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991.
Song plays a fundamental role in intraspecific communication in songbirds. The temporal and structural components of songs can vary in different habitats. These include urban habitats where anthropogenic sounds and alteration of habitat structure can significantly affect songbird vocal behavior. Urban–rural variations in song complexity, song length and syllable rate are not fully understood. In this study, using the oriental magpie‐robin (Copsychus saularis) as a model, we investigated urban–rural variation in song complexity, song length, syllable rate, syllable length and inter‐syllable interval. Comparing urban and rural songs from 7 countries across its natural Asiatic range (Bangladesh, India, Malaysia, Nepal, Singapore, Sri Lanka and Thailand), we found no significant differences in oriental magpie‐robin song complexity. However, we found significant differences in temporal song variables between urban and rural sites. Longer songs and inter‐syllable intervals in addition to slower syllable rates within urban sites contributed the most to this variance. This indicates that the urban environment may have driven production of longer and slower songs to maximize efficient transmission of important song information in urban habitats. 相似文献
992.
AIM: To investigate the expression of microRNA-193b(miR-193b) in the cervical tissues, and further to explore the effect of silencing miR-193b on diamminedichloroplatinum(DDP)-treated HeLa cell viability. METHODS: The expression levels of miR-193b in different cervical tissues were examined by qPCR. After transfection of miR-193b-inhibitor, the cell migration was determined by Transwell assay, the sensitivity of HeLa cells to DDP was measured by MTT assay, the protein levels of phosphate and tension homology deleted on chromsome ten(PTEN), protein kinase B(Akt), p-Akt and p-glycoprotein(P-gp) were determined by Western blot. RESULTS: The mRNA level of miR-193b was significantly increased in the cervical cancer tissues compared with normal cervical tissues(P<0.05). Knockdown of miR-193b obviously inhibited migration and enhanced sensitivity to DDP of HeLa cells(P<0.05). Additionally, after transfection of miR-193b-inhibitor, the expression of PTEN was increased, whereas the protein levels of p-Akt and P-gp were decreased(P<0.05). CONCLUSION: miR-193b is highly expressed in the cervical cancer tissues. Inhibition of miR-193b augments the sensitivity to DDP of HeLa cells, at least in part, through PTEN-PI3K/Akt signaling pathway. 相似文献
993.
SU Cheng-cheng XIANG Guo-an MA Yong-qiang ZHOU Xin PENG Shou-chun WEI Lu-qing JI Wen-jie 《园艺学报》2016,32(5):792-797
AIM: To investigate the effect of apyrase on the experimental silicosis. METHODS: C57BL/6 male mice were randomly divided into control group, silica treatment group, silica+apyrase group and silica+NS group. A mouse model of lung fibrosis was induced by crystalline silica particles (50 mg/kg, via oropharyngeal instillation), and were sacrificed at 3 h, 7 d, 14 d and 28 d. Apyrase was delivered by oropharyngeal aspiration at the same time and 4 h after silica challenge. The lung indexes were calculated and the concentration of ATP was detected by bioluminescent assay. The mRNA expression levels of collagen type Ⅰ(Col Ⅰ), collagen type Ⅲ (Col Ⅲ) and transforming growth factor β1 (TGF-β1) were examined by real-time PCR. The protein levels of TGF-β1 in bronchoalveolar lavage fluid were measured by ELISA. RESULTS: The elevated lung index and collagen levels showed that silicosis model was established successfully. Compared with silica group, apyrase treatment significantly alleviated silica-induced inflammation, reduced inflammation score on day 7, and decreased the lung index, collagen volume fraction and the mRNA expression of Col Ⅰand Col Ⅲ on day 28. Treatment with apyrase effectively down-regulated the mRNA levels of TGF-β1 in the lung tissues and TGF-β1 protein levels in bronchoalveolar lavage fluid on day 7.CONCLUSION: Apyrase attenuates the pulmonary inflammation and fibrosis of silicosis, which may be related with down-regulation of ATP and TGF-β1 in the lung tissues. 相似文献
994.
