Уточнить поиск
Результаты 111-120 из 271
Effects of concurrent exposure to 3-methylcholanthrene and vitamin A on fetal development in rats
1999
Khlood, El.B.M. (Hokkaido Univ., Sapporo (Japan)) | Miyoshi, H. | Iwata, H. | Kazusaka, A. | Kon, Y. | Hadid, A.H.A. | Moustafe, El.K. | Ghonim, M.H. | Fujita, S.
To investigate the effect of the environmental pollutants, polycyclic aromatic hydrocarbons (PAHs), on retinoic acid-induced teratogenesis, all-trans-retinoic acid (RA) dissolved in corn oil (120 mg/kg) was administered orally to pregnant rats at the 11th day of gestation with and without the prior intraperitoneal treatment with 10 mg/kg 3-methylcholanthrene (3-MC) for 3 days. Dams were killed on the 20th day of pregnancy. The examinations of fetuses revealed that 3-MC barely enough to cause induction of P-450 in pregnant dams had profound embryo-toxic effects: the fetal resorption amounted to - 60% of total number of implantations. The fetuses survived weighed less than the control fetuses. All of RA-treated mothers had fetuses with abnormalities, and the main malformations were absence of tail (100%), caudal and sacral malformations (100%), and cleft palate (42%). Pregnant dams received both 3-MC and RA had a reduced severeness of tail anomaly (33%), while the rest, 67%, had short vestigial tail. Caudal and sacral malformations were detected but at a milder degree. We did not observe cleft palate in this group. The concurrent treatment of dams with 3-MC and RA led to an increased inducibility of cytochrome P-450 and subsequently, CYP1A1 dependent enzyme activity higher than those observed after the injection of 3-MC alone. UDP-glucuronyltransferase activity was also markedly induced in concurrent 3-MC and RA group higher than that in 3-MC alone. We suggest that the induction of P-450 and alteration of metabolic enzyme activities may play an important role in reducing the teratogenic potency of RA. However, RA-treatment did not retard the embryo-toxic effect of 3-MC but rather potentiated
Показать больше [+] Меньше [-]A comparison of serum biochemical changes in two breeds of sheep (Red Masai and Dorper) experimentally infected with Fasciola gigantica
1999
Waweru, J.G. | Kanyari, P.W.N. | Mwangi, D.M. | Ngatia, T.A. (Nairobi Univ. (Kenya). Dept. of Veterinary Pathology and Microbiology) | Nansen, P.
Confirmation that PCR can be used to identify NAD-dependent and NAD-independent Haemophilus paragallinarum isolates
1999
Miflin, J.K. (Animal Research Inst., Moorooka (Australia)) | Chen, X. | Bragg, R.R. | Welgemoed, J.M. | Greyling, J.M. | Horner, R.F. | Blackall, P.J.
Seroprevalence of infectious bursal disease in non-vaccinated indigenous and exotic chickens on selected farms around Gaborone, Botswana
1999
Mushi, E.Z. (Botswana College of Agriculture, Gaborone (Botswana)) | Binta, M.G. | Chabo, R.G. | Ndebele, R.T.
Copper poisoning in wild ruminants in the Kruger National Park [South Africa]: Geobotanical and environmental investigation
1999
Grobler, D.G. (Pretoria Univ., Onderstepoort (South Africa). Dept. of Pharmacology and Toxicology)
The occurence of Theileria and Cowdria parasites in African buffalo (Syncerus caffer) and their associated Amblyomma hebraeum ticks
1999
Allsopp, M.T.E.P. (Agricultural Research Council, Onderstepoort (South Africa). Onderstepoort Veterianry Inst.) | Theron, J. | Coetzee, M.L. | Dunsterville, M.T. | Allsopp, B.A.
Experimental studies with Strongyloides papillosus in goats
1999
Pienaar, J.G. (Regional Veterinary Laboratory, Potgietersrus (South Africa)) | Basson, P.A. | Du Plessis, J.L. | Collins, H.M. | Naude, T.W. | Boyazoglu, P.A. | Boomker, J. | Reyers, F. | Pienaar, W.L.
A serological survey of bovine babesiosis in northern and eastern Zimbabwe
1999
Katsande, T.C. (Central Veterinary Laboratory, Harare (Zimbabwe)) | More, S.J. | Bock, R.E. | Mabikacheche, L. | Molloy, J.B. | Ncube, C.
Evaluation of conventional odour attractants for Glossina brevipalpis and Glossina austeni (Diptera: Glossinidae) in South Africa
1999
Kappmeier, K. | Nevill, E.M. (Agricultural Research Council, Onderstepoort (South Africa). Onderstepoort Veterinary Inst.)
Attempted induction of chronic copper poisoning in boma confined impala
1999
Grobler, D.G. (Kruger National Park, Skukuza (South Africa). Research and Development) | Swan, G.E.
