A prediction model for large vessel occlusion in suspected stroke patients based on available prehospital information

Objective:Early and accurate identification of large vessel occlusion(LVO)acute ischemic stroke(AIS)patients is critically important for stroke management.Practicable scales with simple items can facilitate prehospital paramedics distinguishing LVO-AIS patients with high efficiency and help to avoid unnecessary and costly delays.The current study aims to develop a screening tool to predict AIS-LVO patients based on prehospital available data.Method:A total of 251 suspected stroke patients who were transported to the emergency department of our hospital via emergency medical services were consecutively enrolled from August,2020 to January,2022.Data including demographic information,medical history,clinical manifestations,and vital signs were collected.A multivariate logistic regression model was developed based on statistically significant variables selected from univariate analysis.Result:Forty-two patients(16.7%)were diagnosed as LVO-AIS based on imaging validation at admission.A comprehensive model was developed with past medical history factors such as atrial fibrillation and coronary heart disease,vital signs such as systolic blood pressure,and prominent symptoms and signs such as gaze palsy,facial paralysis,and dysarthria.The model showed better diagnostic performance in terms of area under the receiver operating characteristic curves(0.884,95%CI,0.830-0.939),which was higher than other common prehospital prediction scales such as the Face,Arm,Speech,Time test(FAST),the Field Assessment Stroke Triage for Emergency Destination(FAST-ED)scale,and the Gaze-Face-Arm-Speech-Time test(G-FAST).Calibration curve analysis,decision curve analysis,and clinical impact curve analysis further validated the reliability,net benefit,and potential clinical impact of the prediction model,respectively.Conclusion:We conducted a prediction model based on prehospital accessible factors including past history of atrial fibrillation and coronary heart disease,systolic blood pressure,and signs such as gaze palsy,facial palsy,and dysarthria.The prediction model showed good diagnostic power and accuracy for identification of the high-risk patients with LVO and may become an effective tool for the LVO recognition in prehospital settings.Future studies are warranted to refine and validate the model further in order to enhance the accuracy and objectivity of clinical judgments.

Mechanical thrombectomy and postoperative complications after acute ischemic stroke with large vessel occlusion

Acute ischemic stroke is one of the common discases in Chinese,among which acute ischemic stroke with large vessel occlusion(AIS-LVO)has thc most serious complications and has the risk of death.Studies have shown that reperfusion is a first-line treatment for the effective rescue of ischemic brain tissue,usually mainly by mechanical|hrombectomy(MT),supplemented by intravenous thrombolysis.However,there are still complications after large blood vessel occlusion and MT.such as blecding and infection at the puncture point,vasospasm,vascular dissection,subarachnoid hemorrhage,hcmonhagic transfomation,reembolization,and massive cerebral infarction,ctc.The high risk factors and corresponding measures of complications after MT by revicwing the rescarch analysis.

Drug-coated balloons for treating de novo lesions in large coronary vessels:A case report

BACKGROUND Percutaneous transluminal coronary angioplasty,while an effective intervention,can frequently lead to acute occlusion with severe consequences.Although clinical trials have demonstrated the efficacy of drug-coated balloons(DCB)in treating acute coronary artery occlusion and in preventing restenosis,there has been limited exploration on the use of DCB in treating de novo lesions in large vessels.Currently,DCB are only recommended for patients with small vessel lesions and in-stent restenosis lesions,those at high risk of bleeding,and other special groups of patients.CASE SUMMARY This report presents a case of successful drug-coated balloon treatment of de novo lesions in large coronary vessels.Postoperatively,the patient demonstrated favorable recovery,with subsequent examination results revealing no significant differences from the previous examination.CONCLUSION The successful treatment of the patient in our case highlights the potential of DCB in the treatment of de novo lesions in large coronary vessels.

