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Two unique characteristics of vocal fry register are the occurrence of multiple opening and closing phases occurring within one vibratory cycle and a similar vocal fundamental frequency (F0) between women and men. The present study tested the hypothesis that significant differences in glottal cycle symmetry exist between women and men during modal phonation, with no significant differences during vocal fry phonation. Consistent with previous studies of modal phonation, it was also hypothesized that a vowel effect would be apparent during vocal fry phonation. Five women and 5 men sustained modal and vocal fry phonations in four vowel contexts (/a, ae, u, i/). Vocal F0, duration of opening and closing phase, and contact symmetry (speed quotient) were derived from electroglottographic (EGG) waveforms. Both female and male speakers demonstrated significantly higher SQ values in vocal fry register than in their modal register, indicating a longer opening-phase duration per glottal cycle. Women demonstrated a significantly greater increase in SQ during vocal fry phonations than men, indicating greater asymmetry between opening and closing durations. The results confirmed that gender differences in vocal fold contact behavior not only exist during modal register but also during vocal fry register. No vowel effects on vocal fold contact behavior as inferred using the SQ measure were found for either modal or vocal fry registers. Possible contributing factors to multiple opening and closing phases occurring within a vibratory cycle are discussed.  相似文献   
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We previously described the use of extended polymerase chain reaction (PCR) to amplify contiguous 9.2-kilobase (kb) single-long terminal repeat (LTR) proviral sequences from HIV-1 genetic subtypes A through G. We now extend these findings by describing a novel vector system to recover infectious molecular clones from long PCR amplicons. Directional ligation of 9.2-kb proviral amplicons into a recovery vector reconstitutes missing LTR sequences, providing candidate molecular clones for infectivity screening. We show that a previously characterized infectious molecular clone of HIV-1 retains its biological properties upon recovery with this strategy. Three additional infectious molecular clones generated, from primary isolates of subtype B (HIV-1(WR27)) and circulating recombinant form 01_AE (subtype E) (HIV-1(CM235)) by subtype-specific LTR reconstitution, displayed biological properties reflecting their cognate parental isolates. This represents the first report of infectious molecular clones from circulating recombinant form 01_AE (subtype E).  相似文献   
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Postirradiation atrophic changes of bone and related complications   总被引:2,自引:0,他引:2  
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A M Bajart  R M Robb 《Ophthalmology》1979,86(8):1401-1406
Three patients are reported in whom paralysis of accommodation and mydriasis (internal ophthalmoplegia) developed following inferior oblique myectomy. In all three patients, accommodation eventually returned to normal; in two, mild anisocoria persisted; in one patient, pupillotonia was noted after 2 1/2 years. The mechanism of this previously unreported surgical complication is thought to be excessive stretching of the nerve to the inferior oblique muscle with secondary trauma to the ciliary ganglion.  相似文献   
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Background. Maspin is both overexpressed in tumors and inflammation, implicating a possible role in bridging inflammation and neoplasia. Idiopathic inflammatory bowel disease (IBD) and IBD-associated dysplasias and carcinomas represent a prototype for studying the relationship between chronic inflammatory states and neoplasia. Aim of Study. To investigate expression of maspin in IBD and IBD-associated dysplasia and colorectal carcinoma. Methods. Immunohistochemical labeling of maspin was examined using tissue microarrays constructed from archival biopsy and resection tissue from 90 patients with 125 histologically defined lesions including 30 with inactive chronic IBD, 51 with active chronic IBD, 4 IBD-associated foci with epithelial changes indefinite for dysplasia (IFD), 7 with IBD-associated low-grade epithelial dysplasia (LGD), 8 with IBD-associated high grade epithelial dysplasia (HGD), and 25 with IBD-associated invasive colorectal adenocarcinomas. Results. Maspin was expressed in 47/51 (92%) active chronic IBD lesions, which was significantly higher than both inactive chronic IBD (13/30, 43%) and normal mucosa (1 of 9, 11%) (p<0.01); in particular, the diffuse pattern of maspin expression was significantly higher in active IBD (41/51, 80%), compared with inactive IBD (5/30, 17%) and normal mucosa (0%) (p<0.01). In the multistage progression model of colitis-associated neoplasia, aberrant labeling was observed at the earliest stages, with 3/4 (75%) IFD foci, 6/7 (86%) LGD, and 8/8 (100%) HGD specimens expressing maspin, virtually always in a diffuse pattern. Expectedly, 22/25 (88%) of invasive IBD-associated cancers overexpressed maspin, including 21 with diffuse labeling. Conclusions. Maspin is significantly overexpressed in both active IBD and colitis-associated dysplasia compared to either inactive IBD or normal colonic mucosa, suggesting a potential role in disease “flare” as well as neoplastic progression. Targeting maspin for control of disease activity and cancer prophylaxis may be a promising novel therapeutic strategy for IBD.  相似文献   
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