خيارات البحث
النتائج 61 - 70 من 489
Characterization of the chicken PKR: Polymorphism of the gene and antiviral activity against vesicular stomatitis virus
2004
Ko, J.H. (Hokkaido Univ., Sapporo (Japan)) | Asano, A. | Kon, Y. | Watanabe, T. | Agui, T.
Comparison of virulence of various hantaviruses related to hemorrhagic fever with renal syndrome in newborn mouse model
2004
Lokugamage, K. (Hokkaido Univ., Sapporo (Japan)) | Kariwa, H. | Lokugamage,N. | Iwasa, M. | Hagiya, T. | Araki, K. | Tachi, A. | Mizutani, T. | Yashimatsu, K. | Arikawa, J. | Iwasaki, T. | Takashima, I.
Follicular development after ovum pick-up and fertilizability of retrieved oocytes in postpartum dairy cattle
2004
Sasamoto, Y. (Hokkaido Univ., Sapporo (Japan)) | Sakaguchi, M. | Nagano, M. | Katagiri, S. | Takahashi, Y.
Effects of oxygen tension in the gas atmosphere during in vitro maturation, in vitro fertilization and in vitro culture on the efficiency of in vitro production of mouse embryos
2004
Adam, A.A.G. (Hokkaido Univ., Sapporo (Japan)) | Takahashi, Y. | Katagiri, S. | Nagano, M.
Effects of oxygen (O2) tension in the gas atmosphere during in vitro maturation (IVM), in vitro fertilization (IVF) and in vitro culture (IVC) on the efficiency of in vitro production of mouse embryos were examined. Mouse oocytes recovered from large antral follicles were subjected to IVM in Waymouth medium for 15, 16 and 17 hr under 5 or 20% O2 and then subjected to IVF and IVC under 5 or 20% O2 tension. Lowering the O2 tension in the gas atmosphere for IVM from 20 to 5% improved the cleavage rate after IVF when the oocytes were subjected to IVM for 15 hr; however, no improvement in the cleavage rate was observed when the culture period for IVM was extended to 16 and 17 hr. Lowering the O2 tension to 5% for IVM and IVC improved the development of the cleaved oocytes to the blastocyst stage, regardless of the culture period for IVM. However, the O2 tension for IVF had no remarkable effect on the subsequent embryonic development. These results demonstrate that 5% O2 is superior to 20% O2 for IVM and IVC, and suggest that 20% O2 for IVM may delay oocyte maturation and/or the acquisition of fertilizability and impair the developmental competence of oocytes.
اظهر المزيد [+] اقل [-]Iodine intake as a possible cause of discontinuous decline in sperm counts: A re-evaluation of historical and geographic variation in semen quality
2004
Sakamoto, K.Q. (Hokkaido Univ., Sapporo (Japan)) | Ishizuka, M. | Kazusaka, A. | Fujita, S.
In order to examine whether iodine supplements may have caused a global decline in sperm concentrations during the past several decades, the synchronicity of the decline in mean sperm counts and the introduction of io-dine supplements was analyzed statistically. A positive correlation between the incidence of thyroid disease and sperm counts has been detected in Europe. In addition, it has been shown that sperm counts began falling around 1965 in the United States, 40years after iodine supplements were introduced. Mean sperm counts before and after 1965 were 111 10 sup(6)/ml and 70 10 sup(6)/ml, respec-tively, in calculations weighted by the number of subjects included in each in-dividual publication. The timing of the declines coincided with the introduc-tion of iodine supplements in the United States, France, and the United King-dom. The implications are that the global decline in sperm concentrations may be caused by iodine intake. Geographical variation in the types of sperm count decline also appears to be present.
اظهر المزيد [+] اقل [-]Adrenocortical responses to tumor necrosis factor-alpha and interferon-gamma in cattle
2004
Soliman, M. (Hokkaido Univ., Sapporo (Japan)) | Okamoto, S. | Kitamura, H. | Kushibiki, S. | Kimura, K. | Saito, M.
The responses of plasma cortisol and adrenocorticotropic hormone (ACTH) were examined to intravenous injection of recombinant bovine tumor necrosis factor-alpha (TNF-alpha) and interferon-y (INF-gama) in Holstein cows. INF-gamain-duced dose-dependent rises in the plasma levels of both cortisol and ACTH, while TNF-alpha induced comparable plasma cortisol responses with much smaller rises in plasma ACTH. The results suggest a direct stimulatory action of TNF-alpha on cortisol secretion from the adrenal gland in cattle.
اظهر المزيد [+] اقل [-]Distribution of neutral amino acid transporter ASCT1 in the non-neuronal tissues of mice
2004
Hashimoto, Y. (Hokkaido Univ., Sapporo (Japan)) | Sadamoto, Y. | Konno, A. | Kon, Y. | Iwanaga, T.
Distribution of ASCT1, a neutral amino acid transporter, in non-neuronal peripheral tissues of adult and developing mice was examined by immunohis- tochemistry and immunoelectron microscopy. Immunoreactivity for ASCT1 in the digestive system was localized in basal cells of stratified squamous epithe-lia from oral parietes to nonglandular region of the stomach, chief cells of the glandular stomach, acinar cells of the salivary gland and exocrine pancreas, and Paneths cells of the small intestine, in all of which the basolateral mem-brane was selectively immuno-labeled. In the liver of adult mice, ASCT1 immunoreactivity was detected on the plasma membrane of hepatocytes sur-rounding central veins, and a temporal expansion of immunoreactive hepato-cytes was observed in the embryonic and CCI sub(4)-treated adult livers. ASCT1 was also localized on the plasma membranes of proximal uriniferous tubule epithelial cells in the kidney of adult mice, and those of supporting cells in the medulla of adrenal gland. These results suggest that ASCT1 is expressed in various non-neuronal peripheral tissues in mice, and it contributes to the amino acid transport throughout non-neuronal tissues.
اظهر المزيد [+] اقل [-]Evidence for bovine immunodeficiency virus infection in cattle in Zambia
2004
Meas, S. (Hokkaido Univ., Sapporo (Japan)) | Nakayama, M. | Usui, T. | Nakazato, Y. | Yasuda, J. | Ohashi, K. | Onuma, M.
Psittacine beak and feather disease virus in budgerigars and ring-neck parakeets in South Africa
2004
Albertyn, J. | Tajbhai, K.M. | Bragg, R.R. (Free State Univ., Bloemfontein (South Africa). Microbial, Biochemical and Food Biotechnology Dept.)
A laboratory comparison of the life cycles of the dog ticks Haemaphysalis leachi and Rhipicephalus sanguineus
2004
Jacobs, P.A.H. | Fourie, L.J. | Horak, I.G. (Free State Univ., Bloemfontein (South Africa). Zoology and Entomology Dept.)