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Transgenic expression of DwMYB2 impairs iron transport from root to shoot in Arabidopsis thaliana 被引量:8
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作者 yan-hong chen Xue-Min Wu +1 位作者 Hong-Qing Ling Wei-Cai Yang 《Cell Research》 SCIE CAS CSCD 2006年第10期830-840,共11页
在植物,铁举起和动态平衡紧被调整从土壤保证它的吸收并且在房间避免过量铁。涉及这个过程的许多基因在过去的几年期间被识别了,但是有在整个植物铁交通国王和分配的基因规定未解决的许多问题遗体。MYB 抄写因素包含约 50 氨基酸的双... 在植物,铁举起和动态平衡紧被调整从土壤保证它的吸收并且在房间避免过量铁。涉及这个过程的许多基因在过去的几年期间被识别了,但是有在整个植物铁交通国王和分配的基因规定未解决的许多问题遗体。MYB 抄写因素包含约 50 氨基酸的双人脚踏车重复 DNA 有约束力的主题(R) 并且涉及植物开发,荷尔蒙发信号和新陈代谢的许多方面的规定。这里,我们报导在 Arabidopsis thaliana 的兰花 R2R3-MYB 基因 DwMYB2 的宫外的表示授与转基因的植物超敏性熨缺乏。在 DwMYB2 转基因的植物,在根的铁内容在野类型的根与那相比更高是双重的,当颠倒在射击是真的时。在根和射击的铁内容的这不平衡建议到射击的从根的铁的 translocation 被 DwMYB2 的表示在转基因的植物影响。一致地,基因薄片和反向的抄写聚合酶链反应分析表明铁螯的 reductase 基因, AtFRO2,和铁 transporter 基因, AtIRT1 和 AtIRT2,当象 AtIREG1, AtFRD3 和 NRAMP1 那样的另外的潜在的铁运输 ers 是下面调整的时,由 DwMYB2 表示是起来调整的。另外, ers 和抄写因素也是的几通常认为的肽运输的表示在 35S::DwMYB2 改变了转基因的线。这些数据提供我们卓见进整个植物 translocation 尽管 heterologous 基因被表示,在植物为铁动态平衡熨并且识别候选人基因。 展开更多
关键词 拟南芥 铁吸收 铁平衡 铁转运 DwMYB2 转基因表达
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X-ray emission for Ar^(11+)ions impacting on various targets in the collisions near the Bohr velocity 被引量:2
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作者 周贤明 尉静 +7 位作者 程锐 陈燕红 梅策香 曾利霞 梁昌慧 李耀宗 赵永涛 张小安 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第8期312-316,共5页
X-ray emission from the collisions of 3 MeV Ar^(11+)ions with V,Fe,Co,Ni,Cu,and Zn is investigated.Both the x-rays of the target atom and projectile are observed simultaneously.The x-ray yield is extracted from the or... X-ray emission from the collisions of 3 MeV Ar^(11+)ions with V,Fe,Co,Ni,Cu,and Zn is investigated.Both the x-rays of the target atom and projectile are observed simultaneously.The x-ray yield is extracted from the original count.The inner-shell ionization cross section is estimated by the binary encounter approximation model and compared with the experimental result.The remarkable result is that the Ar K-shell x-ray yield is diminished with the target atomic number increasing,which is completely opposite to the theoretical calculation.That is interpreted by the competitive consumption of the energy loss for the ionization of inner-shell electrons between the projectile and target atom. 展开更多
关键词 ion-atom collision near Bohr velocity x-ray coulomb ionization
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Evaluation of the etiology and risk factors for maternal sepsis: A single center study in Guangzhou, China 被引量:2
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作者 Lin Lin Lu-Wen Ren +4 位作者 Xue-Yuan Li Wen Sun yan-hong chen Jing-Si chen Dun-Jin chen 《World Journal of Clinical Cases》 SCIE 2021年第26期7704-7716,共13页
BACKGROUND Maternal sepsis is a major cause of gestational morbidity and neonatal mortality worldwide and particularly in China.AIM To evaluate the etiology of maternal sepsis and further identify its risk factors.MET... BACKGROUND Maternal sepsis is a major cause of gestational morbidity and neonatal mortality worldwide and particularly in China.AIM To evaluate the etiology of maternal sepsis and further identify its risk factors.METHODS In this retrospective study,we evaluated 70698 obstetric patients who were admitted to the Third Affiliated Hospital of Guangzhou Medical University between January 1,2009 and June 30,2018.Subjects were divided into sepsis group and non-sepsis group based on the incidence of sepsis.Data about medical history(surgical and obstetric history)and demographic information were collected.The Mann-Whitney U test was used to compare patient age,gestational age and duration of hospitalization between the two groups.Univariate and multivariate logistic regression models were used to analyze the etiology and the risk factors for maternal sepsis.Unadjusted and adjusted odds ratios(OR)are reported.RESULTS A total of 561 of 70698 obstetric patients were diagnosed with infection;of the infected patients,492 had non-sepsis associated infection(87.7%),while 69 had sepsis(12.3%).The morbidity rate of maternal sepsis was 9.76/10000;the fatality rate in the sepsis group was 11.6%(8/69).Emergency admission(OR=2.183)or transfer(OR=2.870),irregular prenatal care(OR=2.953),labor induction(OR=4.665),cervical cerclage(OR=14.214),first trimester(OR=6.806)and second trimester(OR=2.09)were significant risk factors for maternal sepsis.CONCLUSION Mode of admission,poor prenatal care,labor induction,cervical cerclage,first trimester and second trimester pregnancy were risk factors for maternal sepsis.Escherichia coli was the most common causative organism for maternal sepsis,and the uterus was the most common site of infection. 展开更多
