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Cardamonin as a potential anticancer agent:Preclinical insights and clinical implications
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作者 Nassrin A Badroon Abdulsamad Alsalahi +2 位作者 Musheer A Aljaberi Nazia Abdul Majid Mohammed Abdullah Alshawsh 《World Journal of Clinical Oncology》 2025年第11期103-121,共19页
Cardamonin is a natural chalcone that has been extensively investigated for its anticancer activity.However,its clinical relevance is still not explicit,limiting its progression into clinical trials and highlighting a... Cardamonin is a natural chalcone that has been extensively investigated for its anticancer activity.However,its clinical relevance is still not explicit,limiting its progression into clinical trials and highlighting a persistent gap between preclinical evidence and practical application.This review aims to assess the readiness of cardamonin to progress from laboratory research to clinical application as an anticancer agent by examining both scientific evidence and translational challenges.Preclinical pharmacokinetic and pharmacodynamic data suggest that cardamonin’s therapeutic potential as an anticancer agent is hindered by its poor oral bioavailability.Although its molecular targets remain undefined,evidence indicates that cardamonin can inhibit various signaling pathways,including nuclear factor kappa-light-chain-enhancer of activated B cells,mammalian target of rapamycin,signal transducer and activator of transcription 3,and Wnt/β-catenin.The lack of in vivo toxicity studies creates uncertainty regarding the balance between its therapeutic benefits and potential adverse effects when moving from laboratory research to human trials.Despite these limitations,cardamonin has,however,demonstrated antiproliferative,anti-metastatic,and chemosensitizing effects,mainly against breast,colorectal,and ovarian cancers.Nevertheless,exploring its combination with standard chemotherapeutic agents may offer a promising foundation for advancing cardamonin into clinical trials. 展开更多
关键词 CARDAMONIN PHARMACODYNAMICS Pharmacokinetics CHALCONES FLAVONOIDS ANTICANCER Preclinical studies
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Oral Gd-DTPA as a negative gastrointestinal contrast agent in magnetic resonance cholangiopancreatography
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作者 陈燕萍 张雪林 +1 位作者 昌仁民 成官迅 《Journal of Medical Colleges of PLA(China)》 CAS 2003年第5期325-330,共6页
Objective: To evaluate the value of oral Gd-DTPA as a negative contrast agent during magnetic resonance cholangiopancreatography (MRCP) to eliminate the high signals of the gastrointestinal tract. Methods: To select t... Objective: To evaluate the value of oral Gd-DTPA as a negative contrast agent during magnetic resonance cholangiopancreatography (MRCP) to eliminate the high signals of the gastrointestinal tract. Methods: To select the optimal concentration of oral Gd-DTPA for MRCP, a phantom study was performed followed by clinical trial in 15 cases undergoing MRCP before and after oral Gd-DTPA (in a total volume of 250 ml 1∶5 diluted Gd-DTPA, 1.488 g/L). MRCP images were acquired using two-dimensional single slice fast spin-echo (SSTSE) sequence and half-Fourier acquisition single slice fast spin-echo (HASTE) sequence. Results: The phantom study showed that the 1∶5 diluted oral Gd-DTPA was best in decreasing the signal intensity both in T2-weighted imaging (59.5%) and in HASTE sequence (82.45%). The high signal intensity of the stomach and intestinal fluid was completely suppressed in all the cases. The depictions of the common bile duct and pancreatic duct were markedly improved by using the oral contrast agent (P<0.05). Conclusion: Oral Gd-DTPA is effective and safe for eliminating the high signal of the gastrointestinal tract to improve the depiction of the biliary system by MRCP. 展开更多
关键词 magnetic resonance cholangiopancreatography oral contrast agent pancreaticobiliary system gadolini-um-DTPA
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Toxicity Study of Anti-HABs Agents on Penaeus chinensis
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作者 孙晓霞 张波 俞志明 《Marine Science Bulletin》 CAS 2001年第1期51-54,共4页
