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Nahoko Kurachi Tomiyasu Miyaura Jumpei Toriyama Yojiro Matsuura Akira Osawa 《Scandinavian Journal of Forest Research》2019,34(2):102-114
We estimated the aboveground net primary production (ANPP) in five self-thinning jack pine (Pinus banksiana) stands in Wood Buffalo National Park, NWT, Canada. The stands (11 to ca.175 years old) were selected to examine the relationship between stand density and tree size and its effect on carbon dynamics. Aboveground litterfall was collected from each stand from 1997 to 2012. Stand biomass was estimated by measuring tree size every 5 years and estimating the individual mass using allometric relationships. ANPP was then estimated by summing the litterfall mass, dead stem mass increment and stand biomass increment. We determined the proportional contribution of each organ to the total litter and the seasonal pattern of needle litterfall. There was a lower turnover rate of aboveground biomass in older stands than younger stands. The ANPP increased in the youngest stand (<30 years old) showed a decreasing trend in stands >50 years old. The maximum ANPP was estimated to be ca. 500?g m?2 year?1 in dry matter, which was found in 30–50 year-old stands. 相似文献
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Randomized clinical trial to evaluate the effectiveness of enrofloxacin as a second‐line antibiotic for treatment of acute Escherichia coli mastitis 下载免费PDF全文
Kazuhiro Kawai Akira Takeda Michiaki Yamada Fumi Kayasaki Nao Kondo Yoshiko Sasaki Nahoko Kanai Takuma Mukai Naoki Sawaguchi Masaya Higuchi Haruka Kondo Kouki Sugimoto Akane Yasuda Aiko Watanabe 《Animal Science Journal》2018,89(7):1033-1039
The objective of the present study was to evaluate the effectiveness of enrofloxacin (ERFX) as a second‐line antibiotic for treatment of acute Escherichia coli (E. coli) mastitis. Forty‐two cows with naturally occurring acute E. coli mastitis were enrolled. On the first day of treatment (day 0), empirically selected antibiotics (oxytetracycline: n = 32, kanamycin: n = 10) were administered. Although systemic signs improved in 10 cows (first‐line group), the signs remained unchanged or worsened in 32 cows on day 1, including two cows that were found dead. The 30 surviving cows were randomly assigned to second‐line groups constituting an ERFX group (n = 19) or a control group (n = 11) that was treated with other antibiotics. Response to each treatment was evaluated by measuring clinical signs from day 0 to day 3, subsequent quarter milk recovery, and the 60‐day survival rate. Appetite on day 3 was significantly better in the ERFX group compared to the control group. No significant differences were observed in the 60‐day survival rate or the subsequent milk recovery between the ERFX group and the control group. Thus, the use of ERFX as a second‐line antibiotic for the treatment of acute E. coli mastitis could induce a rapid appetite recovery. 相似文献
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Fujinami N Hosoi Y Kato H Matsumoto K Saeki K Iritani A 《The Journal of reproduction and development》2004,50(2):171-178
Developmental potential of bovine embryos that are not artificially activated after intracytoplasmic sperm injection (ICSI) is generally very low. In this study, we investigated effects of artificial activation with ethanol on kinetics of maturation promoting factor (MPF) activity (p34(cdc2) kinase activity) and development of bovine oocytes following ICSI. Treatment of oocytes with ethanol at 4 h after ICSI improved their first cleavage and further preimplantation development (51% vs. 13%, 14% vs. 4%: treatment with vs. without ethanol, respectively). MPF activity of oocytes was lowered until at least 2 h after ICSI. In oocytes without activation after ICSI, MPF activity temporarily elevated at 6 h after ICSI, whereas this phenomena was not observed in the oocytes treated with ethanol. Furthermore, MPF activity was elevated 20 h after ICSI in oocytes activated with ethanol, whereas this elevation of MPF activity was not shown in oocytes without activation. These results indicate that the stimulus of sperm was sufficient to lower MPF activity of oocytes following ICSI, and moreover the activation treatment of bovine oocytes with ethanol after ICSI served to maintain the low levels of MPF activity until the next cell cycle started. 相似文献
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Mst. Parvin MOSTARI Nahoko IEDA Chikaya DEURA Shiori MINABE Shunji YAMADA Yoshihisa UENOYAMA Kei-ichiro MAEDA Hiroko TSUKAMURA 《The Journal of reproduction and development》2013,59(3):266-272
Accumulating evidence suggests that the arcuate nucleus (ARC) kisspeptin/neurokinin B
(NKB)/dynorphin (KNDy) neurons play a role in estrogen negative feedback action on
pulsatile gonadotropin-releasing hormone (GnRH)/luteinizing hormone (LH) release. The
