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1.
目的 多样的环境因素使得不同产地栽培滇重楼的化学成分也丰富多样,不同居群栽培滇重楼的甾体皂苷类成分具有很大的差异,多源数据融合分析能更全面的表征药材化学信息,建立一个高效而准确的产地鉴别模型,为其资源合理开发利用提供依据。方法 以来自云南和四川的8个产地(保山、楚雄、大理、红河、丽江、成都、文山、玉溪)共366份栽培滇重楼根茎为实验材料,采集其傅里叶变换近红外光谱(FT-NIR)和衰减全反射-傅里叶变换中红外光谱(ATR-FTMIR)数据。采用Kennard-Stone算法将不同产地的样品分为2/3的训练集和1/3的预测集,基于4种特征变量提取方法(CARS、VIP、SPA、SO-Covsel)结合2种数据融合策略(低级数据融合和中级数据融合),建立偏最小二乘产地判别分析模型。根据模型参数交叉验证均方根误差(RMSECV)和预测均方根误差(RMSEP)评估模型的稳定性,模型训练集和预测集准确率(ACC)评估模型分类性能。结果 近红外光谱和中红外光谱均能反应不同产地栽培滇重楼的化学成分差异,在中级数据融合中,基于VIP和SPA提取的特征变量建立的模型正确率均大于94%。相较于中级数据融合,低级数据融合模型得到了最为满意的结果,其预测集分类正确率达到100%。结论 根据近红外和中红外数据建立的低级数据融合PLS-DA模型,能够用于栽培滇重楼的产地鉴别分析。 相似文献
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《Neuromodulation》2021,24(8):1336-1340
BackgroundThe use of implantable pulse generators (IPG) for spinal cord stimulation (SCS) in patients with chronic pain has been well established. Although IPG-related complications have been reported on, the association between IPG site and SCS complications has not been well studied.ObjectiveTo investigate whether IPG placement site in buttock or flank is associated with SCS complications and, hence, revision surgeries.MethodA retrospective cohort study was performed that included 330 patients (52% female) treated at a single institution who underwent permanent implantation of an SCS system between 2014 and 2018. Patients ranged between 20 and 94 years of age (mean: 57.54 ± 13.25). Statistical analyses were conducted using IBM SPSS Statistics. Tests included independent samples t test, chi-square test, Mann–Whitney U test, Spearman’s rank correlation coefficient, and logistic regression.ResultsThere was a total of 93 revision surgeries (rate of 28%), where 71 out of 330 patients (rate of 21.5%) had had at least one revision surgery. Univariate tests demonstrated a significant association between IPG site and revision surgeries (p = 0.028 [chi-square test] and p = 0.031 [Mann–Whitney U test]); however, multivariate logistic regression demonstrated that neither IPG site was more likely than the other to require revision surgeries (p = 0.286).ConclusionAlthough this study found a significant association between IPG site and revision surgeries, the effect of IPG site was not found to be predictive. The IPG site likely influences whether a patient will require revision surgery, but further investigation is required to establish this association. 相似文献
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刘光 ' target='_blank'> 刘支娜 ' target='_blank'> 张玲 ' target='_blank'> 王会瑟 ' target='_blank'> 蔺颐 ' target='_blank'> 张亚涛 ' target='_blank'> 陶金 ' target='_blank'> 刘闯 ' target='_blank'> 《现代肿瘤医学》2021,(2):323-326
目的:探讨基于脉压变异度(PPV)的目标导向液体治疗(GDFT)在腹膜后巨大恶性肿瘤切除术患儿中的应用。方法:择期行腹膜后巨大恶性肿瘤切除术患儿64例,年龄0.5~3岁,ASA Ⅱ-Ⅲ级。随机将患儿分为目标导向液体治疗组(G组)和常规液体治疗组(C组),每组32例。G组以PPV为指导,根据GDFT方案进行液体管理,C组采用常规液体管理。记录手术开始(T1)、手术开始后1 h(T2)、手术结束(T3)的MAP、CVP、PPV、Lac值、TNF-α、IL-6浓度。记录术中输注晶体液量、胶体液量、液体总量、出血量、尿量、手术时间、多巴胺使用率以及排气时间、术后住院时间和恶心呕吐发生率。结果:G组输注晶体液量显著少于C组(P<0.05),而输注胶体液量显著多于C组(P<0.05)。两组术中输注液体总量、出血量、尿量与多巴胺使用率方面差异无统计学意义。T2、T3时刻,G组PPV、TNF-α、IL-6显著低于C组(P<0.05),而两组间MAP、CVP、Lac在各时点差异无统计学意义。G组术后排气时间明显短于C组(P<0.05),而在术后恶心呕吐发生率和住院时间方面两组差异无统计学意义。结论:PPV指导的GDFT可以应用于腹膜后巨大恶性肿瘤切除术患儿,能维持其血流动力学稳定,减少炎症因子IL-6、TNF-α释放,促进胃肠功能恢复,但对术后转归无明显影响。 相似文献
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Could non-HDL-cholesterol be a better marker of atherogenic dyslipidemia in obstructive sleep apnea?
