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枯草芽孢杆菌漆酶的理性设计及在霉菌毒素降解的应用
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作者 乐琛 王晓 +3 位作者 谢珂 郑艳丽 杨江科 雷磊 《食品与发酵工业》 CAS CSCD 北大核心 2024年第17期1-10,共10页
为解决目前制约食品等领域发展的霉菌毒素污染问题,选取了枯草芽孢杆菌来源的BsCotA漆酶并且通过理性设计提高酶活力、稳定性,从而实现对霉菌毒素降解效率的提高。利用理性设计改造BsCotA漆酶,获得了4个突变体漆酶,包括3个点突变体CotA^... 为解决目前制约食品等领域发展的霉菌毒素污染问题,选取了枯草芽孢杆菌来源的BsCotA漆酶并且通过理性设计提高酶活力、稳定性,从而实现对霉菌毒素降解效率的提高。利用理性设计改造BsCotA漆酶,获得了4个突变体漆酶,包括3个点突变体CotA^(A344K)、CotA^(A317T)、CotA^(T36Y),和突变整合体CotAgold,使用毕赤酵母进行异源表达,测定其酶学性质,并检测其对霉菌毒素的降解效率。基于蛋白质结构进行设计的3个单点突变,均从不同程度上提高了漆酶的稳定性。而将3个突变位点同时整合到1个漆酶突变体上时,3个突变位点间未发生显著拮抗作用,使得突变整合体CotAgold展示出最好的稳定性以及催化能力;CotAgold比酶活力为99.4 U/mg,相比BsCotA的比酶活力提高了10倍,对于ABTS的k_(cat)/K_(M)达到了7.12×10^(5)L/(mol·s),相比BsCotA提高了1.9倍;突变体CotAgold的最适反应pH值为4,最适反应温度均为70℃,与野生型BsCotA催化条件保持一致;CotAgold在pH 2~12,孵育30 min,剩余酶活力均在70%以上,相比野生型BsCotA在酸性条件下的稳定性有明显提高;CotAgold在40~90℃,孵育30 min,残留酶活力均在90%以上,相比野生型BsCotA在高温条件下的稳定性有明显提高;并在ABTS阳离子自由基作为介体的条件下,漆酶CotAgold能完全降解黄曲霉毒素B1和玉米赤霉烯酮;相比之下,野生型漆酶BsCotA的降解率仅为5%。通过蛋白质的理性设计得到了漆酶突变体CotAgold,表现出显著提高的pH稳定性以及热稳定性,蛋白表达量也有一定的提高,在霉菌毒素降解等领域具有良好的应用前景。 展开更多
关键词 漆酶 理性设计 酶学性质 毒素降解 黄曲霉毒素B1 玉米赤霉烯酮
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PHD17 acts as a target of miR1320 to negatively control cold tolerance via JA-activated signaling in rice 被引量:1
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作者 Yan Wang Yang Shen +6 位作者 Weifeng Dong Xiaoxi Cai Junkai Yang yue chen Bowei Jia Mingzhe Sun Xiaoli Sun 《The Crop Journal》 SCIE CSCD 2024年第5期1447-1458,共12页
Plant Homeo Domain(PHD)proteins are involved in diverse biological processes during plant growth.However,the regulation of PHD genes on rice cold stress response remains largely unknown.Here,we reported that PHD17 neg... Plant Homeo Domain(PHD)proteins are involved in diverse biological processes during plant growth.However,the regulation of PHD genes on rice cold stress response remains largely unknown.Here,we reported that PHD17 negatively regulated cold tolerance in rice seedlings as a cleavage target of miR1320.PHD17 expression was greatly induced by cold stress,and was down-regulated by miR1320 overexpression and up-regulated by miR1320 knockdown.Through 5'RACE and dual luciferase assays,we found that miR1320 targeted and cleaved the 3'UTR region of PHD17.PHD17 was a nuclearlocalized protein and acted as a transcriptional activator in yeast.PHD17 overexpression reduced cold tolerance of rice seedlings,while knockout of PHD17 increased cold tolerance,partially via the CBF cold signaling.By combining transcriptomic and physiological analyses,we demonstrated that PHD17 modulated ROS homeostasis and flavonoid accumulation under cold stress.K-means clustering analysis revealed that differentially expressed genes in PHD17 transgenic lines were significantly enriched in the jasmonic acid(JA)biosynthesis pathway,and expression of JA biosynthesis and signaling genes was verified to be affected by PHD17.Cold stress tests applied with MeJA or IBU(JA synthesis inhibitor)further suggested the involvement of PHD17 in JA-mediated cold signaling.Taken together,our results suggest that PHD17 acts downstream of miR1320 and negatively regulates cold tolerance of rice seedlings through JA-mediated signaling pathway. 展开更多
关键词 RICE Cold tolerance PHD protein miR1320 JA signaling
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透骨消痛胶囊调控Nav1.7减轻膝骨关节炎小鼠软骨细胞退变
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作者 付长龙 林艳铭 +4 位作者 兰书洁 陈悦 李超 陆诗雨 林晴 《南方医科大学学报》 CAS CSCD 北大核心 2024年第11期2074-2081,共8页
