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1.
We performed a cross-sectional survey of stroke and acute myocardial infarction (AMI) in Okinawa, Japan with a census population of about 1.2 million. A total of 3,644 cases of first-ever stroke and 898 cases of initial acute myocardial infarction (AMI) were detected. The age-adjusted annual incidence rate for stroke was 105 per 100,000 standard population of Japan, and that of AMI was 26. The case-fatality rate of stroke within 28 days of onset was 12.8%, and that of AMI was 22.2%. Of the stroke cases, 51.4% were diagnosed as brain infarction, 38.7% as brain hemorrhage, and 9.3% as subarachnoid hemorrhage. The diagnosis of stroke subtypes were confirmed by computed tomography or magnetic resonance imaging in 98.4% of all stroke cases. In Okinawa, the incidence rate of AMI was still considerably lower than that in the Western population, and the rate of stroke was similar to that in the Western population.  相似文献   
2.
A full-length cDNA clone for a progesterone membrane binding protein from porcine vascular smooth muscle cells was isolated and the complete nucleotide sequence determined. The cDNA encodes a protein of 194 amino acids with a transmembrane segment. This protein is likely to represent the first steroid membrane receptor or a part of it for which sequence information is available.  相似文献   
3.
We developed a new simple assay for the quantitation of the activities of drugs against intracellular Legionella pneumophila. The cells of a murine macrophage-like cell line (J774.1 cells) allowed the intracellular growth and replication of the bacteria, which ultimately resulted in cell death. The infected J774.1 cell monolayers in 96-well microplates were first treated with antibiotics and were further cultured for 72 h. The number of viable J774.1 cells in each well was quantified by a colorimetric assay with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and an enzyme-linked immunosorbent assay reader. The number of growing bacteria in each well was also determined by counting the numbers of CFU on buffered charcoal yeast extract-alpha agar plates. Viable J774.1 cell counts, determined by the colorimetric assay, were inversely proportional to the number of intracellular replicating bacteria. The minimum extracellular concentrations (MIECs) of 24 antibiotics causing inhibition of intracellular growth of L. pneumophila were determined by the colorimetric assay system. The MIECs of beta-lactams and aminoglycosides were markedly higher than the MICs in buffered yeast extract-alpha broth. The MIECs of macrolides, fluoroquinolones, rifampin, and minocycline were similar to the respective MICs. According to their intracellular activities, clarithromycin and sparfloxacin were the most potent among the macrolides or fluoroquinolones tested in this study. Our results indicated that the MTT assay system allows comparative and quantitative evaluations of the intracellular activities of antibiotics and efficient processing of a large number of samples.  相似文献   
4.
It is well-known that polypropylene (PP) is difficult to process as a consequence of its linear structure. It is also known that grafting of long-chain branches on PP backbone using ionizing radiation is an effective approach to achieve high melt strength polypropylene (HMS PP). Chain-scission and, in minor extend, crosslinking and grafting are the predominant reaction in order to branch PP backbone. However, if multifunctional monomers are used to promote the grafting reaction, crosslinking can surpass chain scission and grafting, reducing drawability. Therefore, in an effort to enhance the processability and so the drawability, it has been found helpful to add a small amount of polybutene-1. Gamma irradiation technique was used to induce chemical changes in blends of PP and polybutene in acetylene atmosphere (crosslinker promoter) and in HMSPP/polybutene blends. The samples were irradiated with a 60Co source with doses of 12.5 and 20 kGy in the presence of acetylene. In this work, two different methods of blends processing were compared regarding rheological and mechanical properties. Effects on the strength and elongation at the yield point and at rupture were observed by mechanical tests and showed decrease of tensile strength and increase of elongation at rupture for samples obtained by irradiation of blends. The results from rheology demonstrated an increase in melt strength and drawability of blends.  相似文献   
5.
Unlike the conventional transient hot-wire method for measuring thermal conductivity, the transient short-hot-wire method uses only one short thermal-conductivity cell. Until now, this method has depended on numerical solutions of the two-dimensional unsteady heat conduction equation to account for end effects. In order to provide an alternative and to confirm the validity of the numerical solutions, a two-dimensional analytical solution for unsteady-state heat conduction is derived using Laplace and finite Fourier transforms. An isothermal boundary condition is assumed for the end of the cell, where the hot wire connects to the supporting leads. The radial temperature gradient in the wire is neglected. A high-resolution finite-volume numerical solution is found to be in excellent agreement with the present analytical solution.  相似文献   
6.
