Evaluation of Prophylaxis with Norfloxacin and Ceftriaxone versus Ciprofloxacin during the Period of Neutropenia after Haematopoietic Stem Cell Transplantation:Retrospective Analysis of Two Sequencial Cohorts

Background: The aim of this study was to evaluate the occurrence of febrile neutropenia (FN) during aplasia after haematopoietic stem cell transplantation (HSCT) in patients who received anti-bacterial prophylaxis with norfloxacin/ceftriaxone or ciprofloxacin, between September 2006 and May 2009. Methods: We retrospectively examined all patients undergoing HSCT at S?o Paulo Hospital during the study period. Results: Of the 107 studied patients, 71 (66.3%) were included in the analysis. The exclusion criteria were as follows: occurrence of fever or infection before the transplantation (17), prophylactic use of norfloxacin (6), fever of probable non-infectious aetiology (2), and absence of prophylaxis during the aplasia period (11). Thirty-eight patients received norfloxacin and ceftriaxone as prophylaxis (Group I) and 33 received ciprofloxacin (Group II). The groups were comparable with respect to age, underlying diseases, comorbidities, and status of the underlying disease. Patients in Group II used antibiotics in a significantly higher frequency than those in Group I (66.7% vs 33.8%, p = 0.017), for 30 days before transplantation. The number of previous hospitalisations, length of hospitalisation until transplantation, type of transplant, progenitor cells used, number of CD34 cells infused, type of conditioning, and graft-versus-host disease prophylaxis were similar in both groups. After the transplantation, 28.9% and 39.4% of the patients in Groups I and II, respectively, presented Grade III and IV mucositis (p = 0.448). Neutropenia of <500 neutrophils/mm3 lasted an average of 9.5 and 9.3 days in Groups I and II, whereas neutropenia of <100 neutrophils/mm3 lasted between 6.6 and 5.7 days. FN occurred in 78.9% of patients in Group I and 81.8% in Group II, with no significant difference in the classification of these episodes. Six patients (15.8%) in Group I and five (15.2%) in Group II had bacteraemia. All patients who did not receive prophylaxis developed FN. Conclusions: The high incidence and classification of FN episodes were similar between groups;however, the frequency was lower than in those patients who did not receive prophylaxis.

头孢三嗪噻肟(Ceftriaxone)治疗新生儿败血症

用瑞士Roche药厂生产的头孢三嗪噻肟(ceftriaxone)治疗新生儿败血症,剂量为40-80mg/kg/d溶于10%葡萄糖中静脉点滴用药5—17天,13例病人单用头孢三嗪噻肟治疗,其余2例先用氨苄基青霉素加新型青霉素Ⅱ10天有效,再用头孢三嗪噻肟治愈.我们将头孢三嗪噻肟治疗金黄色葡萄球菌4例和表皮葡萄球菌2例新生儿败血症的结果与氨基等苄霉素加新型青霉素Ⅱ治疗金黄色葡萄球菌12例和表皮葡萄球菌9例新生儿败血症结果做一比较,从用药至血培养阴性时间分别为7.5±0.68天和11.38±2.22天,虽然因头孢三嗪噻肟治疗例数减少,使两者差别尚未达到统计显著的程度,但是从其趋势似可看出头孢三嗪噻肟疗效为优(0.1>P>0.05).药物不良反应不大,主要为胃肠道反应和霉菌二重感染.食欲减退(2例/15例),腹泻(2例/15例),暂时性血清谷丙转氨酶轻度升高(3例/8例)均于停药后恢复正常,霉菌性口炎,肠炎(6例/15例),经抗霉菌治疗得到控制.结论为头孢三嗪噻肟是一广谱杀菌抗菌素,它可安全有效地应用于新生儿败血症的治疗.