Ice Resistance Assessment for a Large Size Vessel Running in a Narrow Ice Channel Behind an Icebreaker

Large size vessels sailing in continuous level ice and broken ice of high concentration are mostly assisted by icebreakers.This is done in order to provide for fast transportation through the North Sea Route and safe operation in extreme ice conditions.Currently,new large size gas and oil carriers and container ships are being designed and built with beams much greater than the beams of existing icebreakers.At the same time,no mathematical description exists for the breaking mechanism of ice channel edges,when such vessels move under icebreaker escort.This paper suggests a simple method for assessment of the ice resistance in the case of a large ship running in an icebreaker channel;the method is based on modification of well-known semi-empirical methods for calculation of the ice resistance to ships in level and broken ice.The main feature of the proposed calculation scheme consists in that different methods are applied to estimate the ice resistance in broken ice and due to breaking of level ice edges.The combination of these methods gives a deliverable ice resistance of a large size vessel moving under icebreaker assistance in a newly made ice channel.In general,proposed method allows to define the speed of a carrier moving in an ice channel behind a modern linear icebreaker and could be applied at the ship design stage and during development of the marine transportation system.The paper also discusses the ways for further refinement of the assessment procedure suggested.

Nine-year clinical outcomes of drug-eluting stents vs. bare metal stents for large coronary vessel lesions

Objectives To evaluate the very long-term safety and effectiveness of drug-eluting stents （DES） compared to bare-metal stents （BMS） for patients with large coronary vessels. Methods From April 2004 to October 2006, 2407 consecutive patients undergoing de novo lesion percutaneous coronary intervention with reference vessel diameter greater than or equal to 3.5 mm at Fu Wai Hospital in Beijing, China, were prospectively enrolled into this study. We obtained 9-year clinical outcomes including death, myocardial infarction （MI）, thrombosis, target lesion revascularization （TLR）, target vessel revascularization （TVR）, and major adverse cardiac events （MACE, the composite of death, MI, and TVR）. We performed Cox＇s proportional-hazards models to assess relative risks of all the outcome measures after propensity match. Results After propensity scoring, 514 DES-treated patients were matched to 514 BMS-treated patients. The patients treated with BMS were associated with higher risk ofTLR （HR： 2.55, 95%CI： 1.520-4.277, P = 0.0004） and TVR （HR： 1.889, 95%CI： 1.185-3.011, P = 0.0075）, but the rates of death/MI and MACE were not statistically different. All Academic Research Consortium definition stent thrombosis at 9-year were comparable in the two groups. Conclusions During long-term follow-up through nine years, use of DES in patients with large coronary arteries was still associated with significant reductions in the risks of TLR and TVR.

The Use of Anti-Platelet and/or Anticoagulant Agents in the Prevention of Large Vessel Vasculitis-Associated Ischemic Complications: A Meta-Analysis

Objective: To determine the effectiveness of antiplatelet and/or anticoagulant therapy (AP/AC) at reducing ischemic events in patients with Large Vessel Vasculitis (LVV). Methods: We performed a random effects meta-analysis of studies examining antiplatelet and/or anticoagulant therapy (AP/AC) and ischemic events in Takayasu’s Arteritis (TAK) or Giant Cell Arteritis (GCA). Severe ischemic events were defined as stroke, ischemic ocular manifestations and claudication symptoms. Any ischemic event included jaw claudication in addition to the above manifestations. Results: Seven studies met inclusion criteria: 1 TAK and 6 GCA. The majority of patients (>80%) were treated with ASA and treatment was initiated prior to diagnosis of LVV. Risk of severe and any ischemic event in patients with LVV treated with AP/AC versus no treatment was not significantly different (OR 0.570, 95% CI 0.243, 1.340 and OR 0.594, 95% CI 0.248, 1.421, respectively). For studies with follow-up data (26-76 months), AP/AC was protective for severe ischemic events (OR 0.18, 95% CI 0.04, 0.83). Findings were similar when excluding studies that did not account for potential confounders, such as cardiovascular risk factors. Conclusion: At follow-up, antiplatelet therapy significantly decreases ischemic events in patients with LVV. However, in most cases of GCA, the treatment was initiated prior to the diagnosis of vasculitis. The benefit of initiating anti-platelet therapy at the time of GCA diagnosis remains unclear.

