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61.
Oral hairy leukoplakia: diagnosis and management   总被引:3,自引:0,他引:3  
Oral hairy leukoplakia (HL) is a remarkable lesion associated with Epstein-Barr virus (EBV) found in persons infected with the human immunodeficiency virus. The clinical and histologic features of HL are characteristic and distinctive. However, none of these features are entirely specific for HL, and we consider that the presence of EBV is required for diagnosis in questionable cases. EBV can be demonstrated by means of electron microscopy, immunocytochemistry, or molecular biologic techniques. Therapy directed toward the HL lesion is sometimes indicated; acyclovir is the current drug of preference in such cases.  相似文献   
62.
We examined 142 biopsy specimens of smokeless tobacco-associated oral mucosal lesions from 133 professional baseball players. Four types of epithelial change were observed in the specimens: hyperparakeratosis, hyperorthokeratosis, pale surface staining, and basal cell hyperplasia. These types of epithelial change were associated with the type of smokeless tobacco used (snuff or chewing tobacco) but not with the duration (years) or amount (hours per day) of use. The thickness of hyperkeratosis in a specimen correlated directly with the amount of smokeless tobacco use. The use of snuff was more frequently associated with development of oral mucosal lesions than was the use of chewing tobacco, and snuff appeared to cause a greater variety and severity of epithelial change than did chewing tobacco.  相似文献   
63.
In 4.4% of human immunodeficiency virus-associated non-Hodgkin's lymphoma the presenting lesion is seen in the mouth. Often the lesion may clinically resemble a less sinister process, and a definitive diagnosis of lymphoma may be delayed. We describe three unusual cases of non-Hodgkin's lymphoma, appearing intraorally in association with other oral lesions, in HIV-positive homosexual men. The three patients reported here were all diagnosed as having diffuse, large-cell malignant non-Hodgkin's lymphoma. We performed Epstein-Barr virus DNA in-situ hybridization on our cases and Epstein-Barr virus DNA sequences were not seen. We review the pertinent literature and stress the importance of including non-Hodgkin's lymphoma in the differential diagnosis of oral lesions in patients at risk of HIV infection.  相似文献   
64.
This study was conducted to characterize the recurrent aphthous ulcers (RAU) found in association with human immunodeficiency virus (HIV) infection, to examine evidence for increased severity of the ulcers with HIV disease, and to determine whether increased severity is associated with abnormalities of peripheral blood lymphocyte subsets. Seventy-five HIV-seropositive patients with RAU were followed for up to 2 years, and lymphocyte subsets were analyzed in 42. Minor, herpetiform, and major ulcer types were seen, but unexpectedly, 66% of the patients had the usually uncommon herpetiform and major types. These types were temporally associated with symptomatic HIV disease. Patients with major RAU were significantly more immunosuppressed than those with minor or herpetiform RAU in that they had fewer CD4 and CD8 lymphocytes (p less than 0.05). The lesion of RAU is considered to represent a local breakdown in immunoregulation. The systemic immune imbalance seen with HIV disease may amplify the local defect and lead to more severe ulcers.  相似文献   
65.
66.

Purpose  

Post-herniation abdominal wall repair can be performed with synthetic or biologic meshes. Synthetics have been associated with complications, so biologics are promising alternatives. The methods used to decellularize biological matrices may affect the extracellular components. This study evaluated the post-implantation biological response of two allogenic acellular dermal matrices (ADMs) in a hernia model.  相似文献   
67.
68.
