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1.
肌肽是存在于动物机体组织中的二肽,具有多功能的抗氧化活性.本文综述了肌肽的提取方法及其抗氧化特性.  相似文献   

2.
肌肽的提取及其抗氧化特性   总被引:5,自引:0,他引:5  
肌肽是存在于动物机体组织中的二肽,具有多功能的抗氧化活性。本文综述了肌肽的提取方法及其抗氧化特性。  相似文献   

3.
肌肽的抗氧化特性及其作用机理   总被引:5,自引:0,他引:5  
肌肽(β-丙氨酰-L-组氨酸)是存在于动物机体组织中的水溶性二肽,具有多功能的抗氧化性质。本又综述了肌肽的抗氧化特性及其作用机理。  相似文献   

4.
肌肽是由β-丙氨酸与L-组氨酸组成的一种水溶性二肽,主要存在于动物肌肉和神经组织。肌肽具有螯合金属离子、缓冲细胞酸碱度、降低脂质和蛋白的氧化损伤、调节炎症反应等多种生理功能。目前肌肽在人类疾病治疗、保健、抗衰老和化妆品等领域已有广泛应用。肌肽甲基化产物为鹅肌肽和鲸肌肽,肌肽及其衍生物合称组氨酸二肽,其中肌肽和鹅肌肽是养殖动物体内组氨酸二肽主要的存在形式,得到了畜禽和水产领域持续的研究关注。肌肽作为功能性饲料添加剂具有提高动物抗氧化能力、肌肉品质等作用,并在很多情况下提高了动物生长性能。特就肌肽的主要生理功能及其在动物养殖中的应用做一综述。  相似文献   

5.
选用1日龄健康AA肉鸡400只,随机分成4组,Ⅰ~Ⅳ组在饮水中分别添加肌肽0、20、40、60mg/L,试验期6周,研究肌肽对肉鸡抗氧化功能的影响。于每周末每组随机抽取6只鸡采血,测定血清中超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GSH-Px)的活力和丙二醛(MDA)的含量。结果表明:与未添加组比较,肌肽各剂量组可显著提高血清中SOD、CAT、GSH-Px的活性,显著降低血清MDA含量。由此得出,肉鸡摄入肌肽可以提高机体的抗氧化功能。  相似文献   

6.
肌肽对CCl_4诱导的肝匀浆脂质过氧化的抑制作用   总被引:4,自引:1,他引:4  
肌肽是一种天然的水溶性二肽,以较高的浓度存在于有氧代谢最活跃的肌肉和脑中。由β-丙氨酸和L-组氨酸在肌肽合成酶的作用下合成。近几年来的研究表明,肌肽作为一种天然二肽,具有广泛的抗氧化性能,如通过缓冲生理pH的能力,减少因体系pH值变化而产生的脂质过氧化;具有捕捉羟自由基、单线态氧和过氧自由基的作用等在体内发挥抗氧化功效,具有广泛的细胞保护作用。  相似文献   

7.
肌肽是由β-丙氨酸和L-组氨酸组成天然活性二肽,可螫合过渡金属离子,具有抗氧化及抗衰老等生物学活性,其游离氨基羧基及咪唑氮可有效接纳质子或羟基,稳定溶液pH等。就肌肽活性的生化基础及应用研究作一综述。  相似文献   

8.
组氨酸的生理功能及在动物生产中的应用   总被引:2,自引:0,他引:2  
组氨酸是组成机体蛋白质的氨基酸之一,同时也是动物合成肌肽和鹅肌肽等功能性二肽的前体物质。饲料中适量添加组氨酸可改善动物生产性能,增加肌肉肌肽含量,增强机体抗氧化能力。本文综述了组氨酸的来源和代谢、生理功能、营养需要量及在动物生产中的应用,以期为组氨酸在畜牧生产中科学应用提供参考。  相似文献   

