目的探讨自发性脑出血患者术后合并肺栓塞的危险因素,构建并验证列线图模型。方法本研究是回顾性队列研究,回顾性选取2015年1月至2023年1月于重庆医科大学附属第一医院及重庆大学附属三峡医院住院治疗的393例患者为训练组,165例患者为...目的探讨自发性脑出血患者术后合并肺栓塞的危险因素,构建并验证列线图模型。方法本研究是回顾性队列研究,回顾性选取2015年1月至2023年1月于重庆医科大学附属第一医院及重庆大学附属三峡医院住院治疗的393例患者为训练组,165例患者为验证组,采用单因素和多因素逐步Logistic回归分析,筛选出与自发性脑出血术后合并肺栓塞相关的危险因素,构建并验证基于这些因素的列线图模型。结果基于年龄、出血量、格拉斯哥昏迷评分(Glasgow coma scale,GCS)、手术方式、纤维蛋白(原)降解产物(fibrinogen degradation product,FDP)、D-二聚体、血红蛋白和血浆、渗透压、有无深静脉血栓等危险因素绘制列线图模型,受试者工作特征曲线(receiver operating characteristic curve,ROC)显示模型对是否存在肺栓塞区分度良好,曲线下面积(area under curve,AUC)=0.908,验证集的Hosmer-Lemeshow拟合优度检验表明此模型对于验证集的拟合度良好(χ^(2)=14.805,df=8,P=0.063),校正曲线与理想曲线较为接近,模型的预测概率与实际发生概率接近,说明该模型准确性较高,决策曲线分析显示在较大范围的阈值概率下,建立的列线图模型均可获得收益。结论本研究建立的自发性脑出血患者术后合并肺栓塞的预测模型具有良好的预测性能,可在临床工作中准确、及时、快速识别肺栓塞的发生。展开更多
Straw mulching is a widespread practice for reducing the soil carbon loss caused by erosion.However,the effects of straw mulching on dissolved organic matter(DOM)runoff loss from black soil are not well studied.How st...Straw mulching is a widespread practice for reducing the soil carbon loss caused by erosion.However,the effects of straw mulching on dissolved organic matter(DOM)runoff loss from black soil are not well studied.How straw mulching affects the composition and loss of runoff DOM by changing soil aggregates remains largely unclear.Here,a straw mulching treatment was compared to a no mulching treatment(as a control)on sloping farmland with black soil erosion in Northeast China.We divided the soil into large macroaggregates(>2 mm),small macroaggregates(0.25-2 mm),and microaggregates(<0.25 mm).After five rain events,the effects of straw mulching on the concentration(characterized by dissolved organic carbon(DoC)and composition(analyzed by fluorescence spectroscopy)of runoff and soil aggregate DOM were studied.The results showed that straw mulching reduced the runoff amount by 54.7%.Therefore,although straw mulching increased the average DOc concentration in runoff,it reduced the total runoff DOM loss by 48.3%.The composition of runoff DOM is similar to that of soil,as both contain humic-like acid and protein-like components.With straw mulching treatment,the protein-like components in small macroaggregates accumulated and the protein-like components in runoff declined with rain events.Fluorescence spectroscopy technology may help in understanding the hydrological paths of rain events by capturing the dynamic changes of runoff and soil DOM characteristics.A variation partitioning analysis(VPA)indicated that the DOM concentration and composition of microaggregates explained 68.2%of the change in runoff DOM from no mulching plots,while the change in runoff DOM from straw mulching plots was dominated by small macroaggregates at a rate of 55.1%.Taken together,our results demonstrated that straw mulching reduces the fragmentation of small macroaggregates and the loss of microaggregates,thus effecting DOM compositions in soil and reducing the DOM loss in runoff.These results provide a theoretical basis for reducing carbon loss in sloping farmland.展开更多
