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31.
The newly developed assay system using recombinant Leishmania amazonensis expressing enhanced green fluorescent protein (La/egfp) has been applied to the screening of Japanese marine sponges for antileishmanial activity. Bioassay-guided fractionation of an active sponge Neopetrosia sp. afforded an active compound which was identified as renieramycin A by spectroscopic analysis. It inhibited La/egfp with an IC50 value of 0.2 μg/mL.  相似文献   
32.
Summary

Based on the cDNA sequences encoding sweet cherry self-incompatibility associated ribonucleases (S-RNases), a PCR-based S-allele typing system for sweet cherry cultivars has been recently developed. Using this technique, we determined S-genotypes of the three newly released Japanese cvs Kouka-Nishiki, Beni-Sayaka and Beni-Shuho and one British cv Merton Glory that was classified as a Universal Donor, which is able to be used as a pollen donor for all cultivars in pollen incompatibility groups I to XIII. Furthermore, we also determined the partial sequences of the S-RNase genes of ‘Rainier’ (S1S4)‘ and ‘Sato-Nishiki (S3S6)’,which leads to the development of a more reliable S-allele identification method of PCR-RFLP for sweet cherry cultivars. Total DNA isolated from leaves of the four cultivars along with those from ten cultivars with known S-genotypes were PCR amplified with two sets of primers that were designed from DNA sequences encoding the signal peptide (Pru-T2) and two conserved domains (Pru-C2 and Pru-C4R) of sweet cherry S-RNases. By comparing the size of PCR products on agarose gel, the 5-genotypes of ‘Kouka-Nishiki’, ‘Beni-Sayaka’, ‘Beni-Shuho’ and ‘Merton Glory’ were suggested to be S1S3, S1S6, S4S6, and S4S6, respectively. Two of these three S-genotypes (S1S6 and S4S6) were found for the first time. DNA sequencing of PCR products from S-alleles of ‘Rainier’ and ‘Sato-Nishiki’ revealed that Ban II, Nru I, Apa LI and Ava I sites, respectively, were unique in the S1-, S3-, S4- and S6- sequences flanked by Pru-T2 and Pru-C4R primers. RFLP analysis of the PCR products using these enzymes confirmed that S1-, S3-, S4- and S6-alleles of the four cultivars contained the respective restriction enzyme recognition sites.  相似文献   
33.
The datasets of net ecosystem CO2 exchange (NEE) were acquired from 21 forests, 3 grasslands, and 3 croplands in the eastern part of Asia based on the eddy covariance measurements of the international joint program, CarboEastAsia. The program was conducted by three networks in Asia, ChinaFLUX, JapanFlux, and KoFlux, to quantify, synthesize, and understand the carbon budget of the eastern part of Asia. An intercomparison was conducted for NEE estimated by three gap-filling procedures adopted by ChinaFLUX, JapanFlux, and KoFlux to test the range of uncertainty in the estimation of NEE. The overall comparison indicated good agreement among the procedures in the seasonal patterns of NEE, although a bias was observed in dormant seasons depending on the different criteria of data screening. Based on the gap-filled datasets, the magnitude and seasonality of the carbon budget were compared among various biome types, phenology, and stress conditions throughout Asia. The annual values of gross primary production and ecosystem respiration were almost proportional to the annual air temperature. Forest management, including clear-cutting, plantation, and artificial drainage, was significant and obviously affected the annual carbon uptake within the forests. Agricultural management resulted in notable seasonal patterns in the crop sites. The dataset obtained from a variety of biome types would be an essential source of knowledge for ecosystem science as well as a valuable validation dataset for modeling and remote sensing to upscale the carbon budget estimations in Asia.  相似文献   
34.
The D4 dopamine receptor (D4DR) polymorphic region, which is possibly related to the personality trait known as novelty seeking in humans, was examined in 34 dogs from two breeds (Golden retriever and the Japanese indigenous breed, Shiba) by the polymerase chain reaction (PCR), and the DNA sequences of each allele were determined. The polymorphic region of the dog D4DR gene was composed of 39- and 12- base pair (bp) units, and four alleles (A-D) were identified based on the number and/or order of these units. Intra- and inter-breed allele variations were observed. The frequency of the short A allele was dominant (78.9%) in the Golden retriever, while the long D allele was most common (46.7%) in the Shiba. These findings suggested that the allele frequency varied significantly between different breeds, and that analysis of the polymorphism in D4DR might be of use for understanding the behavioral traits of dogs.  相似文献   
35.
Various canine breeds are remarkably different from each other not only in their sizes and shapes but also in behavioral traits, suggesting that some of them are under genetic control. Although dopaminergic neurotransmission system is considered to affect animal behavior, little is known about related genes in canine. Relations between specific alleles in polymorphic regions of the dopamine receptor D4 gene (DRD4) and personality or psychiatric disorders have been reported in humans, and we first found polymorphism in exon III region of the gene in 4 canine breeds. In this study we surveyed allele frequency distribution in 23 breeds including a total of 1,535 unrelated individuals. In exon III, 8 alleles including a novel allele were identified. A group of breeds in which the alleles 447b, 498 and 549 were frequent tended toward high scores in aggression-related behavioral traits than that with frequent alleles 435 and 447a. Moreover, a polymorphism based on 24 bp insertion/deletion was found in exon I region for the first time in dogs. This information may be of use for candidate gene studies of behavioral variation in dogs.  相似文献   
36.
A bottom sediment collected in a marina was analyzed for organotin species, and >20 organotin compounds including biodegraded ones were confirmed by comparison with the synthesized standards using gas chromatography (GC)/mass spectrometry and a GC/atomic emission detection system. Their structures were also determined in comparison with those in a technical grade of tri-n-butyltin chloride (TBTC). Eleven organotin compounds were found in the technical TBTC. Among them, unexpected organotin compounds, such as di-n-butyl(2-ethylhexyl)tin chloride and di-n-butyloctyltin chloride, were identified, although the levels were low. These compounds were also found in the sediment sample. The relationship between organotin compounds in the technical TBTC and those in marine products was also discussed.  相似文献   
37.
The concept of productive efficiency of nutrients has been discussed at length by Kimura and Chiba (1943)1). Considering that the effect of a nutrient for the production of grain and straw may be divided into several growing periods of plant.life, Kimura and Chiba (1943) conducted water culture experiments to study the effect of nitrogen absorbed at a definite period on the production of grain and straw. The total productive efficiency was divided into several partial efficiencies based upon the growing period of the rice plant. The following is a summary of their findings.  相似文献   
38.
Abstract

