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通过交叉验证堆栈和VAD信息检测Windows代码注入
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作者 翟继强 韩旭 +2 位作者 王家乾 孙海旭 杨海陆 《哈尔滨理工大学学报》 CAS 北大核心 2024年第2期43-51,共9页
Windows 32/64位代码注入攻击是恶意软件常用的攻击技术,在内存取证领域,现存的代码注入攻击检测技术在验证完整性方面不能处理动态内容,并且在解析内存中数据结构方面无法兼容不同版本的Windows系统。因此提出了通过交叉验证进程堆栈和... Windows 32/64位代码注入攻击是恶意软件常用的攻击技术,在内存取证领域,现存的代码注入攻击检测技术在验证完整性方面不能处理动态内容,并且在解析内存中数据结构方面无法兼容不同版本的Windows系统。因此提出了通过交叉验证进程堆栈和VAD信息定位注入代码方法,将基于遍历栈帧得到的函数返回地址、模块名等信息结合进程VAD结构来检测函数返回地址、匹配文件名以定位注入代码,并且研发了基于Volatility取证框架的Windows代码注入攻击检测插件codefind。测试结果表明,即使在VAD节点被恶意软件修改,方法仍能够有效定位Windows 32/64位注入代码攻击。 展开更多
关键词 vad 堆栈 Windows代码注入 内存取证技术
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脑蛋白水解物干预VaD小鼠海马神经元凋亡及可能的机制
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作者 王素平 武筱林 +3 位作者 王帅 宋涛 庄洁 兰小磊 《中华养生保健》 2024年第2期4-8,共5页
目的本研究旨在探讨脑蛋白水解物-I(CH-I)干预血管性痴呆(VaD)小鼠海马神经元凋亡的作用及可能的机制。方法通过Y迷宫从70只雄性昆明小鼠中筛选出学习能力较好的小鼠60只,随机选择10只为假手术组,其余50只建立VaD小鼠模型,随机分为模型... 目的本研究旨在探讨脑蛋白水解物-I(CH-I)干预血管性痴呆(VaD)小鼠海马神经元凋亡的作用及可能的机制。方法通过Y迷宫从70只雄性昆明小鼠中筛选出学习能力较好的小鼠60只,随机选择10只为假手术组,其余50只建立VaD小鼠模型,随机分为模型组,脑活素阳性药组,CH-I低、中、高剂量组[10、20、30 mg/(kg·d)体质量],连续给药4周。末次给药后,应用Y迷宫检测小鼠的学习记忆能力,采用HE染色观察小鼠海马区细胞的形态结构,TUNEL检测小鼠海马组织细胞凋亡,Western blot分析海马组织Akt、p-Akt、Bcl-2、Caspase-9(Casp-9)、Caspase-3(Casp-3)表达。结果脑蛋白水解物-I可改善VaD小鼠学习记忆能力,改善海马神经细胞的形态结构和凋亡,增强p-Akt、Bcl-2表达,同时抑制Casp-9和Casp-3表达。结论CH-I可能通过调节PI3K/Akt信号通路而抑制VaD小鼠海马神经细胞凋亡。 展开更多
关键词 脑蛋白水解物-I vad 海马 凋亡 PI3K/AKT 小鼠
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毒结清口服液联合VAD方案治疗多发性骨髓瘤疗效观察
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作者 许敏 曾清 +2 位作者 程纬民 李雪萍 何艾 《西部中医药》 2024年第3期147-150,共4页
目的:观察毒结清口服液联合VAD方案(长春新碱+阿霉素+地塞米松)治疗多发性骨髓瘤(multiple myeloma,MM)的临床疗效。方法:回顾性分析2015年3月至2020年3月于广西中医药大学第一附属医院治疗的82例MM患者的临床资料,依据治疗方案将患者... 目的:观察毒结清口服液联合VAD方案(长春新碱+阿霉素+地塞米松)治疗多发性骨髓瘤(multiple myeloma,MM)的临床疗效。方法:回顾性分析2015年3月至2020年3月于广西中医药大学第一附属医院治疗的82例MM患者的临床资料,依据治疗方案将患者分为联合组52例和对照组30例,对照组采用VAD方案化疗,联合组采用毒结清口服液联合VAD方案化疗。比较两组患者临床疗效、不良反应发生情况及治疗前后中医证候积分、肾功能指标和实验室指标。结果:两组临床疗效和不良反应总发生率比较,差异均无统计学意义(P>0.05);治疗后联合组中医证候积分、血肌酐(serum creatinine,SCr)、血尿素氮(blood urea nitrogen,BUN)、M蛋白、β2-微球蛋白(β2-microglobulin,β2-MG)、乳酸脱氢酶(lactate dehydrogenase,LDH)水平均低于对照组(P<0.05),血红蛋白(hemoglobin,Hb)水平高于对照组(P<0.05)。结论:毒结清口服液联合VAD方案可有效缓解MM患者临床症状,改善患者肾功能和Hb、M蛋白、β2-MG和LDH水平,且有一定安全性。 展开更多
关键词 多发性骨髓瘤 vad方案 毒结清口服液 临床疗效
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Increased retinal venule diameter as a prognostic indicator for recurrent cerebrovascular events:a prospective observational study 被引量:1
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作者 Ying Zhao Dawei Dong +5 位作者 Ding Yan Bing Yang Weirong Gui Man Ke Anding Xu Zefeng Tan 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第5期1156-1160,共5页
Microvasculature of the retina is considered an alternative marker of cerebral vascular risk in healthy populations.However,the ability of retinal vasculature changes,specifically focusing on retinal vessel diameter,t... Microvasculature of the retina is considered an alternative marker of cerebral vascular risk in healthy populations.However,the ability of retinal vasculature changes,specifically focusing on retinal vessel diameter,to predict the recurrence of cerebrovascular events in patients with ischemic stroke has not been determined comprehensively.While previous studies have shown a link between retinal vessel diameter and recurrent cerebrovascular events,they have not incorporated this information into a predictive model.Therefore,this study aimed to investigate the relationship between retinal vessel diameter and subsequent cerebrovascular events in patients with acute ischemic stroke.Additionally,we sought to establish a predictive model by combining retinal veessel diameter with traditional risk factors.We performed a prospective observational study of 141 patients with acute ischemic stroke who were admitted to the First Affiliated Hospital of Jinan University.All of these patients underwent digital retinal imaging within 72 hours of admission and were followed up for 3 years.We found that,after adjusting for related risk factors,patients with acute ischemic stroke with mean arteriolar diameter within 0.5-1.0 disc diameters of the disc margin(MAD_(0.5-1.0DD))of≥74.14μm and mean venular diameter within 0.5-1.0 disc diameters of the disc margin(MVD_(0.5-1.0DD))of≥83.91μm tended to experience recurrent cerebrovascular events.We established three multivariate Cox proportional hazard regression models:model 1 included traditional risk factors,model 2 added MAD_(0.5-1.0DD)to model 1,and model 3 added MVD0.5-1.0DD to model 1.Model 3 had the greatest potential to predict subsequent cerebrovascular events,followed by model 2,and finally model 1.These findings indicate that combining retinal venular or arteriolar diameter with traditional risk factors could improve the prediction of recurrent cerebrovascular events in patients with acute ischemic stroke,and that retinal imaging could be a useful and non-invasive method for identifying high-risk patients who require closer monitoring and more aggressive management. 展开更多