In order to study the effect of anti-HABs agents on Penaeus chinensis, the toxicity experiments on clay, Ca(ClO)2, FeCl3, and AlCl3 to Penaeus chinensis are carried out. The results show that: (1) the clay isn't t... In order to study the effect of anti-HABs agents on Penaeus chinensis, the toxicity experiments on clay, Ca(ClO)2, FeCl3, and AlCl3 to Penaeus chinensis are carried out. The results show that: (1) the clay isn't toxic to Penaeus chinensis; (2) Ca(ClO)2 has no toxicity to Penaeus chinensis at low levels, but has acute and chronic toxicity at high levels; (3) Penaeus chinensis can accumulate Fe and Al. The toxic effect needs further study. 展开更多
关键词 HABs anti-HABs agents PENAEUS chinensis TOXICITY
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A PRELIMINARY STUDY OF THE EFFECTS OF CHEMOTHERAPEUTICAGENTS IN COMBINATION WITH CHINESE HERBAL COMPOUNDS AS IMMUNOMODULATORS IN MOUSE S_(180)
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作者 金杏泉 陆婉琴 +1 位作者 徐静芳 孙曾一 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1989年第2期76-79,共4页
The effect of the Chinese herbal compound (CHC) on solid sarcoma 180 (S180) in Swiss mice was studied either alone or in combination with 5-fluorouracil (5FU), cyclophosphamide (CYT) or mitomycin C (MMC). The prelimin... The effect of the Chinese herbal compound (CHC) on solid sarcoma 180 (S180) in Swiss mice was studied either alone or in combination with 5-fluorouracil (5FU), cyclophosphamide (CYT) or mitomycin C (MMC). The preliminary results indicated that combination treatment seemed to possess better antitumor activity than chemotherapy alone. The treatment with CHC alone however had neither an obvious antitumor effect in tumor bearing mice nor toxicity in normal mice. These results show that CHC may stimulate organs of the immune system such as the spleen to be im-munomodulators and enhance the antitumor activity of some chemotherapeutic agents. 展开更多
关键词 CHC A PRELIMINARY STUDY OF THE EFFECTS OF CHEMOTHERAPEUTICAGENTS IN COMBINATION WITH CHINESE HERBAL COMPOUNDS AS IMMUNOMODULATORS IN MOUSE S SFU
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EFFECTS OF VARIOUS VASOACTIVE AGENTS ON TUMOR BLOOD FLOW IN RAT
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作者 李玉林 于洪藻 +2 位作者 张丽红 李浩川 金松杰 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1993年第2期41-46,共6页
Effects of angiotensin Ⅱ and other six vasoactive agents on tissue blood flow of Yoahida rat ascites hepatoma AH109A and normal liver were measured by the hydrogen clearance method. The mean blood flow in the tumor p... Effects of angiotensin Ⅱ and other six vasoactive agents on tissue blood flow of Yoahida rat ascites hepatoma AH109A and normal liver were measured by the hydrogen clearance method. The mean blood flow in the tumor peripheral part under normal tension was 11. 9±8. 2ml/ min/100g tissue and was not influenced by tumor size. Tumor blood flow was more significantly increased in infusion angiotensin Ⅱthan 0.5mg/ ml methoxamine, however, normal liver blood flow of tumor-bearing rats was unchanged in contrast to an Increase seen in the tumor. A pronounced reduction of tumor blood flow was found after administration of epinephrine, norepinephrin and ethylphenylephrine. In addition, metaraminol and phenyleprine as well as 1. 0 and 2. 5mg/ ml methoxamine were not found to significantly change blood flow of the tumor. 展开更多
关键词 Tumor blood flow Vasoactive agents Anglotensin Induced hypertension chemotherapy Rat ascites hepatoma
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Synthesis and biological evaluation of 12-benzyl matrinic amide derivatives as a novel family of anti-HCV agents 被引量:4
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作者 Sheng Tang Zong-Gen Peng +5 位作者 Xin Zhang Xin-Yue Cheng Wen-Jing Li Jian-Dong Jiang Ying-Hong Li Dan-Qing Song 《Chinese Chemical Letters》 SCIE CAS CSCD 2016年第7期1052-1057,共6页
