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1.
目的:提升参威骨痹片的质量标准,初步探索其质量控制指标成分在批间含量差异较大的原因。方法:采用HPLC建立参威骨痹片的指纹图谱,以Diamonsil C18(4. 6 mm×250 mm,5μm)为色谱柱,流动相乙腈(A)-0. 1%磷酸水溶液(B)梯度洗脱(0~5 min,10%A;5~15 min,10%~12%A;15~30 min,12%~26%A;30~43 min,26%~31%A,43~50 min,31%~40%A,50~70 min,40%~55%A;70~84 min,55%~72. 5%A),检测波长230 nm。以共有峰为自变量绘制正交偏最小二乘法-判别分析-变量重要性投影(OPLS-DA-VIP)图,将共有峰对该制剂各批次间指纹图谱差异的贡献度量化,寻找差异较大的色谱峰,结合相关文献,筛选出与参威骨痹片临床适应症相关的成分并进行其含量测定的专属性试验,最终选定质控指标。通过HPLC-二极管阵列检测器(DAD)同时对本品及其生产过程中间体中质控指标进行测定,检测波长236,276,230,322 nm,其他条件同HPLC指纹图谱检测方法。结果:HPLC指纹图谱共标定了26个共有峰,各批次样品指纹图谱与对照指纹图谱的相似度均≥0. 950。优选出马钱苷酸、龙胆苦苷、芍药苷、蛇床子素为参威骨痹片的质控指标,四者的平均质量分数分别为161. 02,401. 80,255. 54,80. 68μg·g-1。结论:所建立的指纹图谱及多指标定量分析方法稳定、可靠,可用于参威骨痹片的质量控制。原料药批间质控指标成分含量差异和生产过程中间体的质控方法不够完善是引起该制剂批间质控指标成分含量差异较大的主要原因。 相似文献
2.
Sabita Jiwnani Priya Ranganathan Vijaya Patil Vandana Agarwal George Karimundackal C.S. Pramesh 《The Journal of thoracic and cardiovascular surgery》2019,157(1):380-386
Objectives
Post-thoracotomy pain leads to patient discomfort, pulmonary complications, and increased analgesic use. Intercostal nerve injury during thoracotomy or its entrapment during closure can contribute to post-thoracotomy pain. We hypothesized that a modified technique of posterolateral thoracotomy and closure, preserving the intercostal neurovascular bundle, would reduce acute and chronic post-thoracotomy pain.Methods
We randomized 90 patients undergoing posterolateral thoracotomy for pulmonary resection at a tertiary level oncology center to standard posterolateral (control arm) or modified nerve-sparing thoracotomy. All patients received morphine via patient-controlled analgesia pumps. The primary outcome was the worst postoperative pain score in the first 3 postoperative days. Secondary outcomes included the average pain score and analgesic requirements in the first 3 postoperative days and the incidence of post-thoracotomy pain 6 months after surgery.Results
No significant differences were seen between the groups in acute or chronic post-thoracotomy measured by the numeric rating scale. There was no difference seen in the worst (mean) postoperative pain scores (3.71 vs 3.83, difference 0.12; 99% confidence interval [CI], ?0.7 to +0.9; P = .7), average (mean) pain scores in the first 3 postoperative days (1.77 vs 1.85, difference 0.08; 99% CI, ?0.4 to +0.6; P = .69), mean consumption of morphine (mg/kg) (1.45 vs 1.40, difference ?0.05; 99% CI, ?0.4 to +0.3; P = .73), or incidence of chronic postoperative pain (37.8% vs 40%, difference 4.9%; 99% CI, ?22.8 to +30.7%; P = .73).Conclusions
The modified nerve-sparing thoracotomy technique does not reduce post-thoracotomy pain compared with standard posterolateral thoracotomy. 相似文献3.