目的从Nav1.7调控软骨细胞外基质稳态角度,研究透骨消痛胶囊对减轻膝骨关节炎(KOA)软骨细胞退变的作用机制。方法选择40只2月龄C57BL/6小鼠,通过随机数字表法将其分为空白组(n=10)和造模组(n=30)。造模组小鼠通过Hulth法手术建立KOA模型... 目的从Nav1.7调控软骨细胞外基质稳态角度,研究透骨消痛胶囊对减轻膝骨关节炎(KOA)软骨细胞退变的作用机制。方法选择40只2月龄C57BL/6小鼠,通过随机数字表法将其分为空白组(n=10)和造模组(n=30)。造模组小鼠通过Hulth法手术建立KOA模型后,随机分为模型组(生理盐水灌胃)、透骨消痛胶囊组(368 mg/kg剂量灌胃)、阳性药物组(10 mg/kg双氯芬酸钠灌胃),10只/组;空白组为生理盐水灌胃,干预6次/周,共4周。干预后5%异氟醚麻醉处死,获得膝关节软骨组织。形态学染色观察软骨组织结构变化,实时荧光定量PCR检测Nav1.7 mRNA水平,Western blotting分析Nav1.7、MMP-3、ADAMTS-5、COX-2蛋白表达变化。荧光原位杂交检测软骨细胞中Nav1.7的表达量。此外,利用慢病毒载体敲减Nav1.7(sh-Nav1.7)转染软骨细胞,实时荧光定量PCR分析转染后sh-Nav1.7在软骨细胞中mRNA水平变化。Western blotting分析在sh-Nav1.7条件下,透骨消痛胶囊对KOA软骨细胞MMP-3、MMP-13、ADAMTS-4、ADAMTS-5、COX-2蛋白的调控。结果形态学结果显示,和模型组对比,透骨消痛胶囊组和阳性药物组软骨层结构更完整,关节结构破坏程度减轻。透骨消痛胶囊组和阳性药物组的Nav1.7蛋白与mRNA水平降低(P<0.05),MMP-3、ADAMTS-5、COX-2蛋白表达减少(P<0.05)。荧光原位杂交结果显示,透骨消痛胶囊能降低IL-1β诱导的Nav1.7的荧光强度。在Nav1.7敲减实验中,与IL-1β组相比,IL-1β+sh-Nav1.7组中Nav1.7水平下降(P<0.05);与IL-1β+TGXTC组相比,IL-1β+sh-Nav1.7+TGXTC组中Nav1.7水平下降(P<0.05)。Western blotting结果表明,IL-1β组软骨细胞中升高的MMP-3、MMP-13、ADAMTS-4、ADAMTS-5、COX-2蛋白被透骨消痛胶囊干预后显著抑制(P<0.05),但在Nav1.7敲低后,透骨消痛胶囊对这些蛋白的调控作用减弱(P<0.05)。结论透骨消痛胶囊通过调控Nav1.7减轻KOA软骨细胞外基质代谢紊乱,从而发挥减轻软骨细胞退变的作用。 展开更多
关键词 透骨消痛胶囊 Nav1.7 软骨退变 膝骨关节炎
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Amitriptyline inhibits NLRP3 inflammasome activation via the ASM/CE pathway in a cell model of NAFLD 被引量:1
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作者 QIN LIU CHUNYAN NIU +3 位作者 QIANG ZHANG SHIQIN SUN yue chen YONGQIANG SHI 《BIOCELL》 SCIE 2024年第5期759-769,共11页
Background:Nonalcoholic fatty liver disease(NAFLD)is a global health concern with the acid sphingomyelinase(ASM)/ceramide(CE)pathway and the NOD-like receptor family,pyrin domain-containing protein 3(NLRP3)inflammasom... Background:Nonalcoholic fatty liver disease(NAFLD)is a global health concern with the acid sphingomyelinase(ASM)/ceramide(CE)pathway and the NOD-like receptor family,pyrin domain-containing protein 3(NLRP3)inflammasome identified as pivotal players in lipid disorders and inflammation.This study explores the interaction mechanism between the ASM/CE pathway and NLRP3 in NAFLD cell models,aiming to understand the impact of amitriptyline(Ami),an ASM inhibitor,on lipid deposition and hepatocyte injury by regulating the ASM/CE-NLRP3 pathway.Methods:HepG2 and HL-7702 cells were exposed to free fatty acids(FFAs)to establish the NAFLD model.The cells were divided into 5 groups:control group,model group,Ami group,tumor necrosis factoralpha(TNF-α)group,and Ami+TNF-αgroup.Intracellular lipid droplets were visualized using Oil Red O staining,and Western blot analysis quantified ASM,NLRP3,and caspase 1 protein expression.Enzyme linked immunosorbent assay(ELISA)was measured CE and ASM levels,while qRT-PCR assessed mRNA expression.The apoptotic rate was evaluated by flow cytometry(FCM).Results:Following FFAs incubation,significant increases in ASM and CE levels were observed in HepG2 and HL-7702 cells,accompanied by elevated expression of NLRP3,and caspase 1,and IL-1β.TNF-αtreatment further amplified these indicators.Ami demonstrated a reduction in lipid deposition,suppressed ASM/CE pathway activation,downregulated NLRP3 and caspase 1 expression,and improved apoptosis.Additionally,MCC950,a selective inhibitor of the NLRP3,mitigated NLRP3,caspase 1,and IL-1βexpression,alleviating lipid deposition and apoptosis in the NAFLD cell model.Conclusion:The ASM/CE-NLRP3 pathway in NAFLD cells promotes hepatocyte steatosis,inflammation,and cell damage.Ami emerges as a promising therapeutic agent by inhibiting the ASM/CE-NLRP3 pathway,underscoring its potential as a key target for NAFLD treatment. 展开更多
关键词 Nonalcoholic fatty liver disease HEPATOCYTE AMITRIPTYLINE ASM/CE pathway NLRP3 Nonalcoholic steatohepatitis
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Tree mycorrhizal associations determine how biodiversity,large trees,and environmental factors drive aboveground carbon stock in temperate forests
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作者 yue chen Zikun Mao +2 位作者 Jonathan A.Myers Jinghua Yu Xugao Wang 《Forest Ecosystems》 SCIE CSCD 2024年第4期448-456,共9页
