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1.
基于高阶累计量的肺音信号AR模型参数和双谱估计   总被引:2,自引:0,他引:2  
根据肺音信号的非高斯随机特性,建立了肺胸系统非高斯AR模型.应用高阶累积量技术对肺音信号进行参数化双谱估计,并提取肺音源特征和肺胸系统传递函数.实验结果证实:肺音源由非高斯白噪声、周期脉冲序列和间歇性随机脉冲组成,肺胸系统相当于声低通滤波器,不同病理情况下的肺音双谱结构存在明显差异.该方法克服了肺音信号功率谱分析和经典双谱分析的缺陷与不足,可以为肺部疾病诊断提供更多和更客观的内在信息.  相似文献   

2.
肺音信号分析系统研制   总被引:2,自引:0,他引:2  
本文研制的肺音信号检测与分析系统,具有肺音信号采集、肺音图显示、肺音信号的 时域分析等项功能。  相似文献   

3.
基于声门下嗓音源的肺胸系统声传递特征研究   总被引:1,自引:1,他引:0  
本文根据嗓音--呼吸系统生理及生物物理原理,提出了传导语音产生及在下声道和肺胸系统传播的物理模型,在胸前颈下V型槽处记录传导语音并利用复倒谱技术提取声门下噪音源,可以看出它非常有效地提取了声门下嗓音源,根据所提出的模型、提取的声门下噪声源和胸壁记录的传导语音,研究肺胸系统的声传递特征,从结果可以看出该方法是研究肺胸系统声传递特征函数的一种有效方法。  相似文献   

4.
不同状态下脑电信号的双谱分析   总被引:2,自引:0,他引:2  
根据脑电的非高斯随机特性,应用双谱技术分析脑电信号,引出脑电的参数化双谱估计,旨在克服脑电功率谱分析的缺陷。对四种不同脑功能状态(清醒闭眼、安神睁眼、快速心算、急促呼吸)的脑电进行双谱分析,并对对称脑电信号的互双谱作了初步的讨论。实验结果显示:所有脑电均出现明显的双谱结构,但不同生理状态下的脑电双谱结构存在明显的差异,结果表明双谱可能为研究脑电提供新的辅助信息。  相似文献   

5.
市场上的电子血压计一般均采用示波法,采用间接测量原理,其准确性难以提高。柯氏音法是血压测量的金标准,有望提高自动血压测量准确性,但柯氏音的降噪和识别是难题。因此,提出了基于柯氏音识别法的自动血压测量系统,该系统解决了降噪和识别的难题,通过对实时柯氏音信号的测试表明该系统可以有效地识别出柯氏音,得出收缩压和舒张压,识别精度高。且该系统成本低廉,测试实验均造作于Android系统的手机上,易于实现社区血压的健康管理和远程监控。  相似文献   

6.
颞下颌关节(TMJ)是人体最复杂的关节之一,有着复杂的生理功能,颞下颌关节音(颚开合时TMJ产生的声音)含有丰富的有关TMJ状态的信息。利用非线性动力学的混沌与分形理论对健康人和颞下颌关节内紊乱(TMD)患者的TMJ音信号进行了分析。分别计算其波形维和相关维。结果表明,健康人TMJ音信号的两种分形维数值都明显高于TMD患者。提示,以TMJ音信号的分形维数值作为TMJ损伤及病变的一个指标是有意义的。  相似文献   

7.
天牛类幼虫特征是探讨天牛总科演化和分类系统的重要依据。长期以来由于未找到狭胸天牛幼虫,其地位难以确定,影响到天牛总科分类系统的重建。近年来,在中国广西和西藏发现的猜胸天牛Philus antennatus (Gyllenhal)和细点音天牛Het-erophilus punctulatus Ching et Chen幼虫,为研究猜胸天牛分类地位提供了新的证据。综合比较认为,猜胸天牛与暗天牛科最相近,倾向于将狭胸天牛亚科归和暗天牛科。  相似文献   

8.
1临床资料 患儿,男,10岁,于2009年6月25日入住我院小儿科。9d前无明显诱因出现发热、咳嗽(当日外周血白细胞11.5×10^9/L,中性粒细胞72.4%),在外院抗感染治疗无效,并伴胸闷、气短、心悸转入我院。入院查体,呼吸音粗,双肺可闻及少许细湿罗音和干罗音,伴少许喘鸣音;胸片可见双肺斑片状影,边界不清,呈“蝴蝶翼”样,  相似文献   

