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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.
Molecular cloning of a canine metallothionein cDNA 总被引:1,自引:0,他引:1
A canine metallothionein cDNA obtained from the liver of a cadmium-treated beagle was cloned and sequenced. Asn at position 4 conserved among all mammalian metallothionein-1 and metallothionein-2 is replaced by Asp in the canine metallothionein cDNA clone. Because the acidic amino acid doesn't exist at either position 10 or 11 in the deduced amino acid sequence, it is supposed that this cDNA is derived from canine metallothionein-1 mRNA. Northern blot analysis using the cDNA as a probe revealed the induction of the canine metallothionein mRNA expression in the liver and kidney of a cadmium-treated beagle. Thus, the canine metallothionein cDNA obtained in the present study should provide an useful tool for the molecular investigation of metallothionein in dog. 相似文献
4.
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
5.
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
6.
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
7.
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
8.
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
9.
Polymer-based strong cation-exchange monolithic capillary columns with different capacities were constructed for ion chromatography by radical polymerization of glycidyl methacrylate (GMA) and ethylene dimethacrylate in a 250-microm-i.d. fused-silica capillary and its subsequent sulfonation based on ring opening of epoxides with 1 M Na(2)SO(3). The cation-exchange capacities can easily and reproducibly be controlled in the range of up to 300 microequiv/mL by changing the immersion time of the epoxy-containing polymer in the Na(2)SO(3) solution. The chromatographic performance of the produced monolithic capillary columns was evaluated through the separation of a model mixture of common cations such as Na(+), NH(4)(+), K(+), Mg(2+), and Ca(2+). As an example, these cations could be well separated from one another on a 15-cm-long cation-exchange monolithic column (column volume, 7.4 microL) with a capacity of 150 microequiv/mL by elution with 10 mM CuSO(4). The pressure drop of this 15-cm column was approximately 1 MPa at a normal linear velocity of 1 mm/s (a flow rate of 3 microL/min), and the numbers of theoretical plates for the cations were above 3000 plates/15 cm. This GMA-based cation-exchange monolithic column could withstand high linear velocities of at least 10 mm/s. Over a period of at least two weeks of continuous use, no significant changes in the selectivity and resolution were observed. The applicability of a flow rate gradient elution and the feasibility of direct injection determination of major cations in human saliva sample were also presented. 相似文献
10.
A high-efficiency cross-flow micronebulizer for inductively coupled plasma mass spectrometry 总被引:1,自引:0,他引:1
A pneumatically driven, high-efficiency cross-flow micronebulizer (HECFMN) is introduced for inductively coupled plasma (ICP) spectrometries. The HECFMN uses a smaller nozzle orifice for nebulizer gas (75 microm in diameter) and a replaceable and adjustable fused-silica capillary for sample uptake. The HECFMN is optimally operated over a wide range of sample uptake rate (5-120 microL/min) at a rf power of 1100 W and nebulizer gas flow rates of 0.8-1.0 L/min when a 50 microm i.d. by 150 microm o.d. capillary is used. The aerosol quality is qualitatively examined in a simple manner, and the transport efficiencies are determined by direct filter collection. Compared with conventional cross-flow nebulizers (CFNs), the HECFMN produces much smaller and more uniform droplets and thus provides much higher analyte transport efficiencies (generally 24-95%) at the sample uptake rates of 5-100 microL/min. Several analytical performance indexes are acquired using an Ar ICPMS system. The sensitivities and detection limits measured with the HECFMN at 50 microL/min sample uptake rate are comparable to or improved over those obtained with a conventional CFN consuming 1 mL/min sample, and the precisions with the HECFMN (typically 1.1-1.7% RSDs) are slightly better than those with the CFN (1.6-2.3% RSDs). The ratios of refractory oxide ion-to-singly charged ion (CeO+/Ce+) are typically in the range from 0.7 to 3.3% for the sample uptake rates of 5-100 microL/min. The free aspiration rate of the HECFMN is 8.9 microL/min for distilled deionized water at the nebulizer gas flow rate of 1.0 L/min without any effect of pressure. The features of the HECFMN suggest good potential for HECFMN use in interfacing ICPMS with capillary electrophoresis and microcolumn high-performance liquid chromatography. 相似文献