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41.
Kuniyoshi Shimizu Shoko Fukunaga Keisuke Yoshikawa Ryuichiro Kondo 《Journal of Wood Science》2007,53(2):153-160
The effects of 120 methanol extracts prepared from bark and heartwood of 69 types of Japanese wood on the melanin production
of B16 melanoma cells were examined. The melanin content of B16 melanoma cells was determined spectrophotometrically at 405nm.
The extracts were also examined for their effects on cell viability. We found that the methanol extracts of Fagus crenata (buna, wood, 100μg/ml), Sapium sebiferum (Nankinhaze, wood, bark, 10μg/ml), and Zelkova serrata (keyaki, wood, 10μg/ml) greatly inhibited the melanin production of B16 melanoma cells without significant cytotoxicity.
However, these extracts did not inhibit tyrosinase activity at the concentration of 100μg/ml. These findings indicate that
the depigmenting mechanism of these extracts involves the suppression of some pigmenting signals in stimulating melanogenesis
rather than the inhibition of tyrosinase activity.
Part of this study was presented at the 53rd Annual Meeting of the Japan Wood Research Society, Fukuoka, Japan, March 2003 相似文献
42.
Tsutomu Suzuki Kyoko Suzuki Yukio Takahashi Mitsuhiro Okimoto Tetsuo Yamada Noriyasu Okazaki Yuichi Shimizu Masashi Fujiwara 《Journal of Wood Science》2007,53(1):54-60
Japanese larch wood loaded with nickel (1%–4%) alone or with nickel and calcium (0.25%–1.5%) was carbonized at 800°–900°C
for 0–120min with a heating rate of 5°–20°C min−1 in a helium flow of 5.8−46.4 ml STP cm−2 min−1 to examine the influence of these variables on the crystallization of carbon (the formation of T component) and the development
of mesoporosity. From the obtained results, reaction conditions suitable for effective production of carbon with the dual
functions of adequate electroconductivity and adsorption capacity in liquid phase were established, thereby explaining the
factors that govern the process. It was also confirmed that mesopore having a diameter of about 4 nm was selectively produced
at the cost of specific (BET) surface area in parallel with the formation of T component. This result provided good insight
into how the simultaneous dual function could be realized. 相似文献
43.
Tadahisa MASHITA Hiroaki KAMISHINA Yuya NAKAMOTO Yosuke AKAGI Ataru NAKANISHI Yusuke HARASAKI Tsuyoshi OZAWA Takashi UEMURA Yui KOBATAKE Shunsuke SHIMAMURA Naoki KITAMURA Sadatoshi MAEDA Yuji UZUKA Gerry SHAW Jun YASUDA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(4):433-438
The aim of this study was to evaluate the prognostic value of concurrent measurement of
serum phosphorylated neurofilament heavy subunit (pNF-H) concentration and intramedullary
T2W hyperintensity in paraplegic to paraplegic dogs. Our hypothesis was that concurrent
measurement of these would provide a more accurate prediction of functional outcome in
dogs with thoracolumbar intervertebral disc herniation (IVDH). A prospective case-control
clinical study was designed using 94 dogs with acute onset of thoracolumbar IVDH. The
association of serum pNF-H concentration, T2W hyperintensity on sagittal MRI (T2H/L2),
deep pain perception and surgical outcome were evaluated with logistic regression analysis
after three months for all 94 surgically treated dogs. Sensitivity to predict
non-ambulatory outcome was compared among pNF-H and T2H/L2 and combination of both.
Logistic regression analysis indicated that serum pNF-H concentration and T2H/L2 were
significantly correlated with surgical outcome (P<0.05); however, deep
pain perception was not (P=0.41). The results of logistic regression
analysis indicated that the odds ratios of unsuccessful long-term outcome were 2.6 for
serum pNF-H concentration, 1.9 for T2H/L2 and 2.3 for deep pain sensation. The sensitivity
and specificity to predict non-ambulatory outcome for using serum parameter pNF-H>2.6
ng/ml, using T2H/L2 value of>0.84 and using both
serum pNF-H and T2H/L2, were 95% and 75.7%, 65% and 86.5%, and 90.0% and 97.5%,
respectively. Therefore, combined measurements of serum pNF-H and T2H/L2 might be useful
for predicting long-term outcome in dogs with thoracolumbar IVDH. 相似文献
44.