关键词 Maternal sepsis Sepsis-3 Infection Risk factors
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Nd L-shell x-ray emission induced by light ions
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作者 周贤明 尉静 +8 位作者 程锐 陈燕红 梅策香 曾利霞 柳钰 张艳宁 梁昌慧 赵永涛 张小安 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第6期310-315,共6页
The L-shell x-ray of Nd has been obtained for 300-600 keV He2+ions impacting,and compared with that produced by H+and H2+ions.The threshold of projectile kinetic energy for L-shell ionization of Nd is crudely verified... The L-shell x-ray of Nd has been obtained for 300-600 keV He2+ions impacting,and compared with that produced by H+and H2+ions.The threshold of projectile kinetic energy for L-shell ionization of Nd is crudely verified in the energy region of about 300-400 keV.It is found that the energy of the distinct L-subshell x-rays has a blue shift.The relative intensity ratios of Lβ_(1,3,4)and Lβ_(2,15)to Lα_(1,2)x-ray are enlarged compared to the atomic data,and they decrease with the increase of the incident energy,and increase with increasing the effective nuclear charge of the incident ions.That is interpreted by the multiple ionization of outer-shells induced by light ions. 展开更多
关键词 light ions ion-atom collision L-shell x-ray multiple ionization
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Predicting the CME arrival time based on the recommendation algorithm
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作者 石育榕 陈艳红 +9 位作者 刘四清 刘柱 王晶晶 崔延美 罗冰显 袁天娇 郑锋 王子思禹 何欣燃 李铭 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2021年第8期59-74,共16页
CME is one of the important events in the sun-earth system as it can induce geomagnetic disturbance and an associated space environment effect.It is of special significance to predict whether CME will reach the Earth ... CME is one of the important events in the sun-earth system as it can induce geomagnetic disturbance and an associated space environment effect.It is of special significance to predict whether CME will reach the Earth and when it will arrive.In this paper,we firstly built a new multiple association list for 215 different events with 18 characteristics including CME features,eruption region coordinates and solar wind parameters.Based on the CME list,we designed a novel model based on the principle of the recommendation algorithm to predict the arrival time of CMEs.According to the two commonly used calculation methods in the recommendation system,cosine distance and Euclidean distance,a controlled trial was carried out respectively.Every feature has been found to have its own appropriate weight.The error analysis indicates the result using the Euclidean distance similarity is much better than that using cosine distance similarity.The mean absolute error and root mean square error of test data in the Euclidean distance are 11.78 and 13.77 h,close to the average level of other CME models issued in the CME scoreboard,which verifies the effectiveness of the recommendation algorithm.This work gives a new endeavor using the recommendation algorithm,and is expected to induce other applications in space weather prediction. 展开更多
关键词 Sun:coronal mass ejections(CMEs) method:recommendation algorithm
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Superconducting and structural properties of the phosphorus-rich Nb_(2)P_(5) superconductor under high pressure
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作者 Lei-Ming chen Fang-Huang Wei +6 位作者 yan-hong chen Hang-Qi Liu Yang Xu Bo-Yu chen Can-Li Dai Yu-Bo Zhang Zhen-Hai Yu 《Tungsten》 EI CSCD 2023年第3期364-369,共6页
