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991.
992.
993.
Pregnant rats were given daily a subcutaneous injection of methyltestosterone for 4 days from the 17th to the 20th day of gestation, and were allowed to be delivered to their offsprings (F1) which were used for the examination of later reproductive functioning. When observed for 21 weeks after birth, the growth rate of F1 from methyltestosterone-treated groups was higher than that of F1 from the control group. The anogenital distance in 50-microgram-treated F1 females started to become significantly longer on the 14th day and in 5-microgram-treated F1 females on the 28th day after birth than that in F1 from the control. The day on which vaginal opening took place in 50% of females was 34.4 days of age in both the control and the 5 microgram groups, but it delayed until 40.7 days in the 50 microgram group. Furthermore, persistent estrus was observed after about 90 days of age in the 50 microgram group. This persistent estrus disappeared by placing these females with males, resulting no pregnancy. In the 5 microgram group females could be pregnant, but their female fetuses (F2), when examined on the 21st day of gestation, had significantly shortened the length of the urovaginal septum. The observations show that virilization can be induced in the third generation. 相似文献
994.
Alcohol oxidases of Kloeckera sp. and Hansenula polymorpha. Catalytic properties and subunit structures. 总被引:5,自引:0,他引:5
1. Alcohol oxidase (alcohol: oxygen oxidoreductase) of a thermophilic methanol-utilizing yeast, Hansenula polymorpha DL-1, was isolated in crystalline form. 2. This alcohol oxidase of H. polymorpha was more stable to heat than was the enzyme of Kloeckera sp. This difference in heat stability is compatible with the difference in growth temperatures for both yeasts. 3. The crystalline alcohol oxidases of both yeast oxidized the lower primary alcohols (C-2 to C-4) as well as methanol. The apparent Km values for the methanol of Kloeckera and H. polymorpha enzymes were 0.44 and 0.23 mM, respectively. The enzymes could also oxidize formaldehyde to formate, and were inactivated by relatively low concentrations of hydrogen peroxide. 4. The molecular weight for both enzymes was calculated to be about 670000. Each enzyme is composed of eight identical subunits (molecular weight 83000) and contains eight moles of FAD as the prosthetic group. The NH2-terminal and COOH-terminal amino acids of H. polymorpha enzyme were identified as alanine and phenylalanine, respectively. The octameric subunits model of each enzyme was confirmed by electron micrographs, which showed an octad aggregate, composed of two tetragons face to face. 相似文献
995.
H Kurogi Y Inaba Y Tanaka Y Ito K Sato T Omori 《National Institute of Animal Health quarterly》1976,16(2):39-48
A cytopathogenic virus was isolated in the primary culture of bovine kidney cells from a nasal swab of affected calves in an outbreak of acute respiratory disease in Japan in 1971. It agglutinated human type O erythrocytes and produced cytoplasmic inclusion bodies. Viral replication was inhibited by 5-iodo-2'-deoxyuridine, indicating that the viral nucleic acid was RNA. The virus was resistant to ether, chloroform, sodium deoxycholate, and acid, and passed readily through Sartorius' membrane filter 100 nm in pore size, but not through the filter 50 nm in pore size. Electron microscopy showed many spherical particles 60 approximately 75 nm in diameter with a double-layered capsid in a sample taken at a buoyant density of 1.34 produced by CaCl equilibrium centrifugation. The virus suspended in 1M MgCl2 solution was stable against heating at 50 degrees C for 30 minutes, but not against freezing at -20 degrees C for 60 minutes. The virus was resistant to, and increased in infectivity after, treatment with 0.063 approximately 1.0% trypsin. These properties were consistent with those established for the reoviruses. Most affected cattle showed a significant rise of antibody titer against reovirus and bovine respiratory syncytial virus, whereas only a few of them presented a serological evidence for recent infection with parainfluenza virus type 3, bovine adenovirus type 7, and bovine parovirus. 相似文献
996.
H Kurogi Y Inaba E Takahashi K Sato T Omori 《National Institute of Animal Health quarterly》1976,16(2):49-58
In April, 1971, a disease with pyrexia and diarrhea as main symptoms broke out collectively among calves. Fecal samples were collected from calves involved and inoculated into bovine kidney (BK) cell cultures. As a result, the diarrheal feces of one calf were suspected to contain two agents simultaneously. One agent (C-121 E strain) was isolated from the primary infected BK cell culture fluid by terminal dilution passages. It had been predominant in replication and shown a cytopathic effect which gave rise to a granular appearance in the early stage of culture. The other agent (C-121 R strain) was isolated from the primary infected BK cell culture fluid by neutralizing the C-121 E strain contained in this fluid with antiserum against this strain. It caused cytoplasmic inclusion bodies to form. On the basis of their physico-chemical properties, the C-121 E strain was identified as bovine enterovirus and the C-121 R strain as reovirus. Serological tests indicated that some of the affected calves had been infected not only with the two strains isolated, but also with bovine viral diarrhea virus, bovine adenovirus type 7, and bovine parvovirus. 相似文献
997.
