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1.
目的 分析微滴式数字PCR(droplet digital PCR, ddPCR)和实时荧光定量PCR(quantitative real-time PCR,qPCR)的核酸检测结果,比较两种方法检测各类样本的差异性,为改进新型冠状病毒核酸检测方案提供数据支持。 方法 利用ddPCR和qPCR技术对已经确诊的3例新型冠状病毒肺炎患者发病不同时间的全血、尿液、粪便共22份标本进行新型冠状病毒核酸检测。 结果 两种方法对人保守区域基因扩增结果一致:全血标本信号最强,尿液次之,粪便最少;ddPCR在1份全血,1份尿液,5份粪便中检出ORF-1ab和N基因的阳性微滴,qPCR仅在3份粪便中检出上述基因,漏检的3个标本基因拷贝数平均浓度为128 copies/ml;ddPCR在发病<5、5~15、>15 d的各类标本中都有检出,qPCR检出以中晚期为主;重症病例用ddPCR均可测到阳性微滴,qPCR检测的各类标本均为阴性;轻症病例的各类标本中qPCR只有粪便核酸检测阳性,ddPCR检出率高于qPCR。 结论 ddPCR可以有效克服qPCR 灵敏度不足的难题,是对qPCR 的有益补充,尤其是针对病毒载量比较低的血液、尿液和可疑的粪便或肛拭子标本,适用于早期感染的判断及患者治愈后出院诊断。 相似文献
2.
Frédéric Janvier Deborah Delaune Thomas Poyot Eric Valade Audrey Mérens Pierre E. Rollin Vincent Foissaud 《Emerging infectious diseases》2016,22(2):292-294
We evaluated RNA stability of Ebola virus in EDTA blood and urine samples collected from infected patients and stored in West Africa’s environmental conditions. In blood, RNA was stable for at least 18 days when initial cycle threshold values were <30, but in urine, RNA degradation occurred more quickly. 相似文献
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本文建立了聚合酶链反应(PCR)检测人巨细胞病毒(HCMV)方法,探讨了该方法的某些实验条件。用PCR检测24例临床患儿尿标本。证明PCR方法特异、敏感、简便而快速。同科不同属病毒如HSV、EBV等以及人源正常细胞均无假阳性结果:最小检出量可达0.1fg DNA,相当于6个基因拷贝;用水浴箱手控时间即可进行PCR循环,30次循环仅需97min30s;PCR和DNA杂交检测尿标本中HCMV阳性例数分别为20和14例。该结果证明HCMV感染儿童的广泛性和严重性,初步表明儿童肾病综合症与HCMV有关。 相似文献
5.
测定72例健康老年人(60-84岁)和65例健康青中年人(20-50岁)血清和尿β2微球蛋白(β2m),发现前血清β2m浓度比后明显增高(p<0.001);老年组≥70岁尿液β2m浓度也明显增高(p<0.05)。结果表明肾小球滤过率下降随年龄增长而降低,以后再出现肾小管功能减退。本试验较血清尿素氮、肌酐和内生肌酐清除率测定更为敏感。 相似文献
6.
AIMS: Diabetic ketoacidosis (DKA), a life-threatening acute complication of Type 1 diabetes, may be preventable with frequent monitoring of glycaemia and ketosis along with timely supplemental insulin. This prospective, two-centre study assessed sick day management using blood 3-hydroxybutyrate (3-OHB) monitoring compared with traditional urine ketone testing, aimed at averting emergency assessment and hospitalization. METHODS: One hundred and twenty-three children, adolescents and young adults, aged 3-22 years, and their families received sick day education. Participants were randomized to receive either a blood glucose monitor that also measures blood 3-OHB (blood ketone group, n = 62) or a monitor plus urine ketone strips (urine ketone group, n = 61). All were encouraged to check glucose levels > or = 3 times daily and to check ketones during acute illness or stress, when glucose levels were consistently elevated (> or = 13.9 mmol/l on two consecutive readings), or when symptoms of DKA were present. Frequency of sick days, hyperglycaemia, ketosis, and hospitalization/emergency assessment were ascertained prospectively for 6 months. RESULTS: There were 578 sick days during 21,548 days of follow-up. Participants in the blood ketone group checked ketones significantly more during sick days (276 of 304 episodes, 90.8%) than participants in the urine ketone group (168 of 274 episodes, 61.3%) (P < 0.001). The incidence of hospitalization/emergency assessment was significantly lower in the blood ketone group (38/100 patient-years) compared with the urine ketone group (75/100 patient-years) (P = 0.05). CONCLUSIONS: Blood ketone monitoring during sick days appears acceptable to and preferred by young people with Type 1 diabetes. Routine implementation of blood 3-OHB monitoring for the management of sick days and impending DKA can potentially reduce hospitalization/emergency assessment compared with urine ketone testing and offers potential cost savings. 相似文献
7.
Two topical corticosteroids, budesonide (BUD) and beclomethasone dipropionate (BDP), both administered as suspensions in water, were investigated in healthy volunteers regarding influence on cortisol in plasma and urine (U-cortisol) after nasal application. In the first study, single doses of 200, 400, and 800 μg of BDP and BUD were given at 10:00 pm. In the second study, 100, 200, and 400 μg were given mornings and evenings for 4 days. In the single-dose study, none of the drugs or doses showed any significant influence on cortisol in plasma. However, U-cortisol decreased significantly after BUD 400 and 800 μg. In the multidose study, U-cortisol values were significantly reduced after all doses of BUD and the highest dose of BDP. The compounds tested showed different ability to cause measurable systemic effects after nasal application. The clinical implication is that the prescriber, when choosing a compound, should take the application site into consideration and should also be encouraged to find the lowest effective dose. 相似文献
8.
尿样中加入Triton X-100后,在尿蛋白和其它物质存在下可用可见分光光度法直接而快速地测定尿锌.该法比目前其它方法更简便,尤其适合于临床快速分析.经40例正常人尿锌含量分析,结果((?)±s)为0.789±0.256μg/ml,与文献值基本一致. 相似文献
9.
Takashi Hineno M.D. Mutsuhiko Mizobuchi M.D. Oh-ichi Nishimatsu M.D. Jun Horiguchi M.D. Yasuo Kakimoto M.D. 《Psychiatry and clinical neurosciences》1994,48(3):583-587
Abstract: Studies on the circadian rhythm of urine excretion in healthy men have demonstrated that the maximal urine flow occurs in the early afternoon and the minimal around midnight. In this study, an abnormality in the variation of urine volume was found in parkinsonian patients. Urine samples were collected during daytime (9:00–21:00) and nighttime (21:00–9:00). Fifteen healthy control subjects were examined and found to excrete 60% during the daytime and 40% during the nighttime of the total urine volume. Sixteen parkinsonian patients excreted 43% during the daytime and 57% during the nighttime. In contrast to the control subjects, the parkinsonian patients excreted a smaller volume of their urine during the daytime than during the nighttime. This finding might be related to the degeneration of dopaminergic and/or nondopaminergic neurons in the brain which control urinary excretion. 相似文献
10.