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深度神经网络修复策略综述 被引量:1
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作者 梁震 刘万伟 +3 位作者 吴陶然 薛白 王戟 杨文婧 《软件学报》 EI CSCD 北大核心 2024年第3期1231-1256,共26页
随着智能信息时代的发展,深度神经网络在人类社会众多领域中的应用,尤其是在自动驾驶、军事国防等安全攸关系统中的部署,引起了学术界和工业界对神经网络模型可能表现出的错误行为的担忧.虽然神经网络验证和神经网络测试可以提供关于错... 随着智能信息时代的发展,深度神经网络在人类社会众多领域中的应用,尤其是在自动驾驶、军事国防等安全攸关系统中的部署,引起了学术界和工业界对神经网络模型可能表现出的错误行为的担忧.虽然神经网络验证和神经网络测试可以提供关于错误行为的定性或者定量结论,但这种事后分析并不能防止错误行为的发生,如何修复表现出错误行为的预训练神经网络模型依然是极具挑战性的问题.为此,深度神经网络修复这一领域应运而生,旨在消除有缺陷的神经网络产生的错误预测,使得神经网络满足特定的规约性质.目前为止,典型的神经网络修复范式有3种:重训练、无错误定位的微调和包含错误定位的微调.介绍深度神经网络的发展和神经网络修复的必要性;厘清相近概念;明确神经网络修复的挑战;详尽地调研目前已有的神经网络修复策略,并对内在联系与区别进行分析和比较;调研整理神经网络修复策略常用的评价指标和基准测试;展望未来神经网络修复领域研究中需要重点关注的可行方向. 展开更多
关键词 深度神经网络修复 错误行为 重训练 微调 错误定位
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缓释尿素对育肥牦牛生产性能和屠宰性能的影响
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作者 申文兵 王之盛 +6 位作者 薛白 王立志 胡瑞 邹华围 姜雅慧 肖鉴鑫 彭全辉 《饲料工业》 CAS 北大核心 2024年第16期60-65,共6页
试验考察了在饲粮中添加缓释尿素对育肥牦牛生产性能、屠宰性能以及血液生化指标的影响。选择健康体重相近[(277.9±10.4)kg]麦洼公牦牛24头,分为3个处理组,分别为对照组:饲喂原场全混合饲粮(代谢能11.03 MJ/kg,CP 10%);0.5%组:添... 试验考察了在饲粮中添加缓释尿素对育肥牦牛生产性能、屠宰性能以及血液生化指标的影响。选择健康体重相近[(277.9±10.4)kg]麦洼公牦牛24头,分为3个处理组,分别为对照组:饲喂原场全混合饲粮(代谢能11.03 MJ/kg,CP 10%);0.5%组:添加玉米干酒糟及其可溶物(DDGS)替代部分粗饲料,降低饲粮中粗料水平,并添加0.5%缓释尿素(TMR的代谢能11.35 MJ/kg,CP 12.77%);1.0%组:利用玉米DDGS替代饲粮中的豆粕和菜粕,并添加1.0%缓释尿素(TMR的代谢能11.42 MJ/kg,CP 12.77%)。牦牛预试期10 d,正试期60 d,在第60天晨饲前收集血清进行指标测定。结果表明:①0.5%组平均日增重高于对照组(P<0.05)。②0.5%组和1.0%组的谷丙转氨酶活性高于对照组(P<0.05),1.0%组高于0.5%组(P<0.05);1.0%组的谷草转氨酶活性高于对照组(P<0.05);1.0%组的血氨浓度高于对照组(P<0.05);1.0%组血浆尿素氮浓度高于0.5%组和对照组(P<0.05)。③0.5%组屠宰率和净肉率分别比对照组高1.1和1.4个百分点(P>0.05)。④0.5%组和1.0%组经济效益较对照组分别提高24.03%和29.96%。联合运用1.0%缓释尿素和玉米DDGS可以完全替代育肥牦牛日粮中的豆粕和菜粕并提高养殖经济效益。 展开更多
关键词 牦牛 缓释尿素 血氨 生产性能 屠宰性能
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酸化处理对代乳粉乳品质和微生物群落的影响
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作者 王春辉 罗焱鹏 +7 位作者 王之盛 薛白 王立志 邹华围 胡瑞 姜雅慧 肖鉴鑫 彭全辉 《中国奶牛》 2024年第9期6-12,共7页
本文考察了酸化处理对代乳粉乳品质和微生物群落的影响。试验分为2个组,分别为对照组和酸化处理组,每个组8个重复,酸化处理组采用酸化剂将乳pH调至4.0~4.5,两组乳配制好后分别于室温放置12、24和48h并采样,对乳成分进行测定和微生物组... 本文考察了酸化处理对代乳粉乳品质和微生物群落的影响。试验分为2个组,分别为对照组和酸化处理组,每个组8个重复,酸化处理组采用酸化剂将乳pH调至4.0~4.5,两组乳配制好后分别于室温放置12、24和48h并采样,对乳成分进行测定和微生物组成进行16S rRNA基因测序。结果表明:(1)12h时,酸化处理组的乳糖、乳脂显著低于对照组(P<0.05),乳蛋白含量显著高于对照组(P<0.05)。24h时,酸化处理组的乳脂和非脂乳固体含量低于对照组(P<0.05)。48h时,酸化处理组的乳糖、乳脂和非脂乳固体含量低于对照组(P<0.05)。随着时间的延长,两组乳的乳糖、乳脂和非脂乳固体含量降低(P<0.05),而乳蛋白含量随着时间的延长而上升(P<0.05)。两组乳的pH值均随着时间的延长而降低(P<0.05)。(2)相同时间点下,酸化处理组的α多样性Chao1、ACE、Shannon和Simpson指数显著高于对照组(P<0.05)。酸化处理组和对照组各时间点下的细菌群落结构差异显著(P<0.05)。各时间段中,酸化处理组中拟杆菌门、异常球菌-栖热菌门、放线菌门相对丰度均大于对照组(P<0.05);变形菌门的相对丰度在对照组中随时间延长显著升高(P<0.05),而在酸化处理组则显著降低(P<0.05)。酸化处理组中有益菌属如链球菌属、乳酸球菌属、乳杆菌属和厌氧芽孢杆菌属的丰度各时间点均高于对照组(P<0.05),杆菌属、泛菌属和肠球菌属丰度低于对照组(P<0.05)。综上,代乳粉进行酸化处理后改变了乳中菌群结构,提高了有益菌属的相对丰度,降低了有害菌丰度,较好地保存了乳中营养组分。 展开更多
关键词 代乳粉 酸化处理 乳品质 微生物群落
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Responses of growth performance,antioxidant function,small intestinal morphology and mRNA expression of jejunal tight junction protein to dietary iron in yellow-feathered broilers 被引量:1
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作者 Kaiwen Lei Hao Wu +4 位作者 Jerry W Spears Xi Lin Xi Wang xue bai Yanling Huang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1329-1337,共9页
This study aimed to investigate the dose-effect of iron on growth performance,antioxidant function.intestinal morphology,and mRNA expression of jejunal tight junction protein in 1-to21-d-old yellow-feathered broilers.... This study aimed to investigate the dose-effect of iron on growth performance,antioxidant function.intestinal morphology,and mRNA expression of jejunal tight junction protein in 1-to21-d-old yellow-feathered broilers.A total of 7201-d-old yellow-feathered maleb roilers were allocated to 9 treatments with 8 replicate cages of 10 birds per cage.The dietary treatments were consisted of a basal diet(contained 79.6 mg Fe kg^(-1))supplemented with 0,20,40,60,80,160,320,640,and 1,280 mg Fe kg^(-1)in the form of FeSO_(4)·7H_(2)O.Compared with the birds in the control group,birds supplemented with 20mg Fe kg^(-1)had higher average daily gain(ADG)(P<0.0001).Adding 