期刊文献+
共找到906篇文章
< 1 2 46 >
每页显示 20 50 100
Weak electric field promotes anaerobic granular sludge formation to enhance medium-chain fatty acids synthesis
1
作者 Wei-Tong Ren Tian Lan +5 位作者 Zi-Lin He Hua-Zhe Wang Lin Deng Shan-Shan Ye Qing-Lian Wu Wan-Qian Guo 《Chinese Chemical Letters》 2025年第8期632-635,共4页
Granular sludges can resist the toxicity inhibition of medium-chain fatty acids(MCFAs)and enhance the chain elongation(CE)process.However,the granulation process is time-consuming and requires a suitable facilitating ... Granular sludges can resist the toxicity inhibition of medium-chain fatty acids(MCFAs)and enhance the chain elongation(CE)process.However,the granulation process is time-consuming and requires a suitable facilitating granulation mean.This study proposed two continuous fed Expanded Granular Sludge Bed bioreactors,one with electric field(EF)and one without,to demonstrate the promotion of sludge granulation by EF and the enhancement of MCFAs production efficiency by the anaerobic granular sludge(An GS).Through more than 50 days of operation,the EF was demonstrated to be able to promote the granulation,and the formed An GS enhanced MCFAs yield by 36%.Besides,mechanism analysis indicated that the EF promoted microbial aggregation and extracellular polymeric substances(EPS)synthesis,which enabled An GS to form more easily.Besides,An GS formed with EF improved extracellular electron transfer capacity and microbial function activity,which also contributed to the production of more MCFAs.Overall,this study provides a method to facilitate An GS granulation and revealed the underlying mechanisms,and offers important support for the diverse applications of An GS in other bioresources recovery bioprocesses. 展开更多
关键词 Chain elongation medium-chain fatty acids Electric field Anaerobic granular sludge Microbial functions
原文传递
Efficacy of medium-chain fatty acid salts distilled from coconut oil against two enteric pathogen challenges in weanling piglets 被引量:8
2
作者 Paola López-Colom Lorena Castillejos +3 位作者 Agustina Rodríguez-Sorrento Mónica Puyalto Juan JoséMallo Susana María Martín-Orúe 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2020年第1期251-267,共17页
Background:The search for alternatives to antibiotics in pig production has increased the interest in natural resources with antimicrobial properties,such as medium-chain fatty acids(MCFA)as in-feed additives.This stu... Background:The search for alternatives to antibiotics in pig production has increased the interest in natural resources with antimicrobial properties,such as medium-chain fatty acids(MCFA)as in-feed additives.This study evaluated the potential of a novel blend of MCFA salts(DIC)from distilled coconut oil with a lauric acid content to reduce enteropathogens and control intestinal diseases around weaning.Two experimental disease models were implemented in early-weaned piglets,consisting of two oral challenges:Salmonella Typhimurium(1.2×10~8 CFU)or enterotoxigenic Escherichia coli(ETEC)F4(1.5×10~9 CFU).The parameters assessed were:animal performance,clinical signs,pathogen excretion,intestinal fermentation,immune-inflammatory response,and intestinal morphology.Results:The Salmonella challenge promoted an acute course of diarrhea,with most of the parameters responding to the challenge,whereas the ETEC F4 challenge promoted a mild clinical course.A consistent antipathogenic effect of DIC was observed in both trials in the hindgut,with reductions in Salmonella spp.plate counts in the cecum(P=0.03)on d 8 post-inoculation(PI)(Salmonella trial),and of enterobacteria and total coliform counts in the ileum and colon(P<0.10)on d 8 PI(ETEC F4 trial).When analyzing the entire colonic microbiota(16 S rRNA gene sequencing),this additive tended(P=0.13)to reduce the Firmicutes/Bacteroidetes ratio and enriched Fibrobacteres after the Salmonella challenge.In the ETEC F4 challenge,DIC prompted structural changes in the ecosystem with increases in Dialister,and a trend(P=0.14)to increase the Veillonellaceae family.Other parameters such as the intestinal fermentation products or serum pro-inflammatory mediators were not modified by DIC supplementation,nor were the histological parameters.Only the intraepithelial lymphocyte(IEL)counts were lowered by DIC in animals challenged with Salmonella(P=0.07).With ETEC F4,the IEL counts were higher with DIC on d 8 PI(P=0.08).Conclusions:This study confirms the potential activity of this MCFA salts mixture to reduce intestinal colonization by opportunistic pathogens such as Salmonella or E.coli and its ability to modulate colonic microbiota.These changes could explain to some extent the local immune cell response at the ileal level. 展开更多
