首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 606 毫秒
1.
心脏体外循环系统检测植物外啡肽活性的研究   总被引：3，自引：0，他引：3  
本文利用猪胃蛋白酶在37℃条例下降解中盘粉，采集不同反应时间的酶解液样品，低温离心处理后，分别加入蛙心体外循环系统中，测定心肌收缩力变化，并随即加入阿片肽阻断剂-纳洛酮，检测植物外啡肽活性。结果表明，酶解液能够引起心肌收缩力加强，并可被纳洛酮逆转，证明酶解液具有植物外啡肽活性。  相似文献   

2.
采用过瘤胃保护技术使饲料中的小麦蛋白避开山羊瘤胃微生物破坏作用,进入皱胃和小肠降解,产生活性肽,增强对山羊生长代谢的调节作用。建立了蛙心体外循环系统,利用外啡肽特异阻断剂—纳洛酮,生物检测不同消化液中植物外啡肽的活性。结果表明:对照期和试验期相比24h采食青草量分别为4 65±0 231,6 413±0 039kg,差异极显著(P≤0 001);血清类胰岛素生长因子 1(IGF 1)分别为153 647±18 670,223 993±19 450ng/ml,差异极显著(P<0 01)。血清生长激素(GH)23 170±0 891,26 792±1 003ng/ml,差异极显著(P<0 01)。血清胰岛素18 103±1 035,23 983±1 600ng/ml,差异极显著(P<0 01)。血清氨基氮0 102±0 003,0 140±0 004mM/ml,差异极显著(P<0 001)。血清氨氮0 206±0 012,0 086±0 006mM/ml,差异极显著(P<0 001)。蛋白过瘤胃保护后的皱胃液以及未保护的瘤胃液能使心肌收缩力显著增强,加入纳洛酮后心肌收缩力都显著性逆转降低,从而证明这些消化液具有较强的外啡肽活性。表明蛋白质过瘤胃保护技术能够有效地增强植物外啡肽对生长代谢的调控作用。  相似文献   

3.
麦谷蛋白源外啡肽B5来源于麦谷蛋白酶解产物,具有阿片样活性。作者通过进一步优化化学合成工艺制备外啡肽B5,并将其添加到传染性支气管炎病毒(IBV)H120株灭活疫苗中,免疫后21d(35日龄)采用IBV M41株病毒液进行点眼、滴鼻攻毒。通过测定免疫仔鸡的生产性能、淋巴细胞增殖水平、血清抗体水平、临床症状及组织病理学变化等指标,评价外啡肽B5的应用效果。结果显示,经过化学合成工艺优化后获得了高纯度的外啡肽B5(HPLC浓度大于98%),7~35日龄肉鸡的平均体增重试验组比对照组显著提高13.8%,料肉比试验组比对照组显著降低15.1%;同时一定浓度的外啡肽B5能够诱导肉仔鸡产生较强的淋巴细胞增殖反应(P0.01),免疫鸡群抗体水平显著高于对照组,在IBV M41株攻毒试验中,试验组可以显著减轻病毒感染肉仔鸡临床症状,肺和肾无组织病理学变化,免疫保护率达到96.7%。外啡肽B5可望开发成一种新型动物功能性饲料添加剂或动物疫苗佐剂。  相似文献   

4.
将24头仔公猪分为对照组(正常哺乳28 d断奶)、试验I组(添喂β-酪啡肽-7)和试验Ⅱ组(添喂酪蛋白酶解物)。试验组于21 d断奶,再连续添喂酪蛋白胃蛋白酶解液或β-酪啡肽-7 10 d,每天2次(共20mL),至32 d,3组动物各随机取6头同时剖杀,取血、胃食糜和空肠食糜。通过所建立的RP-HPLC方法,在胃食糜和空肠食糜中检测到β-酪啡肽-5、β-酪啡肽-7样物质。对照组、酪啡肽-7组和酪蛋白水解液组,β-酪啡肽-7的平均含量分别为21.12±2.38,23.58±7.49、21.81±9.93μg/g胃食糜和16.99±3.48、19.08±2.85、21.36±4.85μg/g肠食糜;胃食糜中-βCM-7的含量高于空肠食糜,试验组均高于对照组。在各组仔猪的血液中未检测到酪啡肽样物质。肠食糜的细胞生物学试验结果表明:与喂仔猪料的对照组比较,试验I组和试验Ⅱ组对细胞腺苷酸环化酶的活性均具有不同程度的抑制作用,抑制率分别为27.9%和89.0%,抑制作用均能被纳洛酮反转,逆转率分别是43.2%和89.07%。提示在21日龄断奶仔猪饲料中添加酪啡肽或酪蛋白酶解物,其肠道中有酪啡肽释放,阿片总活性升高。  相似文献   