Biodiversity,large trees,and environmental conditions such as climate and soil have important effects on forest carbon stocks.However,recent studies in temperate forests suggest that the relative importance of these f... Biodiversity,large trees,and environmental conditions such as climate and soil have important effects on forest carbon stocks.However,recent studies in temperate forests suggest that the relative importance of these factors depends on tree mycorrhizal associations,whereby large-tree effects may be driven by ectomycorrhizal(EM)trees,diversity effects may be driven by arbuscular mycorrhizal(AM)trees,and environment effects may depend on differential climate and soil preferences of AM and EM trees.To test this hypothesis,we used forest-inventory data consisting of over 80,000 trees from 631 temperate-forest plots(30 m×30 m)across Northeast China to examine how biodiversity(species diversity and ecological uniqueness),large trees(top 1%of tree diameters),and environmental factors(climate and soil nutrients)differently regulate aboveground carbon stocks of AM trees,EM trees,and AM and EM trees combined(i.e.total aboveground carbon stock).We found that large trees had a positive effect on both AM and EM tree carbon stocks.However,biodiversity and environmental factors had opposite effects on AM vs.EM tree carbon stocks.Specifically,the two components of biodiversity had positive effects on AM tree carbon stocks,but negative effects on EM tree carbon stocks.Environmental heterogeneity(mean annual temperature and soil nutrients)also exhibited contrasting effects on AM and EM tree carbon stocks.Consequently,for the total carbon stock,the positive large-tree effect far surpasses the diversity and environment effect.This is mainly because when integrating AM and EM tree carbon stock into total carbon stock,the opposite diversity-effect(also environment-effect)on AM vs.EM tree carbon stock counteracts each other while the consistent positive large-tree effect on AM and EM tree carbon stock is amplified.In summary,this study emphasized a mycorrhizal viewpoint to better understand the determinants of overarching aboveground carbon profile across regional forests. 展开更多
关键词 BIODIVERSITY Ecological uniqueness Environment heterogeneity Large trees Mycorrhizal associations Tree carbon stock
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Composition,function,and timing:exploring the early‑life gut microbiota in piglets for probiotic interventions
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作者 Jianping Quan Cineng Xu +14 位作者 Donglin Ruan Yong Ye Yibin Qiu Jie Wu Shenping Zhou Menghao Luan Xiang Zhao yue chen Danyang Lin Ying Sun Jifei Yang Enqin Zheng Gengyuan Cai Zhenfang Wu Jie Yang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第2期659-678,共20页
Background The establishment of a robust gut microbiota in piglets during their early developmental stage holds the potential for long-term advantageous effects.However,the optimal timeframe for introducing probiotics... Background The establishment of a robust gut microbiota in piglets during their early developmental stage holds the potential for long-term advantageous effects.However,the optimal timeframe for introducing probiotics to achieve this outcome remains uncertain.Results In the context of this investigation,we conducted a longitudinal assessment of the fecal microbiota of 63 piglets at three distinct pre-weaning time points.Simultaneously,we gathered vaginal and fecal samples from 23 sows.Employing 16S rRNA gene and metagenomic sequencing methodologies,we conducted a comprehensive analysis of the fluctuation patterns in microbial composition,functional capacity,interaction networks,and colonization resistance within the gut microbiota of piglets.As the piglets progressed in age,discernible