关键词 acute ischemic stroke arteriolar cerebrovascular events diameter digital retinal imaging MICROVASCULATURE prediction RECURRENT RETINA venular
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One-year results for myopia control of orthokeratology with different back optic zone diameters: a randomized trial using a novel multispectral-based topographer 被引量:1
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作者 Wen-Ting Tang Xiang-Ning Luo +4 位作者 Wen-Jing Zhao Jia Liao Xin-Yue Xu Hui-Dan Zhang Li Zhang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第2期324-330,共7页
AIM:To present the 1-year results of a prospective cohort study investigating the efficacy,potential mechanism,and safety of orthokeratology(ortho-k)with different back optic zone diameters(BOZD)for myopia control in ... AIM:To present the 1-year results of a prospective cohort study investigating the efficacy,potential mechanism,and safety of orthokeratology(ortho-k)with different back optic zone diameters(BOZD)for myopia control in children.METHODS:This randomized clinical study was performed between Dec.2020 and Dec.2021.Participants were randomly assigned to three groups wearing ortho-k:5 mm BOZD(5-MM group),5.5 mm BOZD(5.5-MM group),and 6 mm BOZD(6-MM group).The 1-year data were recorded,including axial length,relative peripheral refraction(RPR,measured by multispectral refractive topography,MRT),and visual quality.The contrast sensitivity(CS)was evaluated by CSV-1000 instrument with spatial frequencies of 3,6,12,and 18 cycles/degree(c/d);the corneal higher-order aberrations(HOAs)were measured by iTrace aberration analyzer.The one-way ANOVA was performed to assess the differences between the three groups.The correlation between the change in AL and RPR was calculated by Pearson’s correlation coefficient.RESULTS:The 1-year results of 20,21,and 21 subjects in the 5-MM,5.5-MM,and 6-MM groups,respectively,were presented.There were no statistical differences in baseline age,sex,or ocular parameters between the three groups(all P>0.05).At the 1-year visit,the 5-MM group had lower axial elongation than the 6-MM group(0.07±0.09 vs 0.18±0.11 mm,P=0.001).The 5-MM group had more myopic total RPR(TRPR,P=0.014),with RPR in the 15°–30°(RPR 15–30,P=0.015),30°–45°(RPR 30–45,P=0.011),temporal(RPR-T,P=0.008),and nasal area(RPR-N,P<0.001)than the 6-MM group.RPR 15–30 in the 5.5-MM group was more myopic than that in the 6-MM group(P=0.002),and RPR-N in the 5-MM group was more myopic than that in the 5.5-MM group(P<0.001).There were positive correlations between the axial elongation and the change in TRPR(r=0.756,P<0.001),RPR 15–30(r=0.364,P=0.004),RPR 30–45(r=0.306,P=0.016),and RPR-N(r=0.253,P=0.047).The CS decreased at 3 c/d(P<0.001),and the corneal HOAs increased in the 5-MM group(P=0.030).CONCLUSION:Ortho-k with 5 mm BOZD can control myopia progression more effectively.The mechanism may be associated with greater myopic shifts in RPR. 展开更多
关键词 relative peripheral refraction ORTHOKERATOLOGY MYOPIA back optic zone diameter axial length multispectral refractive topography
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基于梯度下降VAD方法的风场探测技术
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作者 胡文 贾豫东 《科技与创新》 2024年第6期42-44,共3页
为了获得高精度矢量风速,着重对激光雷达回波信号数据反演方法进行分析研究。开展了一系列1.55μm全光纤相干测风激光雷达测速实验,采用基于梯度下降的VAD(Velocity-Azimuth Display,速度方位显示)风场反演算法进行矢量风场的反演,并通... 为了获得高精度矢量风速,着重对激光雷达回波信号数据反演方法进行分析研究。开展了一系列1.55μm全光纤相干测风激光雷达测速实验,采用基于梯度下降的VAD(Velocity-Azimuth Display,速度方位显示)风场反演算法进行矢量风场的反演,并通过MATLAB编程与仿真进行分析。基于模拟数据进行仿真实验,以风场反演结果的均方误差(MSE)为评价指标,对比LM最小二乘算法、Newton-Gaussian(NG)最小二乘算法及梯度下降算法这3种风场反演算法在进行不同迭代次数下的均方误差。结果表明,梯度下降和LM最小二乘算法最终都能收敛且MSE值较小,但LM最小二乘算法受初值影响较大,所以选取梯度下降算法进行风场反演成为更优选择。 展开更多
关键词 梯度下降 全光纤相干测风激光雷达 vad风场反演 均方误差分析
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On Spanning Wide Diameter of Graphs
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作者 WANG Yameng YIMINGJIANG Shabier 《新疆大学学报(自然科学版中英文)》 CAS 2024年第5期571-578,590,共9页