A new series of 12-benzyl matrinic amide/ethanamide derivatives were synthesized from matrinine(1)and evaluated for their anti-HCV activity,taking compound 2 as the lead.SAR revealed that the introduction of a suita... A new series of 12-benzyl matrinic amide/ethanamide derivatives were synthesized from matrinine(1)and evaluated for their anti-HCV activity,taking compound 2 as the lead.SAR revealed that the introduction of a suitable substituent at the N’-end of matrinic amide might greatly enhance the potency.Among them,matrinic acid 17 and N’-substituted matrinic amides 18a-d exhibited promising potency with low micromolar EC50 values ranging from 1.03μmol/L to 7.54 μmol/L,and better therapeutic window with SI from 66 to 132.Moreover,compound 17 displayed an excellent PK and safety profile in vivo,demonstrating good drug-like characteristics.Thus,it has been selected for further investigation,with an advantage of decreased chances of inducing drug-resistance mutations. 展开更多
关键词 Matrinic acid Matrinic amide Hepatitis C virus Structure–activity relationship
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Anti‑leishmanial and Anti‑inflammatory Agents from Endophytes:A Review 被引量:3
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作者 Rufin Marie Kouipou Toghueo 《Natural Products and Bioprospecting》 CAS 2019年第5期311-328,共18页
Leishmaniases and chronic inflammatory diseases are the cause of millions of deaths in the world each year.The treatment of leishmaniasis is facing serious drawbacks particularly due to the limited number of effective... Leishmaniases and chronic inflammatory diseases are the cause of millions of deaths in the world each year.The treatment of leishmaniasis is facing serious drawbacks particularly due to the limited number of effective medicines,the resistance,and the toxicity of available drugs.On the other hand,many drugs are used for the management of inflammatory disorders.However,the most commonly prescribed although efficient is highly toxic with multiples side effects.New leads compounds for the development of new anti-leishmanial and anti-inflammatory drugs are needed.Over the past decade,several studies on the potential of endophytes to produce bioactive metabolites have been reported.We are presenting in the present review the status of research from 2000 to 2019 on the anti-leishmanial and anti-inflammatory metabolites isolated from endophytes from diverse habitats.An emphasis was put on existing gaps in the literature to inspire and guide future investigations.We hope that this review will help accelerate the drug discovery against leishmaniases and inflammation-associated disorders. 展开更多
关键词 Anti-leishmanial ANTI-INFLAMMATORY ENDOPHYTES Bioactive metabolites
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Collaborative Problem in Multi-agent System 被引量:1
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作者 林琳 钟诗胜 王知行 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2004年第2期191-195,共5页
In the MAS, system goal task can be decomposed into many transactions, which will be achieved by special agents distributed in different physical space. Due to complex coupling relations among transactions, transactio... In the MAS, system goal task can be decomposed into many transactions, which will be achieved by special agents distributed in different physical space. Due to complex coupling relations among transactions, transactions may form Waiting-Circle resulting in deadlock. Concerning the problem, this paper proposes two theorems developed for Waiting-Circle detection in transaction set and ensures the implement of goal task decomposition result. Furthermore, Circle-First Search is put forward to search all of the Waiting-Circle, which prnvide the basic guideline for decomposing goal task again and eliminate Waiting-Circle. 展开更多
关键词 MAS waiting-circle circle-first search
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Novel cyclometalated iridium(Ⅲ)phosphine-imine(P^N)complexes:highly efficient anticancer and anti-lung metastasis agents in vivo
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作者 Zhishan Xu Yuliang Yang +5 位作者 Xianglei Jia Lihua Guo Xingxing Ge Genshen Zhong Shujiao Chen Zhe Liu 《Inorganic Chemistry Frontiers》 2020年第5期1273-1283,共11页