AES-192的相关密钥飞去来器攻击和矩形攻击

相关密钥攻击是对AES十分有效的分析方法之一.在2022年亚密会上,Derbez等利用概率为2−108的10轮相关密钥飞去来器区分器给出了目前最好的AES-192的全轮攻击.本文改进了全轮AES-192的相关密钥飞去来器和矩形攻击.基于Wang等的9轮相关密钥飞去来器区分器的截断差分,本文利用飞去来器分布表(BDT)技术给出目前概率最高的10轮相关密钥飞去来器区分器,概率为2−105.92.基于该区分器,改进了全轮AES-192的相关密钥飞去来器攻击,时间、数据和存储复杂度分别为2^(121.92)、2^(121.92)和2^(90.92),与之前的结果相比时间复杂度改进了22.08.进一步,给出了全轮AES-192的相关密钥矩形攻击,时间、数据和存储复杂度分别为2^(127.9)、2^(119.5)和2^(131.5),这也是目前在选择明文模式下对全轮AES-192最好的攻击结果.

基于AES的车联网通信加密算法

随着V2X技术发展得越来越快,车辆与其他设备的通信量以及信息重要度都在急速增长,车载信息遭到攻击从而被截取或者发生泄漏的风险也相应地大大增加,因此信息交互安全性成为了一个不可避免的研究课题。本文针对车联网传输数据量大、数据加解密操作频繁等问题,通过分析经典加密算法,进而改进传统AES加密算法,使用RC4加密算法生成伪随机密钥代替AES加密算法的密钥生成模块,优化加密时间的同时提升安全性能,并开展实验验证了其加密效率以及安全性。

基于AES与ECC混合算法的计算机网络通信数据安全加密方法

为了提高通信数据在计算机网络中的安全性,提出一种基于AES与ECC混合算法的计算机网络通信数据安全加密方法。通过时域分析,得到通信数据在计算机网络边缘的频率分布情况,根据通信数据中冗余信息的密度,离散化处理通信数据内的噪声,提取出通信数据的特征向量。根据通信数据的明文空间进行加密处理,计算出待加密通信数据的密文值,将计算机网络通信数据的加密过程约束成加密函数的计算,设定通信数据安全加密的约束条件,采用AES算法加密通信数据的明文,利用ECC算法加密AES密钥,将AES与ECC结合,生成通信数据的密钥密文,实现通信数据的安全加密。实验结果表明,所提方法能够保证通信数据在计算机网络中的安全,可以将通信数据加密后的受攻击指数控制在0.1以内,提高通信数据的加密效果。

基于LSTM-AE的民机空调热交换器性能异常检测方法

空调热交换器性能异常检测技术是快速判断民机空调系统运行状态并合理安排维修任务的关键,传统的异常检测方法难以有效处理高维时序数据,无法实现系统早期故障预警。为此,本文提出了一种基于长短期记忆网络(LSTM,long-short term memory)与自编码器(AE,autoencoder)模型的无监督异常检测方法,用以识别民机空调系统异常运行状态。首先,基于民机空调系统原始传感器参数构建表征空调热交换器性能的特征监测参数;其次,构建LSTM-AE模型进行数据特征重构并计算重构误差;最后,使用孤立森林(iForest, isolation forest)进行无监督异常监测。将本文构建的无监督异常检测方法与传统方法对比,并建立模型评估指标,验证结果表明,所构建的模型方法可以对民机空调热交换器性能异常状态进行有效检测。

基于混沌序列和AES算法的数据库外层数据传输同步加密方法

为保障数据库外层数据的安全传输,提出一种基于混沌序列和AES算法的数据库外层数据传输同步加密方法。该方法结合AES算法的加密安全性和混沌序列的加密速度优势,通过加密代理服务器和应用服务器对数据库外层数据进行处理,利用混沌序列logistic映射参数初始化、混沌序列二进制量化、AES动态加密和尾端处理实现数据库外层数据传输同步加密。实验结果表明,该方法能够成功地对文本和图像数据进行加密和隐藏,同时提高加密效率,并兼顾了数据的安全性和传输效率。

基于AES算法的计算机数据库加密系统设计与实现

随着信息技术的迅猛发展,中等职业(中职)教育面临着教学资源更新和个性化教学需求的双重挑战。知识图谱是一种通过链接和整合广泛信息资源来创建、利用和分享知识的技术,能够在复杂的数据中寻找规律,为用户提供准确的信息推荐服务。研究通过分析数据库加密的常用方式和数据库透明加密(TDE)原理,设计了一套基于知识图谱的中职线上教学资源推荐系统的体系架构。系统采用高级加密标准(AES)算法加密设计保证数据安全,整合数据库提升系统效能,并详细说明了开发过程的实现。通过实验结果及分析,证明了系统的有效性和实用性,为中职教育提供了一种新的线上教学资源推荐解决方案。