Chi-Chen Yeh Shih-Shan Huang Po-Yu Liu Bo-Cheng Wang Chia-Fen Tsai Der-Yuan Wang Hwei-Fang Cheng 《Yao wu shi pin fen xi = Journal of food and drug analysis.》2019,27(3):749-757
A simple gradient high-performance liquid chromatography with diode array detection (HPLC-DAD) method was used to simultaneously to analyze characteristics of six indicator compounds in the traditional Chinese medicine (TCM) formulation Wen-Qing-Yin (WQY). Separate optimization was performed using a Cosmosil C18 column gradient method with 0.1% formic acid in both mobile phases of aqueous and acetonitrile (ACN), at a flow rate, detection wavelength, and sample volume of 1.8 mL/min, 268 nm, and 10 μL, respectively. The linear regression of six active compounds berberine (BER), baicalin (BAI), ferulic acid (FER), geniposide (GEN), hydorxymethoxylfurfural (HMF), and paeoniflorin (PAE) was produced at the concentration range of 10–2000 μg/mL. The method validation revealed an acceptable precision (intra- and inter-day precision < 3.39% and 4.11%, respectively) and recovery (85.60–110.45% and 86.58–110.90%), a recovery range of 86.61–109.42%, and sensitivity (limit of detection [LOD] and limit of quantification [LOQ] values were in the range of 0.03–3.13, and 0.08–9.38 μg/mL, respectively) while the calibration curves were linear with a correlation coefficient (R2) ranging from 0.9966 to 0.9989. The qualitative and quantitative analyses were performed by direct comparison of the peaks of the WCY extract to retention times of reference standards. Additionally, principal component analysis (PCA) successfully discriminated four purchased commercial samples of all six indicator constituents, and the present results indicate their comprehensive potential usefulness for qualitative and quantitative analyses of the WQY decoction and its commercial products. 相似文献
4.
《Urologic oncology》2015,33(4):163.e15-163.e23
ObjectiveTo compare the prognostic accuracy of Prostate Health Index (PHI) and Prostate Cancer Antigen 3 in predicting pathologic features in a cohort of patients who underwent radical prostatectomy (RP) for prostate cancer (PCa).Methods and materialsWe evaluated 156 patients with biopsy-proven, clinically localized PCa who underwent RP between January 2013 and December 2013 at 2 tertiary care institutions. Blood and urinary specimens were collected before initial prostate biopsy for [-2] pro–prostate-specific antigen (PSA), its derivates, and PCA3 measurements. Univariate and multivariate logistic regression analyses were carried out to determine the variables that were potentially predictive of tumor volume >0.5 ml, pathologic Gleason sum≥7, pathologically confirmed significant PCa, extracapsular extension, and seminal vesicles invasions.ResultsOn multivariate analyses and after bootstrapping with 1,000 resampled data, the inclusion of PHI significantly increased the accuracy of a baseline multivariate model, which included patient age, total PSA, free PSA, rate of positive cores, clinical stage, prostate volume, body mass index, and biopsy Gleason score (GS), in predicting the study outcomes. Particularly, to predict tumor volume>0.5, the addition of PHI to the baseline model significantly increased predictive accuracy by 7.9% (area under the receiver operating characteristics curve [AUC] = 89.3 vs. 97.2, P>0.05), whereas PCA3 did not lead to a significant increase.Although both PHI and PCA3 significantly improved predictive accuracy to predict extracapsular extension compared with the baseline model, achieving independent predictor status (all P׳s<0.01), only PHI led to a significant improvement in the prediction of seminal vesicles invasions (AUC = 92.2, P<0.05 with a gain of 3.6%).In the subset of patients with GS≤6, PHI significantly improved predictive accuracy by 7.6% compared with the baseline model (AUC = 89.7 vs. 97.3) to predict pathologically confirmed significant PCa and by 5.9% compared with the baseline model (AUC = 83.1 vs. 89.0) to predict pathologic GS≥7. For these outcomes, PCA3 did not add incremental predictive value.ConclusionsIn a cohort of patients who underwent RP, PHI is significantly better than PCA3 in the ability to predict the presence of both more aggressive and extended PCa. 相似文献
5.
目的构建足的三维统计形状模型(statistical shape model,SSM),揭示足形状的三维变化特征。方法 50名中国青年男性正常足数据用于三维统计形状建模,通过足面网格配准、点对齐及主成分(principal component,PC)降维分析等步骤,获得平均足形态及在各PC维度标准差等参数化的足形态。结果通过PC降维分析,三维足型主要在长短及宽窄(PC1,48.01%)、足弓高度及足背厚度(PC2,11.38%)及大脚趾展收(PC3,7.48%)等维度变化。结论通过构建参数化的足三维SSM,可运用至基于该人群的鞋楦制作、鞋垫定制及临床足病快速诊断等应用。 相似文献
6.
Mario Martínez-Galdmez Miguel Schüller-Arteaga Jorge Galvn-Fernndez Vladimir Kalousek Ezequiel Petra Boris Pabn Santiago Ortega-Gutirrez Paloma Jimnez-Arribas Carlos Rodríguez-Arias 《Interventional neuroradiology》2021,27(2):230
Flow diverter devices have become a routine first-line option for treatment of an increasing population of intracranial aneurysms at many neurovascular centers. Despite the promising results of flow diverter stents on anterior circulation, incomplete occlusion on the presence of fetal posterior circulation has been described on several reports. Here we describe a novel technical alternative to conventional flow diversion approach for this specific subgroup of aneurysms using the low-profile flow diverter, Silk Vista Baby. The device was selectively placed into the fetal type posterior cerebral artery in half-T configuration for the treatment of a posterior communicating aneurysm using a transcirculation approach through the anterior communicating artery. This represents a useful and effective technique and should be considered when encountering the above-described situation. 相似文献
7.