关键词 ENTERIC PATHOGEN Gut microbiota Intestinal immunity medium-chain fatty acids WEANING pig
在线阅读 下载PDF
Medium-chain fatty acids and monoglycerides as feed additives for pig production:towards gut health improvement and feed pathogen mitigation 被引量:24
3
作者 Joshua A.Jackman RDean Boyd Charles C.Elrod 《Journal of Animal Science and Biotechnology》 CAS CSCD 2020年第3期611-625,共15页
Ongoing challenges in the swine industry,such as reduced access to antibiotics and virus outbreaks(e.g.,porcine epidemic diarrhea virus,African swine fever virus),have prompted calls for innovative feed additives to s... Ongoing challenges in the swine industry,such as reduced access to antibiotics and virus outbreaks(e.g.,porcine epidemic diarrhea virus,African swine fever virus),have prompted calls for innovative feed additives to support pig production.Medium-chain fatty acids(MCFAs)and monoglycerides have emerged as a potential option due to key molecular features and versatile functions,including inhibitory activity against viral and bacterial pathogens.In this review,we summarize recent studies examining the potential of MCFAs and monoglycerides as feed additives to improve pig gut health and to mitigate feed pathogens.The molecular properties and biological functions of MCFAs and monoglycerides are first introduced along with an overview of intervention needs at different stages of pig production.The latest progress in testing MCFAs and monoglycerides as feed additives in pig diets is then presented,and their effects on a wide range of production issues,such as growth performance,pathogenic infections,and gut health,are covered.The utilization of MCFAs and monoglycerides together with other feed additives such as organic acids and probiotics is also described,along with advances in molecular encapsulation and delivery strategies.Finally,we discuss how MCFAs and monoglycerides demonstrate potential for feed pathogen mitigation to curb disease transmission.Looking forward,we envision that MCFAs and monoglycerides may become an important class of feed additives in pig production for gut health improvement and feed pathogen mitigation. 展开更多
关键词 ANTIBIOTICS Feed pathogen mitigation Growth promotion Gut health Immune enhancement MCFA medium-chain fatty acids MONOGLYCERIDES
在线阅读 下载PDF
Medium-Chain Triglyceride Activated Brown Adipose Tissue and Induced Reduction of Fat Mass in C57BL/6J Mice Fed High-fat Diet 被引量:11
4
作者 ZHANG Yong XU Qing +7 位作者 LIU Ying Hua ZHANG Xin Sheng WANG Jin YU Xiao Ming ZHANG Rong Xin XUE Chao YANG Xue Yan XUE Chang Yong 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2015年第2期97-104,共8页
Objective To investigate activation of brown adipose tissue (BAT) stimulated by medium-chain triglyceride (MCT). Methods 30 Male C57BL/6J obese mice induced by fed high fat diet (HFD) were divided into 2 groups,... Objective To investigate activation of brown adipose tissue (BAT) stimulated by medium-chain triglyceride (MCT). Methods 30 Male C57BL/6J obese mice induced by fed high fat diet (HFD) were divided into 2 groups, and fed another HFD with 2% MCT or long-chain triglyceride (LCT) respectively for 12 weeks. Body weight, blood biochemical variables, interscapular brown fat tissue (IBAT) mass, expressions of mRNA and protein of beta 3-adrenergic receptors (β3-AR), uncoupling protein-1 (UCP1), hormone sensitive lipase (HSL), protein kinase A (PKA), and adipose triglyceride lipase (ATGL) in IBAT were measured. Results Significant decrease in body weight