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Cost-Effective Monitoring of the Fuel Air Equivalence-Ratio with a Lambda Sensor and a Microcontroller in a Downdraft Biomass Gasifier
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作者 Jean Fidele Nzihou Salou Hamidou +2 位作者 Ousmane Zoundi Frederic Ouattara Bila Gerard Segda 《Open Journal of Applied Sciences》 2024年第2期545-560,共16页
The operation of biomass treatment devices such as gasifiers is based on the control of key parameters that play an important role in product formation. These include: temperature, excess oxygen, relative humidity and... The operation of biomass treatment devices such as gasifiers is based on the control of key parameters that play an important role in product formation. These include: temperature, excess oxygen, relative humidity and biomass composition. This work focuses on excess oxygen and temperature. Unfortunately, flue gas oxygen analyzers are expensive and not accessible to small industries. However, the equivalence ratio is linked to excess oxygen and has the advantage of not depending on biomass composition. This study therefore focuses on the design and development of a device for controlling this equivalence ratio by measuring oxygen concentration using a self-propelled Lambda probe, and a system for monitoring this equivalence ratio using an Arduino Uno 3 microcontroller. The temperature is recorded with an accuracy of ±1.5°C. For a heating time of 10 minutes, the response time to temperature change is around 3 seconds, which is sufficient for the device to function properly. This simple device is an efficient and cost-effective means of checking the equivalence ratio. 展开更多
关键词 Equivalence ratio Biomass GASIFIcATION Lambda Sensor MIcROcONTROLLER c++
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等离子弧熔覆Fe-C-B-V系耐磨堆焊层的组织及性能研究 被引量:1
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作者 刘畅 饶嘉威 +3 位作者 蒋凤琦 沈毅锋 吴磊 浦娟 《热加工工艺》 北大核心 2024年第2期145-148,共4页
以硼铁、高碳铬铁、钒铁为原料,采用等离子弧熔覆技术在Q345钢表面堆焊Fe-C-B-V系铁基合金。使用金相显微镜、扫描电镜和X射线衍射仪等研究了堆焊层的显微组织;分别使用维氏硬度计和冲击试验机测量堆焊层的显微硬度和冲击韧性。结果表明... 以硼铁、高碳铬铁、钒铁为原料,采用等离子弧熔覆技术在Q345钢表面堆焊Fe-C-B-V系铁基合金。使用金相显微镜、扫描电镜和X射线衍射仪等研究了堆焊层的显微组织;分别使用维氏硬度计和冲击试验机测量堆焊层的显微硬度和冲击韧性。结果表明,堆焊层显微组织主要由马氏体、网格状Fe_(3)(C,B)和Fe_(2)B、弥散分布的碳化物及硼化物等(如VB_(2)、VC、Cr_(2)B)硬质相构成;堆焊层的平均硬度高达904.58 HV10、冲击功为68.5 J。堆焊过程中形成的硼化物、碳化物作为硬质相提高了堆焊层的硬度和耐磨性,形成的碳化钒使组织从鱼骨状变成网格状,细化了晶粒,提高了堆焊层的冲击韧性。 展开更多
关键词 等离子熔覆 Fe-c-B-v堆焊层 显微组织 显微硬度 冲击韧性
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纵向V型肋卷边C形不锈钢梁抗弯承载力试验研究
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作者 裴玉磊 叶彩凤 +2 位作者 陶忠 皇甫双娥 燕钊 《科技通报》 2024年第1期84-90,共7页
为研究在冷弯薄壁C形不锈钢梁腹板增设纵向加劲肋后对其极限抗弯承载力的影响,本文考虑腹板高度、高宽比以及加劲肋尺寸的不同,进行4组试件的对照试验研究。结果表明:对卷边C形不锈钢梁腹板进行加肋能良好地抑制腹板鼓曲,有效提高其极... 为研究在冷弯薄壁C形不锈钢梁腹板增设纵向加劲肋后对其极限抗弯承载力的影响,本文考虑腹板高度、高宽比以及加劲肋尺寸的不同,进行4组试件的对照试验研究。结果表明:对卷边C形不锈钢梁腹板进行加肋能良好地抑制腹板鼓曲,有效提高其极限抗弯承载力;加大加劲肋的尺寸会略微提高其极限抗弯承载力,但刚度略有降低;增加卷边C形不锈钢梁的腹板高度可有效提升其极限抗弯承载力和抵抗变形的能力。 展开更多
关键词 不锈钢 v型加劲肋 冷弯薄壁卷边c形钢梁 极限抗弯承载力
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单原子Al修饰空位缺陷V2C(MXene)对H_(2)气体表面吸附的第一性原理研究
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作者 龚安稳 胡梦晗 +4 位作者 曹宇 刘莹 曾勇谋 莫瀚宁 周晓龙 《原子与分子物理学报》 北大核心 2024年第3期9-16,共8页
基于第一性原理计算方法,对含空位缺陷的V2C(MXene)在不同位点修饰单原子Al的相关性能进行系统研究.研究表明,几何优化后得到含空位缺陷的V2C稳定结构表面能为-3075.53 J/m2,单原子Al修饰本征V2C单原子的吸附能为1.5511eV、单原子Al修... 基于第一性原理计算方法,对含空位缺陷的V2C(MXene)在不同位点修饰单原子Al的相关性能进行系统研究.研究表明,几何优化后得到含空位缺陷的V2C稳定结构表面能为-3075.53 J/m2,单原子Al修饰本征V2C单原子的吸附能为1.5511eV、单原子Al修饰空位缺陷V2C的吸附能为-2.0763 eV,这表明含空位缺陷的V2C,由于单原子Al的修饰可以明显改善晶体结构稳定性.进一步从态密度、分波态密度、吸氢能力研究发现,各体系态密度和分波态密度均出现分波越过费米能级的现象,表现出较强的金属性;V2C吸附H_(2)气体分子吸附能为-7.5867 eV,而空位缺陷V2C和单原子Al修饰空位缺陷V2C两个体系对H_(2)气体分子的吸附能仅为-0.9851 eV、-2.7130 eV,均未能进一步改善V2C对H_(2)气体分子的吸附性能,这对于储氢材料研发提供了一定的理论指导. 展开更多