Large vessel vasculitis with rare presentation of acute rhabdomyolysis:A case report and review of literature

BACKGROUND Musculoskeletal involvement in primary large vessel vasculitis(LVV),including giant cell arteritis and Takayasu's arteritis(TAK),tends to be subacute.With the progression of arterial disease,patients may develop polyarthralgia and myalgias,mainly involving muscle stiffness,limb/jaw claudication,cold/swelling extremities,etc.Acute development of rhabdomyolysis in addition to aortic aneurysm is uncommon in LVV.Herein,we report a rare case of LVV with the first presentation of acute rhabdomyolysis.CASE SUMMARY A 70-year-old Asian woman suffering from long-term low back pain was hospitalized due to limb claudication,dark urine and an elevated creatine kinase(CK)level.After treatment with fluid resuscitation and antibiotics,the patient remained febrile.Her workup showed persistent elevated levels of inflammatory markers,and imaging studies revealed an aortic aneurysm.A decreasing CK was evidently combined with elevated inflammatory markers and negativity for antineutrophilic cytoplasmic antibodies.LVV was suspected and confirmed by magnetic resonance angiography and positron emission tomography with 18Ffluorodeoxyglucose/computed tomography.With a favourable response to immunosuppressive treatment,her symptoms resolved,and clinical remission was achieved one month later.However,after failing to follow the tapering schedule,the patient was readministered 25 mg/d prednisolone due to disease relapse.Follow-up examinations showed decreased inflammatory markers and substantial improvement in artery lesions after 6 mo of treatment.At the twelvemonth follow-up,she was clinically stable and maintained on corticosteroid therapy.CONCLUSION An exceptional presentation of LVV with acute rhabdomyolysis is described in this case,which exhibited a good response to immunosuppressive therapy,suggesting consideration for a differential diagnosis when evaluating febrile patients with myalgia and elevated CK.Timely use of high-dose steroids until a diagnosis is established may yield a favourable outcome.

Analysis on Endovascular Therapy for Acute Ischemic Stroke with Large Vessel Occlusion and Large-Scaled Core Infarct Volume in the Time Window

Patients who received endovascular therapy (EVT) for acute ischemic stroke with large vessel occlusion (AIS-LVO) and large-scaled core infarct volume in the time window were analyzed. Literature data were reviewed. Results showed that although EVT is the first choice to AIS-LVO, patients often have poor prognosis. Alberta stroke program early CT score (ASPECTS) based on computerized tomography angiography source image (CTA-SI) can reflect the real cerebral perfusion more truly, and it can assess the size of core infarct more quickly and accurately, thus enabling to judge prognosis.

Endovascular Application of Magnetic Resonance Double Mismatch Technique for Acute Anterior Circulation Large Vessel Occlusion with Cerebral Infarction in an Unknown Time Window

Objective:To investigate the clinical effects of applying the magnetic resonance double mismatch technique to endovascular treatment of acute anterior circulation,large vessel occlusion with cerebral infarction in an unknown time window.Methods:The research work was carried out in our hospital,the work was carried out from November 2018 to November 2019,the patients with acute anterior circulation large vessel occlusion with cerebral infarction who were treated in our hospital during this period,100 patients,50 patients with an unknown time window and 50 patients with definite time window were selected,and they were named as the experimental and control groups,given different examination methods,were given to investigate the clinical treatment effect.Results:Patients’data on HIHSS score before treatment,the incidence of intracranial hemorrhage and rate of Mrs≤2 rating after 90 days of treatment were not significantly different(P>0.05),which was not meaningful.The differences in data between the two groups concerning HIHSS scores were relatively significant before,and after treatment(P<0.05).Conclusion:The magnetic resonance double mismatch technique will be applied in the endovascular treatment of acute anterior circulation large vessel occlusion with cerebral infarction of unknown time window.