A t-container Ct(u,v)is a set of t internally disjoint paths between two distinct vertices u and v in a graph G,i.e.,Ct(u,v)={P_(1),P_(2),···,Pt}.Moreover,if V(P_(1))∪V(P_(2))∪···∪V(Pt... A t-container Ct(u,v)is a set of t internally disjoint paths between two distinct vertices u and v in a graph G,i.e.,Ct(u,v)={P_(1),P_(2),···,Pt}.Moreover,if V(P_(1))∪V(P_(2))∪···∪V(Pt)=V(G)then Ct(u,v)is called a spanning t-container,denoted by C_(t)^(sc)(u,v).The length of C_(t)^(sc)(u,v)={P_(1),P_(2),···,Pt}is l(C_(t)^(sc)(u,v))=max{l(P_(i))|1≤i≤t}.A graph G is spanning t-connected if there exists a spanning t-container between any two distinct vertices u and v in G.Assume that u and v are two distinct vertices in a spanning t-connected graph G.Let D_(t)^(sc)(u,v)be the collection of all C_(t)^(sc)(u,v)’s.Define the spanning t-wide distance between u and v in G,d_(t)^(sc)(u,v)=min{l(C_(t)^(sc)(u,v))|C_(t)^(sc)(u,v)∈D_(t)^(sc)(u,v)},and the spanning t-wide diameter of G,D_(t)^(sc)(G)=max{d_(t)^(sc)(u,v)|u,v∈V(G)}.In particular,the spanning wide diameter of G is D_(κ)^(sc)(G),whereκis the connectivity of G.In the paper we provide the upper and lower bounds of the spanning wide diameter of a graph,and show that the bounds are best possible.We also determine the exact values of wide diameters of some well known graphs including Harary graphs and generalized Petersen graphs et al.. 展开更多
关键词 CONNECTIVITY spanning connectivity spanning laceability wide diameter spanning wide diameter
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Effect of a cervical collar on optic nerve sheath diameter in trauma patients
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作者 Mümin Murat Yazici Ozcan Yavasi 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2024年第2期126-130,共5页
BACKGROUND:As advocated in advanced trauma life support and prehospital trauma life support protocols,cervical immobilization is applied until cervical spine injury is excluded.This study aimed to show the difference ... BACKGROUND:As advocated in advanced trauma life support and prehospital trauma life support protocols,cervical immobilization is applied until cervical spine injury is excluded.This study aimed to show the difference in optic nerve sheath diameter(ONSD)between patients with and without a cervical collar using computed tomography(CT).METHODS:This was a single-center,retrospective study examining trauma patients who presented to the emergency department between January 1,2021,and December 31,2021.The ONSD on brain CT of the trauma patients was measured and analyzed to determine whether there was a difference between the ONSD with and without the cervical collar.RESULTS:The study population consisted of 169 patients.On CT imaging of patients with(n=66)and without(n=103)cervical collars,the mean ONSD in the axial plane were 5.43±0.50 mm and 5.04±0.46 mm respectively for the right eye and 5.50±0.52 mm and 5.11±0.46 mm respectively for the left eye.The results revealed an association between the presence of a cervical collar and the mean ONSD,which was statistically significant(P<0.001)for both the right and left eyes.CONCLUSION:A cervical collar may be associated with increased ONSD.The effect of this increase in the ONSD on clinical outcomes needs to be investigated,and the actual need for cervical collar in the emergency department should be evaluated on a case-by-case basis. 展开更多
关键词 Optic nerve sheath diameter Computed tomography TRAUMA Emergency medicine
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Added value of ratio of cross diameters of the appendix in ultrasound diagnosis of acute appendicitis
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作者 Feng-Wa Gu Si-Ze Wu 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第1期21-28,共8页
BACKGROUND The maximum outer diameter(MOD)of the appendix is an essential parameter for diagnosing acute appendicitis,but there is space for improvement in ultrasound(US)diagnostic performance.AIM To investigate wheth... BACKGROUND The maximum outer diameter(MOD)of the appendix is an essential parameter for diagnosing acute appendicitis,but there is space for improvement in ultrasound(US)diagnostic performance.AIM To investigate whether combining the ratio of the cross diameters(RATIO)of the appendix with MOD of the appendix can enhance the diagnostic performance of acute appendicitis.METHODS A retrospective study was conducted,and medical records of 233 patients with acute appendicitis and 112 patients with a normal appendix were reviewed.The MOD and RATIO of the appendix were calculated and tested for their diagnostic performance of acute appendicitis,both individually and in combination.RESULTS The RATIO for a normal appendix was 1.32±0.16,while for acute appendicitis it was 1.09±0.07.The cut-off value for RATIO was determined to be≤1.18.The area under the receiver operating characteristic curve(AUC)for diagnosing acute appendicitis using RATIO≤1.18 and MOD>6 mm was 0.870 and 0.652,respectively.There was a significant difference in AUC between RATIO≤1.18 and MOD>6 mm(P<0.0001).When comparing the combination of RATIO≤1.18 and MOD>6 mm with MOD>6 mm alone,the combination showed increased specificity,positive predictive value(PPV),and AUC.However,the sensitivity and negative predictive value decreased.CONCLUSION Combining RATIO of the appendix≤1.18 and MOD>6 mm can significantly improve the specificity,PPV,and AUC in the US diagnosis of acute appendicitis. 展开更多
