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不同性质气体煤体受载渗透率演化规律研究
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作者 曹塘根 张小东 +5 位作者 李泽文 雷军 罗勇 费浩 王登科 白云 《黑龙江科学》 2025年第6期5-11,共7页
为研究不同性质气体压力和气体吸附时间下受载含瓦斯煤渗透率变化规律,利用受载煤岩工业CT伺服加载系统,开展不同性质气体(He/CO_(2))压力与不同吸附性气体(CO_(2))吸附时间煤体渗透率测定实验,建立了受载含瓦斯煤渗透率模型。结果表明... 为研究不同性质气体压力和气体吸附时间下受载含瓦斯煤渗透率变化规律,利用受载煤岩工业CT伺服加载系统,开展不同性质气体(He/CO_(2))压力与不同吸附性气体(CO_(2))吸附时间煤体渗透率测定实验,建立了受载含瓦斯煤渗透率模型。结果表明,在围压和轴压固定的条件下,随着He孔隙压力的增大,其渗透率随之减小,而随着CO_(2)孔隙压力的增大,煤样的渗透率结果呈现非线性变化,为V字型变化。在围压轴压及孔隙压力都固定的条件下,随着CO_(2)时间的增加,其渗透率结果呈现出先减小后增大的趋势。在全应力-应变的条件下,煤样的渗透率结果随着轴压的增大呈现出先减小后增大的U字型趋势。利用实验结果对模型进行验证,发现模型与实验结果高度吻合。 展开更多
关键词 含瓦斯煤 渗透率演化 气体性质 吸附时间 工业CT
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Activation of adult endogenous neurogenesis by a hyaluronic acid collagen gel containing basic fibroblast growth factor promotes remodeling and functional recovery of the injured cerebral cortex
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作者 Yan Li Peng hao +6 位作者 Hongmei Duan fei hao Wen Zhao Yudan Gao Zhaoyang Yang Kwok-Fai So Xiaoguang Li 《Neural Regeneration Research》 SCIE CAS 2025年第10期2923-2937,共15页
The presence of endogenous neural stem/progenitor cells in the adult mammalian brain suggests that the central nervous system can be repaired and regenerated after injury.However,whether it is possible to stimulate ne... The presence of endogenous neural stem/progenitor cells in the adult mammalian brain suggests that the central nervous system can be repaired and regenerated after injury.However,whether it is possible to stimulate neurogenesis and reconstruct cortical layers II to VI in non-neurogenic regions,such as the cortex,remains unknown.In this study,we implanted a hyaluronic acid collagen gel loaded with basic fibroblast growth factor into the motor cortex immediately following traumatic injury.Our findings reveal that this gel effectively stimulated the proliferation and migration of endogenous neural stem/progenitor cells,as well as their differentiation into mature and functionally integrated neurons.Importantly,these new neurons reconstructed the architecture of cortical layers II to VI,integrated into the existing neural circuitry,and ultimately led to improved brain function.These findings offer novel insight into potential clinical treatments for traumatic cerebral cortex injuries. 展开更多
关键词 adult endogenous neurogenesis basic fibroblast growth factor-hyaluronic acid collagen gel cortical remodeling functional recovery migration motor cortex injury neural circuits neural stem cells newborn neurons proliferation
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PIAS3缺失促进雌性ApoE基因敲除小鼠动脉粥样硬化发展
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作者 李超超 黄会紫 +3 位作者 张璟怡 费浩 杨立伟 王蓉 《中国动脉硬化杂志》 2025年第8期665-672,共8页