modifications in intestinal microbial diversity,composition,and function were observed.A source-tracking analysis unveiled the pivotal role of fecal and vaginal microbiota derived from sows in populating the gut microbiota of neonatal piglets.By D21,the microbial interaction network displayed a more concise and efficient configuration,accompanied by enhanced colonization resistance relative to the other two time points.Moreover,we identified three strains of Ruminococcus sp.at D10 as potential candidates for improving piglets’weight gain during the weaning phase.Conclusions The findings of this study propose that D10 represents the most opportune juncture for the introduction of external probiotic interventions during the early stages of piglet development.This investigation augments our comprehension of the microbiota dynamics in early-life of piglets and offers valuable insights for guiding forthcoming probiotic interventions. 展开更多
关键词 Colonization resistance Intestinal microbiota PIGLET WEANING Weight gain
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Role of land-atmosphere coupling in persistent extreme climate events in eastern China in summer 2022
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作者 yue chen Aihui Wang 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第2期19-26,共8页
2022年暖季,中国东部地区遭受持续性高温,少雨和土壤干旱的复合极端事件.特征分析指出,在研究时段内,中国东部地区的气温,降水和土壤湿度呈现明显的季节内变化和南北差异。由1940-2022年的气候态可知,长江流域和东南地区的土壤含水充足... 2022年暖季,中国东部地区遭受持续性高温,少雨和土壤干旱的复合极端事件.特征分析指出,在研究时段内,中国东部地区的气温,降水和土壤湿度呈现明显的季节内变化和南北差异。由1940-2022年的气候态可知,长江流域和东南地区的土壤含水充足,蒸散主要受限于陆面有效能量.然而,潜在机制研究指出,2022年土壤湿度对蒸散的限制作用在上述区域异常偏强,土壤湿度与气候要素之间的强反馈可能在2022年复合极端事件的演变和持续中发挥了关键作用。 展开更多
关键词 复合极端事件 陆气耦合 土壤湿度 干旱 中国东部
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Degradation of FAK-targeting by proteolytic targeting chimera technology to inhibit the metastasis of hepatocellular carcinoma
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作者 XINFENG ZHANG SHUANG LI +8 位作者 MEIRU SONG yue chen LIANGZHENG CHANG ZHERUI LIU HONGYUAN DAI YUTAO WANG GANGQI YANG YUN JIANG YINYING LU 《Oncology Research》 SCIE 2024年第4期679-690,共12页
Liver cancer is a prevalent malignant cancer,ranking third in terms of mortality rate.Metastasis and recurrence primarily contribute to the high mortality rate of liver cancer.Hepatocellular carcinoma(HCC)has low expr... Liver cancer is a prevalent malignant cancer,ranking third in terms of mortality rate.Metastasis and recurrence primarily contribute to the high mortality rate of liver cancer.Hepatocellular carcinoma(HCC)has low expression of focal adhesion kinase(FAK),which increases the risk of metastasis and recurrence.Nevertheless,the efficacy of FAK phosphorylation inhibitors is currently limited.Thus,investigating the mechanisms by which FAK affects HCC metastasis to develop targeted therapies for FAK may present a novel strategy to inhibit HCC metastasis.This study examined the correlation between FAK expression and the prognosis of HCC.Additionally,we explored the impact of FAK degradation on HCC metastasis through wound healing experiments,transwell invasion experiments,and a xenograft tumor model.The expression of proteins related to epithelial-mesenchymal transition(EMT)was measured to elucidate the underlying mechanisms.The results showed that FAK PROTAC can degrade FAK,inhibit the migration and invasion of HCC cells in vitro,and notably decrease the lung metastasis of HCC in vivo.Increased expression of E-cadherin and decreased expression of vimentin indicated that EMT was inhibited.Consequently,degradation of FAK through FAK PROTAC effectively suppressed liver cancer metastasis,holding significant clinical implications for treating liver cancer and developing innovative anti-neoplastic drugs. 展开更多