and body fat mass was observed in MCT group as compared with LCT group (P〈O.05) after 12 weeks. Greater increases in IBAT mass was observed in MCT group than in LCT group (P〈O.05). Blood TG, TC, LDL-C in MCT group were decreased significantly, meanwhile blood HDL-C, ratio of HDL-C/LDL-C and norepinephrine were increased markedly. Expressions of mRNA and protein of β3-AR, UCP1, PKA, HSL, ATGL in BAT were greater in MCT group than in LCT group (P〈O.05). Conclusion Our results suggest that MCT stimulated the activation of BAT, possible via norepinephrine pathway, which might partially contribute to reduction of the body fat mass in obese mice fed high fat diet. 展开更多
关键词 medium-chain triglyceride Brown adipose tissue Uncoupling protein-l Beta 3-adrenergicreceptor
暂未订购
Inhibition of African swine fever virus in liquid and feed by medium-chain fatty acids and glycerol monolaurate 被引量:6
5
作者 Joshua A.Jackman Astghik Hakobyan +1 位作者 Hovakim Zakaryan Charles C.Elrod 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2021年第2期569-578,共10页
Background:The ongoing African swine fever virus(ASFv)epidemic has had a major impact on pig production globally and biosecurity efforts to curb ASFv infectivity and transmission are a high priority.It has been recent... Background:The ongoing African swine fever virus(ASFv)epidemic has had a major impact on pig production globally and biosecurity efforts to curb ASFv infectivity and transmission are a high priority.It has been recently identified that feed and feed ingredients,along with drinking water,can serve as transmission vehicles and might facilitate transboundary spread of ASFv.Thus,it is important to test the antiviral activity of regulatory compatible,antiviral feed additives that might inhibit ASFv infectivity in feed.One promising group of feed additive candidates includes medium-chain fatty acids(MCFA)and monoglyceride derivatives,which are known to disrupt the lipid membrane surrounding certain enveloped viruses and bacteria.Results:The antiviral activities of selected MCFA,namely caprylic,capric,and lauric acids,and a related monoglyceride,glycerol monolaurate(GML),to inhibit ASFv in liquid and feed conditions were investigated and suitable compounds and inclusion rates were identified that might be useful for mitigating ASFv in feed environments.Antiviral assays showed that all tested MCFA and GML inhibit ASFv.GML was more potent than MCFA because it worked at a lower concentration and inhibited ASFv due to direct virucidal activity along with one or more other antiviral mechanisms.Dose-dependent feed experiments further showed that sufficiently high GML doses can significantly reduce ASFv infectivity in feed in a linear manner in periods as short as 30 min,as determined by infectious viral titer measurements.Enzyme-linked immunosorbent assay(ELISA)experiments revealed that GML treatment also hinders antibody recognition of the membrane-associated ASFv p72 structural protein,which likely relates to protein conformational changes arising from viral membrane disruption.Conclusion:Together,the findings in this study indicate that MCFA and GML inhibit ASFv in liquid conditions and that GML is also able to reduce ASFv infectivity in feed,which may help to curb disease transmission. 展开更多
关键词 African swine fever virus ANTIVIRAL Feed pathogen mitigation MCFA medium-chain fatty acids MONOGLYCERIDES
在线阅读 下载PDF
Lipase Catalyzed Synthesis of Medium-chain Biodiesel from Cinnamonum camphora Seed Oil 被引量:1
6
作者 刘军锋 邓利 +4 位作者 王萌 聂开立 刘珞 谭天伟 王芳 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第Z1期1215-1219,共5页