[目的]探讨活化STAT3蛋白抑制因子(PIAS3)缺失是否促进雌性ApoE基因敲除小鼠动脉粥样硬化(As)的发生发展。[方法]繁育ApoE^(-/-)背景的PIAS3基因敲除小鼠(PIAS3^(-/-)/ApoE^(-/-)),并饲喂高脂高胆固醇饮食12周诱导As。以同窝PIAS3+/+/Ap... [目的]探讨活化STAT3蛋白抑制因子(PIAS3)缺失是否促进雌性ApoE基因敲除小鼠动脉粥样硬化(As)的发生发展。[方法]繁育ApoE^(-/-)背景的PIAS3基因敲除小鼠(PIAS3^(-/-)/ApoE^(-/-)),并饲喂高脂高胆固醇饮食12周诱导As。以同窝PIAS3+/+/ApoE^(-/-)小鼠作为对照。每周测量小鼠体重,每4周检测血脂水平(包括总胆固醇、甘油三酯、高密度脂蛋白胆固醇和非高密度脂蛋白胆固醇)。对小鼠主动脉树、主动脉根部冰冻切片进行油红O染色、HE染色、免疫组织化学染色和免疫荧光染色,以评估As斑块的面积、细胞成分及其稳定性。此外,通过免疫荧光染色分析斑块内雌激素受体α(ERα)的表达及其与血管平滑肌细胞(VSMC)共定位情况。[结果]与PIAS3+/+/ApoE^(-/-)小鼠相比,PIAS3^(-/-)/ApoE^(-/-)小鼠的体重、主要脏器(心脏、肝脏、脾脏、肾脏和附睾脂肪)的重量及血脂水平均无明显改变;然而,PIAS3缺失促进了雌性PIAS3^(-/-)/ApoE^(-/-)小鼠As的形成。与PIAS3+/+/ApoE^(-/-)小鼠相比,PIAS3^(-/-)/ApoE^(-/-)小鼠As斑块内脂质蓄积含量增加(P<0.05),VSMC含量减少(P<0.05),斑块稳定性降低。除此之外,PIAS3^(-/-)/ApoE^(-/-)小鼠As斑块内ERα的表达明显下调(P<0.05),且ERα与VSMC存在明显共定位。PIAS3^(-/-)/ApoE^(-/-)小鼠斑块内VSMC的减少可能导致ERα的表达降低,进而减弱雌激素抗As的作用。[结论]PIAS3缺失促进雌性ApoE^(-/-)小鼠As斑块形成,并且PIAS3可能通过调控斑块内ERα的表达来发挥作用。 展开更多
关键词 动脉粥样硬化 活化STAT3蛋白抑制因子 雌激素受体 血管平滑肌细胞
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咸阳市中医药创新型产业集群发展研究
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作者 郝斐 甘军委 +3 位作者 吴小勇 陶桂松 文华清 丁敬敏 《产业科技创新》 2025年第1期43-48,共6页
本文首先从理论上论述了产业集群的相关概念,以准确规范的分析方法综述了前人的理论成果,并采用问卷调查方式从行业结构、地区分布等角度准确把握咸阳市中医药产业集群发展状况,运用一系列科学分析方法对咸阳市中医药产业集群发展进行... 本文首先从理论上论述了产业集群的相关概念,以准确规范的分析方法综述了前人的理论成果,并采用问卷调查方式从行业结构、地区分布等角度准确把握咸阳市中医药产业集群发展状况,运用一系列科学分析方法对咸阳市中医药产业集群发展进行研究和分析,对咸阳市中医药产业集群的优势、劣势、机会、挑战等内外环境以及资源要素进行研究和分析,充分认识到咸阳市中医药产业集群发展存在的问题和不足。最后,在上述分析研究基础上,把AHP层次分析法运用到SWOT分析中,对咸阳市中医药产业集群发展过程中各种影响因素进行了科学分析并提出了相应发展战略。 展开更多
关键词 中医药 产业集群 创新 发展
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微创小切口下缝线桥术治疗肱骨大结节骨折的效果分析
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作者 徐大伟 丁晓敏 +4 位作者 周进 费毫 成冬冬 周思怡 刘巍 《南通大学学报(医学版)》 2024年第4期326-329,共4页
目的:比较经肩关节前外侧入路缝线桥技术与经三角肌胸大肌间沟入路钢板螺钉固定治疗肱骨大结节骨折的临床效果。方法:回顾性分析2019年1月—2024年1月诊治的肱骨大结节骨折40例,根据手术入路和内固定方式分为缝线桥组(n=18)和钢板组(n=2... 目的:比较经肩关节前外侧入路缝线桥技术与经三角肌胸大肌间沟入路钢板螺钉固定治疗肱骨大结节骨折的临床效果。方法:回顾性分析2019年1月—2024年1月诊治的肱骨大结节骨折40例,根据手术入路和内固定方式分为缝线桥组(n=18)和钢板组(n=22),缝线桥组予肩关节前外侧入路缝线桥技术治疗,钢板组予三角肌胸大肌间沟入路钢板螺钉固定治疗。比较两组患者切口长度、出血量、手术时间、住院时间、术后1 d疼痛视觉模拟评分(visual analogue scale,VAS评分)、肩关节功能Neer评分,并记录两组内固定的不良反应情况。结果:与钢板组相比,缝线桥组切口长度短,术中出血量、手术时间和住院时间少,术后1 d疼痛VAS评分低,术后1、3个月和末次随访肩关节功能Neer评分高,差异均有统计学意义(均P<0.05)。两组切口均为一期愈合,无神经损伤,术后半年随访X线片均提示骨折愈合良好。钢板组发生头静脉损伤3例,肩峰下撞击并发症4例。结论:运用微创小切口结合缝线桥技术治疗肱骨大结节骨折创伤小,并发症少,术后疼痛缓解和肩关节功能恢复效果佳,是一种微创和有效的治疗方法。 展开更多
关键词 肱骨大结节骨折 微创 锚钉 缝线桥
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Activation of endogenous neurogenesis and angiogenesis by basic fibroblast growth factor-chitosan gel in an adult rat model of ischemic stroke 被引量:7
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作者 Hongmei Duan Shulun Li +11 位作者 Peng hao fei hao Wen Zhao Yudan Gao Hui Qiao Yiming Gu Yang Lv Xinjie Bao Kin Chiu Kwok-Fai So Zhaoyang Yang Xiaoguang Li 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第2期409-415,共7页
Attempts have been made to use cell transplantation and biomaterials to promote cell proliferation,differentiation,migration,and survival,as well as angiogenesis,in the context of brain injury.However,whether bioactiv... Attempts have been made to use cell transplantation and biomaterials to promote cell proliferation,differentiation,migration,and survival,as well as angiogenesis,in the context of brain injury.However,whether bioactive materials can repair the damage caused by ischemic stroke by activating endogenous neurogenesis and angiogenesis is still unknown.In this study,we applied chitosan gel loaded with basic fibroblast growth factor