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1.
Arterial wall thickening may be quantitatively assessed by measuring the intima-media thickness (IMT) with high resolution ultrasound. Previous studies have shown a good inter/intraobserver variability of IMT measurements in the common carotid. In this study we evaluated the inter/intraobserver variability of IMT measurements in 10 randomly selected asymptomatic subjects (age 55.4 +/- 6). Two carotids and two femorals were studied in each subject. IMT for each patient was the average of five IMT measurements at the artery bifurcation. Three observers repeated the scanning and the measurements twice with no knowledge of the previous readings. The between observer coefficient of variation (CV) was 8.45%; the intraobserver CV (mean of carotids and femorals) varied from 4.4 to 5.1% for the three observers who measured IMT three times. The mean absolute difference between the first and the third measurement was 0.0738 mm. In conclusion IMT measurement variability is mostly due to differences between observers. The intraobserver variability is very small. IMT measurements at the carotid and femoral bifurcations have a low variability and are a good expression of atherosclerosis as they consider early lesions at the bifurcation level which may not be observed in the common carotid. 相似文献
2.
E Asakura T Hanamura A Umemura K Yada T Yamauchi T Tanabe 《Canadian Metallurgical Quarterly》1996,195(3):300-313
M-CSF is a macrophage-lineage-specific growth factor that causes proliferation and differentiation of progenitor cells in the bone marrow. To investigate the effects of M-CSF on more matured cells, human monocytes were cultured in the presence or absence of M-CSF for 6 days. Addition of M-CSF at more than 10(2) U/ml resulted in higher viability and caused morphological differentiation to large macrophage-like cells. LPS-induced mediator production was also compared between M-CSF-treated and control cell. Monocytes were incubated with or without M-CSF for 3 days, and were stimulated with 1 microgram/ml of LPS for 2 days. IL-1 beta was not detected in the both culture supernatants, and PGE2 production was not influenced by M-CSF. However, amounts of G-CSF, GM-CSF, IL-6, and TNF-alpha produced in response to 1 microgram/ml of LPS were 1.5 to 2 times greater from monocytes treated with 10(4) U/ml of M-CSF than from control cells. The priming effect of M-CSF on LPS-induced cytokine production was found to require 3-day preincubation, and reached a maximum at the concentration of 10(4) U/ml. M-CSF-treated cells responded to a 10 times lower concentration of LPS than control cells in terms of cytokine production. M-CSF was also shown by flowcytometric analysis to influence the expression of CD14, a receptor for LPS, which might render monocytes more sensitive to LPS. 相似文献
3.
Hideyuki Azegami Liren Zhou Kimihiro Umemura Naoya Kondo 《Structural and Multidisciplinary Optimization》2013,48(1):115-125
This paper presents a numerical solution for shape optimization problems for link mechanisms, such as a piston-crank mechanism. The dynamic behavior of a link mechanism is described by a differential-algebraic equation (DAE) system consisting of motion equations for each single body and constraints of linkages and rigid motions. In a shape optimization problem, the objective function to maximize is constructed from the external work done by a given external force, which agrees with the kinetic energy of the link mechanism, for an assigned time interval, and the total volume of all the links forms the constraint function. The Fréchet derivatives of these cost functions with respect to the domain variation, which we call the shape derivatives of these cost functions, are evaluated theoretically. A scheme to solve the shape optimization problem is presented using the H 1 gradient method (the traction method) proposed by the authors as a reshaping algorithm, since it retains the smoothness of the boundary. A numerical example shows that reasonable shapes for each link such that mobility of the link mechanism is improved are obtained by this approach. 相似文献
4.
