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991.
Ni-based filler metal and Ni-Cu-based filler metal were used to obtain copper/stainless steel (Cu/SS) joints through wire-feeding laser welding. Along the SS/weld interface, there exist different grain sizes (from coarse columnar grains to fine equiaxed grains). The heat affected zone (HAZ) on the copper side consisted of two areas with different grain sizes and the size of the grain in the Cu-HAZ of the Ni-Cu-based filled joint was much smaller than that of the Ni-based filled joint. Our results showed that grain refinement at the copper/weld (Cu/weld) interface of the Ni-Cu-based filled joint was observed through high-resolution electron backscattered diffraction (EBSD). There was a hardness elevation at the Cu/weld interface of the Ni-Cu-based filled joint due to the grain refinement on the weld of the copper side. The maximum tensile strength of the Ni-Cu-based filled joint was obtained and reached 91.2% of the tensile strength of the copper base metal (Cu-BM). Joints in this study were observed to fracture in a ductile mode. Furthermore, the Ni-Cu-based filled joint exhibited a higher plastic deformation, which was primarily caused by the large deformation of the weld zone and the large deformation of the Cu-BM due to the high plasticity of the weld, which alleviated the stress concentration, as indicated by 2D-digital image correlation (DIC) test results.  相似文献   
992.
Aims/IntroductionNon‐alcoholic fatty liver disease, especially with liver fibrosis, is associated with cardiovascular diseases. The Non‐Alcoholic Fatty Liver Disease Fibrosis Score (NFS), a non‐invasive marker of advanced fibrosis, was found to be associated with cardiovascular diseases in different populations. The aim of the present study was to determine whether the NFS is associated with subclinical myocardial remodeling in type 2 diabetes patients.Materials and MethodsA cross‐sectional study was carried out in type 2 diabetes patients. The NFS derived from available parameters was calculated, and the participants were divided according to the quartiles of the NFS and grades of the NFS (low, intermediate and high). Fibrosis‐4 and Aspartate Aminotransferase to Platelet Ratio Index, another two liver fibrosis scores, were also calculated. Subclinical myocardial remodeling was examined by echocardiography, and its associations with NFS, Fibrosis‐4 and Aspartate Aminotransferase to Platelet Ratio Index were analyzed.ResultsA total of 1,878 type 2 diabetes patients were enrolled in the present study. The NFS was independently associated with sex, age, body mass index, low‐density lipoprotein cholesterol and glycated hemoglobin in type 2 diabetes patients. Parameters of subclinical myocardial remodeling including left atrial dimension, interventricular septum thickness, left ventricular end‐diastolic diameter, left ventricular end‐systolic diameter, left ventricular posterior wall thickness (LVPWT) and left ventricular mass index were all gradually increased with the increment of the NFS. Linear regression analysis further showed that the NFS was positively associated with left atrial dimension, interventricular septum thickness, left ventricular end‐diastolic diameter, left ventricular end‐systolic diameter, LVPWT and left ventricular mass index after adjustment for the confounding factors. Similarly, Fibrosis‐4 was associated with left atrial dimension, interventricular septum thickness, LVPWT and left ventricular mass index. In contrast, the Aspartate Aminotransferase to Platelet Ratio Index was only associated with LVPWT.ConclusionsNon‐invasive liver fibrosis scores, especially the NFS, are independently associated with subclinical myocardial remodeling in type 2 diabetes patients.  相似文献   
993.
BackgroundVancomycin is the treatment of choice for serious methicillin-resistant Staphylococcus aureus (MRSA) infections. Current guidelines recommend giving an initial loading dose (LD) of 25–30 mg/kg to rapidly increase the serum concentration. However, high-quality evidence for the clinical benefit of LD is lacking. Herein, we aim to examine the association between vancomycin LD and clinical outcome.MethodsA retrospective cohort study was conducted on adult patients treated for MRSA pneumonia with vancomycin in medical intensive care units from April 2016 to August 2018. MRSA pneumonia was defined by the Centers for Disease Control and National Healthcare Safety Network definition. The primary outcome was the clinical cure of pneumonia. Secondary outcome measures included time to pharmacokinetic (PK) target attainment, microbiological cure, acute kidney injury, and all-cause mortality.ResultsA total of 81 patients were included; of these 22 (27.2%) received LD. The mean initial dose was significantly higher in the LD group. Clinical cure was similar in both groups (68.2% vs. 66.1% in the LD and non-LD groups, respectively; P=0.860). No significant difference was observed in the microbiological cure, all-cause mortality, and incidence of acute kidney injury. Furthermore, no difference was observed in terms of time to PK target attainment (69.2 vs. 63.4 h in the LD and non-LD groups, respectively; P=0.624). Vancomycin minimum inhibitory concentration of <2 mg/L was identified as an independent predictive factor for clinical cure in multivariable analysis, whereas vancomycin LD was not.ConclusionsInitial LD is not associated with better clinical outcome or rapid pharmacological target attainment in critically ill patients with MRSA pneumonia. Further studies are warranted to provide better evidence for this widely recommended practice.  相似文献   
994.
A rapid biosensor for the detection of cyromazine in milk is reported based on a fluorescence quenching result. When an FAM labelled G-rich ssDNA Tcy2 is treated with cyromazine, it can form a G-quadruplex-CYR complex and cause a change in fluorescence. As a result, the presence of cyromazine can be determined by fluorescence quenching. This sensor is selective for the detection of cyromazine in raw milk and has a limit of detection of 0.68 ppb and a detection range from 0 to 200 ppb.

