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81.
YOSHIRO WATANABE HIROMU ZENITANI RYO KIMURA CHIKAKO SATO YUTAKA OKUMURA HIROYA SUGISAKI & YOSHIOKI OOZEKI 《Fisheries Oceanography》1998,7(2):101-109
Naupliar copepods were distributed at similar concentrations over the waters inshore and offshore of the Kuroshio Current off central Japan in early spring 1993 and 1994, overlapping with the distribution of early feeding larvae of Sardinops melanostictus . Although N, P, Si and chlorophyll a concentrations were higher in the waters inshore of the Kuroshio axis than in the offshore waters, the mean concentrations of nauplii were not statistically different between the two waters. Food availability for larval S. melanostictus did not seem to be different between the two waters in terms of the mean food concentrations. Using the critical food concentration (>9 nauplii L–1 ) for 25% survival during 3 days after first feeding derived from a rearing experiment, percentages in number of stations or water samples with nauplii concentrations >9 nauplii L–1 were higher in the inshore waters than in the offshore waters in both years examined. Considering that fish larvae may depend on small-scale patchiness of food for their survival, the inshore waters seemed to be more favourable for first-feeding larvae than the offshore waters. 相似文献
82.
Wataru Yamamoto 《Journal of Forest Research》2000,5(3):195-199
Natural forest in Sri Lanka has been decreased significantly in the last few decades. The remaining natural forests especially
in floristic region seven have undergone less conservation efforts in the past. Considering the capacity of the government
and dependence on forest resources by local villagers, the only way for conservation of these forests in the Southwest lowland
is forest management through local participation. Management plans for community-based resource management have been completed.
However promotion of such management requires integrated measures, which are beyond jurisdiction of Forest Department. A holistic
approach with political commitment concerning buffer zone villages and economic incentives with income generation opportunities
supported by external inputs are expected to be implemented as a matter of urgency. 相似文献
83.
Hiroshi OKAMOTO Mamoru SATO Yoshio MIYATA Masami YOSHIKAWA Makoto ISAKA 《Journal of General Plant Pathology》2000,66(1):86-94
Bacterial strains isolated from the rhizosphere of angelica trees were evaluated for their antagonistic activity against Phytophthora cactorum, a causal agent of Phytophthora root rot. Of these, three bacterial strains, designated as T-1-8, T-1-14 and T-1-23, strongly inhibited mycelial growth of
P. cactorum ARE-862 in a dual-culture plate assay. Biocontrol activity of these strains was then examined by dipping root of young seedlings
of angelica trees into a bacterial suspension. The incidence of Phytophthora root rot was markedly suppressed for at least 79 days in pot tests when treated seedlings were planted in naturally infested
soil. The suppression was maintained through June of the next year. In addition, these strains significantly reduced the development
of Phytophthora root rot up to 47 days in naturally infested field and up to 63 days (the last day of testing) in an artificially (moderately)
infested field. Based on their main bacteriological properties, strain T-1-14 was identified as Enterobacter cloacae and T-1-8 and T-1-23 were identified as Serratia ficaria.
Received 5 July 1999/ Accepted in revised form 25 October 1999 相似文献
84.
Shun TAKEO Daichi SATO Koji KIMURA Yasunori MONJI Takehito KUWAYAMA Ryoka KAWAHARA-MIKI Hisataka IWATA 《The Journal of reproduction and development》2014,60(2):92-99
The aim of the present study was to address the effect of resveratrol-mediated
upregulation of sirtuin 1 (SIRT1) during oocyte maturation on mitochondrial function, the
developmental ability of oocytes and on mechanisms responsible for blockage of polyspermic
fertilization. Oocytes collected from slaughterhouse-derived ovaries were cultured in
TCM-199 medium supplemented with 10% FCS and 0 or 20 µM resveratrol (Res). We examined the
effect of Res on SIRT1 expression in in vitro-matured oocytes (Exp 1);
fertilization and developmental ability (Exp 2); mitochondrial DNA copy number (Mt
number), ATP content and mitochondrial membrane potential in matured oocytes (Exp 3); and
the time required for proteinase to dissolve the zona pellucida following in
vitro fertilization (as a marker of zona pellucida hardening), as well as on
the distribution of cortical granules before and after fertilization (Exp 4). In Exp 1,
the 20 µM Res treatment upregulated protein expression of SIRT1 in oocytes. In Exp 2, Res
treatment improved the ratio of normal fertilization and the total cell number of
blastocysts. In Exp 3, Res treatment significantly increased the ATP content in matured
oocytes. Additionally, Res increased the overall Mt number and mitochondrial membrane
potential, but the effect was donor-dependent. In Exp 4, Res-induced zona hardening
improved the distribution and exocytosis of cortical granules after in
vitro fertilization. In conclusion, Res improved the quality of oocytes by
improving mitochondrial quantity and quality. In addition, Res added to the maturation
medium enhanced SIRT1 protein expression in oocytes and improved fertilization via
reinforcement of the mechanisms responsible for blockage of polyspermic fertilization. 相似文献
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