizyme has been shown to be highly specific; its Keq for ornithine decarboxylase is 1.4 x 1011 M-1. In addition, mammalian ceils contain an anti-antizyme, a protein that specifically binds to the antizyme of an ornithine decarboxylase-antizyme complex and liberates free ornithine decarboxylase from the complex. In B. coli , in which polyamine biosynthesis is mediated both by ornithine decarboxylase and by arginine decarboxylase, three proteins (one acidic and two basic) have been purified, each of which inhibits both these enzymes. They do not inhibit the biodegradative ornithine and arginine decarboxylases nor lysine decarboxylase. The two basic inhibitors have been shown to correspond to the ribosomal proteins S20/L26 and L34, respectively. The relationship of the acidic antizyme to other known B. coli proteins remains to be determined.Type of Medium: Electronic ResourceURL: