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排序方式: 共有591条查询结果,搜索用时 15 毫秒
1.
Journal of Crop Science and Biotechnology - Two domestic wheat varieties were grown in the growth chamber set at 17°C, 20°C, 23°C and 26°C on average after the emergence of...  相似文献   
2.
Three different dietary additives were evaluated based on growth performance, innate immune responses and disease resistance in juvenile Amur catfish Silurus asotus. Four diets were prepared by supplementing 0.4% Song-gang® stone (SG), 0.05% Yucca meal (YM), 0.05% β-glucan (BG) in combination with 0.04% SG and 0.05% BG (SG + BG) to a basal commercial diet (control; CONT). Triplicate groups of fish averaging 4.95 ± 0.05 g were fed one of the test diets between 3 and 5% body weight for 8 weeks. At the end of the feeding trial, weight gain, specific growth rate, feed efficiency and protein efficiency ratio of fish fed SG and SG + BG were significantly higher than those of fish fed the BG and CONT diets (P < 0.05). Lysozyme activity in fish fed the SG, YM, and SG + BG diets was significantly higher than those of fish fed the CONT diet. Super oxide dismutase (SOD) activity was significantly higher among fish fed the SG, YM, BG and SG + BG diets than fish fed the CONT diet. After 14 days challenge test with Edwardsiella tarda, cumulative survival rates of fish fed the SG and SG + BG diets were significantly higher than those of fish fed the BG and CONT diets. Results revealed that dietary SG or SG + BG diets had positive responses over other additives in juvenile Amur catfish. However, Song-gang® stone is proposed to be a cheaper dietary additive contributing 0.04 cents/kg of feed based on economic point of view.  相似文献   
3.
Although Carnobacterium maltaromaticum has been used as a probiotic in fish, it was reported to cause disease for the first time in Korea. The objective of this study was to understand the differences between pathogenic and non-pathogenic strains. Pathogenicity was tested by challenging rainbow trout with C. maltaromaticum ATCC35586 and 18ISCm isolated from diseased fish, and DSM20342 isolated from a dairy product. We also compared 24 genomes of C. maltaromaticum strains plus the genome of our isolate 18ISCm sequenced in this study. Only the strains from diseased fish caused high mortality with severe histopathological changes. Although all strains shared more than 90% of Ko_id, wecC and xtmA were found only in strains from diseased fish. Interestingly, only strains from diseased fish harboured two wecC paralogs involved in the production of D-mannosaminuronic acid which is a major component of a well-known virulence factor, teichuronic acid. Two wecC paralogs of 18ISCm were increased when they were co-cultured with trout blood cells, suggesting that wecC genes might play a role in virulence. The results of this study show that strains isolated from diseased fish are different from strains derived from food in terms of pathogenicity to fish and the presence of virulence-related genes.  相似文献   
4.
Sargassum horneri (S. horneri), an edible brown alga, has been proposed as a functional food with an improvement effect on abnormal skin immune responses. The present study investigates the anti-allergic effect of an ethanol extract from S. horneri (SHE) on immunoglobulin E (IgE)/bovine serum albumin (BSA)-mediated activation in bone marrow-derived cultured-mast cells (BMCMCs) and passive cutaneous anaphylaxis (PCA) reaction in mice. SHE markedly and dose-dependently suppressed the degranulation of BMCMCs by reducing the β-hexosaminidase and histamine release without cytotoxicity. In addition, SHE significantly decreased the FcεRI expression on the surface of BMCMCs and its IgE binding. Moreover, SHE reduced the mRNA expression and the production of allergic cytokines; interleukin (IL)-1β, IL-4, IL-5, IL-6, IL-10, IL-13; interferon (IFN)-γ and/or tumor necrosis factor (TNF)-α; and a chemokine, thymus and activation-regulated chemokine (TARC), by suppressing the activation of Src-family kinases and nuclear factor (NF)-κB signaling. In further study, the application of SHE reduced the PCA reaction in an IgE/BSA-induced type I allergic mice model. Taken together, we suggest that SHE has an anti-allergic effect in type I allergic responses.  相似文献   
5.