《Sleep medicine》2021
Background/objectiveObstructive sleep apnea (OSA) is independently associated with dyslipidemia, a surrogate marker of atherosclerosis. Low-density lipoprotein (LDL)-cholesterol is accepted as a major independent risk factor for cardiovascular disease. However, non-high-density lipoprotein (HDL)-cholesterol is a better marker of atherogenic dyslipidemia and recommended as a target of lipid lowering therapy. We aimed to assess the prevalence of atherogenic dyslipidemia, and relationship between OSA severity and serum LDL-cholesterol and non-HDL cholesterol levels in OSA patients.MethodsWe retrospectively evaluated treatment naïve 2361 subjects admitted to the sleep laboratory of a university hospital for polysomnography. All subjects’ lipid profile including total cholesterol, LDL-cholesterol, HDL-cholesterol, triglycerides, and non-HDL-cholesterol were measured.ResultsOut of 2361 patients (mean age 49.6 ± 11.9 years; 68.9% male, apnea-hypopnea index 36.6 ± 28.4/h), 185 (7.8%) had no OSA and 2176 (92.2%) had OSA. Atherogenic dyslipidemia prevalence was high (57–66%) in OSA patients, and especially increased in severe OSA compared to other groups (p < 0.05). Though total and LDL-cholesterol did not differ between those with and without OSA, non-HDL-cholesterol (p = 0.020), and triglycerides (p = 0.001) were higher and HDL-cholesterol levels (p = 0.018) were lower in OSA patients than non-OSA. Non-HDL-cholesterol was significantly correlated with OSA severity (p < 0.001) and hypoxia parameters (p < 0.01), whereas LDL-cholesterol showed no correlation.ConclusionsAtherogenic dyslipidemia is highly prevalent and non-HDL-cholesterol levels are significantly increased, predominantly in severe OSA patients. Non-HDL-cholesterol but not LDL-cholesterol, is significantly correlated with OSA severity and hypoxia parameters. Therefore, it could be better to use non-HDL-cholesterol, which is a guideline recommended target of lipid therapy, as a marker of atherosclerotic cardiovascular risk in OSA patients. 相似文献
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M. D. Wiles A. El-Nayal G. Elton M. Malaj J. Winterbottom C. Gillies I. K. Moppett K. Bauchmuller 《Anaesthesia》2022,77(2):143-152
Pulse oximetry is used widely to titrate oxygen therapy and for triage in patients who are critically ill. However, there are concerns regarding the accuracy of pulse oximetry in patients with COVID-19 pneumonitis and in patients who have a greater degree of skin pigmentation. We aimed to determine the impact of patient ethnicity on the accuracy of peripheral pulse oximetry in patients who were critically ill with COVID-19 pneumonitis by conducting a retrospective observational study comparing paired measurements of arterial oxygen saturation measured by co-oximetry on arterial blood gas analysis (SaO2) and the corresponding peripheral oxygenation saturation measured by pulse oximetry (SpO2). Bias was calculated as the mean difference between SaO2 and SpO2 measurements and limits of agreement were calculated as bias ±1.96 SD. Data from 194 patients (135 White ethnic origin, 34 Asian ethnic origin, 19 Black ethnic origin and 6 other ethnic origin) were analysed consisting of 6216 paired SaO2 and SpO2 measurements. Bias (limits of agreement) between SaO2 and SpO2 measurements was 0.05% (−2.21–2.30). Patient ethnicity did not alter this to a clinically significant degree: 0.28% (1.79–2.35), −0.33% (−2.47–2.35) and −0.75% (−3.47–1.97) for patients of White, Asian and Black ethnic origin, respectively. In patients with COVID-19 pneumonitis, SpO2 measurements showed a level of agreement with SaO2 values that was in line with previous work, and this was not affected by patient ethnicity. 相似文献