The non-edible camphor tree seed oil was extracted and catalyzed by immobilized lipase for biodiesel production. The oil yield from camphor tree seeds reached 35.2% of seed weight by twice microwave-assisted extractio... The non-edible camphor tree seed oil was extracted and catalyzed by immobilized lipase for biodiesel production. The oil yield from camphor tree seeds reached 35.2% of seed weight by twice microwave-assisted extractions. Gas chromatography showed that free fatty acid content in camphor tree seed oil was 1.88%, and the main fatty acids were capric acid(53.4%) and lauric acid(38.7%). With immobilized lipase Candida sp. 99–125as catalyst, several important factors for reaction conditions were examined through orthogonal experiments.The optimum conditions were obtained: water content and enzyme loading were both 15% with a molar ratio of 1:3.5(oil/ethanol), and the process of alcoholysis was in nine steps at 40 °C for 24 h, with agitation at170 r·min-1. As a result, the medium-chain biodiesel yield was 93.5%. The immobilized lipase was stable when it was used repeatedly for 210 h. 展开更多
关键词 CAMPHOR tree seed oil medium-chain BIODIESEL LIPASE ETHANOLYSIS
在线阅读 下载PDF
Anti-Obesity Effects of Dietary d-Allulose and Medium-Chain Triglycerides in High-Fat Diet-Fed Rats
7
作者 Tatsuhiro Matsuo Chihiro Yokoyama +4 位作者 Takako Yamada Tetsuo Iida Susumu Mochizuki Akihide Yoshihara Kazuya Akimitsu 《Food and Nutrition Sciences》 CAS 2024年第8期701-710,共10页
d-Allulose, a rare sugar, exerts anti-obesity effects by inhibiting hepatic lipogenesis and promoting energy expenditure. Medium-chain triglycerides (MCTs) consist of three medium-chain fatty acids connected by glycer... d-Allulose, a rare sugar, exerts anti-obesity effects by inhibiting hepatic lipogenesis and promoting energy expenditure. Medium-chain triglycerides (MCTs) consist of three medium-chain fatty acids connected by glycerol. MCTs have been extensively investigated for their ability to reduce body fat accumulation. We previously investigated the anti-obesity effects of a combination of dietary d-allulose and MCT (5% - 13%) in rats;however, we could not confirm the anti-obesity effects of MCT or observed synergetic effects between d-allulose and MCT on body fat loss. We speculated that our previous studies were influenced by the excessive amount of MCT in the diets. Therefore, in this study, we aimed to investigate the anti-obesity effects of the simultaneous intake of d-allulose and MCT in rats fed an obesity-inducing high-fat diet with a low amount of MCTs (2%). Thirty-two male Wistar rats (3-week-old) were randomly divided into four groups: control, d-allulose, MCT, and d-allulose + MCT groups. Rats in each group were fed ad libitum on a control (no d-Allulose or MCT), 5% d-allulose, 2% MCT, or 5% d-allulose + 2% MCT diets for 16 weeks. Abdominal adipose tissue weights were significantly lower in the d-allulose diet group than in the control group, whereas no differences were observed between results of the MCT-supplemented groups. The total body fat mass was significantly lower in the d-allulose and MCT diet groups than in the control group, but no differences were observed between the MCT-supplemented groups. These results suggested that anti-obesity effects of dietary d-allulose were observed, and the effects of dietary MCTs were weaker than those of d-allulose. Moreover, we confirmed the interaction between dietary d-allulose and MCT on indicators of obesity. Interestingly, their effects were not synergistic, as MCT supplementation offset the anti-obesity effects of dietary d-allulose. However, the specific mechanisms underlying those effects remain unknown, warranting further investigation. 展开更多
关键词 Rare Sugar d-Allulose medium-chain Triglycerides Body Fat RAT
暂未订购
Transcriptome analysis revealed the molecular mechanism of increasing the yield of medium-chain fatty acid ethyl esters through redox potential regulation driven by hydrogen peroxide during simulated wine alcoholic fermentation
8
作者 Huan-Huan Yu Zi-Xuan Nie +4 位作者 Xiao-Min Wang Jia-Liang Hu Lu Wang Hong-Yan Zhang Guo-Jie Jin 《Food Bioscience》 2025年第6期2694-2703,共10页
