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Infectious laryngotracheitis is a significant respiratory disease of chickens that causes huge economic losses due to high morbidity and mortality and reduced egg production. A real-time recombinase polymerase amplification (RPA) assay was developed to accurately detect ILTV. The specific probe and primer sets were carefully designed and screened. The real-time RPA assay was carried out at 39 °C for 30 min, and results were obtained within 15 min. The results of the specificity assay showed no fluorescence signals with other avian-related viruses. The sensitivity of the assay was 1 × 102 copies/μL. The low CV value showed that the assay was reproducible. A total of 115 clinical samples were tested using the real-time RPA assay and the real-time PCR assay in parallel; the coincidence rates of the two detection methods were 100%. The results indicated that the real-time RPA assay is a specific, sensitive, rapid, and useful tool for epidemiological studies and clinical diagnosis, especially in the field and in resource-poor areas. 相似文献
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目的分析一腓骨肌萎缩症家系的临床表现及不同基因检测方法的特点。方法收集一CMT家系8名成员临床资料,并应用等位基因特异性PCR-双酶切方法及多重连接依赖的探针扩增技术(MLPA)检测PMP22基因突变情况,同时选择60名性别、年龄无明显差异的健康人做为对照组。结果该家系中患病者以行走不稳、跨阈步态,伴有弓形足为主要临床表现。该家系中5名成员经等位基因特异性PCR-双酶切及MLPA方法均检测出PMP22基因重复序列,其中出现临床症状的有4名(Ⅱ3、Ⅱ9、Ⅱ11、Ⅲ7),未出现临床症状但基因检测结果示PMP22基因重复序列的为携带者有1名(Ⅲ5),家系中余3名成员及对照组60名均未见重复序列。结论基因检测在明确CMT诊断中起重要作用,且MLPA法筛查基因时操作更简便、灵敏度更高、特异性更好。 相似文献
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MR评价垂体腺瘤质地及与其胶原含量的关系 总被引:4,自引:1,他引:3
目的利用MR测量垂体腺瘤不同质地的信号强度,并分析其与肿瘤胶原含量间的关系。方法57例经手术证实的垂体腺瘤标本,术前均行MR检查,根据术中肿瘤硬度分为质地韧组(8例)与质地软组(49例),标本行天狼猩红染色检测其胶原含量。结果纤维化与非纤维化组T1WI瘤体/灰质信号强度比分别为1.31±0.31、1.16±0.26;T1WI瘤体/白质信号强度比分别为1.01±0.25、0.91±0.18,两组间差异无统计学意义(P(0.05);T1+WI瘤体/灰质信号强度比分别为1.83±0.28、1.84±0.51;T1+WI瘤体/白质信号强度比分别为1.56±0.24、1.46±0.37,两组间差异无统计学意义(P(0.05);T2WI瘤体/灰质信号强度比分别为1.15±0.26、1.57±0.46(P(0.05);T2WI瘤体/白质信号强度比分别为1.48±0.39、2.10±0.61,两组间有统计学意义(P(0.01);胶原含量分别为20.03%±7.99%、7.87%±4.82%,两组间有统计学意义(P<0.01);且T2WI瘤体/灰质、T2WI瘤体/白质与胶原含量呈显著负相关(r=-0.531、r=-0.726,P均(0.01)。结论术前MR可以预测垂体腺瘤的质地;其中以T2WI瘤体/白质为预测指标为最佳。胶原含量影响垂体腺瘤质地,MRI上T2WI可以反映其胶原含量的多少。 相似文献
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人端粒酶RNA的cDNA探针制备及其对胃粘膜细胞端粒酶RNA表达的检测 总被引:3,自引:0,他引:3
目的 建立人端粒酶RNA表达的检测方法。方法 制备人端粒酶RNA,(human telomeraseRNA,hTR)的cDNA探针,分别应用RNA斑点杂交与端粒重复序列扩增法(TRAP)分析检测不同胃粘膜的端粒酶RNA的表达与端粒酶活性。结果 人端粒酶RNA的cDNA探针制备成功。18例活检胃癌组织及45例手术胃癌组织RNA斑点杂交检测的阳性率均为l00%,相应TRAP分析的阳性率分别为88.89%、86.67%,低于RNA斑点杂交(P<0.05)。同时RNA斑点杂交结果提示在非癌胃组织中随着肠化程度增高人端粒酶RNA表达也增强。结论 RNA斑点杂交检测人端粒酶RNA,具有高度的敏感性和特异性,弥补了TRAP分析敏感性不足的缺点。 相似文献
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A new implantable bladder volume-monitoring device based on the impedance measurement of the detrusor muscle is described.
The system is completely autonomous and forms a mixed-signal (analogue/digital) feedback loop with a neuro-stimulator to rectify
bladder dysfunctions (incontinence and retention) through neuromuscular stimulation techniques. A programmable instrumentation
amplifier and a signal processing block, to eliminate the artefacts caused by the patient’s movements, have been designed
and tested. The layout for the signal processing block has been realised in 0.8 μm BiCMOS technology. 相似文献
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Alessia Pascale Marialaura Amadio Stefano Govoni Fiorenzo Battaini 《Pharmacological research》2007,55(6):560-569
The brain represents the primary centre for the regulation and control of all our body activities, receiving and interpreting sensory impulses and transmitting information to the periphery. Most importantly, it is also the seat of consciousness, thought, emotion and especially memory, being in fact able to encode, store and recall any information. Memory is really what makes possible so many of our complex cognitive functions, including communication and learning, and surely without memory, life would lose all of its glamour and purpose. Age-associated mental impairment can range in severity from forgetfulness at the border with pathology to dementia, such as in Alzheimer's disease. In recent years, one of the most relevant observations of research on brain aging relates to data indicating that age-related cognitive decline is not only due to neuronal loss, as previously thought; instead, scientists now believe that age-associated functional changes have more to do with the dysfunctions occurring over time. Within this context a prominent role is certainly played by signal transduction cascades which guarantee neuronal cell to elaborate coordinated responses to the multiple signals coming from the outside and to adapt itself to the environmental changes and requests. This review will focus the attention on protein kinase C pathway, with a particular interest on its activation process, and on the role of protein-lipid and protein-protein interactions to selectively localize the cellular responses. Furthermore, information is emerging and will be discussed on the possibility of mRNA stabilization through PKC activation. This review will also approach the issue on how alterations of these molecular cascades may have implications in physiological and pathological brain aging, such as Alzheimer's disease. 相似文献
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W. Ziegler D. von Cramon 《European archives of psychiatry and clinical neuroscience》1986,236(1):44-49
Summary This paper deals with a particular aspect of speech motor control in patients suffering from apraxia of speech. Three experiments are reported concerning the phase relations between individual speech gestures. These include the timing of laryngeal, velar and labial movements relative to lingual gestures.A total of 8 patients and 12 normal controls were examined using speech material which was designed according to appropriate phonetic paradigms. Evaluation was performed on the basis of speech signal parameters referring to the kinematics of inter-articulatory phasing. Deviations of the patient group were found in all three experiments. This suggests that disturbed phase relations of individual speech movements are a general feature of apraxic speech. It is further hypothesized that the described motor symptoms are the origin of a variety of phonemic errors. Support for this view is provided by appropriate examples which refer to the examined paradigms. By this argument, much of the disturbed phonemic structure of apraxic speech may be accounted for by timing deficits. 相似文献