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161.
Two experiments were conducted to investigate the effects of varying levels of pantothenic acid on the efficiency of energy utilization and changes in body composition of the growing chick. The results indicate that a pantothenic acid deficiency does not interfere with the chick's ability to obtain metabolizable energy from the diet. The data do show that the efficiency of energy utilization and body composition were markedly affected when chicks were fed diets deficient in pantothenic acid. In both experiments, protein, fat and energy stores were significantly reduced when pantothenic acid-deficient diets were fed. Increased estimates of heat increment per gram of diet were observed when levels of pantothenic acid below the N.R.C. (1971) recommended level of 10 mg. per kg of diet were fed. 相似文献
162.
The design of a two-dimensional (2D) magnetic field search coil system based on the phase detection principle is described. The system was developed to record horizontal and vertical eye and head movements of small, unrestrained laboratory animals. It is also applicable for measuring three-dimensional (3D) eye and head movements in primates and man. The output is linear over 355 degrees in the horizontal plane and over +/- 60 degrees in the vertical direction. The procedure of recording 3D eye and head movements is discussed. 相似文献
163.
Plasma fractions and plasma dialysate from 2,4-dinitrochlorobenzene- and tuberculin-sensitive guinea pigs that had been treated with either antilymphocytic serum or normal control serum were analyzed for their ability to transfer lymphocyte transformation, passive cutaneous anaphylaxis, and macrophage migration inhibition, as well as delayed hypersensitivity in vivo. Antilymphocytic serum caused rapid release of material, which has characteristics of transfer factor, into the plasma. It was dialyzable, migrated electrophoretically with the alpha globulins and albumin, possessed a 280/260 (nm) optical density ratio of 0.7, and caused in vitro lymphocyte transformation in the presence of the specific antigen. Passive cutaneous anaphylaxis antibodies were also present in the plasma of sensitive animals, but they were isolated in electrophoretic or dialysis fractions separate from those containing transfer activity. 相似文献
164.
Prof. Dr.-Ing. M. Kasper Dipl.-Ing. A. Kost 《Electrical Engineering (Archiv fur Elektrotechnik)》1987,70(5):333-339
Übersicht Für Leitungen unterschiedlicher Form der einzelnen Leiter-Querschnitte werden in Abhängigkeit von Leiterabstand und Frequenz die Impedanzen und insbesondere die Verluste ermittelt, auch die Stromdichteverteilung wird dargestellt. Die Berechnung erfolgt mit der Methode der finiten Elemente.
Skin- and proximity-effect in transmission lines of different cross sections
Contents Impedances and especially losses are calculated for transmission lines of different cross section of the particular conductors as a function of their distance and the frequency. The distribution of the current density is obtained. The finite-element-method is applied.相似文献
165.
We contrived a new separation system using a stirred cell charged with uncoupled microsphere similar to the chromatographic separation. Microspheres, carboxylated PS/PMAA and sulfonated PS/PNaSS, were prepared by emulsifier-free emulsion polymerization. To complement the submicron size weakness and the absence of ligands, we employed the latex form, the dispersion of microsphere, and took advantage of interaction relationships between proteins and microspheres. Adsorption isotherm is contemplated to investigate continuous separation behaviours of serum proteins. Selectivity of separation is in the following order: PS/PNaSS-2.0 (high sulfonated) < PS/PNaSS-0.3 (low sulfonated) < PS/PMAA-0.5 (low carboxylated). Unlike previous works on batch separation, not only the adsorbed amount in equilibrium (Cm), but also adsorption coefficient (K), played an important role in continuous separation. Functional groups (carboxyl and sulfonate), induced from the co-monomer, also affected the adsorption behaviours. 相似文献
166.
VA Kickhoefer KS Rajavel GL Scheffer WS Dalton RJ Scheper LH Rome 《Canadian Metallurgical Quarterly》1998,273(15):8971-8974
Vaults are 13-MDa ribonucleoprotein particles composed largely of a 104-kDa protein, termed major vault protein or MVP, and a small vault RNA, vRNA. While MVP levels have been found to increase up to 15-fold in non-P-glycoprotein multidrug-resistant cell lines, the levels of vault particles have not been investigated. As both the function of vault particles and the mechanism of drug resistance in non-P-glycoprotein cells are unknown, we decided to determine whether vault synthesis was coupled to MDR. By cloning the human gene for vRNA and careful quantitation of the MVP and vRNA levels in MDR cells, we find that vRNA is in considerable excess to MVP. Sedimentation measurements of vault particles in multidrug resistance cells have indeed revealed up to a 15-fold increase in vault synthesis, coupled with a comparable shift of associated vRNA, demonstrating that vault formation is limited by expression of MVP or the minor vault proteins. The observation that vault synthesis is linked directly to multidrug resistance supports a direct role for vaults in drug resistance. 相似文献
167.
Carbon nitride thin films deposited using dc unbalanced magnetron sputtering system have been analyzed by X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT1R) and Raman spectroscopy. The XPS data show that N1s binding states depend on substrate temperature Ts, in which the peak at 400.0 eV increases with Ts, whereas the peak at 398.3 eV decreases with Ts slightly On the basis of XPS, FT1R and Raman spectra, the assignment of N1s electron binding energies was made. The peak at 400.0 eV is attributed to N atoms bonded to sp2 coordinated C atoms. The peak at 398.3 eV is attributed to N atoms bonded to sp3 coordinated C atoms as well as N C bonds. 相似文献
168.
Sensitivities at 5.5 deg off-fovea from the aphakic observer superimposed on orange, purple and blue fields were obtained to estimate short-, middle- and long-wavelength cone spectra respectively. The middle-wavelength mechanism had a visible wavelength maximum resembling a nomogram plus an UV sensitivity fitting a cis-peak. The short (and, to a lesser extent, the long) wavelength cone sensitivities are higher in the UV than expected. 相似文献
169.
A series of five innovative experiments conducted by Wirth et al. which examined the effect of various complementary healing interventions on the reepithelialization rate of full thickness human dermal wounds was assessed as to specific methodological and related factors. The treatment interventions utilized in the series included experimental derivatives of the Therapeutic Touch (TT), Reiki, LeShan, and Intercessory Prayer techniques. The results of the series indicated statistical significance for the initial two experiments and nonsignificance or reverse significance for the remaining three studies. This review article examines the methodological designs of the series of studies, along with the TT practitioners' phenomenologically based journal reports, to provide potential contributing correlative factors for the differential results obtained. These factors include: (1) methodological design restrictions, (2) a transference/inhibitory effect (3) the influence of experimental assistants, (4) healer visualization /imagery techniques, (5) variations in subject populations, and (6) a potential cancellation effect. While the placebo controlled double-blind methodological designs used in the series were as stringent as those used in other fields of scientific inquiry, the overall results of the experiments were inconclusive in establishing the efficacy of the treatment interventions for accelerating the rate of reepithelialization of full thickness dermal wounds. 相似文献
170.