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991.
MA Xu-yuan DAI Zhi-feng WANG Hui-chao YANG Jing-nan TANG Xiang-yang KANG Yu-hua DING Chun-sheng LI Yu-xia YANG Rui-lin LIN Xu-hong 《园艺学报》2018,34(5):884-892
AIM:To investigate the change of intestinal flora distribution and its relationship with interleukin-23 (IL-23)/IL-17 axis in ulcerative colitis (UC) patients. METHODS:The fresh fecal samples from 20 patients with active UC and 20 healthy controls were collected. The distribution of the flora was analyzed by direct smear and traditional bacterial culture. The changes of bacteria were detected by real-time PCR. The hemoglobin, albumin, erythrocyte sedimentation, and C-reactive protein levels were tested routinely. Both normal and damaged mucosal tissues of UC patients were examined and obtained by colonoscopy, and further assessed by Mayo scoring, Baron grading and HE staining. The expression of IL-17 and IL-23 was observed by immunohistochemistry and Western blot. RESULTS:(1) The degree of flora imbalance in active UC patients was higher than that in the healthy controls (P<0.05). (2) The results of aerobic culture showed that the number of Escherichia coli in the UC patients was significantly lower than that in the normal controls (P<0.01), while Enterococcus was increased obviously (P<0.01). The results of anaerobic culture revealed that the numbers of Bacteroidetes, Bifidobacterium bifidum and Lactobacilli in the UC patients were significantly decreased (P<0.01). (3) Quantitative analysis of target bacteria showed that the relative quantification of Escherichia coli, Bacteroidetes, Bifidobacterium bifidum and Lactobacilli in the UC patients was significantly lower than that in the normal subjects, and the number of Enterococcus was significantly increased (P<0.01). (4) Compared with control group, no significant change of hemoglobin in the UC patients was ovserved, albumin was significantly decreased (P<0.05), but erythrocyte sedimentation and C-reactive protein levels were elevated obviously (P<0.01). (5) The Mayo score, Baron grade, and histopathological score were all increased (P<0.01). (6) High IL-17 and IL-23 expression levels were detected in the UC patients (P<0.01). (7) Correlation analysis showed that the average absorbance values of IL-17 and IL-23 expression were positively correlated with Baron grade (r=0.717, P=0.02; r=0.849, P=0.016) and pathological score (r=0.660, P=0.03; r=0.675, P=0.032). Meanwhile, the average absorbance value of IL-23 expression was negatively correlated with the number of Escherichia coli (r=-0.699, P=0.025), and positively correlated with Enterococcus (r=0.872, P=0.010). Furthermore, the average absorbance value of IL-17 expression was positively correlated with Enterococcus (r=0.764, P=0.046), and both of them were not correlated with other bacteria. CONCLUSION:Obvious flora imbalance exists in active UC patients, changed intestinal microflora is closely related with the degree of inflammation. IL-23/IL-17 axis, as a key factor in the development of UC, may be related to the changes of intestinal microflora. The interaction between intestinal microflora and IL-23/IL-17 axis plays an important role in the pathogenesis of UC. 相似文献
992.
采用生长速率法,测定了咪鲜胺锰盐、福·福锌、苯醚·溴菌腈、二氢蒽醌、苯醚甲环唑和多福·溴菌腈等6种新型化学药剂对菜豆炭疽病菌的生长抑制作用。结果表明,6种化学药剂对菜豆炭疽病菌均具有抑制作用,其中80%福·福锌可湿性粉剂和10%苯醚甲环唑水分散粒剂的抑菌效果最好,浓度为1 000 mg·L~(-1)时的抑菌率分别达到了77.68%和72.96%,EC_(50)分别为212.41 mg·L~(-1)和296.83 mg·L~(-1)。因此,80%福·福锌可湿性粉剂和10%苯醚甲环唑水分散粒剂可作为田间防治菜豆炭疽病的候选药剂。 相似文献
993.
以三江平原小叶章沼泽化草甸为研究对象,采用静态箱法,研究了氮素添加对小叶章群落多样性以及CO_2排放通量的影响,以期得出群落多样性以及CO_2排放对氮沉降的响应规律。结果表明:高氮显著增加了小叶章湿地的Shannon-Wiener指数,但是低氮降低了小叶章湿地的Shannon-Wiener指数;高氮显著抑制了小叶章湿地的优势度指数,低氮也降低了小叶章湿地的优势度指数;高氮显著增加了小叶章湿地的均匀度指数,虽然低氮也增加了小叶章湿地的均匀度指数,但是差距不大。在自然对照样地中,小叶章湿地CO_2排放通量平均值为411.79mg·m~(-2)·h~(-1),而低氮样地中,小叶章湿地CO_2排放通量平均值为607.50mg·m~(-2)·h~(-1),高氮样地中,小叶章湿地CO_2排放通量平均值为608.86mg·m~(-2)·h~(-1),施氮显著增加了小叶章湿地的CO_2排放通量,但低氮与高氮处理之间差异不显著。 相似文献
994.
