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81.
Effects of feeding lycopene isomers to laying hens on egg qualities such as lycopene concentration and color of the yolk were investigated. Firstly, to evaluate the dietary transfer of lycopene to egg yolk, (all‐E)‐lycopene–rich diets (lycopene content, 100, 200, or 300 mg/kg diet) were fed to hens for 21 days. Lycopene in egg yolk could be detected after 4 days or more from the start of feeding, and the lycopene concentration increased according to the feed amount and period. Even though most of the dietary lycopene was the all‐E‐isomer, more than 65% of lycopene in egg yolk was present as Z‐isomers. Thus, the effect of lycopene Z‐isomer content in the diet (lycopene content, 200 mg/kg diet; lycopene Z‐isomer content, 35.1% or 61.3%) on egg qualities was investigated. As the Z‐isomer content increased, the lycopene concentration in the egg yolk increased, for example, when fed a diet rich in Z‐isomers (61.3%), the lycopene concentration in the egg yolk was approximately three times higher than when fed the (all‐E)‐lycopene–rich diet for 21 days. The results indicated that Z‐isomers of lycopene had higher bioavailability and/or higher transfer efficiency to the egg yolk than the all‐E‐isomer.  相似文献   
82.
Fatty acid composition is an important indicator of beef quality. The objective of this study was to search the potential candidate region for fatty acid composition. We performed pool‐based genome‐wide association studies (GWAS) for oleic acid percentage (C18:1) in a Japanese Black cattle population from the Hyogo prefecture. GWAS analysis revealed two novel candidate regions on BTA9 and BTA14. The most significant single nucleotide polymorphisms (SNPs) in each region were genotyped in a population (n = 899) to verify their effect on C18:1. Statistical analysis revealed that both SNPs were significantly associated with C18:1 (p = .0080 and .0003), validating the quantitative trait loci (QTLs) detected in GWAS. We subsequently selected VNN1 and LYPLA1 genes as candidate genes from each region on BTA9 and BTA14, respectively. We sequenced full‐length coding sequence (CDS) of these genes in eight individuals and identified a nonsynonymous SNP T66M on VNN1 gene as a putative candidate polymorphism. The polymorphism was also significantly associated with C18:1, but the p value (p = .0162) was higher than the most significant SNP on BTA9, suggesting that it would not be responsible for the QTL. Although further investigation will be needed to determine the responsible gene and polymorphism, our findings would contribute to development of selective markers for fatty acid composition in the Japanese Black cattle of Hyogo.  相似文献   
83.
为了回顾过去,把握未来,中文简单回顾和比较了中日两国林业发展的道路的各自长短,并为加强合作的必要性和可能性提出了一些直观的看法。  相似文献   
84.
It is important to conserve forest-dependent organisms not only in broadleaved forests but also in plantation forests. We examined how surrounding forest areas affect forest bird assemblages inhabiting conifer plantations and broadleaved forests in a rural landscape in central Japan. Surrounding forest areas were measured separately as plantation area and broadleaved forest area within 200 m of each sampling site. We used hierarchical partitioning to analyze the effects of surrounding forest areas and stand structures (stand height and understory coverage) on the occurrence of four species groups. We especially focused on mature forest users that are most sensitive to loss of broadleaved forests. Occurrence of mature forest users inhabiting plantation sites was positively affected both by plantation area and broadleaved forest area whereas the occurrence of mature forest users inhabiting broadleaved forests was affected by stand height only. These results suggest that surrounding forest areas were more important to mature forest users in plantations than in broadleaved forests. To conserve mature forest users, increasing surrounding forest areas are important in plantations whereas increasing stand heights would be effective in broadleaved forests.  相似文献   
85.
We developed a high-performance liquid chromatography-based method for simultaneous analysis of nine catechins, gallic acid, strictinin, caffeine, and theobromine in green tea by using catechol as an internal standard. Although the high cost and instability of the catechin reference standards limit the application of this method, the addition of ascorbic acid to the standard stock solution preserved the stability of the reference standards in the solution for 1 year when stored at -30 degrees C. Furthermore, we found that the slopes of the calibration curves plotted were stable for a run time of 2000 h. Our method proved to be appropriate for quantification and yielded good correlation coefficients, detection levels, repeatability, reproducibility, and recovery rates. Quantitative data revealed that the contribution of only 200 mL of brewed tea to the total dietary catechins was approximately 220-420 mg, while that of 500 mL of bottled tea was approximately 170-900 mg.  相似文献   
86.
