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排序方式: 共有2222条查询结果,搜索用时 921 毫秒
911.
Chun-Ying Li Dong-Sik Park Se-Ra Won Soon-Kwan Hong Jin-Kwan Ham Jae-Keun Choi Hae-Ik Rhee 《Journal of Cereal Science》2008
Phytic acid inhibits mineral absorption in the intestines of monogastric animals, inhibition which can contribute to public health problems in human populations. This research compared the nutritional properties of parent rice cultivar Il-pum with those of an Il-pum-derived, mutant low-phytate rice cultivar, Sang-gol. No significant differences were shown in moisture, fat, carbohydrate and mineral content between Il-pum and Sang-gol. In the composition of protein and fatty acid, there were also no differences between the two cultivars. In the nutritional aspects, though Sang-gol had a 50% lower phytate content than Il-pum, the total phosphorus contents in the two cultivars were shown to be similar. These results indicated that Sang-gol had similar nutritional properties to those of the parent cultivar Il-pum, with the added benefit of lower phytate content. 相似文献
912.
Jang IC Park JH Park E Park HR Lee SC 《Plant foods for human nutrition (Dordrecht, Netherlands)》2008,63(4):205-210
The Cosmos bipinnatus has been used in a traditional herbal remedy for various diseases such as jaundice, intermittent fever, and splenomegaly.
The present study describes the preliminary evaluation of antioxidant activities and antigenotoxic effect of Cosmos bipinnatus flowers according to four different colors (white, pink, orange, and violet). The antioxidants properties were evaluated by determining TPC, DPPH RSA, ABTS RSA, and RP. The highest TPC of methanolic
CFE (at concentration of 1 mg/ml) showed in violet colored CF (1,013 μM), and IC50 of DPPH RSA, ABTS RSA, and RP were also the lowest in violet colored CFE with values of 0.61, 1.48, and 0.82 mg/ml, respectively.
The antigenotoxic effect of the CFE on DNA damage induced by H2O2 in human leukocytes was evaluated by Comet assay. Pretreatments with CFE produced significant reductions in oxidative DNA
damage at the concentration of 500 μg/ml, except for violet colored CFE. The ED50 value of white colored CFE has shown the highest inhibition (0.40 mg/ml) on H2O2 induced DNA damage, followed by orange > pink > violet color. These results suggested that Cosmos bipinnatus has significant antioxidant activity and protective effect against oxidative DNA damage. 相似文献
913.
The synthesis of a series of phthalimide based azo disperse dyes and their spectral properties were investigated. The azo
dyes containing phthalimide and N-methyl phthalimide structure in diazo component were synthesized in order to compare their spectral properties. The synthesized
dyes developed the color of yellow to violet and the N-substitution of the phthalimide gave a bathochromic effect on the color change. Most of the synthesized dyes exhibit negative
solvatochromism so that the absorption band of dyes moves toward shorter wavelengths as the polarity of the solvent increases.
In the case of halochromic effect, the bathochromic shift decreased steadily with the general electron donating capacity of
the substituents in the coupling component, and became negative especially when more powerful electron donating groups are
present in the coupling components ring. 相似文献
914.
The free modulation of interlayer distance in a layered high-transition temperature (high-Tc) superconductor is of crucial importance not only for the study of the superconducting mechanism but also for the practical application of high-Tc superconducting materials. Two-dimensional (2D) superconductors were achieved by intercalating a long-chain organic compound into bismuth-based high-Tc cuprates. Although the intercalation of the organic chain increased the interlayer distance remarkably, to tens of angstroms, the superconducting transition temperature of the intercalate was nearly the same as that of the pristine material, suggesting the 2D nature of the high-Tc superconductivity. 相似文献
915.
A resistant phenotype similar to that conferred in wheat by the complementary genes Lr27 + Lr31 was produced in the progeny of intercrosses of cultivars carrying Lr27 and a line possessing Lr12 . This confirms that Lr12 is either completely linked with Lr31 or is the same gene. On the basis of these findings and that Lr31 is located on chromosome 4BS, it is concluded that Lr12 must also be located on 4BS. Adult-plant genetic tests confirm that the Australian wheat cultivar Timgalen carries Lr12 , and stocks with Lr12 alone were established from this cultivar. 相似文献
916.
This study determined the haematological changes in Korean catfish, Silurus asotus , experimentally infected with Edwardsiella tarda . Twenty-four or 48 h after infection with 1 × 104 colony-forming units (CFU) mL−1 of E. tarda , the fish were anaesthetized and the blood was collected. The haematological and biochemical tests included haematocrit (Ht), haemoglobin (Hb), leucocyte counts (Lc), total calcium (Ca), total protein (TP) concentration, alkaline phosphatase (ALP), glucose (GLU), aspartate aminotransferase, lysozyme and differential leucocyte populations. After 24- and 48-h infection, the values of Ht, Hb, Lc, TP, ALP and GLU were significantly decreased with respect to the control. Aspartate aminotransferase and lysozyme activity in both the 24- and 48-h groups exhibited higher levels compared with those in the control. However, the bacterial infection did not induce any significant alteration in the Ca concentration. After the 48-h infection, neutrophils and macrophage populations were reduced whereas lymphocytes were increased with respect to those in the control and the 24-h infection groups. The present study demonstrates that E. tarda infection causes haemato-biochemical responses that are related to the general physiological condition and defence system in catfish. 相似文献
917.