关键词 MXene v2c 空位缺陷 单原子Al 吸附 第一性原理
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高度近视患者ICL V4c植入术后早期双眼视觉功能评估
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作者 唐凯莉 王静 +4 位作者 赵振波 韩冬 丁雨溪 张劲松 马立威 《国际眼科杂志》 CAS 2024年第4期634-640,共7页
目的:评估高度近视患者有晶状体眼后房型人工晶状体(ICL V4c)植入术后早期双眼视觉功能。方法:前瞻性研究。观察2019-05/2021-05在我院行双眼ICL植入术的高度近视患者35例70眼。术前和术后1 mo评估双眼全程视力、双眼对比度敏感度、双... 目的:评估高度近视患者有晶状体眼后房型人工晶状体(ICL V4c)植入术后早期双眼视觉功能。方法:前瞻性研究。观察2019-05/2021-05在我院行双眼ICL植入术的高度近视患者35例70眼。术前和术后1 mo评估双眼全程视力、双眼对比度敏感度、双眼立体视、双眼中间视觉及眩光敏感度、单眼波前像差及视觉质量调查问卷。结果:术后1 mo双眼裸眼远视力(UDVA)≤0.00(LogMAR)者35例(100%),双眼UDVA≥术前最佳矫正视力(CDVA)者16例(46%)。术后双眼裸眼远视力(UDVA)、中视力(UIVA,80 cm)较术前CDVA、最佳矫正远视力下中视力(DCIVA,80 cm)均有所提升(均P<0.05);双眼术后UIVA(60 cm)与术前DCIVA(60 cm)、双眼术后裸眼近视力(UNVA,40 cm)较术前最佳矫正远视力下近视力(40 cm),均无差异(均P>0.05)。术后双眼对比度敏感度较术前好转(P=0.001)。术后双眼中间视觉及眩光敏感度(无眩光)、中间视觉及眩光敏感度(眩光),较术前均无差异(均P>0.05)。手术前后双眼5 m和40 cm立体视比较均无差异(均P>0.05)。除在瞳孔直径3.0 mm下右眼全眼彗差术后较术前中位数减小,余全眼总高阶像差、三叶草像差、彗差及球面像差术后较术前中位数均有所增加。患者术前及术后的主观视觉质量量表评分总分均值由54.87分显著提升至80.92分(P<0.05),患者术后满意度高、无明确视觉干扰症状。结论:高度近视患者双眼植入ICL V4c术后早期单眼全眼高阶像差虽有所增加,但双眼视觉功能得到改善。 展开更多
关键词 高度近视 有晶状体眼后房型人工晶状体(IcL v4c) 双眼视觉功能
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自身炎症性疾病患者合并COVID-19严重程度的早期预测指标探讨
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作者 吕梦娜 李建斌 吴锐 《天津医药》 CAS 2024年第5期528-532,共5页
目的探讨血细胞比值及炎症指标对自身炎症性疾病(AIDs)合并新型冠状病毒肺炎(COVID-19)严重程度的预测价值。方法148例AIDs合并COVID-19患者根据COVID-19严重程度分为轻症组100例和重症组48例。比较2组患者感染后24~72 h内的红细胞沉降... 目的探讨血细胞比值及炎症指标对自身炎症性疾病(AIDs)合并新型冠状病毒肺炎(COVID-19)严重程度的预测价值。方法148例AIDs合并COVID-19患者根据COVID-19严重程度分为轻症组100例和重症组48例。比较2组患者感染后24~72 h内的红细胞沉降率(ESR)、C反应蛋白(CRP)、系统免疫炎症指数(SII)和白细胞-C反应蛋白比值(LeCR)等指标差异;采用Logistic回归分析AIDs合并COVID-19严重程度的危险因素;受试者工作特征(ROC)曲线评估各指标对AIDs合并COVID-19严重程度的预测价值。结果重症组ESR、CRP、血小板计数(PLT)、中性粒细胞-淋巴细胞比值(NLR)、血小板-淋巴细胞比值(PLR)、C反应蛋白-淋巴细胞比值(CLR)、C反应蛋白-白蛋白比值(CAR)、SII和血小板-白蛋白比值(PAR)高于轻症组,平均血小板体积(MPV)、淋巴细胞计数(LYM)、白蛋白(Alb)和LeCR低于轻症组(P<0.05)。Logistic回归分析显示,ESR升高是AIDs合并COVID-19严重程度的独立危险因素,LeCR和SII升高是保护因素。ROC曲线分析显示,LeCR对AIDs合并重症COVID-19的预测效能优于ESR和SII。结论ESR、SII和LeCR是预测AIDs并发COVID-19疾病严重程度的有效指标。 展开更多
关键词 自身炎症性疾病 新型冠状病毒肺炎 预后 白细胞-c反应蛋白比值
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Strong ground motion characteristics observed in the February 6,2023 M_(W)7.7 Türkiye earthquake
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作者 Faisal Mehraj Wani Jayaprakash Vemuri Chenna Rajaram 《Earthquake Science》 2024年第3期241-262,共22页
Türkiye is located in a seismically active region,where the Anatolian,African,and Arabian tectonic plates converge.High seismic hazards cause the region to be struck repeatedly by major earthquakes.On February 06... Türkiye is located in a seismically active region,where the Anatolian,African,and Arabian tectonic plates converge.High seismic hazards cause the region to be struck repeatedly by major earthquakes.On February 06,2023,a devastating M_(W)7.7 earthquake struck Türkiye at 01:17 am local time(01:17 UTC).In this regard,near and far-field ground motion data within the distance of 120 km are compiled and later characterized to identify the key ground motion intensity measures.Additionally,the vertical components of ground motions were examined to capture the complete three-dimensional nature of the seismic event.Moreover,the effect of Pulse-Like(PL)and Non-Pulse-Like(NPL)ground motion on a representative RC frame structure built as per the Türkiye code was investigated.The results indicate that PL behavior was observed in both horizontal and vertical components of ground motions and PL behavior were noted both near the epicenter and at higher distances from the epicenter.Moreover,the ratio of the peak vertical acceleration to peak horizontal acceleration at certain stations was found to be close to 1.Finally,the non-linear time history analysis of the representative reinforced concrete frame structure for ground motions recorded at stations located equidistant from the epicenter,indicated that PL ground motions led to more significant damage compared to NPL ground motions. 展开更多