关键词 Acute appendicitis diameter RATIO Diagnosis ULTRASOUND
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Simulation of Haloxylon Ammodendron Stand Basic Diameter Structure Based on Fuzzy Distribution Function
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作者 Shaohua Wang Chuanqiang Liu Ting Yang 《Agricultural Sciences》 2024年第1期132-145,共14页
Based on the investigation data of 12 Haloxylon ammodendron plots in the south edge of Gurbantunggut Desert, Fuzzy distribution was introduced into the study of Haloxylon ammodendron base diameter structure fitting ac... Based on the investigation data of 12 Haloxylon ammodendron plots in the south edge of Gurbantunggut Desert, Fuzzy distribution was introduced into the study of Haloxylon ammodendron base diameter structure fitting according to the consistency between the characteristics of Fuzzy distribution function and the distribution series of cumulative percentage of stand base diameter, and the fitting precision and effect of Fuzzy distribution function were discussed. The root mean square error RMSE and determination coefficient R<sup>2</sup> values showed that Fuzzy-Γ<sub>1</sub>, Fuzzy-Γ<sub>2</sub>, Fuzzy-Γ<sub>3</sub>, Fuzzy-Γ<sub>4</sub> had good fitting performance, among which Fuzzy-Γ<sub>1</sub> had relatively high fitting precision, and its parameters were closely related to stand age and density, Fuzzy-Γ<sub>2</sub> distribution function was the second, and Fuzzy-Γ<sub>4</sub> distribution function had the worst fitting effect. By introducing a parameter c from the similarity of four distribution function formulas, a generalized Fuzzy distribution function Fuzzy-Γ<sub>5</sub> is obtained. This function shows the highest fitting accuracy. Most of the values of parameter c are near 1 or 2, which shows that the diameter distribution is mainly approximate to Fuzzy-Γ<sub>1</sub> and Fuzzy-Γ<sub>2</sub>. 展开更多
关键词 Fuzzy Distribution Function Haloxylon Ammodendron Base diameter Distribution Stand Factor
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An evaluation of ureteral diameter ratio and vesicoureteral reflux index in the treatment of primary vesicoureteral reflux
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作者 Yusuf Atakan Baltrak Nebil Akdogan +3 位作者 Mutlu Deger Volkan Izol Ibrahim Atilla Aridogan Nihat Satar 《Asian Journal of Urology》 CSCD 2024年第3期437-442,共6页
Objective:Vesicoureteral reflux(VUR)index is a simple,validated tool that reliably predicts significant improvement and spontaneous resolution of primary reflux in children.The aim of this study was to evaluate and co... Objective:Vesicoureteral reflux(VUR)index is a simple,validated tool that reliably predicts significant improvement and spontaneous resolution of primary reflux in children.The aim of this study was to evaluate and compare the ureter diameter ratio(UDR)and VUR index(VURx)of patients treated with endoscopic injection(EI)and ureteroneocystostomy(UNC)methods in the pediatric age group due to primary VUR.Methods:Patients under the age of 18 years old who underwent EI and UNC with the diagnosis of primary VUR between January 2011 and September 2021 were determined as the participants.The UDR was assessed using voiding cystourethrography,and the VURx score was determined prior to treatment based on hospital records included in the study.Results:A total of 255 patients,60(23.5%)boys and 195(76.5%)girls,with a mean age of 76.5(range 13.0e204.0)months,were included in the study.EI was applied to 130(51.0%)patients and UNC was applied to 125(49.0%)patients due to primary VUR.The optimum cut-off for the distal UDR was obtained as 0.17 with sensitivity and specificity of 73.0%and 63.0%,respectively.The positive and negative predictive values were 66.0%and 70.0%,respectively.Conclusion:When the UDR and VURx score are evaluated together for the surgical treatment of primary VUR in the pediatric age group,it is thought that it may be useful in predicting the clinical course of the disease and evaluating surgical treatment options. 展开更多
关键词 Distal ureter diameter ratio Vesicoureteral reflux Vesicoureteral reflux index management Vesicoureteral reflux index
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Platelet counts to spleen diameter ratio:A promising noninvasive tool for predicting esophageal varices in cirrhosis patients
