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71.
AIM: To investigate the pathogenesis of chronic obstructive disease (COPD) in mice by using nasal drip of cigarette dust particles (DSP) induced pulmonary function damage model.METHODS: BALB/c mice were randomly divided into control group, LPS 100 mg/L group, DSP 0.75 mL/L group, DSP 1.5 mL/L group and DSP 3 mL/L group for 30 days. The method of nasal drip was used for 30 days to establish the COPD model. Rrs, Ers, Crs, Est, Cst, P-3/8Rn, P-3/8G and P-3/8H were measured for evaluating lung function of the mice in each group by the method of FlexiVent. The effect on the increase of airway resistance induced by methacholine (Mach) was determined using main bronchial rings by Myograph method. The HE, Masson and Resorcinol fuchsin staining of mouse tracheas and lung tissues were conducted. RESULTS: Continuous nasal drip with DSP for 30 days increased Rrs, Ers, Est, P-3/8Rn and decreased Crs, Cst, P-3/8G and P-3/8H in the mice. DSP significantly shifted the dose-effect curve of tracheal contraction induced by Mach to the left, increased the sensitivity of the airway to Mach, and significantly increased the maximal contractile airway effect of Mach. Exposure to DSP caused fibrosis of airway subepithelial, deposition of collagen in the airway basement membrane under the reticular plate, induced reticular plate thickening, pulmonary bronchial lumen serious deformation, and the inflammatory cell infiltration in the lung of mice. Significantly increased alveolar wall muscle fibers and collagen fibers were also observed. CONCLUSION: The lung function and pathomorphological changes of COPD mice induced by 30 days nasal drip of cigarette dust particles were similar to those of human COPD. 相似文献
72.
Zhang Wen-yu Xu Jia-hui Zhang Chun-yu Tong Hui-li Li Shu-feng Yan Yun-qin 《东北农业大学学报(英文版)》2021,28(3):38-47
Myoblast differentiation is an essential process during skeletal muscle development. C2 C12 myoblast is a commonly used experimental model to study muscle cell differentiation in vitro. Dehydrogenase/reductase(SDR family) member 3(DHRS3) is a highly conserved member in short-chain alcohol dehydrogenase/reductase superfamily and has been shown to be involved in the metabolism of retinol. Previous experimental results showed that the expression of DHRS3 increased significantly during the differentiation of myoblasts differentiation. However, the effect of DHRS3 on mouse muscle cell differentiation was unclear. The objective of current study was to determine if DHRS3 affected muscle cell differentiation, and if DHRS3 was involved in muscle regeneration. Protein expression was determined by western blot and immunofluorescence analysis. The activation and inhibition of DHRS3 increased and decreased C2 C12 myoblast differentiation respectively, which indicated that DHRS3 could affect C2 C12 myoblast differentiation. DHRS3 expression was significantly changed during muscle regeneration, with the regeneration of muscle injury, the expression of DHRS3 tended to increase first and then decrease. It suggested that DHRS3 might be involved in muscle regeneration. In summary, this study confirmed the involvement of DHRS3 in C2 C12 myoblast differentiation and mouse skeletal muscle regeneration and provided a theoretical basis for further elucidating the molecular mechanism of muscle development. 相似文献
73.
不同水分管理旱直播水稻生长生理与节水效应 总被引:1,自引:0,他引:1
为了探讨东北黑土区水稻高效节水种植模式,于2017年在黑龙江省庆安县采用测坑微区试验,研究了旱直播对水稻光合特性、各器官生物产量、干物质累积速率、根冠比、伤流强度、产量水分利用效率(WUEy)、叶片水分利用效率(WUEl)和产量因子等的影响。试验设置了3个处理:滴灌旱直播(DH)、漫灌旱直播(MH)和常规插秧淹灌(CK),并以CK处理作为对照。结果表明:DH与MH处理的净光合速率Pn(分蘖末期除外)、蒸腾速率Tr、气孔导度Gs、以及叶、鞘、茎、穗等冠部干物质累积量、冠部干物质累积速率(分蘖中期至末期除外)、冠部最大累积速率在整个生育期均低于CK,但WUEl、根部干物质累积量(分蘖前期和中期除外)、根部干物质累积速率、根系活力(分蘖中期与拔节孕穗期除外)均高于CK。3个处理的胞间CO2浓度Ci整个生育期波动幅度不大。根部和总干物质最大累积速率及各生育期根冠比以DH最大,CK最小。DH与MH处理的千粒质量和结实率较CK下降不显著(P0.05),穗长和穗粒数下降显著(P0.05),有效穗数上升显著(P0.05)。DH较CK、MH分别节省灌溉用水63.88%和39.52%,WUEy分别提高2.66倍和1.64倍。滴灌旱直播种植不仅大幅度减少了灌溉用水量,显著提高了水稻的WUEy,而且具有较为可观的经济效益和显著的社会效益。研究结果可为东北黑土区水稻种植模式的选取提供技术支撑,对保障黑土区农业水土资源可持续利用具有重要意义。 相似文献
74.