640 and 1,280 mg Fe kg^(-1)significantly decreased ADG(P<0.0001)and average daily feed intake(ADFI)(P<0.0001)compared with supplementation of 20mg Fe kg^(-1).Malondialdehyde(MDA)concentration in plasma and duodenum increased linearly(P<0.0001),but MDA concentration in liver and jejunum increased linearly(P<0.05)or quadratically(P<0.05)with increased dietary Fe concentration.The villus height(VH)in duodenum and jejunum,and the ratio of villus height to crypt depth(V/C)in duodenum decreased linearly(P?0.05)as dietary Feincreased.As dietary Fe increased,the jejunal relative mRNA abundance of claudin-1 decreased linearly(P=0.001),but the jejunal relative mRNA abundance of zona occludens-1(ZO-1)and occludin decreased linearly(P?0.05)or quadratically(P?0.05).Compared with the supplementation of 20 mg Fe kg^(-1),the supplementation of640 mg Fe kg^(-1)or higher increased(P?0.05)MDA concentrations in plasma,duodenum,and jejunum,decreased VH in the duodenum and jejunum,and the addition of 1,280 mg Fe kg^(-1)reduced(P?0.05)the jejunal tight junction protein(claudin-1,ZO-1,occludin)mRNA abundance.In summary,640 mg of supplemental Fe kg^(-1)or greater was associated with decreased growth performance,increased oxidative stress,disrupted intestinal morphology,and reduced mRNA expression of jejunal tight junction protein. 展开更多
关键词 IRON yellow-feathered broiler antioxidant function intestinal morphology tight junction protein
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饲粮不同代谢能和蛋白质水平对育成期云上黑山羊生长性能、能氮代谢和血清生化指标的影响
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作者 付斌龙 旦增白吉 +6 位作者 赵小琪 薛白 兰蓉 曹堂兵 江炎庭 邵庆勇 欧阳依娜 《动物营养学报》 CAS CSCD 北大核心 2024年第8期5229-5241,共13页
本试验旨在研究饲粮不同代谢能和蛋白质水平对育成期云上黑山羊生长性能、能氮代谢和血清生化指标的影响。选取80只体况良好、体重相近的6月龄云上黑山羊公羊,随机分为4组,每组20只羊。设定饲粮代谢能水平分别为9.8(高)、8.2 MJ/kg(低)... 本试验旨在研究饲粮不同代谢能和蛋白质水平对育成期云上黑山羊生长性能、能氮代谢和血清生化指标的影响。选取80只体况良好、体重相近的6月龄云上黑山羊公羊,随机分为4组,每组20只羊。设定饲粮代谢能水平分别为9.8(高)、8.2 MJ/kg(低),蛋白质水平分别为13%(高)、10%(低),配制4种试验饲粮。4组试验羊分别饲喂高代谢能高蛋白质饲粮(HEHP组)、高代谢能低蛋白质饲粮(HELP组)、低代谢能高蛋白质饲粮(LEHP组)和低代谢能低蛋白质饲粮(LELP组)。所有试验羊经14 d的预试期后进入50 d的正试期,在正试期第23天从各组中选取5只羊进行为期5 d的消化代谢试验。结果显示:1)HELP组的平均日增重、干物质采食量显著高于LEHP组和LELP组(P<0.05);HELP组的料重比最低,且显著低于LELP组(P<0.05)。2)HELP组的沉积氮和净蛋白质利用率显著高于LELP组(P<0.05)。3)HELP组的总能消化率、总能代谢率、消化能代谢率均显著高于LEHP组和LELP组(P<0.05)。4)HELP组血清葡萄糖、总蛋白、白蛋白含量最高,且显著高于LELP组(P<0.05);HELP组血清尿素氮含量显著低于HEHP组和LEHP组(P<0.05)。5)HELP组增重效益最高,为4.759元/(d·只),LELP组增重效益最低,为2.380元/(d·只)。综上所述,饲喂代谢能水平为9.8 MJ/kg、蛋白质水平为10%的饲粮时有利于维持育成期云上黑山羊机体正常生理功能,并能促进其对营养物质的消化吸收,提高平均日增重和增重效益。 展开更多
关键词 代谢能 蛋白质 云上黑山羊 生长性能 能氮代谢 血清生化指标
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Ginsenoside Rk3 modulates gut microbiota and regulates immune response of group 3 innate lymphoid cells to against colorectal tumorigenesis 被引量:1
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作者 xue bai Rongzhan Fu +5 位作者 Yannan Liu Jianjun Deng Qiang Fei Zhiguang Duan Chenhui Zhu Daidi Fan 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第2期259-275,共17页
The gut microbiota plays a pivotal role in the immunomodulatory and protumorigenic microenvironment of colorectal cancer(CRC).However,the effect of ginsenoside Rk3(Rk3)on CRC and gut microbiota remains unclear.Therefo... The gut microbiota plays a pivotal role in the immunomodulatory and protumorigenic microenvironment of colorectal cancer(CRC).However,the effect of ginsenoside Rk3(Rk3)on CRC and gut microbiota remains unclear.Therefore,the purpose of this study is to explore the potential effect of Rk3 on CRC from the perspective of gut microbiota and immune regulation.Our results reveal that treatment with Rk3 significantly suppresses the formation of colon tumors,repairs intestinal barrier damage,and regulates the gut microbiota imbalance caused by CRC,including enrichment of probiotics such as Akkermansia muciniphila and Barnesiella intestinihominis,and clearance of pathogenic Desulfovibrio.Subsequent metabolomics data demonstrate that Rk3 can modulate the metabolism of amino acids and bile acids,particularly by upregulating glutamine,which has the potential to regulate the immune response.Furthermore,we elucidate the regulatory effects of Rk3 