A rapid biosensor for the detection of cyromazine in milk is reported based on a fluorescence quenching result.  相似文献   
995.
Purpose

Pasireotide is an effective treatment for acromegaly and Cushing’s disease, although treatment-emergent hyperglycemia can occur. The objective of this study was to assess incretin-based therapy versus insulin for managing pasireotide-associated hyperglycemia uncontrolled by metformin/other permitted oral antidiabetic drugs.

Methods

Multicenter, randomized, open-label, Phase IV study comprising a core phase (≤?16-week pre-randomization period followed by 16-week randomized treatment period) and optional extension (ClinicalTrials.gov ID: NCT02060383). Adults with acromegaly (n?=?190) or Cushing’s disease (n?=?59) received long-acting (starting 40 mg IM/28 days) or subcutaneous pasireotide (starting 600 µg bid), respectively. Patients with increased fasting plasma glucose (≥?126 mg/dL on three consecutive days) during the 16-week pre-randomization period despite metformin/other oral antidiabetic drugs were randomized 1:1 to open-label incretin-based therapy (sitagliptin followed by liraglutide) or insulin for another 16 weeks. The primary objective was to evaluate the difference in mean change in HbA1c from randomization to end of core phase between incretin-based therapy and insulin treatment arms.

Results

Eighty-one (32.5%) patients were randomized to incretin-based therapy (n?=?38 received sitagliptin, n?=?28 subsequently switched to liraglutide; n?=?12 received insulin as rescue therapy) or insulin (n?=?43). Adjusted mean change in HbA1c between treatment arms was – 0.28% (95% CI – 0.63, 0.08) in favor of incretin-based therapy. The most common AE other than hyperglycemia was diarrhea (incretin-based therapy, 28.9%; insulin, 30.2%). Forty-six (18.5%) patients were managed on metformin (n?=?43)/other OAD (n?=?3), 103 (41.4%) patients did not require any oral antidiabetic drugs and 19 patients (7.6%) were receiving insulin at baseline and were not randomized.

Conclusion

Many patients receiving pasireotide do not develop hyperglycemia requiring oral antidiabetic drugs. Metformin is an effective initial treatment, followed by incretin-based therapy if needed.

ClinicalTrials.gov ID: NCT02060383.

  相似文献   
996.
997.
Park  Do-Yang  Gu  Gayoung  Han  Jang Gyu  Park  Bumhee  Kim  Hyun Jun 《Sleep & breathing》2021,25(3):1477-1485
Purpose

Positive airway pressure (PAP) devices have been widely used as the first line of treatment in obstructive sleep apnea (OSA). Most advanced PAP devices support the estimation of respiratory index (RI) using the patient’s mask airflow. In addition to the compliance factor for PAP device use, which is important for monitoring patient sleep health, RI is also becoming important for monitoring. However, there are few reports that validate RI of a PAP device with polysomnography.

