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排序方式: 共有4845条查询结果,搜索用时 78 毫秒
941.
Jeong Hyo Lee Jeong‐Woong Park Eun Sol Seo Hoy‐Ung Kim Seo Woo Kim Ji Seon Han Hyun Sik Jun Sung‐Jo Kim Tae Sub Park Byung‐Chul Park 《Animal Science Journal》2019,90(7):903-912
The value‐added products in livestock industry is one of the key issues in order to maximize the revenue and to create a new business model. Numerous studies have suggested application of herbal plants as feed additives to increase health, productivity, and/or high‐quality product in livestock. In this study, the first experiment was designed to develop in vitro evaluation system by using primary chicken myoblast (pCM) cells isolated from pectoralis major of 10‐day‐old male embryos. Subsequently, to evaluate effects of Korean Danggui Angelica gigas Nakai (AGN), we optimized the concentration of AGN root extract for treatment of primary pCM cells. After the treatment of AGN root extract, we compared proliferation and differentiation capacity, and also examined the gene expression. In the second experiment, the next generation sequencing analysis was performed to compare the different patterns of the global gene expression in pCM cells treated with AGN extract. Three up‐regulated (pancreas beta cells, fatty acid metabolism and glycolysis) and one down‐regulated (adipogenesis) gene sets were characterized suggesting that the AGN extract affected the metabolic pathways for the utilization of fat and glucose in chicken muscle cells. Furthermore, we validated the expression patterns of the up‐regulated genes (GCLC, PTPN6, ISL1, SLC25A13, TGFBI, and YWHAH) in the AGN‐treated pCM cells by quantitative RT‐PCR. These results demonstrated that the treatment of AGN extract decreased proliferation and differentiation of pCM cells, and affected the metabolic pathways of glucose and fatty acids. Moreover, AGN extract derived from byproducts such as stem and leaf also showed the reduced proliferation patterns on AGN‐treated pCM cells. Taken together, pCM cell‐based in vitro assay system could be primarily and efficiently applied for evaluating the biofunctional efficacy of various feed additive candidates. 相似文献
942.
Min‐Ok Ryu Byung‐Gak Kim Ul‐Soo Choi Kwan‐Hyuck Baek Young‐Ki Song Qiang Li Kyoung‐Won Seo Sandra Ryeom Hwa‐Young Youn Dong‐Ha Bhang 《Veterinary and comparative oncology》2019,17(1):99-106
Protein kinase A, a cyclic adenosine monophosphate (AMP)‐dependent enzyme, normally exists within mammalian cells; however, in cancer cells, it can leak out and be found in the serum. Extracellular cyclic AMP‐dependent protein kinase A (ECPKA) has been determined to increase in the serum of cancer‐bearing dogs. However, there have been no reports in the veterinary literature on serum ECPKA autoantibody (ECPKA‐Ab) expression in dogs with cancer. The aim of this study was to evaluate ECPKA‐Ab and C‐reactive protein (CRP) as serum biomarkers for cancer in dogs. ECPKA‐Ab and CRP levels were detected by an enzyme‐linked immunosorbent assay in serum samples from dogs with malignant tumours (n = 167), benign tumours (n = 42), or non‐tumour disease (n = 155) and from healthy control dogs (n = 123). ECPKA‐Ab and CRP levels were significantly higher in the dogs with malignant tumours than in those with benign tumours or non‐tumour diseases, as well as in the healthy controls (P < 0.001, Kruskal‐Wallis test). There was a significant positive correlation between the neoplastic index, which was developed using ECPKA‐Ab and CRP levels, and the presence of cancer in dogs (P < 0.001); the area under the receiver‐operating characteristic curve was estimated to be >0.85 (P < 0.001). In conclusion, ECPKA‐Ab is a potential serum biomarker for a broad spectrum of cancers. Combined measurement of CRP and ECPKA‐Ab levels in serum improves the sensitivity and accuracy of a diagnosis of cancer in dogs. 相似文献
943.
944.
