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排序方式: 共有847条查询结果,搜索用时 15 毫秒
81.
Rabies is an enzootic viral disease widespread throughout the world. Although it is a vaccine-preventable disease, the annual number of human deaths caused by rabies is estimated to be 32,000 in Asia. Phylogenetic analysis based on sequence data of the partial N gene of rabies viruses in Asia has shown that the viruses are divided into five genogroups, distributed in Middle East, South Asia, South East Asia, Malay, and Arctic regions. The genetic relationships among these rabies viruses agree basically with the results of previous studies. Meanwhile, new types of vaccines are being developed by applying gene manipulation techniques to rabies virus in order to overcome the disadvantages of current vaccines. This article reviews the molecular epidemiology of rabies in Asia and progress made in the development of new-generation rabies vaccines with the goal of elimination or control of rabies in Asia. 相似文献
82.
Yasushi Mizoguchi Makoto Moriya Daiki Taniguchi Akira Hasegawa 《Animal Science Journal》2014,85(2):101-111
To investigate genes involved in intramuscular adipogenesis in ruminants, 16 genes with dramatic variable expression were selected. These were selected from the differentiation‐ and proliferation‐phase libraries of our previous serial analysis of gene expression (SAGE) studies of a clonal bovine intramuscular preadipocyte (BIP) cell line. We harvested the BIP cells over 12 days after adipogenic stimulation with all‐trans retinoic acid (ATRA). Quantitative real‐time PCR confirmed the earlier SAGE study results of the expression patterns of 15 of the genes. On day 6, TG accumulation increased significantly in the BIP cells but was completely inhibited in the 3T3‐L1 cells (the monogastric reference). ATRA enhanced expression levels of six genes whereas it suppressed expression of eight genes on day 3 of adipogenesis in the BIP cells. Forty‐eight hours after transfection, the messenger RNA expression level of the adipose differentiation‐related protein (ADFP), encoded by one of the upregulated genes, in the ADFP small interference RNA (siRNA)‐transfected cells was 3.5% of that in negative control‐transfected cells. Also, 6 days after induction the TG level in the ADFP siRNA‐transfected cells was 21.8% lower than that in negative control‐transfected cells. This analysis of gene expression profiles after ATRA treatment will contribute to our understanding of the molecular mechanisms involved in bovine intramuscular adipogenesis. 相似文献
83.
84.
In several areas of Japan, rape plants (Brassica napus) show a boron deficient smyptom, resulting in a seed-maturation obstacle. And in these areas, early supply of boron before transplanting were required5,6. 相似文献
85.
Sustainability of agriculture became a major issue of global concern during this decade. Agronomic practices aimed at reducing the dependence on inputs such as chemical fertilizers can contribute to sustainability. Nitrogen (N) is the most limiting and commonly applied nutrient for crop production. The development of nutrient-responsive cultivars especially during the past three decades led to an intensive use of N fertilizers in many agricultural systems. Environmental and economic issues associated with such practices have, however, generated an interest in alternative management systems. These include practices such as exploitation of beneficial biological functions (symbiotic nitrogen fixation, etc.) and substitution of chemical fertilizers with farm-generated products. 相似文献
86.
Sutopo Ghani Nugroho Sunyoto Jamalam Lumbanraja Hermanus Suprapto Wayan Sabe Ardjasa Makoto Kimura 《Soil Science and Plant Nutrition》2013,59(4):799-809
Variations in CH4 emission from a Sumatra paddy field in which 8 popular modern varieties in Indonesia were grown were compared in the 1994/1995 rainy season. Total amounts of CH4 emitted during the period of rice growth were in the ranges of 32.6-41.7 and 51.3–64.6 g CH4 m-2 for the plots amended with chemical fertilizer only and those amended with both rice straw and chemical fertilizer, respectively. The mean CH4 emission rate was highest in the plot with the variety Bengawan solo and lowest in the plots with the varieties Atomita-4 and Way seputih among the plots which received chemical fertilizer, while highest in the plot with Way seputih and lowest in the plot with Bengawan solo among the plots amended with both rice straw and chemical fertilizer. The increase in the mean CH4 emission rates by rice straw application was higher for the plots planted with Way seputih (1.98 times) and Atomita-4 (1.77 times) than for the plots with Bengawan solo (1.23 times) and IR-64 (1.35 times). The plots with Walanai and Cisanggarung recorded intermediate mean emission rates and the increase in CH4 emission by rice straw application was also intermediate (1.57–1.64 times). It was noteworthy that Way seputih and Atomita-4 were derived from the variety Cisadane, Bengawan solo and IR-64 from the variety IR-54, and Walanai and Cisanggarung from the varieties IR-36 and Pelita 1-1, respectively. The amounts of CH. emitted for 1 kg grain production ranged from 53 (Atomita-4) to 74 (Kapuas and Walanai) and from 89-93 (IR-64, Bengawan solo, and Atomita-4) to 121 (Kapuas) g CH4 kg-1 of grain for the plots amended with chemical fertilizer and those amended with rice straw and chemical fertilizer, respectively. 相似文献
87.