to the stroke cavity 7 days after ischemic stroke in rats.The gel slowly released basic fibroblast growth factor,which improved the local microenvironment,activated endogenous neural stem/progenitor cells,and recruited these cells to migrate toward the penumbra and stroke cavity and subsequently differentiate into neurons,while enhancing angiogenesis in the penumbra and stroke cavity and ultimately leading to partial functional recovery.This study revealed the mechanism by which bioactive materials repair ischemic strokes,thus providing a new strategy for the clinical application of bioactive materials in the treatment of ischemic stroke. 展开更多
关键词 adult endogenous neurogenesis ANGIOGENESIS basic fibroblast growth factor-chitosan gel CHITOSAN functional recovery ischemic stroke neural stem cell newborn neuron
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Visualizing Wallerian degeneration in the corticospinal tract after sensorimotor cortex ischemia in mice 被引量:3
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作者 Jiao Mu Liufang hao +6 位作者 Zijue Wang Xuyang Fu Yusen Li fei hao Hongmei Duan Zhaoyang Yang Xiaoguang Li 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第3期636-641,共6页
Stroke can cause Wallerian degeneration in regions outside of the brain,particularly in the corticospinal tract.To investigate the fate of major glial cells and axons within affected areas of the corticospinal tract f... Stroke can cause Wallerian degeneration in regions outside of the brain,particularly in the corticospinal tract.To investigate the fate of major glial cells and axons within affected areas of the corticospinal tract following stroke,we induced photochemical infarction of the sensorimotor cortex leading to Wallerian degeneration along the full extent of the corticospinal tract.We first used a routine,sensitive marker of axonal injury,amyloid precursor protein,to examine Wallerian degeneration of the corticospinal tract.An antibody to amyloid precursor protein mapped exclusively to proximal axonal segments within the ischemic cortex,with no positive signal in distal parts of the corticospinal tract,at all time points.To improve visualization of Wallerian degeneration,we next utilized an orthograde virus that expresses green fluorescent protein to label the corticospinal tract and then quantitatively evaluated green fluorescent protein-expressing axons.Using this approach,we found that axonal degeneration began on day 3 post-stroke and was almost complete by 7 days after stroke.In addition,microglia mobilized and activated early,from day 7 after stroke,but did not maintain a phagocytic state over time.Meanwhile,astrocytes showed relatively delayed mobilization and a moderate response to Wallerian degeneration.Moreover,no anterograde degeneration of spinal anterior horn cells was observed in response to Wallerian degeneration of the corticospinal tract.In conclusion,our data provide evidence for dynamic,pathogenic spatiotemporal changes in major cellular components of the corticospinal tract during Wallerian degeneration. 展开更多
