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951.
Differences in how writing systems represent language raise important questions about whether there could be a universal functional architecture for reading across languages. In order to study potential language differences in the neural networks that support reading skill, we collected fMRI data from readers of alphabetic (English) and morpho-syllabic (Chinese) writing systems during two reading tasks. In one, participants read short stories under conditions that approximate natural reading, and in the other, participants decided whether individual stimuli were real words or not. Prior work comparing these two writing systems has overwhelmingly used meta-linguistic tasks, generally supporting the conclusion that the reading system is organized differently for skilled readers of Chinese and English. We observed that language differences in the reading network were greatly dependent on task. In lexical decision, a pattern consistent with prior research was observed in which the Middle Frontal Gyrus (MFG) and right Fusiform Gyrus (rFFG) were more active for Chinese than for English, whereas the posterior temporal sulcus was more active for English than for Chinese. We found a very different pattern of language effects in a naturalistic reading paradigm, during which significant differences were only observed in visual regions not typically considered specific to the reading network, and the middle temporal gyrus, which is thought to be important for direct mapping of orthography to semantics. Indeed, in areas that are often discussed as supporting distinct cognitive or linguistic functions between the two languages, we observed interaction. Specifically, language differences were most pronounced in MFG and rFFG during the lexical decision task, whereas no language differences were observed in these areas during silent reading of text for comprehension. 相似文献
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Mei Li Zhong Wei Jianing Wang Alexandre Jousset Ville‐Petri Friman Yangchun Xu Qirong Shen Thomas Pommier 《Ecology letters》2019,22(1):149-158
While several studies have established a positive correlation between community diversity and invasion resistance, it is less clear how species interactions within resident communities shape this process. Here, we experimentally tested how antagonistic and facilitative pairwise interactions within resident model microbial communities predict invasion by the plant–pathogenic bacterium Ralstonia solanacearum. We found that facilitative resident community interactions promoted and antagonistic interactions suppressed invasions both in the lab and in the tomato plant rhizosphere. Crucially, pairwise interactions reliably explained observed invasion outcomes also in multispecies communities, and mechanistically, this was linked to direct inhibition of the invader by antagonistic communities (antibiosis), and to a lesser degree by resource competition between members of the resident community and the invader. Together, our findings suggest that the type and strength of pairwise interactions can reliably predict the outcome of invasions in more complex multispecies communities. 相似文献
954.
睫状神经营养因子对大鼠去神经骨骼肌的营养作用 总被引:6,自引:0,他引:6
目的:了解睫状神经营养因子(CNTF)对去神经引起的肌肉萎缩的治疗作用。方法:离断SD大鼠一侧坐骨神经,连续给予CNTF20d,观察肌肉湿重、蛋白含量、肌纤维横截面积、收缩性能和残肢程度。结果:①给予0.2mg/kg的CNTF,可使损务侧肌纤维横截面积增加35%,肌肉湿重增加38%,胫前肌总蛋白含量增加24%,腓长肌强直收缩强度提高40%,显著改善肢残程度;②0.2mg/kg的CNTF作用明显强于0.05mg/kg的CNTF;③此目鱼肌(慢肌)比伸趾长肌(快肌)对CNTF更敏感。结论:CNTF能显著改善成年大鼠坐骨神经离断后骨骼肌的萎缩和功能丧失,该效应的强弱与用药剂量和肌肉类型有关。 相似文献
