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991.
992.
Irradiation of thymus with doses of 0.5 to 10 Gy and gonads with 10 Gy does not influence the growth of the tumor transplanted 10 days after irradiation and accelerates the growth of the tumor transplanted 11-12 months after exposure. Irradiation of hypophysis and hypothalamus with doses of 1 and 10 Gy accelerates the growth of the tumor transplanted 10 days and 11-12 months after exposure. In the latter case the effect was more pronounced. When thymus, hypothalamus and hypophysis were exposed simultaneously the effect was analogous to that observed after isolated exposure of hypothalamus/hypophysis but somewhat more pronounced. Irradiation of hypothalamus/hypophysis caused earlier and severer changes in the anti-tumor resistance than the exposure of thymus and gonads did.  相似文献   
993.
994.
995.
To determine the possibility of discriminating multi-sources in the brain by 3D vector magnetic field measurement of a magnetoencephalogram (MEG), measurements were made of magnetic fields produced by two current dipoles implanted in a spherical head model. The 3D vector magnetic field measurements were made by using a 3D second-order gradiometer connected to three rf-SQUIDs, which can detect magnetic field components perpendicular to and tangential to the scalp. The MEG distribution measuring the magnetic field perpendicular to the scalp was not helpful in estimating the location and number of sources because of the lack of a dipole pattern. By referring to the MEG distribution measuring the magnetic field distribution tangential to the scalp, however, two current sources could be clearly discriminated in a spherical head model. It was found that this MEG distribution measuring tangential to the scalp could provide information on new constraint conditions for the calculation of inverse problems with multi-sources. These results were also confirmed by measurement of the mixed somatosensory evoked fields elicited by simultaneous electric stimulation to the median nerve and the thumb.  相似文献   
996.
RATIONALE AND OBJECTIVES: The standard binormal model is the most commonly used model for fitting receiver operating characteristic rating data; however, it sometimes produces inappropriate fits that cross the chance line with degenerate data sets. The authors proposed and evaluated a proper constant-shape bigamma model to handle binormal degeneracy. METHODS: Monte Carlo samples were generated from both a standard binormal population model and a proper constant-shape bigamma model in a series of Monte Carlo studies. RESULTS: The results confirm that the standard binormal model is robust in large samples with no degenerate data sets and that the standard binormal model is not robust in small samples because of degenerate data sets. CONCLUSION: A proper constant-shape bigamma model seems to solve the problem of degeneracy without inappropriate chance line crossings. The bigamma fitting model outperformed the standard binormal fitting model in small samples and gave similar results in large samples.  相似文献   
997.
998.
The effects of three moisture levels (0, 10, and 20% added water) and three processing temperatures (115.6, 121.1, and 126.7 C) on texture and collagen solubilization of fowl meat gels were examined. Meat gels were formulated from spent fowl breast meat that were cooked in water (71.1 C internal temperature) prior to heat processing. The water-cooked gels were heat processed at the three temperatures to an F0 value of 6.0 (Z value = 10 C). The addition of 20% water resulted in a reduction of the soluble collagen compared to the 10% water-added treatment. The lowest processing temperature increased the soluble collagen compared to the highest processing temperature. Shear stress and hardness decreased as the amount of added water was increased; and the lowest processing temperature resulted in the lowest hardness values. The increase in soluble collagen parallels the decrease in hardness in the samples processed at the lowest temperature. Because each sample was processed to equivalent F values, the lowest processing temperature had the longest exposure time (26 min at 115.6 C, 12 min at 121.1 C, and 6 min at 126.7 C). The longer exposure to moist heat allowed for greater collagen solubilization and lower hardness values. The 0% added-water treatment had the highest yield from before and after heat processing. However the 10% water-added samples had the greatest overall water retention when each treatment was placed on an equal level of initial water content. Furthermore, the highest processing temperature (shortest processing time) resulted in the greatest yield and moisture retention compared to the other processing temperatures.  相似文献   
999.
The effect of subinhibitory concentrations of amikacin on Proteus mirabilis motility and adherence to human uroepithelial and to HeLa cells was compared with that of gentamicin. In addition, the effect of both antibiotics on cell surface hydrophobicity was also examined. Exposure of bacterial cells in the logarithmic phase to one fourth of amikacin or gentamicin at one fourth of their respective minimal inhibitory concentrations causes the inhibition of swarming and motility of Proteus strains. Amikacin significantly reduced adhesion of Proteus strains to human uroepithelial cells and gentamicin exerts the same effect to a lesser extent. Such inhibitory concentrations of amikacin or gentamicin had no significant effect on the attachment ability of these strains to HeLa cells compared to the nontreated cells. Treatment of the bacterial cells with amikacin or gentamicin changed significantly the cell surface hydrophobicity towards the hydrophilic state compared to nontreated cells, and it was found to be strain dependent. Since motility and attachment ability are considered as pathogenic traits, these data indicate the impact of amikacin on the virulence factors especially in urinary tract infections with Proteus strains.  相似文献   
1000.
An affinity purified antibody specific for midkine (MK) stained senile plaques in the brain of Alzheimer disease (AD) patients. After formic acid treatment, plaque staining was dramatically enhanced, and almost all beta-amyloid protein (BAP) deposits were also immunoreactive for MK. MK-immunoreactivity was not observed in normal cellular components nor in other pathological lesions including tangles in AD brain. Control brain sections were not immunoreactive for MK. The presence of MK in AD brain but not in control brain was confirmed by Western blotting. MK appears to be involved in the pathological process leading to senile plaque formation.  相似文献   
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