In order to solve imperfection of heart rate extraction by method of traditional ballistocardiogram (BCG), this paper proposes an improved method for detecting heart rate by BCG. First, weak cardiac activity signals are acquired in real time by embedded sensors. Local BCG beats are obtained by signal filtering and signal conversion. Second, the heart rate is estimated directly from the BCG beat without the use of a heartbeat template. Compared with other methods, the proposed method has strong advantages in heart rate data accuracy and anti-interference, and it also realizes non-contact online detection. Finally, by analyzing the data of more than 20,000 heart rates of 13 subjects, the average beat error was 0.86% and the coverage was 96.71%. It provides a new way to estimate heart rate for hospital clinical and home care.
【摘要】 目的 探讨全自动尿沉渣分析仪在尿管型检测中的应用。 方法 收集尿管型患者晨尿标本836份。所有标本均经尿干化学分析仪检测Pro≥1+或尿沉渣分析仪提示有管型。采用UF100全自动尿沉渣分析仪和显微镜检测管型，对比分析两者的检测结果。 结果 836份标本中，UF100全自动尿沉渣分析仪检测阳性者320例，占38.28%；显微镜检测阳性者195例，占23.33%。其中UF100全自动尿沉渣分析仪的假阳性率为26.52%，假阴性率为23.08%。UF100尿沉渣分析仪与显微镜检测管型的阳性结果比较，差异有统计学意义（Plt;0.01）。 结论 UF100全自动尿沉渣仪能快速筛检尿沉渣，但存在一定的假阴性，必须同时将其检测结果与尿干化学结果结合考虑以决定是否再进行显微镜检测，减少假阴性以防止漏检。【Abstract】 Objective To investigate the application of UF-100 full-auto urine sediment analyzer in detecting cylindruia. Methods 836 specimens with cylindruia were selected. All the specimens with Pro≥1+ were dectected by chemical dipstick or cylindruia by urine sediment analyzer. The cast were detected by urine sediment analyzer and microscope, and the results were compared. Results Of 836 specimens, 320 positive samples(38.28%) were found by UF-100 while 195 (23.33%) were found by microscope. False positive rate and false negative rate of UF100 were 26.52% and 23.08%. Compared the results of urine sediment analyzer with microscope, the difference was statistically significant (Plt;0.01). Conclusions UF100 can detect urinary cast quickly, but there is a little high false negative rate. So we should consider urine sample whether to be detected by microscope compared with results of UF100 and chemical dipstick.
Amanitin-containing mushroom poisoning is one of the most harmful and lethal types of mushroom poisoning events. Its basic medical and clinical medical knowledge has not been fully understood and mastered, so the basic and clinical diagnosis and treatment of amanitin-containing mushroom poisoning has always been a hot research field of acute mushroom poisoning. This article focuses on the new progress in the epidemiology, toxicological properties, poisoning mechanism, clinical diagnosis and treatment of amanitin-containing mushroom poisoning, in order to provide the basis for further study, diagnosis and treatment of amanitin-containing mushroom poisoning for basic researchers and clinical medical staff.
Hepatitis C virus (HCV) do harm to people's health. The present study aims to establish a simple HCV detection method by reverse transcription-loop mediated isothermal amplification technique (RT-LAMP). A total of 75 clinical samples were collected and pre-detected by fluorescence quantitative-polymerase chain reaction (FQ-PCR), which was considered as the gold standard. Firstly, four common primers were designed according to the conservative 5'UTR region of HCV on the NCBI website to establish an integrated RT-LAMP reaction system. Then, the reaction efficiency was evaluated by adding Taq DNA polymerase to the conventional system. The specificity of RT-LAMP was evaluated by observing the length of fragment after endonuclease digestion and by a templates exchange assay, the sensitivity of RT-LAMP was evaluated by detection of diluted clinical templates. The results were compared with that of reverse transcription polymerase chain reaction (RT-PCR). At the same time, the performance was judged using calcein and hydroxynaphthol blue (HNB) stain methods, The two results were compared with that of electrophoresis method. At last, 75 clinical samples were detected by both RT-LAMP and RT-PCR methods. Results showed that the reaction efficiency was increased 20 minutes after adding Taq DNA polymerase to the normal RT-LAMP system. RT-LAMP showed good specificity, the digestion length was consistent with our expectation (216 bp) after restriction endonuclease cleavage assay, and only the templates of HCV were amplified using the common RT-LAMP primers. After detection of diluted temples, the sensitivity of RT-LAMP was 10 IU/tube, which was 10 fold higher than that of PCR. In addition, the results using calcein and HNB stain methods were the same with that of electrophoresis method. After detection of all 75 clinical samples, the results indicated that RT-LAMP had worse consistency with RT-PCR (P < 0.05, Kappa=0.375). However, RT-LAMP, on the contrary, showed good consistency with FQ-PCR (P > 0.05, Kappa=0.762). In conclusion, RT-LAMP has characteristics of simplicity, specificity and sensitivity, and this technique is suitable for the primary care hospitals.