关键词 Pulse-Like Non-Pulse-Like 2023 Türkiye earthquake v/H ratio reinforced concrete
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Activated Protein C Resistance in Patients with Pre-Eclampsia in Lagos, Nigeria
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作者 Nosimot O. Davies Titilope A. Adeyemo +2 位作者 Sunday I. Omisakin Akaninyene A. Udousoro Kabiru A. Rabiu 《Open Journal of Obstetrics and Gynecology》 2024年第4期575-590,共16页
Background: Preeclampsia is reported to complicate 2% - 8% of pregnancies globally and is an important cause of maternal and perinatal morbidity and mortality. The aetiology and pathogenesis are still poorly understoo... Background: Preeclampsia is reported to complicate 2% - 8% of pregnancies globally and is an important cause of maternal and perinatal morbidity and mortality. The aetiology and pathogenesis are still poorly understood and substantial improvement has not been made in the prediction, prevention and treatment of the disease. Objective: To compare the frequency of activated protein C resistance (APC-R) in patients with pre-eclampsia to that of normotensive pregnant women and to determine the correlation between activated protein ratio (APC-ratio) and the severity of pre-eclampsia. Methodology: A cross-sectional study was carried out in 100 pre-eclamptic patients and 100 normotensive pregnant controls. The APC-ratio was determined using the modified activated partial thromboplastin time. Study participants with APC-ratio of less than 2.0 were defined as having APC-R. Data was analyzed using SPSS version 22.0. Results: Mean APC-ratio was significantly lower in pre-eclamptics (2.89 ± 1.70) compared to normotensive pregnant women (3.57 ± 1.06) (p = 0.0008) and the levels were also higher in mild (2.95 ± 1.15) compared to severe pre-eclamptics (2.62 ± 1.14). The frequency of APC-R was 26% among women with pre-eclampsia compared to 4% among normotensive controls (p = 0.000). Among 100 pre-eclamptic women 7 (21.2%) out of 33 with mild pre–eclampsia had APC-R, while 19 (28.4%) out of 67 with severe pre-eclampsia had APC-R. APC-ratio had a significant negative correlation with mean arterial blood pressure (r = −0.324;p = 0.000) and proteinuria (r = −0.379;p = 0.000) among study participants. Conclusion: The frequency of activated protein c resistance is significantly higher in pre-eclamptics compared to normotensive pregnant women and this is more pronounced in those with severe pre-eclampsia compared with those with mild disease. APC-R may therefore be used as a marker of severity in the disease. 展开更多
关键词 Activated Protein c Resistance Activated Protein c ratio PRE-EcLAMPSIA
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ICLV4c植入术后远期疗效的研究进展
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作者 王妙妙 王慧娴 +1 位作者 张旭 李文静 《国际眼科杂志》 2024年第2期260-263,共4页
随着科技的快速发展与电子产品的广泛应用,高度近视患者的数量逐渐增加。同时,由于手术技术的持续优化和后房型人工晶状体材料以及制造工艺的不断进步,ICL V4c植入术已逐渐成为治疗高度近视的主要手术方式之一。在步入社会信息化的高速... 随着科技的快速发展与电子产品的广泛应用,高度近视患者的数量逐渐增加。同时,由于手术技术的持续优化和后房型人工晶状体材料以及制造工艺的不断进步,ICL V4c植入术已逐渐成为治疗高度近视的主要手术方式之一。在步入社会信息化的高速时代,人们对ICL V4c植入术后的远期疗效更加关注。不仅希望视力清晰,更追求视觉的舒适度与持久性。因此,本文将特别针对近3 a内至少有2 a跟踪观察的ICL V4c植入术后疗效的研究进展进行详细探讨,旨在从ICL V4c植入术后的视觉质量,手术的安全性、有效性、稳定性,以及可能出现的手术并发症这三个维度对ICL V4c植入术后远期疗效的最新研究进展进行综述。 展开更多