AIM: To explore the effect of fucoxanthin (Fu) on the growth and apoptosis of HSC-T6 cells. METHODS: HSC-T6 cells were divided into blank control group, negative control group and drug groups (treated with different concentrations of Fu). The cell viability was detected by CCK-8 assay at 24 h, 48 h and 72 h after Fu treatment. The cell cycle distribution and apoptotic rate were analyzed by flow cytometry. The protein expression of Bcl-2 and Bax were detected by Western blot. RESULTS: Compared with blank control group, the viability of HSC-T6 cells was inhibited by Fu at concentrations of 15~75 μmol/L in a dose- and time-dependent manner (P < 0.01). The cell ratio of G1 phase was significantly decreased (P < 0.01) and the cell ratio of S phase and G2 phase was significantly increased (P < 0.01) in 60 μmol/L Fu group after 24 h. The cell ratio of G1 phase was significantly decreased (P < 0.05) and the cell ratio of S phase and G2 phase was significantly increased (P < 0.05) in 15 μmol/L and 30 μmol/L Fu groups in a dose-dependent manner after 48 h. The early cell apoptotic rates and total cell apoptotic rates were significantly increased in the Fu treatment groups in a dose-dependent manner (P < 0.05). The protein expression of Bax was significantly increased in the Fu treatment groups and the protein expression of Bcl-2 was significantly decreased in 30 μmol/L and 60 μmol/L Fu groups (P < 0.05).CONCLUSION: Fu inhibits the growth of HSC-T6 cells possiblely via arresting the cell cycle at S phase and G2 phase. The apoptosis of HSC-T6 cells induced by Fu might be via down-regulating the protein expression of Bcl-2 and up-regulating the protein expression of Bax. 相似文献
995.
用原子荧光法检测家蚕体内硒的含量及其分布 总被引:3,自引:0,他引:3
硒对动物生殖发育、免疫系统具有重要功能,是动物必需微量元素。采用原子荧光法对不同系统家蚕体内硒的含量及其分布进行测定,结果显示:在喂食相同桑叶的情况下,不同系统家蚕品种幼虫体内的硒含量存在显著差异,5龄第4天的中系家蚕品种幼虫体内的硒含量明显高于日系家蚕品种,其中中系家蚕品种19-570体内的硒含量最高。对家蚕品种大造体内硒分布的研究结果表明:精巢中的硒含量明显高于其他组织,头部次之,脂肪体中的硒含量相对较低,由此推测硒在家蚕的生殖发育过程中可能发挥着重要作用。 相似文献
996.
大田常用农药对家蚕的熏蒸毒性测试 总被引:11,自引:4,他引:7
为减少粮桑混栽地区大田使用农药不当对蚕桑生产造成的损失,采用密闭熏蒸法测定了7种大田常用农药对家蚕的熏蒸毒性。在30℃环境中经过24 h,对2龄起蚕的LC50:敌敌畏0.1860 mg/m3,敌畏.毒1.3241 mg/m3,毒死蜱48.4111 mg/m3,氟腈.唑磷139.8818 mg/m3,三唑磷161.1514 mg/m3,氟虫腈208.330 mg/m3,吡虫啉333.330mg/m3时2龄起蚕仍无中毒症状。在25℃下经过24 h,对2龄起蚕的LC50:敌敌畏0.2020 mg/m3,敌畏.毒3.7282mg/m3,毒死蜱91.3669 mg/m3。结果表明:农药对家蚕的熏蒸毒性随着温度的升高而增强;敌敌畏、敌畏.毒对家蚕的熏蒸毒性最强,毒死蜱有一定的熏蒸毒性,三唑磷、氟腈.唑磷、氟虫腈、吡虫啉对家蚕的熏蒸毒性较小。 相似文献
997.
998.
树莓夏秋两季结果型品种顶峰生物学特性的研究 总被引:1,自引:1,他引:0
试验调查了树莓夏秋两季结果型品种顶峰的生长发育和开花结实特性.结果表明:品种顶峰分别在同一年的夏季和秋季两次开花结果,每年的6月下旬到7月下旬2a生枝结果即夏季结果期,果实生长发育从开花到成熟需28d,采收期近1个月,结果后枝条自然枯萎死亡;顶峰的秋季结果期为8月中旬到9月末,结果部位为1a生枝的中上部,果实生长发育需36d,采收期长达46d,采收后11月初枝条进入休眠.顶峰1a生枝的长度在6月上旬和7月上旬增加迅速,7月中旬停止增加,粗度的快速增加集中在6月上旬和7月份,8月初粗度停止增加,2a生枝的长度和粗度都不增加. 相似文献
999.
施氮量对水稻不同品种类型稻米品质的影响 总被引:19,自引:1,他引:18
2000-2001年以24个水稻品种为供试材料,水稻全生育期分别施纯氮0、100、200、300kg·hm-2,研究施氮量对水稻不同品种类型稻米品质的影响。结果表明:稻米主要品质指标在氮肥处理与品种间的差异极显著,且多数品质指标在氮肥与品种间存在极显著的互作效应。施氮量对稻米品质指标有一定的调节作用,且因品种类型而异,适当增施氮肥可改善稻米加工品质、提高胶稠度、改善营养品质,但外观品质会变劣。 相似文献
1000.
在新扬州鸡随机交配大群中,按家系随机选择不同年份的新扬州鸡2批,采用约束极大似然法对新扬州鸡早期体重遗传力进行估计。结果表明:初生和2、4、6、8周龄5个不同时期体重遗传力中等,遗传力为0.3096~0.5684,达到或接近显著水平(P<0.05);2、4、6及8周龄4个不同时期体重遗传力为0.30~0.44;初生重遗传力较高,接近0.60。 相似文献