Herein,a new class of iridium(Ⅲ)-based metal complexes with phosphine-imine(P^N)ligands are synthesized and authenticated.These complexes show high cytotoxicities against seven cancer cells in vitro.Simultaneously,an... Herein,a new class of iridium(Ⅲ)-based metal complexes with phosphine-imine(P^N)ligands are synthesized and authenticated.These complexes show high cytotoxicities against seven cancer cells in vitro.Simultaneously,antitumor mechanism studies show that complex Ir3 induces apoptosis by depolarization of mitochondrial membrane potential,ROS overproduction and ROS-mediated DNA damage.Importantly,BIX01294,a G9a histone methyltransferase inhibitor,could markedly sensitize Ir3-induced cytotoxicity,cell cycle arrest,apoptosis and inhibition of migration in HCT116 cancer cells in vitro.Finally,we show that combined treatment with Ir3 and BIX01294 potently inhibits tumour growth and lung metastasis in vivo.Taken together,we demonstrate that BIX01294 could potently sensitize iridium(Ⅲ)-based metal complex-induced inhibition of tumour progression and provide the basis for developing new metal-based anticancer agents and therapeutic strategies in vivo for effective cancer therapy. 展开更多
关键词 depolarization mitochondrial membrane potentialros mechanism studies iridium based metal complexes anticancer agents anti lung metastasis cancer cells apoptosis phosphine imine p n ligands
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Dual-functional cyclometalated iridium imine NHC complexes:highly potent anticancer and antimetastatic agents
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作者 Zhenzhen Tian Yuliang Yang +3 位作者 Lihua Guo Genshen Zhong Juanjuan Li Zhe Liu 《Inorganic Chemistry Frontiers》 2018年第12期3106-3112,共7页
A new class of cyclometalated iridium(III)complexes with imine-N-heterocyclic carbenes(NHC)as ligands were synthesized and fully characterized.One crystal structure is reported.All the six complexes exhibited highly p... A new class of cyclometalated iridium(III)complexes with imine-N-heterocyclic carbenes(NHC)as ligands were synthesized and fully characterized.One crystal structure is reported.All the six complexes exhibited highly potent anticancer activity against A549 cells,HeLa cells,HepG2 cells,GL261 cells and A549R cells.In particular,they were up to 9 and 37 times more potent than clinically used anticancer drug cisplatin towards A549 and A549R cell lines,respectively.Remarkably,mechanism studies showed that the complexes pass into cancer cells through an energy-dependent pathway and cause apoptosis via reactive oxygen species(ROS)generation,mitochondrial membrane potential dysfunction,and lysosomal damage.In addition,complex Ir6 effectively impeded cell migration and colony formation. 展开更多
关键词 r cell cyclometalated anticancer anticancer drug imine n heterocyclic carbenes NHC crystal structure anticancer activity dual functional
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Development and Implementation of a Technique for Norms-Adaptable Agents in Open Multi-Agent Communities 被引量:1
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作者 MAHMOUD Moamin AHMAD Mohd Sharifuddin MOHD YUSOFF Mohd Zaliman 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2016年第6期1519-1537,共19页
In open normative multi-agent communities,an agent is not usually and explicitly given the norms of the host agents.Thus,when it is not able to adapt the communities's norms,it is totally deprived of accessing res... In open normative multi-agent communities,an agent is not usually and explicitly given the norms of the host agents.Thus,when it is not able to adapt the communities's norms,it is totally deprived of accessing resources and services from the host.Such circumstance severely affects its performance resulting in failure to achieve its goal.Consequently,this study attempts to overcome this deficiency by proposing a technique that enables an agent to detect the host's potential norms via self-enforcement and update its norms even in the absence of sanctions from a third-party.The authors called this technique as the potential norms detection technique(PNDT).The PNDT consists of five components: Agent's belief base; observation process; potential norms mining algorithm(PNMA);verification process; and updating process.The authors demonstrate the operation of the PNMA algorithm by testing it on a typical scenario and analyzing the results on several perspectives.The tests' results show that the PNDT performs satisfactorily albeit the success rate depends on the environment variables settings. 展开更多
关键词 Agent-based simulation normative agent norms deatetcin self-enforcement agent.