The medium-chain fatty acid ethyl esters(MCFAEEs)are extremely important for the aroma profile of wines,and their metabolism process is influenced by the oxidation–reduction potential(ORP).However,the molecular mecha... The medium-chain fatty acid ethyl esters(MCFAEEs)are extremely important for the aroma profile of wines,and their metabolism process is influenced by the oxidation–reduction potential(ORP).However,the molecular mechanism by which ORP regulates MCFAEE production remains unclear.This study investigated these mechanisms based on transcriptome analysis of Saccharomyces cerevisiae under different ORPs during various stages of wine alcohol fermentation.The results showed that ORP regulation significantly changed the expression of genes involved in MCFAEE synthesis metabolic pathway.The expression level of pyruvate decarboxylase gene PDC6 was upregulated by 1.89-fold and 2.2-fold at 0 mV compared to􀀀100 mV during the early and middle fermentation stages,respectively.Similarly,aldehyde dehydrogenase gene ALD6 was upregulated by 1.8-fold at 0 mV relative to 60 mV in the late stage.Additionally,several genes involved in cell cycle,glutathione metabolism,the pentose phosphate pathway and MAPK signaling pathway,exhibited higher expression at 0 mV when compared to􀀀100 and 60 mV,which maybe thereby promote MCFAEE metabolism.These results establish a theoretical foundation for future research on the ORP regulation to improve the aroma quality of wines and provide a reference for the application of ORP operation in wine production. 展开更多
关键词 Oxidation-reduction potential medium-chain fatty acid ethyl ester Transcriptomic Wine alcohol fermentation Molecular mechanism
原文传递
高产酯化酶霉菌的筛选、鉴定及产酶条件优化
9
作者 王琳 芦羿涛 +4 位作者 彭粲 吴华星 林东 帖余 张文学 《中国调味品》 北大核心 2026年第3期85-89,共5页
短中链脂肪酸乙酯作为传统发酵食品(如白酒、食醋等)的关键风味物质,其含量对产品的香气特征与品质等级具有重要影响。该实验将从大曲中筛选到的高产酯化酶的霉菌命名为F5,并通过形态观察和分子生物学鉴定霉菌F5为小孢根霉(Rhizopus mic... 短中链脂肪酸乙酯作为传统发酵食品(如白酒、食醋等)的关键风味物质,其含量对产品的香气特征与品质等级具有重要影响。该实验将从大曲中筛选到的高产酯化酶的霉菌命名为F5,并通过形态观察和分子生物学鉴定霉菌F5为小孢根霉(Rhizopus microsporus),该菌具有广泛的生长温度适应性和高温生长偏好性,能够较好地适应不同的发酵酿造环境。通过单因素实验和正交实验优化发酵麸曲产酶条件,确定初始接种量为9%、初始水分含量为50%、发酵温度为45℃、发酵时间为5 d时,小孢根霉产酯化酶酶活达到2.76 U。该研究为中国传统发酵食品中短中链脂肪酸乙酯含量的提升提供了优质的菌株资源,具有较好的实践应用价值。 展开更多
关键词 小孢根霉 酯化酶 短中链脂肪酸乙酯 产酶条件优化
在线阅读 下载PDF
生物印迹脂肪酶催化合成ARA型中长链甘油三酯的研究
10
作者 邹孝强 张康 +5 位作者 胡纪洁 潘月超 刘文雪 郭修圣 张羽飞 郑明明 《食品与发酵工业》 北大核心 2026年第5期44-51,66,共9页
花生四烯酸(arachidonic acid,ARA)可直接参与婴幼儿认知和视觉功能的构建,以中长链甘油三酯(medium-and long-chain triglycerides,MLCT)为载体制备ARA型的结构脂质可提升婴幼儿对ARA的吸收效率。该研究以表面活性剂生物印迹脂肪酶提... 花生四烯酸(arachidonic acid,ARA)可直接参与婴幼儿认知和视觉功能的构建,以中长链甘油三酯(medium-and long-chain triglycerides,MLCT)为载体制备ARA型的结构脂质可提升婴幼儿对ARA的吸收效率。该研究以表面活性剂生物印迹脂肪酶提升酶活力,并催化裂殖壶菌微生物油与中链甘油三酯(medium-chain triglycerides,MCT)的酯交换反应合成ARA型MLCT。通过单因素试验和正交试验确定生物印迹脂肪酶的最佳制备条件如下:以Lipozyme 435为催化剂,吐温-20为生物印迹模板,表面活性剂质量浓度为50 mg/L,缓冲液pH值为7.0,这使得印迹后脂肪酶的初始活力比印迹前提高了1.36倍。MLCT合成的最佳条件为脂肪酶添加量的质量分数为6%、MCT与微生物油摩尔比1.5∶1、温度70℃、反应时间6 h,产物组成的质量分数为13.12%MCT、66.80%MLCT和20.08%长链甘油三酯(long-chain triglycerides,LCT)。其中,位于sn-1,3位的MCFA的摩尔分数为58.13%,位于sn-2位的ARA摩尔分数为15.61%。生物印迹脂肪酶重复使用7次后MLCT含量仍保持61.05%。该研究合成ARA型MLCT,提高了ARA生物利用率,在功能食品和营养保健品中具有潜在应用价值。 展开更多
关键词 生物印迹 酯交换 中长链甘油三酯 花生四烯酸 正交试验
在线阅读 下载PDF
强化企业主体地位推进建设制造强国
11
作者 钟志华 黄庆学 +4 位作者 朱明皓 邵立国 臧冀原 焦伊景 路守望 《中国工程科学》 北大核心 2026年第1期106-116,共11页
企业是市场经济的和科技创新的主体、推动制造业高质量发展的关键载体,先进制造业集群是企业集聚和协同发展的产业生态系统,强化企业主体地位、培育世界级先进制造业集群是推进制造强国建设的关键支撑。本文从龙头企业、中小企业、先进... 企业是市场经济的和科技创新的主体、推动制造业高质量发展的关键载体,先进制造业集群是企业集聚和协同发展的产业生态系统,强化企业主体地位、培育世界级先进制造业集群是推进制造强国建设的关键支撑。本文从龙头企业、中小企业、先进制造业集群3个层面出发,对以企业为主体推进制造强国建设的主要成就进行了系统梳理与分析,并讨论了领军企业、中小企业和世界级先进制造业集群的发展重点任务。在制造强国建设进程中,企业体系整体实力持续提升:制造业龙头企业规模实力、国际市场竞争力显著提升,在关键核心技术攻关、产业链组织中发挥了引领作用;中小企业梯度培育体系逐步完善,以专精特新“小巨人”、制造业“单项冠军”为代表的中小企业在细分领域和关键环节的专业化能力明显增强;国家先进制造业集群、中小企业特色产业集群加快布局,成为承载制造业高质量发展的重要空间载体。面向未来,应集中要素资源支持企业主体能力建设,培育具有国际产业链控制力的领军企业,推动大中小企业融通发展,加快中小企业数字化转型和“人工智能+”应用场景培育,持续提升国家先进制造业集群竞争力,为制造强国建设筑牢坚实的微观基础和中观支撑。 展开更多
关键词 制造强国 主体地位 领军企业 中小企业 先进制造业集群 产业链协同
在线阅读 下载PDF
Effect of medium-chain triglycerides on growth performance, nutrient digestibility,plasma metabolites and antioxidant capacity in weanling pigs 被引量:16
12
作者 Yue Li Hao Zhang +2 位作者 Li Yang Lili Zhang Tian Wang 《Animal Nutrition》 SCIE 2015年第1期12-18,共7页
