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1.
BACKGROUND: A subgroup of children with obsessive-compulsive and tic disorders are proposed to have an infectious trigger. The purpose of this study was to investigate the relationship between group A streptococcal titers and symptom fluctuations in children with a clinical course resembling that described for pediatric autoimmune neuropsychiatric disorders associated with streptococcus. METHODS: Twenty-five children with obsessive-compulsive disorder and/or tic disorder were evaluated for neuropsychiatric severity and group A streptococcal antibody titers (streptolysin O, deoxyribonuclease B, and carbohydrate A) at 6-week intervals for > or = six consecutive evaluations (total visits=277). RESULTS: Children with large symptom fluctuations (n=15) were compared with children without dramatic fluctuations (n=10). Co-movements of obsessive-compulsive/tic severity and group A streptococcal antibodies were assessed. In subjects with large symptom changes, positive correlations were found between streptococcal titers and obsessive-compulsive severity rating changes (p=.0130). These subjects were also more likely to have elevated group A streptococcal titers during the majority of observations (p=.001). Tic symptom exacerbations occurred more often in the fall/winter months than spring/summer months (p=.03). CONCLUSIONS: Patients with marked obsessive-compulsive/tic symptom changes may be characterized by streptococcal titer elevations and exhibit evidence of seasonal tic exacerbations.  相似文献   
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Relations between lipoprotein indices and the waist/hip ratio (WHR) were examined in normoglycemic subjects (124 women and 63 men). Among women, an atherogenic lipoprotein pattern was strongly associated with WHR. The relation was greater than that of the lipoprotein pattern with either the body mass index or the subscapular/triceps ratio, and was independent of these adiposity measures. The association between low-density-lipoprotein cholesterol (LDL-cholesterol) and WHR was much stronger in thinner women than in those more obese (r = 0.64 vs r = 0.22, p = 0.001 for difference). Men had a more atherogenic lipoprotein pattern than women; however, with allowances for WHR the lipoprotein patterns were similar. These findings suggest that: (1) WHR is more strongly related to plasma lipoproteins than other adiposity measures; (2) there is effect modification by the extent of adiposity for the relation between LDL-cholesterol and WHR; and (3) the adipose distribution may be important in explaining lipoprotein differences between men and women.  相似文献   
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The results of cinefluoroscopic evaluation in 509 patients in whom there was no evidence of prosthetic mitral or aortic valve regurgitation were compared with those in 41 patients who had perivalvular aortic or mitral regurgitation. Rotational motion of the base ring of each prosthesis (base-ring tilt) was measured in at least two views. A base-ring tilt of 7 degrees or more for aortic prostheses or 11 degrees or more for mitral prostheses was associated with an increased incidence of significant perivalvular regurgitation. Likewise, in patients who had multiple studies, a change between studies in base-ring tilt of 4 degrees or more for aortic prostheses or 5 degrees or more for mitral prostheses was associated with significant perivalvular regurgitation. These data suggest that the presence of either an abnormal base-ring tilt or an abnormal increase in base-ring tilt is strong, supportive evidence of partial prosthetic valve dehiscence.  相似文献   
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Experimental models of hypersensitivity pneumonitis are important tools for the study of the pathogenesis of this disease. In this paper we review the characteristics of the main animal models developed until now. The HP models in rats seem to be particularly appropriate for studying pigeon fancier's disease and the HP induced by chemicals, as well as for studying mediators of acute lesions induced by immunocomplexes. However, the HP models developed in rats are of less value in the evaluation of other aspects of the pathogenesis of this clinical entity in humans. The murine models of HP offer several advantages: the ease and simplicity of intranasal administration, the ability to produce acute and subacute pulmonary lesions similar to those found in humans, the possibility of reproducing lesions similar to those of nonaffected exposed subjects and the possibility of pharmacologically modulating the process. Their disadvantages lie in the different pulmonary lymphocyte response and the difficulty in reproducing a model of chronic fibrosis. The HP models in rabbits are extraordinarily useful for evaluating the immunological mechanisms through which subjects repeatedly exposed to the antigen do not develop clinical manifestations. However, the rabbit has several immunological differences when compared to humans, and the effect of some immunomodulators in this animal is different. The models of HP in guinea-pigs have as advantages the ease in handling the animals, the possibility of pharmacological manipulation, and the ability to induce an acute phase that is very similar to that observed in humans. The drawback, however, is the low lymphocyte response and the striking eosinophilic reaction that contrast with the bronchoalveolar data found in HP in humans. In conclusion, there is no ideal model to reproduce all the findings observed in humans, suggesting that the experimental animal and the method of developing HP should be selected on the basis of concrete research aims.  相似文献   
7.
Heterotopic heart transplantation: a radiographic review   总被引:1,自引:0,他引:1  
Heterotopic heart transplantation can be performed in the presence of high pulmonary vascular resistance. The authors call attention to a rare, but potentially life-saving procedure.  相似文献   
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A rapidly growing, malignant schwannoma occurred in a 46-year-old woman with neurofibromatosis. Computed tomography, isotope bone scan, chest roentgenogram, and angiogram are helpful in determining the local extent and distant spread of such musculoskeletal tumors and are useful in planning appropriate surgical management. A well-planned biopsy, however, is essential to accurately determine the histologic diagnosis of the tumor. Clinical and roentgenographic presentation of some benign lesions may mimic malignant tumors. To confirm the diagnosis of a malignant or benign tumor, it is advisable to examine the musculoskeletal tumor histologically before proceeding with the definitive treatment, even if the clinical presentation strongly suggests malignancy.  相似文献   
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