关键词 corticospinal tract green fluorescent protein MICROGLIA spinal anterior horn cells stroke virus trace Wallerian degeneration
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Low-cost synthesis of high-purity Li_(2)S for sulfide solid state electrolytes enabled by polyvinyl alcohol 被引量:3
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作者 WU Zhuang-zhi HAN Cheng +3 位作者 WANG Jia-sen LI Xue-bao fei hao WANG De-zhi 《Journal of Central South University》 CSCD 2024年第12期4449-4459,共11页
Sulfide solid electrolytes(S-SEs)are widely preferred for their high ionic conductivity and processability.However,the further development of S-SEs is hindered by the excessive price of its critical raw materials of L... Sulfide solid electrolytes(S-SEs)are widely preferred for their high ionic conductivity and processability.However,the further development of S-SEs is hindered by the excessive price of its critical raw materials of Li_(2)S.Herein,a low-cost and environmentally friendly method is proposed to synthesize Li_(2)S by the carbothermal reduction reaction of Li_(2)SO_(4)in one step,and the effects of various factors are also discussed.As a result,a purity of 99.67%is obtained over the self-prepared Li_(2)S.More importantly,the cost of the self-prepared Li_(2)S is only about 50$/kg,which is significantly lower than that of the commercial counterpart(10000−15000 dollar/kg).Moreover,the ionic conductivity of Li_(5.5)PS_(4.5)Cl_(1.5)prepared using self-prepared Li_(2)S as raw materials is 4.19 mS/cm at room temperature,which is a little higher than that of Li_(5.5)PS_(4.5)Cl_(1.5)using commercial Li_(2)S(4.05 mS/cm).And the all-solid-state lithium batteries(ASSLBs)with the as-prepared electrolytes could maintain a discharge capacity of 109.9 mA·h/g with an average coulombic efficiency(CE)of 98%after 100 cycles at 0.2 C,which is equivalent to that using commercial Li_(2)S,demonstrating that the preparation strategy of Li_(2)S proposed in this work is feasible. 展开更多
关键词 lithium sulfide one-step preparation sulfide solid-state electrolytes all-solid-state lithium battery carbothermal reduction low-cost preparation
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Synergistic effect of carbon nanotube and encapsulated carbon layer enabling high-performance SnS_2-based anode for lithium storage 被引量:1
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作者 Chunwei Dong Yongjin Xia +7 位作者 Zhijiang Su Zhihua Han Yang Dong Jingyun Chen fei hao Qiyao Yu Qing Jiang Jiaye Ye 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期700-709,I0015,共11页
Tin disulfide(SnS_(2)),due to large interlayer spacing and high theoretical capacity,is regarded as a prospective anode material for lithium-ion batteries.Nevertheless,the poor electron conductivity of SnS_(2) and hug... Tin disulfide(SnS_(2)),due to large interlayer spacing and high theoretical capacity,is regarded as a prospective anode material for lithium-ion batteries.Nevertheless,the poor electron conductivity of SnS_(2) and huge volumetric change during the lithiation/delithiation process lead to a rapid capacity decay of the battery,hindering its commercialization.To address these issues,herein,SnS_(2) is in-situ grown on the surface of carbon nanotubes(CNT)and then encapsulated with a layer of porous amorphous carbon(CNT/SnS_(2)@C)by simple solvothermal and further carbonization treatment.The synergistic effect of CNT and porous carbon layer not only enhances the electrical co nductivity of SnS_(2) but also limits the huge volumetric change to avoid the pulverization and detachment of SnS_(2).Density functional theo ry calculations show that CNT/SnS_(2)@C has high Li^(+)adsorption and lithium storage capacity achieving high reaction kinetics.Consequently,cells with the CNT/SnS_(2)@C anode exhibit a high lithium storage capacity of 837mAh/g after 100 cycles at 0.1 A/g and retaining a capacity of 529.8 mAh/g under 1.0 A/g after 1000 cycles.This study provides a fundamental understanding of the electrochemical processes and beneficial guidance to design high-performance SnS_(2)-based anodes for LIBs. 展开更多
关键词 Lithium-ion batteries Porous amorphous carbon Carbon nanotubes SnS_(2)-based anode Density functional theory calculations
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基于工业互联网平台的核电运行数据服务研究 被引量:2
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作者 程敏敏 朱灿 +2 位作者 何栓 费淏 於泽辰 《网络安全与数据治理》 2024年第8期49-55,共7页
在核电行业数字化转型的进程中,核电工业互联网平台的建设至关重要。然而,现行统一数据平台存在子系统研发分散、外部接入复杂等问题,影响了开发和维护效率。针对这些问题,提出了一种核电工业互联网平台的实时数据服务管理机制,包括数... 在核电行业数字化转型的进程中,核电工业互联网平台的建设至关重要。然而,现行统一数据平台存在子系统研发分散、外部接入复杂等问题,影响了开发和维护效率。针对这些问题,提出了一种核电工业互联网平台的实时数据服务管理机制,包括数据服务目录管理、多维标签及查询技术,以及面向核电场景的多源异构数据分发和调度技术。研究结果表明,该平台能够提供统一、可视化、自助式、安全的实时数据服务。平台已成功应用于多个核电厂,支持21类服务和200个以上数据接口,有效满足了数字化应用的数据服务需求。该研究不仅为核电行业提供了实时、安全、高效的数据服务解决方案,也为其他工业领域的实时数据服务提供了参考。 展开更多
关键词 工业互联网 数据服务 多源异构 资源共享
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基于携带盐腐蚀介质的再生骨料混凝土性能劣化研究
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作者 何涛 卜久生 +1 位作者 费浩 张亚光 《北方交通》 2024年第4期49-52,56,共5页
为量化分析盐腐蚀再生混凝土骨料对再生混凝土性能的影响,进行室内试验,采用浓度为3%、5%和7%的盐溶液持续浸泡再生粗骨料,并采用不同取代率的再生粗骨料分别替代天然骨料拌制再生混凝土,借助抗压强度、劈裂强度试验和抗氯离子渗透试验... 为量化分析盐腐蚀再生混凝土骨料对再生混凝土性能的影响,进行室内试验,采用浓度为3%、5%和7%的盐溶液持续浸泡再生粗骨料,并采用不同取代率的再生粗骨料分别替代天然骨料拌制再生混凝土,借助抗压强度、劈裂强度试验和抗氯离子渗透试验获取不同再生混凝土的强度和耐久性演变规律。试验结果表明:携带盐腐蚀介质的再生粗骨料用于混凝土中,可影响再生混凝土的力学强度,混凝土的早期强度略微改善,而后期力学强度遭到劣化。 展开更多
关键词 再生骨料 盐腐蚀介质 再生混凝土 粗骨料
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表面渗氧强化对TC4钛合金力学性能的影响 被引量:4
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作者 冒海荣 费昊 +1 位作者 姜勇 巩建鸣 《南京工业大学学报(自然科学版)》 CAS 北大核心 2022年第6期640-646,共7页
采用氧增强扩散渗氧强化技术对TC4钛合金进行表面强化处理,利用显微硬度计测量渗氧层中的硬度分布,利用光学显微镜(OP)研究渗氧前后材料的微观组织变化,通过单轴拉伸试验研究表面渗氧强化处理对材料力学性能的影响。结果表明:经渗氧强... 采用氧增强扩散渗氧强化技术对TC4钛合金进行表面强化处理,利用显微硬度计测量渗氧层中的硬度分布,利用光学显微镜(OP)研究渗氧前后材料的微观组织变化,通过单轴拉伸试验研究表面渗氧强化处理对材料力学性能的影响。结果表明:经渗氧强化处理后,表面形成约150μm的渗氧强化层,表面硬度较基体提高一倍以上,约为950 HV,但力学性能下降明显,其中屈服强度下降约16%,抗拉强度下降约13%,延伸率下降约35%。材料力学性能降低的原因主要是渗氧强化处理过程中的高温作用,导致基体晶粒长大;表面渗氧强化层在小应变阶段即发生脆性开裂。 展开更多
关键词 TC4钛合金 力学性能 渗氧强化层 表面渗氧强化 脆性开裂 氧增强扩散
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以改良方法制作软骨细胞外基质构建高质量组织工程软骨 被引量:2
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作者 费毫 翟晨骏 +2 位作者 王振 张啸 范卫民 《南京医科大学学报(自然科学版)》 CAS CSCD 北大核心 2018年第7期934-939,987,共7页
