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1.
《Vaccine》2022,40(6):924-933
The European Clinical Trial Regulation No 536/2014 is the first mandate for a non-technical, publicly disclosed, plain language summary (PLS) of clinical trial results. This easy-to-understand summary has the potential to inform the public about clinical trial results and thereby improve health literacy in vaccines.To investigate the utility of the PLS, we undertook 2 online surveys (July/October 2020) in the United Kingdom, the United States and India. Participants were selected by quota sampling to ensure representation of gender, age and parental status. Those lacking interest in vaccine clinical research were excluded. In survey 1, participants were questioned about their interest in and expectations of vaccine trial results. In survey 2, the perceptions of participants to a range of written communication styles used in publicly available PLSs were evaluated.A total of 66 (13%) and 122 (29%) individuals were excluded solely due to lack of interest in vaccine clinical research in surveys 1 and 2, respectively; 450 respondents (150/country) completed survey 1 and 300 (100/country) completed survey 2. In survey 1, there was a correlation (p < 0.01) between claimed knowledge of and trust in vaccines. Healthcare professionals were the most trusted source for vaccine information, while vaccine companies were ranked relatively low. In survey 2, infographic PLS formats were considered easiest to understand, most engaging and the strongest communicators. Emphasizing the main points of the infographics in the text did not improve comprehension or recall. Most respondents (86%) indicated that they would like to see this type of communication in the future.Overall, this research suggests that the PLS, by optimizing content and format, has a potential to increase health literacy, and thereby, as part of a wider integrated communication strategy, build vaccine knowledge and confidence.  相似文献   
2.

Background

Construct validity for the pediatric laparoscopic surgery (PLS) simulator has been established through a scoring system based on time and precision. We describe the development and initial validation of motion analysis to teach and assess skills related to pediatric minimal access surgery (MAS).

Methods

Participants were asked to perform a standardized intracorporeal suturing task. They were classified as novices, intermediates, and experts. Motion in the four degrees of freedom available during traditional MAS (PITCH, YAW, ROLL and SURGE) was assessed using range, velocity, and acceleration.

Results

Analysis of motion allowed discrimination between the 75 participants according to level of expertise. The most discriminating motion parameter was the acceleration in performing the ROLL (pronation/supination) with values of 30 ± 27 for novices, 15 ± 5 for intermediates, and 3.7 ± 3 for experts (p < 0.001).

Conclusions

Tracking and analyzing the motion of instruments within the PLS simulator allow discrimination between novices, intermediates, and experts, thus establishing construct validity. Further development may establish motion analysis as a useful “real time” modality to teach and assess MAS skills.  相似文献   
3.
Background and AimCeramides are poorly characterized in human adipose tissue. The aim of this study was to investigate concentrations of different ceramide species in human subcutaneous and visceral adipose tissue depots and to determine associations between ceramides and global gene expression profiles.Methods and ResultsConcentrations of six ceramide species were determined in plasma and in subcutaneous and mediastinal adipose tissue from 10 overweight subjects (BMI 29.4 ± 4.9 kg/m2). In the adipose tissue biopsies gene expression arrays were performed and relationships between ceramides and gene expression analyzed. Immunostaining of the two adipose tissue depots was performed in an independent group of 10 patients. Mediastinal adipose tissue contained significantly higher concentrations (p < 0.05) of all six ceramide species than the subcutaneous depot. Of the six ceramides in plasma, concentrations of only two (Cer d18:1/18:0 and Cer d18:1/22:0) correlated significantly (p < 0.05) with the corresponding species in mediastinal adipose tissue, but there were no significant correlations between ceramides in plasma and subcutaneous adipose tissue. Multivariate analysis identified significant correlations between the total ceramide concentration and global gene expression within mediastinal, but not subcutaneous adipose tissue, according to cross-validation. Gene ontology analysis of genes related to ceramides in the mediastinal depot revealed that genes positively correlated with ceramides were associated mainly with immune and inflammatory categories, while genes negatively correlated with ceramides were associated mainly with lipid and carbohydrate metabolism.ConclusionsCeramides in human mediastinal adipose tissue may be involved in inflammation and lipid and carbohydrate metabolism.  相似文献   
4.

Background

Auditory neural myelination (ANM) as evaluated by auditory brainstem evoked response (ABR) during the neonatal period has been used as a surrogate outcome for long-term neurodevelopment. The validity of ANM as a surrogate outcome for long-term neurodevelopment has not been well studied.

Aim

Evaluate the association of ABR I–V interpeak latency (IPL), an index of ANM, at 35 week postmenstrual age (PMA) with language outcome at 3 years of age.

Design

Prospective study.

Subjects

24–33 week gestational age (GA) infants were eligible if they did not meet exclusion criteria: craniofacial malformation, chromosomal disorders, deafness, auditory dys-synchrony, TORCH infection, or non-English speaking parents. Infants with malignancy, head injury, encephalopathy, meningitis, blindness, or who died or relocated were also excluded.

Outcome measures

ABRs were performed at 35 week PMA using 80 dB nHL and I–V IPL (ms) measured. Auditory Comprehension (AC) and Expressive Communication (EC) were evaluated by a speech-language pathologist at 3 years of age using Preschool Language Scale.

Results

Eighty infants were studied. The mean GA and birth weight of infants were 29.2 weeks and 1336 g, respectively. There was association of worse ear I–V IPL and better ear I–V IPL with AC (Coefficient − 5.4, 95% CI: − 9.8 to − 0.9 and Coefficient − 5.5, 95% CI: − 10  to−0.9, respectively) and EC (Coefficient − 5.6, 95% CI: − 9.5  to−1.8 and Coefficient − 6.7, 95% CI: − 10.6  to−2.7, respectively) after controlling for confounders.

