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排序方式: 共有1574条查询结果,搜索用时 281 毫秒
41.
ABSTRACT: This study assessed the stock-recruitment relationship (SRR) for the Japanese sardine Sardinops melanostictus in the North-western Pacific. Of the 20 SRR models investigated, the Akaike information criterion (AIC) was the minimum (AIC = 551.2) when the data were separated into two groups (A and B) and the log-normal distribution was applied as the error term. Group A was constructed with SRR data from 1976–1987 and 1992–2004. Group B consisted of data from 1988–1991. The AIC minimum model was R = 22.8 S × e ε for Group A, where R , S , and ε denote the recruitment of sardine (individual number of 0-year old fish), spawning stock biomass (SSB), and error term, respectively. This model indicated that recruitment was proportional to the SSB and that no density-dependent effect operated over the range of SSB investigated (51 000–11.3 million t). Recruitment was markedly higher (lower) when the sea surface temperature (SST) of the Kuroshio Extension area in February was low (high). The essential SRR can simply be expressed as R = 22.8 S × e ε with the level of recruitment deviating from the model to a greater or lesser degree depending on the environmental conditions. 相似文献
42.
Purification and characterization of two anionic trypsins from the hepatopancreas of carp 总被引:8,自引:0,他引:8
Min-Jie Cao Kiyoshi Osatomi Miho Suzuki Kenji Hara Katsuyasu Tachibana and Tadashi Ishihara 《Fisheries Science》2000,66(6):1172-1179
SUMMARY: Two trypsins, designated as trypsin A and trypsin B, have been purified from the hepatopancreas of carp. The purification procedures consisted of ammonium sulfate fractionation, and chromatographies on DEAE-Sephacel, Ultrogel AcA54 and Q-Sepharose. Trypsin A was purified to homogeneity with the molecular mass of approximately 28 kDa, while trypsin B gave two close bands of 28.5 kDa and 28 kDa on sodium dodecylsulfate polyacrylamide gel electrophoresis both under reducing and non-reducing conditions. On native-PAGE, both trypsin A and trypsin B showed a single band. Trypsin A and trypsin B revealed optimum temperature of 40°C and 45°C, respectively, and shared the same optimum pH 9.0 using Boc-Phe-Ser-Arg-MCA as substrate. Both enzymes were effectively inhibited by trypsin inhibitors and their susceptibilities were similar. The NH2 -terminal amino acid sequences of trypsin A and trypsin B were determined to 37th and 40th amino acid residue, respectively. Their sequences were very homologous, but not identical to that of a trypsin-type serine proteinase from carp muscle and these of other trypsins. Immunoblotting test using the antibody raised against trypsin A cross-reacted with trypsin B positively. 相似文献
43.
Y. Takazawa T. Nishino Y. Sasaki H. Yamashita N. Suzuki K. Tanabe Y. Shibata 《Water, air, and soil pollution》2009,202(1-4):57-67
Comprehensive survey of major rivers in the Tokyo metropolitan area was conducted for clarifying the emission sources of perfluorooctane sulfonate (PFOS) in Tokyo. PFOS was found at all sampling sites at concentrations ranging from 0.5 to 58 ng L?1; in addition to this, it was also indicated that unknown PFOS emission sources are present in the midstream of the Tama River basin. The relationship between PFOS and perfluorooctanoic acid (PFOA) was constant at a ratio of 10:3 (PFOS/PFOA) throughout the Tama River basin. The sum of daily load amounts of PFOS from Tokyo’s major rivers to Tokyo Bay reached 215 g day?1. This value corresponds to 12.8 μg day?1 per person using the sum of wastewater treatment district populations. In contrast, an estimation of PFOS contribution of domestic wastewater was also attempted, and the contribution was 1.6 μg day?1 per person. We took samples up trunk sewers in the Tama River and finally found at the highest PFOS concentration (58,000 ng L?1) from one of the wastewater of the electronic parts manufacturing facilities. 相似文献
44.
Evaluating the durability of wood-based panels using internal bond strength results from accelerated aging treatments 总被引:1,自引:0,他引:1
In this study, the durability of wood-based panels was evaluated by comparing the internal bond (IB) strength retention after
five different laboratory-based accelerated aging tests with the IB retention after 5 years of outdoor exposure in Shizuoka
City. In each accelerated aging test, the IB retention of MDI-bonded panels showed high retention compared to other panels.
Outdoor exposure in Shizuoka City resulted in an IB retention value for particleboard (PF) and oriented strandboard (aspen)
of less than 10% after the 5-year exposure period. Medium-density fiberboards maintained their initial IB strength over the
same period. Calculation of the mean IB retention for all board types allowed comparison of the severity of aging between
the accelerated test methods and outdoor exposure. The ASTM six-cycle test method was the most severe among the standard treatment
cycles applied. 相似文献
45.