9.
目的研究锌指转录因子Slug、E-cadherin和Vimentin在非小细胞肺癌恶性胸水细胞中的表达。方法应用免疫细胞化学和western blot检测Slug、E-cadherin和Vimentin在非小细胞肺癌胸水中的表达。结果在121例非小细胞肺癌胸水中,Slug、E-cadherin和Vimentin的阳性表达率分别为35.5%(43/121)、71.9%(87/121)和39.71%(48/121),在非小细胞肺癌细胞中Slug和E-cadherin阳性表达率均高于正常胸水,Slug表达的增强通常伴随E-cadherin表达下调及Vimentin表达的增强。结论 Slug与E-cadherin在胸水中非小细胞肺癌细胞中的表达呈负相关,在胸水中提取非小细胞肺癌细胞,研究Slug和E-cadherin,Vimentin的表达及其在上皮间质转化中的调节作用对探讨肿瘤细胞在人体中的转移进展很有意义。  相似文献   

10.
都柏林沙门氏菌能引起沙门氏菌病,近年来国内由该菌感染的病例较为少见。1991年11月我院收一7岁男孩,因头痛7天入院。入院时症状:体温41℃、弛张热型、昏迷、尿黄、便稀。体征:面色黄、巩膜无黄染、咽部充血、双扁桃体肿大Ⅰ°、双肺呼吸音粗糙,肝肋下2.5cm、脾肋下3cm质软,胸、腹部出现数处瘀点。化验:RBC3.6×10~(12)/L、Hb105g/L、WBC1.65×10~9/L、中性粒细胞78%、淋巴细胞20%、单核细胞2%。  相似文献   

11.
The spectral content of normal tracheal and chest wall breath sounds has been calculated using the fast Fourier transform (FFT) (J. Appl. Physiol. 50: 307-314, 1981). Parameter estimation methods, in particular autoregressive (AR) modeling, are alternative techniques for measuring lung sounds. The outcome of AR modeling of 38 complete breaths picked up simultaneously over the chest walls and tracheae of five normal males was evaluated. The sounds were treated as noise, bounded by a quasi-periodic envelope generated by the cyclic action of breathing, thus causing the sounds to become inherently nonstationary. Normalization of the sounds to their corresponding variance envelopes eliminated the nonstationarity, an important requirement for most signal-processing methods. Subsequently, the AR model order was sought using formal criteria. Orders 6-8 were found to be suitable for normal chest wall sounds, whereas tracheal sounds required at least orders 12-16. Using orders 6 and 12, we compared the prominent spectral features of chest wall and tracheal sounds calculated by AR with those found in the spectra calculated by FFT. The polar representation of the AR roots, calculated from the AR coefficients, showed that normal lung sounds from a group of individuals are characterized by a low variability, suggesting that this method may provide an alternative representation of the sounds. The data presented here show that normal lung sounds, when measured in the frequency domain by either FFT or AR modeling, have a characteristic pattern that is independent of the analysis method.  相似文献   

12.
本文测定了不同运动条件下的大鼠骨骼肌中的雄激素受体(androgenreceptor,AR)结合容量及雄激素的水平。一次力竭运动可使大鼠股四头肌组织的雄激素结合容量水平上升,但降低了其组织中的雄激素水平。在长期力竭性运动后,股四头肌组织雄激素受体结合容量及雄激素水平均没有变化,而长期的适宜运动则可提高股四头肌的雄激素结合容量的水平,但对其雄激素的水平仍无影响。通过机体注射HCG(人促绒毛膜性腺激素),可提高骨骼肌组织的雄激素水平,但骨骼肌雄激素受体结合容量水平没有变化。连续注射HCG4天,其骨骼肌组织雄激素水平显著高于连续注射HCG8天的水平。根据上述结果,我们认为,在考虑骨骼肌同化过程时,不但要注意其雄激素的水平,还应注意其雄激素受体的水平。运动对骨骼肌组织的雄激素受体结合容量及骨骼肌雄激素分布的影响是双向的  相似文献   

