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1.
《International journal of oral and maxillofacial surgery》2022,51(3):332-337
The purpose of this study was to investigate the association between habitual snoring (HS), middle ear disease (MED), and speech problems in children with cleft palate. This cross-sectional study included children aged 2.0–7.9 years with non-syndromic cleft palate anomalies. Parents completed the Pediatric Sleep Questionnaire and a questionnaire about MED. Audiograms and speech assessment were also conducted. Ninety-five children were enrolled; 15.2% of families reported HS, 97.6% MED, and 17.1% speech problems. HS (37.5% vs 10.3%, P = 0.007) and early episodes of MED (92.3% vs 58.2%, P = 0.021) were more likely to be reported for children with isolated cleft palate when compared to those with cleft lip and palate. Children with cleft lip and palate had a higher frequency of MED with effusion compared to those with Robin sequence (86.4% vs 57.1%, P = 0.049). The odds ratio for HS in children with ≥1 episode of MED in the last year was 7.37 (95% confidence interval 1.55–35.15, P = 0.012). There was a trend for children with speech problems reported by parents to have HS (30.8% vs 11.5%, P= 0.076). Anatomical factors play a role in the frequency of upper airway symptoms in children with cleft palate. A recent history of at least one episode of MED was associated with an increased frequency of HS. 相似文献
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目的 了解解放军总医院抗震颤麻痹药物的应用情况与用药趋势。方法 采用世界卫生组织(WHO)推荐的以限定日剂量(DDD)为指标的分析方法,对2015-2017年解放军总医院抗震颤麻痹药物的销售金额、用药频度(DDDs)、日均费用(DDC)及排序比(B/A)等进行统计分析。结果 普拉克索、多巴丝肼和恩他卡朋的用药金额始终处于前3位,普拉克索的用药金额逐渐上升,卡比多巴/左旋多巴的用药金额逐渐下降;DDDs排序列前2位的是多巴丝肼和司来吉兰,多巴丝肼的DDDs逐年上升,一直处于第1位;2015-2016年各种抗震颤麻痹药物的DDC较为稳定,2016-2017年各种抗震颤麻痹药物的DDC开始略有下降;除普拉克索和恩他卡朋的B/A始终小于1.00,其他抗震颤麻痹药物的B/A均在1.00以上波动。结论 解放军总医院抗震颤麻痹药物的使用较为合理,其中多巴丝肼、普拉克索和司来吉兰具有很好的市场前景。 相似文献
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目的 克隆土耳其斯坦东毕吸虫磷酸丙糖异构酶的全长基因。方法 根据日本血吸虫和曼氏血吸虫磷酸丙糖异构酶基因的保守区设计引物,利用RT—PCR扩增出土耳其斯坦东毕吸虫磷酸丙糖异构酶基闪的大片段,再结合RACE技术分别得到磷酸丙糖异构酶基因的3’端和5’端,将3部分序列拼接后获得磷酸丙糖异构酶基因全长cDNA序列,并提交GenBank。结果 成功克隆了土耳其斯坦东毕吸虫磷酸丙糖异构酶基因全长cDNA序列并提交GenBank,登录号为DQ092331。结论 土耳其斯坦东毕吸虫磷酸丙糖异构酶基因全长cDNA的克隆为进一步表达及其生物学性能的分析提供了理论基础。 相似文献
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目的探讨p16基因突变在白血病发生中的作用及基因突变的机制。方法利用点突变检测仪、水平和垂直板电泳对p16基因的外显子1、外显子2的PCR扩增产物作缺失和点突变分析。结果在白血病35例临床标本中有22例发生缺失突变,6例发生点突变,突变率约80%。在22例缺失突变病例中,有10例为不完全缺失突变即有低于外显子509bp的扩增产物。结论p16基因含有“GC”DNA重复顺序,易发生DNA重组及易位和重排。在白血病发生中起重要作用 相似文献
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To explain how the myelin proteins are involved in the organization and function of the myelin sheath requires knowing their molecular structures. Except for P2 basic protein of PNS myelin, however, their structures are not yet known. As an aid to predicting their molecular folding and possible functions, we have developed a FORTRAN program to analyze the primary sequence data for proteins, and have applied this to the myelin proteins in particular. In this program, propensities for the secondary structure conformations as well as physical-chemical parameters are assigned to the amino acids and the pattern of these parameters is examined by calculating their average