This study was conducted to evaluate the effects of dietary supplementation of Barodon, an anionic alkali mineral complex, on growth, feed utilization, humoral innate immunity and disease resistance of olive flounder. A basal experimental diet was used as a control and supplemented with 0.1, 0.2, 0.3, 0.4, or 0.5% Barodon. Triplicate groups of fish (26.4 ± 0.2 g) were fed one of the diets to apparent satiation twice daily for 10 wk. The growth performance was enhanced (P < 0.05) linearly and quadratically in fish fed diets containing Barodon compared with that in fish fed the control. Feed utilization was significantly improved by Barodon supplementation. Serum lysozyme and antiprotease activities were increased quadratically in Barodon fed groups. Also, significantly higher superoxide dismutase activity was found in Barodon‐fed fish. Dietary supplementation of 0.1–0.3% Barodon resulted in significant enhancement of fish disease resistance against Streptococcus iniae. The findings in this study indicate that dietary supplementation of Barodon can enhance growth, feed utilization, innate immunity, and disease resistance of olive flounder and that the optimum level seems to be 0.1% in diets.  相似文献   
6.
Pretreatment of somatic cells with undifferentiated cell extracts, such as embryonic stem cells and mammalian oocytes, is an attractive alternative method for reprogramming control. The properties of induced pluripotent stem cells (iPSCs) are similar to those of embryonic stem cells; however, no studies have reported somatic cell nuclear reprogramming using iPSC extracts. Therefore, this study aimed to evaluate the effects of porcine iPSC extracts treatment on porcine ear fibroblasts and early development of porcine cloned embryos produced from porcine ear skin fibroblasts pretreated with the porcine iPSC extracts. The ChariotTM reagent system was used to deliver the iPSC extracts into cultured porcine ear skin fibroblasts. The iPSC extracts-treated cells (iPSC-treated cells) were cultured for 3 days and used for analyzing histone modification and somatic cell nuclear transfer. Compared to the results for nontreated cells, the trimethylation status of histone H3 lysine residue 9 (H3K9) in the iPSC-treated cells significantly decreased. The expression of Jmjd2b, the H3K9 trimethylation-specific demethylase gene, significantly increased in the iPSC-treated cells; conversely, the expression of the proapoptotic genes, Bax and p53, significantly decreased. When the iPSC-treated cells were transferred into enucleated porcine oocytes, no differences were observed in blastocyst development and total cell number in blastocysts compared with the results for control cells. However, H3K9 trimethylation of pronuclear-stage-cloned embryos significantly decreased in the iPSC-treated cells. Additionally, Bax and p53 gene expression in the blastocysts was significantly lower in iPSC-treated cells than in control cells. To our knowledge, this study is the first to show that an extracts of porcine iPSCs can affect histone modification and gene expression in porcine ear skin fibroblasts and cloned embryos.  相似文献   
7.
The effects of various buckwheat materials (buckwheat flour [BF], dietary fiber extract [DE], flavonoids extract [FE], and rutin‐enhanced flavonoids extract [REFE]) on starch digestibility and noodle‐making properties were evaluated. When FE and REFE were incorporated into noodles, the amount of rapidly digestible starch and the predicted glycemic index (pGI) were reduced. However, BF and DE did not significantly decrease the pGI value of noodles. When assessing noodle properties, hardness was increased with increasing content of buckwheat materials, whereas other texture parameters were not significantly affected by buckwheat addition. All noodles were similar in regard to water absorption and swelling index, but cooking loss was slightly increased in FE and REFE noodles. FE and REFE demonstrated higher flavonoid stability during noodle making and, additionally, were more effective at reducing starch digestibility than BF and DE. REFE, specifically, does not generate quercetin (the cause of a bitter taste), and, therefore, REFE was effective in suppressing the hydrolysis of starch in the noodles, lowering the pGI.  相似文献   
8.
