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961.
962.
Molly I. Keating 《Tropical animal health and production》1987,19(3):147-152
Dioxathion residues in milk (expressed as the sum of the cis and trans isomers) have been determined by gas liquid chromatography using the N-P thermionic detector. It was found that dioxathion residues of 0.06 to 2.29 ppm (fat basis) are present in milk and are associated with tick control procedures of spraying cows with 0.05% w/v dioxathion (Delnav) twice weekly. Average concentrations from bulked milk were 0.96 ppm after 10 hours, 0.54 ppm after 34 hours and 0.4 ppm after 58 hours following spraying. The levels of residues in the milk differed greatly in different animals. 相似文献
963.
Rhesus monkey fetuses of either immune or nonimmune dams were inoculated in utero with Adenovirus SV-20 (AdSV-20), a virus capable of inducing fetal pneumonia, and studied immunologically at various intervals. AdSV-20 infection at 90–100 days gestational age resulted in absolute lymphopenia in a few fetuses, reduced numbers of peripheral blood lymphocytes (PBL) which formed rosettes with sheep erythrocytes (ERL) and reduced complement-receptor lymphocytes (CRL) in a majority, while Fc fragment-receptor lymphocytes (FcRL) were occasionally increased. There was a tendency for depression of ERL and CRL early in infection of 120–130-day fetuses, followed by stimulation of these populations and FcRL in later phases. Maternal immunity did not protect against these effects of AdSV-20 infection in fetuses. Immune and nonimmune dams were spared adverse clinical effects and had no changes in lymphoid cell populations following inoculation of their fetuses.Despite precocious production of circulating IgM, fetuses of nonimmune dams had little or no demonstrable anti-AdSV-20 serum neutralizing (SN) antibody, indicating that the ability to develop an effective immune response was suppressed or had not been acquired at the gestational ages studied. Nonimmune dams displayed little evidence of seroconversion following inoculation of their fetuses with AdSV-20, except in those dams whose fetuses died in utero, whereby there was a significant antibody response. SN antibody titers of immune dams were not boostered substantially subsequent to inoculation of their fetuses, and fetal SN titers were lower than maternal titers, suggesting absence of an active fetal antibody response in this group also. Direct inoculation of AdSV-20 into 90–130-day rhesus monkey fetuses provided a model system for immunologic study of fetal infection, probably involving complex fetal-maternal interactions, in a situation where the infected, viable fetus and its dam appeared to be microbiologically isolated from one another. 相似文献
964.
Development of PCR-based tests for the identification of North American isolates of epizootic haemorrhagic disease virus. 总被引:2,自引:0,他引:2 下载免费PDF全文
A serogroup-specific polymerase chain reaction (PCR) assay and isolate identification strategies (restriction endonuclease analysis (REA) and nucleotide sequencing) were developed for the detection of North American isolates of epizootic haemorrhagic disease virus (EHDV). PCR primers (EHDV-pr4, EHDV-pr5) were designed to hybridize to the L3 gene of a North American isolate of EHDV serotype 1. Total nucleic acid was extracted from preparations of infected tissue culture and PCR was performed using a cDNA-PCR kit, according to the manufacturer's specifications. The PCR assay generated a 459 base pair product from North American isolates of EHDV serotypes 1 and 2, while bluetongue virus (BTV) serotypes 10, 11, 13, and 17, and cell controls, failed to demonstrate PCR products. Slight modifications allowed for the PCR detection of EHDV-1 and -2 in white-tailed deer blood (Odocoileus virginiatus); PCR fragments were not amplified from uninfected deer blood. A number of restriction endonucleases and sequencing primers were evaluated for their utility in isolate identification experiments. Specifically, REA employing HincII and cycle sequencing with an internal primer (EHDV-1-pr3) proved most successful for identifying isolate-specific genome markers. The techniques presented are expected to prove valuable for rapid and specific detection of possible future EHDV incursions in wild and domestic animal species. 相似文献
965.
S Kouider F E Kolb I Müller C Pfüller J Schneider 《Archiv fuer experimentelle veterinaermedizin》1977,31(5):701-718
Horses were examined for the behaviour of various blood constituents prior to and following infusions of solutions of glucose, fructose, invertose, and sorbitol. Infusion of 0.5 g/kg live weight glucose to six horses was followed by half-life variation between eleven and 23 minutes. Subsequent infusion of invertose to the same animals usually caused prolongation of glucose half-life. Half-life values were between 17 and 33 minutes for fructose and between 21 and 80 minutes for glucose. Infusion of 0.5 g/kg live weight fructose to two horses was followed by half-life values between 17 and 18 minutes, while the half-life values of sugar alcohol were 16, 16, 27, and 29 minutes in four horses who had received sorbitol. Sugar or sorbitol infusion was not followed by substantive change of lactate and pyruvate concentrations in the blood or free fatty acids in the blood plasma or GOT activity. The rise of insulin in the blood plasma was differentiated. Invertose and sorbitol solutions, consequently, can be recommended for application to horses. 相似文献
966.
Contrary to expectation, immunoconglutinin levels failed to rise significantly in calves infected with Trypanosoma congolense. In addition, it was shown that trypanosome infection appeared to inhibit the immunoconglutinin response to Brucella abortus strain 19. The possible reasons for these findings are discussed. 相似文献
967.
Teratogenic effects of methylparathion / Wofatox 50 EC/ and Parathion 20 WP as positive control material were tested in pheasant embryos. On the 12th day of incubation 0.1 ml of the emulsions or suspensions of the insecticides at different concentrations was inoculated into the air space of embryonated eggs. The following dose levels were employed: 27 and 270 mg/kg egg of Wofatox 50 EC, and 10 mg/kg of Parathion 20 WP. Morphological changes were evaluated by macroscopic, skeletal staining and light microscopic examinations of the embryos. Primary hypoplasia or atrophy developed in the cervical musculature /m. longus colli/ accompanied by lordosis and scoliosis of the cervical spine. In most cases we also found cyllosis . 相似文献
968.
969.
970.