on chemokines and inflammatory factors associated with group 3 innate lymphoid cells(ILC3s)and T helper 17(Th17)signaling pathways,which inhibits the hyperactivation of the Janus kinase-signal transducer and activator of transcription 3(JAK-STAT3)signaling pathway.These results indicate that Rk3 modulates gut microbiota,regulates ILC3s immune response,and inhibits the JAK-STAT3 signaling pathway to suppress the development of colon tumors.More importantly,the results of fecal microbiota transplantation suggest that the inhibitory effect of Rk3 on colon tumors and its regulation of ILC3 immune responses are mediated by the gut microbiota.In summary,these findings emphasize that Rk3 can be utilized as a regulator of the gut microbiota for the prevention and treatment of CRC. 展开更多
关键词 Colorectal cancer GINSENOSIDE Immune cells Gut microbiota
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饲粮粗蛋白质水平对妊娠期云南半细毛羊养分表观消化率的影响
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作者 付斌龙 赵小琪 +4 位作者 倪晓君 旦增白吉 薛白 李卫娟 权国波 《中国饲料》 北大核心 2024年第19期81-89,共9页
为研究饲粮粗蛋白质(CP)水平对妊娠期云南半细毛羊养分表观消化率的影响,试验选取50只体况良好、年龄一致、配种日期相同、体重为(46.52±4.58)kg的经产2胎妊娠期云南半细毛羊,随机分为5组,每组10个重复,每个重复1只羊。从妊娠第46... 为研究饲粮粗蛋白质(CP)水平对妊娠期云南半细毛羊养分表观消化率的影响,试验选取50只体况良好、年龄一致、配种日期相同、体重为(46.52±4.58)kg的经产2胎妊娠期云南半细毛羊,随机分为5组,每组10个重复,每个重复1只羊。从妊娠第46天开始,进行预试期14 d和正试期90 d的饲养试验。在妊娠前期(正试期第1~30天)和中期(正试期第31~60天)对应的饲粮CP水平为6.65%(1组)、9.02%(2组)、10.97%(3组)、12.43%(4组)和13.95%(5组),妊娠后期(正试期第61~90天)对应的饲粮CP水平为6.31%(1组)、7.77%(2组)、10.47%(3组)、12.69%(4组)和15.25%(5组),在正试期第11~15天、第41~45天、第71~75天,分别从各组选5只试验羊开展为期5 d的消化代谢试验。结果表明:(1)在妊娠前期和中期,除第1组外,其余4个组干物质(DM)表观消化率无显著差异(P>0.05),在妊娠后期,第3组、第5组DM表观消化率较第1组分别提高了9.15%和7.25%(P<0.05)。(2)在妊娠前期,后3组氮(N)表观消化率较前2组至少提高34.25%以上(P<0.01),妊娠中期,第4组、第5组N表观消化率较前2组至少提高了43.66%以上(P<0.01),妊娠后期,第5组N表观消化率较第1组、第2组和第3组分别提高了61.88%、45.02%和19.07%(P<0.01)。(3)中性洗涤纤维(NDF)消化率随饲粮CP水平的升高而升高,妊娠前期,第4组、第5组NDF表观消化率较第1组分别提高了22.25%和21.06%(P<0.05),妊娠中期,后3组NDF表观消化率较第1组、第2组至少提高26.67%以上(P<0.01),妊娠后期,第4组、第5组NDF表观消化率较第1组、第2组至少提高30.67%以上(P<0.01)。(4)在妊娠前期,后4组酸性洗涤纤维(ADF)消化率较第1组至少提高31.26%(P<0.01),在妊娠中期,第5组ADF表观消化率较第1组提高了60.98%(P<0.01),在妊娠后期,第3组ADF表观消化率较第1组和第2组分别提高了50.20%和38.90%(P<0.01)。(5)整个妊娠期各组间的钙(Ca)和磷(P)消化率无显著差异(P>0.05)。(6)在妊娠前期,第2、3、4组的总能(GE)表观消化率较第5组分别提高了3.35%、2.90%和2.10%(P<0.05),而较第1组则分别提高了13.60%、12.41%和11.50%(P<0.01),妊娠中期和后期各组间GE表观消化率无显著差异(P>0.05)。综上所述,妊娠前、中、后三个时期,云南半细毛羊饲粮CP水平分别为10.97%、12.43%和15.25%时,饲粮N表观消化率最高,饲粮CP水平对Ca、P表观消化率无影响。 展开更多
关键词 云南半细毛羊 妊娠期 蛋白质 养分表观消化率
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Evolution of pore systems in low-maturity oil shales during thermal upgrading--Quantified by dynamic SEM and machine learning
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作者 Jun Liu xue bai Derek Elsworth 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期1739-1750,共12页
In-situ upgrading by heating is feasible for low-maturity shale oil,where the pore space dynamically evolves.We characterize this response for a heated substrate concurrently imaged by SEM.We systematically follow the... In-situ upgrading by heating is feasible for low-maturity shale oil,where the pore space dynamically evolves.We characterize this response for a heated substrate concurrently imaged by SEM.We systematically follow the evolution of pore quantity,size(length,width and cross-sectional area),orientation,shape(aspect ratio,roundness and solidity)and their anisotropy—interpreted by machine learning.Results indicate that heating generates new pores in both organic matter and inorganic minerals.However,the newly formed pores are smaller than the original pores and thus reduce average lengths and widths of the bedding-parallel pore system.Conversely,the average pore lengths and widths are increased in the bedding-perpendicular direction.Besides,heating increases the cross-sectional area of pores in low-maturity oil shales,where this growth tendency fluctuates at<300℃ but becomes steady at>300℃.In addition,the orientation and shape of the newly-formed heating-induced pores follow the habit of the original pores and follow the initial probability distributions of pore orientation and shape.Herein,limited anisotropy is detected in pore direction and shape,indicating similar modes of evolution both bedding-parallel and bedding-normal.We propose a straightforward but robust model to describe evolution of pore system in low-maturity oil shales during heating. 展开更多