The aim of this study was to investigate the effect of medium-chain triglycerides(MCTs) on growth performance, nutrient digestibility, plasma metabolites and antioxidant capacity in weanling pigs. A total of 160 weanl... The aim of this study was to investigate the effect of medium-chain triglycerides(MCTs) on growth performance, nutrient digestibility, plasma metabolites and antioxidant capacity in weanling pigs. A total of 160 weanling(Duroc × Landrace x Yorkshire) pigs(age: 21 ± 1 d; body weight: 7.50 ± 0.28 kg) were randomly allotted to 4 treatments, receiving the following diets for 28 d: control diet [containing 3.5%soybean oil(SO)], MCT1 diet(containing 0.7% MCTs and 2.8% SO), MCT2 diet(containing 1.4% MCTs and2.1% SO) and MCT3 diet(containing 2.1% MCTs and 1.4% SO). Dietary inclusion of MCTs improved the average daily gain and feed efficiency(FE) of pigs compared with the control during the first 2 weeks post-weaning(P < 0.05). A similar positive effect was also observed for the overall FE in MCT2 group(P < 0.05). Compared with the control, apparent total tract digestibility(ATTD) of ether extract was improved by MCT2 and MCT3 treatment from day 12-14 post-weaning(P < 0.05). In addition, MCT2 treatment also exerted a beneficial effect on the ATTD of dry matter(P < 0.05). The increased total protein concentration and decreased urea nitrogen and malondialdehyde levels of plasma were observed in both MCT2 and MCT3 groups on day 14 post-weaning(P < 0.05). In conclusion, MCTs could improve growth performance, nutrients utilization, and antioxidant ability of weanling piglets. 展开更多
关键词 medium-chain TRIGLYCERIDES Growth performance NUTRIENT DIGESTIBILITY Metabolites Lipid PEROXIDATION PIGLETS
原文传递
嵌入核心企业供应链网络对“专精特新”中小企业创新能力的影响研究
13
作者 王鹏 肖晋 《工业技术经济》 北大核心 2026年第1期12-22,共11页
“专精特新”中小企业在提高我国产业链供应链韧性,推动产业链供应链现代化发展方面发挥着重要作用。从供应链溢出视角出发,以2014~2024年A股上市“专精特新”中小企业作为研究对象,通过匹配企业上下游供应商和客户数据,实证考察了沿核... “专精特新”中小企业在提高我国产业链供应链韧性,推动产业链供应链现代化发展方面发挥着重要作用。从供应链溢出视角出发,以2014~2024年A股上市“专精特新”中小企业作为研究对象,通过匹配企业上下游供应商和客户数据,实证考察了沿核心企业供应链溢出效应对“专精特新”中小企业创新能力的影响及其作用机制。研究发现,嵌入核心企业供应链网络显著提升了“专精特新”中小企业创新能力;从影响机制来看,沿核心企业供应链网络的知识溢出效应对“专精特新”企业创新能力具有双重影响,在促进企业创新深度的同时也限制了创新宽度。而规模效应机制主要发挥正向赋能作用;进一步研究发现,当“专精特新”中小企业具有更高的人力资本、为非国有控股企业以及属于技术资本密集型行业时,核心企业供应链对中小企业的创新溢出效应更显著。 展开更多
关键词 “专精特新”中小企业 供应链网络 技术创新 溢出效应 上下游企业 产业链供应链韧性 创新投入 市场交易成本
在线阅读 下载PDF
中链脂肪酸对家禽生产性能及肠道健康的影响
14
作者 刘瑾 侯飞雪 +6 位作者 张翠珍 朱懿可 暴雨婷 刘文静 黎观红 龙吉云 周华 《中国家禽》 北大核心 2026年第1期112-118,共7页
在绿色可持续发展目标驱动下,家禽养殖业正面临提质增效与生态友好的双重诉求。中链脂肪酸(MCFAs)作为新型功能性添加剂,凭借其独特的营养代谢特性和生理调节功能,为替代抗生素提供创新解决方案。文章系统阐述MCFAs通过快速供能机制提... 在绿色可持续发展目标驱动下,家禽养殖业正面临提质增效与生态友好的双重诉求。中链脂肪酸(MCFAs)作为新型功能性添加剂,凭借其独特的营养代谢特性和生理调节功能,为替代抗生素提供创新解决方案。文章系统阐述MCFAs通过快速供能机制提升饲料利用率、调节脂质代谢,降低腹脂沉积、维持肠道菌群稳态,增强抗菌屏障以及激活免疫调节通路等多重作用路径,综合论证其对家禽生产效能和肠道健康的提升效果,为构建环境友好型家禽养殖体系提供理论支撑与实践参考。 展开更多
关键词 中链脂肪酸 生产性能 肠道健康 家禽
原文传递
日粮添加中链脂肪酸对母猪繁殖性能、粪便菌群及哺乳仔猪生长性能的影响
15
作者 宁帅 张相雷 +2 位作者 金灵红 杨金玉 钟翔 《南京农业大学学报》 北大核心 2026年第2期403-415,共13页
[目的]本试验旨在探究日粮中补充中链脂肪酸(medium-chain fatty acids,MCFA)对母猪繁殖性能、粪便菌群以及哺乳仔猪生长性能的影响。[方法]选用体重和胎次接近、妊娠85 d“长×大”健康母猪32头,随机分成2组,每组16个(头)重复。对... [目的]本试验旨在探究日粮中补充中链脂肪酸(medium-chain fatty acids,MCFA)对母猪繁殖性能、粪便菌群以及哺乳仔猪生长性能的影响。[方法]选用体重和胎次接近、妊娠85 d“长×大”健康母猪32头,随机分成2组,每组16个(头)重复。对照组(Con)饲喂基础日粮,试验组在基础日粮中补充0.1%MCFA。试验期从母猪妊娠85 d到仔猪哺乳21 d,分娩当日记录母猪每窝产仔数、死胎数、弱仔数、仔猪出生个体重,采集初乳、妊娠110 d和哺乳21 d母猪血清用于分析;哺乳21 d直肠取样法采集母猪新鲜粪便用于微生物高通量测序分析;哺乳21 d测量仔猪体重,采集血样用于分析。[结果]与对照组相比,MCFA组后代仔猪出生体重显著提高(P<0.05),出生窝重显著提高(P<0.05);妊娠期日粮补充MCFA使母猪初乳中的乳脂含量显著提高(P<0.05),免疫球蛋白A(IgA)含量增加13.53%(P=0.087),IgG含量显著提高8.98%(P<0.05),IgM含量极显著提高19.85%(P<0.001)。妊娠110 d,MCFA组母猪血清总超氧化物歧化酶(T-SOD)活性显著提高(P<0.05),血清丙二醛(MDA)含量显著低于对照组(P<0.05)。哺乳21 d,MCFA组母猪血清催乳素含量相较于对照组显著提高(P<0.05)。母猪粪便菌群测序结果显示,MCFA组母猪ACE指数显著提高(P<0.05),肠道拟杆菌门的相对丰度显著提高(P<0.05),肠道纤维杆菌门的相对丰度显著提高(P<0.05),猪肠道中纤维杆菌属的相对丰度显著增加(P<0.05)。LEfSe分析显示,MCFA组母猪肠道真杆菌属和普雷沃氏菌属相对丰度显著高于对照组(P<0.05)。微生物相关性分析结果表明,密螺旋体属与初乳IgG含量呈显著负相关(P<0.05),普雷沃氏菌属与初乳IgM含量呈显著正相关(P<0.05)。日粮添加MCFA显著提高了仔猪血清中IgG、IgA和IgM含量(P<0.05)。[结论]日粮中添加MCFA显著提高仔猪出生重和出生窝重,提高初乳乳脂含量及免疫球蛋白IgG和IgM含量,显著提高母猪血清抗氧化能力;添加MCFA优化了母猪的肠道菌群结构,显著提高了粪便菌群的α多样性指数及拟杆菌门、纤维杆菌门、真杆菌属和普雷沃氏菌属相对丰度。综上,日粮中添加MCFA是一种有效策略,能够同时促进哺乳仔猪的生长与免疫水平,并改善母猪的繁殖性能与肠道微生态平衡。 展开更多
关键词 中链脂肪酸 母猪 繁殖性能 粪便菌群 哺乳仔猪
在线阅读 下载PDF
如何增强产业链韧性:专精特新“小巨人”认定对国内产业链嵌入的影响
16
作者 谭雪 王世豪 +1 位作者 吴延松 修宗峰 《产业经济研究》 北大核心 2026年第1期73-86,128,共15页
