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11.
The angiopoietin (Ang) family of proteins are central to the regulation of angiogenesis. The purposes of this study were to determine cDNA sequences of canine Ang-1 and Ang-2 and investigate their expressions in normal tissues and spontaneous tumours. The cDNA sequences of canine Ang-1 and Ang-2 were 1,494 and 1,488 bp, and the deduced amino acid sequences were 497 and 495 residues, respectively. The cDNA sequences of canine Ang-1 and Ang-2 showed high homology with those of the other mammalian species. Canine Ang-1 and Ang-2 mRNA were detectable in all 22 normal tissues and spontaneous tumours. Higher mRNA expression level of canine Ang-2 was demonstrated in mammary simple carcinomas, haemangiosarcoma and hepatocellular carcinoma in comparison with normal tissues.  相似文献   
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To understand the viscoelasticity of wood three dimensionally, matched samples of Japanese cypress were loaded in uniaxial tensile creep in the longitudinal (L), radial (R), and tangential (T) directions at approximately 9.7 % equilibrium moisture content. Longitudinal and transverse strains were measured for the determination of viscoelastic Poisson’s ratios and three-dimensional viscoelastic compliance tensors concerning the normal strain. The changes in the transverse strains showed the same tendencies as those in the longitudinal strains, in all directions of loading. That is, during creep, the absolute value of transverse strain continued to increase with the gradual reduction in the increase rate; immediately after the removal of the load, it recovered rapidly, after which it continued to recover slowly. The transverse strain increased most easily in the T direction, followed by R and L, during creep. All the viscoelastic Poisson’s ratios and the absolute values of all elements of the viscoelastic compliance increased logarithmically with creep time. The three-dimensional viscoelastic compliance matrix for Japanese cypress is concluded to be asymmetric.  相似文献   
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Meteorite studies suggest that each solar system object has a unique oxygen isotopic composition. Chondrites, the most primitive of meteorites, have been believed to be derived from asteroids, but oxygen isotopic compositions of asteroids themselves have not been established. We measured, using secondary ion mass spectrometry, oxygen isotopic compositions of rock particles from asteroid 25143 Itokawa returned by the Hayabusa spacecraft. Compositions of the particles are depleted in (16)O relative to terrestrial materials and indicate that Itokawa, an S-type asteroid, is one of the sources of the LL or L group of equilibrated ordinary chondrites. This is a direct oxygen-isotope link between chondrites and their parent asteroid.  相似文献   
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We compared the biological properties of Oshima 5-10 (tick-borne encephalitis [TBE] virus isolated in Hokkaido, Japan) and Sofjin-HO (Far-Eastern subtype TBE virus) including plaque formation, virus replication and virus protein synthesis in BHK-21 cell cultures to reveal strain differences. We also determined the complete nucleotide sequences of both strains and compared the deduced amino acid sequences. Plaques of Oshima 5-10 were smaller than those of Sofjin-HO. Virus titers in culture fluid of Oshima 5-10 were 1/100 of those of Sofjin-HO at 9 and 12 hr after infection. Less viral protein and RNA syntheses of strain Oshima 5-10 was observed than with Sofjin-HO. Genetic analysis revealed 1.4% of amino acids to differ with Sofjin-HO. No difference between the two strains was detected in the motif sequence of the viral enzyme, cleavage sites of viral protein or glycosylation sites of NS1.  相似文献   
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Dried egg white protein was heated at 120°C for 1 hr, added to a fresh wheat flour (protein 8.6%), and the protein and wheat flour were subjected to acetic acid (pH 3.5) fractionation. The results showed that egg white protein increased the binding between prime starch (PS) and tailings (T) fractions in wheat flour. Several conditions for heating of egg white protein were examined to determine 1) the effect of the amount of water added to the protein before heating; 2) the effect of heating time (hr) on protein at 120°C; and 3) the effect of heating temperature on the binding between PS and T fractions. The amount of protein per 50.0 g of wheat flour was further examined for the