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91.
Charcot-Marie-Tooth disease (CMT) is a heterogeneous disorder and is traditionally classified into two major types, CMT type 1 (CMT1) and CMT type 2 (CMT2). Most CMT1 patients are associated with the duplication of 17p11.2-p12 (CMT1A duplication) and small numbers of patients have mutations of the peripheral myelin protein 22 (PMP22), myelin protein zero (MPZ), connexin 32 (Cx32/GJB1), and early growth response 2 (EGR2) genes. Some mutations of MPZ and Cx32 were also associated with the clinical CMT2 phenotype. We constructed denaturing gradient gel electrophoresis (DGGE) analysis as a screening method for PMP22, MPZ, and Cx32 mutations and studied 161 CMT patients without CMT1A duplication. We detected 27 mutations of three genes including 15 novel mutations; six of PMP22, three of MPZ, and six of Cx32. We finally identified 21 causative mutations in 22 unrelated patients and five polymorphic mutations. Eighteen of 22 patients carrying PMP22, MPZ, or Cx32 mutations presented with CMT1 and four of them with MPZ or Cx32 mutations presented with the CMT2 phenotype. DGGE analysis was sensitive for screening for those gene mutations, but causative gene mutation was not identified in many of the Japanese patients with CMT, especially with CMT1. Other candidate genes should be studied to elucidate the genetic basis of Japanese CMT patients. 相似文献
92.
心电信号预处理与心电信号分析 总被引:2,自引:0,他引:2
本文介绍了在一种便携式心电监护仪器中是如何对心电数据进行预处理和智能分析的.为了适应便携式仪器的特征,我们在心电信号预处理中采用了FFT滤波和滑动平均滤波的方法去除各种干扰并使图像得以平滑,同时采用了差分阈值法提取特征点,考虑到监护仪器的实用性,在心电信号分析阶段,我们采用了分析特征间期异常情况的方法来替代对病症的智能诊断功能。 相似文献
93.
Fuzzy rules to predict degree of malignancy in brain glioma 总被引:2,自引:0,他引:2
Ye CZ Yang J Geng DY Zhou Y Chen NY 《Medical & biological engineering & computing》2002,40(2):145-152
The current pre-operative assessment of the degree of malignancy in brain glioma is based on magnetic resonance imaging (MRI)
findings and clinical data. 280 cases were studied, of which 111 were high-grade malignancies and 169 were low-grade, so that
regular and interpretable patterns of the relationships between glioma MRI features and the degree of malignancy could be
acquired. However, as uncertainties in the data and missing values existed, a fuzzy rule extraction algorithm based on a fuzzy
min-max neural network (FMMNN) was used. The performance of a multi-layer perceptron network (MLP) trained with the error
back-propagation algorithm (BP), the decision tree algorithm ID3, nearest neighbour and the original fuzzy min-max neural
network were also evaluated. The results showed that two fuzzy decision rules on only six features achieved an accuracy of
84.6% (89.9% for low-grade and 76.6% for high-grade cases). Investigations with the proposed algorithm revealed that age,
mass effect, oedema, post-contrast enhancement, blood supply, calcification, haemorrhage and the signal intensity of the T1-weighted
image were important diagnostic factors. 相似文献
94.
听觉诱发电位提取方法的研究与分析 总被引:2,自引:0,他引:2
论述了运用小波变换进行听觉诱发电佗单次提取的原理、方法和实验分析。结果表明,对单次试验信号,经小波变换及相关分析后,可从带自发脑电干扰的信号中提取诱发电位信号。小波变换分析方法与传统的叠加平均方法相比,可减少试验次数,缩短检测周期。 相似文献
95.
一种测量牙松动度的新方法 总被引:5,自引:0,他引:5
本文是出了一种客观确定牙松动的新方法。用瞬态碰撞激震测定牙固有振动半周期T/2和减幅系数η。以T/2为主,η为辅,度量牙齿的松动度。对依据的原理从牙周动力学模型出发进行了严密的数学推导;讨论了测试方案;介绍了牙模型测试实验;最后给出实际状态下测试的初步结果。 相似文献
96.