专精特新“小巨人”政策是实现关键技术与原材料国产替代的重要制度安排,但专精特新“小巨人”认定能否促进企业嵌入国内产业链体系以增强产业链韧性,仍缺少系统性的经验证据支持。以我国中小上市企业为研究样本,采用双重差分法检验中... 专精特新“小巨人”政策是实现关键技术与原材料国产替代的重要制度安排,但专精特新“小巨人”认定能否促进企业嵌入国内产业链体系以增强产业链韧性,仍缺少系统性的经验证据支持。以我国中小上市企业为研究样本,采用双重差分法检验中小企业获评专精特新“小巨人”对国内产业链嵌入的影响及作用机制。实证研究发现,专精特新“小巨人”认定能够促进企业嵌入国内产业链体系,这体现为“小巨人”企业国内市场份额的提高。机制分析表明,获评专精特新“小巨人”能够推动企业响应国产替代战略,也能提高企业国内市场知名度,从而促进企业国内产业链嵌入。异质性分析发现,专精特新“小巨人”认定对国内产业链嵌入的促进作用受到人力资本质量、资源充裕程度、市场化水平和行业竞争程度的影响,即当人力资本质量较高、资源充裕程度较高、市场化水平较高、行业竞争程度较高时,促进作用更为明显。经济后果检验发现,获评专精特新“小巨人”在促进中小企业嵌入国内产业链体系后,会使其进一步增加研发投入、提高专利产出并提升全要素生产率,从而达到长期稳链、强链的目的。研究揭示了专精特新“小巨人”认定促进中小企业嵌入国内产业链体系的作用机理,相关结论对如何更好地落实专精特新“小巨人”政策具有一定的启示意义。 展开更多
关键词 专精特新“小巨人”企业 中小企业 政策响应 信号传递 国内产业链嵌入
原文传递
Evaluation of dynamic effects of dietary medium-chain monoglycerides on performance,intestinal development and gut microbiota of broilers in large-scale production 被引量:2
17
作者 Tao Liu Shengyue Ruan +5 位作者 Qiufen Mo Minjie Zhao Jing Wang Zhangying Ye Li Chen Fengqin Feng 《Animal Nutrition》 SCIE CAS CSCD 2023年第3期269-280,共12页
Medium-chain monoglycerides(MG)have been reported to affect the productive performance,gut microbiota and health of broiler chickens reared in ideal experimental conditions at home and abroad.However,the effects of MG... Medium-chain monoglycerides(MG)have been reported to affect the productive performance,gut microbiota and health of broiler chickens reared in ideal experimental conditions at home and abroad.However,the effects of MG on performance,intestinal development and gut microbiota of chickens in large-scale farms during different feed stages remain unknown.The present study was conducted on a modern farm with a total of 12,000 yellow feathered broiler chicks that were randomly allotted to 2groups(1000 chicks/replicate,6 replicates/group)for a 70-day trial.The control group(CON group)received a basal diet,and the treated group(MG group)was fed a basal diet containing 300 mg/kg mixed MG.The results revealed that dietary MG significantly(P<0.05)increased the body weight and average feed intake,but notably reduced the feed conversion and mortality of chickens in large-scale production during the starter phase.The villus height of the duodenum in the MG group at 1,2 and 7 wk of age increased notably,and the villus height to crypt depth ratio at 1,2,5 and 10 wk of age was improved.Dietary MG decreased the serum insulin content of chickens at 5,7 and 10 wk of age,and decreased the serum lipopolysaccharide at 3 and 7 wk of age.The triglyceride level of chickens at 3,5 and 10 wk of age and the low-density lipoprotein cholesterol level of chickens at 7 and 10 wk of age in the MG group decreased notably,while the high-density lipoprotein cholesterol increased significantly.Moreover,MG supplementation selectively increased the relative abundance of genus Bacteroides(family Bacteroidaceae)and Lachnospiraceae_NK4A136_group,but decreased the content of genus Rikenellaceae_RC9_gut_group,Collinsella and family Barnesiellaceae in the cecum of chickens at 3,7 and 10 wk of age.Conclusively,these findings showed that dietary MG notably enhanced chicken performance,health and feed nutrient utilization at early ages by regulating gut microbiota,intestinal development and serum biochemical indices. 展开更多
关键词 medium-chain monoglycerides Broiler chickens Dynamic effect Gut microbiota Fat deposition
原文传递
基于微宇宙系统探究碳源类型对人工窖泥微生物群落结构及其代谢的影响
18
作者 朱性雪 唐云 +3 位作者 尉军强 林一心 任聪 徐岩 《食品与发酵工业》 北大核心 2026年第3期166-175,共10页
以老窖泥为种子源制备新窖泥过程中微生物群落结构变化受到碳源种类影响的机理尚不清楚。该研究目的在于探索葡萄糖和乳酸对窖泥微生物菌群重构过程中微生物代谢和群落结构的影响。该研究采用厌氧微宇宙系统,在严格厌氧条件下进行窖泥培... 以老窖泥为种子源制备新窖泥过程中微生物群落结构变化受到碳源种类影响的机理尚不清楚。该研究目的在于探索葡萄糖和乳酸对窖泥微生物菌群重构过程中微生物代谢和群落结构的影响。该研究采用厌氧微宇宙系统,在严格厌氧条件下进行窖泥培养,测定底物与代谢产物变化规律,运用扩增子测序技术分析微生物群落的动态变化特征。结果表明,模拟发酵中产己酸微生物相对丰度降低,但可正常代谢且己酸含量达到(9.52±0.23)g/kg。乳酸是窖泥微生物产己酸的重要碳源,而葡萄糖的添加减缓了短、中链脂肪酸的生成速率。窖泥制作过程不可避免出现乳酸菌大量生长现象。甲烷杆菌纲的相对丰度虽未出现较大幅度变化,但较大地压缩了拟杆菌纲和甲烷微菌纲的相对丰度。综上所述,该研究为进一步优化人工窖泥的制备过程提供了理论支持和实践依据。 展开更多
关键词 窖泥 微宇宙系统 己酸 产己酸细菌 短中链脂肪酸降解菌群
在线阅读 下载PDF
Peracetic acid(PAA)-based pretreatment effectively improves medium-chain fatty acids(MCFAs)production from sewage sludge 被引量:1
19
作者 Yufen Wang Haixiao Guo +5 位作者 Xuecheng Li Xueming Chen Lai Peng Tingting Zhu Peizhe Sun Yiwen Liu 《Environmental Science and Ecotechnology》 SCIE 2024年第4期154-166,共13页
