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Effects of single, double, and rhythmic stimulation upon hypothalamic neurons responding to the 1st excitatory phase of lateral vestibular nucleus stimulation, were studied. The data obtained show that activation of some hypothalamic neurons following stimulation of the lateral vestibular nucleus has a monosynaptic character. The findings suggest that ascending afferents from the lateral vestibular nucleus to the hypothalamus pass via oligo- as well as polysynaptic pathways.  相似文献   
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The effect of two weeks administration of a uricosuric diuretic (SKF-62698) on renal urate handling has been examined in 11 normal men. Plasma urate concentrations had declined by more than 60 per cent after two weeks. Urate excretion per unit of glomerular filtration rate and urate clearance (Curate) per unit of glomerular filtration rate were increased after the administration of SKF-62698. The importance of intact tubular secretion of urate in producing these changes was assessed by administering pyrazinamide, an agent that curtails urate secretion, to each participant. The decrements in urate excretion and clearance produced by pyrazinamide both increased significantly, whereas the residual urate excretion rates and clearances not suppressible by pyrazinamide were only minimally altered by SKF-62698 treatment. These results suggest that the excretion of secreted urate was enhanced by prolonged administration of SKF-62698, probably secondary to the inhibition of postsecretory urate reabsorption. In addition, because the nonsuppressible urate excretion did not decline despite a 63 per cent reduction in the plasma urate, it is likely that the reabsorption of filtered urate also was impaired by SKF-62698.  相似文献   
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Coke with ore additive may be produced from Zarechnaya DG coal (Kuznets Basin) and high-sulfur Zh coal (from Samsonovskaya and Krasnolimanskaya enrichment facilities, Donets Basin), which is of low technological value and is used in small quantities in batch for the production of blast-furnace coke. The ore additive employed is dust from the dry gas purifiers in the production of commercial silicomanganese, manganese-carbonate concentrate, and manganese-oxide concentrate of the first and second kinds. In experimental batches, the content of the ore additive is adjusted in 5% increments over the range 0–15%. On introducing the ore additive in the batch, the corresponding quantity of G coal is removed, with constant content (40%) of Zh coal. Experimental batches are coked in a 5-kg laboratory furnace (designed by Ukrainian Coal-Chemistry Institute). The coke obtained is tested by methods including technical analysis and determination of the electrical resistivity, the reactivity, and the structural and mechanical strength. In the production of highly reactive coke with high electrical resistivity, the best ore additive is 10–15% manganese-oxide concentrate. The coke is suitable for transportation, transfer, sorting, and crushing to the required size.  相似文献   
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Radioactive waste arranged inside the container releases heat as a result of radioactive decay. If the heat power is sufficient, the geological rock near the container melts and the container moves into the Earth's depths. This method of self-immersion of radioactive waste may be suggested as an additional method to the deep geological disposal approach. The basic problem of method realization is to find a container material that remains firm in a temperature of about 1300–1400°C in melted rock (for example basalt). This problem is considered in connection with the question of radioactive matrix choice and compatibility of materials.  相似文献   
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In this paper perceived stress at work is examined in a nationwide representative sample of Norwegian physicians. Four questions were asked about how often the doctors experienced their working conditions as hectic and bothersome, that the work load was unacceptable, that the large number of duties prevented them form working effectively and that they had difficulty in working reasonably undisturbed. 28% of the respondents stated that their work load was often or fairly often unacceptable, while 43% often or fairly often found it difficult to carry out various tasks without being disturbed. While 19% of the physicians perceived their working situation as often hectic and bothersome, the corresponding figure among other academics was 5%. When the four questions were combined to form a measure of stress, about one fifth of the doctors proved to be highly stressed. In a multiple linear regression analysis (N = 2,304) the physician's perceived autonomy was the strongest predictor of stress, i.e. doctors who feel they can substantially influence the planning and organization of their work achieve the lowest scores for stress. Heads of hospital departments are more stressed than physicians who work outside hospital. Stress also increases with increasing frequency of overtime and with increasing amounts of voluntary overtime.  相似文献   
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BACKGROUND: The distinction between malignant mesothelioma (MM) and adenocarcinoma (ACA) in cytologic specimens frequently is difficult, often requiring immunocytochemistry to support the diagnosis. Recent reports have proposed the utilization of antibodies to mesothelial cell clone HBME-1 and thrombomodulin (TM), because they are immunoreactive in MM and less commonly reactive in ACA. Immunoreactivity for the monoclonal antibody CA 19-9 has been observed in many ACAs and reportedly is absent in MM. METHODS: In this study, immunostaining was performed on formalin fixed, paraffin embedded cell blocks from effusions or fine-needle aspirations using the avidin-biotin-peroxidase method. Thirty-eight MMs and 49 ACAs were tested using antibodies to CA 19-9, HBME-1, and TM. RESULTS: Anti-CA 19-9 stained only 1 of the 37 cases of MM tested (3%), but stained 24 of the 49 cases of ACA (49%). Anti-HBME-1 stained 34 of 38 cases of MM (89%), and 28 of 43 cases of ACA tested (65%). Anti-TM stained 24 of 36 cases of MM (67%), and 21 of 40 cases of ACA tested (53%). CONCLUSIONS: CA 19-9 has utility as part of an immunocytochemical panel for distinguishing ACA from MM, because a positive staining reaction would make the diagnosis of MM unlikely. Although HBME-1 and TM can identify MM positively, each frequently is detected in ACA, thus limiting the utility of these antibodies in cytologic specimens.  相似文献   
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