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41.
The three forms of enterostatin (Ala-Pro-Gly-Pro-Arg, Val-Pro-Gly-Pro-Arg, and Val-Pro-Asp-Pro-Arg), pentapeptides known to inhibit fat-intake, were resolved on a C18 reversed-phase column using a ternary mobile phase consisting of methanol, acetonitrile, and water. Coupled with MS/MS detection, the method has been applied to identify enterostatin sequences in human cerebrospinal fluid and rat brain tissue. Ala-Pro-Gly-Pro-Arg (APGPR) was found to be the predominant enterostatin sequence in both cases. The levels of APGPR were 98.3±16.3 ng/ml in human cerebrospinal fluid and 30.1±12.6 ng/g wet tissue in rat brain, respectively. 相似文献
42.
A. S. Ghosh P. S. Mazumdar Madhumita Basu 《Zeitschrift für Physik A Hadrons and Nuclei》1984,319(1):13-16
The total ionization cross section in electron-hydrogen scattering in the energy range 20.4–68.0 eV has been calculated by a method in which the initial state of the system is treated by a distorted wave polarized orbital method and the final state is described by (1) a product of two unscreened Coulomb functions and (2) a product of a plane wave and a Coulomb function. The corresponding two sets of results using a plane wave in the incident channel have also been reported. The present results where both the electrons are represented by Coulomb waves are in closer agreement than other theoretical predictions With measured values. 相似文献
43.
P. G. Oza H. S. Mazumdar A. K. Choudhary K. Gopalan 《Journal of Chemical Sciences》1984,93(2):189-193
A microcomputer system has been designed for semi-automatic operation of a solid source mass spectrometer used for geochronological
studies. It sequentially steps the magnetic field through pre-selected values, reads the digitized ion currents for a given
time and temporarily stores the data which can be transferred to a paper tape or directly to a desk top calculator for further
analysis. The unit is relatively inexpensive, made of readily available components and can be adapted to many laboratory automation
tasks 相似文献
44.
Functionalization of 4-methyl group in cycloartane-type triterpenoids has been accomplished utilizing, in the key step, photolytic decomposition of an hypoiodite derived from a 3β-hydroxymethyl-4,4-dimethyl precursor. The synthesis of cycloeucalanone from cyclolaudanone is reported. 相似文献
45.
The calculation of general three-dimensional heavy-atom phases, without assumption of heavy-atom sites, using the tangent formula is investigated. Phases obtained in this way have an average difference of 27 ° as compared with phases calculated for the known heavy-atom constellation in the K2PtCl6 derivative of ribonuclease in space groupP21. Five out of eight of the phase sets produce the correct heavy atom positions by calculation of .E maps. 相似文献
46.
47.
48.
A method for the study of thermally induced vibrations of viscoelastic shallow shells of arbitrary shaped plane-form is proposed. It is shown that the time behaviour can be found by assuming a normal mode expansion in tems of the eigenfunctions of the associated elastic shallow shell problem and the deflection is obtained with the aid of the correspondence principle. The response of a shallow shell with rectangular as well as elliptical base to the sudden application of a temperature distribution on the surface of the shell is discussed. For rapidly applied heat inputs, an approximate analysis for its rapid estimation is also presented. All details are illustrated by graphs. 相似文献
49.
Mandira Sinha H. Majumdar P. Basu Subinit Roy R. Bhattacharya M. Biswas M. K. Pradhan R. Palit I. Mazumdar S. Kailas 《The European Physical Journal A - Hadrons and Nuclei》2010,44(3):403-410
Fusion excitation functions are measured for the system 6Li + 28Si using the characteristic $ \gamma$ -ray method, encompassing both the sub-barrier and above-barrier regions, viz, E lab = 7-24 MeV. Two separate experiments were performed, one for the above-barrier region ( E lab = 11-24 MeV) and another for the below-barrier region ( E lab = 7-10 MeV). The results were compared with our previously measured fusion cross-section for the 7Li + 28Si system. We observed the enhancement of the fusion cross-section at sub-barrier regions for both 6Li and 7Li , but the yield was substantially larger for 6Li . However, for well-above-barrier regions, a similar type of suppression was identified for both the systems. 相似文献
50.
The branching ratio for B
s
→ ℓ+ℓ−
γ mode is of the same order as B
s
→ ℓ+ℓ−, since there is no helicity suppression in the 3-body decay mode. New Physics beyond Standard Model may affect these rates
favourably for experimental observation at LHC and simultaneous measurements of the modes B
s
→ μ+μ− and B
s
→ μ+μ−
γ at LHC experiment will indicate the basic nature of the interaction at play. A simulation study has been performed to evaluate
the potential of CMS detector to observe the more difficult mode of B
s
→ μ+μ−γ. An upper limit of 2.08 × 10−7 on the branching ratio is expected to be achieved corresponding to an integrated luminosity of 10 fb−1. 相似文献