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作者 Getnet Yigzaw Mossie Abdulsemed Mohammed Nur +2 位作者 Zekarias Seifu Ayalew Gebeyehu Tessema Azibte Kaleb Assefa Berhane 《World Journal of Hepatology》 2024年第10期1177-1187,共11页
BACKGROUND Liver cirrhosis is the end stage of progressive liver fibrosis as a consequence of chronic liver inflammation,wherein the standard hepatic architecture is replaced by regenerative hepatic nodules,which even... BACKGROUND Liver cirrhosis is the end stage of progressive liver fibrosis as a consequence of chronic liver inflammation,wherein the standard hepatic architecture is replaced by regenerative hepatic nodules,which eventually lead to liver failure.Cirrhosis without any symptoms is referred to as compensated cirrhosis.Complications such as ascites,variceal bleeding,and hepatic encephalopathy indicate the onset of decompensated cirrhosis.Gastroesophageal varices are the hallmark of clini-cally significant portal hypertension.AIM To determine the accuracy of the platelet count-to-spleen diameter(PC/SD)ratio to evaluate esophageal varices(EV)in patients with cirrhosis.METHODS This retrospective observational study was conducted at Tikur Anbessa Specia-lized Hospital and Adera Medical Center from January 1,2019,to December 30,2023.Data were collected via chart review and direct patient interviews using structured questionnaires.The data were exported to the SPSS software version 26 for analysis and clearance.A receiver operating characteristic curve was plotted for splenic diameter,platelet count,and PC/SD ratio to obtain sensitivity,speci-ficity,positive predictive value,negative predictive value,positive likelihood ratio,and negative likelihood ratio.RESULTS Of the 140 participants,67%were men.Hepatitis B(38%)was the most common cause of cirrhosis,followed by cryptogenic cirrhosis(28%)and hepatitis C(16%).Approximately 83.6%of the participants had endoscopic evidence of EV,whereas 51.1%had gastric varices.Decompensated cirrhosis and PC were associated with the presence of EV with adjusted odds ratios of 12.63(95%CI:3.16-67.58,P=0.001)and 0.14(95%CI:0.037-0.52,P=0.004),respectively.A PC/SD ratio<1119 had a sensitivity of 86.32%and specificity of 70%with area under the curve of 0.835(95%CI:0.736-0.934,P<0.001).CONCLUSION A PC/SD ratio<1119 predicts EV in patients with cirrhosis.It is a valuable,noninvasive tool for EV risk assess-ment in resource-limited settings. 展开更多
关键词 Cirrhosis Esophageal varices Portal hypertension Platelet count Splenic diameter
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Study of the Characteristics of Large-Diameter Iron Bars Obtained by Rolling at the ODHAV Foundry in the Republic of Guinea
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作者 Alpha Issa Diallo Jean Ahmadou Kourouma +3 位作者 Adama Moussa Sakho Younoussa Moussa Baldé Mamadou Madaniou Sow Alexandre Lucien Richard 《Journal of Materials Science and Chemical Engineering》 2024年第6期43-54,共12页
This work consists of evaluating the quality of the mechanical parameters of large-diameter steels, i.e. 20, 25, 28 and 32, through a process of recycling scrap metal that fills garages, rubbish dumps, gutters and oth... This work consists of evaluating the quality of the mechanical parameters of large-diameter steels, i.e. 20, 25, 28 and 32, through a process of recycling scrap metal that fills garages, rubbish dumps, gutters and other abandoned sites, as well as imported concrete reinforcing steel sold in the Republic of Guinea. To carry out this important work, a number of mechanical tensile and bending tests and a microscopic analysis combining two devices, an electron microscope and a photographic camera, were carried out. The samples were taken from sampling areas in the major communes of Conakry, namely: Casse Sonfonia, Matoto and Kagbélen. The tensile strength values of the large dimensions 20, 25, 28 and 32 are given in the tables. 展开更多
关键词 Recycled Scrap Large diameter ROLLING Tensile Testing BENDING
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Optic nerve sheath diameters in nontraumatic brain injury:A scoping review and role in the intensive care unit
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作者 Madhura Bhide Deven Juneja +1 位作者 Omender Singh Shakya Mohanty 《World Journal of Critical Care Medicine》 2024年第3期75-90,共16页
