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患有呼吸问题的病人由于呼吸道腺体不受意识控制、异物或者其本身肺部病变等原因会出现呼吸异常。医护人员通过病人的呼吸状况可以找寻和分析病人出现这种呼吸状况的原因。而以往呼吸声的诊断方式是专业的医护人员通过使用听诊器对病人进行肺部听诊。但是听诊的结果取决于医护人员的经验与相关参数。在初级诊断治疗阶段,初级医生识别听诊声的效率以及准确率很低,一般从20%到80%不等。因此会存在10%到20%的高误诊率(漏诊、错诊和延误)。本文提出了一种利用PVDF薄膜传感器提取语声特征的检测系统,该检测系统根据病人发出声音的不同,提取呼吸声特征值判断病人的呼吸状况。通过PVDF传感器采集的微弱呼吸声再经过KNN算法分类之后其识别率可达90.6%,对于细分种较类多的湿罗声,其识别率在80.2%左右。综上表明相比于传统听诊方式通过PVDF传感器采集识别的结果具有更高的准确性和可靠性,其判断呼吸状况的结果可以为医护人员提供参考,更好的为患有呼吸疾病的病人提供监测。  相似文献   
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贺殿  杨竹青  侯猛 《结构化学》2014,33(9):1388-1394
The new title compound 4-chloro-N-(2-(2-nitrophenyl)acetoxy)-N-(m-tolyl)benzamide(C22H17ClN2O5, Mr = 424.82) has been synthesized via the reaction of 4-chloro-N-hydroxy-N-(m-tolyl)benzamide with 2-(2-nitrophenyl)acetyl chloride. The structure of the product was confirmed by 1H NMR, 13 C NMR, IR, HRMS(ESI) and single-crystal X-ray diffraction. The title compound crystallizes in the monoclinic system, space group P21/c with a = 13.0269(10), b = 6.7251(6), c = 23.9313(16) , β = 99.931(6)o, V = 2065.1(3) 3, Z = 4, Dc = 1.366 g/cm3, F(000) = 880, μ = 0.221 mm-1, the final R = 0.0600 and wR = 0.1754 for 1981 observed reflections(I 2σ(I)). X-ray analysis indicates that the chloro-phenyl ring(C(10)~C(15)) and the methyl-substituted benzene ring(C(16)~C(21)) are not coplanar with the nitro-substituted benzene ring(C(1)~C(6)), with the dihedral angle to be 70.78° and 63.72°, respectively. Hydrogen bonds C(2)–H(2)···O(2) and C(7)–H(7B)···O(5) are observed.  相似文献   
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The title compound, N-(2-(1H-indol-3-yl)ethyl)-2-nitroaniline(C16H15N3O2, Mr = 281.31), has been synthesized by the multicomponent reaction of milder Ullmann, and its structure was characterized by 1H NMR, 13 C NMR, IR, H RMS(ESI) and single-crystal X-ray diffraction. It crystallizes in monoclinic, space group I2/c with a = 15.0212(10), b = 9.4911(6), c = 20.3075(13) A, β = 100.776(7)o, V = 2844.1(3)A3, Z = 8, Dc = 1.314 g/cm3, F(000) = 1184.0, μ = 0.089 mm-1, the final R = 0.0574 and w R = 0.1688 for 1701 observed reflections(I 2σ(I)). X-ray analysis indicates three major N(2)–H(2)···O(2), C(13)–H(13)···O(2), N(2)–H(2)···N(3) hydrogen bonds and π-π stacking interactions in the crystal structure. The preliminary biological test shows that the title compound has a good antitumor activity against A549 in vitro with the IC50 value of 35 μmol/L.  相似文献   
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