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81.
坡面治理工程对土壤硬度和土壤厚度影响的研究   总被引:1,自引:0,他引:1  
该文以日本长野县野底川流域的割泽支流域为对象 ,用土壤剖面法和简易打击试验法对坡面治理工程施工地的土壤硬度及厚度变化进行了调查 .用长谷川式简易打击机所得到的调查结果表明 ,坡面治理工程施工后的斜坡土壤硬度的变化是很复杂的 ,与土壤深度没有明显的关系 .土壤A层厚度随着坡面治理工程经过年数的增多而有增大的趋势 ,而简易打击试验所得到的打击值在 1 5cm/次以上的表层土壤厚度的变化却与坡面治理工程经过年数没有关系 ,而可能受施工时挖、填土状况的影响 .本次调查结果进一步证实为了改善植物根系的生育环境 ,必须增大表层土壤的厚度  相似文献   
82.
Inhibitory effects of apple polyphenol extract (AP) and procyanidin contained in AP on in vitro pancreatic lipase activity and in vivo triglyceride absorption in mice and humans were examined. AP and procyanidin considerably inhibited in vitro pancreatic lipase activity. However, polyphenols, except for procyanidin, in AP (i.e., catechins, chalcones, and phenol carboxylic acids) showed weak inhibitory activities on pancreatic lipase. Procyanidins separated by normal-phase chromatography according to the degree of polymerization were also examined. Inhibitory effects of procyanidins increased according to the degree of polymerization from dimer to pentamer. On the other hand, pentamer or greater procyanidins showed maximal inhibitory effects on pancreatic lipase. These results suggested that with respect to in vitro pancreatic lipase inhibition, the degree of polymerization was an important factor and oligomeric procyanidin mainly contributed. Next, we performed a triglyceride tolerance test in mice and humans. Simultaneous ingestion of AP and triglyceride significantly inhibited an increase of plasma triglyceride levels in both models. These results suggested that the oligomeric procyanidins contained in AP inhibited triglyceride absorption by inhibiting pancreatic lipase activity in mice and humans.  相似文献   
83.
Metabolic syndrome is a risk factor for cardiovascular diseases and has become increasingly common in Japan. Epidemiological studies show inverse associations between intake of whole wheat grains and metabolic syndrome, but few dietary intervention trials have investigated the effect of whole wheat grain consumption. It was investigated whether a diet in which refined wheat bread (RW diet) was substituted by whole grain wheat bread (WW diet) would reduce visceral fat obesity in Japanese subjects. A randomized double-blind placebo-controlled intervention study was conducted in 50 Japanese subjects with body mass index (BMI)?≥?23 kg/m2. Subjects were randomly assigned WW (WW group) or RW diets (RW group) for 12 weeks. Blood samples and computed tomography scans were obtained every 6th week. The WW group showed decrease (?4 cm2) in visceral fat area (VFA) (p <?0.05), whereas the RW group showed no significant changes. These time-dependent changes were significantly different between the groups. WW diet led to significant and safe reductions in VFA in subjects with BMI?≥?23 kg/m2. WW diet may contribute to preventing visceral fat obesity.  相似文献   
84.

Background

Rice blast is the most serious disease afflicting rice and there is an urgent need for the use of disease resistance (R) genes in blast tolerance breeding programs. Pb1 is classified as a quantitative resistance gene and it does not have fungal specificity. Pb1-mediated resistance develops in the latter stages of growth. However, some cultivars, such as Kanto209 (K209), cultivar name Satojiman, despite possessing Pb1, do not exert resistance to rice blast during the reproductive stage.

Results

We found that the expression of WRKY45 gene downstream of Pb1 was weakly induced by rice blast inoculation at the full heading stage in K209. Genetic analysis using the SNP-based Golden Gate assay of K209 crossing with Koshihikari Aichi SBL (KASBL) found at least four regions related to the resistance in the rice genome (Chr8, Chr9, Chr7, Chr11). Mapping of QTL related to Chr7 confirmed the existence of factors that were required for the resistance of Pb1 in the 22 to 23 Mbp region of the rice genome.

