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81.
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83.
稻瘟病菌致病性遗传研究初报——云南省稻瘟病菌有性世代研究之五 总被引:1,自引:0,他引:1
本文报道龙爪稷分离菌G10-1马水稻分离菌后代菌性2145-R-57-1交配产生的同一子囊中分离出的子囊孢子致病性及交配型分离情况.交配型分离比1:1;但致病性分离情况比较复杂.很多子囊孢子菌株失去亲本菌株对供试水稻和龙爪稷的致病性,少数菌株获得亲本菌株所没有的致病性.对稻瘟病菌致病性的遗传尚需作大量分析工作. 相似文献
84.
Yamaguchi A Clayton RN Mayeda TK Ebihara M Oura Y Miura YN Haramura H Misawa K Kojima H Nagao K 《Science (New York, N.Y.)》2002,296(5566):334-336
Eucrites are a class of basaltic meteorites that share common mineralogical, isotopic, and chemical properties and are thought to have been derived from the same parent body, possibly asteroid 4 Vesta. The texture, mineralogy, and noble gas data of the recently recovered meteorite, Northwest Africa (NWA) 011, are similar to those of basaltic eucrites. However, the oxygen isotopic composition of NWA011 is different from that of other eucrites, indicating that NWA011 may be derived from a different parent body. The presence of basaltic meteorites with variable oxygen isotopic composition suggests the occurrence of multiple basaltic meteorite parent bodies, perhaps similar to 4 Vesta, in the early solar system. 相似文献
85.
Yi Zhang Kounosuke Otomaru Kazunaga Oshima Yuji Goto Ichiro Oshima Susumu Muroya Mitsue Sano Rena Saneshima Yukiko Nagao Aoi Kinoshita Yasuko Okamura Sanggun Roh Akira Ohtsuka Takafumi Gotoh 《Animal Science Journal》2021,92(1):e13600
This study aimed to investigate the effects of high and low levels of energy intake during the entire gestation period on the skeletal muscle development, organ development, and adipose tissue accumulation in fetuses of Wagyu (Japanese Black) cows, a breed with highly marbled beef. Cows were allocated to a high-nutrition (n = 6) group (fed 120% of the nutritional requirement) or low-nutrition (n = 6) group (fed 60% of the nutritional requirement). The cows were artificially inseminated with semen from the same sire, and the fetuses were removed by cesarean section at 260 ± 8.3 days of fetal age and slaughtered. The whole-body, total muscle, adipose, and bone masses of the fetal half-carcasses were significantly higher in the high-nutrition group than the low-nutrition group (p = 0.0018, 0.009, 0.0004, and 0.0362, respectively). Fifteen of 20 individual muscles, five of six fat depots, nine of 17 organs, and seven of 12 bones that were investigated had significantly higher masses in the high-nutrition group than the low-nutrition group. The crude components and amino acid composition of the longissimus muscle significantly differed between the low- and high-nutrition groups. These data indicate that maternal nutrition during gestation has a marked effect on the muscle, bone, and adipose tissue development of Wagyu cattle fetuses. 相似文献
86.
Akihiro Imaya Seiichi Ohta Nagaharu Tanaka Yoshiyuki Inagaki 《Soil Science and Plant Nutrition》2005,51(6):873-884
It is essential to analyze chemical properties including the amount of various materials and the soil colloid characteristics in forest soils to forecast wood production and the distribution of and variations in the environmental functions of forest soils, such as conservation of stream water and carbon sequestration. Approximately 70% of the forest soils in Japan consists of Brown Forest Soils (BFS), which are considered to be typical zonal soils under the humid-temperate and warm-temperate regime of Japan. BFS were subclassifled into several groups according to the soil moisture environment along the slope and morphological properties. However, even the same type of soil may display different properties depending on the climatic conditions, parent materials and vegetation types. In the present study, the variations in the carbon content, nitrogen content, cation exchange capacity and some properties depending on the parent materials, were clarified by using 34 sola of BFS, and 3 sola of black soils (BLS) for comparison, which were distributed in the submontane zone of the Kanto and Chubu districts in central Japan under the same climatic conditions. We observed differences in the pH, cation exchange capacity, base saturation and clay content among BFS samples derived from various parent materials. The BFS derived from volcanic ash contained obviously larger amounts of carbon and nitrogen than the BFS derived from other parent materials. However, the BFS derived from volcanic ash differed from the BLS derived from volcanic ash in the vertical distribution pattern of carbon and nitrogen. Thus, even in the submontane zone of the Kanto and Chubu districts, the chemical properties of BFS varied considerably with the parent materials. It was concluded that the classification of BFS by the parent materials was useful for evaluating the ability of the BFS, that cover 70% of the forests in Japan, to store various materials. 相似文献
87.