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Hong Huo Yikun Gao Tianyi Wang Haitao Jiang Siling Wang Tongying Jiang 《AAPS PharmSciTech》2012,13(4):1367-1376
To prepare stable polyion complex (PIC) micelles, polyasparthydrazide (PAHy) modified with glycidyltrimethylammonium groups and methoxy poly(ethylene glycol) (mPEG) (mPEG-g-PAHy-GTA) was synthesized. The cytotoxicity of the polymer was evaluated by the methyl tetrazolium assay. The polymer entrapped the diammonium glycyrrhizinate (DG) and formed polyion complexes. The effect of pH value, grafting degree of mPEG, copolymer and drug concentration on the micelle formation was investigated by means of measuring entrapment efficiency and micelle size. In vitro DG release from the PIC micelles was detected by dialysis in various media of different ionic strengths. To examine the pharmacokinetic behavior of micelles in vivo, the time course of the drug in plasma was evaluated. The cytotoxicity of the polymer was very low. The results showed that entrapment efficiency can reach about 93%, and the mean particle size was almost 50 nm. The drug release rate decreased with a decrease in ionic strength of the release medium or an increase in the PEG grafting degree. Compared with DG solution, the AUC of DG micelles had a twofold increase. The smaller clearance and longer mean residence time of the DG micelles group compared with DG solution group showed that the DG loaded in PIC micelles can reduce drug elimination and prolong the drug residence time in the blood circulation. The results indicated that PIC micelles composed of mPEG-g-PAHy-GTA would be prospective as a drug carrier to the drugs which can be ionized in solution.KEY WORDS: diammonium glycyrrhizinate, drug delivery systems, poly(ethylene glycol)–glycidyltrimethylammonium chloride-grafted polyasparthydrazide, polyion complex micelles 相似文献
959.
Overexpression of Jatropha curcas Defensin (JcDef) Enhances Sheath Blight Disease Resistance in Tobacco 下载免费PDF全文
Qingwei Wang Shuhua Zhu Yao Liu Rui Li Shancai Tan Shenghua Wang Lin Tang Fang Chen 《Journal of Phytopathology》2017,165(1):15-21
Plant defensins are small, basic, cysteine‐rich peptides, belonging to the antimicrobial peptide superfamily, commonly found in the plant kingdom. In this study, we cloned and characterized a plant defensin gene from Jatropha curcas (JcDef). JcDef carried conserved receptor binding sites and a cysteine motif, and it was phylogenetically grouped together with defensin Ec‐AMP‐D2‐like in Elaeis guineensis. JcDef is localized to cytoplasm and highly expressed in young tissues with fast metabolism such as cotyledons and stem apexes. Transgenic expression of JcDef in tobacco showed enhanced resistance against sheath blight disease caused by R. solani, indicating the antibacterial function. 相似文献
960.
氯喹对戊四氮致痫大鼠皮质和海马白细胞介素1β及肿瘤坏死因子α表达的影响 总被引:2,自引:0,他引:2
目的观察氯喹对戊四氮致痫大鼠皮质和海马白细胞介素1β(IL-1β)及肿瘤坏死因子α(TNF-α)表达的影响,探讨其在癫痫发生发展过程中的作用.方法 48只健康雄性SD大鼠随机分为对照组(12只)、戊四氮(PTZ)致痫组(18只,60mg/kg,i.p.)和氯喹干预组(18只,氯喹0.61mg/kg,i.c.v.,2h后注射PTZ).每组确定6个时间点:1h、2h、4h、8h、12h和24h.观察大鼠行为表现,记录脑电改变,用免疫组化检测皮质和海马IL-1β和TNF-α表达的变化.结果对照组无痫样发作和痫样放电,戊四氮致痫组痫样发作重(Ⅲ-Ⅴ级),氯喹干预组轻(Ⅰ-Ⅲ级)(P<0.05);脑电记录显示戊四氮致痫组呈频发高幅的痫样波,氯喹干预组痫样波幅低且缓;LI-1β和TNF-α在戊四氮致痫组皮质和海马表达强,与对照组比较差异有显著性(P<0.05),氯喹干预组与对照组比较差异无显著性(P>0.05).结论氯喹可能通过对IL-1β和TNF-α表达的抑制减轻戊四氮致痫大鼠的痫样放电和痫样发作程度.这些结果提示,氯喹在防治癫痫方面可能是理想的抗痫剂. 相似文献