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1.
Yong Li Katsutaro Yamamoto Tomonori Hiraishi Katsuaki Nashimoto Hiroyuki Yoshino 《Fisheries Science》2006,72(6):1147-1152
ABSTRACT: A field experiment was conducted in the Matsumae area of Hokkaido, Japan, during June and July 2002, to investigate the effects of different entrance designs on the catch efficiency of fish traps by fishing with commercial traps (entrance inclination angle [α] = 37°; funnel length of entrance [ L f ] = 22 cm) and experimental traps. The experimental traps were of the same size and similar design as commercial traps, with different entrance inclination angles (trap E1: α = 46°; E2: α = 27°; E3: α = 0°; all L f = 22 cm) or funnel lengths (E4: α = 37°, L f = 8 cm). In total, 2200 fish during 200 trap hauls were captured. The catch was significantly higher using both traps E2 and the commercial trap than with trap E3 ( P < 0.05), and the catch of trap E2 was higher than that of the commercial trap. There were no significant differences in mean fish body length or the frequency distributions of body length among trap types (E1, E2, E3 and commercial). The funnel length of the entrance also affected the catch of traps. Trap E4 had significantly higher catches than the commercial trap ( P = 0.04) when traps were deployed for a 1-day soak time. Fish body length frequency distributions did not differ between trap E4 and the commercial trap. The results showed that catch can be greatly affected by trap entrance designs. 相似文献
2.
Norihiko Nakano Ryo Kawabe Nariharu Yamashita Tomonori Hiraishi Katsutaro Yamamoto Katsuaki Nashimoto 《Fisheries Science》2006,72(2):239-249
ABSTRACT: Color vision, spectral sensitivity, accommodation, and visual acuity were examined in juvenile masu salmon Oncorhynchus masou masou to obtain fundamental information about the visual system. Two types of S-potentials were recorded from 415 horizontal cells in isolated retinas from 34 cultured freshwater masu salmon (114–219 mm standard length, SL). Although horizontal cells recording S-potentials were not identified, the horizontal cells were confirmed because their responses were maintained while the stimulus remained. The variety of chromaticity (C)-type S-potentials indicated well-developed color vision. The analysis of the luminosity (L)-type S-potentials indicated that the peak spectral sensitivity was at 522 nm. S-potentials were also recorded in response to ultraviolet light. The direction and extent of lens movement induced by electrical stimulation was measured in 12 cultured masu salmon (99.0–142.5 mm SL). The results indicated that the visual axis was upward and forward, and that the range of accommodation was from 0.79 × SL in front of the eye to infinity. In histological analysis of the retinas of five wild smolts (100–118 mm SL), the maximum cone densities (276–345 cones/0.01 mm2 ) were detected in the ventral to temporal regions. The visual acuities assessed by histological methods were 0.069–0.075. 相似文献
3.
Katsuaki Fujinaga Anthony S Ilano Hirotaka Nomura Richard T Miranda Shigeru Nakao 《Fisheries Science》2006,72(5):995-1003
ABSTRACT: The state of imposex in Neptunea arthritica from seven sites along the coast of Hokkaido, Japan was examined in 2002 based on the criteria: (i) relative penis size index (RPSI); (ii) imposex frequency; (iii) stage frequency distribution of imposex in adult and immature whelks; and (iv) sex ratio. RPSI differed from site to site, although values from all sites were low (0.186–5.294). In particular, the RPSI values for four sites were very low (<1.0). In sites where immature whelks were also collected, the frequency of imposex was considerably lower in immature (7.7%–55.6%) than in adult whelks (50%–95.2%) except at one site. The imposex stage frequency distribution also differed among sites, and the trend in the adult whelks corresponded with their RPSI value. Female whelks showing severe imposex (Stage 3 and 3+) were restricted to large individuals. 相似文献
4.
Katsuaki Ishii 《Journal of Forest Research》2002,7(2):99-104
Hinoki cypress (Chamaecyparis obtusa) is one of the most important timber resource forest trees in Japan. Because seed production from a seed orchard of hinoki
cypress is not constant every year, micropropagation from a limited amount of material is useful. Up to now, the conventional
tissue culture method using solid medium has been used. Here a new method using liquid culture in tubes rotated vertically
is described. Shoot primordium of hinoki cypress was inoculated in Campbell and Durzan’s (CD) liquid medium containing different
cytokinins (6-benzylaminopurine (BAP), Zeatin, thidiazurone (TDZ)), and the container tubes were rotated vertically around
the axis at 2 times / min. Culture room temperature was 25°C and light condition was 16 h photoperiod per day of fluorescent
lamps. Zeatin at 1μM concentration was the best for maintaining the shoot primordium production and TDZ induced callus on the surface of the
shoot primordia. After shoot primordium multiplication in the liquid culture, they were transplanted to agar medium for shoot
elongation. A high concentration of agar (up to 16 g/L) or AVF (anti vitrification factor from Dr. Nairn, 1995) was effective
to prevent vitrification of the shoots. Transformation of shoot primordium was done using particle bombardment with vectors
containingβ-glucuronidase (GUS) gene or herbicide resistance gene (bar). Positive result for transient transformation was observed with the histo-chemical study for transformation with GUS. Integration
of a useful herbicidebar gene into the shoot primordium culture system was also tried and stably transformed plants were obtained. This is the first
report of stable transformation of Japanese conifer using practically useful gene.
