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41.
Pulsed nuclear magnetic resonance studies have been carried out on bone marrow of normal human subjects and patients with leukemia: chronic myeloid leukemia (CML) and acute myeloid leukemia (AML). It was observed that the proton spin-lattice relaxation time (T1) value was discriminatory in the normal and leukemic cases with a statistical significance of (p < 0.01). Ouabain treatment of cells did not show any perceptible change of T1 value when compared with the nontreated cells, indicating that the concomitant cation effluxes do not affect spin-lattice relaxation time. The water contents of normal, leukemic, and ouabain treated cells were in the range 60%–80%. Higher Fe levels were encountered in the normal than the leukemic samples, while levels of Zn, Cu, Mn, Co, and Ni were elevated in the leukemic samples compared with the normals. Despite the T1 differences observed, the multiparameter studies do not uniquely pinpoint factors responsible for the elevation of T1 in the malignant state.  相似文献   
42.
A spectrophotometric investigation of the reaction between MeO42? (Me?Mo, W) and gaseous H2Se leading to the identification of the unknown monoselenoanions of molybdenum(VI) and tungsten(VI) is reported. The electronic spectra agree well with the theoretically predicted ones. Further a comparative study of the spectra of different seleno- and thio-anions was made. The first band in the electronic spectra of MoO3Se2? and WO3Se2? is due to the Se → metal charge transfer transition.  相似文献   
43.
Resonance Raman scattering of MoS42? was studied in aqueous solution by irradiating its strong 4700 Å absorption band with five different lines of an Ar+ laser. The vibrational structure of the resonance spectra is discussed. Cross sections and quantum yields for the total scattered radiation were determined using NO3? as an internal standard.  相似文献   
44.
The reaction of MO (M = V, Re) with H2S investigated by spectrophotometry, indicated the existence of two new thioanions VO2S and ReOS. Their spectra are compared with known relationships in those of the thioanions of molybdenum and tungsten. A proposal for the electronic spectrum of VO3S3? is given.  相似文献   
45.
46.
M R Bhiday  U Gupta  M Ranade  S Rao 《Pramana》1973,1(5):235-242
An attempt is made, to obtain mathematical relations correlating the volume and surface effects of the dielectric to those of the electrical impedance of the dielectric system exhibited in the presence of a quasistatic sinusoidal electrical field. A new experiment is described to differentiate clearly the two types of polarizations in an electret.  相似文献   
47.
Diastereoselective liquid-phase hydrogenation of a series of monosubstituted indan substrates was studied on supported rhodium catalysts. Predominantly the cis-cis diastereomer, obtained by hydrogenation from the diastereoface opposite the substituent at the stereogenic center, and the cis-trans diastereomer, obtained by hydrogenation from the diastereoface on the same side as the substituent, were formed. The diastereoselectivity depends on the balance between steric repulsion and electronic attraction of the substituent with the surface of the catalyst. For alkoxy and carboxyl groups (acid, methyl ester, and amide), the steric repulsion dominated and the cis-cis diastereomer was obtained with moderately high selectivity. The diastereoselectivity obtained in the hydrogenation was influenced by the addition of bases to the reaction mixture. Addition of triethylamine caused a small increase in the selectivity to the cis-cis diastereomer in some substrates, whereas the addition of NaOH significantly increased the selectivity toward the cis-trans isomer in all substrates.  相似文献   
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