A measurement method for PVT properties of high-temperature and high-pressure gases was developed by simplifying the Burnett method and revising the data acquisition procedure. Instead of a differential pressure transducer, which is traditionally used, an absolute pressure transducer is used in the present method, and the measurement of pressure becomes easier. However, the absolute pressure transducer is placed outside the constant temperature bath because of the difficulty of its use in high-temperature surroundings, and some parts with different temperatures from the sample vessels exist as dead space. The present method takes into account the effect of the dead space in the data acquisition procedure. Nitrogen was measured in the temperature range from 353 K to 473 K and at pressures up to 100 MPa to determine the apparatus constants, and then, hydrogen was measured at 473 K and up to 100 MPa. The determined densities are in agreement within uncertainties of 0.07% to 0.24% (k = 2), both with the latest equation of state and existing measured data.  相似文献   
7.
A dynamic simulation approach to investigate an optimal hydrogen refueling method is proposed. The proposed approach simulates a transient temperature, pressure and mass flow rate of hydrogen flowing inside filling equipment in an actual station during the refueling process to an Fuel Cell Vehicle (FCV) tank. The simulation model is the same as in an actual hydrogen refueling station (HRS), and consists of a Break-Away, a hose, a nozzle, pipes and an FCV tank. Therefore, we can set actual configurations and thermal properties to the simulation model, and then simulate the temperature, pressure and mass flow rate of hydrogen passing through each position based on the supply conditions (temperature and pressure) at the Break-Away. In this study, the simulated temperature, pressure and mass flow rate are compared with the corresponding experimental data. Therefore, we show that the dynamic simulation approach can accurately obtain those values at each position during the refueling process and is an effective step in proposing the optimal refueling method.  相似文献   
8.
A 10-wk randomized complete block design experiment with 24 Holstein cows was conducted to investigate the long-term effects of feeding a His-deficient diet on lactational performance of dairy cows. Cows were blocked by days in milk, milk yield, and parity, and randomly assigned to 1 of the following 2 treatments: (1) His-adequate diet [HAD; providing +166 g/d over metabolizable protein (MP) requirements, according to the National Research Council (2001) and digestible His (dHis) supply of 68 g/d, or 2.5% of MP requirements] and (2) His-deficient diet (HDD; +37 g/d over MP requirements and dHis supply of 49 g/d, or 1.9% of MP requirements). Both HAD and HDD were supplemented with rumen-protected (RP) Met and Lys supplying digestible Met and digestible Lys at 2.4 and 2.4% and 7.2 and 7.1% of MP requirements, respectively. At the end of the 10-wk experiment, HDD was supplemented with RPHis (HDD+RPHis; total dHis supply of 61 g/d, or 2.4% of MP requirements) for an additional 9 d. Dry matter intake (DMI; 25.4 and 27.1 kg/d, standard error of the mean = 0.41), yields of milk (37.6 and 40.5 kg/d, standard error of the mean = 0.62), protein and lactose, energy-corrected milk, and milk and plasma urea-N were decreased by HDD compared with HAD. Feed and energy-corrected milk feed efficiencies, milk fat, protein and lactose concentrations, body weight, and body condition score of the cows were not affected by treatment. Apparent total-tract digestibility of dry and organic matter, crude protein, and neutral detergent fiber, and excretion of urinary N and urea-N were decreased by HDD compared with HAD. Concentration of plasma leptin tended to be decreased for HDD compared with HAD. Plasma concentrations of EAA (His, Leu, Lys, Val) and carnosine decreased and total EAA tended to be decreased in cows fed HDD compared with HAD. Muscle concentrations of free His, Leu, and Val decreased and Gly and β-alanine tended to be increased by HDD compared with HAD. Cows fed HDD had a lower blood hemoglobin concentration than cows fed HAD. At the end of the 10-wk study, the 9-d supplementation of HDD with RPHis (i.e., HDD+RPHis) increased DMI and plasma His, and tended to increase energy-corrected milk yield and plasma carnosine, compared with HDD. In conclusion, feeding a diet deficient in dHis supplying adequate MP, digestible Met, and digestible Lys affected negatively lactational performance of dairy cows. These results confirm our previous findings that low dietary His supply can impair DMI, yields of milk and milk protein, and blood hemoglobin in dairy cows.  相似文献   
9.
A two-dimensional analytical solution is derived for the three-omega method for measurement of thermal conductivity of materials with a fine wire. The analytical solution includes the wire heat capacity and the effect of heat losses from the ends of the wire. To derive the solution, finite Fourier transforms are applied in the direction parallel to the wire axis. The solution is compared with a one-dimensional solution and experimental data. It is found that heat losses from the wire ends have a significant effect on the 3ω components at low frequency and tend to be less important at high frequency. Moreover, it is shown that two-dimensional effects will be severe for nano-scale wires, even if the wire length-to-diameter ratio is very large.  相似文献   
10.
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