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This survey among 1 000 french male homosexuals and bisexuals (July-August 1985) shows the reactions to AIDS in the still largest risk group. The survey reveals the diversity of social and sexual lifestyles. Gays perceive AIDS as a health threat, but also as a social threat eventually leading to discrimination. Ambivalence also prevails in their relationships with medical authorities. This survey allows to draw some conclusions concerning preventive strategies in the gay community.  相似文献   
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Glazer  HS; Gutierrez  FR; Levitt  RG; Lee  JK; Murphy  WA 《Radiology》1985,157(1):149-155
Thirty-three patients with a variety of disorders of the thoracic aorta (aneurysm, dissection, Marfan syndrome, coarctation/pseudocoarctation, L-transposition, and Takayasu disease) were evaluated with magnetic resonance (MR) imaging. MR imaging delineated the presence and extent of thoracic aortic aneurysms and showed the relationship of the aneurysm to arch vessels; it also demonstrated intimal flaps and individual lumina in types A and B aortic dissection. Dilation of the ascending aorta in Marfan syndrome and focal narrowing of the aorta in coarctation were well visualized. The anteroposterior and side-to-side relationships of the aorta and pulmonary artery in L-transposition were demonstrated, as were aortic wall thickening and branch vessel narrowing in Takayasu arteritis. Initial experience suggests that MR imaging may provide a noninvasive method for evaluating thoracic aortic disease. Limitations include inferior spatial resolution, occasional difficulty in imaging the entire region of interest in one section, lack of signal from calcifications, and inability to monitor critically ill patients.  相似文献   
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Purpose: This study assessed the effect of 6 months of aging in water on surface roughness and surface/subsurface hardness of two microhybrid resin composites. Materials and Methods: Filtek Z250 and Charisma were tested. Cylindrical specimens were obtained and stored in distilled water for 24 hours or 6 months, at 37°C. For Knoop hardness evaluation, the specimens were transversely wet‐flattened, and indentations were made on surface and subsurface layers. Data were submitted to three‐way ANOVA and Tukey's test (α≤ 0.05). Surface roughness baseline measurements were made at 24 hours and repeated after 6 months of storage. Data were submitted to repeated measures ANOVA and Tukey's test (α≤ 0.05). Results: Surface hardness (KHN, kg/mm2) means (± standard deviation) ranged from 55 ± 1 to 49 ± 4 for Z250 and from 50 ± 2 to 41 ± 3 for Charisma, at 24 hours and 6 months, respectively. Subsurface means ranged from 58 ± 2 to 61 ± 3 for Z250 and from 50 ± 1 to 54 ± 2 for Charisma, at 24 hours and 6 months. For both composites, the aged specimens presented significantly softer surfaces (p < 0.01). For the subsurface hardness, alteration after storage was detected only for Charisma, which presented a significant rise in hardness (p < 0.01). Z250 presented significantly harder surface and subsurface layers in comparison with Charisma. Surface roughness (Ra, μm) means ranged from 0.07 ± 0.00 to 0.07 ± 0.01 for Z250 and from 0.06 ± 0.01 to 0.07 ± 0.01 for Charisma, at 24 hours and 6 months, respectively. For both composites, no significant roughness alteration was detected during the study (p= 0.386). Conclusions: The 6‐month period of storage in water presented a significant softening effect on the surfaces of the composites, although no significant deleterious alteration was detected for the subsurface hardness. In addition, the storage period had no significant effect on the surface roughness of the materials.  相似文献   
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Clinical Oral Investigations - This study aimed to investigate the presence of BRAF V600E mutation in mandible ameloblastomas by correlating clinical and imaging data on the cases studied....  相似文献   
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