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1.
There are many potential sources of variability in speech production, particularly in individuals with dysarthria. The degree and time course of stabilization of the speech production system during recovery from a neurological insult is not constant across individuals. Another source of variability in speech production is speaking rate. Although individuals with no neurological impairments typically show increased variability at reduced speaking rates, this phenomenon has not been explored extensively in individuals with dysarthria. Because rate control strategies are commonly used in dysarthria treatment, it is of clinical importance to know if individuals with dysarthria produce less variable speech with rate reduction. Six individuals with mild dysarthria, 6 with moderate-to-severe dysarthria, and 6 matched normal controls repeated an utterance in four speaking rate conditions: habitual, fast, breaks between words, and stretched. Data were analyzed using the spatiotemporal index (STI), a composite measure of spatial and temporal variability across token repetitions. The normal controls consistently demonstrated the least variability, regardless of rate condition. Both groups with dysarthria were the least variable in the stretched condition and the most variable in the fast condition. The STI values of the group with moderate-to-severe dysarthria were significantly different from both the individuals with mild dysarthria and the normal controls. There were no significant differences between the group with mild dysarthria and the normal controls. In general, slowing the speaking rate in individuals with dysarthria reduces spatiotemporal variability; however, the effect of reduced spatiotemporal variability on intelligibility requires further investigation.  相似文献   
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BACKGROUND: Nitric oxide (NO) plays a key role in wound repair and S-nitrosothiols like S-nitrosoglutathione (GSNO) are well known NO donors. METHODS: Animals were separated in two groups and submitted to excisional wounds on the dorsal surface at the first day. GSNO (100 microm)-containing hydrogels were topically applied on the wound bed in the GSNO group, daily, during the first 4 days. Control group was topically treated with hydrogel without GSNO for the same period. Wound contraction and re-epithelialization were measured. Animals were sacrificed 21 days after wounding. Samples of lesion and normal tissue were formalin-fixed, paraffin embedded for histological analysis. RESULTS: Wound contraction, measured 14 and 21 days after wounding, was greater in the GSNO group than in the control group (P<0.05 for both). The re-epithelialized wound area, measured 14 days after wounding, was higher in the GSNO group than in the control group (P<0.05). A higher amount of inflammatory cells was observed in superficial and deep areas of the granulation tissue of the control group compared to the GSNO group. Twenty-one days after wounding, thin red-yellow collagen fibers arranged perpendicularly to the surface were found in the granulation tissue of the control group, whereas in the GSNO-treated group collagen fibers were thicker and arranged parallel to the surface. Increased number of mast cells was observed in the GSNO group compared with that in the control group. Vascularization and myofibroblast distribution were similar in both groups. CONCLUSION: Topical application of GSNO-containing hydrogel during the early phases of rat cutaneous wound repair accelerates wound closure and re-epithelialization and affects granulation tissue organization.  相似文献   
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Two final year dental students spent an elective period in the HIV clinic of the Dental Hospital of the Freie University of Berlin. The oral manifestations and management of 50 HIV patients were observed.  相似文献   
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Biliary tract obstruction in a 30-year-old man was found to be caused by a malignant melanoma in the common bile duct. Melanin pigment was demonstrated by immunohistochemistry and electron microscopy. Extensive search for a primary malignant melanoma elsewhere was unsuccessful. No pigmented lesions had been removed previously. There were junctional changes in the mucosa of the common bile duct close to the tumor. The malignant melanoma in the common bile duct therefore is considered to be primary. Only one other case of primary malignant melanoma in the common bile duct has been described in the literature, whereas metastases to the major bile ducts in one autopsy study of malignant melanoma in the more common locations were found with a frequency of 6 per cent.  相似文献   
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BACKGROUND: Boys and young men with hemophilia treated with factor infusions before 1985 had a substantial risk of acquiring the human immunodeficiency virus (HIV) and the acquired immunodeficiency syndrome. This study was designed to assess the effects of HIV and hemophilia per se on neurological function in a large cohort of subjects with hemophilia, and to investigate the relationships between neurological disease and death during follow-up. METHODS: Three hundred thirty-three boys and young men (207 HIV seropositive and 126 HIV seronegative) were evaluated longitudinally in a multicenter, multidisciplinary study. Neurological history and examination were conducted at baseline and annually for 4 years. The relationship between neurological variables, HIV serostatus, CD4+ cell counts, and vital status at the conclusion of the study was examined using logistic regression models. RESULTS: The risks of nonhemophilia-associated muscle atrophy, behavior change, and gait disturbance increased with time in immune compromised HIV-seropositive subjects compared with HIV seronegative or immunologically stable HIV-seropositive subjects. The risk of behavior change in immune compromised HIV-seropositive hemophiliacs, for example, rose to 60% by year 4 versus 10% to 17% for the other study groups. Forty-five subjects (13.5%), all of whom were HIV seropositive, died by year 4. Subjects who died had had increased risks of hyperreflexia, nonhemophilia-associated muscle atrophy, and behavior change. CONCLUSIONS: These results indicate that immune compromised, HIV-seropositive hemophiliacs have high rates of neurological abnormalities over time and that neurological abnormalities were common among subjects who later died. By contrast, immunologically stable HIV-seropositive subjects did not differ from the HIV-seronegative participants. Hemophilia per se was associated with progressive abnormalities of gait, coordination, and motor function.  相似文献   
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