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文中综合国内外资料,论述了几种重要的脂肪细胞因子瘦素(Leptin)、脂联素(Adiponectin)、抵抗素(Resistin)、游离脂肪酸(FFA)的最新进展。脂肪组织细胞因子是脂肪细胞分泌的一系列生物活性蛋白,其对机体脂肪组织代谢信号的传导和整合,维持机体能量的平衡具有重要作用。通过对脂肪细胞因子的研究可以开发各种增强剂或抑制剂,通过上调或下调相关的脂肪细胞因子,实现对脂肪组织代谢的定向调控,可为畜禽的优质、高效生产服务。 相似文献
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<正>干扰素(Interferon,IFN)是1957年Isaaes和Lindenmann研究流感病毒干扰现象时发现的一种细胞因子,它可以干扰病毒的复制[1]。IFN具有广谱抗病毒、抗肿瘤及免疫调节等多种生物活性,已成为免疫学、临床医学和肿瘤 相似文献
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动物细胞因子研究进展 总被引:6,自引:2,他引:4
细胞因子是免疫活性细胞和其它细胞分泌的具有多种生物活性的多肽或蛋白质 ,这些细胞因子是重要的信息传递物质 ,特别在免疫、炎症和造血系统等生物学反应过程中具有重要的作用。近几年 ,细胞因子的研究已成为生物学研究中最活跃的领域之一。新的细胞因子不断被发现 ,大量的细胞因子正在或将要应用于医学临床。细胞因子的研究带动了整个免疫学的发展。其应用展现出广阔的前景。文章简要介绍了动物细胞因子的作用及其应用前景 ,包括细胞因子与免疫抑制的关系、细胞因子在免疫增强剂和免疫治疗剂、构建新型基因工程苗以及细胞因子对于蛋白质、脂肪和葡萄糖代谢的调控作用等方面的主要研究进展 相似文献
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Lillehoj[1]等1992年试验证明,鸡脾淋巴细胞和胸腺细胞与豆蛋白A(ConA)诱导的鸡脾淋巴细胞条件培养基(conditioned medium,CM)共培养4 h和16 h后,可增强NK细胞对禽白血病病毒转化的B淋巴细胞LSSCC-KP9的杀伤活性,这与Schauenstein1982年报道的哺乳动物白细胞介素2样活性的细胞因子的生物活性相似,这表明鸡体内存在功能类似于哺乳动物IL-2的细胞因子. 相似文献
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细胞因子是免疫活性细胞和其它细胞分泌的具有多种生物活性的多肽或蛋白质,这些细胞因子是重要的信息传递物质,特别在免疫、炎症和造血系统等生物学反应过程中具有重要的作用。细胞因子用于重组疫苗上的研究已成为生物学研究中最活跃的领域之一。在基因工程疫苗研制中,常把细胞因子基因(如IL-2、IL-1等)和保护抗原基因连接在一起,构成融合蛋白.以增强疫苗的抗体产生和细胞免疫水平。以干扰素和白细胞介素为例,叙述了细胞因子在免疫增强剂和免疫治疗剂、构建新型基因工程苗等方面的主要研究进展。 相似文献
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魏静 《四川畜牧兽医学院学报》2009,(4):28-32
在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。 相似文献
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本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。 相似文献
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REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air. 相似文献
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以国际标准强毒R株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离MG,并收集感染鸡所产蛋分离MG。结果表明,人工感染48小时后上、下呼吸道及肺已被全面感染,96小时气囊已被感染,120小时输卵管已能分离到MG,卵巢始终分离不到MG。人工感染鸡自144小时便能在其所产蛋中分离出MG。药物治疗能在72小时内消除感染,油乳剂苗则需24天后逐渐降低蛋内MG分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内MG,但以研制的种蛋浸泡剂药浴效果为最好。 相似文献
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Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF
Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo. 相似文献