Conclusion

We clarified how the K209 cultivar is vulnerable to the blast disease despite possessing Pb1 and found the DNA marker responsible for the quantitative resistance of Pb1. We identified the QTL loci required for Pb1-mediated resistance to rice panicle blast. Pb1 was negatively dependent on at least three QTLs, 7, 9 and 11, and positively dependent on one, QTL 8, in the K209 genome. This finding paves the way for creating a line to select optimal QTLs in order to make use of Pb1-mediated resistance more effectively.
  相似文献   
85.
Polyphenols (PFs) extracted from green tea, known to be potent anti‐oxidants, have been reported to be effective in increasing the motility and viability of mammalian sperm, preserved in a liquid form. Therefore, we tested whether PFs might also be effective for maintaining the integrity of frozen‐thawed boar spermatozoa. Ejaculates, collected from Clawn miniature pigs, were diluted in a semen extender containing various amounts of PFs (0, 0.01, 0.05, 0.1 and 0.2% w/v) and then stored at 15°C overnight. The semen samples were processed, using the straw freezing procedure, and then frozen in liquid nitrogen. After rapid thawing at 40°C, the spermatozoa were subjected to several assays to evaluate semen quality. Spermatozoa frozen in a medium containing 0.01% w/v PFs exhibited significantly (P < 0.05) higher degrees of post‐thawed viability and acrosomal integrity than those stored in the absence of PFs. However, no change in the mitochondrial activity was noted between the two groups. The inclusion of 0.01% PFs in the semen extender was significantly (P < 0.05) effective in increasing both the rates of monospermic oocyte formation and of blastocyst formation. These findings indicate that preincubation with the semen extender, containing 0.01% PFs prior to freezing, exerts a protective effect on boar sperm by preventing injuries associated with freezing‐thawing.  相似文献   
86.
Growth‐related changes in the histochemical property and collagen architecture of the iliotibialis lateralis muscle were compared among Silky, layer and meat cockerels. Histochemical and immunohistochemical methods were employed to observe the collagen architecture. The total intramuscular collagen was also determined. The muscle consisted of type IIA, IIB and IIC myofibers, of which type IIB occurred at the highest frequency. The diameter of type IIB myofibers in each week was largest in the layer, followed by the meat, and was smallest in the Silky. The total amount of collagen reached 3.38 mg/g in the meat bird, 3.03 mg/g in the layer and 2.71 mg/g in the Silky by 30 weeks of age, respectively. In the perimysium, the collagen bundles increased in size and density of fibrils with growth. At 30 weeks of age the layer had compact collagen platelets while the Silky had loose collagen bundles. In the meat bird, the collagen bundles were moderately compact. The endomysial collagen network had a large mesh size at 1 week and thereafter accumulated many collagen fibrils to form a felt‐like fabric of fibrils at 30 weeks of age. From these results it appears that growth‐related changes in the iliotibialis lateralis muscle are not necessarily causally affected by the different growth rates of chicken breeds.  相似文献   
87.
Nicotiana benthamiana was transformed with a green fluorescent protein (GFP) gene driven by cauliflower mosaic virus 35S promoter. A GFP-silenced line and a nonsilenced line were selected after ultraviolet irradiation. GFP short-interfering RNAs (siRNAs) were detected in the silenced line but not in the nonsilenced line. T1 progeny of the silenced line varied in GFP suppression patterns and were grouped into three types (I, II, III) based on the GFP suppression pattern. With Northern blot analysis, different levels of GFP mRNA accumulated, from a very low level in type I and II to an intermediate level in type III, in contrast to a much higher level in the nonsilenced line. Plants were also inoculated with Potato virus X engineered to contain the GFP sequence to evaluate the levels of virus resistance. None to a few GFP spots were observed on inoculated leaves in types I and II, whereas numerous spots and systemic infection appeared in type III. These results showed that virus resistance was inversely correlated with the levels of mRNA, suggesting that the strength of RNA silencing determines the extent of virus resistance.  相似文献   
88.
In early January 2015–2017, anthracnose was detected on Satsuma mandarin orange (SMO) (Citrus unshiu) fruits kept in farmers’ storage rooms in Saga Prefecture, Japan. Three single-spore isolates from rotten fruits reproduced the postharvest anthracnose symptoms in wound-inoculated SMO fruits and were re-isolated from lesions. The isolates were identified as Colletotrichum fioriniae based on conidial morphology, culture characteristics, rDNA-ITS, and beta-tubulin-2 gene sequences. This is the first report of postharvest anthracnose on SMO caused by C. fioriniae.  相似文献   
89.
The first chordates appear in the fossil record at the time of the Cambrian explosion, nearly 550 million years ago. The modern ascidian tadpole represents a plausible approximation to these ancestral chordates. To illuminate the origins of chordate and vertebrates, we generated a draft of the protein-coding portion of the genome of the most studied ascidian, Ciona intestinalis. The Ciona genome contains approximately 16,000 protein-coding genes, similar to the number in other invertebrates, but only half that found in vertebrates. Vertebrate gene families are typically found in simplified form in Ciona, suggesting that ascidians contain the basic ancestral complement of genes involved in cell signaling and development. The ascidian genome has also acquired a number of lineage-specific innovations, including a group of genes engaged in cellulose metabolism that are related to those in bacteria and fungi.  相似文献   
90.
Anthocyanin pigments from rosé cider and red wine, which is a sparkling wine made from apples, were separated by gel permeation chromatography (GPC) using a TSK-GEL Toyopearl HW-40 (F) column with a 6:4 mixture of acetone and 8 M urea (pH 2.0) as the eluent. Under this condition, all phenolic compounds containing monomeric anthocyanins (mainly, cyanidin-3-galactoside; Cyn-3-gal), oligomeric and polymeric anthocyanins, chlorogenic acid, catechin, epicatechin, procyanidin B2 (PB2), and procyanidin C1 (PC1) in the apples and rosé cider were found to elute according to molecular weight. Bleaching of the anthocyanin pigments by SO(2) was gradually effective in the fractions separated by GPC according to elution volume. In the case of rosé cider, the levels of Cyn-3-gal decreased markedly during fermentation and then decreased gradually during maturation. We confirmed that anthocyanin polymers are not detectable in apple juice; these polymers are produced during fermentation and maturation as determined by GPC. The polymeric anthocyanins from red wine could be separated by this method, too.  相似文献   
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