关键词 Low-maturity oil shale Pore elongation Organic matter pyrolysis In-situthermal upgrading Scanning electron microscopy(SEM) Machine learning
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Multifunctional interfacial molecular bridge enabled by an aggregation-induced emission strategy for enhancing efficiency and UV stability of perovskite solar cells
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作者 Shuhang Bian Yuqi Wang +13 位作者 Fancong Zeng Zhongqi Liu Bin Liu Yanjie Wu Long Shao Yongzhi Shao Huan Zhang Shuainan Liu Jin Liang xue bai Lin Xu Donglei Zhou Biao Dong Hongwei Song 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期588-595,I0013,共9页
The interface defects between the electron transport layer(ETL)and the perovskite layer,as well as the low ultraviolet(UV)light utilization rate of the perovskite absorption layer,pose significant challenges for the c... The interface defects between the electron transport layer(ETL)and the perovskite layer,as well as the low ultraviolet(UV)light utilization rate of the perovskite absorption layer,pose significant challenges for the commercialization of perovskite solar cells(PSCs).To address this issue,this paper proposes an innovative multifunctional interface modulation strategy by introducing aggregation-induced emission(AIE)molecule 5-[4-[1,2,2-tri[4-(3,5-dicarboxyphenyl)phenyl]ethylene]phenyl]benzene-1,3-dicarboxylic acid(H_(8)ETTB)at the SnO_(2)ETL/perovskite interface.Firstly,the interaction of H_(8)ETTB with the SnO_(2)surface,facilitated by its carboxyl groups,is effective in passivating surface defects caused by noncoord inated Sn and O vacancies.This interaction enhances the conductivity of the SnO_(2)film and adjusts energy levels,leading to enhanced charge carrier transport.Simultaneously,H_(8)ETTB can passivate noncoord inated Pb^(2+)ions at the perovskite interface,promoting perovskite crystallization and reducing the interface energy barrier,resulting in a perovskite film with low defects and high crystalline quality.More importantly,the H_(8)ETTB molecule,can convert UV light into light absorbable by the perovskite,thereby reducing damage caused by UV light and improving the device's utilization of UV.Consequently,the champion PSC based on SnO_(2)-H_(8)ETTB achieves an impressing efficiency of 23.32%and significantly improved photostability compared with the control device after continuous exposure to intense UV radiation.In addition,the Cs_(0.05)(FA_(0.95)MA_(0.05))_(0.95)Pb(I_(0.95)Br_(0.05))_(3)based device can achieve maximum efficiency of 24.01%,demonstrating the effectiveness and universality of this strategy.Overall,this innovative interface bridging strategy effectively tackles interface defects and low UV light utilization in PSCs,presenting a promising approach for achieving highly efficient and stable PSCs. 展开更多
关键词 Perovskite solar cells Aggregation-induced emission Defect passivation EFFICIENCY UV stability
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Quantitative analysis of laser-generated ultrasonic wave characteristics and their correlation with grain size in polycrystalline materials
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作者 徐兆文 白雪 +2 位作者 马健 万壮壮 王超群 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期526-543,共18页