maximum binding between PS and T fractions. The heated egg white protein was analyzed by Fourier transform infrared (FT‐IR) spectroscopy, and the changes in the secondary structures (α‐helix, β‐sheets, and others) of the protein caused by heating were studied. When egg white protein was heated at 120°C for 8 hr, 9.0% of the α‐helix structures of egg white protein decreased to 3.0%, and 37.0% of the β‐sheet structures increased to 41.0%. The decrease of α‐helix and increase of β‐sheet structures of heated egg white protein were related to the increase in the binding between PS and T fractions in the same heated egg white protein and wheat flour sample. A relationship between the structural changes in heated egg white protein (180°C, 1 hr) and the binding between PS and T fractions in the heated egg white protein and wheat flour was also observed.  相似文献   
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The present study was conducted to demonstrate the spindle formation and behavior of chromosomes and microtubules during first division in reconstructed rat embryos produced by somatic cell nuclear transfer (SCNT) with cumulus cell nuclei. To demonstrate the effect of oocyte aging after ovulation on the cleavage of SCNT embryos, micromanipulation was carried out 11, 15 and 18 h after injection of hCG. SCNT oocytes were activated by incubation in culture medium supplemented with 5 microM ionomycin for 5 min followed by treatment with 2 mM 6-dimethylaminopurine (6-DMAP) in mR1ECM for 2-3 h. For immunocytochemical observation, the SCNT embryos were incubated with monoclonal anti-alpha-tubulin antibody and then fluorescein isothiocyanate (FITC)-conjugated goat anti-mouse IgG. Cleavage rates were significantly higher for oocytes collected after 15 and 18 h rather than for those collected 11 h after injection of hCG (56 and 53%, respectively vs. 28%; P<0.05). Premature chromosome condensation occurred before activation of the SCNT oocytes, but adequate spindle formation was only rarely observed. The distribution of microtubules in SCNT embryos after activation was different from those of fertilized and parthenogenic oocytes, i.e., a dense microtubule organization shaped like a ring was observed. Eighteen to 20 h post-activation, most SCNT embryos were in the 2-cell stage, but no nucleoli were clearly visible, which was quite different from the fertilized oocytes. In addition, first division with and without small cellular bodies containing DNA was observed in the rat SCNT embryos in some cases. The present study suggests that reorganization of transferred nuclei in rat SCNT embryos may be inadequate in terms of formation of the mitotic assembly and nucleolar reorganization.  相似文献   
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Glimepiride and nateglinide are two common oral hypoglycemic agents currently being used with humans suffering from Type 2 diabetes mellitus. Neither drug has been tested with cats thus far and it is currently unknown whether either of these drugs exert any effect in cats or not. The objective of this study was to determine the effect of glimepiride and nateglinide on glucose and insulin responses in healthy control cats, in order to determine their potential use in diabetic cats. The intravenous glucose tolerance tests was carried out since it is an excellent test for evaluating pancreatic β-cell function for insulin secretion. Alterations in the insulin secretion pattern can be perceived as the earliest sign of β-cell dysfunction in many species, including cats. Nateglinide demonstrated a quick action/short duration type effect with serum glucose nadiring and insulin response peaking at 60 and 20 minutes, respectively. Alternatively, glimepiride is medium-to-long acting with serum glucose nadiring and insulin response peaking at 180 minutes and 60 minutes, respectively. Nateglinide’s potency was evident allowing it to induce a 1.5–2 higher preliminary insulin peak (3.7?±?1.1 pg/ml) than glimepiride’s (2.5?±?0.1 pg/ml), albeit only for a short period of time. Because glimepiride and nateglinide have a shared mode of action, no significant differences in overall glucose AUC0-360min (24,435?±?2,940 versus 24,782?±?2,354 mg min/dl) and insulin AUC0-360min (410?±?192 versus 460?±?159) in healthy control cats were observed. These findings may provide useful information when choosing a hypoglycemic drug suited for the treatment of diabetic cats depending on the degree of diabetes mellitus the cat is suffering from.  相似文献   
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