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1.
OBJECTIVE: Ischaemic preconditioning protects myocardium from infarction if the reperfusion interval between the brief and prolonged ischaemic intervals is less than 1 h. In anaesthetised rabbits acadesine (5-amino-4-imidazolecarboxamide riboside, AICAR), an adenosine enhancer which increases tissue adenosine during ischaemia, prolongs the window of protection to 2 h. The aim of this study was to try to determine the maximum extension of this window of protection, using chronically instrumented, unsedated rabbits. METHODS: Rabbits were instrumented with a balloon occluder around a major branch of the left coronary artery for reversible coronary occlusion. Five to seven days after surgery all animals underwent a 30 min coronary occlusion. Animals were randomised to one of seven groups: (1) No additional treatment (control); (2) Ischaemic preconditioning with 5 min regional ischaemia followed by 10 min reperfusion before the 30 min coronary occlusion; (3) and (4) Ischaemic preconditioning followed by 2 or 4 h of reperfusion before the 30 min occlusion, respectively; (5) Treatment with acadesine (2.5 mg.kg-1.min-1 intravenously for 5 min and then 0.5 mg.kg-1.min-1 beginning 45 min before and continuing until 30 min after release of the 30 min occlusion) without ischaemic preconditioning; (6) and (7) Treatment with the higher dose of acadesine for 5 min beginning 35 min before the 5 min ischaemic period, and then the lower dose continuing until 30 min after release of the 30 min coronary occlusion in rabbits with 4 or 6 h reperfusion intervals, respectively. RESULTS: Rabbits with ischaemic preconditioning with 10 min reperfusion preceding the 30 min coronary occlusion (group 2) had only 5.6(SEM 1.1)% infarction of the ischaemic zone. Ischaemic preconditioning followed by 2 h reperfusion (group 3) offered continued protection [18.2(2.2)% infarction] as compared to control animals [37.7(2.6)% infarction]. However, protection waned if ischaemic preconditioning was followed by 4 h reperfusion (group 4) [36.7(3.0)% infarction]. Additionally, treatment with acadesine alone did not modify infarct size (group 7) [39.5(4.0)%], but acadesine largely restored the protection of ischaemic preconditioning despite a 4 h reperfusion interval (group 5) [20.4(3.0)% infarction, P < 0.01 v control]. However, when reperfusion was extended to 6 h (group 6) acadesine could no longer restore protection [36.2(0.9)% infarction]. CONCLUSIONS: The protection afforded by a 5 min ischaemic preconditioning period lasts from 2 to 4 h in the awake, unsedated rabbit, and acadesine can extend the duration of this window of protection to at least 4 h but not to 6 h.  相似文献   
2.
Summary Giant hybrid liposomes of polymerizable lipid and cholesterol were prepared by the hydration method and were polymerized by UV irradiation. The obtained giant liposomes were freeze-dried and washed with chloroform to skeletonize the frame structure of the polymerized membrane. The skeletonized liposomes were directly confirmed by scanning electron microscopy. The single-layered and fully spherical liposome frame were easily confirmed by the stereo-pair of the obtained micrographs.  相似文献   
3.
This article argues for a theoretical framework of alternative economics pertinent to Sustainable Development. The alternative economics requires an appropriate belief/value system based on a dynamic, sound and holistic society-specific culture (abbreviated as “Culture”). To represent the Culture-based belief/value system, a general framework for overarching Integral Harmony is introduced as an appropriate social value system for a paradigm shift toward sustainability. Such a social value system is now related to the value premises of the alternative economics. Then, the framework of alternative economics is explained in terms of basic theoretical construct that is simplified as a summary equation comprising value and real aspects. Finally, a typical working of the alternative economics is demonstrated diagrammatically as constant interactions of the value aspect and the real aspect (abbreviated as “Value-Real Interactions”).  相似文献   
4.
We experimentally found the unexpected phenomena of scattering in laminated polarization splitters (LPS's) composed of a-Si:H-SiO(2) multilayer and studied its mechanism. The scattering phenomena strongly depend on the incident angle and polarization of the incident light. To reduce the scattering loss in LPS's, a multilayer with flat layer boundaries is fabricated with rf bias sputtering. As a result, the insertion loss of the LPS is reduced to ~ 1 × 10(-3) dB/ μm, which is acceptable for practical uses.  相似文献   
5.
With the developments in power electronics equipment, the electromagnetic environment has become severe for electronic equipment. In the smart facility field, the stable operation of electronic devices is indispensable, and noise countermeasures must be improved. To suppress intrusive noise from cables, shielded cables are used in many cases. However, electromagnetic induction cannot be suppressed when the shield is grounded at one end, and when grounding both ends of the shield, current flows through the shield creating intrusive noise in the cable. That is, even if a shielded cable is used, a sufficient effect cannot be obtained. Therefore, as a countermeasure, this study prototypes and evaluates cables that combine double shielded cables with magnetic cores. Evaluations conducted using the copper pipe method, triaxial method, and impulse test confirm that the shielded performance improved by 10–30 dB compared with the conventional shielded cable.  相似文献   
6.