Masatsune Kato Takaaki Aoki Takashi Noji Yasuhiro Ono Yoji Koike Tomoyuki Hikita Yoshitami Saito 《Journal of Superconductivity》1994,7(1):37-38
We have investigated the relation between the crystal structure and superconductivity in La1.9Bi0.1CuO4+
, in which the phase separation observed in La2CuO4+
is suppressed. A phase diagram in theT– plane is given for La1.9Bi0.1CuO4+
with excess oxygen. For very small values, the crystal structure is orthorhombic, and an orthorhombic-tetragonal phase transition occurs markedly at 0.03 in the measured temperature range between 13 and 293 K. Superconductivity is observed in the range of 0.04<<0.11. This is clear evidence thathigh-T
c
superconductivity also appears in the tetragonal phase. 相似文献
5.
Takashi Noji Yoji Koike Hideo Iwasaki Masatsune Kato Norio Kobayashi Yoshitami Saito 《Journal of Superconductivity and Novel Magnetism》1996,9(1):65-71
Anisotropie properties of the single crystal Pb2Sr2Ho0.5Ca0.5Cu3O8 have been investigated by measuring the electrical resistivity in theab-planeρ ab (H, θ,T), which depends on the angleθ between theab-plane and the magnetic-field direction, in various constant fieldsH perpendicular to the current direction. All the angle-dependent values ofρ ab (H, θ,T) at a constant temperature are scaled to be on one curve as a function of reduced field. The anisotropic parameter γ≡(m c * /m ab * )1/2 is estimated as 12–13, which is larger than that of YBa2Cu3O7 and much smaller than that of Bi2Sr2CaCu2O8. It has been concluded that the anisotropy does not always depend on the thickness of the blocking layer but seems to depend on the overlap of the electronic wave functions along thec-axis. Anisotropy in the pinning potential has also been discussed from the resistive tail in the temperature dependence ofρ ab (H,θ,T). 相似文献
6.
Y Ikeda Y Fujii M Umemura T Hatakeyama M Morita M Yamazaki 《Canadian Metallurgical Quarterly》1996,746(2):255-260
We have recently chosen to undertake a comprehensive evaluation of the modulation of gene expression by oxidative stress, using mRNA as a marker. Our model system is HA-1 hamster fibroblasts, using conditions under which we observe an adaptive response. Under these conditions, the HA-1 cells respond to a minimally toxic "pretreatment" dose of hydrogen peroxide by synthesizing RNAs and proteins that protect them against subsequent exposure to a highly cytotoxic concentration of hydrogen peroxide. Using the differential display technique to screen for modulated RNAs, we have recently reported an RNA species, adapt15/gadd7, whose steady-state level is significantly induced by a pretreatment dose of hydrogen peroxide (D. R. Crawford, G. P. Schools, S. L. Salmon, and K. J. A. Davies (1996) Arch. Biochem. Biophys. 325, 256-264). Here we report a second induced mRNA, designated adapt33. Two homologous adapt33 mRNAs were revealed by Northern blot hybridization. Both of these species were inducible by hydrogen peroxide, and they were sized at 1.46 and 0.99 kb. These inductions appeared to be dependent upon calcium, occurred as early as 90 min, and were maximal at 5 h. Cell fractionation revealed that a significant proportion of adapt33 RNA is associated with active translation. adapt33 is a novel sequence, as determined by cloning, sequencing, and GenBank analysis. adapt33 represents a new oxidant-inducible RNA and marker of cellular oxidative stress and a potential aid in the study, detection, and possible therapy of oxidant-related disorders. 相似文献
7.
这是一个在商业公园、港口和机场之间开发的项目,要求不能违背大加那利群岛的地理特质。我们的目标是提高这些本地条件,注入明确的城市规划和景观规划方案。我们计划建立3个超级区域网络:东西向的地景河床 相似文献
8.