Prospective comparison of prophylactic antibiotic use between intravenous moxifloxacin and ceftriaxone for high-risk patients with post-ERCP cholangitis

BACKGROUND: The use of prophylactic antibiotics before endoscopic retrograde cholangiopancreatography(ERCP) is recommended by all major international gastroenterological societies, especially in the presence of an obstructed biliary system. This study compared the occurrence rate of post-procedural complications, including cholangitis and septicemia between prophylactic intravenous moxifloxacin and ceftriaxone in patients with bile duct obstruction scheduled for therapeutic ERCP.METHODS: From November 2013 to July 2015, 86 consecutive patients with biliary obstruction with one or more factors predicting benefits of antibiotic prophylaxis prior to ERCP were included in the current randomized open-label non-inferiority trial(Clinical Trial.gov identifier NCT02098486). Intravenous moxifloxacin(400 mg/day) or ceftriaxone(2 g/day)were given 90 minutes before ERCP, and were administered for more than 3 days if the patient developed symptoms and signs of cholangitis or septicemia. Recalcitrant cholangitis was defined as persistence of cholangitis for more than 5 days after ERCP or recurrence of cholangitis within 30 days after ERCP.RESULTS: Recalcitrant cholangitis occurred in 1(2.3%) and 2(4.8%) patients receiving intravenous moxifloxacin and ceftriaxone group, respectively(P=0.612). Septicemia was noted in1(2.3%) and 1(2.4%) patient in intravenous moxifloxacin and ceftriaxone group, respectively(P=1.0). The mean hospital stay was also not significantly different between the moxifloxacin and ceftriaxone groups(8.8±7.2 vs 9.1±9.4 days, P=0.867). Antibiotic resistance of the isolated pathogens by in vitro activity assay was noted in 1(2.3%) and 2(4.8%) patients in the moxifloxacin and ceftriaxone group, respectively(P=0.612). CONCLUSION: Intravenous moxifloxacin is not inferior to intravenous ceftriaxone for the prophylactic treatment of post-ERCP cholangitis and cholangitis-associated morbidity.

Ceftriaxone-induced toxic hepatitis

Toxic hepatitis or drug-induced liver injury encompasses a spectrum of clinical disease ranging from mild biochemical abnormalities to acute liver failure.The advantages of a long half-life,wide spectrum,high tissue penetration rate,and a good safety profile,make ceftriaxone,a third-generation cephalosporin,a frequent choice in the treatment of childhood infections.Previous studies have reported a few cases of high aspartate aminotransferase and alanine aminotransferase levels,along with three cases of hepatitis caused by ceftriaxone.Here,we report a case of drug-induced toxic hepatitis in a patient who was treated with ceftriaxone for acute tonsillitis.

Comparative efficacy of levofloxacin and ceftriaxone in the treatment of community acquired pneumonia in children

Pneumonia is a common cause of mortality and morbidity in under-5 children throughout the world. Globally an estimated 156 million new episodes of pneumonia occur each year in children and 2 million children die from pneumonia each year which is 20 percent of all deaths of children under five years old. Ceftriaxone is a commonly used drug for empiric treatment of community acquired pneumonia (CAP) in children. Levofloxacin may be an adequate option for empiric therapy in treatment of CAP in children because it gives the broad spectrum activity against both bacterial and atypical pathogens causing CAP and studies suggest that it can be safely used in children. This open labeled, randomized, comparative clinical trial was carried out in the Department of Pediatrics, Sylhet MAG Osmani Medical College Hospital, Bangladesh during January, 2011 & December, 2012 to compare the efficacy of levofloxacin and ceftriaxone in the treatment CAP in children. A total 70 cases of CAP were enrolled. 35 cases were allocated to levofloxacin group and another 35 cases to ceftriaxone group. At first the study cases were selected by systematic random sampling. Group allocation to either levofloxacin or ceftriaxone group was done by lottery method. Total duration for receiving study drugs was seven days. Dose of levofloxacin was 10 mg/kg/day children ≥5 years, where as it was 10 mg/kg 12 hourly in 6 months to <5 years age groups. Dose of ceftriaxone was 75 mg/kg/day. Response to treatment was assessed initially after 3 days and also after 7 days by clinical symptoms and signs. Clinical cure rate was determined by disappearance of the clinical signs and symptoms of pneumonia and resolution of radiological findings reported at admission. Clinical responses were categorized as cured and treatment failure. 91.43% cases were cured in levofloxacin group, whereas cure rate of ceftriaxone group was 68.57% which was statistically significant (p = 0.0168). Adverse effects of levofloxacin were found as skin rash in 1 case and vomiting in 2 cases whereas skin rash was found in 1 case in ceftriaxone group. So it can be concluded that levofloxacin is more effective than ceftriaxone in the treatment of CAP in children.