Nb_(2)P_(5) is a recently discovered Bardeen,Cooper,Schrieffer theory s-wave superconductor hosting nontrivial topological nodal-line structure,which could serve as an excellent platform for studying the interplay bet... Nb_(2)P_(5) is a recently discovered Bardeen,Cooper,Schrieffer theory s-wave superconductor hosting nontrivial topological nodal-line structure,which could serve as an excellent platform for studying the interplay between the superconductivity and nontrivial topological states.We report herein the superconducting and structural properties of Nb2P5studied by measuring the electrical resistivity and structure under high pressure up to ~28 GPa and performing first principles calculations.The superconducting transition temperature TCdecreases with applied pressure,and reaches a minimum of 1.9 K at ~20.0 GPa,followed by a continuous enhancement up to 50.0 GPa without saturation.Furthermore,at pressures above ~8.2 GPa,it is likely that a second superconducting transition appears and coexists with the initial one even up to~28 GPa.Theoretical calculations rule out the correlation between the second superconducting-like transition and structure.Moreover,the Nb2P5showed remarkable axial anisotropic compressibility,in which the b-axis is more compressible than the a-and c-axes.The variation of TCis discussed via considering the evolution of density of states around the Fermi level and the phonon spectrum. 展开更多
关键词 Phosphorus-rich superconductor Superconducting transition temperature High-pressure measurement First principles calculations
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Severe COVID-19-associated sepsis is different from classical sepsis induced by pulmonary infection with carbapenem-resistant klebsiella pneumonia (CrKP) 被引量:4
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作者 Ming Wu Zhi-Ye Zou +3 位作者 yan-hong chen Cong-LinWang Yong-Wen Feng Zhi-Feng Liu 《Chinese Journal of Traumatology》 CAS CSCD 2022年第1期17-24,共8页
Purpose::COVID-19 is also referred to as a typical viral septic pulmonary infection by 2019-nCoV.However,little is known regarding its characteristics in terms of systemic inflammation and organ injury,especially comp... Purpose::COVID-19 is also referred to as a typical viral septic pulmonary infection by 2019-nCoV.However,little is known regarding its characteristics in terms of systemic inflammation and organ injury,especially compared with classical bacterial sepsis.This article aims to investigate the clinical characteristics and prognosis between COVID-19-associated sepsis and classic bacterial-induced sepsis.Methods::In this retrospective cohort study,septic patients with COVID-19 in the intensive care unit(ICU)of a government-designed therapy center in Shenzhen,China between January 14,2020 and March 10,2020,and septic patients induced by carbapenem-resistant klebsiella pneumonia(CrKP)admitted to the ICU of the Second People's Hospital of Shenzhen,China between January 1,2014 and October 30,2019 were enrolled.Demographic and clinical parameters including comorbidities,critical illness scores,treatment,and laboratory data,as well as prognosis were compared between the two groups.Risk factors for mortality and survival rate were analyzed using multivariable logistic regression and survival curve,respectively.Results::A total of 107 patients with COVID-19 and 63 patients with CrKP were enrolled.A direct comparison between the two groups demonstrated more serious degrees of primary lung injury following 2019-nCoV infection(indicated by lower PaO 2/FiO 2),but milder systemic inflammatory response,lower sequential organ failure assessment score and better functions of the organs like heart,liver,kidney,coagulation,and circulation.However,the acquired immunosuppression presented in COVID-19 patients was more severe,which presented as lower lymphocyte counts(0.8×109/L vs.0.9×109/L).Moreover,the proportion of COVID-19 patients treated with corticosteroid therapy and extracorporeal membrane oxygenation was larger compared with CrKP patients(78.5%vs.38.1%and 6.5%vs.0,respectively)who required less invasive mechanical ventilation(31.6%vs.54.0%).The incidence of hospitalized mortality and length of ICU stay and total hospital stay were also lower or shorter in viral sepsis(12.1%vs.39.7%,6.5 days vs.23.0 days and 21.0 days vs.33.0 days,respectively)(all p<0.001).Similar results were obtained after being adjusted by age,gender,comorbidity and PaO2/FiO2.Lymphocytopenia and high acute physiology and chronic health evaluation II scores were common risk factors for in-hospital death.While the death cases of COVID-19 sepsis mostly occurred at the later stages of patients’hospital stay.Conclusion::Critical COVID-19 shares clinical characteristics with classical bacterial sepsis,but the degree of systemic inflammatory response,secondary organ damage and mortality rate are less severe.However,following 2019-nCoV infection,the level of immunosuppression may be increased and thus induce in more death at the later stage of patients’hospitalstay. 展开更多