Application of Frontotemporal Expanded Flap with Bilateral Superficial temporal vessels in Repair of Large Area Scar Contracture in Face and Neck

Objective To summarize the clinical experience of frontotemporal expanded flap with bilateral superficial temporal vessels in repairing large area scar contracture in face and neck.Methods 14 patients with facial and Cervical scar contracture in our hospital were taken as the research object.With bilateral superficial temporal vessels as pedicles,a 400-600 ml skin dilator was inserted into the forehead and 50-100 ml skin dilator was inserted into the two temporal parts respectively.Within 3-4 months,the water injection volume reaches 2 times of the dilator volume.After maintaining for one month,skin flap transplantation was performed.The frontal flap was reserved for hairline reconstruction,and the flap was cut to cover the area after facial and Cervical scar release to reconstruct the jaw-neck angle.The pedicle division and pedicle trimming were performed 3-4 weeks after operation.Results All the 14 patients completed the operation successfully.The flap expansion time is 5-6 months.The expanded skin flap covers an area of 26 cm×9 cm-42 cm×16 cm,and all the skin flaps survived after operation.Among them,2 patients suffered from flap congestion after flap transplantation.Follow-up for 6-12 months showed that the color and texture of the skin flap were similar to those of facial skin,with natural transition and no obvious bloating.The angle between the lower jaw and the neck is about 90.The anterior flexion,posterior extension,lateral flexion and rotation of the neck are obviously improved compared with the anterior,and the posterior extension is close to normal.Conclusion Frontotemporal expanded flap with bilateral superficial temporal vessels is suitable for patients with large-area scar contracture in face and neck that cannot be repaired after expansion of adjacent local normal tissues.

Comprehensive Marine Observing Experiment Based on High-Altitude Large Unmanned Aerial Vehicle(South China Sea Experiment2020 of the “Petrel Project”)

In collaboration with 12 other institutions, the Meteorological Observation Center of the China Meteorological Administration undertook a comprehensive marine observation experiment in the South China Sea using the Yilong-10 high-altitude large unmanned aerial vehicle(UAV). The Yilong-10 UAV carried a self-developed dropsonde system and a millimeter-wave cloud radar system. In addition, a solar-powered unmanned surface vessel and two drifting buoys were used. The experiment was further supported by an intelligent, reciprocating horizontal drifting radiosonde system that was deployed from the Sansha Meteorological Observing Station, with the intent of producing a stereoscopic observation over the South China Sea. Comprehensive three-dimensional observations were collected using the system from 31 July to2 August, 2020. This information was used to investigate the formation and development processes of Typhoon Sinlaku(2020). The data contain measurements of 21 oceanic and meteorological parameters acquired by the five devices, along with video footage from the UAV. The data proved very helpful in determining the actual location and intensity of Typhoon Sinlaku(2020). The experiment demonstrates the feasibility of using a high-altitude, large UAV to fill in the gaps between operational meteorological observations of marine areas and typhoons near China, and marks a milestone for the use of such data for analyzing the structure and impact of a typhoon in the South China Sea. It also demonstrates the potential for establishing operational UAV meteorological observing systems in the future, and the assimilation of such data into numerical weather prediction models.