13.
ABSTRACT

The method usually used to identify different sounds or divisions of sounds is to compare sonagrams visually. There have been some attempts to reduce the subjectivity and increase the repeatability of this approach, for example by tracing the sonagrams onto paper and examining the areas of overlap and mismatch, the use of multi-variate statistics and digitising tablets. Digital recording of sounds has allowed sounds to be input directly into computers which can be used to display sounds and facilitate measurement. To date there has been little attempt at their use for analysis. We outline a series of programs which have been developed to compare statistically any unit of a sound with a pre-recorded library of similar units. The creation of such a library allows the rapid and objective categorisation of large numbers of sounds. These programs have been used to analyse songs recorded from wrens Troglodytes troglodytes and house crickets Acheta domesticus. Potential applications of this software to the field of bioacoustic investigation are discussed.  相似文献   

14.
The two-year survival rate of patients with small cell lung cancer is less than 10%. The major reason for this poor outcome is the development of drug resistance. Panels of small cell lung cancer cell lines have been established, providing models for the study of drug resistance in this tumour. One such model is the doxorubicin-selected H69AR cell line. H69AR displays the typical multidrug resistance phenotype in that it is cross-resistant to anthracyclines, Vinca alkaloids (e.g., vinblastine) and epipodophyllotoxins (e.g., VP-16). However, H69AR cells do not overexpress P-glycoprotein, the membrane drug efflux pump frequently found on multidrug resistant cells. Some alterations in glutathione levels and associated enzyme activities were found but the data do not support the notion that enhanced drug detoxication is involved in H69AR cell resistance. Fewer drug-induced DNA strand breaks, reduced levels of topoisomerase II, and reduced formation of drug-stabilized DNA/topoisomerase II complexes were observed in H69AR cells. These data implicate topoisomerase II in the resistance phenotype of H69AR cells, but cannot explain H69AR cell resistance to the Vinca alkaloids, which do not have topoisomerase II as a target. Monoclonal antibodies against antigens overexpressed on H69AR cells have been derived and four have been characterized. Immunoscreening of an H69AR cDNA expression library has allowed the identification of one of these antigens as p36 (annexin II), a Ca2+/phospholipid binding protein. Chemosensitizers and novel xenobiotics have been examined for their ability to circumvent the drug resistance of H69AR cells. The limited success of these investigations suggests that innovative approaches may be required. In conclusion, the data obtained with H69AR and other models of small cell lung cancer indicate that multiple mechanisms contribute to drug resistance in this disease.  相似文献   

15.
雄激素受体在肝癌发生过程中的表达及意义   总被引:1,自引:0,他引:1  
为了进一步探讨雄激素受体(AndrogenReceptor,AR)作为肝癌标志物的意义,本文采用免疫组织化学ABC法,对二乙基亚硝胺(DEN)诱发大鼠肝癌发生过程中肝细胞雄激素受体(AR)的表达进行了系统观察。结果显示:正常大鼠的AR阳性肝细胞极少,DEN诱癌第4周可见少量肝细胞呈AR阳性表达,细胞散在分布,胞质和/或胞核内可见棕褐色阳性反应颗粒。随着肝癌发展进程,AR阳性肝细胞数逐渐增多,呈簇状或片状分布。至诱癌第18周,肝癌结节内肝癌细胞大多呈AR阳性表达。本实验结果表明,AR与肝癌的发生和发展具有密切关系  相似文献   

16.
Auscultation is an important, non-invasive and simple measure in the diagnosis of lung diseases that can detect sometimes pathological processes prior to radiography. Attempts have already been made to automatically detect characteristic pathological sounds, but a knowledge of potential influencing factors is a must for correct interpretation. In this study we have investigated the effect of the subcutaneous fat layer on normal lung sounds. This is of importance to determine corrective factors for the automatic detection of bronchial breathing in pneumonia. The lung sounds of 125 healthy people (55f, 70m) were digitally recorded at four different positions of the thorax (3. ICR paravertebral, 7. ICR medioscapular, all left and right). Evaluation was done separately for gender. The subcutaneous fat layer was measured with a Holtain Skinfold Caliper at the identical four recording positions. For a quantitative evaluation of the sounds we calculated the relative power of frequency bands 330-600 Hz and 60-330 Hz and their ratio. The relation between these parameters and the subcutaneous fat layer was analyzed with the Pearson correlation. The results of this study show that the influence of subcutaneous fat layer is negligible and can be ignored in the automatic detection of lung sounds.  相似文献   

17.
IAN M. KING 《Bioacoustics.》2013,22(4):297-324
ABSTRACT

This is the first reported study of corixid water bugs examining whether all species of a genus in one locality can be distinguished by their sounds. More extensive analysis than has been reported for any corixids revealed that, although some species are difficult to distinguish morphologically, inter-species sound differences are very clear.