Optimization of the solid-phase extraction cleanup procedure enabled the GC-MS analysis of acrylamide in tea samples without the interference of bromination by tea catechins. Although polyvinylpolypyrrolidone (PVPP) is available for removing tea catechins from tea extract, the peaks derived from PVPP had the same retention time as brominated acrylamide in mass chromatograms obtained by GC-MS. A considerable amount of acrylamide was formed at roasting temperatures of > or =120 degrees C; the highest acrylamide level was observed when tea samples were roasted at 180 degrees C for 10 min. Higher temperatures and longer processing times caused a decrease in the acrylamide content. Furthermore, an analysis of 82 tea samples showed that rather than the reducing sugar content, the asparagine content in tea leaves was a significant factor related to acrylamide formation in roasted products. The acrylamide level in roasted tea products was controlled by asparagine in the presence of reducing sugars.  相似文献   
87.
Rendezvous of the Japanese spacecraft Hayabusa with the near-Earth asteroid 25143 Itokawa took place during the interval September through November 2005. The onboard camera imaged the solid surface of this tiny asteroid (535 meters by 294 meters by 209 meters) with a spatial resolution of 70 centimeters per pixel, revealing diverse surface morphologies. Unlike previously explored asteroids, the surface of Itokawa reveals both rough and smooth terrains. Craters generally show unclear morphologies. Numerous boulders on Itokawa's surface suggest a rubble-pile structure.  相似文献   
88.
We developed retrotransposon-based insertional polymorphism (RBIP) markers based on the long terminal repeat (LTR) sequences of copia-like retrotransposon Ppcrt4 and flanking genome sequences, which were derived from 454 sequencing data from Japanese pear (Pyrus pyrifolia) ‘Hosui’. Out of 40 sequences including both LTR and flanking genome regions, we developed 22 RBIP markers and used them for DNA profiling of 80 pear cultivars: 64 Japanese, 10 Chinese (Pyrus ussuriensis) and 6 European (Pyrus communis). Three RBIP markers were enough to differentiate ‘Hosui’ from the other Japanese pear cultivars. The 22 RBIP markers could also distinguish 61 of the 64 Japanese pear cultivars. European pears showed almost no amplification of the 22 RBIP markers, which might suggest that retrotransposons had transposed during Asian pear evolution or reflect the genetic relationship between Asian and European pears. Sixteen of the RBIP markers could be positioned on a genetic linkage map of ‘Hosui’. The RBIP loci were distributed in 10 linkage groups, and some loci were very closely located within the same linkage group. The information obtained will be applicable to developing cultivar-specific RBIP marker sets in plants.  相似文献   
89.
Floral scent attracts pollinators. We investigated the floral scent compounds recognized by pollinators in six Brassica crop species, including allogamous species with different genomes and autogamous species with two parental genomes and radish (Raphanus sativus). Biologically active compounds recognized by honeybees were screened from all floral compounds by combined gas chromatography–electroantennogram analysis and their profiles were determined by gas chromatography–mass spectrometry. Fourteen of the 52 compounds were active. All accessions had more than two active compounds, but the compounds greatly differed between the two genera. On the basis of similarities in whether active compounds were presence or absence, their amount and their composition ratio, we divided the Brassica accessions into three to five groups by cluster analyses. Most groups were composed of a mixture of allogamous and autogamous species sharing same genome, indicating that the variation depended on genome, not species. These results suggest that all species require pollinator visits for reproduction, despite their different reproductive systems. However, the inter-genus and intra-specific variations shown by the multiple groups within a species might cause different visitation frequencies by pollinators between genera and among accessions within a species, resulting in insufficient seed production in some accessions or species.  相似文献   
90.
Seven-week-old male Lewis rats received a single intraperitoneal injection of N-ethyl-N-nitrosourea (ENU) (100, 200, 400 or 600 mg/kg), and retinal damage was evaluated 7 days after the treatment. Sequential morphological features of the retina and retinal DNA damage, as determined by a TUNEL assay and phospho-histone H2A.X (γ-H2AX), were analyzed 3, 6, 12, 24 and 72 hr, 7 days, and/or 30 days after 400 mg/kg ENU treatment. Activation of the nuclear enzyme poly (ADP-ribose) polymerase (PARP) was analyzed immunohistochemically by poly (ADP-ribose) (PAR) expression in response to DNA damage of the retina. All rats that received ≥ 400 mg/kg of ENU developed retinal degeneration characterized by the loss of photoreceptor cells in both the central and peripheral retina within 7 days. In the 400 mg/kg ENU-treated rats, TUNEL-positive signals were only located in the photoreceptor cells and peaked 24 hr after ENU treatment. The γ-H2AX signals in inner retinal cells appeared at 24 hr and peaked at 72 hr after ENU treatment, and the PAR signals selectively located in the photoreceptor cell nuclei appeared at 12 hr and peaked at 24 hr after ENU treatment. However, degeneration was restricted to photoreceptor cells, and no degenerative changes in inner retinal cells were seen at any time points. Retinal thickness and the photoreceptor cell ratio in the central and peripheral retina were significantly decreased, and the retinal damage ratio was significantly increased 7 days after ENU treatment. In conclusion, ENU induced retinal degeneration in adult rats that was characterized by photoreceptor cell apoptosis through PARP activity.  相似文献   
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