关键词 IcL v4c植入术 高度近视 远期疗效
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Refractive outcomes after V4c Toric collamer lens implantation over 1y of follow-up
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作者 Humberto Carreras-Díaz Josefina Reñones de Abajo +1 位作者 María del Rosario Carreras-Díaz Amalia Lorente-Velázquez 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第7期1322-1330,共9页
AIM:To evaluate refractive outcomes and corneal astigmatism changes after Toric implantable collamer lens with a central port(V4c T-ICL)implantation over 1y of follow-up.METHODS:A retrospective study was performed inc... AIM:To evaluate refractive outcomes and corneal astigmatism changes after Toric implantable collamer lens with a central port(V4c T-ICL)implantation over 1y of follow-up.METHODS:A retrospective study was performed including 50 eyes of 50 patients that underwent V4c T-ICL implantation.Uncorrected(UDVA)and corrected(CDVA)distance visual acuities,refraction,refractive and corneal astigmatism changes and corneal coupling correction were evaluated preoperatively,1 and 12mo postoperatively.Vector analysis was used for astigmatism changes.Coefficient of adjustment(CAdj)was calculated for corneal coupling analysis.RESULTS:The mean UDVA achieved was 0.03 logMAR at 1mo and remained unchanged throughout the whole follow-up(P=0.193).At the last visit,84%of the eyes achieved a CDVA of 0.00 logMAR or better.Regarding spherical equivalent refraction(SEQ),96%of eyes were ranges of±1.00 D and 84%of them within±0.50 D.Also,94%of eyes had a remaining refractive cylinder within±1.00 D and 78%of them within±0.50 D.Both,SEQ and refractive cylinder,remain stable over the postoperative follow-up(P=1.000 and P=0.660,respectively).In terms of surgically induced astigmatism(SIA),no statistically significant differences were found over the follow-up(P=0.102)and under correction was found with a correction index lower than the unit at each visit.A keratometric astigmatism induced of 0.59±0.53(vector mean:0.26×73º)D was reached at the last visit.No significant changes in terms of corneal astigmatism orientation were reported over post-surgery visits(P=0.129 and P=0.097 at 1 and 12mo respectively).No clinical significance was found for CAdj on with-the-rule astigmatism.No postoperative complications resulting from the surgery were found.CONCLUSION:Refractive outcomes suggest that the V4c T-ICL implantation for correction of myopic astigmatism was satisfactory in terms of effectiveness,safety,and stability during 1y of follow-up.Corneal astigmatism induced by the incision around 0.5 D is achieved according to the remaining refractive cylinder found at one-year post-surgery.Corneal coupling analysis results in no unexpected spherical change. 展开更多
关键词 v4c Toric collamer lens corneal astigmatism surgically induced astigmatism corneal coupling
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Serum cystatin C,monocyte/high-density lipoprotein-C ratio,and uric acid for the diagnosis of coronary heart disease and heart failure
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作者 Ming Li Da-Hao Yuan +2 位作者 Zhi Yang Teng-Xiang Luw Xiao-Biao Zou 《World Journal of Clinical Cases》 SCIE 2024年第18期3461-3467,共7页
