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91.
Taira O Watanugi I Hagiwara Y Takahashi M Arai S Sato H Maehara N 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(10):1059-1062
We cloned five new subtypes of cDNA encoding canine interferon-alpha (CaIFN-alpha) from a canine epithelial cell line. CaIFN-alphas were divided into two groups by amino acid sequences and a molecular phylogenic tree. Two subtypes of them were expressed in Escherichia coli, and IFN proteins were purified. Recombinant CaIFN-alphas were highly species-specific and showed antiviral activity against Vesicular stomatitis New Jersey virus and canine adenovirus-1 , but not against canine herpesvirus-1. 相似文献
92.
1994至1997年研究了粳稻短根基因srt1导入3个籼稻保持系和3个粳稻保持系的F1、苗期短根的F2和F3的农艺性状及根长表现。结果表明:1) RM1与3个籼稻保持系杂交,F1植株高达150 cm , 抽穗迟,穗型大,结实率只有43%~47%;而与粳稻保持系杂交,F1株高125 cm以下,结实率82%~91%。2) F2短根秧苗移栽大田后,一部分植株逐渐死亡,一部分抽穗成熟,而少部分株型类似保持系的植株株高、结实都正常。3) 六千辛B/RM1组合中苗期短根、成熟期株高结实都正常的F2植株所衍生的F3株系,种子发芽后11 d以内冠根长度短于六千辛B、Ohchikara、六优1号。 相似文献
93.
We compared the diet of Ommastrephes bartramii paralarvae with morphological changes in their beaks and proboscis (fused tentacles). The paralarvae were collected north
of the Hawaiian Islands during 2001 and 2002 and ranged in mantle length (ML) from 1.1 to 13.2 mm. They fed on crustaceans,
including copepods (copepodite stage) and amphipods. The rostral tips of upper and lower beaks began to protrude anteriorly
at around 3–4 mm ML, and the smallest paralarva with identifiable prey in its digestive tract was 4.2 mm ML, which suggests
that the paralarvae can masticate prey soon after the beaks protrude. The proboscis separated into two tentacles at 9.3–13.2 mm
ML, but the newly formed tentacles were weakly developed even in the largest specimen, suggesting that tentacles do not operate
functionally and that the arms are used to capture prey. 相似文献
94.
Nopporn Manajit Takafumi Arimoto Osamu Baba Seiichi Takeda Aussanee Munprasit Kamolrat Phuttharaksa 《Fisheries Science》2011,77(4):447-454
The Japanese type of set-net, Otoshi-ami, was introduced to Thailand in 2003 with the aim of assessing its feasibility as
a sustainable coastal fisheries management tool for the empowerment of coastal fishers’ communities. All preparations for
constructing and installing the set-net in the coastal waters off Mae Rumpheung beach, Rayong Province, Thailand, were carried
out by local fishers, with technical advice and support from national and international institutions. The gear was modified
and developed to suit the conditions of the fishing ground and target species. Data on the catch and sales trends in Rayong
using the set-net were collected for 7 years for statistical analysis; during this period, the gear design and marketing strategies
were improved. Simulation analysis for evaluating the cost–profit bases was conducted to establish a model for set-net technology
transfer in Southeast Asia, based on differing numbers of fishers and operation days. The simulation results show the required
size of the average daily catch to cover the total cost according to the average unit price, where the economic return point
is an average catch of 128 kg, based on a unit price of 25 Baht/kg (0.83 USD/kg), with ten fishermen and a daily operation
cost of 3,200 Baht (USD 106.17). 相似文献
95.
96.
In order to improve the efficiency of stock enhancement programs for the sea urchin Hemicentrotus pulcherrimus, information on food algal species, which affect growth and gonad production greatly, is necessary. Since it is difficult to identify species from the macroalgal fragments within the gut contents of the sea urchin by microscopic observation, we tried to apply a DNA barcoding method for gut contents analysis. We used a partial rbcL gene sequence for taxonomic section and newly designed primer sets, respectively, for brown algae and for red algae. Direct sequencing of the PCR products was carried out. Species identification was based on the phylogenetic relationship. We could objectively identify four species and two taxonomic groups (genus or family) in brown algae, and two species and four taxonomic groups in red algae from the gut contents. Sargassum hemiphyllum was the most abundant brown alga in the gut contents but was not dominant in the study site. The result showed the importance of identification to the species level. In addition, red algal epiphytes were detected with brown algal fragments. The DNA barcoding method will enable the researchers to verify the important role of epiphytes as a potential food source. 相似文献
97.
