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101.
102.
Sei-Ichi Okumura Katsutoshi Arai Yoshitaka Harigaya Hirotaka Eguchi Mizuho Sakai Hiroaki Senbokuya Suehiro Furukawa Kunio Yamamori 《Fisheries Science》2007,73(2):237-243
ABSTRACT: In order to develop a highly efficient method for mass production of triploid Pacific abalone Haliotis discus hannai , caffeine treatment that is safe and inexpensive was optimized. To suppress the first meiotic division, fertilized eggs were exposed to either a 10- or 15-mM caffeine solution for 24 min beginning at 12 min after fertilization. In most treated batches, the rates of cleaved eggs showed no significant difference from the control batches. However, in most treated batches, the rates of occurrence of normal larvae and the survival rates of the early juveniles were significantly lower than those of the controls. The triploid rates at 6 days to 11 months after settlement in all the treated batches were extremely high (91–100%). There was no significant difference in the mean triploid rates between 10- and 15-mM caffeine treatments. These results suggest that both treatment conditions were conducive to triploid abalone production. One live 2n/3n mosaic specimen was found in the treated batches. However, since the frequency of mosaic was extremely low, the mosaicism would probably not have an adverse effect on the stable production of triploid abalones. 相似文献
103.
104.
Sato Y Tsubono Y Nakaya N Ogawa K Kurashima K Kuriyama S Hozawa A Nishino Y Shibuya D Tsuji I 《Public health nutrition》2005,8(3):309-314
OBJECTIVE: Adequate fruit and vegetable intake has been suggested to protect against colorectal cancer. However, several recent prospective studies have reported no association. We therefore examined the association between fruit and vegetable intakes and the risk of colorectal cancer in a prospective cohort study in Japan. DESIGN: Between June and August 1990, 47 605 Japanese men and women completed a self-administered questionnaire, including a food-frequency questionnaire. We divided the subjects into quartiles based on their self-reported fruit and vegetable consumption. There were 165 colon cancer and 110 rectal cancer incidences identified during 7 years of follow-up, to the end of December 1997. We used Cox proportional hazards models to estimate the relative risk (RR) of developing colorectal cancer according to the level of fruit and vegetable consumption, applying adjustments for potential confounders. RESULTS: No statistically significant association was observed between fruit and vegetable consumption and the risk of colorectal cancer. The multivariate RR of colon cancer in the highest quartile of fruit and vegetable intake compared with the lowest was 1.13 (95% confidence interval (CI) 0.73-1.75), the RR for vegetables alone was 1.24 (95% CI 0.79-1.95) and that for fruit alone was 1.45 (95% CI 0.85-2.47). The corresponding multivariate RRs for rectal cancer were 1.12 (95% CI 0.67-1.89), 1.14 (95% CI 0.67-1.93) and 1.41 (95% CI 0.73-2.73). CONCLUSIONS: We found no association between the consumption of fruit and vegetables and the risk of colorectal cancer among the Japanese population. 相似文献
105.
Isolation and identification of DPPH radical scavenging compounds in Kurosu (Japanese unpolished rice vinegar) 总被引:7,自引:0,他引:7
Shimoji Y Tamura Y Nakamura Y Nanda K Nishidai S Nishikawa Y Ishihara N Uenakai K Ohigashi H 《Journal of agricultural and food chemistry》2002,50(22):6501-6503
Dihydroferulic acid (DFA) and dihydrosinapic acid (DSA) were isolated from Kurosu (unpolished rice vinegar) as the major constituents responsible for Kurosu's radical scavenging activity. The levels of antioxidative activity of DFA and DSA in DPPH radical scavenging were higher than those of their respective structurally related compounds, ferulic acid and sinapic acid. The concentrations of DFA and DSA were low in common rice vinegar (polished rice vinegar), suggesting that Kurosu is more advantageous than rice vinegars as an antioxidative food item. As the concentrations of DFA and DSA were low in unpolished rice, too, these acids are thought to be produced in Kurosu through the process of the fermentation from ferulic acid and sinapic acid, respectively. 相似文献
106.
Terasawa N Saotome A Tachimura Y Mochizuki A Ono H Takenaka M Murata M 《Journal of agricultural and food chemistry》2007,55(10):4154-4159
Zuiki, a stalk of taro (Colocasia esculenta), is a traditional vegetable in Japan. Raw zuiki is often boiled and vinegared to eat. The surface color of zuiki is reddish. Here, we isolated a red pigment from zuiki and identified it as cyanidin 3-rutinoside using instrumental analyses. The color of zuiki disappeared by boiling, but the zuiki turned red again in an acetic acid solution. It seems that the cyanidin 3-rutinoside that exists on the surface of zuiki elutes in boiling water and then, the pigment that seeps out from the inside of the zuiki is exposed to an acid solution, and its surface turns red again. The radical scavenging activity of purified zuiki anthocyanin was 114 mg equivalent to BHT/g. About half of the anthocyanin in fresh zuiki was washed out by boiling, and the radical scavenging activity of zuiki was definitely reduced. 相似文献
107.