关键词 Hepatocellular carcinoma(HCC) Focal adhesion kinase(FAK) Proteolytic targeting chimera technology(PROTAC) Epithelial-mesenchymal transformation(EMT) METASTASIS
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A dual-route optical emission spectroscopy diagnostic with wide spectral range and high wavelength resolution on HL-2A tokamak
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作者 陈越 高继昆 +10 位作者 龙婷 聂林 高金明 马尧 黄渊 田文静 刘延民 朱晓东 庄革 钟武律 许敏 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第3期25-30,共6页
A dual-route optical emission spectroscopy(D-OES)diagnostic is newly developed to monitor the optical emission from the X-point plasma region on the HL-2 A tokamak.This diagnostic is composed of an imaging system,a be... A dual-route optical emission spectroscopy(D-OES)diagnostic is newly developed to monitor the optical emission from the X-point plasma region on the HL-2 A tokamak.This diagnostic is composed of an imaging system,a beam-splitting system for dual-route measurements,fiber bundles,a spectrometer system,and a control and acquisition system.One route is used to obtain wide-spectral-range spectra,and the other route is used to acquire high-wavelengthresolution line shapes.The spectral resolution of the wide-range spectrometers is 0.8 nm with a coverage of 800 nm(@200-1000 nm).The spectral resolution of the high-resolution spectrometer is 0.01 nm with a coverage of 6 nm(@200-660 nm).The spatial resolution of each route of D-OES is about 4 cm with 11 channels.The temporal resolution is 16 ms at maximum in the single-channel mode.Wide-range spectra(containing Balmer series and a Fulcher band)and highly resolved Ha line shapes are obtained by D-OES in the hydrogen glow discharge in the lab.D-OES measurements are carried out in the high-density deuterium experiments of HL-2A.The electron density n_(e)and deuterium temperature T_(D) in the X-point multifaceted asymmetric radiation from the edge(MARFE)region are derived simultaneously by fitting the measured D_(a) shape.The density n_(e)is observed to increase from~8.7×10^(18)m^(-3)to~7.8×10^(19)m^(-3),and the temperature T_(D)drops from~14.4 eV to~2.3 eV after the onset of MARFE in the discharge#38260. 展开更多
关键词 optical emission spectroscopy Balmer series TOKAMAK
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Midpoint transverse process to pleura block for postoperative analgesia following laparoscopic renal cyst decortication:Two case reports
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作者 Wei-Jie He Wen-Xing Xu +4 位作者 Xu-Dong Zhang yue chen Shu-Ying He Xian-Qin Wei Xiao-Lan Huang 《World Journal of Clinical Cases》 SCIE 2024年第18期3629-3635,共7页
BACKGROUND The midpoint transverse process to pleura(MTP)block,a novel technique for thoracic paravertebral block(TPVB),was first employed in laparoscopic renal cyst decortication.CASE SUMMARY Thoracic paravertebral n... BACKGROUND The midpoint transverse process to pleura(MTP)block,a novel technique for thoracic paravertebral block(TPVB),was first employed in laparoscopic renal cyst decortication.CASE SUMMARY Thoracic paravertebral nerve block is frequently employed for perioperative analgesia during laparoscopic cyst decortication.To address safety concerns associated with TPVBs,we administered MTP blocks in two patients prior to administering general anesthesia for laparoscopic cyst decortication.The MTP block was performed at the T9 level under ultrasound guidance,with 20 mL of 0.5%ropivacaine injected.Reduced sensation to cold and pinprick was observed from the T8 to T11 dermatome levels.Immediately postoperative Numeric Pain Rating Scale scores were 0/10 at rest and on movement,with none exceeding a mean 24 h numeric rating scale>3.CONCLUSION MTP block was effective technique for providing postoperative analgesia for patients undergoing laparoscopic renal cyst decortication. 展开更多