75.
近20年来霜冻害的发生与防御研究进展 总被引:12,自引:4,他引:12
分析了近20年来霜冻害的发生趋于严重的原因,提出了相应的防御对策措施。重点概述了近年来霜冻防御技术研究的新进展。 相似文献
76.
鲥鱼在明清一些著作中被称为瘟鱼。历来关于瘟鱼的解释主要围绕鲥鱼本身来阐发,但这些观点不能很好地解释鲥鱼为何会在江西、两湖以及四川一带被称作瘟鱼,而在盛产鲥鱼的江东却没有这种指称。明人的“瘟鱼”观点源自唐人孟诜“发疳、痼”的说法,李时珍所说的蜀地瘟鱼并不是鲥鱼。一些清人认为瘟鱼并非来自鲥鱼本身。《见闻录》中记载了一个鲥鱼被虚构成瘟鱼的故事,揭示出瘟鱼是后人将瘟疫附会到鲥鱼身上的结果。显然,鲥鱼在特定地点被称为瘟鱼,是鲥鱼与地方文化结合的产物。 相似文献
77.
78.
Xu-Xiu Lu Yao-Yao Jiang Yan-Wei Wu Guang-Ying Chen Chang-Lun Shao Yu-Cheng Gu Ming Liu Mei-Yan Wei 《Marine drugs》2022,20(1)
Brefeldin A (1), a potent cytotoxic natural macrolactone, was produced by the marine fungus Penicillium sp. (HS-N-29) from the medicinal mangrove Acanthus ilicifolius. Series of its ester derivatives 2–16 were designed and semi-synthesized, and their structures were characterized by spectroscopic methods. Their cytotoxic activities were evaluated against human chronic myelogenous leukemia K562 cell line in vitro, and the preliminary structure–activity relationships revealed that the hydroxy group played an important role. Moreover, the monoester derivatives exhibited stronger cytotoxic activity than the diester derivatives. Among them, brefeldin A 7-O-2-chloro-4,5-difluorobenzoate (7) exhibited the strongest inhibitory effect on the proliferation of K562 cells with an IC50 value of 0.84 µM. Further evaluations indicated that 7 induced cell cycle arrest, stimulated cell apoptosis, inhibited phosphorylation of BCR-ABL, and thereby inactivated its downstream AKT signaling pathway. The expression of downstream signaling molecules in the AKT pathway, including mTOR and p70S6K, was also attenuated after 7-treatment in a dose-dependent manner. Furthermore, molecular modeling of 7 docked into 1 binding site of an ARF1–GDP-GEF complex represented well-tolerance. Taken together, 7 had the potential to be served as an effective antileukemia agent or lead compound for further exploration. 相似文献
79.
【研究目的】全球升温趋势之下,极端温度变幅加大和低温造成的灾害性天气频率不减反增,2008、2011和2012宜昌柑橘产区部分或大面积发生不同程度柑橘冻害。本研究旨在增强人们对于冻害发生天气情况的了解,为柑橘产区品种规划及防寒减灾提供参考资料【方法】通过对宜昌市夷陵区历次柑橘冻害发生的气象资料统计和冻后实际调研情况分析,对最近几年冻害发生过程中不同柑橘种类和品种的表现及冻后恢复情况进行比较。【结果】发现历次大冻均发生于1月5日至1月31日之间,冻害程度与低温强度及低温持续时间呈现正相关。比较了柚、杂柑、椪柑、温州蜜柑和甜橙等不同柑橘种类在冻害中的表现,结果表明,受冻程度由重到轻依次为:杂柑→柚类→橙类→椪柑→温州蜜柑,离大水体远的果园受冻严重;坡向、坡位对冻害程度有影响。冻后恢复情况与树体冻害程度和冻后恢复能力有关,甜橙和柚冻害较重,但恢复能力较强,椪柑受冻虽然较甜橙和柚为轻,但冻后恢复较慢,而温州蜜柑冻害发生轻、冻后恢复也最快。【结论】在柑橘栽培北缘地区,因地制宜选择适宜品种、合理进行规划布局对柑橘产业健康发展极为重要。 相似文献
80.
为了缓解水蜜桃果实采后冷藏保鲜对果实品质的负面影响,达到更好的保鲜效果,以江苏省张家港市的凤凰水蜜桃(Prunus persica)为实验材料,研究了不同剂量(0.5kJ/m2、1kJ/m2、1.5kJ/m2)UV-C对低温(3℃?℃)条件下水蜜桃果实冷害和品质的影响。实验结果表明:三种剂量的UV-C处理对水蜜桃均能有效减少果实的褐变,保存果实的可溶性固形物(TSS),并明显延缓了丙二醛(MDA)、多酚氧化酶(PPO酶)的上升趋势;处理之间没有明显的效果差异,但1.5 kJ/m2处理的硬度值在5-20d之间均显著大于CK组(P<0.05),表现出更好的抗软化能力;另外,UV-C处理易使果实相对电导率加速升高,该趋势随照射剂量的增大而增强。 相似文献