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951.
The activity state of branched-chain alpha-keto acid dehydrogenase complex in skeletal muscle was elevated by running exercise in trained and untrained rats, but level of this elevation was significantly greater in the former than in the latter. To elucidate the mechanism of the training effect on the exercise-induced activation of the complex, a protein amount of branched-chain alpha-keto acid dehydrogenase kinase, which is responsible for inactivation of the complex by phosphorylation, in the muscle was measured by the Western blot analysis. Endurance training decreased the content of the kinase protein in the muscle by approximately 30%, suggesting that this decrease is involved in the mechanisms for greater activation of the complex by exercise in trained rats.  相似文献   
952.
953.
The purpose of this study was to investigate the relationship between mild degrees of liver dysfunction and spontaneous intracerebral hemorrhage (ICH) from the hemostatic standpoint. A detailed study of hemostatic systems was made in 462 patients with ICH. To compare ICH with the other cerebrovascular diseases, data from 120 patients with subarachnoid hemorrhage and 114 others with cerebral infarction were reviewed. At admission, the medical histories of the patients, including information about previous alcohol consumption, was taken, and blood samples were collected to perform the following studies: platelet count, fibrinogen level, prothrombin time, activated partial thromboplastin time, antithrombin III, plasminogen and alpha 2-antiplasmin activity, platelet aggregability, and liver function tests. The incidence of liver dysfunction and alcohol consumption in patients with ICH was significantly (P < 0.05) higher than in patients with subarachnoid hemorrhage and in those with cerebral infarction. Hematoma volume, mortality rate, and past alcohol consumption in patients with ICH significantly increased with worsening severity of liver dysfunction. Although almost all hemostatic parameters became worse with increasing severity of liver dysfunction, they changed within the normal limits. Platelet aggregability and alpha 2-antiplasmin activity in patients with liver dysfunction were remarkably deteriorated beyond normal limits. In conclusion, liver dysfunction associated with alcohol consumption appears to be an important factor in the deterioration of the clinical status of patients with ICH and may be one of the causative factors in the development of ICH. Although mildly impaired hemostatic systems may be partially responsible for these adverse effects of liver dysfunction on ICH, it seems probable that nonhemostatic mechanisms are attributed to the effects.  相似文献   
954.
In a system of producing liquid ice with mechanical removing processes of mushy structure in an aqueous solution, a solid layer as thermal resistance does not stack up on a cooling surface. It prevents refrigerator's COP dropping and also prevents ice production rate dropping. However, some extra energy is needed for mechanical removing processes of the mushy structure from cooling surfaces. In this paper, the required force for removing the mushy structure is expressed as a function of experimental conditions based on bending-beam theory. The mushy structure is regarded as an elastic body. The estimated values of modulus of elasticity and values of adhesion force are reasonable compared with the observed results. Parameters that affect on mode difference, maximum force and steady force are shown.  相似文献   
955.
High-isolation polarization-independent quasi-optical circulator   总被引:2,自引:0,他引:2  
A polarization-independent quasi-optical circulator having high isolation over a wide wavelength range is reported. The proposed quasi-circulator is composed of two polarization beam splitters, two pentagonal prisms, two nonreciprocal rotators, and two walkoff polarizing beam splitters. Its structure is very simple. A three-port quasi-circulator has been fabricated with single-mode fibers. Its insertion loss and isolation have been measured to be ⩽1.7 and ⩾48.6 dB, respectively, at the nominal wavelength of 1.3 μm. A loss ratio of over 47.0 dB has been realized. The wavelength range over a 50-dB isolation between two fibers was measured to be about 50 nm  相似文献   
956.
An automatic method for self-calibrating six-port reflectometers is reported in this paper. It is based on the use of an active impedance synthesis system. This self-calibration method allows a completely autonomous operation, reduces measurement errors caused by the frequent connecting and disconnecting of calibration standards, and is suitable for low and high frequencies, where sliding shorts are difficult to manufacture. In addition, it simplifies operation of six-port reflectometers to nonspecialized users. The experimented impedance synthesis presented relies on an in-phase and quadrature vector modulator, and the entire system is computer controlled  相似文献   
957.
The specific heat of copper potassium tutton salt has been measured down to 1 mK in order to investigate the hyperfine interaction of this copper compound. The magnetic ordering of the electronic system occurs at 29.5 mK in zero field. Below the transition temperature the electronic heat capacity decreases and the copper nuclear heat capacity of hyperfine splitting becomes dominant in the heat capacity of the compound. The nuclear heat capacity has a broad peak around 3.5 mK. The entropy of copper nuclear spin, which was calculated from the specific heat data, remains at 40% of ln(2I+1) at 1 mK.  相似文献   
958.
We used fMRI to compare the ipsilateral activation in the sensorimotor region (SMR) during dominant and non-dominant hand motor tasks between right and left handers. In right handers, the ipsilateral activation was significantly greater during non-dominant (left) hand task than dominant (right) hand task, while in left handers, it showed no significant difference. The ipsilateral activation was most pronounced in the precentral subregion (presumably corresponding to the premotor area) during either hand task in both groups. We conclude that the different patterns of ipsilateral activation might be mainly explained by the hemispheric dominance. The skill of the hand and complexity of tasks may be related to the predominant activation of the premotor area.  相似文献   
959.
We observed a few rare spontaneous cases of a suddenly widened QRS wave of left ventricular ECG associated with a simultaneous decrease in left ventricular (LV) contractility (Emax, end-systolic pressure-volume ratio) in excised cross-circulated dog heart experiments. The decreased Emax was not associated with a descent of the relation between cardiac oxygen consumption (VO2) and LV systolic pressure-volume area (PVA, a measure of total ventricular mechanical energy). This result is intriguing because ventricular VO2-PVA relation generally changes its elevation in proportion to Emax under various inotropic interventions. We suspected the unusual observation to reflect no change in myocardial contractility despite ventricular asynchrony augmented by an intraventricular conduction defect.  相似文献   
960.
We purified the toxin of Aeromonas sobria capable of inducing a positive response in the mouse intestinal loop assay. The purified toxin showed a positive response not only in the loop assay but also in a hemolytic assay. Subsequently, we cloned the toxin gene and demonstrated that the product of this gene possessed both hemolytic and enterotoxic activities. These results showed that the enterotoxin of A. sobria possesses hemolytic activity. Nucleotide sequence determination of the toxin gene and amino acid sequence analysis of the purified toxin revealed that it is synthesized as a precursor composed of 488 amino acid residues, and that the 24 amino-terminal amino acid residues of the precursor is removed in the mature toxin. As antiserum against the purified toxin neutralized the fluid accumulation induced by living cells not only of A. sobria but also of A. hydrophila, this and antigenically related toxin(s) are thought to play an essential role in the induction of diarrhea by these organisms. The toxin-injured Chinese hamster ovary (CHO) cells induced the release of intracellular lactose dehydrogenase (LDH). The release of LDH from CHO cells and the lysis of erythrocytes by the toxin were repressed by the addition of dextran to the reaction solution, indicating that the toxin forms pores in the membranes and that the cells were injured by the osmotic gradient developed due to pore formation. However, the histopathological examination of intestinal cells exposed to the toxin showed that it caused fluid accumulation in the mouse intestinal loop without causing cellular damage.  相似文献   
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