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101.
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RC Ziegelstein 《Canadian Metallurgical Quarterly》1996,335(1):58; author reply 58-58; author reply 59
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RC Sexton 《Canadian Metallurgical Quarterly》1998,91(10):393-396
The reasons for abandoning prophylactic vaccination against highly contagious animal diseases in the European Union on principle are illustrated. The practical implementation of control measures under the current framework are explained with respect to an outbreak of classical swine fever, emphasizing the role of the local crisis center, the veterinary diagnostic laboratories and the need for an overall control and coordination of the campaign at the regional level. In view of the continuous risk of introducing CSF virus into the domestic pig holdings different precautionary aspects under consideration are pointed out: controlled reduction of the pig unit density with the aim of establishing self-contained pig production areas versus improvement of protecting the existing individual pig holdings against introduction of infectious diseases. 相似文献
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Human auditory sensitivity for the frequencies 8, 10, 12, 16, 18, and 20 kHz was examined in a group of 41 female university students ranging in age from 19 to 22 years. The purpose of this study was twofold: to determine the feasibility of high-frequency testing using procedures routinely employed in clinical audiometry and to collect normative data using this procedure on a young adult population. A modified Hughson Westlake procedure was employed and thresholds were obtained for both ears of each subject. It was noted that for the 20-kHz tone only 52% of the subjects tested were able to respond. Statistical analysis revealed no significant threshold differences between right or left ears for all subjects at any frequency. The approach described in the present study provided reliable thresholds and was found to be clinically feasible. Comparisons were made with similar previous studies and the results of the present study were found to be in general, overall agreement. 相似文献
110.