关键词 Clinical characteristics IMMUNOSUPPRESSION MORTALITY COVID-19 Carbapenem-resistant klebsiella pneumonia(CrKP)
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Microstructure,mechanical properties and fracture behavior of a new WE43 alloy 被引量:2
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作者 Gui-Long Jia Li-Ping Wang +3 位作者 Yi-cheng Feng Er-Jun Guo yan-hong chen Chang-Liang Wang 《Rare Metals》 SCIE EI CAS CSCD 2021年第8期2197-2205,共9页
The microstructures,mechanical properties and fracture behaviors of a new WE43 alloy(Mg-4 Y-1.6 Nd-2 Sm-0.5 Zr)were investigated.The microstructure of the as-cast alloy includes a Mg matrix,Mg_(41)Sm_(5),Mg_(41)Nd_(5)... The microstructures,mechanical properties and fracture behaviors of a new WE43 alloy(Mg-4 Y-1.6 Nd-2 Sm-0.5 Zr)were investigated.The microstructure of the as-cast alloy includes a Mg matrix,Mg_(41)Sm_(5),Mg_(41)Nd_(5)and Mg_(24)Y_(5)eutectic phases,as well asβ-phase.After an optimal solution treatment,the eutectic phases are almost completely dissolved;only a few spots of blocky Mg-Y compounds remain at grain boundaries.After an aging treatment,a large amount ofβ’-phases are dispersed and precipitated at the grain interior,which provides good comprehensive mechanical properties of the alloy,particularly in the under-aged state.The tensile strength is up to290 MPa,the yield strength reaches 209 MPa,and the elongation is slightly improved.Furthermore,the fracture behaviors of the studied alloy in different states significantly differ.In addition,a comparison of mechanical properties of the new WE43,traditional WE43 and other modified WE43 alloys is presented. 展开更多
关键词 Mg-Y-Nd-Sm-Zr MICROSTRUCTURE Mechanical properties Fracture behavior Heat treatment
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Precision Surgery for Placenta Previa Complicated with Placenta Percreta 被引量:1
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作者 Juan-Juan chen Lin Yu +14 位作者 Chun-Hong Su Chun-Fang Zhang yan-hong chen Yan-Mei Zhou Wen-Jun He Fang He Ting Song Shou-Ping Wang Zhi-Yuan Su Qing-Ping Jiang Zi-Hao Zou Bin Yu Xiao-Ya Shen Xiao-Ming Guan Dun-Jin chen 《Maternal-Fetal Medicine》 2019年第1期18-24,共7页
Objectives:To investigate whether a precise circular resection of the uterine tissue at the placental attachment part is effective in cases with placenta previa complicated with placenta percreta (PPWPP).Methods:Patie... Objectives:To investigate whether a precise circular resection of the uterine tissue at the placental attachment part is effective in cases with placenta previa complicated with placenta percreta (PPWPP).Methods:Patients diagnosed with PPWPP were assessed for pregnancy termination at 34-36 weeks of gestation.During the operation,we performed circular resection of the uterine tissue at the placental attachment part.Then the characteristics of the operation and the follow-ups were recorded.Results:During the operation,the vital signs were stable.The mean intraoperative blood loss,packed red blood cells units transfusion,fresh frozen plasma transfusion,and operation time were 2140 mL,6 U,440 mL,and 179.8 minutes,respectively.There was no bowel,ureter,or bladder injury.And there was no patient transferred to the ICU after operation.The mean postoperative blood loss was 458.6mL.There was no fever,infection,intestinal obstruction,or other complications after operation during the hospitalization.The shape and the blood flow of the uterus were normal.After the patients were discharged,one had developed cesarean scar diverticulum.The mean lochia duration was 30 days.The menstrual cycle and volume were as before.The shape and the blood flow of the uterus and the ovarian were normal.Conclusions:The circular resection following end-to-end anastomosis is an effective precision surgical approach for PPWPP.It can achieve the purpose of hemostasis while maximizing the protection of organ function and reducing surgical trauma. 展开更多
关键词 Placenta previa Placenta percreta Precision surgery Circular resection
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