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Chikungunya and dengue, two arboviral infections are common in South-East Asia and their early clinical manifestations are very similar hence it is important to discriminate between them as early as possible for better clinical management. The aim of this study was to design a rapid, sensitive and specific method for the differential diagnosis of these two viruses simultaneously. A rapid one-tube duplex RT-PCR assay was developed that requires 110 min including RNA extraction, RT-PCR and agarose gel electrophoresis by using a novel Taq polymerase with high processivity. This one-tube duplex RT-PCR system with primers designed from the conserved regions of the genome allowed discrimination between the two viral groups. Bioinformatics analysis of the DNA sequences from PCR amplified products confirmed that this method was very specific and accurate. The time required for this duplex RT-PCR was comparable to the standard IgM capture ELISA method. This novel approach would help to diagnose specifically and accurately these two closely related arboviruses and enable early detection from blood. This method could be applied in resource limited settings, for surveillance in endemic regions or for routine epidemiological screening.  相似文献   
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The first step towards detection of valvular heart diseases from heart sound signal (phonocardiogram) is segmentation. A segmentation algorithm provides the location of the first and second heart sounds which in turn helps to locate and analyse the murmur. Established phonocardiogram based segmentation methods use an electrocardiographic (ECG) signal as a continuous auxiliary input in a complex instrumentation setup. This paper proposes an automatic segmentation method that does not require any such auxiliary signal. Compared to other approaches without auxiliary signal, this work extensively utilizes biomedical domain features for reduction of time and computational complexities and is more accurate. The performance of the algorithm is evaluated for nine commonly occurring pathological cases and normal heart sound for various sampling frequencies, recording environments and age group of subjects. The proposed algorithm yields an overall accuracy of 97.47% and is compared with two competing techniques. In addition, the robustness of the algorithm is shown against additive white Gaussian noise contamination at various SNR levels.  相似文献   
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ObjectivePatients with obesity may experience less patient-centered care. We assessed whether medical students’ implicit/explicit weight-related attitudes and perceptions of normative attitudes are associated with patient-centered care for patients with obesity.MethodsThird and fourth year medical students (N = 111) at one medical school completed a survey and participated in a patient care scenario with a standardized patient with obesity. Encounters were coded for patient-centered behavior. Predictors of patient-centered behaviors were assessed.ResultsStudent perceptions that negative attitudes about patients with obesity are normative in medical school were significantly associated with poorer patient-centered behaviors, including lower attentiveness (b=?0.19, p = 0.01), friendliness (b=?0.28, p < 0.001), responsiveness (b=?0.21, p = 0.002), respectfulness (b=?0.17, p = 0.003), interactivity (b=?0.22, p = 0.003), likelihood of being recommended by observers (b=?0.34, p < 0.001), and patient-centeredness index scores (b=?0.16, p = 0.002). Student reported faculty role-modeling of discrimination against patients with obesity predicted lower friendliness (b=?0.16, p = 0.03), recommendation likelihood (b=?0.22, p = 0.04), and patient-centeredness index score (b=?0.12, p = 0.03).ConclusionsNegative normative attitudes and behaviors regarding obesity in the medical school environment may adversely influence the quality of patient-centered behaviors provided to patients with obesity.Practice implicationsEfforts to improve patient-centered communication quality among medical trainees may benefit from intervention to improve group normative attitudes about patients with obesity.  相似文献   
96.
A potential issue in current nerve guides is that they do not transmit electrical nerve impulses between the distal and proximal end of an injured nerve, i.e. a synapse. Conductivity is a desirable property of an ideal nerve guide that is being considered for peripheral nerve regeneration. Most conductive polymers reported for the fabrication of tissue engineering scaffolds, such as polypyrrole and polyaniline, are non-biodegradable and possess weak mechanical properties, and thus cannot be fabricated into 3D structures. Herein, we have designed a new nanocomposite material composed of dopamine, carbon nanofibers (CNF) and polycaprolactone (PCL) for the fabrication of nerve conduits, which facilitates the growth and migration of neurons toward the targeted end of an injured nerve. This support and navigation of the scaffold leads to better sensory and motor function. The results showed that the mechanical properties of the printed PCL increased by 30% in comparison with the pure PCL film, which is comparable with human nerves. The in vitro cell study of human glioma cells showed that the printed lines provided support for neural cell attachment, migration and differentiation toward the targeted end. In contrast, in the absence of printed lines in the scaffold, the cells attach and grow in random directions, forming a flower shape (cell cluster) on the surface of PCL. Thus, the proposed scaffold is a promising candidate for nerve guide application based on its signal transmission and navigating neurons in a correct pathway towards the targeted end.