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微创外科领域全球专利竞争格局与中国创新策略研究
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作者 蒋薇薇 徐懿萍 +3 位作者 陈喆 朱佳敏 宋缨 周岚 《中国发明与专利》 2026年第3期45-55,共11页
[目的/意义]本文通过对近20年微创外科领域专利数据的多维度系统研究,旨在把握产业技术的演进规律并为制定创新发展策略提供科学依据。[方法/过程]通过对微创外科领域专利趋势、来源地与目标地、专利流向、申请人、法律状态、热点技术... [目的/意义]本文通过对近20年微创外科领域专利数据的多维度系统研究,旨在把握产业技术的演进规律并为制定创新发展策略提供科学依据。[方法/过程]通过对微创外科领域专利趋势、来源地与目标地、专利流向、申请人、法律状态、热点技术及专利质量等方面进行系统分析,揭示了该领域技术创新发展的路径、竞争态势及未来趋势。[结果/结论]研究表明,中国微创外科产业正处于从“规模制造”向“创新引领”转型的关键期,需通过加强基础研究、优化专利布局、推动智能化升级等策略提升国际竞争力。本研究为制定医疗器械产业创新政策提供了数据支撑和决策参考。 展开更多
关键词 专利 创新 微创外科 介入治疗
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鹿蹄草素对产肠毒素大肠杆菌的抑菌效果及作用机制
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作者 陈默 高婷 +3 位作者 刘威 朱佳佳 周丹娜 李鹏 《黑龙江畜牧兽医》 北大核心 2026年第2期1-7,共7页
为了探究鹿蹄草素对产肠毒素大肠杆菌(enterotoxingenic Escherichia coli,ETEC)的抑菌效果及其作用机制,试验采用微量肉汤稀释法测定鹿蹄草素及抗生素对ETEC K99菌株的最小抑菌浓度(minimal inhibitory concentration, MIC),采用时间-... 为了探究鹿蹄草素对产肠毒素大肠杆菌(enterotoxingenic Escherichia coli,ETEC)的抑菌效果及其作用机制,试验采用微量肉汤稀释法测定鹿蹄草素及抗生素对ETEC K99菌株的最小抑菌浓度(minimal inhibitory concentration, MIC),采用时间-杀菌动力学曲线研究鹿蹄草素(128,256,512μg/mL)对ETEC K99菌株的杀菌活性,采用结晶紫染色法定量分析鹿蹄草素(16,32,64,128,256μg/mL)对ETEC K99菌株生物被膜形成的影响,采用ATP检测试剂盒评估鹿蹄草素(32,64,128,256μg/mL)对ETEC K99菌株细胞膜通透性的影响,利用体外细胞模型评估鹿蹄草素(64,128,256μg/mL)对ETEC K99菌株黏附与侵入能力的影响,采用分子对接技术预测鹿蹄草素作用ETEC K99菌株的靶点。结果表明:磺胺异口恶唑对大肠杆菌抑制作用弱,鹿蹄草素对大肠杆菌有抑制效果,且使用512μg/mL鹿蹄草素处理ETEC K99菌株4 h后,细菌被完全杀死,鹿蹄草素对ETEC K99菌株在体外有直接抑制和杀灭作用,且抑菌作用呈剂量依赖性。当鹿蹄草素质量浓度≥32μg/mL时,可显著或极显著降低ETEC K99菌株生物被膜的OD590值(P<0.05或P<0.001、P<0.0001),其最低有效抑制质量浓度为32μg/mL。与阴性对照(只添加菌液)相比,鹿蹄草素质量浓度为32~256μg/mL时荧光强度极显著降低(P<0.01、P<0.000 1),说明鹿蹄草素能够通过剂量依赖方式增加ETEC K99菌株内膜通透性,导致胞内ATP外泄;当鹿蹄草素质量浓度为64,128μg/mL时,荧光强度显著增强(P<0.05);鹿蹄草质量浓度为128μg/mL时,荧光强度极显著增强(P<0.001)。高质量浓度鹿蹄草素可显著破坏细菌外膜完整性。鹿蹄草素质量浓度为64μg/mL时,细胞表面黏附的活菌数减少22.4%(P<0.05),细胞内侵袭菌数减少36.8%(P<0.01);鹿蹄草素质量浓度为128,256μg/mL时,细胞表面黏附的活菌数分别减少63.8%(P<0.001)和79.8%(P<0.000 1),细胞内侵袭菌数分别减少51.3%(P<0.01)和66.8%(P<0.01)。ETEC K99的纤毛蛋白FanA可能通过π-氢键(自由结合能-17.39 kJ/mol)与鹿蹄草素结合。说明鹿蹄草素可能通过改变ETEC膜的通透性、抑制其生物被膜形成及干扰黏附侵袭功能等多途径发挥抑菌作用。 展开更多
关键词 鹿蹄草素 产肠毒素大肠杆菌 抑菌效果 分子对接 细菌膜 生物被膜
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野生平菇产纤维素酶发酵条件的优化
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作者 王君 陈琳 +3 位作者 白家梁 朱亚男 宋立立 胡高爽 《中国饲料》 北大核心 2026年第1期51-58,共8页