目的:探讨应用改良方法制作的软骨细胞外基质(extracellular matrix,ECM)能否构建高质量组织工程软骨。方法:应用传统匀浆-脱细胞方法制作软骨ECM粉末,在此基础上通过物理研磨颗粒筛选获得细腻的软骨细胞外基质粉末(fine extracellular ... 目的:探讨应用改良方法制作的软骨细胞外基质(extracellular matrix,ECM)能否构建高质量组织工程软骨。方法:应用传统匀浆-脱细胞方法制作软骨ECM粉末,在此基础上通过物理研磨颗粒筛选获得细腻的软骨细胞外基质粉末(fine extracellular matrix,FECM)。将两种粉末通过冷冻干燥法制成ECM支架和FECM支架作为对照组和实验组。以软骨组织工程中成熟应用的聚乳酸聚羟基乙酸聚合物[poly(lactic-co-glycolic acid),PLGA]支架为阳性对照组。取等量大鼠骨髓间充质干细胞(bone marrow mesenchymal stem cells,BMSCs)种植于ECM支架和FECM支架,同时将BMSCs诱导分化为软骨细胞后种植于PLGA支架,然后将3种细胞-支架复合物移植入裸鼠皮下,28 d后取出样本并进行相关检测。结果:FECM支架孔径均一,结构规整,其构建的组织工程软骨在大小、色泽、糖胺多糖(s GAG)分泌以及胶原沉积等方面均远优于对照组构建的组织工程软骨,与阳性对照组无明显差异。结论:由改良方法制作的FECM支架在无外源性转化生长因子-β1(transforming growth factor-β1,TGF-β1)情况下可构建出高质量的组织工程软骨,具有潜在的临床应用价值。 展开更多
关键词 组织工程 软骨细胞外基质 细胞-支架复合物
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响应气候变化的棉花生长模拟与县域尺度产量评估 被引量:1
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作者 孟文博 王德胜 +4 位作者 张楠楠 费浩 唐梓涯 王涛 白铁成 《核农学报》 CAS CSCD 北大核心 2021年第7期1648-1657,共10页
为评估气象变化对棉花生长和县域尺度产量的影响,使用校正的CROPGRO-Cotton模型实现棉花生长模拟和响应气候变化的年际籽棉产量评估。2018年和2019年的田间试验数据被用于校正和验证CROPGRO-Cotton模型,结果表明校正的CROPGRO-Cotton模... 为评估气象变化对棉花生长和县域尺度产量的影响,使用校正的CROPGRO-Cotton模型实现棉花生长模拟和响应气候变化的年际籽棉产量评估。2018年和2019年的田间试验数据被用于校正和验证CROPGRO-Cotton模型,结果表明校正的CROPGRO-Cotton模型对物候发育期模拟精度较好,出苗期、开花期、结铃期和吐絮期的模拟误差分别为+1、+3、+1和-2 d。模拟的生长期地上总产量(TAGP)和叶面积指数(LAI)与实测值吻合较好,D值为0.99,模拟的RMSE值分别为718 kg·hm^(-2)和0.29 m^(2)·m^(-2),显示了较高的TAGP模拟精度(10%<NRMSE≤20%)和极高的LAI模拟精度(NRMSE≤10%)。2002―2017年南疆19个县的官方统计产量被用于验证模型的区域模拟性能,结果表明,校正的棉花生长模型具有较高的全局估产性能,D值为0.55,NRMSE值为15.8%。不同年际籽棉产量评估的平均D值和NRMSE值分别为0.48和15.6%,不同区域的籽棉产量评估的平均D值和NRMSE值分别为0.44和16.8%,校正的模型均获得了较高的年际和区域产量评估精度(NRMSE≤20%)。研究结果可为分析气候变化对棉花生长和产量的影响提供一种定量分析方法。 展开更多
关键词 棉花 CROPGRO-Cotton 气候变化 产量估算 生长模拟
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基于动态句法剪枝机制的中文语义角色标注 被引量:3
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作者 费豪 姬东鸿 任亚峰 《计算机学报》 EI CAS CSCD 北大核心 2022年第8期1746-1764,共19页
语义角色标注(Semantic Role Labeling,SRL)旨在识别给定句子中所包含的谓词及对应的语义论元,从而为信息抽取、自动问答和阅读理解等任务的语义理解提供帮助.构建句法特征作为实现语义角色标注任务的关键步骤,在很大程度上影响着任务... 语义角色标注(Semantic Role Labeling,SRL)旨在识别给定句子中所包含的谓词及对应的语义论元,从而为信息抽取、自动问答和阅读理解等任务的语义理解提供帮助.构建句法特征作为实现语义角色标注任务的关键步骤,在很大程度上影响着任务的性能.针对现有的神经网络模型未能有效构建句法特征,例如现有研究采取离线式的人工定式句法裁剪方案,不可避免地造成关键句法信息丢失或者裁剪效果减弱等问题,本文提出基于动态句法剪枝机制的端到端神经网络模型,并将其用于中文语义角色标注任务.具体地,我们提出两种创新的动态句法剪枝机制:基于递归神经网络模型的动态句法剪枝机制(Recur-DSP)和基于带句法标签的图卷积网络模型的句法剪枝机制(SGCN-DSP).Recur-DSP采用递归神经网络模型进行句法结构编码与融合,并对句法树的每一个连接处通过Gumbel-Softmax函数离散化实现动态句法裁剪.SGCN-DSP采用图卷积神经网络模型为句法依存树的依存弧结构以及对应的标签进行统一建模,并提出对应的动态句法裁剪机制.在基准数据集上的实验结果显示所提方法超过当前的最好模型,获得当前中文语义角色标注的最优性能.通过整合预训练语言模型BERT,基于CoNLL09数据集,提出的模型SGCN-DSP在角色论元识别上获得了90.4%的F1值,在谓词识别上获得90.8%的F1值. 展开更多
关键词 自然语言处理 语义角色标注 句法剪枝 神经网络 深度学习
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Biomimetic chitosan scaffolds with long-term controlled release of nerve growth factor repairs 20-mm-long sciatic nerve defects in rats 被引量:7
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作者 Fa-Dong Liu Hong-Mei Duan +5 位作者 fei hao Wen Zhao Yu-Dan Gao Peng hao Zhao-Yang Yang Xiao-Guang Li 《Neural Regeneration Research》 SCIE CAS CSCD 2022年第5期1146-1155,共10页