BACKGROUND Neuromonitoring in medical intensive care units is challenging as most patients are unfit for invasive intracranial pressure(ICP)modalities or unstable to transport for imaging.Ultrasonography-based optic n... BACKGROUND Neuromonitoring in medical intensive care units is challenging as most patients are unfit for invasive intracranial pressure(ICP)modalities or unstable to transport for imaging.Ultrasonography-based optic nerve sheath diameter(ONSD)is an attractive option as it is reliable,repeatable and easily performed at the bedside.It has been sufficiently validated in traumatic brain injury(TBI)to be incorporated into the guidelines.However,currently the data for non-TBI patients is inconsistent for a scientific recommendation to be made.AIM To compile the existing evidence for understanding the scope of ONSD in measuring ICP in adult non-traumatic neuro-critical patients.METHODS PubMed,Google Scholar and research citation analysis databases were searched for studies in adult patients with non-traumatic causes of raised ICP.Studies from 2010 to 2024 in English languages were included.RESULTS We found 37 articles relevant to our search.The cutoff for ONSD in predicting ICP varied from 4.1 to 6.3 mm.Most of the articles used cerebrospinal fluid opening pressure followed by raised ICP on computed tomography/magnetic resonance imaging as the comparator parameter.ONSD was also found to be a reliable outcome measure in cases of acute ischaemic stroke,intracerebral bleeding and intracranial infection.However,ONSD is of doubtful utility in septic metabolic encephalopathy,dysnatremias and aneurysmal subarachnoid haemorrhage.CONCLUSION ONSD is a useful tool for the diagnosis of raised ICP in non-traumatic neuro-critically ill patients and may also have a role in the prognostication of a subset of patients. 展开更多
关键词 Intracranial hypertension Intracranial pressure monitoring Medical intensive care unit Neuro-monitoring Nontraumatic brain injury Optic nerve sheath diameter Optic nerve ultrasound
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硼替佐米联合地塞米松和沙利度胺与VAD化疗方案治疗多发性骨髓瘤的临床疗效比较
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作者 栾静 化静 马丛丛 《当代医学》 2023年第12期40-43,共4页
目的比较硼替佐米联合地塞米松和沙利度胺与VAD化疗方案治疗多发性骨髓瘤的临床疗效。方法选取2017年5月至2020年5月本院收治的110例多发性骨髓瘤患者作为研究对象,采取随机数字表法分为观察组与对照组,各55例。对照组行VAD化疗方案,观... 目的比较硼替佐米联合地塞米松和沙利度胺与VAD化疗方案治疗多发性骨髓瘤的临床疗效。方法选取2017年5月至2020年5月本院收治的110例多发性骨髓瘤患者作为研究对象,采取随机数字表法分为观察组与对照组,各55例。对照组行VAD化疗方案,观察组行硼替佐米+地塞米松+沙利度胺联合化疗,比较两组临床疗效、治疗前后M蛋白、β2-微球蛋白、浆细胞、血钙、血红蛋白水平及不良反应发生率。结果观察组治疗总有效率为81.82%,高于对照组的61.82%,差异有统计学意义(P<0.05)。治疗前,两组M蛋白、β2-微球蛋白、浆细胞水平比较差异无统计学意义;治疗后,两组M蛋白、β2-微球蛋白水平均低于治疗前,且观察组均低于对照组,观察组浆细胞水平低于治疗前,且低于对照组,差异有统计学意义(P<0.05);对照组治疗前后浆细胞水平比较差异无统计学意义。两组治疗前后组内、组间血钙及血红蛋白水平比较差异均无统计学意义。观察组不良反应发生率为9.09%,低于对照组的23.64%,差异有统计学意义(P<0.05)。结论与VAD治疗方案相比,硼替佐米联合地塞米松与沙利度胺治疗多发性骨髓瘤可获得更好的临床效果,安全性更高。 展开更多
关键词 硼替佐米 地塞米松 沙利度胺 vad 多发性骨髓瘤
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Sub-stand diameter distribution types vary along an old-growth Douglas-fir chronosequence into the horizontal diversification development stage 被引量:1
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作者 JeriLynn E.Peck Eric K.Zenner 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第2期415-424,共10页
Managing mature Douglas-fir[Pseudotsuga menziesii(Mirb.)Franco]stands to emulate the structural complexity of natural old-growth forest requires identifying structural targets at the sub-stand level at which neighborh... Managing mature Douglas-fir[Pseudotsuga menziesii(Mirb.)Franco]stands to emulate the structural complexity of natural old-growth forest requires identifying structural targets at the sub-stand level at which neighborhood dynamics and patchy disturbance shape structure.We therefore sought to describe the archetypal shapes of predominant sub-stand diameter distribution types(DDTs)observed in natural tree neighborhoods in stands comprising a chronosequence(ca.120-450+yrs)encompassing mature,vertical diversification,and horizontal diversification development stages.The ten 1.0 ha stands are located in the southcentral Oregon Cascades,USA.Building on the known spatial position of each tree,natural tree neighborhoods were identified using the floating neighborhood approach based on spatial tessellation connecting neighboring trees at the first-(mean 61 m2)through fifth-(mean 2058 m2)order scales.Cluster analysis was then used to objectively identify the most predominant DDTs among the relative tree size distributions observed in the trans-scale neighborhoods within each stand.Repeated measures regression was used to classify each DDT to one of six observed archetypal shapes:negative exponential,unimodal,rotated sigmoid,bimodal,concave,or multi-modal.Only three of the 81 observed DDTs deviated by<10%from the stand average,while every stand had at least one DDT that deviated by>50%(maximum 83%).Within each stand,five to ten predominant DDTs were observed,which deviated from the