Quantitative relationship between nanosecond pulsed laser parameters and the characteristics of laser-generated ultrasonic waves in polycrystalline materials was evaluated.The high energy of the pulsed laser with a la... Quantitative relationship between nanosecond pulsed laser parameters and the characteristics of laser-generated ultrasonic waves in polycrystalline materials was evaluated.The high energy of the pulsed laser with a large irradiation spot simultaneously generated ultrasonic longitudinal and shear waves at the epicenter under the slight ablation regime.An optimized denoising technique based on wavelet thresholding and variational mode decomposition was applied to reduce noise in shear waves with a low signal-to-noise ratio.An approach for characterizing grain size was proposed using spectral central frequency ratio(SCFR)based on time-frequency analysis.The results demonstrate that the generation regime of ultrasonic waves is not solely determined by the laser power density;even at high power densities,a high energy with a large spot can generate an ultrasonic waveform dominated by the thermoelastic effect.This is ascribed to the intensification of the thermoelastic effect with the proportional increase in laser irradiation spot area for a given laser power density.Furthermore,both longitudinal and shear wave SCFRs are linearly related to grain size in polycrystalline materials;however,the shear wave SCFR is more sensitive to finer-grained materials.This study holds great significance for evaluating metal material properties using laser ultrasound. 展开更多
关键词 laser-ultrasonics polycrystalline materials ultrasonic time-frequency characteristics grain size
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Application prospects of urine-derived stem cells in neurological and musculoskeletal diseases
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作者 Hui-Si Yang Yue-Xiang Zheng +2 位作者 xue bai Xiu-Ying He Ting-Hua Wang 《World Journal of Orthopedics》 2024年第10期918-931,共14页
Urine-derived stem cells(USCs)are derived from urine and harbor the potential of proliferation and multidirectional differentiation.Moreover,USCs could be reprogrammed into pluripotent stem cells[namely urine-derived ... Urine-derived stem cells(USCs)are derived from urine and harbor the potential of proliferation and multidirectional differentiation.Moreover,USCs could be reprogrammed into pluripotent stem cells[namely urine-derived induced pluripotent stem cells(UiPSCs)]through transcription factors,such as octamer binding transcription factor 4,sex determining region Y-box 2,kruppel-like factor 4,myelocytomatosis oncogene,and Nanog homeobox and protein lin-28,in which the first four are known as Yamanaka factors.Mounting evidence supports that USCs and UiPSCs possess high potential of neurogenic,myogenic,and osteogenic differentiation,indicating that they may play a crucial role in the treatment of neurological and musculoskeletal diseases.Therefore,we summarized the origin and physiological characteristics of USCs and UiPSCs and their therapeutic application in neurological and musculoskeletal disorders in this review,which not only contributes to deepen our understanding of hallmarks of USCs and UiPSCs but also provides the theoretical basis for the treatment of neurological and musculoskeletal disorders with USCs and UiPSCs. 展开更多
关键词 Urine-derived stem cells Urine-derived induced pluripotent stem cells Neurological diseases Musculoskeletal diseases Treatment prospect
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食管癌新型生物学标志物的筛选以及外周血mRNA初步验证
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作者 薛白 陈平 +5 位作者 张玉领 邵启祥 许国莹 郝惠惠 李洪春 蔡伟莉 《临床检验杂志》 CAS 2024年第5期337-342,共6页
目的采用生物信息学和实时荧光定量PCR(qRT-PCR)筛选并验证对食管癌(ESCA)发生和发展起关键作用的基因,以期寻找ESCA的新型生物学标志物。方法检索TCGA数据库,利用韦恩图分析,初步确定ESCA样本中差异表达基因与对无病生存率(DFS)产生最... 目的采用生物信息学和实时荧光定量PCR(qRT-PCR)筛选并验证对食管癌(ESCA)发生和发展起关键作用的基因,以期寻找ESCA的新型生物学标志物。方法检索TCGA数据库,利用韦恩图分析,初步确定ESCA样本中差异表达基因与对无病生存率(DFS)产生最显著影响的基因之间的交叉基因。通过对重叠基因进行蛋白质-蛋白质互作(PPI)网络分析,并进行GO和KEGG功能分析,筛选出与ESCA发生、发展相关的关键潜在基因。利用qRT-PCR对ESCA患者外周血中关键基因mRNA的表达水平进行定量分析并结合患者临床病理参数进行统计学分析,以评估其作为ESCA新型生物学标志物的潜在价值。结果在TCGA数据库中筛选出的ESCA差异表达基因与无病生存基因交叉后,发现存在明显差异表达的基因59个,其中39个基因上调,20个基因下调,且上述基因均明显影响患者的DFS。经过PPI网络分析后,确定了15个核心互作的上调基因,而下调基因没有形成任何互作网络。进一步对这15个核心互作基因通过GO和KEGG富集分析,发现纤维连接蛋白1(FN1)可能是ESCA筛查的潜在生物学标志物。qRT-PCR结果显示,与健康人对照组相比,ESCA患者外周血中FN1 mRNA的表达水平显著升高。结合患者的临床病理参数分析,发现分化程度差、临床病理分期高的ESCA患者外周血FN1 mRNA水平明显升高,且证实FN1 mRNA水平模型能够有效区分食管癌患者和健康人。结论FN1 mRNA可作为ESCA潜在的非侵入性筛查生物学标志物。 展开更多
关键词 食管癌 纤维连接蛋白1 生物学标志物
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Optimization of Extraction Process for Total Flavonoids from Penthorum chinense Pursh and Comparison of Their Contents from Different Parts