Methods

Between January 2015 and December 2017, 50 participants were enrolled who were diagnosed with OSA and prescribed auto-titration PAP (APAP) devices. The RIs of participants were measured at night using APAP devices, concurrently with electroencephalography, respiratory inductance plethysmography sensors, and other polysomnographic sensors in a sleep laboratory. The respiratory-related data of APAP were prospectively analyzed with the manually scored polysomnographic data.

Results

The apnea-hypopnea index and apnea index showed a statistically close relationship between the auto-scored respiratory data from the APAP device and the manually scored respiratory data from polysomnographic sensors. Obstructive apnea and central apnea indices showed relatively low correlations. The differences between the auto-scored RI and manually scored RI were influenced by BMI, waist circumference, weight, oxygen saturation, and respiratory distress indices of diagnostic polysomnographic factors.

Conclusions

The RIs of APAP devices have a tendency to be underestimated or mismatched when compared with polysomnography. Sleep specialists are advised to consider additional anthropometric and diagnostic factors to account for these differences during PAP treatment.

  相似文献   
998.
Li  Chengzong  Ju  Weizhu  Gu  Kai  Li  Mingfang  Cui  Chang  Liu  Hailei  Wang  Zidun  Chen  Hongwu  Yang  Gang  Zhang  Fengxiang  Yang  Bing  Wang  Zhirong  Chen  Minglong 《Journal of interventional cardiac electrophysiology》2021,60(3):365-373
Purpose

Sinus node inability or conduction disorders of its surrounding atrial myocardium cause sinus node dysfunction (SND). This study aimed to characterize right atrium (RA) substrates and long-term atrial lead performance after pacemaker implantation in non-senile SND patients.

Methods

Eighteen SND patients (53.3?±?9.6 years) controlled by 18 age-matched supraventricular tachycardia patients were consecutively enrolled. The P-wave amplitude (PWA) and P-wave duration (PWD) were measured on surface electrocardiography. Electroanatomic mapping was conducted to assess the bipolar voltage, complex signals, volume, and activation time of RA. Pacemaker implantation was performed in SND patients after mapping.

Results

Compared with controls, SND patients showed significant PWA reduction (0.13?±?0.02 vs. 0.16?±?0.04 mV, p?=?0.017) and PWD prolongation (120.8?±?15.2 vs. 105.2?±?8.6 ms, p?=?0.001). The RA endocardial voltage was lower (1.56?±?0.78 vs. 2.57?±?0.55 mV, p?<?0.001) and activation time was longer (112.1?±?14.9 vs. 90.8?±?12.4 ms, p?<?0.001) in the study group. Atrial lead was anchored at the lower atrial septum in one patient and failed in another due to extensive atrial scarring. During a median follow-up of 86 (57–88) months, one patient lost atrial capturing, and overall atrial sensing was significantly decreased (2.44?±?1.16 vs. 1.87?±?1.01 mV, p?=?0.003).

Conclusions

Atrial involvement was proved and the process was progressive in non-senile SND patients, as demonstrated by diffused RA lower voltage, slower conduction, and the decrease of the atrial lead sensing.