values, autocorrelation functions and Fourier transforms. To compare two proteins, their sequences are aligned using a unitary scoring matrix, and homologies are searched by plotting a two-dimensional map of the correlation coefficients. Comparison of the corresponding myelin basic proteins (MBP) and P0 glycoproteins (P0) for rodent and shark showed that the conserved residues included most of the amino acids which were predicted to form the alpha or beta conformations, while the altered residues were mainly in the hydrophilic and turn or coil regions. In both rodent and shark the putative extracellular domain of P0 glycoprotein displayed consecutive peaks of beta propensity similar to that for the immunoglobulins, while the cytoplasmic domain showed alpha-beta-alpha folding. To trace the immunoglobulin fold along the P0 sequence, we compared the beta propensity curve of P0 with that of the immunoglobulin M603, whose three-dimensional structure has been determined. We propose that the flat beta-sheets of P0 are orientated parallel to the membrane surface to facilitate their homotypic interaction in the extracellular space. An extra beta-fold in the extracellular domain of shark P0 compared with rodent P0 was found, and this may result in a greater attraction between the apposed extracellular surfaces and may account for a smaller extracellular space as measured by x-ray diffraction. A computer search of the myelin protein sequences for functional motifs revealed sites for N-glycosylation, phosphorylation, nucleotide binding, and certain enzyme activities. We note especially that there are potential nucleotide binding sites in proteolipid protein (PLP), MBP and 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNP). This is consistent with the experimental observations that PLP acts like an ionophore or proton channel when reconstituted into planar lipid bilayers, MBP binds GTP, and CNP catalyzes in vitro the hydrolysis of 2',3'-nucleotides into corresponding 2'-nucleotides. 相似文献
8.
J.K. MOHANA RAO 《Chemical biology & drug design》1987,29(2):276-281
Based on residue characteristic physical parameters, a new scoring matrix, called EMPAR, for amino acid exchanges in proteins was obtained. When comparing protein sequences for detecting homologies, the use of this matrix in place of the Dayhoff log-odds matrix yields results that reflect the topological similarities in the proteins. The use of EMPAR is equivalent to the parametric correlation coefficient approach of Ooi and his colleagues. This matrix correlates at 0.63 with the Dayhoff matrix. 相似文献
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凋亡素基因序列重组及其真核表达载体的构建 总被引:1,自引:0,他引:1
目的:提高凋亡素基因在肿瘤细胞中的表达效率,增强其诱导肿瘤细胞凋亡的生物学活性.方法:通过两次PCR,以pcDNA-VP3质粒为模板,扩增出带Kozak序列(真核核糖体结合位点)的凋亡素基因VP3.将其克隆到真核表达载体pRevTRE的多克隆位点,构建成凋亡素的真核表达载体pRevTRE-VP3,将该质粒分别以限制性内切酶BamHI和XhohI进行酶切鉴定,将初步鉴定显示可能克隆有目的基因的质粒进行测序鉴定.结果:测序结果表明,本研究合成的凋亡素基因与Noteborn报告的凋亡素基因序列一致,同源性为l 00%.在其起始密码子前添加了Ko zak序列的凋亡素基因已成功克隆到真核表达载体pRevTRE.结论:采用两次PCR法可提高表达效率的真核核糖体结合位点添加到凋亡素基因序列起始密码子前端,并构建成凋亡素真核表达载体. 相似文献
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保守氨基酸残基在生物进化过程中具有较强的稳定性,一般不会发生太大的变化;生物信息学认为:氨基酸序列决定蛋白质结构,蛋白质结构决定蛋白质功能。因此,作者基于氨基酸的生化特性、几何特性和动态特性描述了一个新颖的算法去发现蛋白酶家族中的保守氨基酸残基,而保守氨基酸残基将对蛋白质的结构和功能的研究具有重要的意义。 相似文献