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991.
目的探讨微粒子化学发光检测技术(MEIA),酶联免疫吸附试验(ELISA)和胶体金免疫层析试验(GICA)检测乙型肝炎病毒表面抗原(HBs Ag)的结果符合率。方法用MEIA、ELISA和GICA三种方法对200份标本进行乙型肝炎病毒表面抗原检测,比较三种方法的阳性率、敏感度和特异度。结果 ELISA法阳性率为43.5%,阴性率为56.5%;GICA法阳性率为41.0%,阴性率为59.0%;MEIA法阳性率为45.5%,阴性率为54.5%。ELISA与MEIA符合度较高,阳性率较高,GICA与MEIA符合度差,阳性率最低。三种方法中以MEIA法的敏感度和特异度最高,其次为ELISA法,GICA法最低。结论 GICA灵敏度较低,只能作为初筛;ELISA较MEIA灵敏度略低,遇到检测样本吸光度值(OD值)在对照样本临界值(cut off值)附近时,需要复检。  相似文献   
992.
目的探索在不同的情境利害关系下,亲疏关系对大学生良心行为的影响。方法使用内隐联结测验(IAT)测量100名中国大学生的良心行为。在内隐联结测验(IAT)中,通过内隐测量方法讨论情境利害关系大小和亲疏关系大小两个因素对大学生良心行为的影响效果,用利害关系不同的情境故事材料作为实验启动条件,考察在不同情境下,个体对亲疏概念与积极属性/消极属性词的联系是否存在差异;随着亲缘关系的增加,情境因素是否会影响良心行为反应产生的可能性。结果相对于非亲属概念与积极属性,亲属概念与积极属性的联系更强,即表现出了亲疏关系的良心内隐效应,而且这种效应在利害关系小的情境启动下表现更突出(t1=387.4642,t2=262.9428),两种情境下的良心内隐效应值差异极其显著(t=5.594,P0.001),且效应值不存在性别差异(t=0.141,P=0.888)和专业差异(t=1.07,P=0.287)。结论情境利害和亲疏关系对大学生良心行为有影响。  相似文献   
993.
BackgroundBariatric surgery has been shown to improve many obesity related co-morbidities, including gestational diabetes mellitus (GDM). Recently, new diagnostic criteria for GDM following the International Association of Diabetes and Pregnancy Study Group recommendations were implemented. The objective of this study was to compare the use of 2 different GDM criteria in diagnostic and pregnancy outcome after Roux-en-Y gastric bypass (RYGB).MethodsPregnant women who had previously undergone RYGB (n = 30) were screened for GDM with Carpenter and Coustan (C&C) criteria (n = 18) or the new diagnostic criteria (n = 12).ResultsNone of the patients screened using C&C criteria where diagnosed with GDM, while 50% of the patients screened with the new criteria had GDM. Among women that underwent oral glucose tolerance tests (OGTT) (n = 19) as required for the new diagnostic criteria, 57.9% developed reactive hypoglycemia. All women diagnosed with GDM had excellent metabolic control during pregnancy and comparing the outcome of these pregnancies and those of women without GDM, there were no significant differences regarding the age at time of surgery or at pregnancy, body mass index before surgery and pregnancy, parity, previous history of GDM, time from surgery to conception, weight lost until pregnancy, weight gain during pregnancy, gestational age at delivery, and birth weight adjusted for gestational age.ConclusionNew GDM diagnostic criteria in post-RYGB pregnant women increased the prevalence of GDM diagnostic without changing pregnancy outcomes. In addition, OGTTs were associated with a high rate of reactive hypoglycemia. These data suggest that alternative GDM diagnostic criteria are needed for these postbariatric patients.  相似文献   
994.
ObjectiveValidation of linking coefficients to transform Pediatric Spinal Cord Injury Activity Measure (PEDI-SCI/AM) scores to adult Spinal Cord Injury-Functional Index (SCI-FI) scores.DesignThis cross-sectional study administered PEDI-SCI/AM and SCI-FI computerized adaptive tests (CATs) and short forms (SFs) to children with SCI and parents or caregivers.SettingHospitals, university, and rehabilitation institute.ParticipantsAbout 107 children with SCI and 96 parent or caregivers.InterventionsNot applicable.Main Outcome MeasuresLinking coefficients estimated SCI-FI (est-SCI-FI) scores from PEDI-SCI/AM scores for matched domains. Correlations between est-SCI-FI and actual SCI-FI scores were calculated. If correlations exceeded the criterion linking (0.866), the following analyses to compare est-SCI-FI and actual SCI-FI scores were conducted: paired t tests, intraclass correlation coefficients (ICCs 3, 1), percent of cases with absolute score differences at different thresholds.ResultsTwo matched domains, PEDI-SCI/AM Daily Routine/SCI-FI Self-Care and PEDI-SCI/AM General Mobility/SCI-FI Basic Mobility, met the linking criterion for both respondent-types (parent and child) and administration modes (CAT and SF). PEDI-SCI/AM Daily Routine and SCI-FI Fine Motor Function did not meet linking criterion for respondent type or mode. The linking criterion was met for wheelchair domains (child SF and CAT) and ambulation domains (child SF only). Significant differences between est-SCI-FI and actual SCI-FI scores were noted for all matched domains except Daily Routine/Self-Care (child SF only; parent SF and CAT). ICC values showed excellent agreement (range=0.75-0.89). Absolute differences between est-SCI-FI and actual SCI-FI scores were less than 1 standard deviation (except wheelchair CAT child).ConclusionsLinking coefficients applied to PEDI-SCI/AM scores can provide valid SCI-FI estimates that vary by domain, mode, and respondent type.  相似文献   
995.
