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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.
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   
953.
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   
954.
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   
955.
A tetrapeptide RGDS (Arg-Gly-Asp-Ser), which is one of the active sites of cell adhesive proteins, was synthesized according to the solution method and covalently coupled onto monodisperse microspheres. The biospecific activity of the RGDS-carrying microspheres was investigated by measuring the stimulatory effect of the microspheres on platelets. Large and tightly packed platelet aggregation accompanied with drastic ATP release was induced by the RGDS-carrying microspheres. It was confirmed that the specific platelet aggregation was attributed to the activity of the immobilized RGDS by comparison with those induced by other microspheres.  相似文献   
956.
The previous report describes a study of the welding characteristics of an AZ31-equivalent Mg alloy welded by AC TIG arc welding. The results show this alloy to have some important welding characteristics that differ from those of the similarly welded reference Al alloy.  相似文献   
957.
958.
6-[18F]Fluoro-L-dopa (L-3,4-dihydroxy-6-[18F]fluorophenylalanine; 6-[18F]FDPA) is useful to assess presynaptic dopamine metabolism in central nervous system. In this paper, we report on the usefulness of the 6-[18F]FDOPA synthesis system developed for the routine synthesis. This system consists of the 6-[18F]FOPA synthesis and the separation units in conjunction with controller using a personal computer. The synthesis time of 6-[18F]FDOPA was 73 minutes. The typical yield and specific activity were 1.4-2.4 GBq and 244-270 MBq/mumol at the end of synthesis, respectively, under the irradiation condition of 50 microA for 130 minutes. The radiochemical yields of 6-[18F]FDOPA were 31.3-38.7% based on the [18F]acetylhypofluorite, and the results were affected with the condition of potassium acetate (AcOK) to produce gaseous [18F]acetylhypofluorite. This system is useful for the routine production of 6-[18F]FDOPA because of its high yield and high specific activity while maintaining AcOK in good condition, and decreasing the radiation exposure for chemist.  相似文献   
959.
960.
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