Ko Fujioka Ryo Kawabe Alistair J. Hobday Yoshimi Takao Kazushi Miyashita Osamu Sakai Tomoyuki Itoh 《Fisheries Science》2010,76(3):403-410
Acoustic tags were used to examine the spatial and temporal distribution of southern bluefin tuna (SBT) in southern Western Australia, which is in a region where fishery-independent acoustic surveys of the recruitment abundance index of SBT have been historically undertaken. We investigated patterns of SBT distribution within and inshore of the acoustic survey area during three summer seasons. Annual differences in distribution patterns were characterized by two distinctive migration pathways. An inshore-migrating pathway was observed in two seasons (2004/2005 and 2006/2007), with a relatively high proportion of tagged SBT (84.5, 65.0%) migrating inshore of the acoustic survey area. The other pathway was concentrated along the shelf (2005/2006 season), with an estimated 63.3% of tagged SBT moving within the survey area. These variable migration patterns may bias the interannual fluctuations in abundance indices. Current survey methods can be modified to include both inshore and continental shelf areas. This contribution shows that the accuracy of acoustic surveys can be improved by including ecological patterns. 相似文献
98.
99.
Masaharu Kubota Osamu Tamura Yasuhiro Nomura Noriko Orihara Norihito Yamauchi Kengo Yonemoto Kenichiro Chiba Nobutaka Someya 《Journal of General Plant Pathology》2017,83(2):117-120
Isolates of spinach downy mildew fungus, Peronospora farinosa f. sp. spinaciae, collected at seven sites in Japan from December 2013 to March 2016, were identified as belonging to races 8, 10, 12 and 13, and one was unauthorized. Races 10, 12, 13 and the unauthorized were first found in Japan. 相似文献
100.
Tomoaki Morishita Ryusuke Hatano Osamu Nagata Kohei Sakai Takahiro Koide Osamu Nakahara 《Soil Science and Plant Nutrition》2013,59(8):1187-1194
Abstract It has been well documented by short-term artificial experiments that the CH4 uptake is inhibited by N input, especially NH4 p+-N input. To investigate the effect of the natural N input by throughfall and other factors on the CH4 uptake in forest soils, we measured the CH4 uptake rates for 6 months during the snow-free period of the year and N input by throughfall throughout the year at 10 sites in Hokkaido, Japan, from 1997 to 2002. Water filled pore space (WFPS) and pH values in the soils varied widely among the sites (38-93% and 3.9-6.2, respectively). The rates of NH4 p+-N and NH3 p--N inputs ranged from 1.3 to 6.9 kg N hap-1 yearp-1 and from 0.8 to 2.9 kg N hap-1 yearp-1, respectively. The NH4 p+-N input was generally higher than the NH3 p--N input. Total N input by throughfall amounted to 2.3-9.4 kg N hap-1 yearp-1. The highest CH4 uptake rate occurred within the period from July to September (41-215 μg CH4 mp-2 hp-1) each year at most sites. CH4 uptake rate was relatively low (~50 μg CH4 M-2 hp-1) at northern sites, while a high CH4 uptake rate was observed throughout the year 100 (? CH4 mp-2 hp-1) at southern sites. The mean CH4 uptake rates were significantly different among the sites. Cumulative CH4 uptake ranged from 1.4 to 6.6 kg CH4 hap-1 [184 d]p-1 with a mean values of 3.22 ± 1.36 kg CH4 hap-1 [184 d]p-1. Cumulative CH4 uptake increased with increasing temperature and decreased with an increase in precipitation (Rain), NH4 p+-N input (TFNH4) WFPS, soil total C (TC), and total N (TN). There was a quadratic relationship between the CH4 uptake and NH3 p--N input (TFNO3), soil pH, and C / N ratio in soil. A regression equation was obtained as follows to predict the CH4 uptake in forest soils: Cumulative CH4 uptake = 0.47 / Rain + 0.38 / TFNH4 + 0.34 / TC - 0.30 / TFN03 (R p2 = 0.74, p = 0.0001). This equation indicates that atmospheric N input into forest soils is one of the main factors that control cumulative CH4 uptake with precipitation, total carbon content in soil in Hokkaido, Japan. 相似文献