SU Cheng-cheng ZHANG Yi-dan XIANG Guo-an MA Yong-qiang ZHOU Xin PENG Shou-chun WEI Lu-qing JI Wen-jie 《园艺学报》2016,32(6):1112-1117
AIM: To investigate the influence of spirolactone (SPI) on mouse pulmonary macrophage subtype switching induced by silicon dioxide (SiO2). METHODS: C57BL/6 mice were divided into normal saline (NS) group, SiO2 group, SiO2+SPI group and SiO2+NS group. A mouse model of silicosis was developed with crystalline SiO2 particles (40 mg/kg, via oropharyngeal instillation). SPI (20 mg/kg) or (NS) was delivered daily by oral gavage after SiO2 administration. The mice were sacrificed on days 3, 14 and 28. Alveolar washing, total cell counting, differential cell counting and flow cytometry analysis were performed. The right lower lobe of lavaged lungs was collected to prepare single-cell suspension for flow cytometry analysis. RESULTS: Compared with SiO2 group, SPI treatment significantly alleviated SiO2-induced inflammatory cell accumulation in brochoalveolar lavage fluid on day 3 and 14. Compared with NS group, the M1 alveolar macrophages and M1 pulmonary interstitial macrophages in SiO2 group switched to M2 subtype dramatically, while SPI treatment reversed the switching effectively.CONCLUSION: SPI treatment alleviates SiO2-induced inflammatory cell accumulation, which may be related to reversing macrophage subtype switching. 相似文献
995.
澳洲野生棉种的子叶棉酚动态及与色素腺体形态的关系 总被引:2,自引:0,他引:2
对斯特提棉、南岱华棉、澳洲棉、纳尔逊氏棉和比克氏棉五个澳洲野生棉种在种子萌发过程中的子叶棉酚含量进行了测定和分析。结果表明,五个澳洲野生棉种子叶中的棉酚积累过程与无色素腺体陆地棉品种基本相似,其休眠种子和萌发24h以内的子叶均检测不到棉酚,为典型的低酚棉类型。当种子萌发48h以后,其子叶开始出现棉酚,但含量极低;在子叶开始出现棉酚1~2d后,棉酚含量开始迅速增加,到种子萌发第9d达到最大值。此外,讨论了澳洲野生棉种的子叶色素腺体延缓形成的组织结构与棉酚积累的关系,以及该性状的遗传调控机理等。 相似文献
996.
PENG Xuya JI Fangying XIAO Bo LIU Guotao 《保鲜与加工》1999,(6):66-69
On the basis of analyzing the landfill gas production and its affecting factors, the methods for accelerating the production of landfill gas and settlement of landfill site are put forward in this paper. 相似文献
997.
998.
施用碱稳定污泥污水土壤经γ-辐照后土壤溶液中Cu和Zn 总被引:1,自引:0,他引:1
Soil samples collected from several acid soils in Guangdong, Fujian, Zhejiang and Anhui provinces of the southern China were employed to characterize the chemical species of aluminumions in the soils. The proportion of monomeric inorganic Al to total Al in soil solution was in the range of 19% to 70%, that of monomeric organic Al (Al-OM) to total Al ranged from 7.7% to 69%, and that of the acid-soluble Al to total Al was generally smaller and was lower than 20% in most of the acid soils studied. The Al-OM concentration in soil solution was positively correlated with the content of dissolved organic carbon (DOC) and also affected by the concentration of Al3+. The complexes of aluminum with fluoride (Al-F) were the predominant forms of inorganic Al, and the proportion of Al-F complexes to total inorganic Al increased with pH. Under strongly acid condition, Al3+ was also a major form of inorganic Al, and the proportion of Al3+ to total inorganic Al decreased with increasing pH. The proportions of Al-OH and Al-SO4 complexes to total inorganic Al were small and were not larger than 10% in the most acid soils. The concentration of inorganic Al in solution depended largely on pH and the concentration of total F in soil solution. The concentrat ions of Al-OM, Al3+, Al-F and Al-OH complexes in topsoil were higher than those in subsoil and decreased with the increase in soil depth. The chemical species of aluminumions were influenced by pH. The concentrations of Al-OM, Al3+, Al-F complexes and Al-OH complexes decreased with the increase in pH. 相似文献
999.
光抑制条件下不同水稻品种叶片的PSⅡ光化学效率和CO_2交换特性的差异 总被引:8,自引:2,他引:6
比较了光抑制条件下两个水稻品种叶片的PSⅡ电子传递活性、D1蛋白量、叶绿素荧光Fv/Fm、净光合(PN)和光呼吸(PR)速率、碳酸酐酶(CA)、PEPC和RuBP羧化/加氧酶活性的变化,并对RuBP羧化酶进行了动力学分析。经光抑制处理后,耐光抑制品种02428较对光抑制敏感品种3037中D1蛋白净降解少、PSⅡ活性和PSⅡ原初光化学效率高,光抑制较轻;RuBP羧化/加氧酶活性和RuBP羧化酶的Km(CO2)和Vmax(CO2)值没有变化,且在品种间无差异。CA和PEPC活性出现诱导增高,尤以品种02428中活性诱导的幅度更高。CO2交换特点发生了显著变化,在PN降低的同时,Pa/PN比值明显增加,品种3037的PR/PN比值比02428的更大。在水稻耐光抑制特性上,D1蛋白、CA和PEPC可能分别对PSⅡ光化学效率和CO2交换起着重要的调节作用。 相似文献
1000.