关键词 Midpoint transverse process to pleura block Laparoscopic renal cyst decortication PAIN ANALGESIA Case report
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Study on improving hematopoietic function of rats with blood deficiency syndrome by Shengxuebao mixture
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作者 Yan Shu Hong-Na Liu +5 位作者 Yang Zhao Jin-Yi Cao yue chen Yi Qiao Hui Guo Zhi-Fu Yang 《Traditional Medicine Research》 2024年第8期35-46,共12页
Background:Shengxuebao mixture(SXBM)is a novel herbal drug approved by China State Food and Drug Administration for the treatment of Leukopenia and iron deficiency anemia caused by radiotherapy and chemotherapy.Method... Background:Shengxuebao mixture(SXBM)is a novel herbal drug approved by China State Food and Drug Administration for the treatment of Leukopenia and iron deficiency anemia caused by radiotherapy and chemotherapy.Methods:To explore the mechanism of SXBM in treating blood deficiency syndrome(BDS).Firstly,network pharmacology and in vivo experiments were used to screen candidate targets and important signaling pathways of SXBM,GO functional enrichment and KEGG pathway analysis were performed.Secondly,a BDS rat model was established to verify the results of the analysis of network pharmacological enrichment.Histopathology and routine peripheral blood examination were observed.The expressions of tumor necrosis factor-α,interleukin(IL)-6,HIF-1αand NF-κB were detected by Western blot,and the expressions of IL-6,IL-1βwere detected by ELISA.Results:62 bioactive components,66 potential targets and 131 signaling pathways of BDS were successfully identified by network pharmacology.Molecular docking simulation techniques showed that key targets tumor necrosis factor-α,IL-6,IL-1βcan dock well with crucial components,and the BDS-related signaling pathways HIF-1 and JAK-STAT play a vital role.The combined model experiment of acetylphenylhydrazine and cyclophosphamide showed that the model group had obvious blood deficiency,and the histopathology and blood routine were effectively restored after administration.Our findings indicate that SXBM’s therapeutic effect on BDS primarily involves the mediation of the HIF-1α/NF-κB signaling pathway and the regulation of hematopoietic factor expression.Conclusion:This study not only affirmed the protective properties of SXBM against BDS but also provided insights into a potential mechanism for blood replenishment in the treatment of BDS using SXBM. 展开更多
关键词 network pharmacology molecular docking technology blood deficiency syndrome hematopoietic factors HIF-1α/NF-κB
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离子液体镀铝工艺在纵向解锁机构弹簧上的应用研究
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作者 乐晨 张联英 +3 位作者 郭嘉 宋启良 张毅博 王明杰 《宇航材料工艺》 CAS CSCD 北大核心 2024年第2期112-118,共7页
纵向解锁机构是一套用于运载火箭整流罩两半罩连接与分离用的机构产品,其核心组件锁钩在验收和总装过程中需要重复多次解锁装配,弹簧是锁钩分离时使用的驱动元件。为提高弹簧可靠性,本文研究使用离子液体镀铝工艺替代含有氢脆隐患的电... 纵向解锁机构是一套用于运载火箭整流罩两半罩连接与分离用的机构产品,其核心组件锁钩在验收和总装过程中需要重复多次解锁装配,弹簧是锁钩分离时使用的驱动元件。为提高弹簧可靠性,本文研究使用离子液体镀铝工艺替代含有氢脆隐患的电镀锌进行表面处理。首先通过典型产品试镀形成工艺方法,随后进行弹簧试制,最后开展热环境和锁钩机构试验验证弹簧可靠性。结果表明,离子液体镀铝工艺中的喷丸工艺会导致弹簧力值略微下降;这种状态的弹簧能够满足环境适应性要求,重复解锁会造成弹簧镀层磨损,力值下降约5%,但仍满足设计要求。弹簧使用离子镀铝工艺表面处理能够替代电镀锌,工艺实施过程中的喷丸后处理需要严格控制,重复使用时对弹簧镀层和力值的影响需要关注。 展开更多
关键词 离子液体镀铝 纵向解锁机构 弹簧
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Leukopenia-a rare complication secondary to invasive liver abscess syndrome in a patient with diabetes mellitus:A case report
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作者 Chun-Yan Niu Bang-Tao Yao +4 位作者 Hua-Yi Tao Xin-Gui Peng Qing-Hua Zhang yue chen Lu Liu 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第10期3343-3349,共7页
