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61.
LIN Xu-hong LI Yong-yu FENG Ya-jing CAO Ming-hua XU-Jing LI Kun FENG Jia-yan YU Liang-ying 《园艺学报》2012,28(6):1082-1090
AIM: To investigate the therapeutic effects and related mechanisms of two new cannabis preparations, O-1602 and cannabidiol (CBD), on lipopolysaccharide (LPS)-induced rodent models of intestinal motility disorder in vivo and in vitro. METHODS: The animal model of intestinal motility disorder was induced by intraperitoneal injection of LPS in mice. The gastrointestinal transit was measured by gavaging charcoal marker. Western blotting was applied to evaluate the protein expression of G-protein-coupled receptor 55 (GPR55). Meanwhile, the levels of tumor necrosis factor α (TNF-α) and interleukin 6 (IL-6) were tested by ELISA to assess the inflammatory degree. Smooth muscle strips from the rat and mouse ileum were incubated with LPS in vitro to establish motility disorder, and both the spontaneous contraction and electrically-evoked contraction were recorded using the organ bath technique. The traditional intracellular microelectrode technique was used to record the changes of membrane potential of smooth muscle cells. The method of determining phosphorus content was applied to assay the Ca2+-ATPase activity in smooth muscle tissues. RESULTS: In vivo, LPS resulted in significant inflammation and the disorder of gut movement (P<0.01). Pretreatment with CBD decreased both the level of IL-6 (P<0.01) and the expression of GPR55 (P<0.01), and further improved the motility of gut movement (P<0.05). O-1602 and CBD selectively normalized LPS-induced spontaneous and electrically-evoked contraction disorder of intestinal smooth muscle strips of rats and mice in vitro (P<0.05 or P<0.01), but they had no effect on the membrane potential of the smooth muscle cells both in normal and pathophysiological states. CBD also decreased the elevated Ca2+-ATPase activity in smooth muscle tissues induced by LPS (P<0.05). CONCLUSION: In vivo, CBD shows protective effect on LPS-induced intestinal motility disorder by reducing inflammation and down-regulating GPR55 expression. O-1602 and CBD counterbalance LPS-induced intestinal motility disorder to some extent in vitro, and the possible mechanism may be involved in regulating the Ca2+-ATPase activity of smooth muscle tissues, but not including the change of membrane potential. 相似文献
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63.
【目的】分析丁香假单胞菌3个致病变种基因组内简单重复序列(simple sequence repeats,SSR),为病菌SSR标记开发和遗传多样性研究提供有用信息。【方法】基于公共的基因组数据库资源,对3个菌株的完全重复SSR和不完全重复SSR的丰度和组成类型等进行分析。【结果】3个菌株完全重复SSR的分布规律较为相似,其中单碱基的短重复SSR均占绝对优势,多碱基和长重复SSR则较少;菌株B728a、1448A和DC3000的不完全重复SSR总数也较相近,分别为562、529和567,其中数量最多的均为六碱基重复。但3个菌株以四、五和六碱基为基序的SSR在基序组成和数量上则表现出较高的变异性,完全重复SSR中,除AGCC、ACCTGC等基序在两个菌株中同时出现,绝大多数基序仅在单个菌株基因组内出现;不完全重复SSR中,部分基序如CCCTG、ACGCA等的出现频率在不同菌株间存在明显差异。【结论】3个菌株的不完全重复SSR在数量和结构类型上均具有较大的相似性,而菌株间的完全重复SSR在数量和组成上则存在一定差异。 相似文献
64.