ICP-AES法测定电炉渣中二氧化硅

本文研究了采用酸溶的方式消解样品,ICP-AES光谱法测定电炉渣中二氧化硅的分析方法。采用浓盐酸和浓硝酸溶解电炉尾料样品,加入氢氟酸消解二氧化硅和硼酸络合氟离子,采用ICP-AES法测定电炉尾料样品中的二氧化硅含量。二氧化硅的相对标准偏差RSD为0.35%~0.58%,加标回收率为95.6%~102.3%。方法加标回收率好,满足分析方法要求。

基于单通道AE盲源分离的结构损伤定位

声发射(acoustic emission,简称AE)能够实现复杂板状结构损伤定位,但多数AE检测定位方法仅针对单AE源的情况,而实际中复杂板状结构产生损伤时会伴随多个AE卷积混合信号。为了解决工程中多AE源定位的问题,提出一种单通道AE盲分离-模态提取定位方法。首先,对采集的AE信号进行信号降噪,使用单通道盲源分离算法分离出无回波成分的AE信号,将多源定位转为多个单源定位问题;其次,通过提取单频模态,求取声波传播速度,估计到达时间差来进行疲劳裂纹损伤定位;最后,经过计算机仿真实验和钢箱梁桥断铅半实物仿真实验,验证了方法的准确性和有效性,并通过载荷破坏AE检测实验验证了方法的实用性。结果表明,所提方法能够应用于复杂板状结构多AE源定位问题,为实际工程应用提供了可靠的依据及参考价值。

电感耦合等离子体原子发射光谱(ICP-AES)法测定真空精炼镁合金物料中铁、铜、镍

真空精炼是目前镁金属提纯的重要工艺,工艺原料及真空精炼提纯镁金属过程残留物中Fe、Cu、Ni含量的准确测定对工艺参数的优化及调整具有重要的指导作用。传统测定方法中以邻二氮杂菲分光光度法、新亚铜灵分光光度法、丁二酮肟分光光度法测定三种元素含量,结果准确,但操作繁琐,周期较长,难以满足工业生产中高效、快速测定的需要,且方法中所需的有机萃取剂对环境污染较大。选择电感耦合等离子体发射光谱(ICP-AES)法测定真空蒸馏精炼镁合金物料中Fe、Cu、Ni,系统探究溶解酸、溶解温度、溶解时间对物料溶解和测定的影响,选择盐酸(1+1)和过氧化氢溶解体系,200℃加热条件下反应20 min为最佳消解镁合金原料条件;选择王水溶解体系,200℃加热条件下反应25 min为真空精炼残留物最佳溶解条件。并探讨ICP-AES测定过程中各元素的检出限和测定下限以及共存元素的干扰情况,建立了ICP-AES法测定真空精炼提纯镁合金物料的方法。测定结果的相对标准偏差(RSD,n=11)为Fe 5.9%~11.5%、Cu 2.6%~11.8%、Ni 3.4%~11.5%,各元素加标回收率为Fe 96.4%~102%、Cu 101%~108%、Ni 103%~105%;按照建立的方法测定镁合金原料、真空精炼残留物中的铁、铜、镍,并与国家标准方法测定结果进行对比,结果相一致。实现了ICP-AES法快速、准确测定真空蒸馏精炼镁合金物料中铁、铜、镍含量,对及时、高效、准确评估真空精炼提纯镁工艺及产品具有重要意义。

