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Abstract  

In order to estimate gut absorption by determining tracer concentration in plasma, a technique based on the administration of two stable isotopes of the same element was combined with proton activation analysis. The optimization for the determination of Zr isotopes in biological samples is presented together with the results of a preliminary study on Zr biokinetics in animals. (p,n) reactions on90Zr and96Zr resulted the most convenient. The obtained minimum detectable quantities are 3 and 2 ng/ml plasma, respectively, for90Zr and96Zr. Zr plasma clearance and Zr response to a simple oral test were studied separately in different subjects by using the natural Zr solution. The data analysis was performed measuring the concentration of90Zr to obtain indication on the time behavior and fractional level of Zr appearance in plasma depending on the administration routes. Two rabbits were intravenously injected 50 g90Zr and a third rabbit was orally given 2.5 mg of90Zr. Concentration in plasma samples of intravenously and orally given Zr isotopes are reported, as a function of time after administration. The injected tracer concentration relative to the first two rabbits were fitted simultaneously to obtain clearance parameters. Zr intestinal absorption is evaluated to be less than 0.2%. The work confirms that proton activation is a powerful tool for biokinetic studies with stable isotopes.

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Automated behavioural observations are routinely used in many fields of biology, including ethology, behavioural ecology and physiology. When preferences for certain resources are investigated, the focus is often on simple response variables, such as duration and frequency of visits to choice chambers. Here we present an automated motion detector system that use passive infrared sensors to eliminate many drawbacks of currently existing methods. Signals from the sensors are processed by a custom-built interface, and after unnecessary data is filtered by a computer software, the total time and frequency of the subject’s visits to each of the choice chambers are calculated. We validate the detector system by monitoring (using the system) and in the same time video recording mating preferences of zebra finches in a four-way choice apparatus. Manual scoring of the video recordings showed very high consistency with data from the detector system both for time and for frequency of visits. Furthermore, the validation revealed that if we used micro-switches or light barriers, the most commonly applied automatic detection techniques, this would have resulted in approximately 22% less information compared to our lossless system. The system provides a low-cost alternative for monitoring animal movements, and we discuss its further applicability.

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Abstract  

Element concentrations in biological tissues of Dmdmdx/J and C57BL/6 J mice strains were determined using the neutron activation analysis technique. Samples of whole blood, bones and organs (heart and muscle) of these strains were irradiated in the IEA–R1 nuclear reactor at IPEN-CNEN/SP (Brazil). To perform this investigation biological samples of two-month-old adult females (n = 10) and males (n = 9) for Dmdmdx/J (dystrophic mice), and males (n = 12) for C57BL/6 J (control group), originally obtained from the Jackson Laboratory (Maine, USA) and further inbred at IPEN–CNEN/SP (São Paulo, Brazil), were used. A significant change was observed in the analysis of the heart of dystrophic mice suggesting that this dysfunction affects severely the heart muscle. These data may, in the future, contribute to the healthcare area, in veterinary medicine and in the pharmaceutical industry allowing the evaluation of the best procedures in diagnosis, treatment and investigations of neuromuscular diseases (muscular dystrophy) of patients through the use of animal models.

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állatmaradványok Segesdről (Medieval and Turkish Period animal bones from Segesd, Southwestern Hungary). SMK 12 (1996) 183–222. Bartosiewicz L. Középés török kori állatmaradványok Segesdről

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Fujiwara, K. and Horiuchi, S. (1990): Chicken. In: Fujiwara, K. and Horiuchi, S. (eds) Experimental Animals for Toxicity Tests. Chijin Syokan, Tokyo. pp. 101-110. Chicken 101

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Domahidi, I., Egyed-Zsigmond, I., Kolozsvári, É., Peti, A.: The acute effect and histopathological changes produced by methol in experimental animals, (in Romanian), Revista Românâ de Medicina Muncii 48 (3-4), 10015-10019 (1998

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– . Kesmen , Z. , Sahin , F. & Yetim , H. ( 2007 ): PCR assay for the identification of animal species in cooked sausages . Meat Sci. , 77 , 649 – 653

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, corresponding to the first stage of decomposition is the most important value for the characterization of vegetable or animal fats thermal stability, since based on the starting temperature of thermal decomposition, different types of oil stability and the

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Abstract  

The definition of dose-response relationships in man is the essential requisite to set scientifically health protection standards for the evaluation of a safe level exposure of humans to heavy metals. The derivation of these relationships requires sequential multidisciplinary informations including data on metabolic patterns and biochemical effects in mammals. Unfortunately, sufficient data are not available to establish dose-response curves expecially in long term-low level exposure conditions and a need exists to gather such informations for each metal on absorption, distribution and excretion in laboratory animals and humans. This paper: (1) discuss main problems related to the use of NAA in metallobiochemistry of present levels of trace elements; (2) report data on the current applications of NAA in metallobiochemistry in relation to the work carried out in the context of a project Heavy Metal Pollution of CEC JRC—Ispra. Applications deal with in vivo studies on laboratory animals, in vitro studies on biochemical systems and experiments on tissues of human origin; (3) discuss the perspectives of the use of the nuclear techniques in the environmental toxicology.

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Animals . St. Peterburg: Nauka. Ivanova-Kazas O. M. Evolutionary Embryology of Animals 1995

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