A unique lipoprotein profile was found in the plasma of cultured Japanese eel,Anguilla japonica which accumulated more lipid in its muscle than in its liver. The plasma lipoprotein level of Japanese eels was in excess of 54 mg ml1, a concentration considered to be hyperlipoproteinemic in relation to other teleosts. The plasma lipoproteins consisted of very low density lipoprotein (VLDL, density (d)<1.006 g ml1) low density lipoprotein (LDL, 1.0061), high density lipoprotein 2 (HDL2, 1.0851), and HDL3 (1.1001). VLDL, but not HDL, was the main component in the plasma of Japanese eels, unlike most teleosts where HDL is the main component. An additional lipoprotein, vitellogenin (1.2101), was induced by the injection of estradiol-17ß (E2), but VLDL was the main plasma component even in the E2-treated eels. VLDL was a triacylglycerol (TG)-rich lipoprotein and possessed two apolipoprotein (apo) B-like proteins of molecular weights (Mr) 260K and 230K as main components.LDL, HDL2, and HDL3 were revealed to consist of heterogeneous components by a density gradient ultracentrifugation. LDL was separated into three subclasses of LDL1 (1.0301), LDL2 (1.0431), and LDL3 (1.0671). LDL1 with apo B-like protein of Mr 230K was a TG-rich lipoprotein, while both LDL2 and LDL3 were cholesterol ester-rich lipoproteins with apo A-I-and A-II-like proteins of Mr 25K and 14K. The particle sizes of HDL2 and HDL3 subclasses differed, although all of HDL2 and HDL3 subclasses possessed apo A-I-and A-II-like proteins of Mr 25K and 14K as main components. To our knowledge, this is the first report of detailed plasma lipoprotein profile in Japanese eels.Corresponding author: till August 18, 1996 and after April 19, 1997: at the above address. From August 19, 1996 till April 18. 1997: c/o Dr. N.H. Haunerland, Department of Biological Sciences. Simon Fraser University, Burnaby, British Columbia, Canada V5A 1S6. 相似文献
88.
Horii T Suetake I Yanagisawa E Morita S Kimura M Nagao Y Imai H Tajima S Hatada I 《The Journal of reproduction and development》2011,57(5):579-585
Manipulation of preimplantation embryos in vitro, such as in vitro fertilization (IVF), in vitro culture (IVC), intracytoplasmic sperm injection (ICSI), somatic cell nuclear transfer (SCNT) and other assisted reproduction technologies (ART), has contributed to the development of infertility treatment and new animal reproduction methods. However, such embryos often exhibit abnormal DNA methylation patterns in imprinted genes and centromeric satellite repeats. These DNA methylation patterns are established and maintained by three DNA methyltransferases: Dnmt1, Dnmt3a and Dnmt3b. Dnmt3b is responsible for the creation of methylation patterns during the early stage of embryogenesis and consists of many alternative splice variants that affect methylation activity; nevertheless, the roles of these variants have not yet been identified. In this study, we found an alternatively spliced variant of Dnmt3b lacking exon 6 (Dnmt3bΔ6) that is specific to mouse IVC embryos. Dnmt3bΔ6 also showed prominent expression in embryonic stem (ES) cells derived from in vitro manipulated embryos. Interestingly, IVC blastocysts were hypomethylated in centromeric satellite repeat regions that could be susceptible to methylation by Dnmt3b. In vitro methylation activity assays showed that Dnmt3bΔ6 had lower activity than normal Dnmt3b. Our findings suggest that Dnmt3bΔ6 could induce a hypomethylation status especially in in vitro manipulated embryos. 相似文献
89.
Seiichi Oyamada Yasuhiro Ueno Mitsutaku Makino Koji Kotani Hiroyuki Matsuda 《Fisheries Science》2009,75(2):273-283
In the middle of the 1990s, Pacific saury fishery vessels began to install “size separators” to selectively land large-size
class fish with a higher price. Contrary to expectations, this resulted in removal of the separators in 2006 because fishers
believed the separators had contributed to price collapses in the 2000s. The intent of this paper is to investigate the effects
of separators on both the fishery economy and stock of Pacific saury by simulating population and economic models under a
single framework. For this purpose, we developed (1) an age-structured population dynamics model with stochasticity, and (2)
an economic model spanning both price and inventory dynamics with stochasticity, in which each set of model parameters were
estimated on the basis of time series data. In a 10-year simulation, the harvest quota was set constant from 20,000 to 400,000 t
at intervals of 20,000 t, and the effects of separators were incorporated by controlling the catchability of 0-year-old fish.
We found that separators increase the expected yield and reduce the deficit risk for harvests of 140,000 t and smaller. However,
separators have the opposite effects for harvests of 160,000 t and larger. 相似文献
90.
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