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61.
Peptide-containing hydrogels have become a research hotspot due to their unique secondary structure and biocompatibility. Herein, we used amino-terminated F127 as a macroinitiator to initiate the ring-opening polymerization of l-lysine(z)-NCA, and the obtained oligo(lysine)-modified F127 (FL) had degrees of polymerization of lysine of 2, 5, and 8. The results showed that the FL hydrogels had reversible temperature-dependent sol–gel transitions, and the introduction of lysine increased the critical gel temperature. In the dilute solution of FL, the micelle size increased and aggregated as the pH increased; the micelle grew into a rod-like shape under alkaline conditions. Scanning electron micrographs showed that the interior of the FL hydrogel had a more complete porous structure. The FL-2 hydrogel loaded with 5-fluorouracil exhibited an approximately linear release trend within 12 h and has good biocompatibility. Therefore, FL hydrogels have potential applications in the field of biomedicine.Oligo(lysine)-F127 hydrogels have a temperature-responsive sol–gel transition and pH-responsive micelle morphology. 相似文献
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The influence of basolateral amygdala (BLA) on memory is known to depend critically on adrenergic neurotransmission. However, the roles of noradrenergic receptors on memory retrieval have been elusive and controversial. Here, we investigated the effect of beta(1)-adrenoceptor (beta(1)-AR) on auditory fear memory in the rat BLA. We attenuated the expression of beta(1)-AR by RNA interference, a popular means to specific suppress gene expression. Bilaterally microinjection of beta(1)-AR short interfering RNA (siRNA) could reach a satisfying transfection in the BLA: beta(1)-AR protein expression was reduced transiently by siRNA in vivo at day 3. The behavioral tests indicated that memory retrieval was impaired as beta(1)-AR protein expression was prevented, and the memory was restored when the beta(1)-AR protein got back to normal level. The results suggested that beta(1)-AR might be critical for the retrieval of auditory fear memory. 相似文献
65.
Zhao Xiaoxin Yao Jingjing Lv Yiding Zhang Xinyue Han Chongyang Chen Lijun Ren Fangfang Zhou Qun Jin Zhuma Li Yuan Du Yasong Sui Yuxiu 《Brain imaging and behavior》2022,16(5):2072-2085
Brain Imaging and Behavior - Impaired capability for understanding and interpreting the expressions on other people's faces manifests itself as a core feature of schizophrenia, contributing to... 相似文献
66.
Shao Xiexiang Sui Wenyuan Deng Yaolong Yang Jingfan Chen Jian Yang Junlin 《European spine journal》2022,31(4):996-1005
European Spine Journal - To introduce and evaluate our lowest instrumented vertebra (LIV) selection criteria for Lenke type 5/6 adolescent idiopathic scoliosis (AIS) patients with de-rotation... 相似文献
67.
目的探讨术中x-线定位在经神经内镜下甲介型蝶窦垂体瘤手术的应用。方法回顾性分析6例甲介型蝶窦垂体瘤病人的临床资料,均采用神经内镜下垂体瘤切除结合术中X-线定位方法。结果术中X-线定位准确4例;2例发生纵向偏差,均纠正。肿瘤全切除5例,次全切除1例。术后激素水平正常,视力视野改善。出现暂时性尿崩1例,治疗后痊愈。无脑脊液鼻漏、垂体功能低下、蝶窦炎发生,无死亡病例。6例病人随访3年,均无复发。结论神经内镜技术结合术中X-线定位是一种治疗甲介型蝶窦垂体瘤的安全、有效方法。 相似文献
68.
Internet addiction (IA) is an emerging social and mental health issue among youths. Analysis of risk factors, as well as their interactions, is crucial for understanding the development of IA. This study investigated the relationship between recent stressful life events, personality traits, perceived family functioning and IA in 892 college students. Subjects were classified into categories (non‐addicted, mild IA or severe IA) using the Chen Internet Addiction Scale. Stressful life events, personality traits and family functioning were assessed using the Adolescent Self‐Rating Life Events Checklist, the Eysenck Personality Questionnaire, and the Family Adaptability and Cohesion Scale, respectively. The results indicated that compared with non‐addicted subjects, subjects with severe IA (9.98%) had lower family functioning, lower extraversion, higher neuroticism and psychoticism, and more stressful life events, and subjects with mild IA (11.21%) had higher neuroticism and more health and adaptation problems. Neuroticism and health and adaptation problems were potential predictors of IA. An interaction effect between psychoticism and total life stress on IA was also found. These findings highlight the role of personality traits and life stress and their interactions in college students' IA. Further research should explore the mechanisms underlying the interaction effect of psychoticism with life stress on IA. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
69.
With low melting point, extremely low vapor pressure and non-flammability, ionic liquids have been attracting much attention from academic and industrial fields. Great efforts have been made to facilitate their applications in catalytic processes, extraction, desulfurization, gas separation, hydrogenation, electronic manufacturing, etc. To reduce the cost and environmental effects, different technologies have been proposed to recover the ionic liquids from different solutions after their application. This review is mainly focused on the recent advances of the recovery and purification of ionic liquids from solutions. Several methods for recovery of ionic liquids including distillation, extraction, adsorption, membrane separation, aqueous two-phase extraction, crystallization and external force field separation, are introduced and discussed systematically. Some industrial applications of ionic liquid recovery and purification methods are selected for discussion. Additionally, considerations on the combined design of different methods and process optimization have also been touched on to provide potential insights for future development of ionic liquid recovery and purification.Recovery and purification of ionic liquids from solutions. 相似文献
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