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51.
T Smith AK Hewson CI Kingsley JP Leonard ML Cuzner 《Canadian Metallurgical Quarterly》1997,150(6):1909-1917
Acute, monophasic experimental allergic encephalomyelitis (EAE) in the Lewis rat shows pathological similarities to the human disease multiple sclerosis (MS). Rats that recover from EAE are essentially resistant to disease reinduction, unlike MS in which relapses are frequently associated with common bacterial and viral infections. As macrophage-derived interleukin (IL)-12 is a critical component of innate resistance to bacterial infection and appears to directly activate encephalitogenic T cells in vivo, the ability of this cytokine to reinduce paralysis in EAE was examined. Paralytic disease was exacerbated by intraperitoneal IL-12 administration and could be reinduced up to 1 week after recovery from the primary clinical episode. Concomitant with worsening of initial clinical signs and relapse was an increase in the ratio of macrophages to T cells in brain stem perivascular cuffs and the expression of inducible nitric oxide synthase in cells with both macrophage and microglial morphology. These findings suggest that IL-12 may contribute to macrophage-mediated disease exacerbation and relapse in patients with MS. 相似文献
52.
The suppression of the superconductivity by praseodymium in La1−x
Pr
x
CaBaCu3O7 may be explained in terms of the difference in the electronic or crystal structure between these compounds. Three compositions
with x=0.0, 0.5, 1.0 were, therefore, investigated by X-ray diffraction in order to determine the unit-cell dimensions at room temperature
as well as at lower temperatures down to 5 K. The results showed no considerable changes in the orthorhombic unit-cell dimensions
on decreasing the temperature to 5 K. Unit-cell volumes at low temperatures were 0.99 of the room temperature values. The
intensity sequence of reflections in the diffraction pattern was the same for all samples throughout the range of temperature
studied. 相似文献
53.
54.
S. J. C. Irvine A. Stafford M. U. Ahmed A. Brown H. Kheyrandish 《Journal of Electronic Materials》1997,26(6):723-727
The first detailed comparison has been made of the metalorganic vapor phase epitaxy growth rates of CdTe, ZnTe, and ZnSe,
measured in situ with laser reflectometry. The comparison also includes the photo-assisted growth with visible radiation from
an argon ion laser. Using a standard Group II precursor (DMCd or DMZn.TEN) partial pressure of 1.5 × 10−4 atm, VI/II ratio of 1 and DIPM (M = Te, Se) the maximum growth rates are in the region of 10 to 15 AU/ s. Decrease in growth
rates of ZnTe at higher temperatures or higher laser powers have been attributed to the desorption from the substrate of unreacted
Te precursor. The behavior of DTBSe is quite different from DIPSe for both pyrolytic and photo-assisted growth. The maximum
growth rate is around 1 AU/ s with very little photo-enhancement, except at 300°C. Secondary ion mass spectroscopy analysis
of hydrogen concentration in the ZnSe layers shows high concentrations, up to 5.9 × 1019 atoms cm−3 for DTBSe grown ZnSe under pyrolytic conditions. These results show that the growth kinetics play an important part in the
incorporation of hydrogen and passivation of acceptor doped material. 相似文献
55.
WC Miller KE Eggert JP Wallace AK Lindeman C Jastremski 《Canadian Metallurgical Quarterly》1993,14(7):401-405
There is little evidence concerning the effectiveness of self-help materials for weight control. The purpose of this research was to evaluate a self-help weight-loss program. Obese (body fat > or = 25.0%, range = 25.0-48.6%, mean +/- SEM = 36.5 +/- 1.3%) men (n = 14) and women (n = 21) were given a workbook detailing a behavior modification approach to weight loss that emphasizes self-monitoring of diet and exercise behaviors, and then sent home for 6 months to learn how to lose weight on their own. A group of 9 controls (CONT) who did not get a workbook were used for comparison. ANOVA showed that the experimental group (EXP) lost 8.1 +/- 0.9 (mean +/- SEM) kg body weight, 6.4 +/- 0.8 kg fat, and 3.9 +/- 0.6% body fat; all significant over time (p < 0.001) and different from the CONT (p < 0.0001) who showed no change in these variables. The EXP also reduced their fat intake (% of joules) from 36.1 +/- 1.0% to 27.9 +/- 1.3% (p < 0.0001), increased their carbohydrate intake from 45.7 +/- 1.2% to 50.0 +/- 1.7% (p < 0.007) and their protein intake from 16.3 +/- 0.05% to 20.7 +/- 0.7% (0 < 0.03), all of which were significantly different (p < 0.03) than the CONT who did not change. Dietary fiber increased in the EXP from 19.8 +/- 1.4 to 27.3 +/- 2.2 g/d (p < 0.001) even with a significant reduction in energy intake (11.3 +/- 0.6 vs. 8.9 +/- 0.5 Mj/d; p < 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
56.
Isolation of Shigella dysenteriae serotypes 11, 12, and 13 from patients with diarrhea in Bangladesh
M Ansaruzzaman AK Kibriya AK Mitra RB Sack MJ Albert 《Canadian Metallurgical Quarterly》1993,31(5):1392-1393
Nine isolates of bacteria biochemically resembling Shigella dysenteriae but not belonging to the 10 recognized serotypes were isolated from patients with diarrhea in Bangladesh. Further studies suggested that two, one, and six isolates belonged to the recently recognized S. dysenteriae serotypes 11, 12, and 13, respectively. 相似文献
57.
58.
59.
The electrical properties of CdTe thin film have been studied and discussed, including, the conduction mechanism, and the effect of temperature and indium doping on the current passing through the CdTe film and hence on the film conductivity. It is observed that the CdTe film is of the modified Poole–Frenkel conduction mechanism and the resistivity of the film can be lowered by more than one order of magnitude due to indium doping. 相似文献
60.
In this article, a new extension of affine arithmetic is introduced. This technique is based on a quadratic form named general quadratic form. We focus here on the computation of reliable bounds of a function over a hypercube by using this new tool. Some properties
of first quadratic functions and then polynomial ones are reported. In order to show the efficiency of such a method, ten
polynomial global optimization problems are presented and solved by using an interval branch-and-bound based algorithm.
The work of the first author was also supported by the Laboratoire de Mathématiques Appliquées CNRS–FRE 2570, Université de
Pau et des Pays de l'Adour, France, and by the Laboratoire d'Electrotechnique et d'Electronique Industrielle CNRS–UMR5828,
Group EM3, INPT–ENSEEIHT. 相似文献