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1.
Particle size analysis in the pharmaceutical industry has long been a source of debate regarding how best to define measurement accuracy; the degree to which the result of a measurement or calculation conforms to the true value. Defining a “true” value for the size of a particle can be challenging as the output of its measurement will differ because of variations in measurement approaches, instrumental differences and calculation methods. Consequently, for “real” particles, a universal “true” value does not exist and accuracy is therefore not a definable characteristic. Accordingly, precision is then a measure of the ability to reproducibly achieve a measurement of unknown relevance.This article proposes, in place of accuracy, a means to define the “appropriateness” of a measurement in line with the critical quality attributes (CQA) of the material being characterized. The decision as to whether the measurement is correct should involve a link to the CQA; that is, correlation should be demonstrated, without which the measured particle size cannot be defined as a critical material attribute.Correspondingly, methods should also be able to provide sufficient precision to demonstrate discrimination relating to variation in the CQA. The benefits and challenges of this approach are discussed.  相似文献   
2.
IntroductionPredicting pathological complete response (pCR) for patients receiving neoadjuvant chemotherapy (NAC) is crucial in establishing individualized treatment. Whole-slide images (WSIs) of tumor tissues reflect the histopathologic information of the tumor, which is important for therapeutic response effectiveness. In this study, we aimed to investigate whether predictive information for pCR could be detected from WSIs.Materials and methodsWe retrospectively collected data from four cohorts of 874 patients diagnosed with biopsy-proven breast cancer. A deep learning pathological model (DLPM) was constructed to predict pCR using biopsy WSIs in the primary cohort, and it was then validated in three external cohorts. The DLPM could generate a deep learning pathological score (DLPs) for each patient; stromal tumor-infiltrating lymphocytes (TILs) were selected for comparison with DLPs.ResultsThe WSI feature-based DLPM showed good predictive performance with the highest area under the curve (AUC) of 0.72 among the cohorts. Alternatively, the combination of the DLPM and clinical characteristics offered a better prediction performance (AUC >0.70) in all cohorts. We also evaluated the performance of DLPM in three different breast subtypes with the best prediction for the triple-negative breast cancer (TNBC) subtype (AUC: 0.73). Moreover, DLPM combined with clinical characteristics and stromal TILs achieved the highest AUC in the primary cohort (AUC: 0.82) and validation cohort 1 (AUC: 0.80).ConclusionOur study suggested that WSIs integrated with deep learning could potentially predict pCR to NAC in breast cancer. The predictive performance will be improved by combining clinical characteristics. DLPs from DLPM can provide more information compared to stromal TILs for pCR prediction.  相似文献   
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4.
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   
5.
PurposeAttempts by magnetic resonance (MR) manufacturers to help imaging centres improve patient throughput has led to the development of more automated acquisition. This software is capable of customizing individual scan alignment; potentially improving imaging efficiency and standardizing protocols. However, substantial investments are required to introduce such systems, potentially deterring their widespread application. This study assessed the implementation costs and reduction in examination durations for automated knee MR imaging (MRI) software.Materials and MethodsResearch activities were performed at a community-based academic centre on a 3-Tesla (3-T) system using Siemens' Day Optimizing Throughput (Dot) knee software. Examination acquisition times were extracted from the system before and after software implementation. Fiscal year 2012/13 finances were used to determine the average hourly cost of MRI utilization. Costs associated with automated software implementation were also calculated. Finally, the number of knee scans required to achieve a positive return on investment using the software was established.Results and DiscussionThe mean (standard deviation, sample size) pre- and post-Dot software scan times were 23.20 (4.18, n = 266) and 21.94 (4.51, n = 59) minutes, respectively, for a routine knee scan and 11.88 (1.60, n = 74) and 11.24 (1.51, n = 27) minutes, respectively, for a fast knee scan. The overall weighted average resulted in a 64-second time savings per automated knee examination. This negligible time savings would be extremely difficult to make use of clinically. Dot simplified 29 unique knee protocols to two, improving the consistency of knee examinations. Current Dot software is not compatible with all patients and therefore has limitations that are a concern among MR technologists.ConclusionAdoption of automated knee systems could assist in standardizing protocols; however, the cost of implementation and difficulty in modifying patient scheduling to reflect the minimal time savings would make a financial return unlikely to occur at small- and medium-sized institutions.  相似文献   
6.
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   
7.
Mammalian spermatogenesis is a well-organized process of cell development and differentiation. Meiosis expressed gene 1 (MEIG1) plays an essential role in the regulation of spermiogenesis. To explore potential mechanisms of MEIG1''s action, a yeast two-hybrid screen was conducted, and several potential binding partners were identified; one of them was membrane occupation and recognition nexus repeat containing 3 (MORN3). MORN3 mRNA is only abundant in mouse testis. In the testis, Morn3 mRNA is highly expressed in the spermiogenesis stage. Specific anti-MORN3 polyclonal antibody was generated against N-terminus of the full-length MORN3 protein, and MORN3 expression and localization was examined in vitro and in vivo. In transfected Chinese hamster ovary cells, the antibody specifically crossed-reacted the full-length MORN3 protein, and immunofluorescence staining revealed that MORN3 was localized throughout the cytoplasm. Among multiple mouse tissues, about 25 kDa protein, was identified only in the testis. The protein was highly expressed after day 20 of birth. Immunofluorescence staining on mixed testicular cells isolated from adult wild-type mice demonstrated that MORN3 was expressed in the acrosome in germ cells throughout spermiogenesis. The protein was also present in the manchette of elongating spermatids. The total MORN3 expression and acrosome localization were not changed in the Meig 1-deficient mice. However, its expression in manchette was dramatically reduced in the mutant mice. Our studies suggest that MORN3 is another regulator for spermatogenesis, probably together with MEIG1.  相似文献   
8.
IntroductionThis study aims to construct learning curves related to the realization of standardized postprocessing by radiographer students and to discuss their exploitation and interest.Materials and MethodsThis study was carried out in 21 French students in their 3rd year of training. Two postprocessing protocols in CT (#1 traumatic shoulder; #2 petrous bone) were repeated 15 times by each student. Each achievement was timed to obtain overall learning curves. The realization accuracy was also assessed for each student at each repetition.ResultsThe learning rates for the two protocols are 63% and 56%, respectively. The number of repetitions to reach the reference time for each protocol is 11 and 12, respectively. In both protocols, the standard deviations are significantly reduced and stabilized during repetitions. The mean accuracy progresses more quickly in protocol #1.DiscussionThe measured learning rates reflect a rapid learning process for each protocol. The analysis of the standard deviations shows that students have reached a homogeneous level. The average times and accuracies measured during the last repetitions show that the group has reached a high level of performance. Building learning curves helps students measure their progress and motivates them.ConclusionObtaining learning curves allows trainers/supervisors to qualify the learning difficulty of a task while motivating students/radiographers. The use of learning curves is inline with the competency-based training paradigm.  相似文献   
9.
目的 分析H型高血压患者的舌面诊图像颜色参数特征,探讨H型高血压患者的舌诊、面诊变化规律。方法 运用上海中医药大学自行研制的Smart TCM-1型中医舌面一体仪,采集高血压患者舌面诊图像,提取特征参数,分析健康对照组、H型高血压组与非H型高血压组患者舌面颜色参数特征。结果 ①在舌色各项参数中,H型高血压组舌尖部R值、B值、V值均显著小于健康对照组(P < 0.01);非H型高血压组舌尖部B值显著小于健康对照组(P < 0.01),S值较健康对照组显著增大(P < 0.05);H型高血压组舌尖部R、V值均明显小于非H型高血压组(P < 0.05)。在舌苔各项参数中,H型高血压组舌中H值、V值均明显小于健康对照组(P < 0.05);非H型高血压组舌中V值、舌右V值均显著小于健康对照组(P < 0.01);H型高血压组舌中H值明显小于非H型高血压组(P < 0.05),右侧舌苔S值明显大于非H型高血压组(P < 0.05)。②H型高血压组面色参数鼻G值、下颌G值、口唇R值、口唇V值均明显小于健康对照组(P < 0.05);非H型高血压组前额H值、目眶H值、脸颊H值、鼻H值、下颌H值、整体H值均明显大于健康对照组(P < 0.05);H型高血压组前额H值、目眶G值、目眶H值、脸颊H值、鼻G值、鼻H值、下颌R值、下颌G值、下颌H值、下颌V值、口唇R值、口唇G值、口唇V值、整体R值、整体G值、整体H值、整体V值均明显小于非H型高血压组(P < 0.05)。结论 H型高血压患者苔色偏黄,以舌中部为主,且舌右侧黄苔积聚较明显;H型高血压患者面色为黄中带红,口唇、下颌部更为晦暗。H型高血压患者的舌、面诊特征参数的变化,与高血压病阳亢湿盛病机相符。  相似文献   
10.
Abstract