The generous supply of AVF-B from Dr. B.J. Nairn, Tasman Forestry, NZ is also appreciated. 相似文献
5.
The possible horizontal transfer of transgenes is of great concern when the transgenic plants are released into the field. To test the possible transfer of nptⅡ of transgenic trees into soil bacteria, we have used a stool DNA preparation kit to isolate the DNA from the soils in the rhizospheres of two non- and eight transgenic Eucalyptus camaldulensis trees. All the samples have provided the corresponding PCR products in the amplification with bacterial 16S RNA specific sequences, which indicates that the quality of the isolated DNA is adequate for amplification. The nptⅡ specific band has been amplified in three soil samples from the transgenic trees and even treated with filtration before the DNA isolation. This indicates that nptlI DNA exists in the soil, although it is still unclear whether the DNA was in the soil particles, in the soil bacteria or in the Agrobaeterium contamination which was used for the E.camaldulensis transformation. Two approaches on isolation of bacterial DNA have been suggested for testing the possibility of this event in the future. 相似文献
6.
Toru Takeuchi Takuya KobayashiMakoto Nashimoto 《Forest Ecology and Management》2011,261(11):2089-2095
Deer expansion is a growing concern for forest ecosystem management. In Japan, upward expansion to subalpine and alpine areas has reached alarming proportions in recent years. We examined bark stripping by sika deer along an altitudinal gradient in the subalpine coniferous forest at three altitude ranges (1800-2000 m, 2000-2200 m, and 2200-2400 m) on the southern slope of Mt. Fuji. We tested differences in densities and diameter at breast height (DBH) of trees and those with bark-stripped stems of all tree species among the three altitude ranges. Then, we compared the relative densities of deer, based on pellet counts, to determine the impact of deer in relation to deer use and forest stand patterns across the altitudinal range studied. The results of the study show that differences in bark stripping by sika deer depended largely on the elevation and the species. Larger stems were sparsely distributed in the lowest elevation zone between 1800 and 2000 m. The relative density of deer was highest in the areas exhibiting high bark-stripping intensity on small regenerating trees of the dominant coniferous species, Abies veitchii, and on broadleaf species. In the highest elevation zone between 2200 and 2400 m, smaller stems were densely distributed, and the relative deer density was lowest where the bark-stripping intensity on small stems was lower for all three species studied. The damage to subalpine tree stems corresponded to the availability of palatable tree species with a small diameter, as reflected by the successional stage along the elevational gradient of subalpine forest on Mt. Fuji. These results suggest that the continuous impact of bark stripping on the dominant tree species might cause severe changes in forest succession. 相似文献
7.
8.
Takahashi S Hirai N Shirai M Ito K Asai F 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(7):953-956
The aim of this study was to examine the blood coagulation profiles of ferrets and compare them with those of rats. The ferret activated partial thromboplastin time (aPTT) was slightly longer than the rat aPTT. In contrast, the ferret prothrombin time and thrombin time were profoundly shorter than the corresponding rat values. The fibrinogen level in ferret plasma was 2 times higher than that in rats. Heparin prolonged all blood coagulation times in a concentration-dependent manner in both ferret and rat plasma. A significantly (P<0.01) higher concentration of heparin was required to double the aPTT in ferrets than rats. These blood coagulation data for ferrets will be useful in experimental animal studies. 相似文献
9.
This report describes the efficient plant regeneration of Chamaecyparis obtusa Sieb et Zucc. via somatic embryogenesis. Embryogenic cultures were initiated from megagametophytes containing immature zygotic embryos. Embryogenic cultures were maintained and proliferated by 2–3-week interval subcultures in medium supplemented with 2,4-dichlorophenoxyacetic acid and 6-benzylaminopurine. High maturation frequencies of cotyledonary embryos were obtained on maturation medium containing maltose, polyethylene glycol, activated charcoal, and abscisic acid. Somatic embryos germinated readily after transfer to plant growth regulator-free medium. Growth of regenerated emblings has been monitored in a greenhouse. 相似文献
10.
Micropropagation of Bolaina blanca (Guazuma crinita Mart.), a fast-growing tree in the Amazon region
Emilio Maruyama Katsuaki Ishii Isao Kinoshita Kihachiro Ohba Akira Saito 《Journal of Forest Research》1996,1(4):211-217
Rapid clonal propagation of Bolaina blanca (Guazuma crinita Mart.) was established by the subculturing of the shoot-tips from aseptically germinated seedlings on woody plant medium
(WPM) supplemented with trans-zeatin [trans-6-(4-Hydroxy-3-methylbut-2-enylamino)purine] (ZEA). After 45 days of culture,
a seven-fold multiplication rate was achieved on WPM containing 10 μM of ZEA. Obtained shoots were simultaneously elongated
and rooted on WPM containing 1 μM of kinetin [6-furfurylaminopurine] (KIN). After 60 days of culturing the growth of shoots
was evident, and high rooting percentages were obtained. The plantlets were transferred into pots with vermiculite and acclimatized
successfully in plastic boxes with transparent cover inside the growth cabinet. 相似文献