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41.
42.
N Furusyo J Hayashi Y Sawayama Y Kawakami Y Kishihara S Kashiwagi 《Canadian Metallurgical Quarterly》1998,59(5):693-698
Serial changes in hepatitis A virus (HAV) and B virus (HBV) markers were determined from 1970 to 1996 in healthy Japanese residents of a rural area of Okinawa, Japan. All 190 serum samples taken in 1970, 791 in 1980, 708 in 1988, and 523 in 1996 from residents 0 to more than 60 years of age were tested for antibody to HAV (anti-HAV), antibody to hepatitis B core antigen (anti-HBc), and hepatitis B surface antigen (HBsAg). The age-adjusted prevalences of anti-HAV and anti-HBc decreased significantly from 83.9% and 74.9%, respectively, in 1970 to 39.7% and 36.6%, respectively, in 1996. In residents < or = 29 years of age, the prevalences of anti-HAV and anti-HBc decreased significantly from 65.3% and 83.8%, respectively, in 1970 to 0.7% and 8.2%, respectively, in 1996. The age-adjusted HBsAg prevalence decreased significantly from 8.2% in 1980 to 4.1% in 1988. These results indicate that exposure to HAV and HBV infections among Okinawa residents less than 29 years of age is decreasing, probably because of improvements in socioeconomic conditions since 1970. Infection with HBV may be eliminated there in the near future. 相似文献
43.
To investigate the mechanism of the vocal cord abductor paralysis (VCAP) in the neurodegenerative diseases, the intrinsic laryngeal muscles (the crycothyroid, the interarytenoid, and the posterior crycoarytenoid muscles) from 41 autopsied cases were histologically examined: 10 cases of amyotrophic lateral sclerosis (ALS), 10 of Parkinson's disease (PD), 9 of multiple system atrophy (MSA), 4 of Machado-Joseph disease (MJD), 4 of progressive supranuclear palsy (PSP), 1 of familial amyloidotic polyneuropathy (FAP), and 3 of cerebrovascular diseases as a control. According to the distribution of the neurogenic changes among above-described three intrinsic laryngeal muscles, three forms were raised: 1. The totally paralytic form showing that all the three muscles developed neurogenic atrophy. This form includes ALS, MJD, and FAP. 2. The posterior muscle-paralytic form showing that only the posterior crycoarytenoid muscle was selectively involved. This form includes MSA. 3. The nonparalytic form showing no morphological abnormalities in any of the intrinsic laryngeal muscles. This type includes PD and PSP. In this nonparalytic form, supranuclear mechanism such as pyramidal or extrapyramidal tract involvement may cause VCAP through the increased laryngeal muscles tone. Considering that VCAP can be seen in any of the above-described forms, our results indicate that the mechanism of VCAP is different among the neurological disorders. 相似文献
44.
H Koga K Hayashi E Taketomi S Matsunaga S Yashiki T Fujiyoshi S Sonoda T Sakou 《Canadian Metallurgical Quarterly》1996,21(4):469-473
STUDY DESIGN: The present study analyzed the restriction fragment length polymorphism patterns of alpha 2(XI) collagen, bone morphogenetic protein-2, alkaline phosphatase, and tumor necrosis factor-alpha genes in patients with ossification of the posterior longitudinal ligament. This study investigates the genetic polymorphism of bone-induced factors in patients with ossification of the posterior longitudinal ligament and compares it with healthy control subjects. OBJECTIVES: To clarify the genetic markers linked to ossification of the posterior longitudinal ligament. SUMMARY OF BACKGROUND DATA: Ossification of the posterior longitudinal ligament is a genetic disease associated with abnormal calcium metabolism involving the posterior longitudinal ligament. Previous genetic studies have not identified the pathologic mechanism of ossification of the posterior longitudinal ligament. Histopathologic studies of ossification of the posterior longitudinal ligament and the animal model, the spinal hyperostotic mouse, have revealed an increase in Type XI collagen and bone morphogenetic protein-2 expression. METHODS: Eighteen Japanese patients with ossification of the posterior longitudinal ligament and 51 healthy, unrelated control subjects were investigated for the restriction fragment length polymorphism patterns of COL11A2, bone morphogenetic protein-2, alkaline phosphatase, and tumor necrosis factor-alpha, genes with various restriction endonucleases. RESULTS: The gene frequencies of COL11A2 obtained with BamHl (10.0 kb fragment) and HindIII (19.0 kb fragment) observed in patients with ossification of the posterior longitudinal ligament were higher compared with control subjects (0.43 and 0.14, respectively). These differences were statistically significant (BamHl P = 0.018; Hindlll P = 0.046). Two new restriction fragment length polymorphism patterns were detected of the bone morphogenetic protein-2 gene with Mspl and Taql and one already known restriction fragment length polymorphism pattern of the tumor necrosis factor-alpha gene with Ncol. However, they were not significantly different from the control subjects. CONCLUSIONS: Seven restriction fragment length polymorphisms of COL11A2 gene were identified. Two of them (BamHl, 10.0/10.0 kb genotype; HindIII, 19.0/19.0 kb genotype) were significantly different in patients with ossification of the posterior longitudinal ligament. 相似文献
45.