AE81镁合金轧制变形显微组织演变的研究

通过重力铸造法制备了AE81稀土镁合金,并对固溶处理后的合金在300℃和350℃进行压下量分别为15%、20%、25%和30%的轧制变形。结果表明:稀土元素Ce的加入导致铸态组织中Mg_(17)Al_(12)相不连续分布,镁基体上分布的Al4Ce相以块状形貌、中空管状形貌和针状形貌存在。轧制变形后,AE81合金所产生的变形组织的体积分数随着压下量的增大而增大,当压下量增大到25%时出现了明显的动态再结晶现象,再结晶晶粒的平均尺寸主要分布在200~400nm之间,且动态再结晶区域主要分布在Al_(4)Ce相周围。同时,Mg_(17)Al_(12)析出相的体积分数随着轧制温度和压下量的增大而增大,Mg_(17)Al_(12)相在基体上的分布得到改善。

Leukocytoclastic Vasculitis Following Ceftriaxone Exposure

Leukocytoclastic vasculitis (LCV) is an immune-complex mediated inflammation of dermal capillaries and venules that can occur after infections, drugs, autoimmune disorders, neoplasms, or idiopathically. We present the case of a 59-year-old male who was treated with ceftriaxone for an abscess, S. aureus cellulitis, and osteomyelitis of his right second toe. Biopsy confirmed the diagnosis of LCV and symptoms resolved after ceftriaxone was discontinued and systemic corticosteroids were introduced.

基于FPGA的AES和ECC算法图像加密

随着数字图像的使用次数日益增多,保护机密图像数据免受未经授权的访问较为重要。针对数字图像在通信、存储和传输等领域存在的安全问题,文中基于对称算法模型和非对称算法模型的优点提出一种具有高安全性和高速度性的数字信封技术密码方案。该方案以AES(Advanced Encryption Standard)和ECC(Elliptic Curve Cryptography)为基础,经优化后用于对称密钥共享的ECC硬件架构来提高密钥的安全性。通过加入伪随机数、使用列移位替代列混淆运算以及三维S-box等方式对传统AES进行优化,在保持香农扩散和混淆原理的同时降低了时间复杂性。基于FPGA(Field Programmable Gate Array)实现AES算法的数字图像加密仿真以及性能测试。测试结果表明,所提密码方案具有快速性、高安全性和有效性等优点,能够有效地实现图像加密。

基于AES的改进视频加密测试

为了使得视频加密技术具有更加良好的加密效果,在原本AES加密算法基础上进行了创新,通过加密元素的选取、运动矢量的加密方案设计、DCT变化系数的加密方案设计三部分进行了展开分析与实验;经过后续仿真验证,密钥敏感性得到了很好的提升;视频质量方面,改进后的AES算法的RGB直方图可知其加密效果和解密还原效果良好,经过对比分析,改进后的AES算法加密的SSIM值最小、PSNR值更低,即加密效果相对更好;经过计算可知,编码时间百分比增加了0.23%,解码时间百分比增加了8.56%,对NPCR、UACI以及加密前后视频帧像素对的相关系数等参数分别测试可知,相比前人的几种加密方式,改进后视频加密安全性能最好;综上分析可知,改进后视频加密效果最好。

基于优化AE数学模型的计算机网络风险检测与评估方法

针对现有网络风险评估方法存在的精度低、偏差大等问题,提出一种基于优化AE数学模型的计算机网络风险检测与评估方法。定义风险项参数并根据风险等级确定评估结果,推导风险项处理条件并确定风险项;结合风险特征提取结果,分别求解风险性检测值与风险性评估值,进而提升计算机网络风险检测与评估的精度。实验结果表明,所提方法可将偶发性风险的传输范围控制在0~5.12×10^(15)bit,有助于合理控制偶发性风险因素,确保网络系统稳定运行。

基于AES加密的区块链节点授信与身份共识研究

节点授信和身份共识是区块链的核心,为保证区块链的运行安全,确保全网数据的一致性,提出基于AES加密的区块链节点授信与身份共识方法。在区块链环境下,收集区块链节点历史行为数据,利用AES加密生成区块链节点密钥对。综合考虑区块链节点信任度的测算结果和密钥对的生成结果,验证区块链节点身份。根据节点身份,授予节点的信任权限,实现区块链网络中节点之间快速达成身份共识。通过实证分析实验得出结论:与传统方法相比,优化设计方法下区块链节点的授信风险降低了0.41,同时节点身份验证成功率得到明显提升。