BACKGROUND Thrombocytopenia is a common complication of invasive liver abscess syndrome(ILAS)by Klebsiella pneumoniae(K.pneumoniae)infection,which indicates severe infection and a poor prognosis.However,the presence o... BACKGROUND Thrombocytopenia is a common complication of invasive liver abscess syndrome(ILAS)by Klebsiella pneumoniae(K.pneumoniae)infection,which indicates severe infection and a poor prognosis.However,the presence of leukopenia is rare.There are rare reports on leukopenia and its clinical significance for ILAS,and there is currently no recognized treatment plan.Early and broad-spectrum antimi-crobial therapy may be an effective therapy for treating ILAS and improving its prognosis.CASE SUMMARY A 55-year-old male patient who developed fever,chills,and abdominal distension without an obvious cause presented to the hospital for treatment.Laboratory tests revealed thrombocytopenia,leukopenia,and multiple organ dysfunction.Imaging examinations revealed an abscess in the right lobe of the liver and thromboph-lebitis,and K.pneumoniae was detected in the blood cultures.Since the patient was diabetic and had multi-system involvement,he was diagnosed with ILAS accom-panied by leukopenia and thrombocytopenia.After antibiotic treatment and sys-temic supportive therapy,the symptoms disappeared,and the patient’s condition almost completely resolved.CONCLUSION Leukopenia is a rare complication of ILAS,which serves as an indicator of adverse prognostic outcomes and the severity of infection. 展开更多
关键词 Invasive liver abscess syndrome Klebsiella pneumoniae LEUKOPENIA THROMBOCYTOPENIA Treatment Prognosis Case report
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江西宁都县北部大地热流特征及地热资源成因机制 被引量:18
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作者 刘峰 王贵玲 +4 位作者 张薇 岳晨 甘浩男 肖则佑 欧小科 《地质通报》 CAS CSCD 北大核心 2020年第12期1883-1890,共8页
江西省宁都县北部地区地热资源丰富,但地热地质研究程度较低,制约着区域地热资源的研究与可持续发展。在前人研究基础上,依托中国地质调查工作,对研究区大地热流特征及地热成因机制进行分析。基于钻孔测温与热导率测试数据,分析校正得... 江西省宁都县北部地区地热资源丰富,但地热地质研究程度较低,制约着区域地热资源的研究与可持续发展。在前人研究基础上,依托中国地质调查工作,对研究区大地热流特征及地热成因机制进行分析。基于钻孔测温与热导率测试数据,分析校正得到区域内大地热流平均值为93.6 mW/m^2,远高于中国陆区平均值62.5 mW/m^2,区域热背景值较高。通过放射性测试可知本区大面积出露的花岗岩与混合岩放射性生热率平均值为6.47μW/m^3,属高放射性岩体,岩石的放射性衰变产热应是本区大地热流值较高的重要原因,幔源供热的基础上附加壳源产热,提供了稳定的热源。在此基础上,穿越本区的2条深大断裂及其次生断裂则为地下热水深循环提供了传热与导水通道。因此推测,研究区地热资源成因机制为“高热流与高产热花岗岩体生热+多级次断裂控热导水”的成因模式,该模式代表性较强,可为赣南地区地热找矿提供指导。 展开更多
关键词 赣南地区 大地热流 高产热花岗岩 地热成因模式
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福建省2010-2019年水资源生态足迹与生态承载力 被引量:15
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作者 岳晨 钱永 +3 位作者 崔向向 王春晓 刘峰 郭斯嘉 《水土保持通报》 CSCD 北大核心 2021年第6期282-287,共6页
[目的]对福建省水资源生态承载力进行研究,为该区水资源可持续利用提供科学依据。[方法]以水资源生态足迹作为理论基础,叠加水资源生态足迹三维模型,并以福建省2010—2019年数据为主,分析福建省水资源生态足迹、水资源生态承载力以及水... [目的]对福建省水资源生态承载力进行研究,为该区水资源可持续利用提供科学依据。[方法]以水资源生态足迹作为理论基础,叠加水资源生态足迹三维模型,并以福建省2010—2019年数据为主,分析福建省水资源生态足迹、水资源生态承载力以及水资源空间格局。[结果]福建省2010—2019年水资源生态足迹总体呈下降趋势,变化范围为0.696~0.928 hm^(2)/人;水资源生态承载力受降水影响,年际变幅较大,变化范围为2.602~10.944 hm^(2)/人,为水资源生态盈余。万元GDP水资源生态足迹呈现明显下降趋势;福建省西部地区水资源承载力明显好于东部沿海地区。水资源足迹深度为1,水资源足迹广度波动范围在1以下,并呈下降趋势。[结论]福建省水资源比较丰富。目前条件下,该省水资源承载力能够满足当地经济发展。但福建省水资源承载力年际变化较大,空间分布差异较大,随着经济的发展,水资源还是存在一定风险。 展开更多
关键词 水资源生态足迹 水资源生态承载力 水资源生态足迹深度 水资源生态足迹广度 福建省
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北京市2010-2019年水资源生态足迹和生态承载力 被引量:31
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作者 岳晨 刘峰 +2 位作者 杨柳 高昀 郭斯嘉 《水土保持通报》 CSCD 北大核心 2021年第3期291-295,304,共6页
[目的]定量评价北京市水资源生态承载状态,为地区可持续发展提供科学依据。[方法]以水资源生态足迹作为理论基础,叠加生态承载力模型,以北京市2010—2019年数据为主,分析了北京市水资源生态足迹、生态承载力和水资源负载指数的动态变化... [目的]定量评价北京市水资源生态承载状态,为地区可持续发展提供科学依据。[方法]以水资源生态足迹作为理论基础,叠加生态承载力模型,以北京市2010—2019年数据为主,分析了北京市水资源生态足迹、生态承载力和水资源负载指数的动态变化。[结果]北京市2010—2019年水资源生态足迹总趋势非常平稳,其值范围为0.28~0.32 hm^(2)/人。北京市人均水资源生态承载力在0.04~0.12 hm^(2)/人之间,受降水影响较大。但随着南水北调外来水的输入,该项指标受降水影响的程度有所降低。万元GDP水资源生态足迹呈现上下波动的趋势,整体变幅与北京市年均降水量变化趋势一致。北京市历年来水资源呈现明显赤字,负载指数也远高于10,水资源生态压力大。[结论]北京市近几年积极采取措施缓解水资源状况取得了一定成效,但目前北京市水资源形势依然比较严峻。南水北调外调水虽然从很大程度上缓解了北京市严重缺水的局面,但由于北京市水资源存量资本消耗严重,外来水对北京市水资源生态承载力的改善有限。提高水资源利用率,合理调整产业结构,依然是北京可持续发展的主要措施。 展开更多
