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排序方式: 共有1095条查询结果,搜索用时 31 毫秒
1.
《The Brazilian journal of infectious diseases》2021,25(2):101543
In the pandemic, rapid and accurate detection of SARS-CoV-2 is crucial in controlling the outbreak. Recent studies have shown a high detection rate using saliva/oral fluids as specimens for laboratory detection of the virus. We intended to evaluate the test performance of the Xpert Xpress SARS-CoV-2 cartridge assay in comparison to a conventional qRT-PCR testing, using saliva as biological specimen. Forty saliva samples from symptomatic participants were collected. Conventional qRT-PCR was performed for amplification of E and RdRp genes and the Xpert Xpress SARS-CoV-2 assay amplified E and N2 genes. In the conventional assay, the median cycle threshold value of the E gene was 34.9, and of the RdRp gene was 38.3. In the Xpert Xpress assay, the median cycle threshold value of the E gene was 29.7, and of the N2 gene was 31.6. These results can allow a broaden use of molecular tests for management of COVID-19 pandemic, especially in resources-limited settings. 相似文献
2.
Many studies have reported age-associated DNA methylation changes and age-predictive models in various tissues and body fluids. Although age-associated DNA methylation changes can be tissue-specific, a multi-tissue age predictor that is applicable to various tissues and body fluids with considerable prediction accuracy might be valuable. In this study, DNA methylation at 5 CpG sites from the ELOVL2, FHL2, KLF14, C1orf132/MIR29B2C, and TRIM59 genes were investigated in 448 samples from blood, saliva, and buccal swabs. A multiplex methylation SNaPshot assay was developed to measure DNA methylation simultaneously at the 5 CpG sites. Among the 5 CpG sites, 3 CpG sites in the ELOVL2, KLF14 and TRIM59 genes demonstrated strong correlation between DNA methylation and age in all 3 sample types. Age prediction models built separately for each sample type using the DNA methylation values at the 5 CpG sites showed high prediction accuracy with a Mean Absolute Deviation from the chronological age (MAD) of 3.478 years in blood, 3.552 years in saliva and 4.293 years in buccal swab samples. A tissue-combined model constructed with 300 training samples including 100 samples from each blood, saliva and buccal swab samples demonstrated a very strong correlation between predicted and chronological ages (r = 0.937) and a high prediction accuracy with a MAD of 3.844 years in the 148 independent test set samples of 50 blood, 50 saliva and 48 buccal swab samples. Although more validation might be needed, the tissue-combined model’s prediction accuracies in each sample type were very much similar to those obtained from each tissue-specific model. The multiplex methylation SNaPshot assay and the age prediction models in our study would be useful in forensic analysis, which frequently involves DNA from blood, saliva, and buccal swab samples. 相似文献
3.
咖啡因主要经肝细胞色素P450IA2代谢,测定其药代动国学参数可反映该P450亚型的活性。本研究显示咖啡因清除相为一级动力学;唾液和血浆的药代动力学参数有良好的相关性;含体重因素的清除率的变异系数比半减期小;用一次采样测定其清除率以8h时点为宜。 相似文献
4.
Pharmacokinetics of orally administered hexobarbital in plasma and saliva of healthy subjects 总被引:1,自引:0,他引:1
M van der Graaff N P Vermeulen P Heij J K Boeijinga D D Breimer 《Biopharmaceutics & drug disposition》1986,7(3):265-272
Hexobarbital (HB) concentrations were determined in plasma and saliva of 8 healthy subjects, following oral administration of 500 mg HB-Na. Mean plasma half-lives were 3.2 +/- 0.1 h, and salivary half-lives 3.3 +/- 0.2 h. Mean plasma clearance was 22.9 +/- 2.3 1 h-1. There was a linear relationship between HB concentrations in saliva and plasma (r = 0.92). Mean salivary levels were 34 per cent of plasma levels. Salivary pH was constant throughout the experiment, 7.06 +/- 0.09. There was an inconsistent tendency of the saliva over plasma ratios to increase as a function of time. The percentage of protein binding calculated from saliva over plasma ratios was in reasonable agreement with in vitro data of equilibrium dialysis, 64.1 +/- 2.6 per cent and 65.9 +/- 0.8 per cent, respectively. The experiment was repeated in 4 subjects, and considerable intraindividual differences were shown to exist in saliva over plasma ratio, half-lives, and protein binding. It was concluded that HB elimination half-lives can relatively accurately be determined from salivary concentrations. Oral plasma clearance can only be estimated if the individual saliva over plasma ratios are known; this would require the taking of at least one blood sample during the experiment. When employing HB as a model substrate for drug metabolizing enzyme activity in vivo, the determination of its pharmacokinetic parameters, particularly oral plasma clearance as a reflection of cytochrome P-450 activity, cannot be achieved by taking saliva samples only. 相似文献
5.
