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991.
Wenbo Luo Weiqi He Suyong Yang Wenfeng Feng Taolin Chen Lili Wang Tian Gan Yue-jia Luo 《Biological psychology》2013
Using measurements of event-related potentials (ERPs) during a facial recognition task, we aimed to investigate the facial inversion effect and the role of time-based attention in processing upright and inverted faces. We presented upright and inverted faces at the T2 (target 2) position using a rapid serial visual presentation paradigm. Our results indicate that the N170 component shows the usual face inversion effect (FIE), in which inverted faces elicit larger N170 amplitudes and a longer elicit N170 latency. We also found that upright faces elicit larger P1 amplitudes than inverted faces over the left hemisphere. This study indicates that the N170 and P3, but not the P1, components are modulated by time-based attention. In addition, we found that the N170 amplitude was modulated by an attentional blink (AB) based on behavioral data. These results suggest that the disruption of facial configuration processing caused by inverted faces is relatively independent of attentional resources. 相似文献
992.
Bo Liu Jiwen Luo Junxiang Lu Hongbing Deng 《Journal of biomaterials science. Polymer edition》2013,24(5):589-605
Drug-delivery systems, using natural drug carriers, have become increasingly important because of their nontoxicity and biodegradability. In this study, firstly, quaternized carboxymethyl chitosan (QCMC) was intercalated into the interlayer of organic montmorillonite (OMMT) to obtain the QCMC/OMMT nanocomposites, their structure, morphology, and thermal stability were investigated. Next, crosslinked alginate/QCMC/OMMT (AQCOM) microsphere was obtained by crosslinking with CaCl2, and the drug-controlled release behavior was evaluated with bovine serum albumin (BSA) as model drug. The results suggested that, carboxyl groups in alginate and QCMC crosslinked with Ca2+, quaternary ammonium groups in QCMC or OMMT electrostatically interacted with carboxyl groups in alginate, and there was stable three-dimensional network in AQCOM microsphere. The swelling ratio of AQCOM microspheres decreased with the increase of OMMT content, the lowest one was only about 45% compared to the microsphere without OMMT of 197%. Besides, the in vitro release results for BSA indicated that the AQCOM microsphere displayed more excellent encapsulation and controlled release capacities than the microsphere without OMMT. The in vitro active cutaneous anaphylaxis test was carried out on Guinea pigs, which revealed that AQCOM microsphere did not cause anaphylaxis. Therefore, QCMC/OMMT nanocomposites from natural materials are considerably suitable to apply as drug-controlled release carriers. 相似文献
993.
Nianping Jiang Li Zhong Chunlai Zhang Xiangguo Luo Peng Zhong Xiaoguang Li 《Breast care (Basel, Switzerland)》2021,16(3):283
BackgroundThere is substantial overlap in MRI findings between phyllodes tumors (PTs) and fibroadenomas (FAs). Our study was performed to investigate the value of conventional MRI texture analysis in the differential diagnosis of PTs and FAs.MethodsPreoperative MRI data − including axial T1WI, T2WI<sub>FS</sub> (T2WI with fat suppression), dynamic contrast-enhanced (DCE)-T1WI<sub>2min</sub> and DCE-T1WI<sub>7min</sub> (T1WI post-strengthened for 2 and 7 min, respectively, on DCE-MRI) − of 45 patients with PTs and 67 patients with FAs were retrospectively analyzed. MaZda 4.7 software was used to manually draw the maximum ROIs at the same lesion level of the above MRI images. The optimized feature selection methods included Fisher''s coefficient, probability of classification error and average correction coefficient (POE + ACC), and mutual information (MI) as well as a combination of the above 3 methods (F + POE + ACC + MI [FPM]), respectively. The misclassification rates of PTs and FAs were compared between texture analysis and subjective diagnosis by radiologists.ResultsThe DCE-T1WI<sub>7min</sub> images had the lowest misclassification rate of 10.71% (12/112). The misclassification rate for the radiologists'' analysis (31.25%, 35/112) was higher than that of all the texture analysis, and there was a statistically significant difference between the radiologists'' misclassification rates and those from the FPM method in terms of the T2WI<sub>FS</sub> and DCE-T1WI<sub>2min</sub> images (all p < 0.05), and for the DCE-T1WI<sub>7min</sub> images by using the Fisher and FPM methods (all p < 0.05).ConclusionTexture analysis of conventional MRI can be used as an assistant tool in providing a certain objective basis for differentiating PTs from FAs. 相似文献
994.
创伤性凝血病和过度炎症导致的多器官功能障碍综合征是严重创伤危及患者生命的重要因素.氨甲环酸(TXA)是一种人工合成抗纤溶药物,兼具抗纤溶、抗炎、免疫调节及减轻血管内皮损伤等多重作用.TXA给药方式灵活,除静脉途径外,还可以口服、创伤局部使用或肌肉注射.多部国内外专家共识或指南均建议创伤后3h内应用TXA以降低创伤出血所致的病死率,推荐用法为:10min内给予1g负荷量静脉输注,随后8h给予1g维持量.时间窗内使用TXA是创伤救治策略的重要一环. 相似文献
995.
