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121.
Azolla has been used as a green manure for rice in Vietnam and southern China (3). Recently it was adopted by farmers in the Koronadal area in South Cotabato Province, the Philippines (2). In that area Azolla pinnata grows reasonably well without phosphate fertilizer, which is generally used for stimulating Azolla growth (3, 5).  相似文献   
122.
Abstract

The amount and composition of phospholipid fatty acids (PLFAs) in the percolating water taken from different depths of soil (10 cm, PW10; 40 cm, PW40) and floodwater (FW) in a paddy field were compared during the period of rice cultivation. The amounts of PLFAs in PW10, PW40, and FW ranged from 22.6 to 46.2 μg L?1, from 22.3 to 54.5 μg L?1, and from 82.9 to 179.0 μg L?1, respectively. The PLFA profiles in PW10, PW40, and FW were similar to each other and 16 : 1ω7c, 18 : 1ω7, and 16 : 0 PLFAs were dominant components, irrespective of the sampling site and sampling time. High proportions of straight mono-unsaturated PLFAs ranging from 42.0 to 76.5% suggested that Gram-negative bacteria were the major members in the microbial communities of the water samples studied. A potential indicator of the environmental stresses imposed upon the microbiota that was represented by the trans vs. cis ratio of 16 : 17 PLFA was constantly low (< 0.05), indicating that the microbial communities at these sites were hardly stressed.  相似文献   
123.
To identify the microbial communities responsible for the decomposition of rice straw compost in soil during the rice cultivation period, phospholipid fatty acid (PLFA) composition of rice straw compost was determined by periodically sampling the compost from a Japanese rice field under flooded conditions. About 21% of the compost was decomposed within a period of 3 months. The total amount of PLFAs, as an indicator of microbial biomass, was significantly lower under drained conditions than under flooded conditions and was relatively constant during the flooding period. This indicates that the microbial biomass in the compost samples did not increase during the gradual decomposition of rice straw compost under flooded conditions. The proportion of branched-chain PLFAs (biomarker of Grampositive and anaerobic Gram-negative bacteria) slightly decreased during the early period after placement, and increased gradually afterwards. Among the branched-chain PLFAs, i15:0, ail5:0, i16:0 and i17:0 PLFAs predominated and their proportions increased gradually except for i16:0. The proportion of straight mono-unsaturated PLFAs (biomarker of Gramnegative bacteria) was almost constant throughout the period, and 18:1ω9 and 18:1ω7 PLFAs predominated. The proportion of straight poly-unsaturated PLFAs as a biomarker of eukaryotes including fungi was also constant throughout the period, except for a decrease under drained conditions. Straight poly-unsaturated PLFAs consisted mainly of 18:2ω6c PLFA. Therefore, these results suggest that the proportions of Gram-positive and anaerobic Gram-negative bacteria increased during the decomposition of rice straw compost in flooded paddy field. Statistical analyses enabled to divide PLFA patterns of microbiota in the rice straw compost into two groups, one group consisting of rice straw compost samples collected before mid-season drainage and the other of samples collected after mid-season drainage. Small squared distances among samples in cluster analysis indicated that the community structure of microbiota was similar to each other as a whole. These results suggest that the microbial communities changed gradually during the period of placement, and that mid-season drainage may have affected the community structure of microbiota. Principal component analysis of the PLFA composition suggested that the succession of microbiota along with the decomposition in flooded soil was similar between rice straw compost and rice straw and that the changes in the community structure during the decomposition in flooded soil were more conspicuous for rice straw than for rice straw compost.  相似文献   
124.
Vertnin (VRTN) is involved in the variation of vertebral number in pigs and it is located on Sus scrofa chromosome 7. Vertebral number is related to body size in pigs, and many reports have suggested presence of an association between body length (BL) and meat production traits. Therefore, we analyzed the relationship between the VRTN genotype and the production and body composition traits in purebred Duroc pigs. Intramuscular fat content (IMF) in the Longissimus muscle was significantly associated with the VRTN genotype. The mean IMF of individuals with the wild‐type genotype (Wt/Wt) (5.22%) was greater than that of individuals with the Wt/Q (4.99%) and Q/Q genotypes (4.79%). In addition, a best linear unbiased predictor of multiple traits animal model showed that the Wt allele had a positive effect on the IMF breeding value. No associations were observed between the VRTN genotype and other production traits. The VRTN genotype was related to BL. The Q/Q genotype individuals (100.0 cm) were longer than individuals with the Wt/Q (99.5 cm) and Wt/Wt genotypes (98.9 cm). These results suggest that in addition to the maintenance of an appropriate backfat thickness value, VRTN has the potential to act as a genetic marker of IMF.  相似文献   
125.