BACKGROUND Coronary heart disease(CHD)and heart failure(HF)are the major causes of morbidity and mortality worldwide.Early and accurate diagnoses of CHD and HF are essential for optimal management and prognosis.Howeve... BACKGROUND Coronary heart disease(CHD)and heart failure(HF)are the major causes of morbidity and mortality worldwide.Early and accurate diagnoses of CHD and HF are essential for optimal management and prognosis.However,conventional diagnostic methods such as electrocardiography,echocardiography,and cardiac biomarkers have certain limitations,such as low sensitivity,specificity,availability,and cost-effectiveness.Therefore,there is a need for simple,noninvasive,and reliable biomarkers to diagnose CHD and HF.AIM To investigate serum cystatin C(Cys-C),monocyte/high-density lipoprotein cholesterol ratio(MHR),and uric acid(UA)diagnostic values for CHD and HF.METHODS We enrolled 80 patients with suspected CHD or HF who were admitted to our hospital between July 2022 and July 2023.The patients were divided into CHD(n=20),HF(n=20),CHD+HF(n=20),and control groups(n=20).The serum levels of Cys-C,MHR,and UA were measured using immunonephelometry and an enzymatic method,respectively,and the diagnostic values for CHD and HF were evaluated using receiver operating characteristic(ROC)curve analysis.RESULTS Serum levels of Cys-C,MHR,and UA were significantly higher in the CHD,HF,and CHD+HF groups than those in the control group.The serum levels of Cys-C,MHR,and UA were significantly higher in the CHD+HF group than those in the CHD or HF group.The ROC curve analysis showed that serum Cys-C,MHR,and UA had good diagnostic performance for CHD and HF,with areas under the curve ranging from 0.78 to 0.93.The optimal cutoff values of serum Cys-C,MHR,and UA for diagnosing CHD,HF,and CHD+HF were 1.2 mg/L,0.9×10^(9),and 389μmol/L;1.4 mg/L,1.0×10^(9),and 449μmol/L;and 1.6 mg/L,1.1×10^(9),and 508μmol/L,respectively.CONCLUSION Serum Cys-C,MHR,and UA are useful biomarkers for diagnosing CHD and HF,and CHD+HF.These can provide information for decision-making and risk stratification in patients with CHD and HF. 展开更多
关键词 Serum cystatin c Monocyte/high-density lipoprotein-c ratio Uric acid coronary heart disease Heart failure Risk stratification
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Frequency of the C677T Polymorphism of MTHFR, G20210A of Prothrombin and R506Q of Factor V Leiden in Type 2 Diabetics in Abidjan
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作者 N’Guessan-Blao Rebecca Yapo Vincent +3 位作者 Yayo-Ayé Mireille Adjambri Eusèbe Koné-Koné Fatoumata Sawadogo Duni 《Open Journal of Genetics》 CAS 2024年第1期13-25,共13页
In Africa, the prevalence of diabetes is escalating and remains a concern due to the numerous complications it causes. Vascular damage associated with diabetes leads to a prothrombotic state observed in diabetic indiv... In Africa, the prevalence of diabetes is escalating and remains a concern due to the numerous complications it causes. Vascular damage associated with diabetes leads to a prothrombotic state observed in diabetic individuals. Diabetes is a complex and multifactorial disease involving genetic components. With the aim of preventing complications and contributing to an efficient management of diabetes, we investigated genes likely to lead to a risk of thrombosis, in particular the C677T of MTHFR, G20210A of prothrombin, and R506Q of factor V Leiden in type 2 diabetics in Abidjan receiving ambulatory care. A descriptive cross-sectional study was carried out on consenting type 2 diabetic patients. Mutation detection was carried out using the PCR-RFLP method employing restriction enzymes. Hemostasis tests (fibrinogen, D-dimers, fibrin monomers, and von Willebrand factor) were performed using citrate