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排序方式: 共有1710条查询结果,搜索用时 15 毫秒
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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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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
6.
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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![点击此处可从《Journal of Athletic Training》网站下载免费的PDF全文](/ch/ext_images/free.gif)
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
7.
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
8.
Susceptibility of cyclooxygenase-2-deficient mice to pulmonary fibrogenesis 总被引:6,自引:0,他引:6
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![点击此处可从《The American journal of pathology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Bonner JC Rice AB Ingram JL Moomaw CR Nyska A Bradbury A Sessoms AR Chulada PC Morgan DL Zeldin DC Langenbach R 《The American journal of pathology》2002,161(2):459-470
The cyclooxygenase (COX)-2 enzyme has been implicated as an important mediator of pulmonary fibrosis. In this study, the lung fibrotic responses were investigated in COX-1 or COX-2-deficient (-/-) mice following vanadium pentoxide (V(2)O(5)) exposure. Lung histology was normal in saline-instilled wild-type and COX-deficient mice. COX-2(-/-), but not COX-1(-/-) or wild-type mice, exhibited severe inflammatory responses by 3 days following V(2)O(5) exposure and developed pulmonary fibrosis 2 weeks post-V(2)O(5) exposure. Western blot analysis and immunohistochemistry showed that COX-1 protein was present in type 2 epithelial cells, bronchial epithelial cells, and airway smooth muscle cells of saline or V(2)O(5)-exposed wild-type and COX-2(-/-) mice. COX-2 protein was present in Clara cells of wild-type and COX-1(-/-) terminal bronchioles and was strongly induced 24 hours after V(2)O(5) exposure. Prostaglandin (PG) E(2) levels in the bronchoalveolar lavage (BAL) fluid from wild-type and COX-1(-/-) mice were significantly up-regulated by V(2)O(5) exposure within 24 hours, whereas PGE(2) was not up-regulated in COX-2(-/-) BAL fluid. Tumor necrosis factor-alpha was elevated in the BAL fluid from all genotypes after V(2)O(5) exposure, but was significantly and chronically elevated in the BAL fluid from COX-2(-/-) mice above wild-type or COX-1(-/-) mice. These findings indicate that the COX-2 enzyme is protective against pulmonary fibrogenesis, and we suggest that COX-2 generation of PGE(2) is an important factor in resolving inflammation. 相似文献
9.
Empiric analysis of the interactions involved in the formation of Fc receptor rosettes 总被引:1,自引:0,他引:1
R C Beckett A D Bankhurst D E Van Epps R C Williams 《International archives of allergy and applied immunology》1978,56(1):65-72
Erythrocytes coated with IgG were used in forming rosettes with lymphocytes and polymorphonuclear leukocytes to investigate Fc receptors. The density of the IgG-Fc coating on erythrocytes predictable influenced the number of rosettes formed with leukocytes. This relationship could be empirically described by application of the Hill equation derived from studies of molecular interactions in other biologic systems. The approximate Hill coefficient for Fc receptors was 2.4. These findings suggest at least two possible models for membrane Fc receptor function. 相似文献
10.
Liver function was assessed in 38 Edinburgh haemophiliacs. Results before the introduction of NHS intermediate factor VIII concentrate from 1974 onwards were compared with values in 1979. Measurements of serum bile salts in 16 patients as well as conventional liver function tests gave useful evidence of deranged liver function. Deterioration over the five-year follow-up period was seen only in patients on home treatment using large amounts of factor VIII concentrate, and there was no association between cryoprecipitate usage and derangement of liver function. 相似文献