Purpose: In the context of assistive technology, mobility takes the meaning of “moving safely, gracefully, and comfortably”.The aim of this article is to provide a system which will be a convenient means of navigation for the Visually Impaired people, in the public transport system.

Method: A blind regular commuter who travels by public transport facility finds difficulty in identifying the vehicle that is nearing the stop. Hence, a real-time system that dynamically identifies the nearing vehicle and informs the commuters is necessary. This paper proposes such a system namely the “Vehicle Board Recognition System” (VBRS). Computer Vision techniques such as segmentation, object recognition, text detection and optical character recognition are utilized to build the system, which will detect, analyze, derive and communicate the information to the passengers.

Results: Thanks to the rapid development in technology, there are several navigation systems both hand held and wearable, available to help visually impaired (VI) people move comfortably both indoor and outdoor. Many blind people are not comfortable in using these devices or they are not affordable for them. Thus the proposed system gives them the comfort of navigation.

Conclusion: This system can be installed in the bus stop to assist the Visually Impaired, from externally rather than their hand held or wearable assistive devices.
  • Implications for rehabilitation
  • This proposed system will help the visually impaired to

  • ensure secure navigation

  • be independent of the others

  • develop self confidence.

  • overcome the training, affordability of wearable/ handheld devices.

  相似文献   
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