Yuma Sano Ryosuke Nonaka Masahiro Baba 《Journal of the Society for Information Display》2012,20(9):539-546
This paper proposes a wide gamut LCD using locally dimmable four‐primary‐color (4PC) LED backlight. Although the color gamut of LCDs has been improved in recent years, it is insufficient to reproduce all the colors in the real world. The objective of this paper is to propose a wide gamut LCD that reproduces all the colors in the real world while keeping the cost increases to a minimum. We evaluated the color gamut reproduced by LEDs of multiple primary colors and selected cyan as the optimal color to be added to the three primary colors to reproduce all the colors in the real world. Therefore, we designed an LED backlight consisting of an additional only‐cyan LED with three‐primary‐color LEDs and developed a prototype LCD with 4PC LED backlight. Furthermore, we developed a local dimming algorithm for the 4PC LED backlight. As a result, we confirmed that the prototype LCD with the 4PC LED backlight is able to cover almost all the colors in the real world and also able to display natural images with highly saturated colors by local dimming. 相似文献
46.
Toshihiro Kasuga Masahiro Yoshida Tomoko Uno Kiichi Nakajima 《Journal of Materials Science》1988,23(6):2255-2258
Bioactive glass-ceramics toughened by tetragonal zirconia polycrystal (TZP) were prepared by hot-pressing mixed powders of the MgO-CaO-P2O5-SiO2 glass and TZP containing 20 to 80% alumina. The bending strength and the fracture toughness of the composite materials were improved compared with those of the material without TZP. These composites showed high bending strengths (400 to 500MPa) and high fracture toughness ( 2.8MPa m1/2). The existence of a crack deflection mechanism was observed by scanning electron microscopy. After soaking in simulated physiological solution at 100 °C, no phase transformation from tetragonal to monoclinic of TZP in the composites and no degradation in bending strength occurred. 相似文献
47.
Rod-shaped BaTiO3 powder particles have been prepared from rod-shaped TiO2 ·nH2O and BaCO3 in molten chloride. The morphology of BaTiO3 particles was studied referring to the effects of the chemical species of the starting titanium compound, amount of chloride, particle size of the titanium compound and reaction conditions, and the preparation condition of rod-shaped BaTiO3 has been determined: i.e., large TiO2 ·nH2O particles were heated at 700°C in molten salt with an equal amount of BaTiO3. This condition was effective in suppressing the formation of BaTiO3 by a solution-precipitation process as well as the deformation of either TiO2 ·nH2O or BaTiO3, which are responsible for the formation of equiaxed BaTiO3 particles. The obtained rod-shaped BaTiO3 particles had a cubic symmetry. Electron diffraction analysis showed that the following topotactic relation is retained; 0 1 0potassium tetratitanate 0 1 0hydrated titania 1 0 0anatase 1 0 0barium titanate 相似文献
48.
Takashi Hayashi Makoto Mihoya Iwao Yamai Hajime Saito Shin-Ichi Hirano 《Journal of Materials Science》1987,22(4):1305-1309
Needle-like or wool-like Al2O3 whiskers can be grown on a substrate by the hydrolysis of aluminium fluoride vapour. Effects of the growth conditions on the morphology of the crystals and growth processes of the whisker were investigated, and the optimum growth condition of whiskers was examined. Adequate vapour pressure conditions of the reactant gases for the growth of the wool-like whisker were found to be
. Aluminium oxyfluoride was assumed to be the most probable intermediate species for the growth of Al2O3 whiskers. A variety of crystal morphologies are also shown and described with respect to the experimental conditions. 相似文献
49.
Fe-30Ni alloy specimens were oxidized for 10–240 min at 433–473 K in pure oxygen at a pressure of 1.33×104 Pa. The thickness of oxide films was measured by a multiple-angle-of-incidence ellipsometer. The kinetics of film growth were found to obey a parabolic rate law. The depth-profiling of oxidized surfaces, performed with simultaneous use of Auger electron spectroscopy (AES) and argon-ion sputter-etching technique, reveals that iron component is selectively oxidized and an iron-depeletion zone is formed in the underlying alloy. The thickness of the iron depletion zone increases with increasing oxidation time or oxidation temperature. During surface oxidation of the alloy, the transport rate of iron component in the film is almost equal to the interdiffusion rate in the underlying alloy, indicating the establishment of a steady state. The values of the interdiffusion coefficient,
, of the underlying alloy estimated from the depth-composition profiles are more than 10 orders of magnitude as large as the values extrapolated from the lattice diffusion data of the corresponding alloy obtained at high temperature. The enormously large values of
may be explained in terms of the vacancy (monovacancy or divacancy)-enhanced lattice diffusion mechanism. 相似文献
50.
The wax esters of sperm whale head oil have been characterized by gas-liquid chromatography on an APOLAR 10C column according
to their carbon number and number of double bonds. The novel technique permits the direct quantitative analysis of saturated
and unsaturated wax esters. 相似文献