关键词 水资源生态足迹 水资源生态承载力 水资源负载指数 北京市
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燕山中部大地热流及岩石圈热结构特征——以承德市七家-茅荆坝地热田为例 被引量:8
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作者 刘峰 王贵玲 +4 位作者 张薇 岳晨 陆川 黄起伟 欧小科 《地质学报》 EI CAS CSCD 北大核心 2020年第7期1950-1959,共10页
燕山中部地区地热资源丰富,地热地质条件较好,但该地区大地热流测量工作较少,岩石圈热结构研究尚未开展,制约了该地区的地热地质研究与资源勘探开发。本文以该地区的七家-茅荆坝地热田为典型区,结合地温测井、取样测试、数据收集与分析... 燕山中部地区地热资源丰富,地热地质条件较好,但该地区大地热流测量工作较少,岩石圈热结构研究尚未开展,制约了该地区的地热地质研究与资源勘探开发。本文以该地区的七家-茅荆坝地热田为典型区,结合地温测井、取样测试、数据收集与分析,初步查明燕山中部大地热流特征及浅部-深部岩层热物性特征,填补了大地热流值测量空白区,在此基础上建立了研究区热结构概念模型,估算其深部地温分布。研究得出燕山中部大地热流值变化较大,平均约57 mW/m^2,与周边温泉水温存在较好的相关关系。其中七家-茅荆坝地热田大地热流值较高,为74.9 mW/m^2。通过深部地温分布计算得出七家—茅荆坝地区居里面埋深为21.5~22.8 km,莫霍面温度约815℃,分析结果与前人研究成果较为一致,验证了本文所建立岩石圈热结构模型的准确性。 展开更多
关键词 燕山地区 七家-茅荆坝地热田 大地热流 岩石圈热结构 居里面
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肝藏血中肝郁血滞病机的实验探查 被引量:10
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作者 钱梦 岳晨 +3 位作者 杨宗纯 朱昊如 范方馨 谢鸣 《广州中医药大学学报》 CAS 2021年第7期1472-1480,共9页
【目的】探查肝藏血中肝郁血滞病机的现代内涵。【方法】将40只雄性大鼠随机分为正常组和模型组各20只。模型组采用慢性束缚应激法建立肝郁证模型,记录各组大鼠的不同时间点的外观行为与体质量的变化,于第2周末和第4周末进行糖水实验和... 【目的】探查肝藏血中肝郁血滞病机的现代内涵。【方法】将40只雄性大鼠随机分为正常组和模型组各20只。模型组采用慢性束缚应激法建立肝郁证模型,记录各组大鼠的不同时间点的外观行为与体质量的变化,于第2周末和第4周末进行糖水实验和旷场实验及检测下述指标水平:下丘脑去甲肾上腺素(NE);血浆5-羟色胺(5-HT)、皮质酮(CORT)、抗凝辅助因子抗凝血酶(AT-Ⅲ)、蛋白C(PC)及游离蛋白S(FPS);不同切变率下的全血黏度及血浆黏度,凝血酶原时间(PT)、活化部分凝血活酶时间(APTT)、凝血酶时间(TT)和纤维蛋白原(FIB),血小板聚集率。【结果】(1)肝郁相关指标。与正常组比较,模型组大鼠可见:体质量第1~4周均显著降低,活动状态和情绪睡眠积分均明显升高(P<0.05或P<0.01);糖水偏嗜度第2、4周均明显降低(P<0.05或P<0.01);爬行里程数第2周明显增加(P<0.01)、中央区停留时间明显降低(P<0.05),中央区停留时间、爬行里程数第4周均明显降低(P<0.05或P<0.01);血浆5-HT水平第2、4周均明显降低(P<0.05或P<0.01),血浆CORT水平第4周明显升高(P<0.05),下丘脑NE第4周水平明显降低(P<0.01)。(2)血滞相关指标。与正常组比较,模型组大鼠可见:第2周的PT、APTT、TT均明显降低(P<0.01),FIB明显升高(P<0.05),3 min血小板聚集率明显升高(P<0.01);第4周的中切、高切全血黏度和血浆黏度均明显升高(P<0.01),PT和APTT均明显降低(P<0.01),FIB明显升高(P<0.05),1、3、5 min血小板聚集率均明显升高(P<0.01),PC、FPS、AT-Ⅲ均明显降低(P<0.01)。【结论】慢性束缚应激肝郁证模型大鼠造模期间先后出现不同程度的肝郁证表现,而且还伴有血液黏度增高和凝血功能增强及肝脏对凝血因子及抗凝辅助因子平衡调节的异常。该结果在一定程度上可阐释中医肝郁血滞病机的现代内涵。 展开更多
关键词 肝郁证 肝郁血滞 神经内分泌 血液流变 凝血功能 动物模型 大鼠
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4种柳树叶片表面易去除与难去除颗粒物滞纳特征 被引量:4
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作者 张少伟 岳晨 +4 位作者 詹振枫 段劼 曹治国 刘俊祥 古琳 《林业科学》 EI CAS CSCD 北大核心 2020年第6期26-34,共9页
【目的】比较不同柳树叶片表面滞纳易去除和难去除颗粒物的质量及粒径分布差异,评价不同种柳树对颗粒物的滞纳特征,以期为进一步提高树木叶片滞纳大气颗粒物的定量评估精度及合理利用柳树进行城市绿化提供科学依据。【方法】以苗圃中3... 【目的】比较不同柳树叶片表面滞纳易去除和难去除颗粒物的质量及粒径分布差异,评价不同种柳树对颗粒物的滞纳特征,以期为进一步提高树木叶片滞纳大气颗粒物的定量评估精度及合理利用柳树进行城市绿化提供科学依据。【方法】以苗圃中3年生旱柳、龙爪柳、垂柳和蒿柳为研究对象,于雨后第7天(降雨量为36 mm)采集树叶样品,经泡洗得到易去除颗粒物,再对叶片进行刷洗和超声波清洗获得难去除颗粒物,称洗脱颗粒物干质量,测定粒径分布,计算易去除(ERP)、难去除(DRP)和总颗粒物(TRP)中各径级颗粒物质量和滞尘效率。【结果】不同柳树叶面的TRP和ERP滞纳量差异显著,其中ERP滞纳量占TRP滞纳量的比例为30%~50%;不同树种间,龙爪柳的ERP滞纳量最高,蒿柳的TRP和DRP滞纳量最高;在ERP和DRP不同粒径质量百分比方面,旱柳中粒径小于10μm颗粒物的比例均最高,蒿柳中10~100μm粒径颗粒物的比例最高;ERP的平均粒径大小排序为蒿柳(34.98μm)>龙爪柳(33.89μm)>垂柳(31.52μm)>旱柳(27.81μm),DRP的平均粒径大小排序为龙爪柳(40.18μm)>蒿柳(35.34μm)>垂柳(29.27μm)>旱柳(28.25μm);对于不同粒径颗粒物的绝对滞纳量,龙爪柳叶片对各径级ERP滞纳量均最高,蒿柳叶片对粒径大于10μm的DRP滞纳量最高,旱柳叶片对粒径小于10μm的DRP滞纳量均最高;蒿柳叶片对粒径大于10μm的TRP和DRP滞尘效率最高,旱柳叶片对粒径小于10μm的TRP和DRP滞尘效率最高,龙爪柳叶片对ERP的滞尘效率最高。【结论】4种柳树叶面难去除颗粒物滞纳量占50%以上。龙爪柳叶面滞纳的颗粒物更新最快,旱柳和垂柳叶面能持久固定小粒径颗粒物,蒿柳叶面对粒径大于10μm的颗粒物滞纳能力最强。 展开更多
关键词 大气颗粒物 粒径分布 滞尘能力 柳树
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天津市水资源生态足迹研究 被引量:8
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作者 岳晨 李凡 +4 位作者 付路路 宫志强 钱永 崔向向 王春晓 《水文》 CSCD 北大核心 2022年第6期56-60,共5页
以水资源生态足迹模型为基本结构,根据天津市2008—2019年数据,分析了天津市水资源生态足迹、生态承载力和水资源生态压力变化驱动因素。结果表明:天津市2008—2019年水资源生态足迹呈平稳波动。水资源常年处于生态赤字,最高为0.287 hm^... 以水资源生态足迹模型为基本结构,根据天津市2008—2019年数据,分析了天津市水资源生态足迹、生态承载力和水资源生态压力变化驱动因素。结果表明:天津市2008—2019年水资源生态足迹呈平稳波动。水资源常年处于生态赤字,最高为0.287 hm^(2)/人。天津市水资源生态足迹仍以农业用水为主,近几年呈明显降幅。天津市2008—2019年万元GDP水资源生态足迹呈波动性下降趋势。天津市历年水资源生态压力指数变化范围为4.284~21.442,远大于1,水资源开采处于非常不利的阶段。天津市常年依靠外调水缓解本地水资源供需矛盾,外调水的补充,对天津市的水资源生态承载力起到一定影响作用。 展开更多
关键词 水资源生态足迹 水资源生态承载力 水资源生态压力
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