目的探讨术前有胶质瘤相关癫痫(glioma related epilepsy,GRE)病史的患者术后停药前动态脑电图(ambulatory electroencephalogram,AEEG)异常是否与癫痫复发相关。方法回顾性分析本院2014年1月至2020年6月68例行手术治疗且长期随访的GRE...目的探讨术前有胶质瘤相关癫痫(glioma related epilepsy,GRE)病史的患者术后停药前动态脑电图(ambulatory electroencephalogram,AEEG)异常是否与癫痫复发相关。方法回顾性分析本院2014年1月至2020年6月68例行手术治疗且长期随访的GRE患者AEEG及临床资料,根据停用抗癫痫药后是否出现癫痫复发,将病例分为发作组(停药后癫痫复发)和对照组(停药后无癫痫发作),分析两组棘尖波及阵发性慢波事件(paroxysmal slow wave events,PSWEs)出现率、数量差异。通过回顾性分析停药前AEEG显示有痫性放电的47例患者临床资料,探讨影响其癫痫预后的因素。结果(1)发作组31例患者停药前AEEG中有痫性放电者29例(93.5%),有PSWEs者11例(35.5%),对照组37例患者停药前AEEG中有痫性放电者18例(48.6%),有PSWEs者5例(13.5%)。发作组与对照组之间棘尖波及PSWEs出现率差异具有统计学意义(P<0.05)。(2)发作组棘尖波及慢波数量明显高于对照组,发作组主要以中大量棘尖波(25/29,86.2%)及大量阵发性慢波(8/11,72.7%)为主,对照组主要以少量棘尖波(14/18,77.8%)及少中量阵发性慢波(4/5,80.0%)为主。(3)伴有AEEG痫性放电时,肿瘤切除程度及肿瘤累及皮层与癫痫预后有关(P<0.05)。结论当肿瘤为次全切除或肿瘤累及皮质,同时停药前AEEG显示中量、大量棘尖波及PSWEs时,需考虑减缓停药,延长患者无发作间隔时间以降低癫痫复发风险。展开更多
目的:构建基于人工智能的高血压性脑出血医疗文本信息自动识别系统,快速识别和分析患者临床信息,高效地输出正确的诊疗方案。方法:基于国内外最新高血压性脑出血诊疗指南,经多位高年资神经外科医生和专业人工智能团队共同讨论,构建基于...目的:构建基于人工智能的高血压性脑出血医疗文本信息自动识别系统,快速识别和分析患者临床信息,高效地输出正确的诊疗方案。方法:基于国内外最新高血压性脑出血诊疗指南,经多位高年资神经外科医生和专业人工智能团队共同讨论,构建基于语言表征模型和专家模块的高血压性脑出血医疗文本信息自动识别及决策系统(即H系统)。随后将收集到的高血压性脑出血病例分为训练集、测试集和验证集,以数据库中病例的真实治疗方案为金标准,先总体评价H系统的准确性,再将其与神经外科医生进行对比,分析H系统的判读效率。结果:在测试集中,H系统所输出的治疗方案的准确率为94.0%(91.5%~96.5%),特异度为91.8%(86.3%~97.3%),灵敏度为95.5%(89.3%~98.2%),曲线下面积(area under the curve,AUC)值为0.936(0.922~0.950)(P=0.000);在验证集中,H系统所输出的治疗方案的准确率为93.3%(89.5%~97.1%),特异度为89.9%(83.4%~96.4%),灵敏度为95.8%(92.3%~99.3%),AUC值为0.928(0.891~0.966)(P=0.000)。在处理同样的70例病例时,H系统用时(334.60±4.46)s,而神经外科医生用时(12 550.28±95.45)s;在50 min内,H系统处理的病例数为(383±3)例,而神经外科医生处理的病例数为(11±4)例。结论:本研究所构建的H系统能够对高血压性脑出血患者的急诊病例进行自动识别和分析,并快速输出准确的诊疗方案,可协助医生对高血压脑出血进行急诊诊疗。展开更多
目的:研究载脂蛋白E基因(apolipoprotein E gene,APOE)多态性与面肌痉挛发病率是否存在关联。方法:收集重庆医科大学附属第一医院94例面肌痉挛患者(面肌组)和73例正常人(对照组)的临床资料,采用限制性片段长度多态性聚合酶链反应(cleave...目的:研究载脂蛋白E基因(apolipoprotein E gene,APOE)多态性与面肌痉挛发病率是否存在关联。方法:收集重庆医科大学附属第一医院94例面肌痉挛患者(面肌组)和73例正常人(对照组)的临床资料,采用限制性片段长度多态性聚合酶链反应(cleaved amplification polymorphism sequence-tagged sites,CAPs)检测所有人员的APOE基因型,分别计算出面肌组和对照组3种APOE等位基因,即APOEε2、APOEε3和APOEε4的分布情况,进行统计学分析其分布是否存在差异。结果:面肌组APOEε4等位基因频率为15.43%,明显高于对照组的6.85%;同时,面肌组的APOEε4等位基因携带者所占比例为29.79%,也明显高于对照组的13.70%,2组之间差异具有统计学意义(P=0.014)。结论:APOE基因多态性可能与面肌痉挛的发病率有关,其中APOEε4等位基因携带者可能更容易罹患面肌痉挛。展开更多