An intelligible program diagram called Logichart has been developed for Prolog visualization. Its syntax rules and layout rules are formalized in terms of an attribute graph grammar. This grammar is underlain by a context–free graph grammar whose productions are defined to formalize the graph–syntax rules of Logichart diagrams. Semantic rules attached to the productions are defined in such a way that they can extract the layout information needed to display a Logichart diagram as attributes. Our Prolog visualization system, which has been implemented based on the attribute graph grammar, can draw a Logichart diagram for any correct Prolog program (completeness), and any Logichart diagram displayed by the system is always valid for the grammar (soundness). The system can also display the execution of a Prolog program in real time; that is, the Logichart diagram is dynamically updated as the program runs.  相似文献   
7.
Experience with Radio Isotope Myelography is reported here. 169Yb-DTPA as a tracer was intrathecally injected at lumbar region in twenty three patients with various spinal cord lesions. The first scanning is perfomed after comfirming by gamma-camera that the tracer reaches to the lesion, the second and the third scannings are done according to the ascending rate of the tracer. (I) Normal scintimyelogram (A) In normal case, the shape of the Radio Isotope Myelogram well corresponds the shape of anatomical subarachnoid space. (B) In normal adult cases, the tracer comes up to the cisterna magna in 20-25 minutes after the lumbar injection. Therefore, the scintimyelographic diagnosis should be made not only by the shape but also by the ascending rapidity of the tracer. (II) Abnormal scintimyelogram Abnormal scintimyelograms could be summarized as following three categories. (A) "Delay": It means delay of the ascending of the tracer. Besides, "Transient delay" found in a case of Arnord-Chiari's malformation was proposed. (B) "Partial block": It meas a defect at the level of the lesion. This "Partial block" were observed in cases of spinal cord angioma, cervical spondylosis and spinal cord tumor etc. (C) "Complete block": It means the stagnation of the tracer below the lesion. To sum up, Rario Isotope Myelography, especially in partial block, can more easily and more sensitively represent the maximum extent of the spinal cord lesion than other myelographic study or angiographic one. On the other hand, we can not qualitatively diagnose about the lesions by its indistinct border.  相似文献   
8.
Recently, a great deal of foreign investment has been entered into construction of the social infrastructure of Myanmar. Many construction projects are therefore on-going, and these are especially planned in the Yangon area. While these construction booms are increasing, existing studies on the geotechnical problems in the Yangon area such as problematic soils like soft clays are limited at present. Information on soil properties has also not been shared and has been confined to individual projects. In this paper, the boring and laboratory tests carried out in the Yangon area are selected and focused upon among the tests carried out in Myanmar. Laboratory test results for clay deposits in the Yangon area are analyzed and the differences in soil properties between different sedimentary basins and sub-areas divided by the Tertiary sediment ridge that runs from north to south at the center of Yangon are clarified together with a comparison to the clays found in other countries, which have been previously investigated.  相似文献   
9.
This study was intended to examine the mechanism of multiple slope failures and debris flows that occurred in the outskirts of Hiroshima on 20th August 2014. A field survey of the mountain stream where large-scale damage was incurred was carried out and the characteristics of debris flows which made serious damages were investigated. There were five findings of this study. (1) The initiation of debris flows was not limited to thin and planar shallow failures, but also showed V or U shapes, where the eroded sediments seemed to be pushed out by artesian water, and the eroded depth exceeded several meters at many locations. (2) There were areas with high permeability, such as faults, fracture zones, and joints in Mt. Abusan. It is inferred that the constantly present groundwater in these areas became artesian water because of a large amount of rainfall in upstream locations. This quickly destabilized the slopes on a large scale. (3) There were at least three estimated debris flows at the mountain stream above Midorigaoka prefectural apartments in Yagi 3-Chome, where the worst damage occurred. The mountain stream near Abu-no-Sato housing complex also had multiple debris flows. Here, the secondary debris flow changed its flow path because of the presence of sediments from an earlier debris flow. (4) The actual volumes of flowed mass were much larger than that predicted at 11 of the 18 mountain streams in Midori-i and Yagi districts. The volume of the mass of five of these mountain streams was more than twice the estimated volume. It is necessary to modify the method of calculating the volume of unstable sediments in the mountain stream. (5) It was found that the devastating damage of buildings and human lives took place in the areas well beyond the special restricted zones. The present method to designate the special restricted zone must be revised considering such problems as the underestimation of the volume of unstable sediments, the assumptions of a single debris flow and on the direction of debris flow, and the effect of the difference on rock and soil types.  相似文献   
10.
Speech signals generally have many intervals with low energy “energy dips”. For music signals, energy dips are not always remarkable. We studied stochastic features of energy dips for speech and music signals. A certain difference was found between the signals in the length of energy dips. Also, the number of energy dips in a time window and their distribution were investigated. From this distribution, a threshold number of energy dips was estimated which provided a scheme for the discrimination of speech from music.  相似文献   
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