present study aimed to determine if dynorphin (Dyn) is involved in estrogen negative
feedback on pulsatile GnRH/LH release. The effect of the injection of nor-binaltorphimine
(nor-BNI), a kappa-opioid receptor (KOR) antagonist, into the third cerebroventricle (3V)
on LH pulses was determined in ovariectomized (OVX) adult female rats with/without
replacement of negative feedback levels of estradiol (low E2). The mean LH
concentrations and baseline levels of LH secretion in nor-BNI-injected, low
E2-treated rats were significantly higher compared with vehicle-treated
controls. On the other hand, the nor-BNI treatment failed to affect any LH pulse
parameters in OVX rats without low E2 treatment. These results suggest that Dyn
is involved in the estrogen negative feedback regulation of pulsatile GnRH/LH release. The
low E2 treatment had no significant effect on the numbers of ARC
Pdyn (Dyn gene)-,Kiss1- and
Tac2 (NKB gene)-expressing cells. The treatment also did not affect
mRNA levels of Pdyn and Oprk1 (KOR gene) in the
ARC-median eminence region, but significantly increased the ARC kisspeptin
immunoreactivity. These findings suggest that the negative feedback level of estrogen
suppresses kisspeptin release from the ARC KNDy neurons through an unknown mechanism
without affecting the Dyn and KOR expressions in the ARC. Taken together, the present
result suggests that Dyn-KOR signaling is a part of estrogen negative feedback action on
GnRH/LH pulses by reducing the kisspeptin release in female rats. 相似文献
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Nahoko IEDA Yoshihisa UENOYAMA Yoko TAJIMA Tomoko NAKATA Masatoshi KANO Yousuke NANIWA Youki WATANABE Shiori MINABE Junko TOMIKAWA Naoko INOUE Fuko MATSUDA Satoshi OHKURA Kei-ichiro MAEDA Hiroko TSUKAMURA 《The Journal of reproduction and development》2014,60(4):312-316
Puberty is associated with an increase in gonadotropin secretion as a result of an increase in gonadotropin-releasing hormone
(GnRH) secretion. Kisspeptin is considered to play a key role in puberty onset in many mammalian species, including rodents,
ruminants and primates. The present study aimed to determine if changes in hypothalamic expression of the KISS1
gene, encoding kisspeptin, are associated with the onset of puberty in pigs. The animals (n=4 in each group) were perfused with 4%
paraformaldehyde at 0, 1, 2, 3 and 4 months old, as prepubertal stages, and at 5 months old, as the peripubertal stage, following
each blood sampling. KISS1 gene expressions in coronal sections of brains were visualized by in
situ hybridization. Plasma luteinizing hormone (LH) was measured by radioimmunoassay. KISS1 mRNA
signals were observed in the arcuate nucleus (ARC) at all ages examined without any significant difference in the number of
KISS1-expressing cells, indicating that the KISS1 gene is constantly expressed in the ARC
throughout pubertal development in pigs. The plasma LH concentration was the highest in 0-month-old piglets and significantly
decreased in the 1- and 2 month-old groups (P<0.05), suggesting a developing negative feedback mechanism affecting gonadotropin
release during the prepubertal period. Considering the potent stimulating effect of kisspeptin on gonadotropin release in
prepubertal pigs, kisspeptin secretion rather than kisspeptin synthesis may be responsible for the onset of puberty in pigs. 相似文献
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Nahoko Nishi Tatsuro Muta Yoko Ito Masayuki Nakamura Takao Tsukiboshi 《Journal of General Plant Pathology》2009,75(1):80-82
A new disease of chrysanthemum causing ray speck was found in Okinoerabu island, Kagoshima, Japan in March 2006. Small reddish-brown
lesions were observed on the ray florets of the chrysanthemum (cv. Anastasia). The causal fungus was exclusively isolated
from the lesions, and typical symptoms were reproduced after inoculation with the isolate. The causal fungus was identified
as Stemphylium lycopersici (Enjoji) Yamamoto based on morphology and the sequences of rDNA-ITS and the gpd gene regions. The name, “sho-hanten-byo”, in Japanese is proposed for this ray speck disease. 相似文献
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Reiichiro Sato Tetsuo Ito Tsunenori Suganuma Yumi Une Tomoo Kudo Hideki Kayanuma Eiichi Kanai Takehito Suzuki Hideharu Ochiai Nahoko Enomoto Seigo Itoh Ken Onda Yasunori Wada 《The Canadian veterinary journal. La revue veterinaire canadienne》2015,56(5):463-465
A male crossbred calf developed a limp and pain upon deep pressure on the right hind limb and the right forelimb. The radiographic findings of affected limbs and pathological findings of bone biopsy were similar to those observed in canine panosteitis. This is the first case of suspected panosteitis reported in cattle. 相似文献
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