stand average by 30-48%and were characterized by two to five different archetypal shapes.Consequently,in some stands the majority of tree neighborhoods were best characterized by a different shape from that assigned at the stand level.Deviation from the stand average increased from the youngest stand in the mature development stage through the middle stands in the vertical diversification stage to the oldest stands in the horizontal diversification stage.The complexity of DDT shapes tended to increase along the chronosequence(from negative exponential and uniform toward concave and multi-modal),with shape richness highest mid-sequence and evenness peaking in the oldest stands.The high diversity of sub-stand structural complexity reduces the utility of standlevel diameter distributions as old-growth restoration targets.However,the presence in early-sequence stands of sub-stand diameter distributions common to later-sequence stands may facilitate active management at the neighborhood level to promote future old-growth condition.Restoration of substand diameter structures would likely require combining spatial perspectives,such as by augmenting tree-level croptree management with diameter distribution targets for the resulting tree neighborhoods. 展开更多
关键词 diameter distribution type Floating neighborhood Restoration silviculture Small-scale Structural complexity
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Alternative expressions for stand diameter in complex forests 被引量:1
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作者 Mark J.Ducey John A.Kershaw Jr. 《Forest Ecosystems》 SCIE CSCD 2023年第3期328-336,共9页
Quadratic mean diameter is the most frequently reported descriptor of the diameter distribution of forests.As such,it is often used as an indicator of forest stand structure,developmental stage,and ecological and econ... Quadratic mean diameter is the most frequently reported descriptor of the diameter distribution of forests.As such,it is often used as an indicator of forest stand structure,developmental stage,and ecological and economic potential.However,quadratic mean diameter can be heavily influenced by the presence or absence of large numbers of small stems in lower canopy strata,and it is also sensitive to left-truncation of the diameter distribution,making its interpretation across inventories with different protocols challenging.Here,we examine three alternative expressions of stand diameter:the arithmetic and quadratic mean diameter of the thickest 100 trees per hectare,and the basal area-weighted mean diameter.Using data from the United States Forest Inventory and Analysis program for New York and New England,these alternative expressions showed closer correlation with multiple stand structural variables than did quadratic mean diameter,including merchantable cubic and board foot volume per hectare,aboveground live tree carbon per hectare,and total number of live and dead standing trees greater than 40 cm diameter at breast height per hectare(previously proposed as an index of old-growth structure).Arithmetic and quadratic mean diameter of the thickest 100 trees per hectare showed nearly identical performance,and the strongest correlations across the board.We develop closed-form expressions for these variables when the diameter distribution is a Weibull,and illustrate their behavior relative to quadratic mean diameter for that situation.While the reasons for prevalence of quadratic mean diameter as an indicator remain valid,we suggest that these alternative measures should be more widely reported and analyzed to give a more informative depiction of stand structure and development in complex forests. 展开更多
关键词 Forest structure diameter at breast height Weibull distribution
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VAD治疗初诊多发性骨髓瘤患者的疗效及其影响因素 被引量:1
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作者 魏伟娜 吴玉君 吴倩 《实用癌症杂志》 2023年第1期52-55,共4页
目的探讨VAD治疗初诊多发性骨髓瘤(MM)患者的疗效及其影响因素。方法回顾性分析行VAD方案治疗的124例初诊MM患者临床资料,分析VAD治疗初诊MM患者的疗效及其影响因素。结果VAD治疗初诊MM患者治疗总有效率为65.32%(81/124),其中完全缓解(C... 目的探讨VAD治疗初诊多发性骨髓瘤(MM)患者的疗效及其影响因素。方法回顾性分析行VAD方案治疗的124例初诊MM患者临床资料,分析VAD治疗初诊MM患者的疗效及其影响因素。结果VAD治疗初诊MM患者治疗总有效率为65.32%(81/124),其中完全缓解(CR)20例(16.13%),部分缓解(PR)61例(49.19%),稳定(SD)27例(21.77%),疾病进展(PD)16例(12.90%)。按照治疗效果分为治疗有效组81例和治疗无效组43例,单因素分析显示:年龄、Durie-Salmon(DS)分期、C反应蛋白(CRP)、白蛋白、血肌酐、乳酸脱氢酶(LDH)、β_(2)微球蛋白(β_(2)-MG)与VAD治疗初诊MM疗效有关,差异有统计学意义(P<0.05);多因素分析显示:年龄≥60岁、DS分期Ⅲ期、CRP≥5 mg/L、白蛋白<35 g/L、血肌酐≥10.7 mmol/L、LDH≥240 U/L、β_(2)-MG≥3.5 mg/L是影响VAD治疗初诊MM疗效的高危因素(P<0.05)。结论VAD治疗初诊MM疗效较好,但疗效受年龄、DS分期、CRP、白蛋白、血肌酐、LDH、β_(2)-MG等因素影响,临床需加以重视。 展开更多
关键词 初诊多发性骨髓瘤 vad方案 临床疗效 影响因素 β_(2)微球蛋白