Since the mid-1940s US sheep inventory has experienced dramatic declines, which has weakened the sheep industry significantly, making it increasingly important to analyze potential policy implications that could affect US sheep inventories in the future. Public grazing lands are often used in sheep production, especially within the western United States. The public grazing fee is, therefore, a cost within the production of sheep. A US sheep model applying capital stock inventory accounting methodology is developed to model both the supply and demand within the joint sheep and wool industries. The model is used to create a baseline projection for the next several years. Various public grazing fee policies are created to demonstrate the effects of the policies on the levels of sheep inventory and sheep and wool production within the country. Results indicate removing the public grazing fee (set at $0/animal unit month) may slow the rate of decline but would not be effective at reversing the declining trend. This suggests reducing the public grazing fee is not a viable policy option to help bring stability to the sheep and wool industries. However, projections indicate raising the grazing fee would have a substantial adverse effect on the industries. Consideration should be given to these results as grazing fee policy is adjusted moving forward. 相似文献
945.
Sung‐Eun Lee Byoung‐Ho Lee Won‐Sik Choi Byeoung‐Soo Park Jeong‐Gyu Kim Bruce C Campbell 《Pest management science》2001,57(6):548-553
The fumigant toxicity of various volatile constituents of essential oils extracted from sixteen Korean spices and medicinal plants towards the rice weevil, Sitophilus oryzae L (Coleoptera: Curculionidae), was determined. The most potent toxicity was found in the essential oil from Mentha arvensis L var piperascens (LC50 = 45.5 µl litre?1 air). GC–MS analysis of essential oil from M arvensis showed it to be rich in menthol (63.2%), menthone (13.1%) and limonene (1.5%), followed in abundance by β‐pinene (0.7%), α‐pinene (0.6%) and linalool (0.2%). Treatment of S oryzae with each of these terpenes showed menthone to be most active (LC50 = 12.7 µl litre?1 air) followed by linalool (LC50 = 39.2 µl litre?1 air) and α‐pinene (LC50 = 54.9 µl litre?1 air). Studies on inhibition of acetylcholinesterase activity of S oryzae showed menthone to have a nine‐fold lower inhibitory effect than menthol, despite menthone being 8.1‐fold more toxic than menthol to the rice weevil. Different modes of toxicity of these monoterpenes towards S oryzae are discussed. © 2001 Society of Chemical Industry 相似文献
946.
Kim NW Harley CB Prowse KR Weinrich SL Piatyszek MA Wright WE Shay JW 《Science (New York, N.Y.)》1995,268(5214):1194-1117
947.
The effects of canthaxanthin on porcine oocyte maturation and embryo development in vitro after parthenogenetic activation and somatic cell nuclear transfer
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A Taweechaipaisankul JX Jin S Lee GA Kim BC Lee 《Reproduction in domestic animals》2016,51(6):870-876
The objective of this study was to examine the effects of canthaxanthin (Cx) treatment during in vitro maturation (IVM) of porcine oocytes on embryonic development after parthenogenetic activation (PA) and somatic cell nuclear transfer (SCNT), on intracellular glutathione (GSH) and reactive oxygen species (ROS) levels in mature oocytes, and on gene expression in both PA‐ and SCNT‐derived blastocysts. To determine the optimal effective concentration of Cx, porcine oocytes were cultured in IVM medium supplemented with various concentrations (0, 20, 40 and 80 μM) of Cx for 22 hr. Compared to other groups, supplementation with 40 μM Cx significantly improved blastocyst formation rates after PA (p < .05), but no significant differences were observed among groups in total blastocyst cell numbers. Subsequently, oocytes were cultured in IVM medium supplemented with or without 40 μM Cx. Oocytes treated with 40 μM Cx showed significantly increased cleavage and blastocyst formation rates after SCNT compared to the control group (p < .05). Moreover, significantly increased intracellular GSH and reduced ROS levels were observed in the Cx‐treated group (p < .05). In addition, both PA‐ and SCNT‐derived blastocysts from the 40 μM Cx‐treated group showed significantly increased mRNA expression of Bcl2 and Oct4 and decreased Caspase3 expression level (p < .05), when compared with the control group. PA‐derived blastocysts from the 40 μM Cx‐treated group also exhibited significantly decreased expression of Bax (p < .05). Our results demonstrated that treatment with 40 μM Cx during IVM improves the developmental competence of PA and SCNT embryos. Improvement of embryo development by Cx is most likely due to increased intracellular GSH synthesis, which reduces ROS levels in oocytes, and it may also positively regulate apoptosis‐ and development‐related genes. 相似文献
948.