Not only physiological phenomena but also pathological phenomena can now be explained by the change of signal transduction in the cells of specific tissues. Commonly used cellular signal transductions are limited. They consist of the protein–tyrosine kinase dependent or independent Ras-ERK pathway, and the PI3K-Akt, JAK-STAT, SMAD, and NF-κB-activation pathways. In addition, biodegradation systems, such as the ubiquitin–proteasome pathway and autophagy, are also important for physiological and pathological conditions. If we can control signaling for each by a low-molecular-weight agent, it would be possible to treat diseases in new ways. At present, such cell signaling inhibitors are mainly looked for in plants, soil microorganisms, and the chemical library. The screening of bioactive metabolites from deep-sea organisms should be valuable because of the high incidence of finding novel compounds. Although it is still an emerging field, there are many successful examples, with new cell signaling inhibitors. In this review, we would like to explain the current view of the cell signaling systems important in diseases, and show the inhibitors found from deep-sea organisms, with their structures and biological activities. These inhibitors are possible candidates for anti-inflammatory agents, modulators of metabolic syndromes, antimicrobial agents, and anticancer agents.  相似文献   
126.
Osmerus (Spirinchus) lanceolatus egg lectin (OLL) is a member of the rhamnose-binding lectin (RBL) family which is mainly found in aqueous beings. cDNA of OLL was cloned, and its genomic architecture was revealed. The deduced amino acid (aa) sequence indicated that OLL was composed of 213 aa including 95 aa of domain N and 97 aa of domain C. N and C showed 73 % sequence identity and contained both -ANYGR- and -DPC-KYL-peptide motifs which are conserved in most of the RBL carbohydrate recognition domains. The calculated molecular mass of mature OLL was 20,852, consistent with the result, and 20,677.716, from mass spectrometry. OLL was encoded by eight exons: exons 1 and 2 for a signal peptide; exons 3–5 and 6–8 for N- and C-domains, respectively. Surface plasmon resonance spectrometric analyses revealed that OLL showed comparable affinity for Galα- and β-linkages, whereas Silurus asotus lectin (SAL), a catfish RBL, bound preferentially to α-linkages of neoglycoproteins. The Kd values of OLL and SAL against globotriaosylceramide (Gb3) were 1.69 × 10?5 M for and 2.81 × 10?6 M, respectively. Thus, the carbohydrate recognition property of OLL is slightly different from that of SAL. On the other hand, frontal affinity chromatography revealed that both OLL and SAL interacted with only glycolipid-type oligosaccharides such as Gb3 trisaccharides, not with N-linked oligosaccharides. The domain composition of these RBLs and an analytical environment such as the “cluster effect” of a ligand might influence the binding between RBL and sugar chains.  相似文献   
127.
D-Glucosamine hydrochloride (GlcN∙HCl) is an endogenous amino monosaccharide synthesized from glucose that is useful in the treatment of joint diseases in both humans and animals. The aim of this study was to examine amino acid metabolism in dogs after oral administration of GlcN∙HCl. Accelerated fumarate respiration and elevated plasma levels of lactic acid and alanine were observed after administration. These results suggest that oral administration of GlcN∙HCl induces anaerobic respiration and starvation in cells, and we hypothesize that these conditions promote cartilage regeneration. Further studies are required to evaluate the expression of transforming growth factor-beta (TGF-β).  相似文献   
128.
We evaluated the anti-tumor activities of the oral administration of fucoidan extracted from Cladosiphon okamuranus using a tumor (colon 26)-bearing mouse model. The materials used included low-molecular-weight fucoidan (LMWF: 6.5–40 kDa), intermediate-molecular-weight fucoidan (IMWF: 110–138 kDa) and high-molecular-weight fucoidan (HMWF: 300–330 kDa). The IMWF group showed significantly suppressed tumor growth. The LMWF and HMWF groups showed significantly increased survival times compared with that observed in the control group (mice fed a fucoidan-free diet). The median survival times in the control, LMWF, IMWF and HMWF groups were 23, 46, 40 and 43 days, respectively. It was also found that oral administration of fucoidan increased the population of natural killer cells in the spleen. Furthermore, from the results of the experiment using Myd-88 knockout mice, it was found that these effects are related to gut immunity. These results suggest that fucoidan is a candidate anti-tumor functional food.  相似文献   
129.
黑龙江省玉米种植效益调查   总被引:3,自引:2,他引:1  
通过调查了解黑龙江省玉米生产基本概况、生产优势、存在问题以及影响农民增收和农业可持续发展的主要因素,分析了黑龙江省玉米种植成本及价格趋势,并提出了发展玉米生产的对策,包括:提高玉米单产、推广农业机械化、改善玉米生产条件、规范整顿农资市场、调整种植模式和改进玉米品质等。  相似文献   
130.
Tropical and subtropical homegardens often show variation in floristic and structure depending on household characteristics. This research investigated how the household characteristics could influence homegarden vegetation characteristics for 50 randomly selected households in Kalaroa Upazila of Satkhira District, Bangladesh. The central analytical tool to test the relationships between household and homegarden characteristics was multiple linear regression. The results revealed that household landholdings, income, homestead size, and time spent for homegardening were strong predictors of homegarden vegetation characteristics. Economic conditions of the household, experience of the household head, and homegarden investment explained 48 % of the total plant diversity. The combined effects of all significant variables explained about 57 % of the variability in species richness. If homegarden species composition and structure receive attention by concerned authorities, the development of economically viable and ecologically sustainable homegardens can be one aim of the policy guidelines with regard to natural resource conservation and sustainable management basis in Bangladesh could act as a principal source for employment of women in rural Bangladesh.  相似文献   
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