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21.
The reference strains of four serotypes (J6, J8, J9 and J10) of porcine enterovirus isolated in Japan were compared with the international reference strains of 11 serotypes (W1 to W11) by cross neutralization tests. No cross reactions were observed between the two groups, although there were minor one-way crosses between W10 and J10, W11 and J9, and W4 and J9. This leads to our conclusion that all 4 Japanese serotypes can be newly added to 11 international serotypes. J9 virus produced type 1 of CPE (CPE I), J6 and J8 did CPE II, and J10 did CPE III. J10 grew in Vero, HeLa cells, and the primate cells, but J6, J8 and J9 did not.  相似文献   
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23.
The enantiomeric compositions of 2-methylbutanol (1), 4-methylhexanol (2), 2-methylbutanoic acid (3), and 4-methylhexanoic acid (4) present in rhubarb (Rheum rhabarbarum L.) stalks were determined. Enantiodifferentiation was achieved via multidimensional gas chromatography using heptakis(2,3,6-tri-O-ethyl)-beta-cyclodextrin as a chiral stationary phase. For all compounds the enantiomeric ratios were in favor of the (R)-enantiomers. The alcohols (1 and 2) exhibited generally high excesses of the (R)-enantiomers, the ratios varying slightly from batch to batch. For the acid (3) a rather narrow range averaging 65% (R):35% (S) was observed. The procedure applied to isolate the volatiles (vacuum headspace technique, simultaneous distillation--extraction, liquid--liquid extraction) had no significant impact on the enantiomeric ratios. The study describes for the first time a plant used as food material in which 2-methyl-branched volatiles are not nearly exclusively present as (S)-enantiomers. This information enlarges the current regulatory knowledge regarding the classification of these important flavor compounds as "natural" on the basis of their enantiomeric ratios.  相似文献   
24.
The impact cratering process on a comet is controversial but holds the key for interpreting observations of the Deep Impact collision with comet 9P/Tempel 1. Mid-infrared data from the Cooled Mid-Infrared Camera and Spectrometer (COMICS) of the Subaru Telescope indicate that the large-scale dust plume ejected by the impact contained a large mass (approximately 10(6) kilograms) of dust and formed two wings approximately +/-45 degrees from the symmetric center, both consistent with gravity as the primary control on the impact and its immediate aftermath. The dust distribution in the inner part of the plume, however, is inconsistent with a pure gravity control and implies that evaporation and expansion of volatiles accelerated dust.  相似文献   
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26.
The ability of the whitefly Bemisia tabaci to transmit two strains of Tomato yellow leaf curl virus, the Israel and Mild strains, was studied after serial transfers of individual whiteflies that were viruliferous for both strains to tomato plants. After single whiteflies had successive acquisition feedings first on a single plant infected with one strain and then on a plant infected with the other strain, the single whiteflies later transmitted intermittently one, the other, or both strains to the test plants during serial transfers at 1-day intervals. Because both strains were found in the head, abdomen, and legs dissected from whiteflies during the retention period after the two successive acquisition feedings, both strains apparently circulate from midgut cells to salivary glands through the hemolymph.  相似文献   
27.
Nineteen monoclonal antibodies (MAbs), reactive in enzyme-linked immunosorbent assay (ELISA), with porcine transmissible gastroenteritis (TGE) virus TO-163 were obtained. Of these MAbs, 5 showed neutralizing (NT) activity (x 3,200 to 25,600) against TO-163. One of the MAbs which had NT activity showed hemagglutination inhibition activity (x 5,120) too. 14 hybridomas of polypeptide specificity against TO-163 strain were developed from which 11, 2, and 1 were specific for protein E2, N, and E1, respectively. Immunofluorescence staining patterns in TGE virus-infected cells reacted with MAbs were divided into three groups (types I, II and III). The fluorescence staining of E2 specific MAbs having NT activity were limited to the perinuclear area. All MAbs having NT activity showed the same fluorescence staining pattern.  相似文献   
28.
The antibody response of rabbit to infectious bovine rhinotracheitis (IBR) virus was examined. Two rabbits were inoculated with IBR virus strain Los Angeles into the trachea and intravenously, and intravenously two times, respectively. The patterns of antibody titers in the rabbits measured by neutralization test and ELISA were similar to those in the case of bovine. The antibody was detected after the inoculation, and much more antibody was detected after the second inoculation. The fact suggests that rabbits are a very useful laboratory animal for IBR virus infection studies.  相似文献   
29.
The safety and efficacy of the cell-associated (C-A) vaccine prepared by chicken embryo fibroblast (CEF) cells infected with the tissue-culture-modified strain of infectious laryngotracheitis (ILT) virus were studied in chickens. Over seventy percent of chickens inoculated with the C-A vaccine by the subcutaneous (S.C.) or intramuscular (I.M.) route at 1 day of age was protected against challenge with a virulent strain of ILT virus without any clinical signs. Chickens vaccinated with the C-A vaccine at 1 day of age acquired immunity within 6 days after vaccination, and the protection rate maintained more than 60% until 10 weeks post-vaccination. The C-A vaccine was invariably effective for chickens at various age. There was no evidence that the development of immunity was hindered by further vaccination with Newcastle disease and infectious bronchitis combined live vaccine. In addition, the C-A vaccine was safe when chickens were inoculated with 10 doses. In the field trials of the C-A vaccine, no adverse reaction was observed, and over 65% of vaccinated chickens was protected against the challenge of the virulent ILT virus at 8 weeks after vaccination.  相似文献   
30.
The pathogenicity and immunogenicity of vaccinia virus were examined in order to evaluate the possibility of its application as a recombinant viral vaccine in pigs. Following scarification inoculation with vaccinia virus, a mild reddish papulation developed only on the scarified part of the skin. No symptoms of illness such as fever or stunting were noted. Vaccinia virus was recovered in titers from scarified skin 4 and 7 days after inoculation. Control piglets cohabited with inoculated animals remained normal for the whole 5 week observation period. Hemagglutination inhibition and indirect immunofluorescence tests detected antibodies against vaccinia virus in the inoculated piglets, whereas no anti-vaccinia virus antibodies were detected in the contact control animals. Antigen-induced blastogenic tests of peripheral blood lymphocytes from animals, revealed that lymphocytes obtained from inoculated donors 5 weeks after inoculation, had a higher stimulation index (P less than 0.05) than did those from uninoculated piglets. These results suggested that vaccinia virus would be useful as a recombinant viral vector for pigs.  相似文献   
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