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Luminescence retrospective dosimetry techniques have been applied with ceramic bricks to determine the cumulative external gamma dose due to fallout, primarily from the 1949 test, in populated regions lying NE of the Semipalatinsk Nuclear Test Site in Altai, Russia, and the Semipalatinsk region, Kazakhstan. As part of a pilot study, nine settlements were examined, three within the regions of highest predicted dose (Dolon in Kazakshstan; Laptev Log and Leshoz Topolinskiy in Russia) and the remainder of lower predicted dose (Akkol, Bolshaya Vladimrovka, Kanonerka, and Izvestka in Kazakshstan; Rubtsovsk and Kuria in Russia) within the lateral regions of the fallout trace due to the 1949 test. The settlement of Kainar, mainly affected by the 24 September 1951 nuclear test, was also examined. The bricks from this region were found to be generally suitable for use with the luminescence method. Estimates of cumulative absorbed dose in air due to fallout for Dolon and Kanonerka in Kazakshstan and Leshoz Topolinskiy were 475 +/- 110 mGy, 240 +/- 60 mGy, and 230 +/- 70 mGy, respectively. The result obtained in Dolon village is in agreement with published calculated estimates of dose normalized to Cs concentration in soil. At all the other locations (except Kainar) the experimental values of cumulative absorbed dose obtained indicated no significant dose due to fallout that could be detected within a margin of about 25 mGy. The results demonstrate the potential suitability of the luminescence method to map variations in cumulative dose within the relatively narrow corridor of fallout distribution from the 1949 test. Such work is needed to provide the basis for accurate dose reconstruction in settlements since the predominance of short-lived radionuclides in the fallout and a high degree of heterogeneity in the distribution of fallout are problematic for the application of conventional dosimetry techniques.  相似文献   
146.
Individual irradiation doses were determined by electron paramagnetic resonance spectroscopy of the tooth enamel of the inhabitants of Zaborie, the most contaminated inhabited settlement not evacuated after the Chernobyl accident. Dose determination was performed using a specially developed automatic spectrum processing procedure. Spectrum processing was carried out in different operating modes, and average results were taken in order to reduce the contribution of uncertainty in dose determination caused by spectrum processing. The absorbed doses determined in enamel were corrected to take into account the contribution of natural background radiation and to determine the individual excess dose due to radioactive contamination of the territory. Individual excess doses are compared to calculated individualized doses to teeth, estimated using the local radioactive contamination levels, dose rates, and information concerning individual behavior. The individual excess doses measured by electron paramagnetic resonance spectroscopy and the calculated individualized doses are fully independent. Mean square variation between results of two methods was found to be 34 mGy, which is consistent with error estimation for both methods. This result can validate both the methodology of signal processing presented here when using electron paramagnetic resonance dosimetry of tooth enamel for low doses and the methodology of individualized dose calculation.  相似文献   
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The purpose of the study was to evaluate the efficiency of postoperative analgesia with tramal in the newborns. Analgesia with tramal (5% solution for injections, "Gruonental GmbH", Germany) was administered postoperatively in 20 newborn children. Thirteen children were operated for congenital malformations in the gastrointestinal and urinary tracts, three children were operated for purulent-septic diseases and four children were operated for neoplasms. Hemodynamics indices, i.e. heart rate (HR) and arterial pressure, as well as SaO2, respiratory rate (RR), acid-base condition and behavioral reactions were assessed. Analgesia was implemented by the method of continuous intravenous infusion of tramal, 0.1-0.2 mg/kg.h combined with boluses, 1-2 mg/kg. The newborns were asleep for a major part of time during analgesia with tamal; the stable indices of hemodynamics, acid-base balance, glycemia and of the cortisol level were registered. Arterial hypertension, caused by several factors including the effect produced by tamal, was noted in 70% of children. Dose-dependent hypercapnia was registered in 80% of tests in children at unassisted respiration during the infusion of tamal, which is indicative of that tamal affects the respiratory center during the neonatal period and that it is necessary to monitor thoroughly the respiratory functions, i.e. RR, SatO2, pO2, pCO2, and to choose accurately a preparation dose. The continuous infusion of tamal ensures a sufficient analgesia after different operations and especially after medium-traumatic operations.  相似文献   
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Nine weeks of compulsory morphine drinking decreased the specific binding of3H-muscimol to GABA receptors and14C-NAD to rat brain synaptic membranes and increased the synaptosomal uptake of14C-GABA. These effects of morphine on the GABA-benzodiazepine receptor complex were reversed by excessive doses of vitamin B3. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 127, No. 3, pp. 295–301, March, 1999  相似文献   
149.
The implantation of “ventricular assist devices??(VAD) is an effective and now well recognized surgical treatment option for patients with terminal chronic or acute heart failure. In Germany it is estimated that approximately 400??00 patients with VADs of different kinds are living in their home environments. Nevertheless, life threatening complication during MCS is rare with modern devices, but is very important that medical and paramedical personnel correctly assess emergency situations and react to them quickly and optimally. This work gives an overview of the different VAD systems and shows the procedures that are necessary in an emergency.  相似文献   
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