tubes on the Stage? Star Max automated system. Plasminogen activator inhibitor was assayed by ELISA method, and biochemical parameters were determined using the COBAS C311. The study population consisted of 45 diabetic patients, 51.1% of whom presented vascular complications, mainly neuropathy. Disturbances in hemostasis parameters were observed, with 15.5% of patients showing an increase in fibrin monomers. Mutation analysis revealed an absence of factor V mutation (factor V Leiden) and of G20210A mutation of the prothrombin gene. However, 15.6% of subjects had a heterozygous C677T mutation of MTHFR, with 57% of them being anemic. The exploration of biological and genetic factors associated with thrombotic risk is of significant interest in the optimal management of African type 2 diabetics. 展开更多
关键词 Type 2 Diabetes c677T of MTHFR G20210A Factor v Leiden Thrombosis
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高度近视患者植入ICL V4c后眼前节参数的早期结果
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作者 潘冰心 吴杰 +2 位作者 蒋鹏飞 徐珊 何坤 《国际眼科杂志》 CAS 2024年第3期491-494,共4页
目的:研究高度近视患者植入带中心孔的植入式collamer晶状体(ICL V4c)后眼前节参数的早期结果。方法:纳入2019-02/2022-09在我院行ICL V4c植入术且随访1 a的高度近视患者82例160眼,其中男42例82眼,女40例78眼,年龄26.0±4.6(21-37)... 目的:研究高度近视患者植入带中心孔的植入式collamer晶状体(ICL V4c)后眼前节参数的早期结果。方法:纳入2019-02/2022-09在我院行ICL V4c植入术且随访1 a的高度近视患者82例160眼,其中男42例82眼,女40例78眼,年龄26.0±4.6(21-37)岁。术前检测患者的眼前节一般特征:球镜度数、平均角膜水平曲率、水平角膜直径(WTW)和轴向长度(AL);术前,术后1 d,1 wk,1、3、6 mo测量患者的眼内压(IOP)、内皮细胞密度(ECD)、中央前房深度(CACD)、前房容积(ACV)、前房角(ACA);术后1 d,1 wk,1、6 mo,1 a测量患者ICL V4c光学区后表面中心到晶状体前表面的距离(拱高)。结果:患者术前平均球镜度数为-7.56±2.55 D,平均角膜水平曲率为42.89±1.47 D,WTW为11.64±0.37 mm,AL为26.64±0.93 mm。眼压基线为15.97±2.13 mmHg,ICL V4c植入后各时间点眼压与术前相比无差异(F=0.875,P=0.504);ECD基线为2989.30±140.78 cell/mm^(2),ICL V4c植入后6 mo的ECD与术前相比无差异(t=1.475,P=0.142);CACD基线为3.19±0.21 mm,ACV基线为210.30±27.7 mm 3,术后各时间点CACD、ACV均显著低于术前(F=111.10、288.38,均P<0.001);ACA基线为35.44°±11.27°,ICL V4c植入后各时间点ACA显著低于术前(F=21.23,P<0.001)。术后1 d拱高为665.32±184.03μm,术后1 wk,1、6 mo,1 a与术后1 d相比,拱高继续显著减少(F=52.10,P<0.001),但在术后6 mo,1 a时保持稳定,与1 mo时相比均无差异(P>0.05)。结论:ICL V4c在术后1 a的随访中具有一定安全性和有效性,植入后早期眼前节参数趋于稳定。 展开更多
关键词 高度近视 眼前节 拱高 人工晶状体 带中心孔的植入式collamer晶状体(IcL v4c)
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外周血NLR、PLR、MPVLR联合CRP在儿童难治性肺炎支原体肺炎中的预测价值
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作者 王娟 申翠平 《检验医学与临床》 CAS 2024年第11期1631-1635,共5页
目的探讨肺炎支原体肺炎(MPP)患儿外周血中性粒细胞计数(NEU)/淋巴细胞计数(LYM)比值(NLR)、血小板计数(PLT)/LYM比值(PLR)、平均血小板体积(MPV)/LYM比值(MPVLR)联合C反应蛋白(CRP)在儿童难治性肺炎支原体肺炎(RMPP)中的预测价值。方... 目的探讨肺炎支原体肺炎(MPP)患儿外周血中性粒细胞计数(NEU)/淋巴细胞计数(LYM)比值(NLR)、血小板计数(PLT)/LYM比值(PLR)、平均血小板体积(MPV)/LYM比值(MPVLR)联合C反应蛋白(CRP)在儿童难治性肺炎支原体肺炎(RMPP)中的预测价值。方法选取2021年6月至2022年6月在山西省长治市人民医院儿科住院的427例MPP患儿作为研究对象,将常规MPP患儿分为GMPP组(341例),RMPP患儿分为RMPP组(86例)。比较两组住院时间、白细胞计数、NEU、LYM、PLT、MPV、NLR、PLR、MPVLR及乳酸脱氢酶(LDH)、红细胞沉降率、CRP、谷丙转氨酶(ALT)、血红蛋白水平。采用多因素Logistic回归分析MPP患儿进展为RMPP的危险因素。绘制受试者工作特征(ROC)曲线分析NLR、PLR、MPVLR、CRP在MPP患儿进展为RMPP中的预测价值。结果两组NEU、LYM、NLR、PLT、PLR、MPVLR、CRP、LDH、ALT水平、住院时间比较,差异均有统计学意义(P<0.05)。NLR、PLR、MPVLR、CRP水平升高是MPP患儿进展为RMPP的危险因素(P<0.05)。ROC曲线分析结果显示,NLR、PLR、MPVLR、CRP单独预测MMP患儿进展为RMPP的曲线下面积(AUC)分别为0.663、0.601、0.646、0.724。NLR联合CRP、PLR联合CRP、MPVLR联合CRP预测MMP患儿进展为RMPP的AUC分别为0.740、0.729、0.723。结论外周血NLR、PLR、MPVLR分别联合CRP在MPP患儿进展为RMPP中的预测价值比单项指标预测更高。 展开更多
关键词 肺炎支原体肺炎 难治性肺炎支原体肺炎 中性粒细胞计数/淋巴细胞计数比值 血小板计数/淋巴细胞计数比值 平均血小板体积/淋巴细胞计数比值 c反应蛋白
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Maize straw application as an interlayer improves organic carbon and total nitrogen concentrations in the soil profile: A four-year experiment in a saline soil