Yuko Kaneko Takehiko Saito 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1992,170(4):411-425
Summary Electrical membrane properties of solitary spiking cells during newt (Cynops pyrrhogaster) retinal regeneration were studied with whole-cell patch-clamp methods in comparison with those in the normal retina.The membrane currents of normal spiking cells consisted of 5 components: inward Na+ and Ca++ currents and 3 outward K+ currents of tetraethylammonium (TEA)-sensitive, 4-aminopyridine (4-AP)-sensitive, and Ca++-activated varieties. The resting potential was about -40mV. The activation voltage for Na+ and Ca++ currents was about -30 and -17 mV, respectively. The maximum Na+ and Ca++ currents were about 1057 and 179 pA, respectively.In regenerating retinae after 19–20 days of surgery, solitary cells with depigmented cytoplasm showed slowrising action potentials of long duration. The ionic dependence of this activity displayed two voltage-dependent components: slow inward Na+ and TEA-sensitive outward K+ currents. The maximum inward current (about 156 pA) was much smaller than that of the control. There was no indication of an inward Ca++ current.During subsequent regeneration, the inward Ca++ current appeared in most spiking cells, and the magnitude of the inward Na+, Ca++, and outward K+ currents all increased. By 30 days of regeneration, the electrical activities of spiking cells became identical to those in the normal retina. No significant difference in the resting potential and the activation voltage for Na+ and Ca++ currents was found during the regenerating period examined. 相似文献
998.
Isolation and characterization of cDNA clones encoding cdc2 homologues from Oryza sativa: a functional homologue and cognate variants. 总被引:10,自引:0,他引:10
Junji Hashimoto Toshio Hirabayashi Yuriko Hayano Shingo Hata Yuko Ohashi Iwao Suzuka Takahiko Utsugi Akio Toh-E Yoshiko Kikuchi 《Molecular & general genetics : MGG》1992,233(1-2):10-16
Summary Using probes obtained by PCR amplification, we have isolated two cognate rice cDNAs (cdc2Os-1 andcdc2Os-2) encoding structural homologues of thecdc2
+/CDC28(cdc2) protein kinase from a cDNA library prepared from cultured rice cells. Comparison of the deduced amino acid sequences of cdc2Os-1 and cdc2Os-2 showed that they are 83 % identical. They are 62 % identical toCDC28 ofSaccharomyces cerevisiae and much more similar to the yeast and mammalian p34cdc2 kinases than to riceR2, acdc2-related kinase isolated previously by screening the same rice cDNA library with a different oligonucleotide probe. Southern blot analysis indicated that the three rice clones (cdc2Os-1,cdc2Os-2 andR2) are derived from distinct genes and are each found in a single copy per rice haploid genome. RNA blot analysis revealed that these genes are expressed in proliferating rice cells and in young rice seedlings.cdc2Os-1 could complement a temperature-sensitive yeast mutant ofcdc28. However, despite the similarity in structure, bothcdc2Os-2 andR2 were unable to complement the same mutant. Thus, the present results demonstrate the presence of structurally related, but functionally distinct cognates of thecdc2 cell cycle kinase in rice.The nucleotide sequence data in this paper have been deposited in the EMBL database under accession number X60374 (cdc2Os-1) and X60375 (cdc2Os-2) 相似文献
999.
Masahiro Ishigami Masataka Kinjo Kei Nagano Yuko Hattori 《Origins of life and evolution of the biosphere》1982,12(3):307-310
Protein and non-protein amino acids were synthesized following hydrolysis of products obtained by high frequency discharge techniques applied to model atmospheres consisting of N2 as a nitrogen source together with CH4 and/or CO2 as a carbon source. Highest yields were obtained in the absence of CO2 and from mixtures rich in CH4. Amino acids would indeed be expected on the frozen surface of Titan with its CH4–N2 atmosphere.Paper presented at the 6th College Park Colloquium, October 1981. 相似文献
1000.
Visual deprivation of the chicken eye causes axial elongation with high myopia. The cartilaginous layer of the myopic sclera shows an increase of mitotic activity. Previous studies reported that the in vivo administration of apomorphine, a dopamine nonselective agonist, effectively prevents visual-deprivation myopia. Because the retinal pigment epithelium (RPE) regulates growth of the sclera as we and others have shown previously, it is speculated that the RPE cells may play an important role in this preventive effect of apomorphine. In this study, to clarify the mechanism by which the administration of apomorphine inhibits the proliferation of scleral chondrocytes in vivo, we have investigated the effect of apomorphine on the proliferation of scleral chondrocytes with or without co-cultured RPE cells in vitro. We previously demonstrated that cell proliferation of scleral chondrocytes remarkably increases with co-cultured RPE cells. In this study, we found that apomorphine at concentrations of higher than 2×10−5 M dramatically reduced the growth-stimulatory effect of RPE cells on the scleral chondrocytes, whereas the inhibitory effect of apomorphine on the proliferation of scleral chondrocytes without RPE cells was very little. Our results strongly suggest that apomorphine may reduce the production and/or release of some humoral factors from RPE cells, which stimulate the growth of scleral cells. There is also a possibility that apomorphine reduces the reactivity of scleral cells to the humoral factors released from RPE cells. © 1997 John Wiley & Sons, Ltd. 相似文献