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1.
一测多评法(quantitative analysis of multi-components by single marker,QAMS)已成熟应用于中药材、中药提取物及中成药领域等中药复杂体系的质量评价研究中,有效解决了因对照品缺乏而导致的多指标质控技术推广难问题。本文查阅近五年的国内外研究文献,重点总结了高效液相色谱、气相色谱和质谱等技术在QAMS法中药质量控制中的应用。高效液相色谱联用紫外检测器(UV)技术应用最为广泛,最适合于中药QAMS法定量,结果稳定、准确;而高效液相色谱联用蒸发光检测器在中药QAMS法应用中,其测定准确性和适用性仍然需进一步探索和验证。液质联用技术虽然具有灵敏度高、线性范围宽等优点,但易受仪器参数、基质效应等的影响。进一步发展HPLC-UV技术在中成药制剂质量评价中的应用,是QAMS法多成分定量值得关注的方向;探索LC-MS和GC技术在中药QAMS质量评价中的稳定性和普适性是未来将面临的挑战。 相似文献
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《Clinical neurophysiology》2019,130(9):1465-1473
ObjectiveTo assess the feasibility of motor unit number index (MUNIX) in the quantitative assessment of the cervical spondylotic amyotrophy (CSA).MethodsMUNIX was recorded bilaterally on the abductor pollicis brevis, abductor digiti minimi, biceps brachii and middle deltoid in 41 normal controls and 47 patients with CSA (distal-type to proximal-type ratio: 25 to 22). Additionally, patients were assessed on handgrip strength (HGS), the disabilities of arm, shoulder and hand (DASH) and Medical Research Council (MRC) scales. These examinations were re-evaluated approximately 18 months after surgery in 37 of these CSA patients.ResultsMUNIX values were noticeably lower in the mainly affected muscles of CSA patients than those in controls (P < 0.05), and 49.0% (51/104) of the tested muscles with abnormal MUNIX measurements showed normal muscle strength. Significant correlations between MUNIX measurements and both DASH and MRC scores were observed in both CSA patient groups (P < 0.05). Postoperative longitudinal follow-up analysis identified significant increase in motor unit number in both CSA patient groups within approximately 18 months (P < 0.05), with or without improved measures of motor function.ConclusionsA significant reduction in MUNIX values related to motor impairment was observed in CSA patients, even in the subclinical stage. Compared to measures of motor function, the MUNIX measurements in the patients with CSA improved more noticeably after surgical intervention.SignificanceMUNIX may serve as an available supplementary test to quantitatively evaluate the motor dysfunction in CSA and to track its progression, that is complementary to conventional electromyography. 相似文献
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《Biomedical and environmental sciences : BES》2022,35(9):804-810
ObjectiveTo detect the Epstein-Barr virus (EBV) viral load of children after hematopoietic stem cell transplantation (HSCT) using chip digital PCR (cdPCR).MethodsThe sensitivity of cdPCR was determined using EBV plasmids and the EBV B95-8 strain. The specificity of EBV cdPCR was evaluated using the EBV B95-8 strain and other herpesviruses (herpes simplex virus 1, herpes simplex virus 2, varicella zoster virus, human cytomegalovirus, human herpesvirus 6, and human herpesvirus 7). From May 2019 to September 2020, 64 serum samples of children following HSCT were collected. EBV infection and the viral load of serum samples were detected by cdPCR. The epidemiological characteristics of EBV infections were analyzed in HSCT patients.ResultsThe limit of detection of EBV cdPCR was 110 copies/mL, and the limit of detection of EBV quantitative PCR was 327 copies/mL for the pUC57-BALF5 plasmid. The result of EBV cdPCR was up to 121 copies/mL in the EBV B95-8 strain, and both were more sensitive than that of quantitative PCR. Using cdPCR, the incidence of EBV infection was 18.75% in 64 children after HSCT. The minimum EBV viral load was 140 copies/mL, and the maximum viral load was 3,209 copies/mL using cdPCR. The average hospital stay of children with EBV infection (184 ± 91 days) was longer than that of children without EBV infection (125 ± 79 days), P = 0.026.ConclusionEBV cdPCR had good sensitivity and specificity. The incidence of EBV infection was 18.75% in 64 children after HSCT from May 2019 to September 2020. EBV cdPCR could therefore be a novel method to detect EBV viral load in children after HSCT. 相似文献
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目的 建立蒙药绿松石的质量标准。方法 收集不同产地绿松石,共10批。观察绿松石样品和粉末的性状并进行理化鉴别;按2020年版《中国药典》(四部)通则方法测定绿松石样品中水分、浸出物含量;采用原子吸收光谱法测定绿松石样品铜元素含量。结果 绿松石为不规则、周围带有黑石的块状物,表面蓝绿色,体重,质硬脆,难砸碎,断面呈贝壳状,蜡样光泽,粉末呈灰绿色,无臭,味淡;理化鉴别结果显示,呈铜盐反应;10批次样品中水分含量为0.41%-3.94%(SD=1.37%),浸出物含量为0.21%-0.81%(SD=0.21%),铜元素含量为3.03%-4.63%(SD=0.63%)。结论 初步拟定绿松石中水分含量不得超多5.0%、浸出物含量不得低于0.10%,铜元素含量应为2.60%-4.84%,制定的标准可用于蒙药材绿松石的质量控制。 相似文献
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《Clinical neurophysiology》2021,132(5):1089-1104