Although autogenous nerve transplantation is the gold standard for treating peripheral nerve defects of considerable length,it still has some shortcomings,such as insufficient donors and secondary injury.Composite chi... Although autogenous nerve transplantation is the gold standard for treating peripheral nerve defects of considerable length,it still has some shortcomings,such as insufficient donors and secondary injury.Composite chitosan scaffolds loaded with controlled release of nerve growth factor can promote neuronal survival and axonal regeneration after short-segment sciatic nerve defects.However,the effects on extended nerve defects remain poorly understood.In this study,we used chitosan scaffolds loaded with nerve growth factor for 8 weeks to repair long-segment(20 mm)sciatic nerve defects in adult rats.The results showed that treatment markedly promoted the recovery of motor and sensory functions.The regenerated sciatic nerve not only reconnected with neurons but neural circuits with the central nervous system were also reconstructed.In addition,the regenerated sciatic nerve reconnected the motor endplate with the target muscle.Therefore,this novel biomimetic scaffold can promote the regeneration of extended sciatic nerve defects and reconstruct functional circuits.This provides a promising method for the clinical treatment of extended peripheral nerve injury.This study was approved by the Animal Ethics Committee of Capital Medical University,China(approval No.AEEI-2017-033)on March 21,2017. 展开更多
关键词 AXON CHITOSAN functional recovery myelin sheath nerve growth factor peripheral nerve injury pseudorabies virus regeneration SCAFFOLD sciatic nerve
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Hepatitis C virus may infect extrahepatic tissues in patients with hepatitis C 被引量:3
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作者 Fu Ming Yan An Shen Chen +5 位作者 fei hao Xi Ping Zhao Chang Hai Gu Li Bin Zhao Dong Liang Yang Lian Jie hao 《World Journal of Gastroenterology》 SCIE CAS CSCD 2000年第6期805-811,共7页
AIM To explore the status of extrahepatichepatitis C virus(HCV)infection and replicationin hepatitis C patients,and its potentialimplication in HCV infection and pathogenicity.METHODS By reverse-transcriptase poly-mer... AIM To explore the status of extrahepatichepatitis C virus(HCV)infection and replicationin hepatitis C patients,and its potentialimplication in HCV infection and pathogenicity.METHODS By reverse-transcriptase poly-merase chain reaction(RT-PCR),in situhybridization(ISH)and immunohistochemistry,HCV RNA,HCV replicative intermediate(minus-strand of HCV RNA),and HCV antigens weredetected in 38 autopsy extrahepatic tissuespecimens(including 9 kidneys,9 hearts,9pancreas,5 intestines,2 adrenal glands,2spleens,1 lymph node,and 1 gallbladder)from 9hepatitis C patients,respectively;and thestatus of HCV replication in extrahepatic tissueswas studied.RESULTS By RT-PCR,all 9 patients werepositive for HCV RNA in kidney,heart,pancreas,and intestine,but only 6(66.7%)patients were positive for HCV replicativeintermediate.HCV RNA and HCV antigens weredetected in kidney,heart,pancreas,intestine,adrenal gland,lymph node,and gallbladder in 5(55.6%)and 6(66.7%)patients by ISH andimmunohistochemistry,respectively.HCV RNA and HCV antigens were not detected in theseextrahepatic