纤维素是可再生资源,来源广泛,但利用率却偏低。平菇等一些腐生型微生物可以产生纤维素酶、漆酶等将其降解。本试验选用实验室保藏的一种野生平菇菌株,通过单因素试验探究培养基成分及发酵条件对平菇产纤维素酶能力的影响。选出影响较... 纤维素是可再生资源,来源广泛,但利用率却偏低。平菇等一些腐生型微生物可以产生纤维素酶、漆酶等将其降解。本试验选用实验室保藏的一种野生平菇菌株,通过单因素试验探究培养基成分及发酵条件对平菇产纤维素酶能力的影响。选出影响较大的三个因素即温度、磷酸盐浓度、发酵天数。然后以纤维素酶酶活力为评价指标,进行响应面试验。结果表明:平菇产酶发酵的最佳条件为温度20℃,磷酸盐浓度0.2%,发酵天数5 d,接种量10%,转速150 r/min,装液量50 mL,pH 7,在此条件下平菇产纤维素酶的酶活力为12.6375 U/mL。此次试验结果可为后续研究平菇产纤维素酶能力提供一定的理论依据。 展开更多
关键词 纤维素酶 单因素试验法 响应面试验法 平菇
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鸡痘病毒HB株的分离鉴定及致病性分析
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作者 桂焱垚 张高峰 +9 位作者 李丽 冯贺龙 姚伦 曾哲 聂仁锋 罗青平 温国元 欧长波 商雨 汪宏才 《动物医学进展》 北大核心 2026年第4期7-12,共6页
本研究旨在确定送检病鸡的病原,并对该病原进行分离鉴定和致病性分析。采集该病鸡的病变组织处理后进行PCR检测;将阳性样品接种SPF鸡胚的尿囊膜,通过PCR检测、基因测序分析、动物回归试验、病理组织学观察等方法进行鉴定。结果显示,用... 本研究旨在确定送检病鸡的病原,并对该病原进行分离鉴定和致病性分析。采集该病鸡的病变组织处理后进行PCR检测;将阳性样品接种SPF鸡胚的尿囊膜,通过PCR检测、基因测序分析、动物回归试验、病理组织学观察等方法进行鉴定。结果显示,用鸡痘病毒(Fowlpox virus,FPV)特异性引物扩增时出现特异性条带,大小符合预期。经鸡胚传代,发现尿囊膜有明显的痘斑、增厚等病变;通过PCR检测和测序,确定分离的病原为FPV,并命名为HB-FPV;P4b基因的遗传进化分析表明,该分离株与国内外分离的禽痘病毒的同源性在92.4%~99.6%;动物回归试验显示,攻毒鸡眼睑处被痘疹覆盖,皮肤表面包括鸡冠、喙、爪子等少毛部位弥漫性分布凸起的痘痂,痘痂大小不一,易于剥离。组织病理学观察显示,鸡冠病变组织中的结缔组织断裂、稀疏,伴有炎性细胞浸润。综上所述,本研究成功分离并鉴定出一株具有致病性的FPV,为FPV的流行病学分析以及弱毒疫苗的研发等提供了参考依据。 展开更多
关键词 鸡痘病毒 P4b基因 遗传进化 致病性
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Identification of anti-Gram-negative bacteria agents targeting the interaction between ribosomal proteins L12 and L10 被引量:4
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作者 Weiwei Wang Chao Liu +5 位作者 Ningyu Zhu Yuan Lin JiANDong Jiang Yanchang Wang Yan Li Shuyi Si 《Acta Pharmaceutica Sinica B》 SCIE CAS CSCD 2018年第5期772-783,共12页
Gram-negative bacteria have become the main pathogens and cause serious clinical problems with increased morbidity and mortality. However, the slow discovery of new antimicrobial agents is unable to meet the need for ... Gram-negative bacteria have become the main pathogens and cause serious clinical problems with increased morbidity and mortality. However, the slow discovery of new antimicrobial agents is unable to meet the need for the treatment of bacterial infections caused by drug-resistant strains. The interaction of L12 and L10 is essential for ribosomal function and protein synthesis. In this study, a yeast two-hybrid system was established to successfully detect the interaction between L12 and L10 proteins from