The monosaccharides in acid hydrolysates were monitored in soil which was packed in a bag made of glass microfiber paper and buried in upland and paddy fields for up to 36 months. During the initial flush of decomposition, all constituent monosaccharides except for non cellulosic glucose were found to decrease. The amounts which disappeared were greater than the water extractable saccharides of the air dried soil or ground sample of the air dried soil. After the flush of decomposition, the changes in mannose, galactose, fucose and rhamnose were small, whereas cellulosic glucose, arabinose and xylose continued to decline in the upland field soil. The soil saccharides are classified into six groups and their relative persistency is discussed.

The monosaccharide composition did not change markedly, but the proportion of monosaccharides relating to plant materials declined with time after incubation. The molar ratios of hexoses to pentoses, deoxyhexoses to pentoses, and non-cellulosic glucose to cellulosic glucose increased gradually, whereas a gradual decline in the ratio of xylose to mannose was observed when the soil received no plant materials under field conditions.  相似文献   
39.
To identify DNA markers linked to a fertility restorer (Rf) genefor Ogura cytoplasmic male sterility in radish (Raphanus sativus L.),a non-radioactive, amplified fragment length polymorphism (AFLP) analysiswas performed on bulked DNA samples from male-sterile and male-fertileradishes. Ten male-fertile and 10 male-sterile plants selected arbitrarilyfrom an F2 population made by selfing of F1 plant from a crossbetween a male-sterile (`MS-Gensuke') plant and a restorer (`Comet') plantwere used as material. Using 32 AFLP primer pairs, one AFLP fragment(AFLP190) which is specific to the bulked DNA samples from male-fertileF2 plants was identified. AFLP190 was characterized by molecularcloning and nucleotide sequencing, and was converted to a sequence-taggedsite (STS) marker, STS190. A linkage analysis performed in 126individuals of two independent F2 populations showed tight linkageof STS190 to the Rf gene. The rate of recombination between themarker and Rf was estimated to be less than 1%, making STS1901.2 cM from the gene.  相似文献   
40.
Wheat grains were germinated in the dark at room temperature (24°C) for 1, 2, 3, 5, and 8 days. Germinated wheat grains were pearled in a Waring blender, and the outer bran layers were separated from the pearled grains. Breadmaking was performed with wheat flour and 10% of the outer bran layer. Breadmaking properties (bread height [mm] and specific volume [cm3/g]) were gradually enhanced by blending the germinated outer bran layers, and maximum specific volume was obtained after 5 days of germination. However, the improvement was lost after 8 days of germination. Rapid ViscoAnalyser (RVA) and Brabender Farinograph profiles of wheat flour and outer bran layers (10%) indicated that the maximum decrease of peak viscosity and increase of angle of tail were obtained after 3 and 5 days of germination, respectively. Those changes are presumed to be due to the action of enzymes found in the outer bran layers. Activities of α‐ and β‐amylase, lipase, protease, and xylanase in the outer bran layers were measured, and correlation coefficients (r) between breadmaking properties and peak viscosity (RVA), angle of tail (farinograph), and enzyme activities were calculated. These data suggest that xylanase and α‐amylase activities in the outer bran layers were highly related to the enhancement of the breadmaking properties.  相似文献   
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