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作者 Hongsheng LIU Jiqiang YAO +2 位作者 xue bai Jianying KANG Yefei YUAN 《Medicinal Plant》 2024年第2期10-14,共5页
[Objectives]This study was conducted to optimize the extraction process of total flavonoids from Penthorum chinense Pursh and compare their contents from different parts.[Methods]Single factor and orthogonal experimen... [Objectives]This study was conducted to optimize the extraction process of total flavonoids from Penthorum chinense Pursh and compare their contents from different parts.[Methods]Single factor and orthogonal experiments were designed to optimize the extraction process of total flavonoids from P.chinense Pursh with the volume fraction of ethanol,the ratio of material to liquid,heating reflux extraction time and extraction times as factors,and the content of total flavonoids as the index.A verification test was carried out.The optimized extraction process was adopted to compare the contents of total flavonoids from different parts of P.chinense Pursh.[Results]The best extraction process was extracting the powder of P.chinense Pursh for 2.0 h with 20 times of 55%ethanol by reflux twice.Under this condition,the contents of total flavonoids were 3.63%,8.90%,11.28%,and 4.36%from stems,leaves,flowers and whole grass of P.chinense Pursh,respectively.[Conclusions]The process is reasonable,feasible and stable,and can effectively extract total flavonoids from P.chinense Pursh.The contents of total flavonoids from different parts of P.chinense Pursh were quite different,and the value was higher in the leaves and flowers,so the proportions of leaves and flowers should be paid attention to in the industrial processing of P.chinense Pursh. 展开更多
关键词 Penthorum chinense Pursh Total flavonoids Orthogonal experiments Extraction process Content determination
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Sources of dissolved inorganic carbon in rivers from the Changbaishan area, an active volcanic zone in North Eastern China 被引量:2
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作者 xue bai Benjamin Chetelat Yilong Song 《Acta Geochimica》 EI CAS CSCD 2017年第3期410-415,共6页
Major elements and carbon isotopes of dissolved inorganic carbon(DIC)have been measured in the waters of Changbaishan mountain,a volcanic area in northeastern China,between June and September 2016 to decipher the orig... Major elements and carbon isotopes of dissolved inorganic carbon(DIC)have been measured in the waters of Changbaishan mountain,a volcanic area in northeastern China,between June and September 2016 to decipher the origin of the CO_2 involved in chemical weathering reactions.Spatial variations of major elements ratios measured in water samples can be explained by a change of the chemical composition of the volcanic rocks between the volcanic cone(trachytes)and the basaltic shield as evidenced by the variations in the composition of these rocks.Hence,DIC results from the neutralization of CO_2 by silicate rocks.DIC concentrations vary from 0.3 to 2.5 mmol/L and carbon isotopic compositions of DIC measured in rivers vary from-14.2‰to 3.5‰.At a first order,the DIC transported by rivers is derived from the chemical weathering’s consumption of CO_2 with a magmatic origin,enriched in^(13)C(-5%)and biogenic soil CO_2 with lower isotopic compositions.The highest δ^(13)C values likely result from C isotopes fractionation during CO_2 degassing in rivers.A mass balance based on carbon isotopes suggest that the contribution of magmatic CO_2 varied from less than 20%to more than 70%.Uncertainties in this calculation associated with CO_2 degassing in rivers are difficult to quantify,and the consequence of CO_2 degassing would be an overestimation of the contribution of DIC derived from the neutralization of magmatic CO_2 by silicate rocks. 展开更多
关键词 Carbon isotopes Dissolved inorganic carbon RIVERS Chemical weathering CHANGBAISHAN Active volcanic zone
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亮氨酸对黄牛皮下脂肪细胞棕色化的影响 被引量:2