Impact of fumigation with metam sodium upon soil microbial community structure in two Japanese soils
Koki Toyota Karl Ritz Shiro Kuninaga Makoto Kimura 《Soil Science and Plant Nutrition》2013,59(1):207-223
The effects of fumigation with sodium methyl dithiocarbamate (metam sodium) on the microbial community structure and function in 2 soils were investigated using a variety of techniques. In both soils ca. 50% and 90% of the populations of total and culturable bacteria, respectively, were killed by fumigation, with recovery to levels prevailing in control soils 26 d after cessation of fumigation. The size of the ammonium and nitrite oxidiser populations was reduced by up to 4 orders of magnitude by fumigation, with the latter showing a slight recovery 105 d later. There were substantial changes in the C-utilisation (Biolog GN) profiles in the fumigated soils even 105 d later. The number and pattern of amplified 16S ribosomal DNA restriction analysis (ARDRA) fragments was changed by fumigation, and there was a shift in the %G+C profile toward a greater proportion of lower %G+C classes in treated soils. It appeared that DNA released from killed cells remained for some time after fumigation, and masked the apparent community DNA profiles. This study demonstrates that the effects of fumigation on the soil microbial community structure and function were pronounced and for some parameters very persistent. However, the effects on broad-scale properties such as total or culturable bacterial numbers were less enduring. 相似文献
88.
Stability of humus in the plow layer soil is considered to affect the quantity and quality of dissolved organic matter leached from the plow layer soil. Therefore, a model experiment was conducted to analyze the effect of soil reduction under submerged conditions on the stability of humus in the plow layer soil. The changes in the stability of humus in the plow layer soil during submerged incubations with and without rice straw application were evaluated based on the changes in the binding type of humus. Binding type of humus in the plow layer soil was analyzed by successive extractions of organic matter with water, 0.25 M Na2SO4, 0.1 M Na4P2O7 (pH 7.0), 0.1 M Na4P2O7 (pH 10.5), and 0.1 M Na4P2O7 (pH 10.5) with NaBH4. Amounts of Fe, Mn, and Mg in each fraction were also determined to estimate the relationships between humus and metals. The successive extraction of humus indicated that the amount of organic carbon which was extractable with the (NaBH4 +0.1 M Na4P2O7) solution decreased while that of the 0.1 M Na4P2O7 (pH 7.0}-extractable organic carbon increased during submerged incubation with rice straw application. The origin of the increase in the amount of organic carbon in the Na4P2O7 (pH 7.0)-extractable fraction during submerged incubation was investigated further by another incubation experiment using 13C-glucose as a reducing agent. Atom- 13C% analysis showed that the contribution of organic carbon derived from compounds other than glucose to the increase in the contents of humic acids and fulvic acids in the Na4P2O7 (pH 7.0)-extractable fractions was ca. 80%. Therefore, it was concluded that the binding type of humus changed from (NaBH4 + Na4P2O7)-extractable to Na4P2O7 (pH 7.0)-extractable humus under reducing conditions. Since the amounts of organic carbon and Fe increased in the Na4P2O7 (pH 7.0)-extractable fraction and decreased in the (NaBH4 +0.1 M Na4P2O7)-extractable fraction simultaneously, iron reduction was presumably associated with the change in the binding type of humus in submerged paddy soil. 相似文献
89.
Global warming is now attracting the world attention. Methane is an important greenhouse gas next to CO2. Prather et al. (1995) estimated that rice paddy fields account for 14% of all biogenic atmospheric methane. It is considered that methane production from rice paddy fields is increasing along with the increase of the population. Therefore, the development of rice cultivation techniques for reducing methane production is essential, in order to preserve the global environment. 相似文献
90.
The effect of rice straw (RS) incorporated at the time of plowing in the previous cr–p season on CH4 emission from rice paddies was investigated in a pot experiment. Rice straw that incorporated just before transplanting of rice seedlings (June) into a paddy field was collected after the harvest (October) and at the beginning of the next cropping period (May). Methane emission rates from the rice-planted pots with the application of fresh RS, RS collected in October. and RS collected in Mayas well as the pots without RS application were measured using the chamber method. The composition of organic constituents in the three kinds of RS was estimated by the proximate analysis. The cumulative amount of CH4 emitted during the first 50–d period was lower in the order of the pots with RS collected in May, pots with RS collected in October, and pots with fresh RS. The cumulative amount of CH4 emitted throughout the rice growth period from the pots with fresh RS and with RS collected in October was significantly larger while that from the pots with RS collected in May did not differ statistically compared with the total CH4 emission from the pots without RS. These results suggested that there was an overall decrease in the amount of organic constituents in RS based on the large differences in T-C content and similar composition of organic constituents between the fresh RS and RS collected in May. Significant effect of RS continuously applied during the previous cropping period on the increase in CH4 emission was discussed. 相似文献