lgY牙膏对口腔变形链球菌的抑制作用 总被引:2,自引:0,他引:2
目的研究含生物活性物IgY牙膏对口腔变形链球菌的抑制作用.方法将140位受试者随机分成实验组和对照组.每位受试者经过2个月洗脱期后,分别使用实验牙膏和空白对照牙膏.采用Dentocult SM方法分别测出基线值和使用1d、3d、7d、1个月后以及停止使用牙膏后2周的口腔变形链球菌水平.结果①实验组受试者口腔中变形链球菌水平的下降发生在使用实验牙膏刷牙后第1天,而对照组则发生在刷牙后的第3天.②随着刷牙时间延长,2组受试者口腔中变形链球菌水平逐步下降.③实验组停止使用实验牙膏刷牙后2周,仍有抑制变形链球菌的作用.结论与对照组相比,实验组牙膏有增强抑制口腔变形链球菌的作用. 相似文献
6.
本研究对123例月经周期正常妇女的N-乙酰-β-D氨基葡萄糖苷酶(简称NAG酶)进行162个周期的观察,使用对硝基苯—N-乙酰-β-D氨基葡萄糖苷作底物与唾液中的NAG酶进行酶促反应。在一定条件下NAG酶作用于底物产生N-乙酰-β-D氨基葡萄糖和对硝基酚,再加一定量的碱溶液终止其酶反应,使对硝基酚呈黄色,然后进行比色,并以尿样LH(单克隆抗体酶免疫法)作为对照观察周期性变化。结果表明:在排卵前和排卵期NAG酶活性上升,通常在下次月经前13~17天之间。准确率90%与尿样LH对照符合率95%。 相似文献
7.
K.K.W. To C.C.Y. Yip C.Y.W. Lai C.K.H. Wong D.T.Y. Ho P.K.P. Pang A.C.K. Ng K.-H. Leung R.W.S. Poon K.-H. Chan V.C.C. Cheng I.F.N. Hung K.-Y. Yuen 《Clinical microbiology and infection》2019,25(3):372-378
Objectives
Automated point-of-care molecular assays have greatly shortened the turnaround time of respiratory virus testing. One of the major bottlenecks now lies at the specimen collection step, especially in a busy clinical setting. Saliva is a convenient specimen type that can be provided easily by adult patients. This study assessed the diagnostic validity, specimen collection time and cost associated with the use of saliva.Methods
This was a prospective diagnostic validity study comparing the detection rate of respiratory viruses between saliva and nasopharyngeal aspirate (NPA) among adult hospitalized patients using Xpert® Xpress Flu/RSV. The cost and time associated with the collection of saliva and nasopharyngeal specimens were also estimated.Results
Between July and October 2017, 214 patients were recruited. The overall agreement between saliva and NPA was 93.3% (196/210, κ 0.851, 95% CI 0.776–0.926). There was no significant difference in the detection rate of respiratory viruses between saliva and NPA (32.9% (69/210) versus 35.7% (75/210); p 0.146). The overall sensitivity and specificity were 90.8% (81.9%–96.2%) and 100% (97.3%–100%), respectively, for saliva, and were 96.1% (88.9%–99.2%) and 98.5% (94.7%–99.8%), respectively, for NPA. The time and cost associated with the collection of saliva were 2.26-fold and 2.59-fold lower, respectively, than those of NPA.Conclusions
Saliva specimens have high sensitivity and specificity in the detection of respiratory viruses by an automated multiplex Clinical Laboratory Improvement Amendments-waived point-of-care molecular assay when compared with those of NPA. The use of saliva also reduces the time and cost associated with specimen collection. 相似文献8.
Nelson L. Rhodus Bin Cheng Sandra Myers Walter Bowles Vu Ho Frank Ondrey 《Clinical immunology (Orlando, Fla.)》2005,114(3):278
To explore the feasibility of detection of the level of NF-κB-dependent cytokines in oral fluids from patient with oral lichen planus (OLP) for clinical application, 13 OLP subjects were enrolled in the study as were 13 age–sex-matched controls. In each subject, the whole unstimulated saliva (WUS), mixture of saliva and isotonic saline oral rinse (Saliva-NaCl), and lesion tissue transudates (TT) were collected by standard techniques. The level of cytokines, TNF-alpha, IL-1-alpha, IL-6, and IL-8 in three types of oral fluids was determined by ELISA. In the three types of oral fluids, a significantly higher level of these cytokines was detected in OLP patients than in normal controls. These results indicate that NF-κB-dependent inflammatory cytokines may be detected at increased levels in certain oral fluids which may have diagnostic and prognostic potential for monitoring disease activity and making therapeutic decisions in patients with OLP. 相似文献
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