Single crystal rare-earth magnets,such as hexagonal-close-packed gadolinium,usually have a large second order anisotropy K2 and a negative first order anisotropy K1 at low temperatures,which are difficult to explain u...Single crystal rare-earth magnets,such as hexagonal-close-packed gadolinium,usually have a large second order anisotropy K2 and a negative first order anisotropy K1 at low temperatures,which are difficult to explain using microscopic theories.An atomic scale effective spin Hamiltonian F|{Si}|is proposed,which,apart from the usual isotropic nearest neighbor coupling J,consists of two new terms that are different for in-plane and out-of-plane neighbors and which are characterized by two new couplings C1 and C2,respectively.The hybrid Monte-Carlo method is utilized to sample this system to the desired Boltzmann-like distribution exp(-F/kBT).It is found that K2 and K1 are compatible with the experimental values and arise naturally from the exchange anisotropy C1 and C2,which are less than 0.01%in magnitude of the isotropic exchange energy J.This new model spin Hamiltonian can also be applied to study other magnetic properties.展开更多
文摘目的探讨自发性脑出血患者术后合并肺栓塞的危险因素,构建并验证列线图模型。方法本研究是回顾性队列研究,回顾性选取2015年1月至2023年1月于重庆医科大学附属第一医院及重庆大学附属三峡医院住院治疗的393例患者为训练组,165例患者为验证组,采用单因素和多因素逐步Logistic回归分析,筛选出与自发性脑出血术后合并肺栓塞相关的危险因素,构建并验证基于这些因素的列线图模型。结果基于年龄、出血量、格拉斯哥昏迷评分(Glasgow coma scale,GCS)、手术方式、纤维蛋白(原)降解产物(fibrinogen degradation product,FDP)、D-二聚体、血红蛋白和血浆、渗透压、有无深静脉血栓等危险因素绘制列线图模型,受试者工作特征曲线(receiver operating characteristic curve,ROC)显示模型对是否存在肺栓塞区分度良好,曲线下面积(area under curve,AUC)=0.908,验证集的Hosmer-Lemeshow拟合优度检验表明此模型对于验证集的拟合度良好(χ^(2)=14.805,df=8,P=0.063),校正曲线与理想曲线较为接近,模型的预测概率与实际发生概率接近,说明该模型准确性较高,决策曲线分析显示在较大范围的阈值概率下,建立的列线图模型均可获得收益。结论本研究建立的自发性脑出血患者术后合并肺栓塞的预测模型具有良好的预测性能,可在临床工作中准确、及时、快速识别肺栓塞的发生。
基金supported by the National Key Research and Development Project of China (2022YFD1601102)the Key R&D Plan of Heilongjiang Province, China (JD22B002)+1 种基金the Program on Industrial Technology System of National Soybean, China (CARS-04-PS17)the UNDP Project, China (cpr/21/401) and the National Natural Science Foundation of China (41771284)
文摘Straw mulching is a widespread practice for reducing the soil carbon loss caused by erosion.However,the effects of straw mulching on dissolved organic matter(DOM)runoff loss from black soil are not well studied.How straw mulching affects the composition and loss of runoff DOM by changing soil aggregates remains largely unclear.Here,a straw mulching treatment was compared to a no mulching treatment(as a control)on sloping farmland with black soil erosion in Northeast China.We divided the soil into large macroaggregates(>2 mm),small macroaggregates(0.25-2 mm),and microaggregates(<0.25 mm).After five rain events,the effects of straw mulching on the concentration(characterized by dissolved organic carbon(DoC)and composition(analyzed by fluorescence spectroscopy)of runoff and soil aggregate DOM were studied.The results showed that straw mulching reduced the runoff amount by 54.7%.Therefore,although straw mulching increased the average DOc concentration in runoff,it reduced the