Directional growth induced by dopamine-functionalized CNF-based nanocomposite ink printing.  相似文献   
97.
Digital microfluidic (DMF) platforms have contributed immensely to the development of multifunctional lab-on-chip systems for performing complete sets of biological and analytical assays. Electrowetting-on-dielectric (EWOD) technology, due to its outstanding flexibility and integrability, has emerged as a promising candidate for such lab-on-chip applications. Triggered by an electrical stimulus, EWOD devices allow precise manipulation of single droplets along the designed electrode arrays without employing external pumps and valves, thereby enhancing the miniaturization and portability of the system towards transcending important laboratory assays in resource-limited settings. In recent years, the simple fabrication process and reprogrammable architecture of EWOD chips have led to their widespread applications in food safety analysis. Various EWOD devices have been developed for the quantitative monitoring of analytes such as food-borne pathogens, heavy metal ions, vitamins, and antioxidants, which are significant in food samples. In this paper, we reviewed the advances and developments in the design of EWOD systems for performing versatile functions starting from sample preparation to sample detection, enabling rapid and high-throughput food analysis.  相似文献   
98.
IntroductionDissection of regional lymph nodes (RLNs) can lead to significant morbidity and a high prevalence of complications. Published guidance states that these procedures should be carried out by surgeons who are members of a specialist skin multidisciplinary team who carry out a combined minimum of 15 axillary/groin dissections per year. However, there is little evidence to guide this minimum figure of procedures. We report on the burden of service provision and prevalence of complications across the South West of England and Wales.MethodsA 12-month review of dissections of RLNs for skin cancer was undertaken covering five Plastic Surgery Units with a collective catchment of 8.4 million people. Detailed data were collected on patient demographics, pathology, timing of surgery, and prevalence of complications.ResultsA total of 163 dissections were carried out. Forty-three per cent of patients experienced one or more complication. In that 12-month period, an average of 8 axillary/groin dissections was carried out per surgeon. A funnel plot demonstrated that the prevalence of complications for individual surgeons was within the limit of the plot but, in many cases, this was based only on a relatively small number of procedures per consultant. If surgeons carried out 10 procedures per year, the upper and lower limits on the plot were 73% and 11%, respectively.ConclusionsFunnel plots can provide a useful guide as to whether the prevalence of complications for procedures for individual surgeons lies within acceptable limits. Based on these results, 10 procedures per consultant per year should be sufficient to enable meaningful assessment of the prevalence of complications.  相似文献   
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100.
Current techniques for the detection of recurrent coronary stenoses following bypass grafting have shown disappointing diagnostic accuracy. This study used the same dipyridamole-handgrip stress to compare the accuracy of rubidium-82 positron emission tomography and thallium-201 single photon emission computed tomography, in 50 consecutive post-bypass patients undergoing coronary arteriography at a mean interval of 6.5 years after surgery. Significant stenoses in native coronary vessels (greater than 50% diameter) or grafts (greater than 70% diameter) were defined by quantitative angiography. Forty-six patients had recurrent or residual stenoses, 43 (93%) had a perfusion defect identified by positron emission tomography, and 35 (76%) were identified by single photon emission computed tomography (P = 0.04). Fourteen of the 17 patients (82%) without previous Q-wave myocardial infarction were identified by positron emission tomography; 10 of the 17 (59%) were detected by single photon emission computed tomography (P = NS). Stress-induced perfusion defects were demonstrated by positron emission tomography in 19 patients; of this group, thallium imaging identified reversible defects in 11, showed no perfusion defect in 1, and portrayed a persistent defect in 7 patients. Significant graft disease was present in 33 patients; perfusion defects were identified by positron emission tomography in 30 (91%), and by single photon emission computed tomography in 24 (73%, P = NS). Four patients were fully revascularized, without significant recurrent coronary disease; normal perfusion was present in 3 (75%) by positron emission tomography, and 4 (100%) by single photon emission computed tomography.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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