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71.
Yuko TAJIMA Kaori MAEDA Tadasu K. YAMADA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(1):45-51
One hundred and twenty
stranding events of Stejneger’s beaked whales were reported in Japan between 1999 and
2011. The purpose of this study is to introduce pathological data and to discuss probable
causes of death for 44 Stejneger’s beaked whales among them. The significant pathological
findings were the pulmonary edema, parasitic granulomatous nephritis, emaciation,
amyloidosis, suppurative bronchopneumonia and so on. The probable causes of death were
categorized as noninfectious in 43 of the cases, which included drowning, starvation and
secondary amyloidosis. One individual was diagnosed with septicemia, which was the only
example of an infectious disease. Because we could not always perform advanced analyses,
such as microbiology tests, biotoxin examinations or contaminant analyses, the finality of
our findings may be impaired. However, the present study has broad implications on the
causes of death of Stejneger’s beaked whales of the seas around Japan, which are valuable
for the future studies and for the detection of emerging diseases. 相似文献
72.
Kikumi OGIHARA Ken ONDA Reiichiro SATO Yuko NAYA Hideharu OCHIAI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(1):85-88
L-type amino acid transporter
1 (LAT1), the first isotype of amino acid transport system L, transports aromatic and
branched amino acids pivotal for fundamental cellular activities such cellular growth and
proliferation. LAT1 expression was high only in the brain in contrast to its limited
distribution and low level of expression in normal tissues. We found potent LAT1
expression in canine caput epididymis by quantitative RT-PCR and Western blotting
analysis. Immnuno-histochemical examination revealed observable LAT1 in microvillous
epithelial cells. 相似文献
73.
Hajime ASADA Hirotaka TOMIYASU Yuko GOTO-KOSHINO Yasuhito FUJINO Koichi OHNO Hajime TSUJIMOTO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(6):677-684
Canine histiocytic sarcoma (HS) is an aggressive tumor type originating from histiocytic
cell lineages. This disease is characterized by poor response to chemotherapy and short
survival time. Therefore, it is of critical importance to identify and develop effective
antitumor drugs against HS. The objectives of this study were to examine the drug
sensitivities of 10 antitumor drugs. Using a real-time RT-PCR system, the mRNA expression
levels of 16 genes related to drug resistance in 4 canine HS cell lines established from
dogs with disseminated HS were determined and compared to 2 canine lymphoma cell lines
(B-cell and T-cell). These 4 canine HS cell lines showed sensitivities toward microtubule
inhibitors (vincristine, vinblastine and paclitaxel), comparable to those in the canine
B-cell lymphoma cell line. Moreover, it was shown that P-gp in the HS cell lines used in
this study did not have enough function to efflux its substrate. Sensitivities to
melphalan, nimustine, methotrexate, cytarabine, doxorubicin and etoposide were lower in
the 4 HS cell lines than in the 2 canine lymphoma cell lines. The data obtained in this
study using cultured cell lines could prove helpful in the developing of advanced and
effective chemotherapies for treating dogs that are suffering from HS. 相似文献
74.
75.
76.
Ring structure-reactivity relationships of three flavan-3-ols [epicatechin (EC), epicatechin gallate (ECG), and epigallocatechin gallate (EGCG)] and three simple phenolic compounds (1,3,5-trihydroxybenzene, 1,2,3-trihydroxybenzene, and methylgallate as the analogous individual A, B, and C benzene rings of EGCG) on product generation in an aqueous glucose-glycine reaction model system (125 degrees C and 30 min) were investigated. The addition of EC, ECG, or EGCG to a glucose-glycine model was reported to similarly significantly reduce the formation of pyrazine, methyl-substituted pyrazines, and cyclotene. All three flavan-3-ols were also reported to generate phenolic-C2, C3, C4, and C6 sugar fragment adducts and to statistically reduce the concentration of glyoxal, glycolaldehyde, methylglyoxal, hydroxyacetone, diacetyl, acetoin, and 3-deoxyglucosone during the reaction time course, except for the EGCG reaction where 3-deoxyglucosone was not statistically different from the control after 20 min. For the simple phenolic compounds, methylgallate followed by 1,2,3-trihydroxybenzene was the least reactive, while 1,3,5-trihydroxybenzene was reported as the most reactive phenolic structure for quenching or reducing the concentration of the alpha-hydroxy- and alpha-dicarbonyl sugar fragments during the reaction time course. These results imply that the main mechanism flavan-3-ols reduced product generation was phenolic-sugar fragment carbonyl trapping reactions primarily on the A ring (the meta-polyhydroxylated benzene ring) or not due to the alteration of the reaction reduction potential. 相似文献
77.