Shinya Kasajima Chidori Katagiri Toshikazu Morishita Tatsuro Suzuki Yuji Mukasa 《Plant Production Science》2017,20(4):384-388
Common buckwheat is a self-incompatible, insect-pollinated allogamous plant. This study examined growth and yield of the common buckwheat self-compatible and hybrid lines pollinated with and without flies. Self-compatible ‘IH3’, hybrid ‘IP2/IH3’, and standard self-incompatible ‘Kitawasesoba’ were used in field and pot experiments. Self-compatibility of ‘IH3’ was shown to be of high purity. Approximately 10% segregation of pin plants from ‘IP2/IH3’ was observed. The harvest index of ‘Kitawasesoba’ pollinated without flies was considerably lower than that pollinated with flies in both field and pot experiments. The harvest index values of ‘IH3’ and ‘IP2/IH3’ were hardly affected by the presence or absence of flies. The morphological traits of ‘IH3’ were significantly lower than those of the other two genotypes. Large differences in these traits between ‘IP2/IH3’ and ‘Kitawasesoba’ were not observed in either the field or pot experiments. The seed yield of ‘Kitawasesoba’ pollinated without flies tended to be lower than that pollinated with flies. The seed yield of ‘IP2/IH3’ tended to be higher than that of ‘IH3’. The hybrid line ‘IP2/IH3’ showed a high fertilization rate, which was nearly as high as that of ‘IH3’. Rate of fertilization and percentage of ripe seeds were higher in ‘IH3’ and ‘IP2/IH3’, wherein they were hardly affected by the presence or absence of flies, than in ‘Kitawasesoba’. The ‘IP2/IH3’ hybrid line will be useful for understanding the stable high-yielding ability of self-compatibility common buckwheat. 相似文献
46.
Loida O. Casalme Keisuke Katayama Yoshiki Hayakawa Kensuke Nakamura Arisa Yamauchi Yasuyuki Nogata Erina Yoshimura Fuyuhiko Matsuda Taiki Umezawa 《Marine drugs》2022,20(2)
Some derivatives of dolastatin 16, a depsipeptide natural product first obtained from the sea hare Dolabella auricularia, were synthesized through second-generation synthesis of two unusual amino acids, dolaphenvaline and dolamethylleuine. The second-generation synthesis enabled derivatizations such as functionalization of the aromatic ring in dolaphenvaline. The derivatives of fragments and whole structures were evaluated for antifouling activity against the cypris larvae of Amphibalanus amphitrite. Small fragments inhibited the settlement of the cypris larvae at potent to moderate concentrations (EC50 = 0.60-4.62 μg/mL), although dolastatin 16 with a substituent on the aromatic ring (24) was much less potent than dolastatin 16. 相似文献
47.
Suzuki J Miwa N Kumazaki K Abe M Kamanaka Y Matsubayashi N Gotoh S Matsubayashi K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2001,63(4):361-366
To clarify the influence of rearing conditions on the growth of various body parts of Japanese macaques (Macaca fuscata), two groups reared under different conditions, i.e., a group born and reared in open enclosures (Enclosure group) and another consisting of macaques born and reared in cages (Caged group), were somatometrically analyzed. Somatometric data on 36 measures of various body parts were collected from 77 males and 92 females. Growth in many body parts was smaller in the Caged group than in the Enclosure group. Body parts that exhibited large incremental increases were more sensitive to differences in rearing space at the infantile growth stage in both sexes. Recovery from delayed growth at the pubertal growth stage was found in many body parts. However, the size of some locomotor elements such as the wrist and hand, and ankle and foot strongly reflected limitations of space and changes due to this were irreversible. Females were more sensitive than males to such differences in rearing conditions. We conclude that open enclosures with ample rearing space are necessary for the innate growth of Japanese macaques to occur. 相似文献
48.
Yabuki A Maeda M Suzuki S Matsumoto M Kurohmaru M Hayashi Y Taniguchi K Nishinakagawa H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2001,63(4):461-465
Although mice kidney morphology shows various sexual dimorphisms, the effect of the estrous cycle has not previously been discussed. In this study, we investigated the effects of the estrous cycle on kidney morphology, including renin-positive areas, of female DBA/2 mice. No effects were confirmed in most of the histometrical parameters, however, the percentage of the renal corpuscles in which cuboidal epithelium covered under 50% of the parietal layer was significantly higher during estrus compared to that during anestrus. 相似文献
49.
50.
Seiji TSUGE Ayako FURUTANI Rie FUKUNAKA Yasuyuki KUBO Osamu HORINO 《Journal of General Plant Pathology》2001,67(1):51-57
Xanthomonas oryzae pv. oryzae (X. o. pv. oryzae) T7174 is virulent on rice cultivar IR24 and avirulent on IR-BB2. From recent reports, some virulence and avirulence factors
of plant pathogenic bacteria are transferred to plant cells through the hrp-dependent type III secretion system. In this study, we investigated the involvement of hrp genes in the compatible and the incompatible interactions between rice and X. o. pv. oryzae after co-inoculation with hrpXo mutants derived from T7174 and virulent strains. Growth of the mutants, named 74ΔHrpXo and 76ΔHrpXo, was repressed in IR24 when the mutants were applied alone. However, growth of the mutants was complemented by co-inoculation
with virulent strains. Growth of bioluminescent hrpXo mutant 76ΔHrpXo in IR24 and its growth in IR-BB2 after co-inoculation with T7133, which is virulent on both cultivars, was equally complemented,
as detected by bioluminescence from the mutant. On the other hand, only partial complementation of growth of T7174L76, which
is a bioluminescent and pathogenic derivative of T7174, by T7133 was observed in IR-BB2. Thus, growth of the hrpXo mutant of X. o. pv. oryzae was complemented by virulent strains in both susceptible and resistant rice leaves with the parental strain.
Received 21 July 2000/ Accepted in revised form 26 October 2000 相似文献