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131.
本试验旨在研究发酵前后芹菜汁的主要功能成分变化和芹菜发酵液对葡聚糖硫酸钠(DSS)诱导的小鼠溃疡性结肠炎(UC)的防治及免疫调节作用。选取50只4周龄雄性C57BL/6小鼠随机分为空白组、模型组及低、中、高浓度芹菜发酵液组,每组10只。按10 μL/g BW的剂量标准给空白组和模型组小鼠灌胃无菌生理盐水,其他组小鼠则灌胃不同浓度的芹菜发酵液,持续7 d。从第8天开始,除空白组自由饮用无菌水外,其余组连续7 d自由饮用3% DSS溶液;在此过程,每日称量体重,进行疾病活动指数(DAI)评分。在第14天,通过摘眼球取血法获得全血,随后脱颈处死小鼠,解剖取出结肠组织测量长度并通过苏木素-伊红(HE)染色法制作病理切片,进行病理学分析。以流式细胞仪分选技术检测外周血中CD4+/CD8+T淋巴细胞比值,以酶联免疫吸附法(ELISA)检测血清中肿瘤坏死因子-α(TNF-α)、白细胞介素-6(IL-6)、γ-干扰素(IFN-γ)和IL-10的含量。结果表明:①芹菜汁经发酵后,总酸、总糖、总多酚、类黄酮、维生素C和超氧化物歧化酶(SOD)等多种活性成分的含量均显著增加(P<0.05)。②与模型组相比,芹菜发酵液高浓度组能减少DSS引起的小鼠体重损失(P<0.01)、结肠缩短(P<0.01)和DAI降低(P<0.05)。③组织病理学分析结果表明,各发酵液组的UC症状均得到不同程度改善,肠腺结构相对完整,杯状细胞轻微减少,仅有少量淋巴细胞和中性粒细胞浸入。④流式细胞仪分析结果显示,相较于模型组,发酵液组全血CD4+/CD8+T淋巴细胞比值极显著升高(P<0.01)。⑤ELISA检测结果显示,与模型组相比,芹菜发酵液组的IL-6、TNF-α和IFN-γ含量极显著下调(P<0.01),IL-10的含量极显著上调(P<0.01)。综上,芹菜汁经发酵后主要功能活性成分均得到显著提高,并且发酵芹菜液对DSS诱导的小鼠UC具有一定的防治和免疫调节作用,其作用机制可能与维持外周血中CD4+与CD8+T淋巴细胞平衡,以及抑制促炎症因子(TNF-α、IL-6和IFN-γ)表达,促进抗炎症因子(IL-10)表达有关。 相似文献
132.
Piero ADDIS Alberto ANGIONI Viviana PASQUINI Angelica GIGLIOLI Valeria ANDREOTTI Stefano CARBONI Marco SECCI 《Integrative zoology》2021,16(2):138-148
Mussels close their shell as a protective strategy and the quantification of this behavioral marker may represent an alarm signal when they are exposed to environmental stressors. In the present study, we investigated the ability of the Mediterranean mussel Mytilus galloprovincialis to recover and then the resilience or inertia of valve activity after a pulsing exposition to diverse levels of salinity (5, 10, 20, and 35 PSU as reference value). The trial simulated an event of drastic and sudden reduction of seawater salinity thus mimicking an event of flash flood from intense rain. Valve gaping and movements were measured in continuous cycle for 10 days using a customized magneto-electric device which uses Hall sensors. Results showed that under normal conditions of salinity (35 PSU), the general pattern of valve movements was a continuously open state with sporadic spikes indicating a closing motion. At salinity of 5, PSU mussels reacted by closing their valves, leading to a 77% mortality on the 4th day. At salinity of 10, PSU animals were observed with closed valves for the entire duration of the exposure and no mortality occurred, they showed a significant reduction in the valve activity once the reference value of salinity was re-established. In contrast, salinity of 20 PSU did not trigger a significant behavioral response. Interestingly, there no define rhythms of valve movements were recorded during salinity challenges. 相似文献
133.
