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161.
The Bovine Parainfluenza-3 (PI-3) virus was isolated and identified from an aborted bovine fetus. The fetal isolate was characterized and found to be similar to the respiratory isolate. Inutero inoculations of bovine fetuses with the PI-3 fetal isolate established fetal pathogenicity, and fetal immune competency. Inoculation of pregnant immune heifers and ewes failed to demonstrate transplacental transmission of virus. Sera from 1500 cows were examined for the presence of PI-3 serum neutralizing (SN) antibody. All serum samples contained PI-3 SN antibody at the 1:2 dilution and greater. Since PI-3 seropositive animals resist transplacental transmission of virus, and since seronegative animals are rarely available, the Bovine Parainfluenza-3 virus is probably not a common cause of fetal disease and abortion in Wyoming.  相似文献   
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Summary Many new technologies arrived at through basic research have practical applications. Two recent breakthroughs in microbiology, recombinant DNA techniques and hybridoma techniques, will permit designing cells for specific practical purposes resulting in new products or functions of commercial significance. The unique cell or its usefulness, or both, may satisfy the requirements of a patentable invention, i.e. an inventive act having utility and novelty. Ownership of such patents permits recovery of expenses incurred in the invention process and investment for all concerned in additional research. An integral part of the patenting process is submission of the new cell to an official repository, an outstanding example of which is The American Type Culture Collection.  相似文献   
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The conserved 3'-terminal stem-loop (3' SL) of the West Nile virus (WNV) genomic RNA was previously used to probe for cellular proteins that may be involved in flavivirus replication and three cellular proteins were detected that specifically interact with the WNV 3' SL RNA (J. L. Blackwell and M. A. Brinton, J. Virol. 69:5650-5658, 1995). In this study, one of these cellular proteins was purified to apparent homogeneity by ammonium sulfate precipitation and liquid chromatography. Amino acid sequence Western blotting, and supershift analyses identified the cellular protein as translation elongation factor-1 alpha (EF-1 alpha). Competition gel mobility shift assays demonstrated that the interaction between EF-1 alpha and WNV 3' SL RNA was specific. Dephosphorylation of EF-1 alpha by calf intestinal alkaline phosphatase inhibited its binding to WNV 3' SL RNA. The apparent equilibrium dissociation constant for the interaction between EF-1 alpha and WNV 3' SL RNA was calculated to be 1.1 x 10(-9) M. Calculation of the stoichiometry of the interaction indicated that one molecule of EF-1 alpha binds to each molecule of WNV 3' SL RNA. Using RNase footprinting and nitrocellulose filter binding assays, we detected a high-activity binding site on the main stem of the WNV 3' SL RNA. Interaction with EF-1 alpha at the high-activity binding site was sequence specific, since nucleotide substitution in this region reduced the binding activity of the WNV 3' SL RNA for EF-1 alpha by approximately 60%. Two low-activity binding sites were also detected, and each accounted for approximately 15 to 20% of the binding activity. Intracellular association between the host protein and the viral RNA was suggested by coimmunoprecipitation of WNV genomic RNA and EF-1 alpha, using an anti-EF-1 alpha antibody.  相似文献   
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