78.
The main objective of the present study is to investigate the molecular mechanism underlying the delay in progression of nuclear maturation in oocytes derived from cows with damaged livers (DL cows), which was previously reported. In present study, delayed progression of nuclear maturation of oocytes derived from DL cows relative to oocytes derived from cows with healthy livers (HL cows) was accompanied by low maturation promoting factor (MPF) activity (0.43 fold, p < 0.05). When cumulus cells were removed from cumulus‐oocyte complexes and the denuded oocytes were cultured, there was no difference in the progression of nuclear maturation between the two liver conditions. In addition, gap junctional communication (GJC) between the oocyte and cumulus cells was higher in DL cows than in HL cows at 3 and 7 h of in vitro maturation (IVM) (p < 0.05). Supplementation of IVM medium with epidermal growth factor (EGF) increased the ratio of germinal vesicle breakdown (GVBD) of oocytes derived from DL cows to the level seen in oocytes derived from HL cows. Additionally, the level of p38MAPK phosphorylation at 0 h of IVM was significantly lower in cumulus cells derived from DL cows than in cumulus cells derived from HL cows (HL cows, 53.5%; DL cows, 28.9%; p < 0.05). Thus, a low level of p38MAPK phosphorylation in cumulus cells induced slow GJC closure between oocyte and cumulus cells, which resulted in slow meiotic maturation of oocytes derived from DL cows. 相似文献
79.
Soichi Tanaka Keiichiro Shiraga Yuichi Ogawa Yoshihisa Fujii Shogo Okumura 《Journal of Wood Science》2014,60(2):111-116
The use of an effective medium theory is important when accurately measuring wood density using millimeter and terahertz wave techniques. To confirm the applicability of this theory to the evaluation of wood density, the relative permittivity and dielectric loss of oven-dry flat-sawn specimens of 11 different wood species were measured in a frequency range of 0.15–1.2 THz using a transmission measurement system for terahertz time-domain spectroscopy. A mixture model based on the effective medium theory well explained the density dependence of relative permittivity over the entire frequency range, while it did not fully explain that of dielectric loss, especially for higher frequencies. This indicates that wood scatters the terahertz wave with a wavelength close to the transverse sectional dimensions of the pores in wood in the same way as Mie scattering. It was found from the dielectric loss spectrum of wood substance that the frequency around 0.23 THz was preferable for the nondestructive evaluation of wood. 相似文献
80.
Soichi Tanaka Keiichiro Shiraga Yuichi Ogawa Yoshihisa Fujii Shogo Okumura 《Journal of Wood Science》2014,60(3):194-200
To clarify the effect of pore conformation on the dielectric anisotropy of wood, the relative permittivity along the longitudinal and tangential axes of flat-sawn oven-dry specimens of 12 different wood species was measured using terahertz time-domain transmission spectroscopy and compared with the values calculated using the eigenvalue problem for two-dimensional photonic crystals. The measured dielectric anisotropy, which is the ratio of the relative permittivity along longitudinal axis to that along the tangential axis, was well explained by the calculated value. It was concluded that the ratio of tangential to radial widths of wood pores affects the relative permittivity along the tangential axis, and that the dielectric anisotropy decreased with an increase in the ratio. This discussion can also be applied to the relative permittivity in frequencies below 0.15 THz. These findings show promise as a new method for evaluating the porous structure of wood. 相似文献