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1.
Symptomatic HIV infection of the CNS in a patient without clinical evidence of immune deficiency 总被引:1,自引:0,他引:1
A Beckett P Summergrad T Manschreck H Vitagliano M Henderson M L Buttolph M Jenike 《The American journal of psychiatry》1987,144(10):1342-1344
Major depression with psychotic features, dementia, and focal neurologic abnormalities appeared in a Haitian man without AIDS or other syndromes of immune compromise. Neurologic evaluation, including brain biopsy, was nondiagnostic, but CSF culture revealed human immunodeficiency virus (HIV). 相似文献
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CG Teo 《Oral diseases》2002,8(S2):88-90
Oral hairy leukoplakia (OHL) and Kaposi's sarcoma (KS) are commonly encountered in the HIV-infected patient. A unique feature of OHL is non-cytolytic high level of replication of Epstein–Barr virus (EBV) in the glossal epithelium. The expression of viral-encoded anti-apoptotic proteins concomitant to replicative proteins probably underlies this phenomenon. The question of whether OHL arises from activation of EBV latent in the tongue, or from superinfection by endogenous EBV shed via non-glossal sites or by exogenous EBV remains unresolved. Human herpesvirus 8 (HHV8) is now seen as necessary but not sufficient cause of KS. Expression of HHV8-encoded oncogenic proteins in endothelial cells probably explains the aberrant proliferation of these cells in KS lesions. Studies into why KS is so commonly observed at the palate in HIV-infected patients may provide important clues to its pathogenesis. 相似文献
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W S Beckett M B Russi A D Haber R M Rivkin J R Sullivan Z Tameroglu V Mohsenin B P Leaderer 《Environmental health perspectives》1995,103(4):372-375
Nitrous acid, a component of photochemical smog and a common indoor air pollutant, may reach levels of 100 ppb where gas stoves and unvented portable kerosene heaters are used. Nitrous acid is a primary product of combustion and may also be a secondary product by reaction of nitrogen dioxide with water. Because the usual assays for nitrogen dioxide measure several oxides of nitrogen (including nitrous acid) together, previous studies of indoor nitrogen dioxide may have included exposure to and health effects of nitrous acid. To assess the respiratory effects of nitrous acid exposure alone, we carried out a double-blinded crossover chamber exposure study with 11 mildly asthmatic adult subjects. Each underwent 3-hr exposures to 650 ppb nitrous acid and to filtered room air with three 20-min periods of moderate cycle exercise. Symptoms, respiratory parameters during exercise, and spirometry after exercise were measured. A statistically significant decrease in forced vital capacity was seen on days when subjects were exposed to nitrous acid. This effect was most marked at 25 min and 85 min after exposure began. Aggregate respiratory and mucous membrane symptoms were also significantly higher with nitrous acid. We conclude that this concentration and duration of exposure to nitrous acid alters lung mechanics slightly, does not induce significant airflow obstruction, and produces mild irritant symptoms in asthmatics. 相似文献
9.
Incidence of Hyperpronation in the ACL Injured Knee: A Clinical Perspective 总被引:2,自引:1,他引:1
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Assessing abnormal biomechanics when treating various lower extremity pathologies provides the athlete with comprehensive management and promotes injury prevention. However, there have been few previous investigations of abnormal biomechanical forces on ligamentous pathologies of the knee. During this clinical study we investigated the incidence of hyperpronation in subjects who have had an anterior cruciate ligament (ACL) injury. Fifty subjects with a past medical history of ACL rupture and 50 subjects without a history of lower extremity pathology participated in our study. Hyperpronation of the foot and ankle complex was measured with the navicular drop test. The ACL injured subjects had greater navicular drop test scores than noninjured subjects. This suggests that hyperpronation of the foot and ankle complex may increase the risk of injury to the ACL. There is a need for further investigation into possible pre-loading stresses on knee ligaments. 相似文献
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The property of aerobic glycolysis commonly possessed by malignant cells points to a weakness in oxidative metabolism which has been equated in some tumours with partial uncoupling of oxidative phosphorylation. The suggestions are made, first, that this endogenous defect may account for spontaneous cell death
, and, second, that its accentuation would inflict extensive tumour injury upon sensitive neoplasms. Certain drugs not in current use for the treatment of malignant disease are known to be able to interfere selectively with energy metabolism in sensitive tumours to such an extent that widespread necrotisation ensues. The drugs activate an endogenous destructive mechanism that appears to require oxygen. Liminal therapy, the maintenance of continuous destructive pressure on sensitive growths in such a manner that maximal anti-tumour activity in terms of interference with energy production is not achieved at any one time, and under conditions in which the oxygen supply is only partly depleted, is put forward as a possible means of achieving complete and selective tumour destruction
. 相似文献