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31.
《Clinical neurophysiology》2019,130(12):2231-2237
ObjectiveThe clinical and neurophysiological characteristics of myoclonus in Angelman syndrome (AS) have been evaluated in single case or small cohorts, with contrasting results. We evaluated the features of myoclonus in a wide cohort of AS patients.MethodsWe performed polygraphic EEG-EMG recording in 24 patients with genetically confirmed AS and myoclonus. Neurophysiological investigations included jerk-locked back-averaging (JLBA), cortico-muscular coherence (CMC) and generalised partial directed coherence (GPDC). CMC and GPDC analyses were compared to those obtained from 10 healthy controls (HC).ResultsTwenty-four patients (aged 3–35 years, median 20) were evaluated. Sequences of quasi-continuous rhythmic jerks mostly occurred at alpha frequency or just below (mean 8.4 ± 1.4 Hz), without EEG correlate. JLBA did not show any clear transient preceding the jerks. CMC showed bilateral over-threshold CMC in alpha band that was prominent on the contralateral hemisphere in the patient group as compared to HC group. GPDC showed a significantly higher alpha outflow from both hemispheres toward activated muscles in the patient group, and a significantly higher beta outflow from contralateral hemisphere in the HC group.ConclusionsThese neurophysiological findings suggest a subcortical generator of myoclonus in AS.SignificanceMyoclonus in AS has not a cortical origin as previously hypothesised. 相似文献
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BackgroundDiagnostic coagulation testing is vulnerable to factors of the pre-analytical phase such as sample centrifugation. Despite this, centrifugation conditions differ widely among European laboratories. Here we use samples from patients referred for Activated partial thromboplastin time (APTT) testing to investigate if different centrifugation conditions result in platelet-poor plasma (PPP) (plasma platelet count < 10 × 109/L) and how the variation in centrifugation conditions affect APTT measurements.MethodsCentrifugation of 2000g (10 min) were compared with 3000g (10 min) using samples from patients referred for APTT testing (n = 70). Plasma platelet count and APTT were measured to investigate the influence of the centrifugation conditions. Differences were evaluated using Bland Altman Plots and Student’s t-test.ResultsCentrifugation at 3000g for 10 min produced PPP for more of the samples (64%) than centrifugation at 2000g (6%) (p < 0.001). No statistically significant difference for APTT (p = 0.265) was found for samples with APTT < 37 s while samples with prolonged APTT (>37 s) showed a statistically significant difference (p = 0.025). The Bland Altman plot did not reveal a clinically significant difference (mean difference 0.30 s/0.68%) when compared to a maximum acceptable bias of 10%.ConclusionNone of the centrifugation conditions used in this study adequately secured PPP for all samples. Despite a statistically significant difference between samples with prolonged APTT, no clinically significant difference was observed when comparing all APTT measurements. 相似文献
33.
摘 要 目的:探讨黄芪汤加减治疗慢性阻塞性肺疾病急性加重期(AECOPD)的临床疗效。方法:采用随机数字表法将166例AECOPD患者随机分为常规组和观察组各83例。常规组采用常规西医方法治疗,观察组在常规组的基础上给予黄芪汤加减治疗。观察两组治疗前后第1秒用力呼气量(FEV1)、用力肺活量(FVC)、FEV1占FVC的百分比(FEV1/FVC%)、动脉血氧分压(PaO2)、动脉血二氧化碳分压(PaCO2)、肿瘤坏死因子 α(TNF α)、白细胞介素 1β(IL 1β)、白细胞介素 6(IL 6)水平。结果:两组治疗后FEV1、FEV1/FVC、PaO2水平与治疗前相比较均显著升高(P<0.05),且观察组与同期常规组相比较均显著升高(P<0.05);两组治疗后PaCO2、TNF α、IL 1β、IL 6水平与治疗前相比较均显著降低(P<0.05),且观察组与同期常规组相比较均显著降低(P<0.05)。结论:黄芪汤加减治疗AECOPD可降低患者炎症反应水平,改善动脉血气和肺功能,提高治疗效果,值得临床应用。 相似文献
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经典名方泽泻汤的HPLC指纹图谱及多指标含量测定研究 总被引:2,自引:0,他引:2
目的建立经典名方泽泻汤的HPLC指纹图谱,结合化学模式识别技术对其进行分析,并测定泽泻汤中3种成分23-乙酰泽泻醇B、23-乙酰泽泻醇C和白术内酯Ⅲ的含量,为泽泻汤质量控制提供科学依据。方法采用Waters WAT054275C18色谱柱(250 mm×4.6 mm,5μm),以乙腈-水为流动相进行梯度洗脱,建立15批泽泻汤的HPLC指纹图谱,并采用"中药色谱指纹图谱相似度评价系统"、SPSS22.0及SIMCA14.1软件对15批泽泻汤的HPLC指纹图谱进行相似度评价及聚类分析(CA)、偏最小二乘判别分析(PLS-DA)等化学模式识别。同时测定23-乙酰泽泻醇B、23-乙酰泽泻醇C和白术内酯Ⅲ的含量。结果建立了15批泽泻汤的HPLC指纹图谱,相似度均0.94,标定了18个共有峰,指认出3个色谱峰,分别为11号峰白术内酯Ⅲ、15号峰23-乙酰泽泻醇C、16号峰23-乙酰泽泻醇B,CA和PLS-DA将15批泽泻汤样品分为2类,同时15批泽泻汤中23-乙酰泽泻醇B、23-乙酰泽泻醇C和白术内酯Ⅲ的质量分数分别为0.321~0.569、0.075~0.139、0.106~0.142 mg/g。结论 HPLC指纹图谱结合多成分同时测定的方法,快速、简便、重复性好,为泽泻汤及其制剂的质量评价提供参考。 相似文献
37.