Purpose: To assess the efficacy, safety, and tolerability of the investigational drug carisbamate as adjunctive treatment for partial‐onset seizures (POS). Methods: Two identical, randomized, placebo‐controlled, double‐blind studies were conducted in adults with POS uncontrolled for ≥1 year. Therapy‐refractory epilepsy patients (≥16 years) remained on stable doses of prescribed antiepileptic drugs (≤2) for an 8‐week prospective baseline phase and were then randomized (1:1:1) to carisbamate 200 mg/day, carisbamate 400 mg/day, or placebo, for a 12‐week double‐blind phase. Primary efficacy end points were percent reduction in seizure frequency and responder rate (patients with ≥50% reduction in POS frequency) during the double‐blind phase compared with the prospective baseline phase. Results: Of the 565 patients randomized in study 1, 93% completed the study; of the 562 randomized in study 2, 94% completed the study. Patient characteristics were similar across both studies and treatment arms: mean age, 35 years (study 1, range 16–75 years) and 36 years (study 2, range 16–74 years); approximately 50% were men. Treatment with carisbamate 400 mg/day resulted in significant improvement (p < 0.01) in both efficacy measures compared with placebo in study 1 but not in study 2. Carisbamate 200 mg/day did not differ statistically from placebo in either study. Among the most common treatment‐emergent adverse events (≥5% in any group), those with an incidence exceeding placebo (≥3%) were dizziness (400 mg/day group) and somnolence. Conclusions: Carisbamate 400 mg/day was effective in patients with refractory partial‐onset seizures in one of these global studies. More than 200 mg/day of carisbamate is required for efficacy. Carisbamate was well‐tolerated in both studies.  相似文献   
69.
The Oral HIV/AIDS Research Alliance (OHARA) is part of the AIDS Clinical Trials Group (ACTG), the largest HIV clinical trials organization in the world. Its main objective is to investigate oral complications associated with HIV/AIDS as the epidemic is evolving, in particular, the effects of antiretrovirals on oral mucosal lesion development and associated fungal and viral pathogens. The OHARA infrastructure comprises: the Epidemiologic Research Unit (at the University of California San Francisco), the Medical Mycology Unit (at Case Western Reserve University) and the Virology/Specimen Banking Unit (at the University of North Carolina). The team includes dentists, physicians, virologists, mycologists, immunologists, epidemiologists and statisticians. Observational studies and clinical trials are being implemented at ACTG-affiliated sites in the US and resource-poor countries. Many studies have shared end-points, which include oral diseases known to be associated with HIV/AIDS measured by trained and calibrated ACTG study nurses. In preparation for future protocols, we have updated existing diagnostic criteria of the oral manifestations of HIV published in 1992 and 1993. The proposed case definitions are designed to be used in large-scale epidemiologic studies and clinical trials, in both US and resource-poor settings, where diagnoses may be made by non-dental healthcare providers. The objective of this article is to present updated case definitions for HIV-related oral diseases that will be used to measure standardized clinical end-points in OHARA studies, and that can be used by any investigator outside of OHARA/ACTG conducting clinical research that pertains to these end-points.  相似文献   
70.
The short-term distribution kinetics of exogenous surfactant distribution after intratracheal instillation was investigated in surfactant-deficient neonatal piglets during assisted conventional mechanical ventilation and by high-frequency jet ventilation using exogenous calf lung surfactant extract (CLSE) labeled with 99mTc. Surfactant deficiency was induced by repeated bronchoalveolar lavage in piglets (1.2 +/- 0.4 kg, 1.4 +/- 0.7 d of age), and the short-term distribution kinetics of instilled, labeled CLSE were followed by gamma radioscintigraphy. Animals ventilated by either conventional mechanical ventilation or high-frequency jet ventilation showed similar improvement in arterial/alveolar oxygen ratios after surfactant replacement therapy (0.47 +/- 0.03 prelavage, 0.09 +/- 0.01 postlavage, 0.36 +/- 0.06 postsurfactant). This correlated directly with dynamic radioscintigraphic results showing that instilled CLSE began to distribute to the lungs within 5 s, and was present in substantial amounts in standardized symmetrical lung fields (central, right, and left; upper and lower) within 20 s of tracheal instillation. Subsequent measurements over 30 min showed continued presence of radiolabeled CLSE in all five areas of the lung, with no significant difference between conventional mechanical ventilation and high-frequency jet ventilation animals. Static (5-min) analyses at the end of this period showed that surfactant had distributed relatively symmetrically with 30% of the CLSE located in central regions, 40% in the upper lobes, and 30% in the lower lobes. In contrast, piglets receiving 99mTc in saline showed nonuniform distribution with multiple filling defects noted throughout the lungs. The rapid kinetics and ventilation independence of CLSE distribution suggest that surfactant spreading phenomena after tracheal instillation may facilitate the delivery of exogenous surfactant into aerated lungs in therapeutic applications.  相似文献   
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