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991.
正常成人嗓音频谱分析 总被引:5,自引:3,他引:5
为探讨不同性别及不同年龄阶段我国正常成人嗓音的声学特征,应用计算机频谱分析技术对145例18~80岁正常人的嗓音进行声学参数检测.结果表明:各年龄段男女基频(F_0),第二、三共振峰(F_2、F_3),频率微扰商(FPQ)以及中、青年男女间振幅微扰商(APQ)有显著性差异,男性振幅微扰商(APQ)随年龄增长而下降,六十岁以后又明显升高,老年男性基频(F_0)明显升高而老年女性基频(F_0)则明显下降.本研究可为临床嗓音的分析评估提供客观的方法和依据. 相似文献
992.
嗓音频谱分析中/a/,/i/音采样的比较 总被引:8,自引:1,他引:8
应用486微型计算机和北京邮电大学通用信号谱分析系统分别对30例青年女性喉病患者和36例健康对照组的/a/、/i/音嗓音信号进行频谱分析,比较其相对信噪比,结论是在频谱分析中用/a/音采样较/i/音更易检出病态嗓音. 相似文献
993.
先天性心脏病重度肺动脉高压性质的综合评价 总被引:8,自引:3,他引:8
目的探讨先天性心脏病(简称先心病)合并重度肺动脉高压患儿器质性肺动脉高压(简称肺高压)的诊断标准。方法37例经手术治疗后早期肺动脉压力降至正常的患儿作为动力性肺高压组;7例经手术治疗后仍持续性肺动脉高压及6例临床诊断为器质性肺高压而未予手术的共13例患儿作为器质性肺高压组,对比两组心导管检查血液动力学指标。结果两组肺血管阻力、肺小动脉楔压、肺循环血流量与体循环血流量之比(Qp/Qs)及降主动脉血氧饱和度(SaO2)差异均有显著意义,如按年龄大于2岁、肺动脉阻力>72kPa·s-1·L-1(9Wood单位)、肺小动脉楔压≤1.6kPa(12mmHg)、Qp/Qs<2和动脉血氧饱和度<0.90作为临床诊断器质性肺高压的指标,则本组动力性肺高压组仅有5.4%的患儿符合上述指标3项或3项以上,而器质性肺高压组所有病例均符合上述指标3项或3项以上。结论先心病合并重度肺动脉高压存在上述5项指标中3项或3项以上,高度提示患儿存在器质性肺动脉高压 相似文献
994.
三氧化二砷对神经母细胞瘤细胞增殖的影响 总被引:13,自引:1,他引:13
目的探讨三氧化二砷(As2O3)对儿童神经母细胞瘤有无潜在的治疗价值及伍用细胞因子有无增强疗效的作用。方法应用四甲基偶氮唑蓝法于体外观察As2O3对神经母细胞瘤细胞株SJ-N-SH增殖的影响;并观察As2O3伍用重组人γ-干扰素、肿瘤坏死因子、白细胞介素4、6、10后的情况。结果0.5~4μmol/L的三氧化二砷明显抑制SJ-N-SH细胞的增殖,As2O3伍用γ-干扰素、白细胞介素4可明显增强As2O3对SJ-N-SH细胞增殖的抑制,而其他几种细胞因子无明显作用。结论As2O3为治疗神经母细胞瘤的有效药物,联合应用合适的细胞因子可增强As2O3的疗效。 相似文献
995.
996.
Recent molecular cytogenetic studies have elucidated the origin and nature of extra structurally abnormal chromosomes (ESACs)
or small supernumerary chromosomes, which are often associated with developmental delay and malformations. We studied the
prevalence of inv dup(15) in a nationwide screening programme for mentally retarded children in Taiwan and tried to correlate
the genotype and phenotype in those patients. Fluorescence in situ hybridization (FISH) analysis using D15Z, D15Z1, and the
cosmids from the Prader-Willi/Angelman syndrome chromosome region (PW/ASCR) was performed on 54 patients (0.45%) with ESACs
from 11893 probands within a 5-year period. Of them, inv dup(15) was confirmed in 25 children (46.3%) by FISH analysis. The
PW/ASCR probes were used to clarify the size and DNA composition of the markers. Patients with inv dup(15) chromosomes, containing
only the heterochromatin or little euchromatin of the proximal 15q (i.e., pter→q11:q11→pter) may have a rather mild or nearly
normal phenotype (group 1). Only one patient had some features suggestive of Angelman syndrome, but was considered to be a
result of deleted (15)(q12) in the chromosome 15 homologue. Additional copies within D15S11 through GABRB3 (15q11.2-13) resulted
in an abnormal phenotype which involved mental and developmental delay but was different from the classical phenotype of PW/AS
(groups 2, 3). Signs of autistic behavior did occur in each group. FISH combined with microsatellite analyses showed that
the marker was often of maternal origin in de novo cases (n = 12, 86%), or inherited from the mother in only one familial case. Down-inv dup(15) was mentioned in two cases. Unusual
features including diaphragmatic eventration, hyperlaxity of joints, arachnodactyly, brain atrophy, epilepsy (particularly
infantile spasm), ataxia, genital abnormalities, and cleft lip/palate were noted in those patients. This observation expands
the range of phenotypic expression associated with this relatively common ESAC.