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Bedside ultrasonography of optic nerve sheath diameter for detection of raised intracranial pressure in nontraumatic neurocritically ill patients 被引量:1
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作者 Madhura Bhide Omender Singh +1 位作者 Deven Juneja Amit Goel 《World Journal of Critical Care Medicine》 2023年第1期10-17,共8页
BACKGROUND Delay in treatment of raised intracranial pressure(ICP)leads to poor clinical outcomes.Optic nerve sheath diameter(ONSD)by ultrasonography(US-ONSD)has shown good accuracy in traumatic brain injury and neuro... BACKGROUND Delay in treatment of raised intracranial pressure(ICP)leads to poor clinical outcomes.Optic nerve sheath diameter(ONSD)by ultrasonography(US-ONSD)has shown good accuracy in traumatic brain injury and neurosurgical patients to diagnose raised ICP.However,there is a dearth of data in neuro-medical intensive care unit(ICU)where the spectrum of disease is different.AIM To validate the diagnostic accuracy of ONSD in non-traumatic neuro-critically ill patients.METHODS We prospectively enrolled 114 patients who had clinically suspected raised ICP due to non-traumatic causes admitted in neuro-medical ICU.US-ONSD was performed according to ALARA principles.A cut-off more than 5.7 mm was taken as significantly raised.Raised ONSD was corelated with raised ICP on radiological imaging.Clinical history,general and systemic examination findings,SOFA and APACHE 2 score and patient outcomes were recorded.RESULTS There was significant association between raised ONSD and raised ICP on imaging(P<0.001).The sensitivity,specificity,positive and negative predictive value at this cut-off was 77.55%,89.06%,84.44% and 83.82% respectively.The positive and negative likelihood ratio was 7.09 and 0.25.The area under the receiver operating characteristic curves was 0.844.Using Youden’s index the best cut off value for ONSD was 5.75 mm.Raised ONSD was associated with lower age(P=0.007),poorer Glasgow Coma Scale(P=0.009)and greater need for surgical intervention(P=0.006)whereas no statistically significant association was found between raised ONSD and SOFA score,APACHE II score or ICU mortality.Our limitations were that it was a single centre study and we did not perform serial measurements or ONSD pre-and post-treatment or procedures for raised ICP.CONCLUSION ONSD can be used as a screening a test to detect raised ICP in a medical ICU and as a trigger to initiate further management of raised ICP.ONSD can be beneficial in ruling out a diagnosis in a low-prevalence population and rule in a diagnosis in a high-prevalence population. 展开更多
关键词 Intracranial pressure Intensive care unit Neuro-critical care Optic nerve sheath diameter ULTRASONOGRAPHY
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Measuring tree stem diameters and straightness with depth-image computer vision
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作者 Hoang Tran Keith Woeste +2 位作者 Bowen Li Akshat Verma Guofan Shao 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第5期1395-1405,共11页
Current techniques of forest inventory rely on manual measurements and are slow and labor intensive.Recent developments in computer vision and depth sensing can produce accurate measurement data at significantly reduc... Current techniques of forest inventory rely on manual measurements and are slow and labor intensive.Recent developments in computer vision and depth sensing can produce accurate measurement data at significantly reduced time and labor costs.We developed the ForSense system to measure the diameters of trees at various points along the stem as well as stem straightness.Time use,mean absolute error(MAE),and root mean squared error(RMSE)metrics were used to compare the system against manual methods,and to compare the system against itself(reproducibility).Depth-derived diameter measurements of the stems at the heights of 0.3,1.4,and 2.7 m achieved RMSE of 1.7,1.5,and 2.7 cm,respectively.The ForSense system produced straightness measurement data that was highly correlated with straightness ratings by trained foresters.The ForSense system was also consistent,achieving sub-centimeter diameter difference with subsequent measures and less than 4%difference in straightness value between runs.This method of forest inventory,which is based on depth-image computer vision,is time efficient compared to manual methods and less computationally and technologically intensive compared to Structure-from-Motion(SFM)photogrammetry and ground-based LiDAR or terrestrial laser scanning(TLS). 展开更多
关键词 Forest inventory Depth sensing Computer vision Tree diameter Stem straightness Trunk volume
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