organs in 3(33.3%)patients,although their livers were positive for HCV.HCVreplicative intermediate detected by RT-PCR wasconsistent with HCV RNA and HCV antigensdetected by ISH and immunohistochemistry(Kappa=0.42-0.75).HCV RNA and HCVantigens were detected in myocardial cells,epithelial cells of intestinal gladular,interstitialcells of kidney,epithelial cells of tubules andglomerulus,pancreas acinar cells and epithelialcells of pancreatic duct,epithelial cells ofmucous membrane sinus of gallbladder,cortexand medulla cells in adrenal gland,andmononuclear cells in lymph node.HCV RNA wasalso detected in bile duct epithelial cells,sinusoidal cells,and mononuclear cells in livertissues by ISH.CONCLUSION HCV can infect extrahepatictissues,and many various tissue cells maysupport HCV replication;extrahepatic HCVinfection and replication may be of'concomitantstate'in most of patients with hepatitis C.Theinfected extrahepatic tissues might act as areservoir for HCV,and play a role in both HCVpersistence and reactivation of infection.HCVas an etiologic agent replicating and expressingviral proteins in extrahepatic tissues itselfcontributes to extrahepatic syndromeassociated.HCV infection in a few patients withchronic HCV infection. 展开更多
关键词 HEPATITIS C virus HEPATITIS C ANTIGENS in SITU hybridization immunohistochemistry RNA polymerase chain reaction antibodies monoclonal DIGOXIGENIN
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小剂量多巴胺联合多巴酚丁胺辅助治疗小儿重症肺炎的临床效果分析 被引量:4
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作者 费浩 郭晓梅 《数理医药学杂志》 2019年第11期1669-1670,共2页
目的:分析研究在小儿重症肺炎治疗过程中采取小剂量多巴胺联合多巴酚丁胺辅助治疗的疗效。方法:选择从2016年1月~2018年1月在某院治疗的50例小儿重症肺炎患者作为本次研究对象,随机分为对照组与观察组,各25例。对照组采取常规治疗,观察... 目的:分析研究在小儿重症肺炎治疗过程中采取小剂量多巴胺联合多巴酚丁胺辅助治疗的疗效。方法:选择从2016年1月~2018年1月在某院治疗的50例小儿重症肺炎患者作为本次研究对象,随机分为对照组与观察组,各25例。对照组采取常规治疗,观察组在对照组基础上采取小剂量多巴胺联合多巴酚丁胺辅助治疗,观察这两组患者的临床效果。结果:观察组治疗总有效率高于对照组(P<0.05);观察组患者的心率、呼吸、发热、肺啰音消失、住院时间均短于对照组(P<0.05)。结论:在治疗小儿重症肺炎方面,小剂量多巴胺联合多巴酚丁胺效果更好,值得临床推广使用。 展开更多
关键词 小儿重症肺炎 小剂量多巴胺 多巴酚丁胺 疗效
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Adult Mammalian Neurogenesis:Hopes and Challenges in the Repair of Spinal Cord Injury
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作者 Zhaoyang Yang Wen Zhao +4 位作者 Yudan Gao Hongmei Duan Peng hao fei hao Xiaoguang Li 《Engineering》 SCIE EI 2021年第12期1713-1714,共2页
Adult endogenous neurogenesis was first defined as the generation of neurons and glia cells in the central nervous system(CNS);it was subsequently referred to as the activation of endogenous neural stem cells,and ulti... Adult endogenous neurogenesis was first defined as the generation of neurons and glia cells in the central nervous system(CNS);it was subsequently referred to as the activation of endogenous neural stem cells,and ultimately limited to the generation of new neurons[1].The research team led by Xiaoguang Li enriched this concept in 2015:Endogenous neural stem cells in the adult CNS can be activated,recruited,and migrated to the injured area,where these stem cells further differentiate into mature neurons. 展开更多
关键词 ENDOGENOUS SPINAL neural
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