Rukmali ATHURUPANA Daisen TAKAHASHI Sumire IOKI Hiroaki FUNAHASHI 《The Journal of reproduction and development》2015,61(3):205-210
Cryopreservation of boar semen is still considered suboptimal due to lower fertility as compared with fresh samples when glycerol, a permeating cryoprotectant, is used. Trehalose is a non-permeable cryoprotectant and nonreducing disaccharide known to stabilize proteins and biologic membranes. The aim of this study was to evaluate the cryosurvival and in vitro penetrability of boar spermatozoa when glycerol was replaced with trehalose in a freezing extender. Ejaculated Berkshire semen samples were diluted in egg yolk-based freezing extender containing glycerol (100 mM) or trehalose (0, 50, 100, 150, 200 and 250 mM) and cryopreserved using a straw freezing procedure. Thawed samples were analyzed for motility, viability, mitochondrial membrane potential (MMP), and acrosome integrity. In experiment 2, penetrability of spermatozoa cryopreserved with 100 mM glycerol or trehalose was examined. Replacement of cryoprotectant glycerol (100 mM) with trehalose had no
effect on sperm viability, but replacing it with 100 mM trehalose improved motility, MMP and acrosome integrity significantly. Sperm motility and MMP were considerably higher in 100 mM trehalose, whereas the acrosome integrity was substantially higher in 100–250 mM trehalose. The in vitro penetration rate was also significantly higher in spermatozoa cryopreserved with trehalose (61.3%) than in those cryopreserved with glycerol (43.6%). In conclusion, 100 mM non-permeable trehalose can be used to replace glycerol, a permeating cryoprotectant, for maintenance of better post-thaw quality of boar spermatozoa. 相似文献
45.
46.
Masaaki Katayama Yasuhiko Okamura Shunsuke Shimamura Rieko Katayama Hiroaki Kamishina Yuji Uzuka 《Research in veterinary science》2014
Graft perfusion with cold heparinized saline has known to induce ischemia and reperfusion injury in feline kidney transplantation. In this study, the effects of phosphate-buffered sucrose solution and heparinized saline solution on early kidney graft function were compared in feline kidney autotransplantation. Perfusion of grafts with or without hypothermic storage with chilled phosphate-buffered sucrose solution prevented ischemia and reperfusion injury despite a very short ischemic time. The results of our study suggest that phosphate-buffered sucrose perfusion and storage solution should be effective to reduce ischemia and reperfusion injury despite a very short ischemic time in feline kidney transplantation. 相似文献
47.
In this study, the expressions of VEGF in dog follicles were detected by immunohistochemistry and the effects of VEGF treatment on the primordial to primary follicle transition and on subsequent follicle progression were examined using a dog ovary organ culture system. The frozen‐thawed canine ovarian follicles within slices of ovarian cortical tissue were cultured for 7 and 14 days in presence or absence of VEGF. After culture, the ovaries were fixed, sectioned, stained and counted for morphologic analysis. The results showed that VEGF was expressed in the theca cells of antral follicles and in the granulosa cells nearest the oocyte in preantral follicle but not in granulosa cells of primordial and primary follicles; however, the VEGF protein was expressed in CL. After in vitro culture, VEGF caused a decrease in the number of primordial follicles and concomitant increase in the number of primary follicles that showed growth initiation and reached the secondary and preantral stages of development after 7 and 14 days. Follicular viability was also improved in the presence of VEGF after 7 and 14 days in culture. In conclusion, treatment with VEGF was found to promote the activation of primordial follicle development that could provide an alternative approach to stimulate early follicle development in dogs. 相似文献
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