5.
蛋白发酵产物外啡肽的构成与活性研究   总被引：1，自引：0，他引：1  
利用人工瘤胃装置,选用经定向培育的瘤胃细菌体外发酵面筋蛋白,并适时提取发酵液进行了植物外啡肽构成与活性的研究。结果显示体外发酵11h,外啡肽的生物学活性最强,肽浓度也相对较高。以超滤结合纸层析法检测外啡肽的构成,所显示的色带表明为10～27肽。人工瘤胃装置的发酵参数pH6.412±0.207、总脱氢酶活性(TDHA)(1.037±0.045)U/mL,D600(细胞菌生长量)1.410±0.065,氨氮(NH3-N)(1318.36±140.68)mg/L,微生物总蛋白(MCP)(6.213±1.014)g/L。采用所制备的植物外啡肽对AA肉鸡肌肉注射不同剂量,同时注射新城疫疫苗,结果显示,试验组新城疫血凝抑制抗体滴度显著性高于对照组,7～35日龄的体增重也显著高于对照组,血清中生长激素(GH)、胰岛素(Ins)、三碘甲腺原氨酸(T3)、四碘甲腺原氨酸(T4)的浓度也显著高于对照组。每周每公斤体质量2mL的外啡肽剂量肌肉注射效果最好。  相似文献   

6.
建立并优化以雄蚕蛾蛋白粉为原料酶解制备活性肽的工艺技术,有助于研发具有功能活性的雄蚕蛾保健产品。首先以雄蚕蛾蛋白的水解度和肽得率为考核目标,对酶解工艺中的酶解液p H、反应温度、反应时间、酶种类及其配比、料液质量浓度及酶用量等因素进行单因素试验。然后采用Box-Benhnken中心组合试验设计法对酶解条件进行优化,建立p H、温度、时间、料液质量浓度等4个因素的酶解效率预测回归模型,并使用Design-Expert 8.0软件对数据做回归分析,验证试验结果提示建立的雄蚕蛾蛋白酶解效率预测回归模型对实测数据有较好的拟合性。最终确定以Alcalase蛋白酶和丹尼斯克碱性蛋白酶对雄蚕蛾蛋白粉进行联合酶解的最佳工艺条件为:酶解液p H 9.5,反应温度55℃,反应时间130 min,料液质量浓度70 g/L。在此优化工艺条件下,雄蚕蛾蛋白粉的水解度为27.32%,肽得率为50.43%,酶解效率综合值为40.47%。  相似文献   

7.
本文概述了酶解酪蛋白生产生物活性肽的研究现状及开发趋势,提出了当前通过酶解酪蛋白制备活性肽需要进一步解决的问题,并探讨了酪蛋白源活性肽开发趋势。  相似文献   

8.
本研究以米渣为原料,通过对米渣进行预处理及限制性酶解后,再对酶解液浓缩后喷雾干燥得到米蛋白肽粉,研究其最佳酶解条件及产物性质.结果表明:(1)最佳酶解工艺条件:用酶量为1%,酶解温度为50℃,固液比为1:5,pH值为8,酶解时间3 h;(2)产物米蛋白肽的蛋白质含量为91.5%,分子质量大部分在3000 Da 以下,短肽含量为77.87%,必需氨基酸含量丰富,是一种优质植物蛋白质资源.  相似文献   