Medical magnetic nanoparticles are nano-medical materials with superparamagnetism, which can be collected in the tumor tissue through blood circulation, and magnetic particle imaging technology can be used to visualize the concentration of magnetic nanoparticles in the living body to achieve the purpose of tumor imaging. Based on the nonlinear magnetization characteristics of magnetic particles and the frequency characteristics of their magnetization, a differential detection method for the third harmonic of magnetic particle detection signals is proposed. It was modeled and analyzed, to study the nonlinear magnetization response characteristics of magnetic particles under alternating field, and the spectral characteristics of magnetic particle signals. At the same time, the relationship between each harmonic and the amount of medical magnetic nanoparticle samples was studied. On this basis, a signal detection experimental system was built to analyze the spectral characteristics and power spectral density of the detected signal, and to study the relationship between the signal and the excitation frequency. The signal detection experiment was carried out by the above method. The experimental results showed that under the alternating excitation field, the medical magnetic nanoparticles would generate a spike signal higher than the background sensing signal, and the magnetic particle signal existed in the odd harmonics of the detected signal spectrum. And the spectral energy was concentrated at the third harmonic, that is, the third harmonic magnetic particle signal detection that meets the medical detection requirement could be realized. In addition, the relationship between each harmonic and the particle sample volume had a positive growth relationship, and the detected medical magnetic nanoparticle sample volume could be determined according to the relationship. At the same time, the selection of the excitation frequency was limited by the sensitivity of the system, and the detection peak of the third harmonic of the detection signal was reached at the excitation frequency of 1 kHz. It provides theoretical and technical support for the detection of medical magnetic nanoparticle imaging signals in magnetic particle imaging research.
To realize the accurate positioning and quantitative volume measurement of tumor in head and neck tumor CT images, we proposed a level set method based on augmented gradient. With the introduction of gradient information in the edge indicator function, our proposed level set model is adaptive to different intensity variation, and achieves accurate tumor segmentation. The segmentation result has been used to calculate tumor volume. In large volume tumor segmentation, the proposed level set method can reduce manual intervention and enhance the segmentation accuracy. Tumor volume calculation results are close to the gold standard. From the experiment results, the augmented gradient based level set method has achieved accurate head and neck tumor segmentation. It can provide useful information to computer aided diagnosis.
In order to solve the saturation distortion phenomenon of R component in fingertip video image, this paper proposes an iterative threshold segmentation algorithm, which adaptively generates the region to be detected for the R component, and extracts the human pulse signal by calculating the gray mean value of the region to be detected. The original pulse signal has baseline drift and high frequency noise. Combining with the characteristics of pulse signal, a zero phase digital filter is designed to filter out noise interference. Fingertip video images are collected on different smartphones, and the region to be detected is extracted by the algorithm proposed in this paper. Considering that the fingertip’s pressure will be different during each measurement, this paper makes a comparative analysis of pulse signals extracted under different pressures. In order to verify the accuracy of the algorithm proposed in this paper in heart rate detection, a comparative experiment of heart rate detection was conducted. The results show that the algorithm proposed in this paper can accurately extract human heart rate information and has certain portability, which provides certain theoretical help for further development of physiological monitoring application on smartphone platform.
Multivariate time series problems widely exist in production and life in the society. Anomaly detection has provided people with a lot of valuable information in financial, hydrological, meteorological fields, and the research areas of earthquake, video surveillance, medicine and others. In order to quickly and efficiently find exceptions in time sequence so that it can be presented in front of people in an intuitive way, we in this study combined the Riemannian manifold with statistical process control charts, based on sliding window, with a description of the covariance matrix as the time sequence, to achieve the multivariate time series of anomaly detection and its visualization. We made MA analog data flow and abnormal electrocardiogram data from MIT-BIH as experimental objects, and verified the anomaly detection method. The results showed that the method was reasonable and effective.
Neurosyphilis is a group of clinical syndromes in which Treponema pallidum invades the nervous system and causes damage to the meninges, blood vessels, brain parenchyma or spinal cord. At present, there is no highly specific and sensitive method for the diagnosis of neurosyphilis, and its diagnosis mainly depends on clinical manifestations, abnormal cerebrospinal fluid and the comprehensive judgment of clinicians. Current studies show that some cytokines and chemokines are promising for laboratory detection of neurosyphilis. This article reviews the research progress of neurosyphilis from the aspects of traditional laboratory testing, polymerase chain reaction testing, cytokine and chemokine testing, and existing diagnostic criteria for neurosyphilis, in order to provide a reference for clinical testing and follow-up research.