WEI Xu-hong ZANG Ying WANG Jing XIN Wen-jun GONG Qing-juan LI Yu-ying ZHANG Tong LI Yong-yong LIU Xian-guo 《园艺学报》2009,25(4):719-724
AIM: To test the possibility that TNF-α can induce the display of nociceptive behaviors in rats without any injury. METHODS: The induction of changes in 50% paw withdrawal threshold and paw withdrawal latency by peri-sciatic administration of recombinant rat TNF-α (rrTNF) was determined with the methods of behavioral tests. PDTC (a NF-κB inhibitor) was also intrathecally delivered before or after the administration of rrTNF. RESULTS: We found that peri-sciatic administration of rrTNF at the concentrations of 10, 100, and 1 000 ng/L (daily for 2 d) induced mechanical allodynia and thermal hyperalgesia in bilateral hindpaws, lasting for around 20 d. Intrathecal administration of PDTC 30 min before each peri-scitic administration of rrTNF completely prevented the decrease in bilateral thresholds, and delayed the decrease of paw withdrawal latencies. In contrast, the same dose of PDTC had no effect on mechanical allodynia when applied intrathecally 6 d after the first administration of rrTNF, while inhibited thermal hyperalgesia for about 7 d. CONCLUSION: Without any nerve injury, peri-sciatic administration of recombinant rat TNF-α at low doses produces mechanical allodynia and thermal hyperalgesia in bilateral hindpaws. NF-κB pathway may play different roles in mechanical allodynia and thermal hyperalgesia. 相似文献
65.
报道了正丁基黄原酸钠与硝酸镉形成的二维网状聚合物 [Cd(S2 CO -n -C4H9) 2 ]n 的合成与结构。该配合物属单斜晶系 ,空间群P2 (1) /c,晶胞参数 :a =2 .5 6 4 9(4)nm ,b=0 .5 810 (7)nm ,c=1.1348(41)nm ,β=10 1.70 1(2 ) 0 ,V =1.6 5 6 6 (4)nm3 ,Z =4 ,Dc =1.6 4 7mg/m3 ,F(0 0 0 ) =82 4 ,R1=0 .0 711,wR2 =0 .175 5。 相似文献
66.
简要回顾和评述了力学在桥梁工程中的应用及发展,说明了力学在桥梁工程发展过程中的地位、作用,并对今后的应用前景作了展望。 相似文献
67.
考虑到HIV-1感染过程中免疫反应和非线性感染函数,建立了一类具有三个分布时滞的HIV-1感染动力学模型.得到了关于病毒感染的基本再生数R0和CTLs免疫反应的基本再生数R1<R0. 通过构造Lyapunov泛函证明了系统具有阈值动力学性质,即当R0≤1时,系统存在全局渐近稳定的无感染平衡点; 当R1≤1<R0时,系统出现一个全局渐近稳定的无免疫应答感染平衡点; 当R1>1时,系统出现一个全局渐近稳定的免疫应答感染平衡点. 相似文献
68.
以甲苯-2,4-二异氰酸酯、丙烯酸羟丙酯、丁二酸酐、超支化聚酯为原料,合成了一种新型可紫外光固化的水性超支化聚氨酯丙烯酸酯(Water-soluble hyperbranched polyurethane acrylate,WHPUA),采用傅里叶变换红外光谱分析了其合成过程中基团的变化,并对WHPUA系列水分散体水溶性质进行了研究.结果表明,随着单个分子中羧基含量的增加,WHPUA水溶性增大,黏度升高,表面张力降低,粒径减小;随着超支化聚酯代数的增加,WHPUA粒径增加;羧基中和度的增加有利于增加预聚物表面的羧基离子的密度,从而使WHPUA的粒径减小,体系的黏度也随之降低. 相似文献
69.
沈阳地区冬小麦和水稻复种的可行性试验简报 总被引:1,自引:0,他引:1
在沈阳地区,采用在冬麦北移育种中形成的冬麦品种9625作为复种前茬,以及成熟期较短的水稻品系87913和黑糯1号作为下茬进行麦稻复种可行性研究。结果表明,在沈阳地区麦稻复种是可行的。分析认为麦后复种水稻的产量比一季单作小麦的产量高,同时提高了经济效益,增加了耕地和光能利用率,提高了土地生产力。并提出上下茬搭配的作物栽培管理的各项措施。同时分析了在沈阳地区发展麦稻复种的限制性因素。 相似文献
70.
剪切失效是强动载荷作用下结构失效的重要模式,从自由梁在中点受到质量块撞击后发生剪切失效的无量纲判据的分析表明,在初始速度间断面上是否发生剪切失效取决于质量块无量纲初始动能、质量比及梁的无量纲厚度。 相似文献