9.
《畜牧与兽医》2016,(12):68-71
本试验旨在探讨β-酪啡肽-7对早期断奶仔猪胃酸分泌的影响及其可能机制。选取刚出生健康仔公猪24头,随机分为对照组和β-酪啡肽-7处理组,其中β-酪啡肽-7处理组仔猪在饲喂与对照组相同日粮的基础上,每天灌胃β-酪啡肽-7溶液。仔猪21日龄时一次性断奶,分别在21日龄和35日龄时屠宰,颈部采血分离血清、取胃肠内容物、胃底组织等,测定胃肠食糜的p H值、胃蛋白酶活性、血清中胃泌素的含量以及胃底组织中H~+-K~+-ATP/Na~+-K~+-ATP酶的活性。结果显示:β-酪啡肽-7能降低断奶仔猪胃内食糜p H,其中显著降低35日龄断奶仔猪的胃内p H值(P0.05),而对十二指肠、空肠以及回肠食糜p H无显著影响;β-酪啡肽-7能够升高21日龄断奶仔猪胃蛋白酶的活性,差异不显著(P0.05),但其能显著上调35日龄仔猪的胃蛋白酶的活性(P0.05);放射免疫分析法检测胃泌素结果显示:灌胃β-酪啡肽-7后仔猪血清中胃泌素含量均高于对照组,21日龄时差异不显著(P0.05),35日龄时极显著升高(P0.05);灌胃β-酪啡肽-7对断奶仔猪H~+-K~+-ATP/Na~+-K~+-ATP酶的活性作用不显著(P0.05)。说明添加β-酪啡肽-7可以有效缓解断奶应激引起的胃酸分泌不足以及胃蛋白酶活性较低等问题,其作用途径可能是通过促进胃泌素分泌实现的。  相似文献   

10.
建立伴大豆球蛋白酶解产生抑菌肽的最适条件,对酶解产物进行分离纯化后进一步测定其抑菌活性。采用复合风味蛋白酶水解伴大豆球蛋白,测定不同时间的酶解液对大肠杆菌和金黄色葡萄球菌的抑菌活性。结果显示:2 h水解产生的酶解肽具有抑菌活性,其对大肠杆菌和金黄色葡萄球菌的最小抑菌浓度分别是2.6和3.2 mg/mL。2 h水解液经Sephadex-G15分离纯化,采用平板计数法鉴定各组分。结果显示:CP2组分对大肠杆菌具有显著的抑制作用(P<0.05)。本研究证明伴大豆球蛋白的复合风味蛋白酶酶解肽具有一定的抑菌活性。  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.
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   

14.
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   

15.
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   

16.
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   

17.
The purpose of this study was to determine the frequency of different tumor types within a large cohort of cats with intracranial neoplasia and to attempt to correlate signalment, tumor size and location, and survival time for each tumor. Medical records of 160 cats with confirmed intracranial neoplasia evaluated between 1985 and 2001 were reviewed. Parameters evaluated included age, sex, breed, FeLV/FIV status, clinical signs, duration of signs, number of tumors, tumor location(s), imaging results, treatment, survival times, and histopathologic diagnosis. Most of the cats were older (11.3 +/- 3.8 years). Primary tumors accounted for 70.6% of cases. Metastasis and direct extension of secondary tumors accounted for only 5.6 and 3.8% of cases, respectively. Twelve cats (7.5%) had 2 or more discrete tumors of the same type, whereas 16 cats (10.0%) had 2 different types of intracranial tumors. The most common tumor types were meningioma (n = 93, 58.1%), lymphoma (n = 23, 14.4%), pituitary tumors (n = 14, 8.8%), and gliomas (n = 12, 7.5%). The most common neurological signs were altered consciousness (n = 42, 26.2%), circling (n = 36, 22.5%), and seizures (n = 36, 22.5%). Cats without specific neurological signs were common (n = 34, 21.2%). The tumor was considered an incidental finding in 30 (18.8%) cats. In addition to expected relationships (eg, meninges and meningioma, pituitary and pituitary tumors), we found that lesion location was predictive of tumor type with diffuse cerebral or brainstem involvement predictive of lymphoma and third ventricle involvement predictive of meningioma.  相似文献   

18.
The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.  相似文献   

19.
The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.  相似文献   

20.
Infectious diseases have always been a terrible scourge for humans. The appearance of these plagues, as they were called without distinction, was generally connected to various conditions: asters, climatic changes or religious reasons. The concept of contagious, and then infectious, diseases came slowly. Variolation, i.e. transmission of ‘virulent’ matter to induce a natural disease and the immunity against it, was brought from Constantinople to England by Lady Montague, in 1721. This ‘variolation’ technique was also often performed in veterinary medicine against diseases like sheep-pox or pleuropneumonia. As ‘vaccination’ is the term generally accepted for ‘immunisation’, variolation can be the word designating such a technique. The second period of the history of immunisation began, in 1880, with the studies of Pasteur and his collaborators. A great number of bacterial vaccines were developed: dead, live but attenuated or only parts of pathogens. The viruses were produced in animals, then in eggs and at last, in tissue cultures. Second generation vaccines appeared with genetic engineering: recombinant vaccines, vector vaccines, nucleic acids vaccines, and markers vaccines, among others. These novel technologies can permit the development of new ones and improve the quality of the vaccines already existing.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号