介入溶栓治疗颅内大血管狭窄急性闭塞致脑梗死的疗效及对患者血清BDNF GAP-43和NGF的影响

目的 探讨介入溶栓治疗颅内大血管狭窄急性闭塞致脑梗死的临床疗效及对患者血清脑源性神经营养因子(BDNF)、神经生长相关蛋白43(GAP-43)和神经生长因子(NGF)水平的影响。方法 将56例颅内大血管狭窄急性闭塞致脑梗死患者按治疗方法分为对照组(28例)和研究组(28例)。对照组患者给予常规治疗,研究组患者在对照组基础上给予介入溶栓治疗。比较两组临床疗效以及不良事件发生率,比较治疗前后两组患者美国国立卫生研究院卒中量表(NHISS)评分、脑血流灌注指标、生存质量综合评定问卷简表(WHOQOL-BREF)评分及血清BDNF、GAP-43和NGF水平。结果 治疗后两组患者NHISS评分均较治疗前降低,且研究组低于对照组(P<0.01);治疗后两组患者脑血流量(CBF)、脑血容量(CBV)、脑血流平均通过时间(MTT)均较治疗前升高,且研究组高于对照组(P<0.01)。治疗后,研究组患者WHOQDL-BREF各维度评分均高于对照组(P<0.01)。治疗后,两组患者血清BDNF、GAP-43和NGF水平均较治疗前升高,且研究组高于对照组(P<0.01)。研究组患者临床总有效率高于对照组(P<0.05),两组患者不良事件发生率比较差异无统计学意义(P>0.05)。结论 介入溶栓治疗颅内大血管狭窄急性闭塞致脑梗死能够显著改善患者神经缺损程度,改善脑部供血,提高其生活质量,疗效显著。

五种院前卒中筛查量表对院内急性大血管闭塞性缺血性卒中的预测价值

目的探讨并分析5种院前卒中筛查量表对院内急性大血管闭塞性缺血性卒中的预测价值。方法回顾性纳入2015年1月—2022年12月,因非卒中相关疾病收入东台市人民医院并在住院期间因疑似卒中症状激活院内卒中绿色通道的所有患者。采用ROC曲线评估筛查量表对院内急性大血管闭塞性缺血性卒中的预测价值。5种筛查量表分别为卒中现场评估和分类转运量表(field assessment stroke triage for emergency destination,FAST-ED)、快速动脉闭塞评估量表(rapid arterial occlusion evaluation,RACE)、洛杉矶运动量表(Los Angeles motor scale,LAMS)、辛辛那提院前卒中严重程度量表(Cincinnati prehospital stroke severity scale,CPSSS)和院前急性卒中严重程度量表(prehospital acute stroke severity scale,PASS)。结果本研究共纳入174例患者,其中54例(31.0%)患者诊断为急性大血管闭塞性缺血性卒中。RACE(AUC 0.888,95%CI 0.849~0.928)和LAMS(AUC 0.859,95%CI 0.812~0.905)对急性大血管闭塞性缺血性卒中的预测效能最高,其次是FAST-ED(AUC 0.820,95%CI 0.768~0.872)、CPSSS(AUC 0.810,95%CI 0.756~0.863)和PASS(AUC 0.786,95%CI 0.727~0.844),三者之间差异无统计学意义。结论院前卒中筛查量表在预测院内急性大血管闭塞性缺血性卒中方面均显示出良好的预测能力,其中RACE和LAMS的预测效能最高。

国和一号关键核安全技术研发

基于当前各类能源技术基础和核电技术发展水平判断,核能是社会清洁低碳转型与可持续发展的重要支撑,高安全高可靠性的大型先进压水堆核电机组是未来30年内的主力机型。本文围绕大型先进压水堆核电站国家科技重大专项所面临的重大挑战,主要阐述了通过解决“高功率核燃料冷却难”“超高温熔融物滞留难”和“高温高压高放射性包容难”三大关键技术难题,来保证从设计上消除大规模放射性释放可能性或进一步降低核电批量化建设的核安全风险。

基于ANSYS Workbench稳定性分析的大型真空容器优化设计

真空容器是石油、化工等行业中常见的设备之一,与内压容器不同,真空容器往往发生的是稳定性破坏。文中首先采用有限元软件ANSYS Workbench对DN22000 mm的真空容器进行了特征值屈曲分析,结果表明:其外压承载系数为17.427,远大于外压安全系数2.5。进而采用Response Surface Optimization模块对该真空容器进行优化设计,分析了外压承载系数、容器质量随穹顶壁厚和筒体壁厚的变化规律,以及外压承载系数、容器质量、应力随穹顶辐射筋数量的变化规律。最终确定穹顶壁厚取20 mm、筒体壁厚取22 mm、穹顶辐射筋取16个,优化后结构较最初结构质量减小了83140 kg,减小了17.02%,并且稳定性满足ASME规范要求,实现了容器轻量化的设计目标,从而显著降低制造成本。