8.
Diagnostic performance of expression of PCA3, Hepsin and miR biomarkers inejaculate in combination with serum PSA for the detection of prostate cancer 下载免费PDF全文
9.
《Urologic oncology》2015,33(5):202.e19-202.e28
ObjectiveTo evaluate the additive value of the prostate cancer gene 3 (PCA3) urine test to serum prostate-specific antigen (PSA) in prostate cancer (PC) screening among breast cancer, early-onset gene (BRCA) mutation carriers. This study was performed among the Dutch participants of IMPACT, a large international study on the effectiveness of PSA screening among BRCA mutation carriers.Materials and methodsUrinary PCA3 was measured in 191 BRCA1 mutation carriers, 75 BRCA2 mutation carriers, and 308 noncarriers. The physicians and participants were blinded for the results. Serum PSA level≥3.0 ng/ml was used to indicate prostate biopsies. PCA3 was evaluated (1) as an independent indicator for prostate biopsies and (2) as an indicator for prostate biopsies among men with an elevated PSA level. PC detected up to the 2-year screening was used as gold standard as end-of-study biopsies were not performed.ResultsOverall, 23 PCs were diagnosed, 20 of which were in men who had an elevated PSA level in the initial screening round. (1) PCA3, successfully determined in 552 participants, was elevated in 188 (cutoff≥25; 34%) or 134 (cutoff≥35; 24%) participants, including 2 of the 3 PCs missed by PSA. PCA3 would have added 157 (≥25; 28%) or 109 (≥35; 20%) biopsy sessions to screening with PSA only. (2) Elevated PCA3 as a requirement for biopsies in addition to PSA would have saved 37 (cutoff≥25) or 43 (cutoff≥35) of the 68 biopsy sessions, and 7 or 11 PCs would have been missed, respectively, including multiple high-risk PCs. So far, PCA3 performed best among BRCA2 mutation carriers, but the numbers are still small. Because PCA3 was not used to indicate prostate biopsies, its true diagnostic value cannot be calculated.ConclusionsThe results do not provide evidence for PCA3 as a useful additional indicator of prostate biopsies in BRCA mutation carriers, as many participants had an elevated PCA3 in the absence of PC. This must be interpreted with caution because PCA3 was not used to indicate biopsies. Many participants diagnosed with PC had low PCA3, making it invalid as a restrictive marker for prostate biopsies in men with elevated PSA levels. 相似文献
10.
目的:利用近红外漫反射光谱(NIRS)法,结合主成分分析(PCA)和支持向量机(SVM)联用算法,建立6种树脂及其他类中药安息香(Benzoinum),琥珀(Succinum),没药(Myrrha),乳香(Olibanum),松香(Colophonium),天竺黄(Bambusaen Concretio Silicea)的NIR模式识别模型,用于该6味中药的快速鉴别。方法:收集上述6种中药样品,经性状鉴别和理化分析确定正品药材55批,粉碎成均匀粉末,在4 000~12 000 cm~(-1)光谱区,采集各样品粉末的NIR光谱,选取特征谱段9 000~5 400,5 000~4 000 cm~(-1)为建模谱段,分别采用矢量归一化法(vector normalization,VN),一阶导数法(first derivative,FD),二阶导数法(second derivative,SD)3种不同光谱预处理方法进行预处理并分别进行PCA降维。根据主成分空间散点图,优选最佳预处理方法。利用最佳预处理方法处理后光谱的PCA降维数据,建立SVM模式识别模型,SVM模型参数c和g采用网格搜索法结合五折交叉验证进行寻优。对比不同主成分数所建PCA-SVM模型的预测准确率,确定最佳的主成分数,最终建立6种中药NIR快速鉴别模型。结果:在9 000~5 400,5 000~4 000 cm~(-1)建模谱段,确定最佳光谱预处理方法为SD,SD预处理光谱PCA降维后,确定最佳主成分数为3个,累计贡献率达93.57%。经网格搜索法确定最佳SVM建模参数组为c=65 536,g=512。所建PCA-SVM模型对训练集和验证集样品预测正确率均达100%,模型五折交叉验证准确率亦达100%。结论:所建的6种中药NIR光谱PCA-SVM鉴别模型,预测准确率高,模型预测能力强,结合NIRS技术无损、快速的优点,该模型可用于上述6种中药的无损、快速鉴别。 相似文献