The appearance of a surface can be controlled by creating periodic microstructures designed to diffract light and produce structural colors. Nevertheless, since structural coloration is based on diffraction, the produced colors have a strong dependence on the viewing angle and absence of coloration takes place while tilting the samples. In this work direct laser interference patterning is used to firstly provide transparent polymer sheets a structural coloration with a high‐range observation angle, and secondly to demonstrate the combination of structural colors, producing a white coloring effect. The employed approaches are based on the fabrication of micro‐gratings with multiple periods in the same structured area and on the engineering of the diffraction orders of the diffraction spectrum. The patterned surfaces are characterized by confocal microscopy and angular spectrometry in reflection mode. The morphological characterization shows homogeneous surface patterns, while the spectral results demonstrate that combining four spatial periods on a single patterned surface, a white appearance is obtained over an angular observation range higher than 30°. The experimental results are supported by theoretical predictions by means of generalized formulas based on the diffraction of light.  相似文献   
996.
997.
The wave analysis of swallowing sounds has been receiving attention because the recording process is easy and non‐invasive. However, up until now, an expert has been needed to visually examine the entire recorded wave to distinguish swallowing from other sounds. The purpose of this study was to establish a methodology to automatically distinguish the sound of swallowing from sound data recorded during a meal in the presence of everyday ambient sound. Seven healthy participants (mean age: 26·7 ± 1·3 years) participated in this study. A laryngeal microphone and a condenser microphone attached to the nostril were used for simultaneous recording. Recoding took place while participants were taking a meal and talking with a conversational partner. Participants were instructed to step on a foot pedal trigger switch when they swallowed, representing self‐enumeration of swallowing, and also to achieve six additional noise‐making tasks during the meal in a randomised manner. The automated analysis system correctly detected 342 out of the 352 self‐enumerated swallowing events (sensitivity: 97·2%) and 479 out of the 503 semblable wave periods of swallowing (specificity: 95·2%). In this study, the automated detection system for swallowing sounds using a nostril microphone was able to detect the swallowing event with high sensitivity and specificity even under the conditions of daily life, thus showing potential utility in the diagnosis or screening of dysphagic patients in future studies.  相似文献   
998.
In this study, we aimed to explore the effect of inducible nitric oxide synthase (iNOS) on vascular endothelial growth factor (VEGF) expression in salivary gland adenoid cystic carcinoma (SACC). Using RNAi, we transfected chemically synthesised iNOS siRNA into ACC‐M cells (a highly metastatic adenoid cystic carcinoma cell line) and detected the change in the gene and protein expression levels of iNOS and VEGF by qRT‐PCR and Western blotting. A transwell invasiveness assay was used to examine the changes in invasive ability of ACC‐M cells. Cell growth was determined using a CCK‐8 assay. Apoptosis and cell‐cycle phases were detected by flow cytometry. We found that silencing iNOS down‐regulated the expression of VEGF and then inhibited cell growth and invasiveness of SACC cells, while it increased apoptosis. Therefore, we concluded that iNOS can regulate VEGF expression and iNOS may be a therapeutic target.  相似文献   
999.
ObjectivesEfficient interruption of Ebola virus disease (EVD) transmission chains critically depends on reliable and fast laboratory diagnosis. We evaluated the performance of the EBOLA Virus Antigen Detection K-SeT (EBOLA Ag K-SeT), a new rapid diagnostic antigen test in field settings.MethodsThe study was conducted in a field laboratory located in Freetown (Sierra Leone) by the Italian National Institute for Infectious Diseases ‘L. Spallanzani’ and the EMERGENCY Onlus NGO. The EBOLA Ag K-SeT was tested on 210 residual plasma samples (EVD prevalence 50%) from patients hospitalized at the EMERGENCY Ebola treatment center in Goderich (Freetown), comparing the results with quantitative real-time PCR.ResultsOverall, the sensitivity of EBOLA Ag K-SeT was 88.6% (95% confidence interval (CI), 82.5–94.7), and the corresponding specificity was 98.1% (95% CI, 95.5–100.7). The positive and negative predictive values were 97.9% (95% CI, 95.0–100.8) and 89.6% (95% CI, 84–95.2), respectively. The sensitivity strongly increased up to 98.7% (95% CI, 96.1–101.2) for those samples with high virus load (≥6.2 log RNA copies/mL).ConclusionsOur results suggest that EBOLA Ag K-SeT could represent a new effective diagnostic tool for EVD, meeting a need for resource-poor settings and rapid diagnosis for individuals with suspected EVD.  相似文献   
1000.
This review describes the landscape of novel modalities such as cell and gene therapies, viruses, other novel biologics, oligomers, and emerging technologies, including modern analytics. We summarize the regulatory history and recent landmark developments in some major markets and examine specific chemistry, manufacturing, and controls (CMC) challenges, including suggestions for exploration of potential science-based approaches in support of regulatory strategy development from an industry perspective. In addition, we evaluate the economic factors contributing to patient access to innovation and discuss the impact of regulation. There is a desperate need for a consistent form of regulation where global approaches to regulatory strategies can be harmonized, and specific CMC challenges can be dealt with using the appropriate science and risk-based tools. Although these tools are well described in current guidance documents, the specifics of applicability to complex novel modalities can still result in differing regulatory advice and outcomes. The future goals for efficiently regulating innovative modalities and technologies could be aided by more regulatory harmonization, regulatory education, and industry cooperation through consortia, enabling industry to supply key information to regulators in a transparent yet well-defined manner, and utilizing mutually understood risk-benefit analyses to produce drugs with appropriate safety, efficacy, and quality characteristics.  相似文献   
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