Jian Li Olesya Grinenko John C. Mosher Jorge Gonzalez‐Martinez Richard M. Leahy Patrick Chauvel 《Human brain mapping》2020,41(2):429-441
The role of fast activity as a potential biomarker in localization of the epileptogenic zone (EZ) remains controversial due to recently reported unsatisfactory performance. We recently identified a “fingerprint” of the EZ as a time‐frequency pattern that is defined by a combination of preictal spike(s), fast oscillatory activity, and concurrent suppression of lower frequencies. Here we examine the generalizability of the fingerprint in application to an independent series of patients (11 seizure‐free and 13 non‐seizure‐free after surgery) and show that the fingerprint can also be identified in seizures with lower frequency (such as beta) oscillatory activity. In the seizure‐free group, only 5 of 47 identified EZ contacts were outside the resection. In contrast, in the non‐seizure‐free group, 104 of 142 identified EZ contacts were outside the resection. We integrated the fingerprint prediction with the subject's MR images, thus providing individualized anatomical estimates of the EZ. We show that these fingerprint‐based estimates in seizure‐free patients are almost always inside the resection. On the other hand, for a large fraction of the nonseizure‐free patients the estimated EZ was not well localized and was partially or completely outside the resection, which may explain surgical failure in such cases. We also show that when mapping fast activity alone onto MR images, the EZ was often over‐estimated, indicating a reduced discriminative ability for fast activity relative to the full fingerprint for localization of the EZ. 相似文献
38.
Introduction:Subchromosomal deletions and duplications could currently be detected by noninvasive preliminary screening (NIPS). However, NIPS is a screening test that requires further diagnosis. Here we report a fetus with an autosomal abnormality revealed by NIPS and conventional karyotype combined with copy number variations sequencing (CNV-seq) confirmed the fetus with an unbalanced translocation.Patient concern:This was the fourth pregnancy of a 30-year-old woman who underwent 2 spontaneous abortions and gave birth to a child with a normal phenotype. The woman and her husband were healthy and nonconsanguineous. NIPS indicated a repeat of about 19-Mb fragment at the region of 16q22.1-q22.4 at 17-week gestation.Diagnoses:The combination of traditional karyotype and CNV-seq could better locate the abnormal chromosomal region and further identify the source of fetal chromosomal abnormalities. Simultaneously, we evaluated the fetal morphology by ultrasound examination. The karyotype of the fetus was 46,XX,der(7)t(7;16)(p22;q23) and CNV-seq results showed an approximately 20.96-Mb duplication in 16q22.1-q24.3 (69200001-90160000) and an approximately 3.86-Mb deletion in 7p22.3-p22.2 (40001-3900000). Prenatal ultrasound revealed the fetal micrognathia. The paternal karyotype was 46,XY, t (7;16) (p22;q23), while the maternal was normal. The fetus inherited an abnormal chromosome 7 from its father.Interventions:No treatment for the fetus.Outcomes:Pregnancy was terminated.Conclusions:To our knowledge, the occurrence of de novo partial trisomy 16q (16q22.1-qter) and partial monosomy 7p (7p22.2-pter) has not previously been reported up to now. Here, we present the perinatal findings of such a case and a review of the literatures. CNV-seq combined with karyotype is a useful tool for chromosomal abnormalities indicated by NIPS. 相似文献
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Y.Q. Lin Y. Wang Y.M. Ou S.Y. Dong Y.D. Wang 《International journal of oral and maxillofacial surgery》2019,48(7):895-901
The purpose of this study was to compare the complications of patients treated for a benign parotid tumour (BPT) by extracapsular dissection (ECD) vs. partial superficial parotidectomy (PSP). A comprehensive literature investigation was conducted by searching electronic databases. A systematic review and meta-analysis of comparative studies were performed to assess ECD and PSP for the treatment of BPTs with fixed-effects models. The outcomes analysed were transient or permanent facial nerve injury, Frey syndrome, recurrence rate, infection, and salivary fistula/sialocele. A total of 1641 patients from seven studies (1120 ECD-treated and 521 PSP-treated patients) were included in this meta-analysis. Transient facial nerve injury (odds ratio (OR) = 0.28, 95% confidence interval (CI): 0.11–0.71; p = 0.008) and Frey syndrome (OR = 0.12, 95% CI: 0.03–0.48; p = 0.003) were less prevalent in the ECD group. The rates of permanent facial nerve injury (OR = 0.77, 95% CI: 0.35–1.70; p = 0.520), recurrence rate (OR = 0.17, 95% CI: 0.02–1.75; p = 0.14), infection (OR = 0.70, 95% CI: 0.07–6.67; p = 0.76), and salivary fistula/sialocele (OR = 0.40, 95% CI: 0.06–2.66; p = 0.350) were similar in both groups. Although there was a trend that ECD showed a reduced risk for complications, the present results are not sufficient to conclude that ECD is more beneficial than PSP. 相似文献