综述了非离子表面活性剂对反刍动物瘤胃微生物数量、酶活性、瘤胃发酵特性、饲料消化率和生产性能等方面的影响作用以及与其他饲料添加剂的互作效应,并就其作用机制进行了阐述。 相似文献
134.
WANG Lei LV Yang ZHANG Yue XIE Jia-qian ZHAO Di YAN Li-qiong MEI Hui-min WANG Lei YI Dan CHEN Hong-bo DING Bin-ying HOU Yong-qing WU Tao 《中国畜牧兽医》2016,43(5):1355-1360
The probiotics tested in the experiment were isolated from the intestinal of weaning piglets.The isolated probiotics and E.coli K88 were inoculated into the culture of intestinal porcine epithelial cell-1 (IPEC-1).The activity of lactate dehydrogenase (LDH) in the supernatant was measured after incubating for 2.5 h.At the same time, the probiotics and E.coli K88 were co-cultured in vitro, the number of E.coli K88 was counted and the probiotics which could be resistant to the E.coli K88 were selected 2.5 h later.The results showed that the Lactobacillus casei and Bacillus coagulans could significantly reduce LDH activity (P<0.05), decrease the damage of E.coli K88; Bacillus coagulans could inhibit the growth of E.coli K88.At the same time, Bacillus coagulans could resist high temperature, acid and bile salt.The results showed that Bacillus coagulans strains had great potential as the application of probiotics strains.The methods could be used as a model of screen probiotics which could inhibit the growth of E.coli K88 in vitro. 相似文献
135.
Effect of Age,Season, Body Condition,and Endocrine Status on Serum Free Cortisol Fraction and Insulin Concentration in Horses 下载免费PDF全文
136.
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138.
Brito LF Barth AD Rawlings NC Wilde RE Crews DH Mir PS Kastelic JP 《Domestic animal endocrinology》2007,33(1):1-18
The objective of the present study was to characterize the effects of nutrition on circulating concentrations of metabolic hormones, gonadotropins, and testosterone during sexual development in bulls. Nutrition regulated the hypothalamus-pituitary-testes axis through effects on the GnRH pulse generator in the hypothalamus and through direct effects on the testes. Pituitary function (gonadotropin secretion after GnRH challenge) was not affected by nutrition. However, nutrition affected LH pulse frequency and basal LH concentration during the early gonadotropin rise (10-26 weeks of age). There were close temporal associations between changes in insulin-like growth factor-I (IGF-I) concentrations and changes in LH pulse frequency, suggesting a role for IGF-I in regulating the early gonadotropin rise in bulls. The peripubertal increase in testosterone concentration was delayed in bulls with lesser serum IGF-I concentrations (low nutrition), suggesting a role for IGF-I in regulating Leydig cell function. Serum IGF-I concentrations accounted for 72 and 67% of the variation in scrotal circumference and paired-testes volume, respectively (at any given age), indicating that IGF-I may regulate testicular growth. Bulls with a more sustained elevated LH pulse frequency during the early gonadotropin rise (high nutrition) had greater testicular mass at 70 weeks of age relative to the control group (medium nutrition), despite no differences in metabolic hormone concentrations after 26 weeks of age. Therefore, gonadotropin-independent mechanism regulating testicular growth might be dependent on previous gonadotropin milieu. 相似文献
139.
为评价宽缨酮(EN)对棉铃虫的生物活性, 采用浸渍叶碟法和饲料混毒法, 以印楝素为对照, 检测宽缨酮对棉铃虫的拒食及抑制生长发育活性。结果表明, 宽缨酮和印楝素的拒食中浓度分别为12.04 μg/mL和21.62 μg/mL, 宽缨酮的拒食活性优于印楝素。以含10 μg/g宽缨酮的饲料饲喂棉铃虫幼虫, 在第10~12天幼虫体重相比对照分别下降87.90%、88.04%和80.74%, 并推迟5 d化蛹, 蛹重降低。化蛹率、羽化率和卵的孵化率分别比对照下降了26.00、37.39和14.98百分点, 蛹和成虫的畸形率分别是对照的2.89倍和3.33倍。综上所述, 宽缨酮对棉铃虫具有明显拒食和抑制生长发育活性, 具有开发成为新型植物源杀虫剂的潜力。 相似文献