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作者 CHANG Fang-di WANG Xi-quan +7 位作者 SONG Jia-shen ZHANG Hong-yuan YU Ru WANG Jing LIU Jian WANG Shang JI Hong-jie LI Yu-yi 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第6期1870-1882,共13页
Soil salinization is a critical environmental issue restricting agricultural production.Deep return of straw to the soil as an interlayer (at 40 cm depth) has been a popular practice to alleviate salt stress.However,t... Soil salinization is a critical environmental issue restricting agricultural production.Deep return of straw to the soil as an interlayer (at 40 cm depth) has been a popular practice to alleviate salt stress.However,the legacy effects of straw added as an interlayer at different rates on soil organic carbon (SOC) and total nitrogen (TN) in saline soils still remain inconclusive.Therefore,a four-year (2015–2018) field experiment was conducted with four levels (i.e.,0,6,12and 18 Mg ha~(–1)) of straw returned as an interlayer.Compared with no straw interlayer (CK),straw addition increased SOC concentration by 14–32 and 11–57%in the 20–40 and 40–60 cm soil layers,respectively.The increases in soil TN concentration (8–22 and 6–34%in the 20–40 and 40–60 cm soil layers,respectively) were lower than that for SOC concentration,which led to increased soil C:N ratio in the 20–60 cm soil depth.Increases in SOC and TN concentrations in the 20–60 cm soil layer with straw addition led to a decrease in stratification ratios (0–20 cm:20–60 cm),which promoted uniform distributions of SOC and TN in the soil profile.Increases in SOC and TN concentrations were associated with soil salinity and moisture regulation and improved sunflower yield.Generally,compared with other treatments,the application of 12 Mg ha~(–1) straw had higher SOC,TN and C:N ratio,and lower soil stratification ratio in the2015–2017 period.The results highlighted that legacy effects of straw application as an interlayer were maintained for at least four years,and demonstrated that deep soil straw application had a great potential for improving subsoil fertility in salt-affected soils. 展开更多
关键词 straw addition INTERLAYER soil organic carbon soil nitrogen c:N ratio saline soil
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老年髋关节置换术患者围术期血清VitD、CK、CRP/ALB水平变化及其对预后的预测价值 被引量:1
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作者 李涧 沈沐 +3 位作者 杨渊 金佳 姜习凤 郁嘉娴 《国际检验医学杂志》 CAS 2023年第8期951-955,共5页
目的探究老年髋关节置换术患者围术期血清维生素D(VitD)、肌酸激酶(CK)、C反应蛋白与清蛋白比值(CRP/ALB)水平变化及对预后的影响。方法选取2020年11月至2021年11月于苏州大学附属第二医院行髋关节置换术治疗的110例老年股骨颈骨折患者... 目的探究老年髋关节置换术患者围术期血清维生素D(VitD)、肌酸激酶(CK)、C反应蛋白与清蛋白比值(CRP/ALB)水平变化及对预后的影响。方法选取2020年11月至2021年11月于苏州大学附属第二医院行髋关节置换术治疗的110例老年股骨颈骨折患者,术后6个月通过Harris髋关节功能评分(HHS)评估预后情况,比较预后良好组(HHS分值≥80分)、预后不良组(HHS分值<80分)术前一般资料、疼痛程度[疼痛视觉模拟评分法(VSA评分)]、病情程度[急性生理功能和慢性健康状况评分系统Ⅱ(APACHEⅡ评分)]和围术期血清VitD、CK、CRP/ALB水平,分析术前血清VitD、CK、CRP/ALB与疼痛程度、病情程度的相关性,并分析术后血清VitD、CK、CRP/ALB预测老年股骨颈骨折患者髋关节置换术预后的价值。结果预后良好组术后6个月HHS分值高于预后不良组(t=12.175,P<0.05);预后不良组骨质疏松症发生率、术前APACHEⅡ评分高于预后良好组(P<0.05);预后不良组术前、术后3 d血清VitD水平均低于预后良好组,CK、CRP/ALB均高于预后良好组(P<0.05);术前血清VitD水平与APACHEⅡ评分呈负相关,血清CK、CRP/ALB与APACHEⅡ评分呈正相关(P<0.05);术后3 d血清VitD、CK、CRP/ALB预测老年股骨颈骨折患者髋关节置换术后6个月预后不良的曲线下面积(AUC)均>0.700,联合预测的AUC最大,为0.938。结论老年髋关节置换术患者围术期血清VitD、CK、CRP/ALB与病情程度及预后密切相关,术后早期检测各指标水平在预测预后方面具有一定价值。 展开更多
关键词 髋关节置换术 维生素D 肌酸激酶 c反应蛋白与清蛋白比值 预后
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淋巴细胞与单核细胞比值、C反应蛋白与前白蛋白比值检测对甲型流感病毒重症感染婴幼儿的临床价值
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作者 于瑞杰 卢洋 陈杰 《中国妇幼健康研究》 2024年第4期74-78,共5页