Effects of fenugreek seed extract supplementation on growth performance,nutrient digestibility,diarrhoea scores,blood profiles,faecal microflora and faecal noxious gas emission in weanling piglets
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M. Begum M. M. Hossain I. H. Kim 《Journal of animal physiology and animal nutrition》2016,100(6):1121-1129
This study was conducted to evaluate the effect of dietary fenugreek seed extract (FSE) on growth performance, apparent total tract digestibility (ATTD), diarrhoea scores, blood profiles, faecal microflora and faecal gas emission in weanling pigs. A total of 135 weanling pigs [(Yorkshire × Landrace) × Duroc] with an average BW of (7.96 ± 1.03 kg; 28 days of age) were used in a 42‐day study. Piglets were randomly allotted to three experimental diets with nine replicate pens and five pigs per pen. Dietary treatments were as follows: CON, basal diet; FSE1, basal diet + 0.1% FSE; FSE2, basal diet + 0.2% FSE. Pigs were fed with phase 1 (0–14 days) and phase 2 (14–42 days) diets in the form of mash. Average daily gain (ADG) was linearly increased (p = 0.031) by FSE supplementation compared with CON diet during days 0–14. From days 14–42, FSE2 diet had increased ADG and growth efficiency (G/F) compared with the CON diet (p = 0.014 and 0.026 respectively). Moreover, ADG and G/F were increased by FSE supplementation during days 0–42 (linear, p = 0.037 and 0.014 respectively). Energy digestibility was higher (linear, p = 0.030) by FSE supplementation at 6 weeks. On day 42, dietary supplementation of FSE linearly increased red blood cells (RBC) and immunoglobulin G (IgG) concentration (p = 0.042 and 0.038 respectively). Piglets fed FSE2 diet had higher (linear, p = 0.025) serum high‐density lipoprotein cholesterol (HDL‐C) concentration compared with those fed CON diet. However, piglets fed FSE2 diet had linearly reduced faecal ammonia (NH3) and hydrogen sulphide (H2S) gas emission compared with those fed the CON diet (p = 0.018 and 0.010 respectively). In conclusion, FSE supplementation increased the performance and reduced faecal gas emission in weanling pigs. 相似文献
949.
Eunseok Jeong Rommel M. Tan Hyunsuk Oh Kyungeun Kim Yeji Choi Min‐su Kim Namsoo Kim Kichang Lee 《Veterinary radiology & ultrasound》2016,57(6):E67-E70
A 9‐year‐old intact female mixed breed dog was presented for mammary gland tumor surgery, and preoperative radiographs showed a tubular soft tissue opacity mass with multifocal mineralization in the caudoventral abdominal cavity. Subsequent ultrasonography demonstrated uterine dilation with echogenic fluid and endometrial acoustic shadowing consistent with mineralization. Resection of mammary gland tumors and ovariohysterectomy were performed. Pyometra was diagnosed on cytologic examination of uterine fluid. Histopathology of the uterine tissue confirmed a diagnosis of cystic endometrial hyperplasia with uterine mineralization. 相似文献
950.
Jimo Jeong Sangjun Park Eunseok Jeong Namsoo Kim Minsu Kim Yechan Jung Youngkwon Cho Kichang Lee 《Journal of veterinary science (Suw?n-si, Korea)》2016,17(1):103-109
This study was conducted to assess time-sensitive magnetic resonance (MR) changes in canine blood using low-field MR. Arterial and venous blood samples were collected from eight healthy beagle dogs. Samples were placed in 5-mL tubes and imaged within 3 hours of collection at 1 day intervals from day 1 to day 30. The following sequences were used: T1-weighted (T1W), T2-weighted (T2W), fluid-attenuated inversion recovery (FLAIR), short tau inversion recovery (STIR), and T2-star gradient-echo (T2*-GRE). Visual comparison of the images revealed that four relatively homogenous blood clots and twelve heterogeneous blood clots developed. The margination of the clot and plasma changed significantly on day 2 and day 13. On day 2, heterogeneous blood clots were differentiated into 2 to 3 signal layers in the T2W, T1W, and especially the STIR images. Hypointense signal layers were also detected in the blood clots in STIR images, which have T2 hypo, FLAIR hypo, and T1 hyper intense signals. In all images, these signal layers remained relatively unchanged until day 13. Overall, the results suggest that hematomas are complex on low-field MRI. Accordingly, it may not be feasible to accurately characterize hemorrhages and predict clot age based on low-field MRI. 相似文献