gram-negative bacteria Escherichia coli, which allows us to screen compounds that specifically disrupt this interaction. With this system, we identified two compounds IMB-84 and IMB-87 that block L12-L10 interaction and show bactericidal activity against E. coli. We used glutathione-S-transferase(GST) pull-down and surface plasmon resonance(SPR) assays to demonstrate that these compounds disrupt L12-L10 interaction in vitro and the target of compounds was further confirmed by the overexpression of target proteins. Moreover, protein synthesis and elongation factor G-dependent GTPase activities are inhibited by two compounds. Therefore, we have identified two antibacterial agents that disrupt L12-L10 interaction by using yeast two-hybrid system. 展开更多
关键词 YEAST TWO-HYBRID ESCHERICHIA COLI RIBOSOME L12/L10 Antimicrobial AGENTS
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资源约束下一次性成败型装备多类型试验优化设计方法
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作者 王语晨 杨宝庆 +2 位作者 马杰 郑小鹏 刘闻 《宇航学报》 北大核心 2026年第2期353-365,共13页
为解决一次性成败型装备在数字仿真、半实物仿真及特小子样飞行试验资源约束下的多类型序贯试验优化设计难题,实现对其任务成功概率的高效评估,提出一种基于贝叶斯理论的序贯试验智能优化设计方法。利用改进的陆军装备系统分析中心(AMS... 为解决一次性成败型装备在数字仿真、半实物仿真及特小子样飞行试验资源约束下的多类型序贯试验优化设计难题,实现对其任务成功概率的高效评估,提出一种基于贝叶斯理论的序贯试验智能优化设计方法。利用改进的陆军装备系统分析中心(AMSAA)模型,融合数字仿真试验、半实物仿真试验和先前研制阶段试验的试验数据,预测装备任务成功概率;采用对抗深度Q网络强化学习算法训练优化策略,实现对数字仿真、半实物仿真与飞行试验类型的序贯自适应决策。装备仿真平台试验与对比分析表明,该方法能够根据试验进程动态调整试验策略,在满足评估要求的同时显著降低试验资源消耗。该方法为资源受限条件下,一次性装备多类型试验的智能优化设计提供了有效途径,能够保证特小飞行子样约束下的试验评估性能。 展开更多
关键词 特小子样 试验设计 装备研制试验 强化学习 贝叶斯定理
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洱海流域小农户模式下施用不同品牌鸡粪肥对鲜食玉米农艺性状及产量的影响
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作者 车怡娇 吕治兵 +4 位作者 汪敏 李进荣 王彦军 张玉娇 李健强 《中国农业大学学报》 北大核心 2026年第4期44-58,共15页
洱海流域是云南典型的以小农户模式为主的高原湖泊鲜食玉米种植生产基地,为探究不同品牌鸡粪肥作为基肥施用在洱海流域的应用效果及潜在风险,选择洱海流域的主要鲜食玉米品种“农科糯336”、“京紫糯219”、“SBS902”和“天紫23”为供... 洱海流域是云南典型的以小农户模式为主的高原湖泊鲜食玉米种植生产基地,为探究不同品牌鸡粪肥作为基肥施用在洱海流域的应用效果及潜在风险,选择洱海流域的主要鲜食玉米品种“农科糯336”、“京紫糯219”、“SBS902”和“天紫23”为供试品种,设置品牌1鸡粪有机肥(T1)、品牌2干鸡粪肥(T2)、品牌3干鸡粪肥(T3)和不施肥(CK)共4个处理,采用裂区试验设计,探究不同品牌鸡粪肥对种子萌发特性、幼苗安全性(烧苗率)、关键农艺性状指标及产量的影响。结果表明:1)浸提液处理结果显示T1处理发芽指数>70%,符合要求,而T2和T3处理显著抑制种子萌发,发芽率相较CK降低6.8%~27.6%,胚根长缩减6.9%~55.7%;田间施用鸡粪肥后,T2和T3处理烧苗率达1.3%~10.7%,显著高于T1(≤1.1%)和CK(≤0.6%)(P<0.05),其中,“天紫23”各处理下的烧苗率普遍低于其他品种。2)3种鸡粪肥田间施用均能提高鲜食玉米株高、叶绿素相对含量及干物质总积累量,显著提高鲜食玉米的单穗重和产量(P<0.05)。其中,T2处理下4个鲜玉米品种产量均达到最高,平均增产幅度达15.2%~28.3%,T1和T3处理下平均增产幅度则为5.7%~19.1%。综上,洱海流域常用的2个品牌的干鸡粪肥(T2和T3)对鲜食玉米呈现增产潜力与苗期风险并存的双重效应。本研究建议小农户采用“以种定肥”的策略:优先选用腐熟度高的标准化鸡粪有机肥(T1);或者选用干鸡粪肥搭配耐受性强的品种(“天紫23”)以有效规避施用风险。既适配小农户实际生产需求,也为区域种养循环优化与农业面源污染协同治理提供技术支持。 展开更多