目的 探讨淋巴细胞与单核细胞比值(LMR)、C反应蛋白与前白蛋白比值(CRP/PA)预测甲型流感病毒重症感染婴幼儿的临床价值。方法 选取2019年1月至2022年12月泰安市妇幼保健院儿内科住院的婴幼儿甲型流感病毒感染重症组(192例)、轻症组(187... 目的 探讨淋巴细胞与单核细胞比值(LMR)、C反应蛋白与前白蛋白比值(CRP/PA)预测甲型流感病毒重症感染婴幼儿的临床价值。方法 选取2019年1月至2022年12月泰安市妇幼保健院儿内科住院的婴幼儿甲型流感病毒感染重症组(192例)、轻症组(187例)及健康对照者(393例),检测其血常规、CRP及PA水平,计算中性粒细胞/淋巴细胞比值(NLR)、LMR、血小板/淋巴细胞比值(PLR)、系统免疫炎症指数(SII)、CRP/PA。采用受试者工作特征(ROC)曲线和Logistic回归分析LMR、CRP/PA对甲型流感病毒重症感染的诊断及预测价值。结果 与对照组和轻症组比较,重症组NLM、PLR、SII、CRP/PA均显著升高,LMR显著降低(分别为1.09、88.07、310.75、0.05和3.90,P<0.05)。与对照组相比,轻症组CRP/PA显著升高,LMR显著降低(分别为0.04和6.31,P<0.05)。ROC曲线显示,诊断重症感染时,CRP/PA的特异度最高,为96.1%,LMR、CRP/PA联合检测的灵敏度、ROC曲线下面积(AUC)均优于单项检测(分别为88.5%、0.941)。LMR、CRP/PA联合检测对轻症与重症感染鉴别诊断的灵敏度、特异度和AUC均优于单项检测(分别为76.4%、60.2%、0.707)。校正年龄、性别及NLM、PLR、SII后,CRP/PA的升高与LMR的降低与甲型流感病毒感染独立相关,并区分轻症和重症。结论 甲型流感病毒感染患儿CRP/PA升高与LMR降低,还有助于区分轻症和重症,可为预测感染严重程度的指标,LMR、CRP/PA联合分析对轻重症感染的鉴别诊断具有重要价值。 展开更多
关键词 淋巴细胞与单核细胞比值 c反应蛋白与前白蛋白比值 甲型流感病毒 重症感染 婴幼儿
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C反应蛋白/白蛋白比值和系统免疫炎症指数与浆液性卵巢癌患者临床病理特征和预后的关系
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作者 周玉飞 李云辉 +1 位作者 李冰熠 侯青霞 《检验医学》 CAS 2024年第4期363-368,共6页
目的 探讨术前C反应蛋白(CRP)/白蛋白(Alb)比值(CAR)和系统免疫炎症指数(SII)与浆液性卵巢癌患者临床病理特征和预后的关系。方法 选取2017年1月—2021年1月洛阳市中心医院浆液性卵巢癌患者132例。收集患者一般临床资料和术前血小板(PLT... 目的 探讨术前C反应蛋白(CRP)/白蛋白(Alb)比值(CAR)和系统免疫炎症指数(SII)与浆液性卵巢癌患者临床病理特征和预后的关系。方法 选取2017年1月—2021年1月洛阳市中心医院浆液性卵巢癌患者132例。收集患者一般临床资料和术前血小板(PLT)计数、中性粒细胞(NEUT)计数、淋巴细胞(LY)计数、CRP、Alb检测结果,并计算CAR和SII。根据CAR和SII的中位数,将患者分别分为低CAR组、高CAR组和低SII组、高SII组,分析不同CAR、SII组间临床病理特征、无复发生存期(RFS)和总生存期(OS)的差异。采用单因素和多因素Cox回归分析评估浆液性卵巢癌患者RFS和OS的影响因素。结果 高CAR组和高SII组国际妇产科联盟(FIGO)分期、组织学分级、淋巴转移分别与低CAR组和低SII组比较,差异均有统计学意义(P<0.05)。高CAR组和高SII组术后残留肿瘤直径<1 cm所占比例均分别低于低CAR组和低SII组(P<0.05)。高CAR组和高SII组的RFS和OS均分别显著低于低CAR组和低SII组(P<0.05)。FIGO分期(Ⅲ期+Ⅳ期)、高CAR和高SII是影响浆液性卵巢癌患者术后RFS的独立危险因素[风险比(HR)分别为2.258、2.665、4.432,95%可信区间(CI)分别为1.125~4.534、1.401~5.069、2.227~8.821]。FIGO分期(Ⅲ期+Ⅳ期)、糖链抗原125(CA125)(≥35 U/L)、高CAR和高SII是浆液性卵巢癌患者术后OS的独立危险因素(HR分别为4.574、4.417、3.167、5.500,95%CI分别为1.660~12.607、1.426~13.686、1.392~7.206、2.254~13.424)。结论 浆液性卵巢癌患者CAR和SII与FIGO分期、组织学分级和淋巴转移等临床病理特征有关,且术前高CAR和高SII是患者预后不良的独立危险因素,可作为浆液性卵巢癌患者预后评估的参考指标。 展开更多
关键词 c反应蛋白/白蛋白比值 系统免疫炎症指数 浆液性卵巢癌 预后
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细菌性肺炎患者血清LTB4、NLCR及CRP/PA变化及其与肺损伤程度的关系
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作者 张春红 程波 曹建 《中南医学科学杂志》 CAS 2024年第4期596-598,672,共4页
目的探讨细菌性肺炎患者血清白三烯B4(LTB4)、中性粒细胞/淋巴细胞计数比值(NLCR)及C-反应蛋白与前白蛋白(CRP/PA)比值变化及其与肺损伤程度的关系。方法回顾性选取172例细菌性肺炎患者(观察组)和同期140例健康体检者(对照组)的临床资料... 目的探讨细菌性肺炎患者血清白三烯B4(LTB4)、中性粒细胞/淋巴细胞计数比值(NLCR)及C-反应蛋白与前白蛋白(CRP/PA)比值变化及其与肺损伤程度的关系。方法回顾性选取172例细菌性肺炎患者(观察组)和同期140例健康体检者(对照组)的临床资料,根据肺损伤程度,将患者分为轻中度组和重度组。比较各组LTB4、NLCR及CRP/PA水平,分析LTB4、NLCR及CRP/PA联合评估患者肺损伤程度的价值。结果与对照组比较,观察组LTB4、NLCR及CRP/PA水平更高(P<0.05);与轻中度组比较,重度组LTB4、NLCR及CRP/PA水平更高(P<0.05);ROC结果显示,LTB4、NLCR和CRP/PA评估患者肺损伤程度的AUC为0.793、0.717、0.758,三者联合评估患者肺损伤程度的AUC为0.933,高于单项评估(P<0.05)。结论LTB4、NLCR及CRP/PA在细菌性肺炎患者中表达水平均会升高,且其均与肺损伤程度有关,其联合评估肺损伤程度的价值较高。 展开更多
关键词 细菌性肺炎 白三烯B4 中性粒细胞/淋巴细胞计数比值 c-反应蛋白/前白蛋白 肺损伤程度
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基于跨层信息的C-V2X缓存分配算法
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作者 陈秉试 《长江信息通信》 2023年第1期29-32,共4页
针对城市场景的蜂窝车联网(cellular vehicle to everything,C-V2X)中车辆缓存节点高效选择和合理的缓存文件分配问题,提出了基于跨层信息的C-V2X缓存分配算法(Cross-layer Caching Allocation for C-V2X,CLCA)。该算法在LTE-V2X mode3... 针对城市场景的蜂窝车联网(cellular vehicle to everything,C-V2X)中车辆缓存节点高效选择和合理的缓存文件分配问题,提出了基于跨层信息的C-V2X缓存分配算法(Cross-layer Caching Allocation for C-V2X,CLCA)。该算法在LTE-V2X mode3模式下,由基站周期地收集覆盖范围内节点的连接度、信噪比和信道接入时延信息,并重新划分邻居归属,构建跨层信息邻接矩阵,再采用贪婪分配的方法筛选缓存节点,以减少缓存节点数量,节约通信资源并降低开销。进而,以服从Zipf分布的文件流行度分布为基础,采用文件流行度预测概率与历史周期实际流行度概率加权叠加的方式,提高文件流行度预测的准确性,再根据缓存容量合理配置缓存文件。仿真分析表明,该算法可以有效提高节点的文件获取效率,降低文件传输时延,减少基站负载。 展开更多
关键词 跨层信息 蜂窝车联网 缓存分配 信道接入时延 信噪比
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