total runoff DOM loss by 48.3%.The composition of runoff DOM is similar to that of soil,as both contain humic-like acid and protein-like components.With straw mulching treatment,the protein-like components in small macroaggregates accumulated and the protein-like components in runoff declined with rain events.Fluorescence spectroscopy technology may help in understanding the hydrological paths of rain events by capturing the dynamic changes of runoff and soil DOM characteristics.A variation partitioning analysis(VPA)indicated that the DOM concentration and composition of microaggregates explained 68.2%of the change in runoff DOM from no mulching plots,while the change in runoff DOM from straw mulching plots was dominated by small macroaggregates at a rate of 55.1%.Taken together,our results demonstrated that straw mulching reduces the fragmentation of small macroaggregates and the loss of microaggregates,thus effecting DOM compositions in soil and reducing the DOM loss in runoff.These results provide a theoretical basis for reducing carbon loss in sloping farmland.
文摘目的:构建基于人工智能的高血压性脑出血医疗文本信息自动识别系统,快速识别和分析患者临床信息,高效地输出正确的诊疗方案。方法:基于国内外最新高血压性脑出血诊疗指南,经多位高年资神经外科医生和专业人工智能团队共同讨论,构建基于语言表征模型和专家模块的高血压性脑出血医疗文本信息自动识别及决策系统(即H系统)。随后将收集到的高血压性脑出血病例分为训练集、测试集和验证集,以数据库中病例的真实治疗方案为金标准,先总体评价H系统的准确性,再将其与神经外科医生进行对比,分析H系统的判读效率。结果:在测试集中,H系统所输出的治疗方案的准确率为94.0%(91.5%~96.5%),特异度为91.8%(86.3%~97.3%),灵敏度为95.5%(89.3%~98.2%),曲线下面积(area under the curve,AUC)值为0.936(0.922~0.950)(P=0.000);在验证集中,H系统所输出的治疗方案的准确率为93.3%(89.5%~97.1%),特异度为89.9%(83.4%~96.4%),灵敏度为95.8%(92.3%~99.3%),AUC值为0.928(0.891~0.966)(P=0.000)。在处理同样的70例病例时,H系统用时(334.60±4.46)s,而神经外科医生用时(12 550.28±95.45)s;在50 min内,H系统处理的病例数为(383±3)例,而神经外科医生处理的病例数为(11±4)例。结论:本研究所构建的H系统能够对高血压性脑出血患者的急诊病例进行自动识别和分析,并快速输出准确的诊疗方案,可协助医生对高血压脑出血进行急诊诊疗。
基金National Natural Science Foundation of China under Grant Nos.51771099 and 11621131001。
文摘Single crystal rare-earth magnets,such as hexagonal-close-packed gadolinium,usually have a large second order anisotropy K2 and a negative first order anisotropy K1 at low temperatures,which are difficult to explain using microscopic theories.An atomic scale effective spin Hamiltonian F|{Si}|is proposed,which,apart from the usual isotropic nearest neighbor coupling J,consists of two new terms that are different for in-plane and out-of-plane neighbors and which are characterized by two new couplings C1 and C2,respectively.The hybrid Monte-Carlo method is utilized to sample this system to the desired Boltzmann-like distribution exp(-F/kBT).It is found that K2 and K1 are compatible with the experimental values and arise naturally from the exchange anisotropy C1 and C2,which are less than 0.01%in magnitude of the isotropic exchange energy J.This new model spin Hamiltonian can also be applied to study other magnetic properties.