Yi-Min Sun MD PhD Hui-Ling Yu MD Xin-Yue Zhou MD Wei-Xi Xiong MD Su-Shan Luo MD PhD Chen Chen MD PhD Feng-Tao Liu MD PhD Jue Zhao MD Yi-Lin Tang MD PhD Xiao-Niu Liang PhD Yu-Jie Yang PhD Bo Shen MD PhD Yan Shen MD PhD Wen-Bo Yu MD PhD Zheng-Tong Ding MD PhD Yu An PhD Jian-Jun Wu MD PhD Jian Wang MD PhD 《Movement disorders》2021,36(2):442-448
996.
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998.
Shuai Chen Gengbing Lin Lang Lei Xiaoqing You Chunfang Wu Wenjing Xu Min Huang Lan Luo Zhijun Wang Yanfen Li Xin Zhao Fuhua Yan 《Inflammation》2013,36(4):968-976
The objective of this study was to investigate the effect of hyperlipidemia (HLP) on innate immune responses to lipopolysaccharide (LPS). Male New Zealand white rabbits were fed a normal diet (ND) or a high-fat diet (HFD) for 8 weeks. In vivo, the rabbits were injected intravenously with LPS for 24 h. In vitro, peripheral mononuclear cells were collected and stimulated (or unstimulated) with LPS for 24 h. Assay results were analyzed with one-way ANOVA or an equivalent non-parametric test. A P value of 0.05 was considered statistically significant. Despite having no influence in body weight, the HFD intake significantly increased serum lipids, C-reactive protein (CRP), nuclear factor (NF)-κB subunit p65, Toll-like receptor (TLR)-4, SR-A and FAS. Although we found increased circulating tumor necrosis factor (TNF)-α, interleukin (IL)-6, CRP, IL-1β, and IL-10 in the ND-fed rabbits, no significant difference was found in the LPS-stimulated production of TNF-α, IL-6, and CRP in the HFD-fed rabbits. The macrophages harvested from the HFD-fed rabbits developed a blunted inflammatory response, with lower mRNA expression of TNF-α, IL-6, CRP, TLR-4, SR-A, FAS, and Bcl-2 than that expressed by the ND group. In the HFD-fed animals, LPS incubation decreased NF-κB subunit p65 expression, whereas the cytoplasmic phosphorylation of the inhibitor of NF-κB protein was enhanced. These data indicate that HLP displayed a form of innate immune paralysis, including reduced pro- and anti-inflammatory cytokine release to external stimulus, which was related to the altered TLR-NF-κB signaling pathway and altered pro- and anti-apoptotic processes in macrophages. 相似文献
999.
Zhuan-Ling Lu Wen Wang Wei-Li Yin Hai-Bo Tang Yan Pan Xiang Liang Qi Liu Yi Xiong Nobuyuki Minamoto Ting Rong Luo 《Virus genes》2013,46(2):293-301
Although rabies virus is widely distributed in the world, and has been the subject of extensive investigations with the objective of its ultimate prevention, control, and management, there is much less knowledge of the characteristics, distribution, and infectivity of other lyssaviruses. Since bats are known animal vectors for all but one of the known lyssavirus genotypes, we have performed an extensive survey of bats in the Guangxi Province to provide information on lyssavirus distribution in southern China. The lyssavirus nucleoprotein gene was detected in brains of 2.86 % of 2,969 bats. Nucleotide sequence homologies among isolates were 86.9–99.6 %, but only 70.0–85.0 % for lyssaviruses in GenBank. These infected bats were detected from a wide area, essentially forming a band running from the south-west to the north-east of Guangxi, and it appears that infection by new lyssaviruses is widespread in this region. 相似文献
1000.
Zu-Hua Yu Man Teng Jun Luo Xin-Wei Wang Ke Ding Le-Le Yu Jing-Wei Su Jia-Qi Chi Pu Zhao Bo Hu Gai-Ping Zhang Ju-Xiong Liu 《Virus genes》2013,47(2):282-291
Marek’s disease is a highly contagious, oncogenic, and immunosuppressive avian viral disease. Surveillance of newly registered Marek’s disease virus (MDV) isolates is meaningful for revealing the potential factors involved in increased virulence. Presently, we have focused on the molecular characteristics of all available MDVs from China, including 17 new Henan isolates. Based on Meq, gE, and gI genes, we found that most Chinese isolates contain conserved amino acid point mutations in Meq, such as E77, A115, A139, R176, and A217, compared to USA virulent MDVs. However, the 59-aa or 60-aa insertions are only found in a few mild MDVs rather than virulent MDVs in China. Further phylogenetic analysis has demonstrated that a different genotype of MDV has been prevalent in China, and for virulent MDVs, their recent evolution has possibly been geographically restricted. Our study has provided more detailed information regarding the field MDVs circulating in China. 相似文献