Conclusion Marked phenotypic diversities exist in children with inv dup(15), dependent upon the size or genetic composition of the markers,
degree of mosaicism, parental origin and familial occurrence or not. Patients with a larger inv dup(15) marker chromosome
including the PW/ASCR may have a higher risk of abnormalities, but not the typical Prade-Willi/Angelman syndrome phenotype.
Received: 11 February 1997 and in revised form: 20 May 1997 / Accepted: 20 May 1997 相似文献
997.
目的探讨涉颅良性鼻腔、鼻窦肿瘤的手术治疗方法。方法报道6例鼻腔、鼻窦良性肿瘤侵及颅底的病例,其中骨化纤维瘤3例,骨瘤1例,骨软骨瘤1例,骨巨细胞瘤(I~I级)1例,均采用1侧上颌骨掀翻复位术及颅面联合进路手术切除肿瘤,全部切除肿瘤4例,近次全切除2例。结果无手术并发症,术后随访2~3年,5例无异常,1例骨化纤维瘤术后2年复发。结论上颌骨掀翻术是一种较好的治疗涉颅良性鼻腔、鼻窦肿瘤的手术方法。 相似文献
998.
Evaluation of the effectiveness of preoperative embolization in surgery for nasopharyngeal angiofibroma 总被引:4,自引:0,他引:4
We retrospectively analyzed the clinical data of 21 patients (22 procedures) with histologically proven nasopharyngeal angiofibromas.
Eleven patients underwent preoperative intra-arterial digital subtraction angiography (IADSA) and embolization with Gelfoam.
Embolization reduced the intraoperative blood loss from an average of 1136 ml in the non-embolized patients to 677 ml in the
embolized cases (P < 0.05) and transfusions from an average of 836 ml to 400 ml (P < 0.01). Results again show that preoperative embolization is effective in reducing intraoperative blood loss.
Received: 10 May 1997 / Accepted: 21 October 1997 相似文献
999.
Objectives: Tumor suppressor gene mutations in both p53 and PTEN/MMAC1 genomic DNA have been detected in many types of cancer. The purpose of this study was to investigate the presence and importance of PTEN/MMAC1 mutations in squamous cell carcinomas. Methods: Exons of each gene were amplified after polymerase chain reaction (PCR) using genomic DNA derived from cell lines of squamous cell carcinoma of the head and neck (SCCHN) and snap-frozen biopsy specimens from primary established head and neck tumors. The amplified and purified DNA was then sequenced directly. Result: As anticipated, point mutations of the p53 gene were found in 80% of cell lines examined. A single base mutation in codon 151 was found in six of 10 cell lines studied. PTEN/MMAC1 gene mutations were found in neither the cell lines tested nor the tumor biopsy samples. Conclusion: This study, as well as a large volume of data, confirms that mutations of the p53 gene are frequent events in head and neck cancer cell lines. Although PTEN/MMAC1 gene mutations have been found in a variety of carcinomas, this gene was not found to be mutated in SCCHN cell lines or in primary squamous cell carcinomas of the head and neck. This information is useful for further studies of mutations in these cell lines. Laryngoscope, 108:1553–1556, 1998 相似文献
1000.
Guo RJ; Wang Y; Kaneko E; Wang DY; Arai H; Hanai H; Takenoshita S; Hagiwara K; Harris CC; Sugimura H 《Carcinogenesis》1998,19(9):1539-1544
Mutations in the transforming growth factor beta type II receptor
(TGFbetaRII) gene have been detected in several human cancer types
exhibiting microsatellite instability. Using intron primers previously
reported for examination of the entire coding region of the TGFbetaRII
gene, 29 sporadic gastric cancers were screened with non-radioactive single
strand conformation polymorphism and subsequent DNA sequencing analysis.
Mutations of the TGFbetaRII gene were detected in three out of 29 tumors
(10%). Two cases showed deletions in a polyadenine tract in both alleles
and was positively associated with replication error. One case had an
insertion of GA dinucleotide sequence in one allele. Mutations of the
TGFbetaRII gene were restricted to exon 3 and other coding regions were not
affected. Loss of heterozygosity was detected by analyzing a polymorphic
site in intron 2. Three out of nine (33%) informative cases, which were all
of intestinal type and advanced cases, showed loss of heterozygosity but
neither TGFbetaRII mutation nor replication error was found in these cases.
Immunoreactivity of TGFbetaRII in tumor tissues was reduced to a different
extent in the gastric cancer with genetically abnormal transforming growth
factor. Although the numbers studied are small, homozygous (A)10 deletion
or loss of heterozygosity of TGFbetaRII is involved in tumorigenesis and
progression of at least some part of sporadic gastric cancer.
相似文献