The optimum dietary docosahexaenoic acid level based on growth and non‐specific immune responses in juvenile rock bream,Oplegnathus fasciatus
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Jeongwhui Hong Seunghan Lee Hyeonho Yun Mohammad Moniruzzaman Youngjin Park Erfan Shahkar Minji Seong Sungchul C Bai 《Aquaculture Research》2017,48(7):3401-3412
A feeding trial was conducted to determine the optimum level and effect of incremental dietary levels of docosahexaenoic acid (DHA, 22:6n‐3) on growth and non‐specific immune responses in juvenile rock bream, Oplegnathus fasciatus. A basal diet without DHA supplementation was used as a control, and six other diets were prepared by supplementing with 4, 8, 12, 16, 20 or 40 g kg?1 DHA. These diets included no eicosapentaenoic acid and/or arachidonic acid contents. The actual DHA concentrations of the diets were 1, 4.8, 8.9, 13.1, 17.6, 21.2 and 41.4 g kg?1 diet (DHA1.0, DHA4.8, DHA8.9, DHA13.1, DHA17.6, DHA21.2 and DHA41.4 respectively). At the end of feeding trial, final body weight, weight gain, specific growth rate and feed efficiency of fish fed the DHA13.1, DHA17.6, DHA21.2 and DHA41.4 diets were significantly higher than those fed the other diets (P < 0.05). The broken‐line analysis of weight gain indicates that the optimum dietary DHA level is 11.9 g kg?1. Fish fed DHA1.0 had the highest hepatosomatic index, an increase in plasma cholesterol, triglyceride, low‐density lipoprotein and aspartate aminotransferase levels, as well as a decrease in high‐density lipoprotein. Superoxide dismutase activity of fish fed DHA13.1 and DHA17.6 diets was significantly higher than that of fish fed DHA1.0, DHA4.8 and DHA8.9 diets. Fish fed the DHA17.6, DHA21.2 and DHA41.4 diets showed significantly higher lysozyme activity than those fish fed DHA1.0, DHA4.8 and DHA8.9 diets. Therefore, the optimum dietary DHA level could be greater than 11.9 g kg?1 but less than 13.1 g kg?1 in diet. 相似文献
918.
Seung-Hwi Lee Min-Chul Lee Jayesh Puthumana Jun Chul Park Sujin Kang Jeonghoon Han Kyung-Hoon Shin Heum Gi Park Ae-Son Om Jae-Seong Lee 《Fisheries Science》2017,83(5):725-734
We have used the cyclopoid copepod Paracyclopina nana to understand responses to the temperature shift. To determine the changes of molecular mechanisms, which would lead to physiological changes in P. nana, we investigated mRNA expression involved in lipogenesis, the area of lipid droplets, the ratio of fatty acids, and life parameters (growth and fecundity) in response to temperature changes (15, 20, and 30 °C) with comparative control at 25 °C. Setting the temperature 25 °C as a standard point, there were increases in mRNA expression, the area of the lipid droplets, and fatty acid composition at temperatures below the standard (15 °C), while all the markers mentioned above significantly decreased at higher temperatures than the standard (25 °C). Through fecundity and growth rate experiments, daily nauplii production was reduced and growth retardation was observed at both 15 and 20 °C, but no noticeable differences in the two parameters were observed at 30 °C compared to the control (25 °C). This study provides a better understanding of the effects of temperature on lipogenesis in copepods. 相似文献
919.
Hye-Won Yang Seyeon Oh Dong-Min Chung Minyoung Seo Shin Jae Park You-Jin Jeon Kyunghee Byun BoMi Ryu 《Marine drugs》2022,20(5)
The in vitro capacity of Ishige okamurae extract (IO) to improve impaired muscle function has been previously examined. However, the mechanism underlying IO-mediated muscle protein metabolism and the role of its component, Ishophloroglucin A (IPA), in mice with dexamethasone (Dexa)-induced muscle atrophy remains unknown. In the present study, we evaluated the effect of IO and IPA supplementation on Dexa-induced muscle atrophy by assessing muscle protein metabolism in gastrocnemius and soleus muscles of mice. IO and IPA supplementation improved the Dexa-induced decrease in muscle weight and width, leading to enhanced grip strength. In addition, IO and IPA supplementation regulated impaired protein synthesis (PI3K and Akt) or degradation (muscle-specific ubiquitin ligase muscle RING finger and atrogin-1) by modulating mRNA levels in gastrocnemius and soleus muscles. Additionally, IO and IPA upregulated mRNA levels associated with muscle growth activation (transient receptor potential vanilloid type 4 and adenosine A1 receptor) or inhibition (myostatin and sirtuin 1) in gastrocnemius and soleus muscle tissues of Dexa-induced mice. Collectively, these results suggest that IO and IO-derived IPA can regulate muscle growth through muscle protein metabolism in Dexa-induced muscle atrophy. 相似文献
920.
Dennis Kaw Gomez Gun Wook Baeck Ji Hyung Kim Casiano Hermopia Choresca Se Chang Park 《Journal of veterinary diagnostic investigation》2008,20(1):38-44
Viral nervous necrosis (VNN) is a worldwide disease affecting several species of cultured marine fish. In Korea, VNN has been identified in several species of cultured marine fish. In this study, the authors present data of the amplified nested polymerase chain reaction product (420 bp) of 21 nodavirus strains from different species of apparently healthy wild marine fish on the southern coast of Korea. Phylogenetic analysis based on the partial nucleotide sequence (177 bases) of the RNA2 coat protein gene of 21 strains was highly homologous (93-100%) and closely related to that of the known betanodavirus, redspotted grouper nervous necrosis virus. These results indicate that betanodaviruses occur in large populations of wild marine fish in the southern part of the Korean peninsula, suggesting the importance of these subclinically infected fish as an inoculum source of betanodavirus that is horizontally transmitted to susceptible cultured fish species. 相似文献