9.
本研究旨在探究外源添加左旋肌肽对中华田园犬生长性能、血清生化指标及抗氧化能力的影响。试验选取3月龄左右的健康中华田园犬24只,随机分为4组,每组6只,单圈饲养,1只为1个重复。对照组(C组)饲喂基础饲粮,试验组在基础饲粮中分别添加300(Ⅰ组)、600(Ⅱ组)和900 mg/kg(Ⅲ组)左旋肌肽。预试期为7 d,正试期为28 d。试验开始每周进行感官评价并测定生长性能,在试验第24天进行连续5 d的消化代谢试验,试验第28天采集5 mL左右血清样本,用于测定血清生化指标、免疫功能和抗氧化能力相关指标,最后进行D-木糖吸收试验,用于测定肠道吸收功能。结果表明:1)中华田园犬平均日增重(ADG)和平均日采食量(ADFI)都与左旋肌肽添加量成反比;随着左旋肌肽添加量的增加,犬感官评分值逐渐升高,Ⅲ组的评分值显著高于其他组(P0.05)。2)犬的粪便评分值,Ⅱ组的平均得分最接近于最佳的粪便评分;随左旋肌肽添加量的增加,机体对粗脂肪的表观消化率升高;Ⅱ组和Ⅲ组粗蛋白质和粗纤维表观消化率显著高于C组(P0.05)。3)各试验组血清胆固醇(CHO)含量均显著低于C组(P0.05);Ⅰ组的血清谷草转氨酶(AST)活性显著高于C组(P0.05);Ⅱ组血清免疫球蛋白A(IgA)、免疫球蛋白G(IgG)含量显著高于C组和Ⅰ组(P0.05);Ⅲ组血清丙二醛(MDA)含量显著低于C组(P0.05),Ⅲ组血清肌酐(CRE)含量显著低于C组(P0.05),血清总抗氧化能力(T-AOC)、谷胱甘肽过氧化物酶(GSH-Px)和超氧化物歧化酶(SOD)活性均显著高于C组(P0.05)。综上可知,饲粮中添加左旋肌肽可以提高中华田园犬感官评分,增强消化吸收功能,降低血清CHO的含量,提高免疫力和抗氧化能力;饲粮中左旋肌肽添加量以600 mg/kg为最佳。  相似文献   

10.
肌肽是继超氧化物歧化酶(SOD)和维生素E后又一被发现的天然非酶促自由基清除剂和抗氧化剂,具有抗氧化、抗自由基、抗衰老及增强免疫力等生理功能。为了探讨肌肽对免疫系统的影响,本文应用不同浓度(20、40和60mg/L)的肌肽通过饮水研究了不同日龄(7、14、21、28、35和42日龄)肉鸡免疫器官的变化。结果表明:在整个试验期实验组肉鸡法氏囊小结数量增多,淋巴细胞排列由疏松至紧密,黏膜皱襞体积增大,尤其是应用40mg/L剂量组上述变化明显;与对照组相比,在21日龄时应用60mg/L肌肽组胸腺小体的数量最多,淋巴细胞排列最为紧密;应用20mg/L肌肽试验组在21日龄时脾小结的数量增多,脾动脉淋巴鞘周围壁变厚,尤其是应用60mg/L计量组上述变化更为明显。表明肌肽能够促进肉鸡免疫器官(胸腺、法氏囊和脾)的早期发育和免疫应答能力,从而提高了机体的抵抗力。  相似文献   

11.
试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。  相似文献   

12.
Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia.  相似文献   

13.
14.
1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.  相似文献   

15.
Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.  相似文献   

16.
Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded.  相似文献   

17.
Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.  相似文献   

18.
Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.  相似文献   

19.
The objective of this report was to characterize 20-year changes in proportion of calcium oxalate (CaOx) calculi and struvite calculi in dogs, and associations with breed, age, and sex. In this retrospective study, results of analysis of urinary calculi from dogs were reviewed for specimens received between July 1, 1981, and December 31, 2001. Breed, sex, age, year of submission of the specimen, and mineral type(s) were analyzed statistically. CaOx or Struvite or both were contained in 18,966 of 20,884 (91%) specimens. For both sexes, a 20-year statistically significant increase was observed in the proportion of calculus specimens that contained CaOx. The increase in this proportion was greater in females (1% to 31%) than in males (18% to 82%). From 1998 to 2001, when proportions may have plateaued, the odds of specimens containing CaOx were markedly higher in 18 breeds, markedly lower in 5 breeds, and not significantly different in 13 breeds compared with crossbreds. For both sexes, a 20-year statistically significant decrease was observed in the proportion of calculus specimens that contained struvite. This decrease in proportion was greater for males (79-16%) than for females (97-68%). From 1998 to 2001, when proportions plateaued, the odds of calculi containing struvite were markedly lower in 20 breeds, markedly higher in 1 breed, and not significantly different in 15 breeds when compared with crossbreds. Breed, age, and sex were associated statistically with CaOx or struvite urolithiasis. In conclusion, there appears to have been a long-term increase in the proportion of specimens of canine urinary calculi that contain CaOx as well as a long-term decrease in the proportion of specimens of calculi that contain struvite for both male and female dogs. The rate of change appeared to begin leveling off in the period 1998 to 2001. The recent proportion of dogs with either CaOx- or struvite-associated urolithiasis may depend on breed, age, and sex, and on interactions among these 3 factors.  相似文献   

20.
<正>1.INTRODUCTION Ensuring transportation network security is one Of the most daunting challenges confronting homeland security agencies today.Significant research has been dedicated.To model and analyze the vulnerability of transportation systems,while notably fewer studies propose specific strategies for deploying defensive technologies to safeguard these systems.  相似文献   

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