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作者 郭逸芯 王之盛 +9 位作者 胡瑞 王俊梅 王森 施丽媛 张晓红 邹华围 左家学 彭全辉 薛白 王立志 《畜牧兽医学报》 CAS CSCD 北大核心 2023年第8期3286-3298,共13页
旨在分离黄牛皮下前体脂肪细胞,探究亮氨酸对白色脂肪细胞棕色化以及脂质代谢的影响。本研究采取4头3岁的健康雄性黄牛((351.7±42.5)kg)皮下脂肪组织分离前体脂肪细胞,混合后于细胞分化D 6-D 9添加不同浓度亮氨酸(0、0.5、1、2、4... 旨在分离黄牛皮下前体脂肪细胞,探究亮氨酸对白色脂肪细胞棕色化以及脂质代谢的影响。本研究采取4头3岁的健康雄性黄牛((351.7±42.5)kg)皮下脂肪组织分离前体脂肪细胞,混合后于细胞分化D 6-D 9添加不同浓度亮氨酸(0、0.5、1、2、4、8 mmol·L^(-1))(n=6)。RT-PCR检测棕色化标志基因,筛选亮氨酸诱导脂肪细胞棕色化的浓度,后续试验分为对照组(CON)和最佳浓度亮氨酸添加组(Leu)(n=6)。RT-PCR检测线粒体生物合成关键基因表达、mtDNA拷贝数以及脂质代谢相关基因的表达,Western Blot检测棕色化关键蛋白以及信号通路蛋白表达。Mito-tracker Green染色和油红O染色分别检测细胞内线粒体含量和脂滴形态的变化。结果表明,成功分离得到黄牛皮下前体脂肪细胞并诱导为成熟脂肪细胞。4 mmol·L^(-1)亮氨酸显著提高脂肪细胞中棕色化标志因子UCP1、PRDM 16和TMEM 26的mRNA相对表达量,线粒体生物合成关键基因SIRT1、TFAM和NRF 1/2的mRNA相对表达量,上调关键蛋白UCP1、CD137和SIRT1的表达量(P<0.01)。亮氨酸显著提高细胞中mtDNA拷贝数和线粒体含量(P<0.01),降低细胞内ATP含量(P<0.05),促使细胞脂滴由单房大脂滴向多房小脂滴转变,并降低细胞内甘油三酯的含量(P<0.01)。亮氨酸抑制脂肪合成基因ACC、FAS表达,促进脂肪分解基因ATGL、HSL和脂肪酸β氧化基因PPARα、CPT1、ACOX表达(P<0.01)。添加亮氨酸极显著上调p-AMPKα/AMPKα和PGC1α的蛋白表达量(P<0.01)。综上所述,亮氨酸能促进黄牛脂肪细胞棕色化和线粒体生物合成,促进脂肪分解抑制脂肪合成,减少细胞内脂质沉积,并上调p-AMPKα/AMPKα和PGC1α的蛋白表达量。 展开更多
关键词 亮氨酸 黄牛 原代脂肪细胞 棕色化 线粒体生物合成
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The therapeutic efficacy and safety of Gongxuening capsule in dysfunctional uterine bleeding:a systematic review and meta-analysis
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作者 xue bai Yan-Ru Zhang +1 位作者 Feng-Qin Zhang Hai-Zhu Zhang 《Medical Data Mining》 2020年第4期152-165,共14页
Background:Gongxuening capsule is a Chinese patent medicine for treating the dysfunctional uterine bleeding.We report a meta-analysis of the combination efficacy between conventional medicines with Chinese patent drug... Background:Gongxuening capsule is a Chinese patent medicine for treating the dysfunctional uterine bleeding.We report a meta-analysis of the combination efficacy between conventional medicines with Chinese patent drug Gongxuening in the treatment of dysfunctional uterine bleeding.Materials and methods:Seven databases were used to retrieve the relevant research of Chinese patent drug Gongxuening treatment for dysfunctional uterine bleeding from the databases establishment to 2020.The data were extracted independently by 2 researchers according to the described selection research.The meta-analysis was performed using RevMan5.3 software.Results:This study included 23 randomized trials,with a total of 1,836 dysfunctional uterine bleeding patients.Chinese patent drug Gongxuening could significantly improve the effective rate,and reduce endometrial thickness,control bleeding time,complete hemostasis time and sex hormone level,and no serious adverse events.Based on sensitivity analysis and subgroup analysis,the heterogeneity sources of endometrial thickness,complete hemostasis time and sex hormone level were found.In follicle stimulating hormone and luteinizing hormone,there was no significant difference between the two groups when Chinese patent drug Gongxuening combined with desogestrel ethinylestradiol.Conclusion:Conventional medicines combined with Chinese patent drug Gongxuening can make patients with dysfunctional uterine bleeding achieve better effective rate,and no serious adverse events occurred. 展开更多
关键词 Gongxuening capsule Conventional medicines Dysfunctional uterine bleeding META-ANALYSIS Systematic review
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包被复合微量元素对生长期云南半细毛羊生长性能、血清抗氧化及免疫指标的影响 被引量:3
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作者 任伊凡 薛白 +7 位作者 洪琼花 况应谷 周文艺 邵立圣 丁子悦 王之盛 王立志 彭全辉 《黑龙江畜牧兽医》 北大核心 2023年第11期98-105,共8页
