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1.
Acoustic analysis of a reading passage was used to identify the abnormal phonatory events associated with adductor spasmodic dysphonia (ADSD) pre- and postinjection of Botulinum Toxin A (Botox). Thirty-one patients (age 22 to 74 years) diagnosed with ADSD were included for study. All patients were new recipients of Botox, and the examination of their voice occurred before and after their initial injection of Botox. Acoustic events were identified from reading samples of the Rainbow Passage produced by each of the patients. These events were examined from sentences containing primarily voiced sound segments. Dependent variables included the number of phonatory breaks, frequency shifts, and aperiodic segments--all variables previously defined by the investigators. Additionally, calculated variables were made of the percentage of time these events occurred relative to the duration of the cumulative voiced segments. A sex- and age-matched control group (+/-2 years) was included for statistical comparison. Results indicated that those with ADSD produced more aberrant acoustic events than the controls. Aperiodicity was the predominant acoustic event produced during the reading, followed by frequency shifts and phonatory breaks. Within the ADSD group, the number of atypical acoustic events decreased following Botox injection. It is important that the occurrence of specific abnormal acoustic events was sufficient to differentiate the disordered speakers from the controls following as well as preceding initial Botox injection, as indicated by discriminant function analysis. This paper complements our previous work using this acoustic analysis method for defining the abnormal events present in the voice of those with ADSD and further suggests that these measures can be used in conjunction with perceptual impressions to differentiate speakers on the basis of initial severity.  相似文献   
2.
Evaluation of an on-line patient exposure meter in neuroradiology   总被引:1,自引:0,他引:1  
  相似文献   
3.
人体液中喷布洛尔及其代谢物的GC/MS分析   总被引:1,自引:0,他引:1  
用气相色谱一质谱联用(GC-MSD)系统分析方法检出了人尿中喷布洛尔的6个羟化代谢物,用Scp-Pak柱提取的方法检出了人血浆中的原型药物。并从分子结构上对此药物的代谢途径进行了研究。尿中提取和血中提取的回收率分别为90.83.%和85.88%,Gc-MSD的检测限为5pg。本方法适用于运动员兴奋剂的系统检查。  相似文献   
4.
New insights into potential mechanisms of ischemic preconditioning   总被引:6,自引:0,他引:6  
  相似文献   
5.
6.
X-linked spinal and bulbar muscular atrophy (SBMA) is caused by a CAG repeat expansion in the first exon of the androgen receptor (AR) gene. Disease-associated alleles (37-66 CAGs) change in length when transmitted from parents to offspring, with a significantly greater tendency to shift size when inherited paternally. As transgenic mice carrying human AR cDNAs with 45 and 66 CAG repeats do not display repeat instability, we attempted to model trinucleotide repeat instability by generating transgenic mice with yeast artificial chromosomes (YACs) carrying AR CAG repeat expansions in their genomic context. Studies of independent lines of AR YAC transgenic mice with CAG 45 alleles reveal intergenerational instability at an overall rate of approximately 10%. We also find that the 45 CAG repeat tracts are significantly more unstable with maternal transmission and as the transmitting mother ages. Of all the CAG/CTG repeat transgenic mice produced to date the AR YAC CAG 45 mice are unstable with the smallest trinucleotide repeat mutations, suggesting that the length threshold for repeat instability in the mouse may be lowered by including the appropriate flanking human DNA sequences. By sequence-tagged site content analysis and long range mapping we determined that one unstable transgenic line has integrated an approximately 70 kb segment of the AR locus due to fragmentation of the AR YAC. Identification of the cis - acting elements that permit CAG tract instability and the trans -acting factors that modulate repeat instability in the AR YAC CAG 45 mice may provide insights into the molecular basis of trinucleotide repeat instability in humans.   相似文献   
7.
Monoclonality of smooth muscle cells in human atherosclerosis.   总被引:8,自引:2,他引:8       下载免费PDF全文
Atherosclerotic plaques contain a large monoclonal population of cells. Monoclonality could arise by somatic mutation, selection of a pre-existing lineage, or expansion of a pre-existing (developmental) clone. To determine the monoclonal cell type in plaque and learn when monoclonality arises, we studied X chromosome inactivation patterns using methylation of the X-linked human androgen receptor gene. Assays based on polymerase chain reaction were performed on samples of known cellular composition, microdissected from histological sections of human arteries. In atherosclerotic vessels, the majority of medial samples (7/11 coronary and 2/3 aortic) showed balanced (paternal and maternal) patterns of X inactivation, indicating polyclonality. In contrast, most samples of plaque smooth muscle cells showed a single pattern of X inactivation (3/4 aortic plaques and 9/11 coronary plaques; P < 0.01 versus media), indicating that plaque smooth muscle cells are monoclonal. Samples of plaque containing inflammatory or endothelial cells showed balanced X inactivation, also demonstrating polyclonality. Multiple plaques from a given patient showed no bias toward one allele, indicating there was no X-linked selection of cells during plaque growth. To determine whether plaques might arise from pre-existing clones (large X inactivation patches), we then studied 10 normal coronaries with diffuse intimal thickening. Six of the ten coronaries showed skewed X inactivation patterns in normal media and intima, suggesting the patch size in normal arteries is surprisingly large. Thus, smooth muscle cells constitute the monoclonal population in atherosclerotic plaques. The finding that normal arteries may have large X inactivation patches raises the possibility that plaque monoclonality may arise by expanding a pre-existing clone of cells rather than generating a new clone by mutation or selection.  相似文献   
8.
In a child with some features of Turner's syndrome, gonosomal mosaicism with an isodicentric nonfluorescent (idic)Y chromosome was detected (mos 45,X/47,X,idic(Y)(q11),idic(Y)(11)/46,X,idic(Y)(q11)). Histopathological examination showed streak gonads with some evidence of ovarian stroma and no sign of gonadoblastoma. Polymerase chain reaction (PCR) analysis in blood lymphocytes and gonadal tissues using primers of seven loci along the Y chromosome, including the sex determined region (SRY), azoospermia factor region (AZF) and the deleted in azoospermia ( DAZ ) gene was positive for all loci tested, confirming the isodicentric character of the Y chromosome and indicating the presence of the AZF region. It is remarkable that the existence of spermatogenesis controlling genes does not play an important role in gonadal development and differentiation in a phenotypic female with some Turner stigmata. The data presented here are briefly discussed with previously-described patients.  相似文献   
9.
Renal transplant (RT) is now a therapy of choice for end stage renal disease (ESRD). The Nephrology Unit, Asvini started functioning in Dec 90 and to date 1298 sittings of hemodialysis have been given to 45 patients. Of these, 35 were in ESRD and 11 patients underwent renal transplantation at this hospital during the period Jan 91 – Dec 93. One patient expired after 18 months of transplantation due to infection. Early experience in screening patients for RT, use of immunosuppression, management of rejection episodes and protocol are presented with special emphasis on its relevance to the Armed Forces.KEY WORDS: Transplantation, Renal Failure, Immunosuppression, Rejection  相似文献   
10.
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