Antibacterial and antifungal activity of pinosylvin, a constituent of pine   总被引:1,自引:0,他引:1  
Lee SK  Lee HJ  Min HY  Park EJ  Lee KM  Ahn YH  Cho YJ  Pyee JH 《Fitoterapia》2005,76(2):258-260
The antibacterial and antifungal activities of pinosylvin (3,5-dihydroxy-trans-stilbene), a constituent of pine, were studied and compared with those of resveratrol (3,5,4'-trihydroxy-trans-stilbene). Pinosylvin exhibited more potent growth inhibitory activity against Candida albicans and Saccharomyces cerevisiae.  相似文献   
9.
Two newly emerged begomoviruses were isolated from naturally infected tomato (Solanum lycopersicum) plants grown in greenhouses at Jeju Island and Dangjin in Korea and their genomes were characterized. These viruses-infected plants had very small leaves that curled upward, yellow margins and a leathery appearance, and a bushy and stunted appearance with short internodes. Nucleotide (nt) sequence analysis of their genomes showed that they have a DNA-A component of a monopartite begomovirus. Their genomes comprised 2763 and 2764 nucleotides with six open reading frames. The results of nt sequence similarity analysis of DNA-A genome between the two Korean isolates and isolates of Tobacco leaf curl Japan virus (TbLCJV), Honeysuckle yellow vein virus (HYVV), Honeysuckle yellow vein mosaic virus (HYVMV), and Eupatorium yellow vein virus in Japan (EpYVV) showed that they are likely similar to HYVV-[Masuda] (89.4–92.8% nt identity). Consequently, we tentatively propose the two isolates’ names as HYVV-Jeju and -DJ according to the ICTV geminivirus rules. Phylogenetic relationship analysis of 33 DNA-A genome sequences using PAUP* 4.0b10 and MrBayes revealed that HYVV-Jeju and -DJ belong to the Far East Asian begomovirus species complex. Within the Far East Asian begomovirus species complex, HYVV-Jeju and -DJ are distantly related to EpYVV, HYVMV, and TbLCJV groups. Based on the presence of a recombination fragment spanning the C3 ORF, a recombinant origin was suggested for both HYVV-Jeju and –DJ, with parents close to Japanese isolates HYVMV-[SP1:00] and Eupatorium yellow vein virus (EpYVV)-[Suya]. In addition, the presence of a further recombination fragment spanning the IR suggested the parents of HYVV-DJ were close to HYVV-Jeju and EpYVV-[Suya].  相似文献   
10.
The present study investigated the effect of fish meal (FM) replacement with fermented soybean meal (FSM) on growth and feed utilization of rainbow trout. Two FSM products, FSM1 (more fermentation with more small peptide and acid than FSM2) and FSM2 were used to replace 20%, 40% and 60% of FM in control diet (250 g/kg FM), respectively (FSM1‐20, FSM1‐40, FSM1‐60, FSM2‐20, FSM2‐40 and FSM2‐60). Then the seven diets were fed to rainbow trout (18.1 g) for 8 weeks. Weight gain (WG), feed conversion ratio (FCR) and digestibility of crude protein and dry matter showed no significant difference among the groups of FSM1‐20, FSM1‐40, FSM2‐20, FSM2‐40 and the control, but WG significantly decreased and FCR increased when 60% FM was replaced by both FSMs (p < .05). The replacement of 40%, 60% FM resulted in lower villus height than the control (p < .05), and intestinal protease activity was lower in FSM2‐40, FSM2‐60 and FSM1‐60 groups than the control group (p < .05). In addition, the activity of alkaline phosphatase and superoxide dismutase increased with increasing levels of FSM (p < .05). In conclusion, dietary fish meal could be replaced by 40% with both FSMs without adverse effects on growth and feed utilization of rainbow trout based on an eight weeks feeding trial.  相似文献   
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