关键词 洱海流域 鸡粪有机肥 干鸡粪肥 鲜食玉米
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内嵌锚具夹持CFRP板与混凝土锚固性能研究
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作者 李志远 曲福来 +2 位作者 许哲 刘中良 刘桂荣 《华北水利水电大学学报(自然科学版)》 北大核心 2026年第2期111-117,共7页
【目的】为了改善混凝土表层嵌贴CFRP板与混凝土之间的黏结性能,提出了一种新型内嵌锚具加固方法。【方法】利用螺栓对钢制锚具挤压产生的夹持力实现对CFRP板的机械锚固,完成了3种直径锚具在不同螺栓拧紧力矩下的夹持力和锚固力的测试研... 【目的】为了改善混凝土表层嵌贴CFRP板与混凝土之间的黏结性能,提出了一种新型内嵌锚具加固方法。【方法】利用螺栓对钢制锚具挤压产生的夹持力实现对CFRP板的机械锚固,完成了3种直径锚具在不同螺栓拧紧力矩下的夹持力和锚固力的测试研究,并在此基础上开展了9个表层嵌贴CFRP板的黏结试件和24个内嵌锚具夹持CFRP板的锚固试件的单面剪切试验,研究了两种试件的破坏形态、CFRP板的应变分布规律、锚固力等。【结果】在测试中,锚固试件出现了锚具与CFRP板间的相对滑移破坏以及CFRP板被拉断破坏。3种直径锚具夹持的CFRP板锚固试件的锚固力不受混凝土强度和锚具间距的影响;较大直径锚具具有较大的锚固力;锚具数量的增加可有效提高试件的锚固力。【结论】揭示了内嵌锚具夹持CFRP板的传力机理,推导出多种锚具的锚固力计算公式,为内嵌锚具夹持CFRP板加固构件的设计与性能评估提供理论支撑。 展开更多
关键词 内嵌锚具 CFRP板 锚固性能 表层嵌贴 夹持力
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A UNIFIED SPECIFICATION FORMAT FOR INTERLEVEL RELATIONS BETWEEN AGENT MODELS IN MULTIPLE ABSTRACTION DIMENSIONS
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作者 JAN TREUR 《International Journal of Modeling, Simulation, and Scientific Computing》 EI 2013年第1期69-95,共27页
Multi-agent systems for a certain application area can be modeled at multiple levels of abstraction.Interlevel relations are a means to relate models from different abstraction levels.Three dimensions of abstraction o... Multi-agent systems for a certain application area can be modeled at multiple levels of abstraction.Interlevel relations are a means to relate models from different abstraction levels.Three dimensions of abstraction often occurring are the process abstraction,temporal abstraction,and agent cluster abstraction dimension.In this paper a unifying formalization is presented that can be used as a framework to specify interlevel relations for any of such dimensions.The approach is illustrated by showing how a variety of different types of abstraction relations between multi-agent system models can be formally specified in a unified manner. 展开更多
关键词 Multi-agent model interlevel relation SPECIFICATION
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