Peracetic acid(PAA),known for its environmentally friendly properties as a oxidant and bactericide,is gaining prominence in decontamination and disinfection applications.The primary product of PAA oxidation is acetate... Peracetic acid(PAA),known for its environmentally friendly properties as a oxidant and bactericide,is gaining prominence in decontamination and disinfection applications.The primary product of PAA oxidation is acetate that can serve as an electron acceptor(EA)for the biosynthesis of medium-chain fatty acids(MCFAs)via chain elongation(CE)reactions.Hence,PAA-based pretreatment is supposed to be beneficial for MCFAs production from anaerobic sludge fermentation,as it could enhance organic matter availability,suppress competing microorganisms and furnish EA by providing acetate.However,such a hypothesis has rarely been proved.Here we reveal that PAA-based pretreatment leads to significant exfoliation of extracellular polymeric substances(EPS)from sludge flocs and disruption of proteinic secondary structures,through inducing highly active free radicals and singlet oxygen.The production of MCFAs increases substantially to 11,265.6 mg COD L^(-1),while the undesired byproducts,specifically long-chain alcohols(LCAs),decrease to 723.5 mg COD L^(-1).Microbial activity tests further demonstrate that PAA pretreatment stimulates the CE process,attributed to the up-regulation of functional genes involved in fatty acid biosynthesis pathway.These comprehensive findings provide insights into the effectiveness and mechanisms behind enhanced MCFAs production through PAA-based technology,advancing our understanding of sustainable resource recovery from sewage sludge. 展开更多
关键词 Sewage sludge medium-chain fatty acids(MCFAs) Extracellular polymeric substances(EPS) Peracetic acid(PAA) Metabolic activity
原文传递
Efficacy and safety of modified medium-chain triglyceride ketogenic diet in patients with drug-resistant epilepsy
20
作者 Hua Li Yao Wang +5 位作者 Jing Guo Peiqi Zhang Zheng Xu Kai Peng Xiaoli Dong Liming Zhao 《Acta Epileptologica》 2024年第1期44-52,共9页
Background Medium-chain triglyceride ketogenic diet(MCTKD)is previously less commonly used in China.This study was aimed to assess the efficacy and safety of the modified MCTKD in the treatment of drug-resistant epile... Background Medium-chain triglyceride ketogenic diet(MCTKD)is previously less commonly used in China.This study was aimed to assess the efficacy and safety of the modified MCTKD in the treatment of drug-resistant epilepsy in Chinese patients.Methods Patients with drug-resistant epilepsy were enrolled to receive treatment with modified MCTKD in Guangdong Sanjiu Brain Hospital during December 2020 and September 2022.The modified MCTKD contained fat that provided 50–70%of the total energy,as well as proteins and carbohydrates that provided 20–30%and 20%of energy,respectively.The fat component was composed of 20–30%medium-chain triglycerides(MCTs)and 30–40%long-chain triglycerides.The efficacy and safety of the diet were assessed at 1,3 and 6 months.Results A total of 123 patients aged 2.5 to 65 years,were included in this study.The response rates at 1,3 and 6 months were 49.6%,43.1%,and 30.9%,respectively.The seizure freedom rates at 1,3 and 6 months were 12.2%,10.6%,and 6.5%,respectively.The retention rates at 1,3 and 6 months were 98.4%,65.0%and 33.3%respectively.Side effects occurred in 21.14%of patients,which were predominantly gastrointestinal symptoms such as abdominal pain,diarrhea,vomiting,and constipation,and most of them resolved after dietary adjustments.A total of 82 patients(66.7%)discontinued the treatment with the reason of refusing to eat(8.1%),poor efficacy(35.0%),poor compliance(4.9%),and inability to follow-up(9.8%).Only 4 patients(3.3%)withdrew the diet due to side effects.Conclusions The modified MCTKD with MCTs providing 20–30%of energy has a good safety in patients with drug-resistant epilepsy,but its effectiveness needs to be enhanced.Further modifications of MCTKD with an optimal energy ratio are required to achieve a better efficacy and safety. 展开更多
关键词 medium-chain triglyceride ketogenic diet Ketogenic diet Drug-resistant epilepsy EFFICACY Safety
原文传递
上一页 1 2 46 下一页 到第
使用帮助 返回顶部