De Vos A Sermon K De Rijcke M Goossens V Henderix P Van Ranst N Platteau P Lissens W Devroey P Van Steirteghem A Liebaers I 《Molecular human reproduction》2003,9(7):429-435
Charcot-Marie-Tooth (CMT) disease is the 'common' name for a range of hereditary peripheral neuropathies. CMT1 is the most common form and is transmitted in an autosomal dominant manner. CMT1A maps to chromosome 17p11.2 and is caused, in the majority of cases, by a 1.5 Mb DNA duplication, that includes the peripheral myelin protein 22 (PMP) gene. This paper reports on preimplantation genetic diagnosis (PGD) for CMT1A in five couples. The CMT1A duplication was detected by fluorescent PCR analysis using polymorphic (CA)n markers localized within the duplication. Single-cell PCR on blastomeres allowed genetic analysis of embryos obtained after ICSI. Only healthy unaffected embryos were transferred to the uterus. PCR experiments with single EBV-transformed lymphoblasts or with research blastomeres allowed the evaluation of amplification efficiencies, as well as contamination and allele drop-out (ADO) rates for each PCR protocol. Three simplex PCR protocols (using one primer pair) and two duplex PCR protocols (using two primer pairs) were developed for CMT1A. Additionally, a protocol using all three primer pairs in triplex was also established. Thirteen clinical ICSI-PGD cycles were performed for five couples (12 simplex PCR cycles and one duplex PCR cycle), resulting in seven embryo transfers. Three singleton pregnancies ensued in two couples and three healthy babies were delivered. This report describes different fluorescent PCR-based tests which allow efficient and accurate single-cell level detection of the CMT1A duplication. On the basis of the presence of the healthy allele of the affected parent-to-be (and/or absence of the affected one), healthy embryos can be selected for transfer. The assays are suitable for PGD for other couples who present with the same CMT1A duplication [depending on their informativity for the (CA)n markers available] as described here. 相似文献
97.
Puttemans ML Dryon L Massart DL 《Journal of pharmaceutical and biomedical analysis》1985,3(6):503-510
Synthetic dyes were extracted from syrups, oral suspensions, tablets, gelatin capsules, suppositories and granules by ion-pair formation with tri-n-octylamine (TnOA) and back-extracted with perchlorate ions. Identification was performed by TLC on cellulose layers and by reversed phase ion-pair HPLC. 相似文献
98.
目的 建立蜂蜜中氯霉素、甲砜霉素、氟甲砜霉素及甲硝唑残留的高效液相色谱-串联质谱同时测定方法。方法 以乙酸乙酯作为提取剂,经涡旋混匀提取后,氮吹至干,用5%甲醇水溶解,Oasis HLB固相萃取柱净化。经甲醇洗脱,洗脱液经45℃水浴氮吹至干,流动相涡旋溶解,上机测定。高效液相色谱分离、串联质谱检测,采用多离子反应监测(MRM)模式,内标法定量。结果 在优化条件下,4种抗生素浓度在0.1~5.0μg/L范围内,线性关系良好,相关系数(r)≥0.9953,方法检出限≤0.015μg/kg,不同基质中平均加标回收率为78.5%~95.1%,相对标准偏差(RSD)为2.8%~10.7%。结论 该方法快速、灵敏、准确,适用于蜂蜜中氯霉素、甲砜霉素、氟甲砜霉素及甲硝唑的同时测定。 相似文献
99.
目的探讨优化牙支持式上颌骨前部牵引成骨术与上颌骨Le FortⅠ型前徙术治疗唇腭裂患者的效果,以及对其腭咽部结构的影响。方法将大连市口腔医院2017年1月一2020年1月收治的63例唇腭裂伴上颌骨发育不足患者纳人研究,依据随机数字表法分为观察组31例和对照组32例。对照组实施上颌骨Le FortⅠ型前徙术治疗,观察组实施优化牙支持式上颌骨前部牵引成骨术治疗。比较并分析两组治疗前后腭咽部形态参数、上颌骨前移距离、吹气试验和语言清晰度测听结果。采用Pearson相关性分析明确上颌骨前移距离与腭咽部形态各项参数之间的关系。结果治疗后观察组静止位的腭咽腔深度低干对照组,差异有统计学意义(P<0.05);两组治疗前后腭咽部形态其余各项参数及上颌骨前移距离,差异均无统计学意义(P>0.05)。治疗后观察组不捏鼻、捏鼻吹气试验时间均短干对照组,语言清晰度高干对照组,差异均有统计学意义(P〈O.O5)。Pearson相关性分析显示,上颌骨前移距离与各项腭咽部形态参数均无相关性(P>0.05)。结论优化牙支持式上颌骨前部牵引成骨术与上颌骨Le FortⅠ型前徙术治疗唇腭裂均有效,但是,优化牙支持式上颌骨前部牵引成骨术相较于上颌骨Le FortⅠ型前徙术,对患者腭咽部结构影响较小,值得推荐采用。 相似文献
100.
1932例拔牙后出血临床分析 总被引:2,自引:0,他引:2
目的 探讨拔牙后出血的原因及急诊处理的方法。方法 回顾性分析1932例拔牙后出血急诊患者的出血原因及处理方法。结果 本组病例病因主要有软组织撕裂350例(18.1%),高血压340例(17.6%),牙槽窝内残留性肉芽组织及残留牙根270例(14%),其它972例。经口腔科急诊处理治愈1810例(93.7%),122例转入内科及血液科,其中120例痊愈,2例死亡。结论 拔牙后出血为口腔科常见的并发症,对其应以预防为主,急诊处理时应兼顾局部与全身,必要时会同内科医生进一步检查,明确病因,进行治疗。 相似文献