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1.
27Al NMR spectra of an equimolar (10 mM) Al(III)-citrate system were obtained at different temperatures. The linewidths of the signals decreased in the spectra recorded at elevated temperatures, which enabled us to unequivocally identify the resonance lines. From the spectrum recorded at 65 approximately C, a mononuclear Al(III)-citrate complex was identified at a solution pH of 3.0 in addition to trinuclear Al(III)-citrate complex, which dominated at pH 4.0.  相似文献   
2.
5-Fluorouracil derivatives with serum protein binding potencies   总被引:1,自引:0,他引:1  
To develop an optimal delivery system for 5-fluorouracil (5FU) using serum protein as a drug carrier, a series of its benzyl derivatives was synthesized. Then their binding to the serum protein was investigated by equilibrium dialysis. The benzyl derivatives of 5FU were strongly bound to rat plasma protein or human serum albumin. The bound percentage increased with increasing hydrophobicity. It was suggested that the benzyl derivative of 5FU existed in the blood as a complex with serum albumin and circulated for a long time as a polymeric drug does.  相似文献   
3.
Acoustic signals from wild Neophocaena phocaenoides sunameri were recorded in the waters off Liao-dong-wan Bay located in Bohai Sea, China. Signal analysis shows that N. p. sunameri produced "typical" phocoenid clicks. The peak frequencies f(p) of clicks ranged from 113 to 131 kHz with an average of 121+/-3.78 kHz (n=71). The 3 dB bandwidths delta f ranged from 10.9 to 25.0 kHz with an average of 17.5+/-3.30 kHz. The signal durations delta t ranged from 56 to 109 micros with an average 80+/-11.49 micros. The number of cycles N(c) ranged from 7 to 13 with an average of 9+/-1.48. With increasing peak frequency there was a faint tendency of decrease in bandwidth, which implies a nonconstant value of f(p)/delta f. On occasion there were some click trains with faint click energy presenting below 70 kHz, however, it was possibly introduced by interference effect from multiple pulses structures. The acoustic parameters of the clicks were compared between the investigated population and a riverine population of finless porpoise.  相似文献   
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We present recent results on single particle transverse momentum distributions of pions, kaons and protons, measured in CERN Experiment NA44, of 200 AGeV/c S+S and 158 AGeV/c Pb+Pb central collisions. By comparing these data with thermal and transport models, freeze-out parameters like the temperatureT fo and the chemical potentials (μ q ,μ s ) are extracted and discussed.  相似文献   
7.
We perform the first quantitative analysis of the reaction cross sections of {28-32}Ne by {12}C at 240 MeV/nucleon, using the double-folding model with the Melbourne g matrix and the deformed projectile density calculated by antisymmetrized molecular dynamics. To describe the tail of the last neutron of {31}Ne, we adopt the resonating group method combined with antisymmetrized molecular dynamics. The theoretical prediction excellently reproduces the measured cross sections of {28-32}Ne with no adjustable parameters. The ground state properties of {31}Ne, i.e., strong deformation and a halo structure with spin parity 3/2{-}, are clarified.  相似文献   
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Aspergilloglutamic peptidase from Aspergillus niger is a novel pepstatin-insensitive acid endopeptidase distinct from the well-studied aspartic peptidases, and thus is an interesting target for protein structure/function studies. In the present study, we have determined the three-dimensional structure of the enzyme by X-ray crystallography to a 1.4-Å resolution. The results revealed that the enzyme has a unique structure, composed of two seven-stranded anti-parallel β-sheets which form a β-sandwich structure and appear to have a partial two-fold symmetry, suggesting its possible evolution by gene duplication and that the glutamic acid-110 and glutamine-24 in the heavy chain form a catalytic dyad, consistent with our results obtained by site-directed mutagenesis.  相似文献   
10.
Beker  H.  Bøggild  H.  Boissevain  J.  Cherney  M.  Dodd  J.  Esumi  S.  Fabjan  C. W.  Fields  D. E.  Franz  A.  Hansen  K. H.  Holzer  B.  Humanic  T.  Jacak  B.  Jayanti  R.  Kalechofsky  H.  Kobayashi  T.  Kvatadze  R.  Lee  Y. Y.  Leltchouk  M.  Lörstad  B.  Maeda  N.  Medvedev  A.  Miake  Y.  Miyabayashi  A.  Murray  M.  Nagamiya  S.  Nishimura  S.  Noteboom  E.  Pandey  S. U.  Piuz  F.  Polychronakos  V.  Potekhin  M.  Poulard  G.  Sakaguchi  A.  Sarabura  M.  Shigaki  K.  Simon-Gillo  J.  Sletten  H.  Sondheim  W.  Sugitate  T.  Sullivan  J. P.  Sumi  Y.  van Hecke  H.  Willis  W. J.  Wolf  K. 《Zeitschrift fur Physik C Particles and Fields》1994,64(2):209-217
K+K+ and KK correlations from S+Pb collisions at 200 GeV/c per nucleon and K+K+ correlations from p+Pb collisions at 450 GeV/c per nucleon, are presented as measured by the focusing spectrometer of the NA44 experiment at CERN. Multidimensional fits are performed in order to characterize the kaon-emission volume, which is found to be smaller than the pion-emission volume.  相似文献   
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