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61.
M Motomura T Hoshino G Tomonaga S Morioka Y Shimono 《Canadian Metallurgical Quarterly》1977,41(9):983-989
Thirteen patients with aortic regurgitation (AR) and 13 with mitral regurgitation (MR) were compared quantitatively from the standpoint of their vector-cardiograms (VCG). Vectorcardiographic parameters were also compared with left ventricular angiographic parameters. The QR time interval was longer and the magnitude of the spatial maximum QRS vector was larger in the AR group, but these differences were thought to be attributed to the differences in length of the left ventricular long axis and the left ventricular end diastolic volume (LVEDV). In the AR group, the ratio of the width to the long axis of the QRS loop in the horizontal plane correlated well with the length of the left ventricular long axis and the angle made by the axis from the middle of the aortic valve to the left ventricular apex and the horizontal axis in the lateral view of the angiogram. In the MR group, these correlations were poor. 相似文献
62.
J Guzowski MM Paparella K Nageswara T Hoshino 《Canadian Metallurgical Quarterly》1976,86(8):1141-1146
Meningiomas should be considered in the differential diagnosis of otologic tumors arising from the middle ear and mastoid. It is generally recognized that meningiomas may invade the temporal bone via direct extension from the intracranial space (secondary). It is not generally recognized that meningiomas can develop initially in the middle ear cleft (primary). Representative cases of primary and secondary meningiomas of the temporal bone are described and clinical aspects of diagnosis surgical management are discussed. In order to assess the pathogenesis of meningiomas of the temporal bone, histological studies were done on 200 temporal bone specimens. In certain specimens, ectopic arachnoid granulations, from which primary meningiomas may originate, were identified and described, according to location. One specimen was most unusual in that it contained ectopic glial as well as arachnoidal tissue. 相似文献
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The following well-known equation permits the ready determination of M n from a single osmotic pressure measurement at a known concentration, if the second virial coefficient is previously given: On this basis, the one-point method was investigated to determine the number-average molecular weight. It was found that this method was applicable to commercial polymers. However, in this application, the dependence of Γ2 on molecular weight distribution has to be kept in mind. 相似文献
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67.
An enzyme which participated in the oxidation of hydroxylamine to nitrite from was partially purified Alcaligenes faecalis, and some of its properties were studied. The enzyme oxidized aerobically pyruvic oxime to nitrite in the presence of hydroxylamine or ascorbate. As molecular oxygen equimolar to nitrite formed was consumed in the enzymatic oxidation of pyruvic oxime to nitrite, the enzyme was thought to be a dioxygenase. It was an iron protein, and a reducing reagent was required to keep the iron in the ferrous state for the action of the enzyme. 相似文献
68.
Axial nonuniformities in the carrier density profile of 1.55 μm capped-mesa-buried-heterostructure distributed-feedback (CMBH-DFB) InGaAsP-InP diode lasers are discussed. This is accomplished by directly measuring the spontaneous emission at various locations in the laser optical cavity. The authors observe that the highly asymmetric optical field, inherent in DFB lasers, produces a strong longitudinal nonuniformity in the carrier density. This promotes degradation of the lasing gain margin between the dominant TE Bragg modes, which is verified through measurements of the relative shift of the lasing mode in the stopband. The reduction of gain margin is shown to cause multimode operation in devices with large optical field asymmetries. In devices with modest optical field asymmetries, the reduction of the gain margin saturates, and single mode behavior is maintained. Measurements are consistent in many respects with the predicted consequences of spatial hole burning 相似文献
69.
Masayuki Itagaki Kazuya Hoshino Yuya Nakano Isao Shitanda Kunihiro Watanabe 《Journal of power sources》2010,195(19):6905-7983
Theoretical equations of the Faradaic impedance of the photoelectrode and the counter electrode of dye-sensitized solar cell (DSC) were derived. The Faradaic impedance is the frequency dependent resistance related to the time constants of elementary electrode processes like photoexcitation, electron transfer, charge transfer reaction and diffusion. The typical cell impedance spectrum describes the locus of three semicircles on the Nyquist plane. The locus of three semicircles is generally analyzed by using the equivalent circuit composed of charge transfer resistance (Rct,1) and capacitance (Cdl,1) of counter electrode, charge transfer resistance (Rct,2) and capacitance (Cdl,2) of photoelectrode, the finite diffusion impedance due to the diffusion of I3− on the counter electrode (Zw), and total resistance of the substrate and solution (Rs). The physical meanings of Rct,1 and Rct,2 can be elucidated by the interpretations of Faradaic impedance derived in the present paper. The Rct,1 is represented as the function of the potential-dependent rate constants of I3− reduction and I− oxidation. On the other hand, the Rct,2 is the function of the photoelectrode potential, the surface concentration of I3− and the potential-independent rate constant of the back electron transfer reaction. The theoretical expressions of the current-voltage (I-V) curve of the DSC can be also derived. In the present paper, the relations between the impedance and I-V curve of the DSC are discussed. 相似文献
70.
GFP expression by intracellular gene delivery of GFP-coding fragments using nanocrystal quantum dots
Hoshino A Manabe N Fujioka K Hanada S Yasuhara M Kondo A Yamamoto K 《Nanotechnology》2008,19(49):495102
Gene therapy is an attractive approach to supplement a deficient gene function. Although there has been some success with specific gene delivery using various methods including viral vectors and liposomes, most of these methods have a limited efficiency or also carry a risk for oncogenesis. We herein report that quantum dots (QDs) conjugated with nuclear localizing signal peptides (NLSP) successfully introduced gene-fragments with promoter elements, which promoted the expression of the enhanced green fluorescent protein (eGFP) gene in mammalian cells. The expression of eGFP protein was observed when the QD/gene-construct was added to the culture media. The gene-expression efficiency varied depending on multiple factors around QDs, such as (1) the reading direction of the gene-fragments, (2) the quantity of gene-fragments attached on the surface of the QD-constructs, (3) the surface electronic charges varied according to the structure of the QD/gene-constructs, and (4) the particle size of QD/gene complex varied according to the structure and amounts of gene-fragments. Using this QD/gene-construct system, eGFP protein could be detected 28 days after the gene-introduction whereas the fluorescence of QDs had disappeared. This system therefore provides another method for the intracellular delivery of gene-fragments without using either viral vectors or specific liposomes. 相似文献