  相似文献   
999.
目的研究2型糖尿病(T2DM)患者发生慢性肾脏病(CKD)的危险因素,并着重分析肥胖与CKD发生的关系。方法纳入2009年1月至2019年6月在南京鼓楼医院就诊的18至75岁诊断为T2DM的患者,收集一般资料包括性别、年龄、体重指数(BMI)、收缩压、舒张压、糖尿病病程以及实验室指标包括血红蛋白(Hb)、白蛋白、丙氨酸转氨酶(ALT)、天冬氨酸氨基转移酶(AST)、总胆红素(TBIL)、尿酸、空腹血糖(FPG)、糖化血红蛋白(HbA1c)、甘油三酯(TG)、总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C)、尿白蛋白/肌酐比值和估算的肾小球滤过率。肥胖定义为BMI≥28 kg/m2,超重定义为24 kg/m2≤BMI<28 kg/m2。根据是否合并CKD,将研究对象分为合并CKD组和不合并CKD组。在不合并CKD的T2DM患者中,选取至少随访一次,随访时间超过12个月且随访数据完整的患者,按是否发生CKD分为发生CKD组和未发生CKD组。两组间各指标的比较采用t检验、非参数检验以及χ2检验。采用单因素及多因素logistic回归分析法分析T2DM患者发生CKD的危险因素,采用Cox比例风险模型分析随访的T2DM患者CKD发生的危险因素。采用限制性立方样条(RCS)拟合Cox回归模型来评估不同的BMI截点与CKD的关系。结果共纳入3194例T2DM患者,其中合并CKD组620例,不合并CKD组2574例。与不合并CKD组相比,合并CKD组T2DM患者BMI明显增高(P=0.005)。单因素logistic回归分析结果显示,性别、肥胖、收缩压、舒张压、Hb、白蛋白、TG、TC、FPG及HbA1c为T2DM患者发生CKD的影响因素(均P<0.05),将上述指标作为自变量,进行多因素logistic回归分析,结果显示,肥胖(OR=1.058,95%CI 1.079~2.018),收缩压增高(OR=1.027,95%CI 1.018~1.035),TG增加(OR=1.087,95%CI 1.008~1.171),FPG增高(OR=1.042,95%CI 1.003~1.083)是T2DM患者发生CKD的影响因素(均P<0.05)。不合并CKD组中随访时间超过12个月且随访数据完整的T2DM患者共753例,其中,发生CKD组182例,未发生CKD组571例。Cox比例风险模型分析结果显示,在校正年龄、糖尿病病程、收缩压、AST、TG及FPG后,超重为发生CKD的危险因素(OR=1.95,95%CI 1.05~3.61)。RCS拟合Cox回归模型结果显示,T2DM患者BMI与CKD发生风险呈非线性关系,BMI在28~31 kg/m2的T2DM患者CKD的发生风险增加(均P<0.05)。结论T2DM患者肥胖与CKD密切相关,肥胖的T2DM患者,特别是BMI在28~31 kg/m2,容易发展为CKD。  相似文献   
1000.
目的分析血清微小核糖核酸(miR)-133a在脓毒症并发急性呼吸窘迫综合征(acute respiratory distress syndrome, ARDS)患者中的表达及与预后的关系。 方法选取2019年6月至2021年5月我院收治的65例脓毒症患者,根据是否并发ARDS,分为并发ARDS 35例和无ARDS 30例。随访28 d,统计脓毒症并发ARDS者预后,检测患者入住ICU第1天、第2天、第3天血清miR-133a水平,比较存活者和死亡者临床特征,采用Logistic回归分析判定影响脓毒症并发ARDS预后的因素,采用受试者工作曲线(ROC)分析血清miR-133a水平预测脓毒症并发ARDS者预后的价值。 结果并发ARDS入住ICU第1天、第2天、第3天血清miR-133a水平均高于无ARDS者(P<0.05);随访28 d,脓毒症并发ARDS者病死率为40.00%;死亡者入住ICU第1天、第2天、第3天血清miR-133a水平均高于存活者(P<0.05);死亡者序贯器官衰竭(SOFA)评分、血管外肺水指数、第1天血清miR-133a水平与存活者比较,差异均有统计学意义(P<0.05);Logistic多因素回归分析显示SOFA评分、第1天血清miR-133a水平均是影响脓毒症并发ARDS者死亡的危险因素(P<0.05);ROC分析显示,第1天血清miR-133a水平预测脓毒症并发ARDS者死亡的最佳截断点为1.47,灵敏度为85.71%,特异度为90.48%,AUC为0.857。 结论脓毒症并发ARDS者血清miR-133a水平升高,血清miR-133a水平是影响脓毒症并发ARDS者死亡的危险因素,监测血清miR-133a水平变化,作为预测患者预后的指标。  相似文献   
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