Conclusion

The neonatal I–V IPL is a predictor of language development at 3 years of age in preterms.  相似文献   
5.
Objective: To propose a better statistical method of predicting postsurgery soft tissue response in Class II patients.Materials and Methods:The subjects comprise 80 patients who had undergone surgical correction of severe Class II malocclusions. Using 228 predictor and 64 soft tissue response variables, we applied two multivariate methods of forming prediction equations, the conventional ordinary least squares (OLS) method and the partial least squares (PLS) method. After fitting the equation, the bias and a mean absolute prediction error were calculated. To evaluate the predictive performance of the prediction equations, a leave-one-out cross-validation method was used.Results:The multivariate PLS method provided a significantly more accurate prediction than the conventional OLS method.Conclusion:The multivariate PLS method was more satisfactory than the OLS method in accurately predicting the soft tissue profile change after surgical correction of severe Class II malocclusions.  相似文献   
6.
近红外光谱法测定复方丹参滴丸中的3种有效成分   总被引:30,自引:1,他引:30       下载免费PDF全文
 目的面向中药制药过程,提出一种用近红外(NIR)漫反射光谱快速测定复方丹参滴丸有效成分的新方法。方法采用HPLC为对照分析法测定滴丸中3种酚酸类有效成分:丹参素(danshensu,Da)、原儿茶醛(protocatechuic aldehyde,Pra)和丹酚酸B(salvianolic acid B,Sal B)含量。运用偏最小二乘(PLS)法建立NIR光谱与3成分HPLC分析值之间的多元校正模型,对未知样本进行含量预测。结果校正模型相关系数分别为0.994 2,0.996 5和0.971 4,验证集相对预测误差均方根(RSEP)分别为5.916 1%,9.291 7%和12.423 2%。结论本法操作简便、快速无损,可用于中药复方制剂有效成分快速检测。  相似文献   
7.
甲硝唑的非破坏分析   总被引:2,自引:1,他引:1  
偏最小二乘(PLS)法同近红外漫反射光谱法结合,非破坏分析了粉末药品甲硝唑。讨论了波长对PLS定量预测能力的影响。校正样品和预测样品预测结果的相对标准误差分别为0.0866%和0.1557%。结果满意  相似文献   
8.
The aim of this study was to utilise a new approach where digital image information is used in the characterisation of particle size distributions of a large set of pharmaceutical powders. A novel optical set-up was employed to create images and calculate a stereometric parameter from the digital images of powder surfaces. Analysis was made of 40 granule batches with varying particle sizes and compositions prepared with fluidised bed granulation. The extracted digital image information was then connected to particle size using multivariate modelling. The modelled particle size distributions were compared to particle size determinations with sieve analysis and laser diffraction. The results revealed that the created models corresponded well with the particle size distributions measured with sieve analysis and laser diffraction. This study shows that digital images taken from powder surfaces contain all necessary data that is needed for particle size distribution analysis. To obtain this information from images careful consideration has to be given on the imaging conditions. In conclusion, the results of this study suggest that the new approach is a powerful means of analysis in particle size determination. The method is fast, the sample size needed is very small and the technique enables non-destructive analysis of samples. The method is suitable in the particle size range of approximately 20–1500 μm. However, further investigations with a broad range of powders have to be made to obtain information of the possibilities and limitations of the introduced method in powder characterisation.  相似文献   
9.
本文研究了复方阿斯匹林片中阿斯匹林、非那西丁和咖啡因含量同时测定的紫外分光光度法的最佳实验条件,并简述偏最小二乘法(PLS)在多组分同时测定中的基本原理和应用。三组分模拟试样回收率平均值的置信区间分别为100.1±0.23%,100.0±0.25%和100.1±0.33%(置信度95%)。PLS法是一种理想的多组分测定方法,计算速度较快,结果更准确可靠,尤其适用于成批试样的分析,为微机控制的紫外可见分光光度计提供了一种新方法。  相似文献   
10.
Different motor neuron disorders (MND s ) are mainly defined by the clinical presentation based on the predominance of upper or lower motor neuron impairment and the course of the disease. Magnetic resonance imaging (MRI) mostly serves as a tool to exclude other pathologies, but novel approaches such as diffusion tensor imaging (DTI) have begun to add information on the underlying pathophysiological processes of these disorders in vivo. The present study was designed to investigate three different rare MNDs, i.e., primary lateral sclerosis (PLS, N = 25), hereditary spastic paraparesis (HSP, N = 24), and X‐linked spinobulbar muscular atrophy (X‐SBMA, N = 20), by use of whole‐brain‐based DTI analysis in comparison with matched controls. This analysis of white matter (WM) impairment revealed widespread and characteristic patterns of alterations within the motor system with a predominant deterioration of the corticospinal tract (CST) in HSP and PLS patients according to the clinical presentation and also in patients with X‐SBMA to a lesser degree, but also WM changes in projection s to the limbic system and within distinct areas of the corpus callosum (CC), the latter both for HSP and PLS. In summary, DTI was able to define a characteristic WM pathoanatomy in motor and extra‐motor brain areas, such as the CC and the limbic projectional system, for different MNDs via whole brain‐based FA assessment and quantitative fiber tracking. Future advanced MRI‐based investigations might help to provide a fingerprint‐identification of MNDs. Hum Brain Mapp, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
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