为了研究不同添加水平的包被复合微量元素对生长期云南半细毛羊生长性能、血清抗氧化和免疫指标的影响,试验将健康的50只5月龄云南半细毛羊公羊根据体重随机分为5组,每组10只,对照组(Ⅰ组)饲喂基础日粮,试验组(Ⅱ、Ⅲ、Ⅳ、Ⅴ组)饲喂分... 为了研究不同添加水平的包被复合微量元素对生长期云南半细毛羊生长性能、血清抗氧化和免疫指标的影响,试验将健康的50只5月龄云南半细毛羊公羊根据体重随机分为5组,每组10只,对照组(Ⅰ组)饲喂基础日粮,试验组(Ⅱ、Ⅲ、Ⅳ、Ⅴ组)饲喂分别添加200,400,600,800 mg/kg包被复合微量元素的基础日粮,预试期10 d,正试期30 d。在试验第1,3天对试验羊空腹称重,计算干物质采食量(DMI)、平均日增重(ADG)、料重比(F/G);在试验第15,30天,每组随机选取5只羊采集血液分离血清,用于检测血清微量元素指标[铁(Fe)、铜(Cu)、锰(Mn)、锌(Zn)、硒(Se)、碘(I)和钴(Co)]、血清抗氧化指标[总超氧化物歧化酶(T-SOD)、过氧化氢酶(CAT)和丙二醛(MDA)]和血清免疫指标[免疫球蛋白A(IgA)、免疫球蛋白G(IgG)、免疫球蛋白M(IgM)、补体C3、补体C4及内毒素(ET)],对检测结果进行显著性分析、线性及二次效应分析。结果表明:各组间DMI差异不显著(P>0.05),ADG和F/G与包被复合微量元素添加水平呈二次关系(PQ<0.05),其中Ⅲ组ADG最高,F/G最低。在试验第30天,各组间绵羊血清Fe、Cu和Mn元素质量浓度差异不显著(P>0.05),血清Fe、Zn、Se、I和Co元素质量浓度随包被复合微量元素添加水平的增加呈线性升高(PL<0.05)。各组间绵羊血清T-SOD活性差异不显著(P>0.05);Ⅰ组血清CAT活性最低,Ⅱ、Ⅲ、Ⅳ组血清MDA浓度显著低于Ⅰ、Ⅴ组(P<0.05),且血清MDA浓度与包被复合微量元素添加水平呈二次关系(PQ<0.05),并随包被复合微量元素添加水平的增加呈线性升高(PL<0.05),其中Ⅲ组血清MDA浓度最低。绵羊血清IgA、补体C3和补体C4质量浓度及ET活性与包被复合微量元素添加水平既呈线性关系(PL<0.05)又呈二次关系(PQ<0.05),其中Ⅲ组IgA、IgG、IgM、补体C3、补体C4质量浓度最高;Ⅴ组ET活性最高,Ⅲ组最低。说明添加400 mg/kg包被复合微量元素能够提高绵羊的抗氧化能力和免疫性能,但是对绵羊生长性能影响不大,在本试验条件下,生长期云南半细毛羊饲料中包被复合微量元素以400 mg/kg的添加水平效果最佳,Fe、Cu、Mn、Zn、Se、I、Co添加水平分别为48.00,6.40,20.00,34.00,0.32,0.40,0.32 mg/kg。 展开更多
关键词 包被复合微量元素 绵羊 生长性能 抗氧化 免疫
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LPS对牦牛瘤胃上皮细胞补体C3激活和ATP生成代谢的影响 被引量:1
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作者 张祺琪 王俊梅 +9 位作者 岳子奇 郭逸芯 施丽媛 张晓红 邹华围 彭全辉 薛白 王立志 王之盛 胡瑞 《畜牧兽医学报》 CAS CSCD 北大核心 2023年第11期4664-4675,共12页
旨在通过脂多糖(LPS)诱导牦牛瘤胃上皮细胞建立炎症模型,考察瘤胃上皮细胞作为非免疫细胞是否存在细胞内补体C3激活,及其对细胞三磷酸腺苷(ATP)生成的影响,为瘤胃健康营养调控技术提供试验依据。用不同浓度的LPS处理牦牛瘤胃上皮细胞系... 旨在通过脂多糖(LPS)诱导牦牛瘤胃上皮细胞建立炎症模型,考察瘤胃上皮细胞作为非免疫细胞是否存在细胞内补体C3激活,及其对细胞三磷酸腺苷(ATP)生成的影响,为瘤胃健康营养调控技术提供试验依据。用不同浓度的LPS处理牦牛瘤胃上皮细胞系,采用CCK-8法测定细胞活力;ELISA试剂盒测定细胞内补体C3激活产物C3a、C3b浓度以及培养基中白细胞介素-1β(IL-1β)、白细胞介素-6(IL-6)、肿瘤坏死因子α(TNF-α)浓度;化学法检测细胞内ATP浓度,线粒体红色荧光探针和流式细胞仪检测线粒体数量及膜电位;qPCR检测细胞IL-1β、IL-6、TNF-α,补体C3及其激活关键酶组织蛋白酶B(CTSB)和组织蛋白酶L(CTSL),以及ATP合成酶亚基(ATP 5A和ATP 5C1)等基因相对表达量。结果发现:1)不同浓度LPS处理后,牦牛瘤胃上皮细胞活力极显著下调(P<0.01),TNF-α、IL-1β和IL-6等促炎因子的基因表达量和浓度极显著上调(P<0.01),在LPS浓度为10μg·mL^(-1)时,牦牛瘤胃上皮细胞炎症模型构建成功;2)炎症下,牦牛瘤胃上皮细胞内补体C3及其激活关键酶CTSB的基因表达量极显著升高(P<0.01),激活产物补体片段C3a和C3b浓度极显著升高(P<0.01);3)炎症下,牦牛瘤胃上皮细胞ATP含量极显著下降(P<0.01),线粒体膜电位显著降低(P<0.05),ATP合成酶亚基ATP 5A和ATP 5C1的基因表达量随着LPS处理浓度升高显著下调(P<0.01)。综上,利用LPS诱导建立了牦牛瘤胃上皮细胞炎症模型。在LPS刺激下,牦牛瘤胃上皮细胞可发生细胞内补体C3激活过程,并抑制线粒体ATP合成酶亚基ATP 5A、ATP 5C1和有氧呼吸关键酶ME 1的基因表达,线粒体膜电位降低,抑制ATP生成。因此,LPS诱导炎症可抑制瘤胃上皮细胞ATP生成,从而导致瘤胃健康问题。 展开更多
关键词 牦牛 瘤胃上皮细胞 免疫炎症 补体C3 ATP
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用于氧还原反应的双原子钴-铁催化剂 被引量:1
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作者 唐甜蜜 王寅 +5 位作者 韩憬怡 张巧巧 白雪 牛效迪 王振旅 管景奇 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2023年第3期48-55,共8页
金属-空气电池因其高效率和便携性受到广泛关注.然而,氧还原反应(ORR)的高能垒和缓慢的动力学导致其输出功率低.尽管贵金属铂基材料具有较高的ORR活性,但其在工业上的大规模应用受到高成本的制约.因此,迫切需要以储量丰富的非贵金属为原... 金属-空气电池因其高效率和便携性受到广泛关注.然而,氧还原反应(ORR)的高能垒和缓慢的动力学导致其输出功率低.尽管贵金属铂基材料具有较高的ORR活性,但其在工业上的大规模应用受到高成本的制约.因此,迫切需要以储量丰富的非贵金属为原料,开发具有低成本、高性能和耐用性的催化剂.近年来,单原子过渡金属与氮共掺杂碳材料(M-N-C)成为替代贵金属催化剂的理想材料.理论模拟和实验结果均表明,单原子Fe/Co-N-C催化剂具有良好的ORR活性,其中FeN_(4)和CoN_(4)构型被认为是主要活性位点.此外,含有相邻金属位点的双金属单原子催化剂具有加速ORR动力学的巨大潜力.通过对ORR中间体的桥式-顺式吸附,双金属位点可以促进O-O键的裂解,从而提高催化活性.除固有活性外,双金属位点可减少ORR过程中含氧中间体对M-N键的攻击,提高M-N-C对ORR的耐久性和工业应用潜力.因此,近年来,研究者开始探索双金属单原子催化剂的合成和电催化性能,发现Fe-Co, Fe-Mn, Fe-Cu, Co-Zn和Co-Pt双位点可以有效催化ORR.为进一步提高ORR活性,需要合理调节双原子结构,并引入更多的双金属位点.本文在氮掺杂石墨烯纳米片上构建了一种含FeN_(3)-CoN_(3)位点的新型双原子催化剂(CoFe-NG),该催化剂具有较好的ORR催化活性,半波电位为0.917 V, Tafel斜率为46 mV dec^(-1),远远优于单原子Fe-NG、单原子Co-NG和Pt/C催化剂.Koutecky-Levich曲线和H_(2)O_(2)产率揭示了CoFe-NG具有高效的四电子ORR过程,不仅表现出高电流密度,而且对氧还原为OH-(而不是过氧化氢)更具选择性.计时安培测试结果表明, CoFe-NG对甲醇和一氧化碳中毒具有较高的耐受性.KSCN中毒实验结果表明, SCN^(-)离子与Fe和Co位点发生强配位作用并使活性位点中毒.以CoFe-NG为空气电极组装的锌-空气电池,开路电压为1.47 V,峰值功率密度高达230 mW cm^(-2),具有良好的充放电循环稳定性,可以为一个小灯泡供电,并且在5 mA cm^(-2)条件下持续充放电250 h,输出电压几乎不变.理论计算表明,掺氮石墨烯上的FeN_(3)-CoN_(3)位点比FeN_(4)和CoN_(4)位点具有更低的ORR能垒, FeN_(3)-CoN_(3)位点上的速控步是^(*)OH中间体向H_(2)O的转化,与单位点FeN_(4)和CoN_(4)不同.综上,本文为可控合成高性能双金属单原子催化剂及进一步深入分析其电催化氧还原反应机理提供参考. 展开更多
关键词 双原子催化剂 M-N-C 氧还原反应 理论计算 锌-空气电池
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3D打印尼龙1212的无氧老化机理 被引量:1
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作者 郭荣哲 薛白 +1 位作者 谢兰 梁寅 《塑料工业》 CAS CSCD 北大核心 2023年第6期115-121,共7页
尼龙材料是3D打印的主要材料之一,其老化行为大大降低了循环使用率,造成材料的浪费。为了深入了解3D打印过程中尼龙粉末的变化情况,以尼龙1212(PA1212)粉末为原料,通过人工加速烧结模拟实验,以不同老化时间的粉末为研究对象,采用理论与... 尼龙材料是3D打印的主要材料之一,其老化行为大大降低了循环使用率,造成材料的浪费。为了深入了解3D打印过程中尼龙粉末的变化情况,以尼龙1212(PA1212)粉末为原料,通过人工加速烧结模拟实验,以不同老化时间的粉末为研究对象,采用理论与分析相结合的方式,探究尼龙无氧热老化机理。通过扫描电子显微镜(SEM)、X射线光电子能谱(XPS)、凝胶渗透色谱(GPC)、傅里叶红外光谱(FTIR)等测试,分析3D打印过程中粉料的无氧热老化行为。粉末吸收热量,导致球形尺寸增大,表面缺陷突增,黏度增加等。尼龙材料的无氧热老化过程伴随复杂的重排交联反应,酰胺键的C=O双键损耗,分子间作用力减弱,导致熔融和结晶等发生偏移,半结晶材料的尼龙结晶能力下降。此研究为尼龙材料在3D打印领域的发展提供了理论基础。 展开更多
关键词 尼龙1212 无氧老化 选择性激光烧结
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