ObjectiveDescribe and evaluate the concepts of near fiber electromyography (NFEMG), the features used, including near fiber motor unit potential (NFMUP) duration and dispersion, which relate to motor unit distal axonal branch and muscle fiber conduction time dispersion, and NFMUP segment jitter, a new measure of the temporal variability of neuromuscular junction transmission (NMJ), and axonal branch and muscle fibre conduction for the near fibres (i.e. NF jitter), and the methods for obtaining their values.MethodsTrains of high-pass filtered motor unit potentials (MUPs) (i.e. NFMUP trains) were extracted from needle-detected EMG signals to assess changes in motor unit (MU) morphology and electrophysiology caused by neuromuscular disorders or ageing. Evaluations using simulated needle-detected EMG data were completed and example human data are presented.ResultsNFEMG feature values can be used to detect axonal sprouting, conduction slowing and NMJ transmission delay as well as changes in MU fiber diameter variability, and NF jitter. These changes can be detected prior to alterations of MU size or numbers.ConclusionsThe evaluations clearly demonstrate and the example data support that NFMUP duration and dispersion reflect MU distal axonal branching, conduction slowing and NMJ transmission delay and/or MU fiber diameter variability and that NFMUP jiggle and segment jitter reflect NF jitter.SignificanceNFEMG can detect early changes in MU morphology and/or electrophysiology and has the potential to augment clinical diagnosis and tracking of neuromuscular disorders. 相似文献
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目的探讨冠状动脉临界病变血管内超声(IVUS)检查参数与定量血流分数(QFR)的相关性。方法前瞻性连续入选2018年9月至2019年9月于同济大学附属东方医院接受QFR和IVUS检查的116例患者(117处冠状动脉临界病变)。根据QFR评估结果,将患者分为QFR≤0.80组(25处病变)和QFR>0.80组(92处病变),比较两组IVUS检查参数的差异。应用Poisson线性相关性分析以及受试者工作特征(ROC)曲线评估IVUS与QFR的相关性,应用logistic多元回归分析QFR≤0.80的预测因素。结果IVUS检查发现,QFR≤0.80组最小管腔面积(MLA)[(3.1±0.8)mm2比(3.6±1.1)mm2,P=0.040]、最小管腔直径(MLD)[(1.8±0.3)mm比(2.0±0.3)mm,P=0.012]显著小于QFR>0.80组,而斑块负荷[(73.5±5.6)%比(68.0±8.4)%,P=0.002]、面积狭窄率[(69.8±8.8)%比(63.8±9.8)%,P=0.007]、斑块偏心指数[(0.83±0.12)比(0.73±0.19),P=0.008]及回声消减斑块比例(52.0%比23.9%,P=0.003)显著高于QFR>0.80组,差异均有统计学意义。Poisson线性相关分析显示,MLA(r=0.259,P=0.005)、MLD(r=0.300,P=0.001)与QFR正相关,而斑块负荷(r=–0.357,P<0.001)以及斑块偏心指数(r=–0.247,P=0.008)与QFR负相关。logistic多因素回归分析表明斑块负荷>70%(OR 4.531,95%CI 1.443~14.222,P=0.010)和斑块偏心指数(OR 1.066,95%CI 1.014~1.121,P=0.012)为QFR≤0.80的独立预测因素。结论冠状动脉临界病变IVUS检查结果中斑块负荷>70%以及斑块偏心指数是QFR≤0.80的独立预测因子。 相似文献
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《Journal of vascular and interventional radiology : JVIR》2021,32(8):1103-1112.e12
PurposeTo investigate the feasibility, safety, and absorbed-dose distribution of prostatic artery radioembolization (RE) in a canine model.Materials and MethodsFourteen male castrated beagles received dihydroandrosterone/estradiol to induce prostatic hyperplasia for the duration of the study. Each dog underwent fluoroscopic prostatic artery catheterization. Yttrium-90 (90Y) microspheres (TheraSphere; Boston Scientific, Marlborough, Massachusetts) were delivered to 1 prostatic hemigland (dose escalation from 60 to 200 Gy), with the contralateral side serving as a control. Assessments for adverse events were performed throughout the follow-up (Common Terminology Criteria for Adverse Events v5.0). Positron emission tomography/magnetic resonance (MR) imaging provided a confirmation after the delivery of absorbed-dose distribution. MR imaging was performed before and 3, 20, and 40 days after RE. Tissue harvest of the prostate, rectum, bladder, urethra, penis, and neurovascular bundles was performed 60 days after RE.ResultsAll the animals successfully underwent RE. Positron emission tomography/MR imaging demonstrated localization to and good coverage of only the treated hemigland. No adverse events occurred. The MR imaging showed a significant dose-dependent decrease in the treated hemigland size at 40 days (25%–60%, P < .001). No extraprostatic radiographic changes were observed. Necropsy demonstrated no gross rectal, urethral, penile, or bladder changes. Histology revealed RE-induced changes in the treated prostatic tissues of the highest dose group, with gland atrophy and focal necrosis. No extraprostatic RE-related histologic findings were observed.ConclusionsProstate 90Y RE is safe and feasible in a canine model and leads to focal dose-dependent changes in the gland without inducing unwanted extraprostatic effects. These results suggest that an investigation of nonoperative prostate cancer is warranted. 相似文献