Takuya Kubo Tsuyoshi Kobayashi Kyoko Kato Seiichi Nishimura Shigeru Uemura Kiyomi Ono Akihiro Sumida Toshihiko Hara 《Agricultural and Forest Meteorology》2008,148(8-9):1293-1304
In order to more accurately evaluate the functional activity of forest stands by canopy production and evapotranspiration, we improved the methods for field measurements and statistical modeling to estimate foliage configuration (spatial distribution of leaves) while simultaneously reconstructing the three-dimensional photosynthetically active photon flux density (PPFD) distribution (PPFD pattern) in a forest canopy. By using a sensor (photodiode) array, a PPFD pattern was observed in summer 2002 under the canopy in an even-aged, pure stand of Japanese mountain birch Betula ermanii Cham. (17-years old) in Hokkaido, northern Japan. A Markov chain Monte Carlo (MCMC) sampling technique is developed such that a set of foliage configurations generated by the model referred to as the Gibbs foliage canopy (GFC) approximates the field-measured PPFD pattern. The posterior distribution of the foliage configurations is generated by the parallel tempering MCMC of eight independent series of foliage configurations. The GFC model generated the posterior distribution of the LAI estimates (mean 4.56) that appeared to be appropriate in comparison to other LAI estimates of the B. ermanii stand based on the indirect and nondestructive methods by LAI-2000 (LAI = 3.43) and litterfall traps (LAI = 5.56) because they could be under- and overestimated, respectively. Our evaluations of the canopy production and evapotranspiration rates suggest that the relationship between LAI and canopy functions was not very simple because it depended on the nonlinear functional forms of the leaf responses of photosynthesis and transpiration to PPFD. The current study demonstrates an application of MCMC techniques that can generate a set of possible structures of unobserved/unobservable objects based on the high-resolution dataset obtained by some indirect (or remote-sensing) methods. 相似文献
108.
Saito Y Itagaki S Otsuka Y Kobayashi Y Okumura H Kobayashi M Hirano T Iseki K 《Journal of agricultural and food chemistry》2005,53(15):6100-6104
In clinical, patients usually take many kinds of drugs at the same time. Thus, drug-drug interactions involving transporters can often directly affect the therapeutic safety and efficacy of many important drugs. However, there have been few studies on food-drug interactions involving transporters. Dietary polyphenols have been widely assumed to be beneficial for human health. Polyphenols are found ubiquitously, and they are commercially prepared and used as functional foods. We have reported that ferulic acid, which is one of the most well-known polyphenols and is used as a functional food, affected the transport of nateglinide, an antidiabetic drug, by Caco-2 cells. In this study, we investigated the effects of other polyphenols on the nateglinide/H(+) transport system. We report here that caffeic acid and p-coumaric acid have a different inhibitory manner on the uptake of nateglinide. The results of this study are useful to identify the substrate specificity of the nateglinide/H(+) cotransporter. 相似文献
109.
稻鸭共生对鸭肉品质和屠宰性能的影响 总被引:3,自引:0,他引:3
以云南麻鸭为试验材料,分别在稻鸭共生(稻鸭组)和常规网上平养(常规组)两种饲养模式下饲养至体重达1.8 kg,测定其常规肉品质和部分屠宰性能.结果表明:①两组间鸭肉失水率、嫩度、熟肉率、肉色亮度值和红度值无显著差异(P>0.05);稻鸭组的pH值显著高于常规组(P<0.05);肉色黄度值B极显著高于常规组(P<0.01).②两组间屠宰率、半净膛率、全净膛率、胸肉率差异不显著(P>0.05);稻鸭组的皮脂厚、腹脂率比常规组分别降低了18.52%、11.76%(P<0.05);腿肉率提高了11.40%(P<0.05).③稻鸭组的生长速度明显慢于常规组. 相似文献
110.
Long‐term selection using a single trait criterion,non‐destructive deformation,in White Leghorns: Effect over time on genetic parameters for traits related to egg production 下载免费PDF全文
Olivier Gervais Keijiro Nirasawa Christian E. Vincenot Yoshitaka Nagamine Kazuyuki Moriya 《Animal Science Journal》2017,88(2):222-230
Although non‐destructive deformation is relevant for assessing eggshell strength, few long‐term selection experiments are documented which use non‐destructive deformation as a selection criterion. This study used restricted maximum likelihood‐based methods with a four‐trait animal model to analyze the effect of non‐destructive deformation on egg production, egg weight and sexual maturity in a two‐way selection experiment involving 17 generations of White Leghorns. In the strong shell line, corresponding to the line selected for low non‐destructive deformation values, the heritability estimates were 0.496 for non‐destructive deformation, 0.253 for egg production, 0.660 for egg weight and 0.446 for sexual maturity. In the weak shell line, corresponding to the line selected for high non‐destructive deformation values, the heritabilities were 0.372, 0.162, 0.703 and 0.404, respectively. An asymmetric response to selection was observed for non‐destructive deformation, egg production and sexual maturity, whereas egg weight decreased for both lines. Using non‐destructive deformation to select for stronger eggshell had a small negative effect on egg production and sexual maturity, suggesting the need for breeding programs to balance selection between eggshell traits and egg production traits. However, the analysis of the genetic correlation between non‐destructive deformation and egg weight revealed that large eggs are not associated with poor eggshell quality. 相似文献