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1.
B Hofírek P Horín M Granátová M Machatková J Franz I Svoboda J Blecha 《Veterinární medicína》1986,31(3):129-140
A trial was performed with heifers at the age of six to seven months. The animals were experimentally infected with the lymphocytes of a virus-productive donor. Infection was produced in all the nine cases, as demonstrated by means of the positive syncytial test. As indicated by the results of the trial, the antibodies to the enzootic bovine leucosis virus (BLV) were produced soon after experimental infection. A high sensitivity of the serum-neutralization test and the ELISA method was demonstrated in this connection: by these methods, the antibodies were identified already two to three weeks after experimental infection whereas by the immunodiffusion test they could be detected only after five weeks. Twenty-four animals were exposed to natural contact infection. Within 270 days of the trial, the disease after contact was recorded only in one heifer out of the four that were in close contact with the experimentally infected animals. In this case, as compared with experimental infection, the antibodies were produced much later--after 85 to 93 days. Leucosis was recorded in none of the remaining animals. The reasons why such a favourable result was obtained were the thorough disinfection of the stables after blood collections and the strict observance of the aseptic conditions. The results of experimental infection in three cows were identical with those obtained in young cattle. In the experimentally infected dairy cows, antibodies in milk were determined by the ELISA method. As found, in milk the antibodies to BLV appear two to three weeks later than they do in serum. The ELISA method of BLV antibody detection can be used for the identification of infected animals in herds where enzootic bovine leucosis occurs. 相似文献
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Franz F 《Science (New York, N.Y.)》1949,109(2836):466-467
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Dr. Franz Hengl 《Journal of pest science》1925,1(3):27-28
Ohne Zusammenfassung 相似文献
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European Journal of Forest Research - Anhand yon Wuchsmodellen wird die Bestandesentwicktung der Kiefer bei unterschied-licher Begrüindungsdichte und Bestandesbehandlung dargestellt. Neben... 相似文献
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Veterinarians are often directly involved in clinical studies or requested for information to help interpret their results. Therefore, it is reasonable to examine the reservoir of study methods. This article transfers methodological considerations from clinical research into veterinary medicine. The study question determines the appropriate study method. Recently a ten-step procedure was suggested for selection of appropriate study designs in humans. Based on this approach, a pragmatic study design was adapted to the conditions prevailing in interventional studies in dogs and cats with disturbed behaviour. The different concepts for clinical studies are introduced. Whether or not the design and the evaluation of pragmatic studies in dogs and cats with disturbed behaviour has been maintained and the prerequisites have thereby been fulfilled so that the obtained results are suitable to be applied under everyday conditions can be tested in eight steps. Using the pragmatic design the superiority of complex interventions can be investigated. The results of pragmatic studies help to substantiate a value judgement, i. e., the recommendation or rejection of a specific therapeutic intervention for a defined disease entity in a specific therapeutic setting. The goal of pragmatic studies is to obtain results appropriate for use in everyday situations. In conclusion, the suggested procedure is useful for the selection of the appropriate study designs for specific questions. This procedure is also suitable to test whether the conclusions of published study results coincide with the chosen methods. 相似文献
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Conraths FJ Köhler H Werner O Beer M Depner KR Geue L Kaden V Staubach C Pötzsch C Schares G Mettenleiter TC 《Berliner und Münchener tier?rztliche Wochenschrift》2005,118(9-10):354-364
The Friedrich-Loeffler-Institut, founded in 1910 by Friedrich Loeffler, the discoverer of the first animal virus, foot-and-mouth disease virus, is the oldest virological research facility in the world. Beyond viruses, its area of competence has significantly expanded since its foundation and now also covers bacterial, parasitic and prion diseases of livestock, poultry and aquatic animals. Presently located at four sites within Germany (Insel Riems, Jena,Tübingen,Wusterhausen) the tasks of the institute as delineated in the Animal Disease Act encompass research on infectious animal diseases including zoonoses, import/export examinations, epidemiological studies in case of outbreaks of notifiable animal diseases, acting as reference laboratory for notifiable animal diseases and nationwide quality management of diagnosis of notifiable animal diseases. It is obliged to publish and maintain up-to-date diagnostic regimes for notifiable animal diseases, and it publishes a yearly report on animal health in Germany. With the increasing importance of infectious diseases of animals, in particular those potentially harmful to man (zoonoses), the Friedrich-Loeffler-Institut will be moving into new facilities including laboratories and animal facilities up to the highest biosafety level at its main site Insel Riems on the occasion of its 100th anniversary. 相似文献