The sounds of all nine species of Micronecta in the study area near Melbourne, Australia were recorded. Male sounds were recorded in the laboratory, over a minimum water temperature range of 15 to 25°C. Females do not produce sounds. Signals consisted of groups of pulse-trains, except for one species with signals of usually one pulse-train. Signals were species-specific; pulse-train rate alone was sufficient to distinguish between species. There were also species differences in other signal parameters. Males also produced clicks (single pulse-trains) and low-amplitude sounds; there were some species differences in the latter. Similar signals occurred between only one pair of species, which were from different habitats (ponds and rivers). Pulse periods and pulse-train periods were negatively correlated with temperature, with curves of best fit being quadratic. Five species were also recorded in ponds; the sounds and effect of temperature were compared with laboratory recordings.  相似文献   

18.

Background  

Voice disorders affect patients profoundly, and acoustic tools can potentially measure voice function objectively. Disordered sustained vowels exhibit wide-ranging phenomena, from nearly periodic to highly complex, aperiodic vibrations, and increased "breathiness". Modelling and surrogate data studies have shown significant nonlinear and non-Gaussian random properties in these sounds. Nonetheless, existing tools are limited to analysing voices displaying near periodicity, and do not account for this inherent biophysical nonlinearity and non-Gaussian randomness, often using linear signal processing methods insensitive to these properties. They do not directly measure the two main biophysical symptoms of disorder: complex nonlinear aperiodicity, and turbulent, aeroacoustic, non-Gaussian randomness. Often these tools cannot be applied to more severe disordered voices, limiting their clinical usefulness.  相似文献   

19.
When courting, males of the Drosophila virilis group vibrate their wings and emit species-specific courtship sounds consisting of trains of polycyclic sound pulses. To analyze the genetic basis of evolutionary changes in the sounds we made an F1 diallel set of reciprocal crosses between the members of the virilis phylad of the group (two stocks of D. virilis and one of D. americana americana, D. a. texana, D. novamexicana, and D. lummei). We also crossed the D. virilis stocks with the members of the montana phylad of the same group (D. kanekoi, D. littoralis, D. borealis, D. flavomontana, D. lacicola, and D. montana) and made a backcross (D. virilis x D. littoralis) x D. virilis using a D. virilis marker stock (b; sv t tb gp; cd; pe). The sounds of the hybrids were analyzed using the following parameters: the length of a pulse train (PTL), the number of pulses in a train (PN), the interpulse interval (IPI), the length of a pulse (PL), the number of cycles in a pulse (CN), and the length of a cycle (CL). In the virilis phylad, the differences between species appeared to be determined mainly by autosomal genes in each sound trait. The heritabilities (narrow-/broad-sense) obtained from the diallel tables were the following: PTL 0.662/0.817, PN 0.651/0.841, IPI 0.193/0.546, PL 0.408/0.552, CN 0.425/0.719, and CL 0.361/0.764. The direction of dominance is for longer PTL, higher PN and CN, and shorter IPI and CL. PL shows ambidirectional dominance. In the sounds of the virilis phylad species, PTL and PL seem to be phenotypically the most important parameters, since their components (PN and IPI for PTL, CN and CL for PL) are negatively correlated. In crosses between D. virilis and D. littoralis or D. flavomontana reciprocal hybrids differed from each other in PTL, IPI, PL, and CN indicating X-chromosomal or cytoplasmic inheritance. In the backcrosses between D. virilis and D. littoralis the role of the X chromosome was ascertained to be decisive. We conclude that an X-chromosomal major change allowing variation in IPI has occurred during the separation of the two D. virilis group phylads, the long IPI allowing variation also in PL (and CN). The evolution of the sounds in the virilis phylad has probably gone towards longer and denser pulse trains, while in the montana phylad the sounds have evolved in different directions.  相似文献   

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