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Objective: To determine whether packed red blood cell (PRBC) transfusion affects post-prandial superior mesenteric artery blood flow velocities (SMA BFVs) in very-low birth weight (VLBW) neonates and if so, at what time point after transfusion restoration of previous SMA BFV patterns occurs.

Design/Methods: VLBW pre-term neonates, older than 14 days and tolerating bolus enteral feedings administered every 3?h were enrolled in this prospective observational study. Pulsed Doppler ultrasound was used to measure pre- and post-prandial (at 45?min) time-averaged mean, peak and end diastolic velocities (TAMV, PSV, EDV) immediately before and after 15?ml/kg of PRBC transfusion was given over 3?h; patent ductus arteriosus (PDA) status was also evaluated. Subsequent pre- and post-prandial SMA BFVs were recorded 24 and 48?h after the transfusion.

Results: Pre- and post-prandial measurements were obtained for 21 out of 25 enrolled infants. Post-prandial SMA BFVs were attenuated during the feedings immediately after transfusion; at 24 and 48?h after transfusion, changes in post-prandial SMA BFVs were similar to those measured prior to transfusion; the presence of the PDA did not affect results.

Conclusions: PRBC transfusion blunted SMA BFV responses to feedings immediately after the transfusion with normalization observed 24?h post-transfusion.  相似文献   
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Red cell exchange (RCE) is a common procedure in adults with sickle cell disease (SCD). Implantable dual lumen Vortex (DLV) ports can be used for RCE in patients with poor peripheral venous access. We performed a retrospective cohort study of RCE procedures performed in adults with SCD. The main objective of the study was to compare the inlet speed, duration of procedures and rate of complications performed through DLV ports to those performed through temporary central venous and peripheral catheters. Twenty‐nine adults with SCD underwent a total of 318 RCE procedures. Twenty adults had DLV ports placed and 218 procedures were performed using DLV ports. Mean length of follow‐up after DLV port placement was 397 ± 263 days. Six DLV ports were removed due to infection and 1 for malfunction after a mean of 171 ± 120 days. Compared to temporary central venous and peripheral catheters, DLV port procedures had a greater rate of procedural complications, a longer duration, and a lower inlet speed (all P < 0.01). When accounting for the maximum allowable inlet speed to avoid citrate toxicity, 40% of DLV port procedures were greater than 10% below maximum speed, compared to 7 and 14% of procedures performed through temporary central venous and peripheral catheters (P < 0.0001). In conclusion, DLV ports can be used for RCE in adults with SCD, albeit with more procedural complications and longer duration. The smaller internal diameter and longer catheter of DLV ports compared to temporary central venous catheters likely accounts for the differences noted. J. Clin. Apheresis 30:353–358, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
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《Drug discovery today》2022,27(6):1733-1742
Compounds that exhibit assay interference or undesirable mechanisms of bioactivity are routinely encountered in assays at various stages of drug discovery. We observed that assays for the investigation of thiol-reactive and redox-active compounds have not been collected in a comprehensive review. Here, we review these assays and subject them to experimental optimization to improve their reliability. We demonstrate the usefulness of our assay cascade by assaying a library of bioactive compounds, chemical probes, and a set of approved drugs. These high-throughput assays should complement the array of wet-lab and in silico assays during the initial stages of hit discovery campaigns to pursue only hit compounds with tractable mechanisms of action.  相似文献   
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目的探讨红参发酵产物联合长春瑞滨及顺铂化疗方案治疗晚期非小细胞肺癌患者的疗效。方法将104例晚期非小细胞肺癌患者随机分为治疗组及对照组,每组52例。对照组患者给予单纯长春瑞滨^+顺铂化疗方案,治疗组患者在对照组基础上联合应用红参发酵产物。分别在治疗前后采用疲劳症状量表(FSI)、肺癌治疗功能评价量表(FACT-L)评价两组患者疲劳症状及生活质量,并比较治疗前后两组患者血清肿瘤标志物水平、免疫功能指标水平、药物不良反应及生存情况。结果治疗前,两组患者FSI各维度评分及总分,FACT-L各维度评分及总分,细胞角质蛋白19片段抗原21-1(CYFRA21-1)、神经元特异性烯醇化酶(NSE)、癌胚抗原(CEA)、自然杀伤(NK)细胞、CD3^+、CD4^+、CD8^+、CD4^+/CD8^+水平比较,差异均无统计学意义(P﹥0.05)。治疗后,对照组患者FSI各维度评分及总分均高于治疗前及治疗组;治疗组患者生理状态、情绪状态、对疾病关注度评分及总分均高于治疗前,且生理状态、社会家庭状态、情绪状态、功能状态、对疾病关注度评分及总分均高于对照组;两组患者CEA、CYFRA21-1及NSE水平均较治疗前下降,且治疗组患者均低于对照组患者;治疗组患者NK细胞、CD3^+、CD4^+及CD4^+/CD8^+水平均较治疗前上升,且均高于对照组患者,差异均有统计学意义(P﹤0.05)。治疗组患者血液学不良反应发生例数少于对照组,差异有统计学意义(P﹤0.05)。结论红参发酵产物联合长春瑞滨及顺铂化疗方案能够有效提高晚期非小细胞肺癌患者的免疫功能及生活质量,降低血清肿瘤标志物水平,并减轻血液学不良反应。  相似文献   
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