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《Journal of vascular and interventional radiology : JVIR》2019,30(8):1265-1272
PurposeTo evaluate the safety and efficacy of balloon pulmonary angioplasty (BPA) for nonoperable chronic thromboembolic pulmonary hypertension (CTEPH) patients during the initial experience of a single center.MethodsA total of 18 CTEPH patients (5 with residual pulmonary hypertension after pulmonary endarterectomy) were treated with BPA during the period 2014–2018 and were retrospectively reviewed. Mean age was 61 ± 19 years; 55% were female; mean pulmonary artery pressure was 44 ± 12 mmHg; cardiac output was 4.3 ± 1.0 l/min; and pulmonary vascular resistance was 8.4 ± 3.6 WU. Patients were evaluated by New York Heart Association functional class, 6-minute walk distance, N-terminal pro b-type natriuretic peptide, echocardiography, right heart catheterization, and before and after completions of BPA.ResultsA total of 91 procedures were performed, with a median number of 4 BPA sessions per patient (range, 2–8). There were no deaths or major complications requiring extracorporeal support or (non)invasive ventilation. The most common complication was self-limiting hemoptysis (3%). According to Society of Interventional Radiology classification, 4 mild, 4 moderate, and 1 severe adverse events were noted. Invasive hemodynamics significantly improved, with a cardiac index increase of 15% (P = .0333), decrease of mean pulmonary artery pressure of 30% (P = .0013), and decrease of pulmonary vascular resistance of 45% (P = .0048). Stroke volume index (P = .0171) and pulmonary arterial compliance (P = .0004) were also significantly enhanced.ConclusionsBPA significantly improves cardiopulmonary hemodynamics with an acceptable safety profile. Further studies assessing the long-term efficacy of BPA are required. 相似文献
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Proteomic genotyping detects single amino acid polymorphisms to infer the genotype of corresponding non-synonymous SNPs. Like any DNA genotype, these inferences can be used to estimate random match probability. Fingermarks are a common source of biological evidence that is sample limited and a highly variable source of identifying DNA. Genetically variant peptides from fingermarks, that contain single amino acid polymorphisms, are an additional source of identifying genetic information. To discover these peptide biomarkers epidermal corneocytes from 9 subjects were isolated, processed, digested with trypsin and applied to mass spectrometry. The resulting proteomic and matching exome datasets were used to discover, characterize and validate 60 genetically variant peptides. An average of 28.8 ± 4.4 genetically variant peptides were detected from each subject resulting in a total of 264 SNP allele inferences with 260 true and 4 false positives, a false discovery rate of 1.5%. Random match probabilities were estimated using the genotype frequencies from the matching major populations in the 1000 Genomes Project. Estimates ranged up to a value of 1 in 1.7 × 108, with a median probability of 1 in 2.4 × 106. Furthermore, the proteomically-inferred genotypes are likely to be compatible with the STR-based random match probability estimates since the closest STR locus was 2.2 Mb from the nearest GVP-inferred SNP. This project represents a novel mode of genetic information that can be obtained from fingermarks and has the potential to complement other methods of human identification including analysis of ridge patterns or touch DNA. 相似文献