H Idogawa A Imamura K Matsuo K Yoshitake T Umemura M Ohashi 《Canadian Metallurgical Quarterly》1998,79(2):93-104
In recent years, states have increasingly turned to managed care arrangements for financing and delivering health services to Medicaid beneficiaries. In 1996, approximately 40% of all Medicaid recipients were enrolled in some form of managed care. The rapid escalation of managed care in this population has been fueled by states' desire to slow the growth of Medicaid expenditures and by the trend toward managed care enrollment in the private health insurance industry. The effect of managed care on cost containment in the Medicaid program may be limited, however, because 85% to 90% of Medicaid managed care enrollees are women of childbearing age and children, who together account for 69% of Medicaid recipients, but only 26% of program costs. Nonetheless, the increase in managed care enrollment in this population may have a profound impact on health service delivery and health outcomes for U.S. children, approximately 20% of whom received health benefits through the Medicaid program in 1995. In the future, the proportion of Medicaid-eligible children enrolled in managed care will likely increase as a result of recent legislation that relaxed the requirement that states seek federal approval prior to mandating managed care enrollment for Medicaid beneficiaries. More states are relying on fully capitated arrangements as the preferred type of managed care for Medicaid recipients, despite the relative lack of experience many of these plans have in serving this low-income population. Moreover, managed care organizations have few incentives to enroll chronically or disabled children with higher-than-average expected costs. Without mechanisms in place that adequately adjust capitated rates to account for these higher-cost enrollees, managed care organizations may lose money, and children with the greatest health care needs may be underserved. As mandatory managed care enrollment for Medicaid recipients increases nationwide, states should carefully monitor changes in program costs and quality as well as implications for the delivery of pediatric health services and health outcomes. 相似文献
9.
M Sawada CH Park H Kondo T Morita A Shimada I Yamane T Umemura 《Canadian Metallurgical Quarterly》1998,60(7):853-854
Prevalence of antibody to Neospora caninum (NC) in Japanese dogs were examined. The antibody was positive in 15 of 48 dogs (31.3%) reared in the dairy farms that had case of the abortions due to NC infection or had the cattle seropositive to NC, whereas the prevalence was 7.1% (14 of 198 dogs) among the dogs kept in urban areas. In one dog breeder, all 17 Shetland sheepdogs older than 7 months were seropositive, and one pup was diagnosed as neosporosis 2 months before the first serological examination. The antibody titers of the dogs kept at this breeder were almost unchanged for 1.5 years. Serological evidence of the dogs in the dairy farms and urban areas indicates the transmission of NC between dogs and cattle. Also serological results of the dogs in one breeder may suggest the potential horizontal transmission among dogs. 相似文献
10.
The effect was studied of the pH of the amino-carbonyl reaction on the photodegradation of model melanoidins. Nondialyzable model melanoidins were prepared from glucose and lysine with or without initial pH control to 7.0.: 2 mol/l phosphate buffer (buffer-melanoidin) and pH adjustment at the reaction start with NaHCO3 (NaHCO3-melanoidin). Melanoidin was also prepared from glucose and the lysine-Cu2+complex to investigate the difference of complexes between melanoidin and Cu2+ (Cu2+-melanoidin). Each melanoidin solution was irradiated with a Xe or tungsten-halogen lamp under dissolved oxygen or by the continuous supply of oxygen in a Cu2+/O2 or ascorbic acid/Cu2+/O2 system. The effects of the concentrations of Cu2+ and melanoidin, reaction pH value, and metal ion species on the decolorization rate in the Cu2+/O2 system were investigated. The most effective factor for decolorization was found to be the melanoidin concentration. The decolorization rate was negligible when 14 g/l of Cu2+-melanoidin was photodegraded in the ascorbic acid/Cu2+/O2 system under dissolved oxygen, although depolymerization was observed. Photodegradation of NaHCO3-melanoidins in the Cu2+/O2 system by the continuous supply of oxygen resulted in an increased decolorization rate, decreased molecular mass, production of low-molecular-weight compounds, release of free lysine, and pI change. The buffer- and Cu2+-melanoidins did not show changes in chemical characteristics similar to those of the NaHCO3-melanoidin. 相似文献