急性前循环大血管狭窄脑卒中患者不良预后的危险因素分析

目的分析急性前循环大血管狭窄脑卒中患者不良预后的危险因素。方法回顾性选取2021-01—2023-09安庆一一六医院收治的急性前循环大血管狭窄脑卒中患者,将其中治疗后3个月随访评估为不良预后的23例患者纳入预后不良组,采用倾向匹配法从良好预后的患者中匹配46例患者纳入良好组。对比并分析2组患者的临床资料,构建风险模型。结果基线NIHSS评分≥13.705分、梗死核心区体积≥52.720 mL、入院收缩压≥160.060 mmHg为ALVSS患者不良预后的危险因素。rLMC评分≤9.429分为不良预后的保护因素,对于ALVSS患者不良预后具有中等评估价值(0.7<AUC≤0.9,P<0.05)。危险因素与保护因素联合构建的风险模型对于ALVSS患者不良预后具有较高的预估价值(AUC>0.9,P<0.05)。结论基线NIHSS偏高、梗死核心区体积较大、入院收缩压较高以及rLMC评分较低可提示急性前循环大血管狭窄脑卒中患者不良预后,可针对性给予干预,改善患者预后。

大壁厚不锈钢复合板压力容器建造关键技术及应用

在大壁厚不锈钢复合板压力容器的建造过程中,通过深入研究其技术要点和难点,优化焊接接头结构设计,成功形成了一套完整的新型建造关键技术。这套技术不仅优化了焊接接头结构,还创新了一系列施工方法,包括筒体加热卷制、接头坡口机加工、接管内壁耐蚀层TIG/FCAW自动堆焊、不锈钢衬管液氮冷套、球形封头内壁耐蚀层带极埋弧堆焊、纵环缝窄间隙埋弧自动焊以及管口接头马鞍型埋弧焊等。这些新型建造关键技术的应用,在提高压力容器质量效果的同时,也带来了显著的经济效益,为行业同类型设备的建造提供借鉴。在未来的研究中,可以进一步探索这些技术在其他领域的应用,以实现更广泛的技术交流和合作。同时,对于大壁厚不锈钢复合板压力容器的建造,仍需不断深入研究其材料特性、工艺参数和施工方法,以不断提高设备的性能和安全性。

大型集装箱船甲醇燃料舱结构设计

针对甲醇作为船舶替代燃料的特点,提出一种适用于大型集装箱船的甲醇燃料舱设计方案,以一艘大型集装箱船为例,采用有限元方法来验证甲醇燃料舱区域的结构强度,同时探讨燃料舱端部节点设计对船体结构强度的影响。为大型集装箱船甲醇燃料舱的结构设计提供参考。

急性颅内大血管闭塞性脑梗死患者血栓病理对机械取栓后出血转化的影响

目的:分析急性颅内大血管闭塞性脑梗死患者血栓病理对机械取栓后出血转化的影响。方法:收集2020年6月~2022年5月太和县人民医院收治的145例急性颅内大血管闭塞性脑梗死患者的临床资料。依据机械取栓后出血转化情况分为出血转化组和非出血转化组,比较两组基线资料及血栓病理,并分析影响急性颅内大血管闭塞性脑梗死患者机械取栓后出血转化的血栓病理因素。结果:145例急性颅内大血管闭塞性脑梗死患者中,30例(20.69%)机械取栓后发生出血转化。出血转化组患者入院时NIHSS评分、多次取栓及血栓病理为红细胞富集占比高于非出血转化组(P<0.05),并与机械取栓后出血转化均呈正相关(P<0.05)。多因素Logistic回归分析显示,入院时NIHSS评分高、多次取栓、血栓病理为红细胞富集均是急性颅内大血管闭塞性脑梗死患者机械取栓后出血转化的危险因素(P<0.05)。结论:急性颅内大血管闭塞性脑梗死患者血栓病理为红细胞富集会增加机械取栓后出血转化风险。