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A 41-year-old woman from the Cape Verde Islands, Africa, who had been residing in the United States for 11 months was found to have human immunodeficiency virus type 2 (HIV-2)-associated acquired immunodeficiency syndrome (AIDS). Antibody to HIV-2 was found by enzyme immunoassay and was verified by radioimmunoprecipitation. The patient was being treated for pulmonary tuberculosis at the time of her admission to our institution. Further laboratory and clinical evaluation at our facility revealed depressed CD4 lymphocytes, oral candidiasis, and cryptococcal meningitis with indeterminate results on serologic testing for HIV type 1 (HIV-1). The biopsy specimen of a lesion in the right occipital lobe of the brain documented Toxoplasma gondii, indicating a clinical diagnosis of AIDS. To our knowledge, our study presents the first known patient with HIV-2-associated AIDS in the United States. Our patient provides further evidence that HIV-2 causes severe immunodeficiency and opportunistic infection. The condition should be suspected in the face of normal or repeatedly equivocal HIV-1 antibody test results in the presence of clinically documented AIDS.  相似文献   
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Summary A 34-year-old man affected by exercise intolerance, mild proximal weakness and severe lactic acidosis is described. Muscle biopsy revealed mitochondrial abnormalities and an increase of cytochrome c oxidase histochemical reaction. Biochemical investigations on isolated muscle mitochondria as well as polarographic studies revealed a mitochondrial NADH-CoQ reductase (complex I) deficiency. Mitochondrial dysfunction was confirmed by 31P nuclear magnetic resonance spectroscopy. Immunological investigation showed a generalized reduction of all complex I polypeptides. Genetic analysis did not reveal mitochondrial DNA deletions. The biochemical defect was not present in the patient's muscle tissue culture. Metabolic measurements and functional evaluation showed a reduced mechanical efficiency during exercise.  相似文献   
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Although numerous studies have demonstrated reliable relationships between various human performance measures and time of day, disagreement exists concerning the shape of these relationships and their dependence on task variables. Most perceptual-motor tasks emphasize responsiveness to exteroceptive stimuli. We used a multiple force-band discrimination task that requires responsiveness to both exteroceptive and proprioceptive information. Results for a response duration measure showed a quadratic time of day trend similar to previously reported performance tasks. Response latency to the force emission cue and number of correct inband force emissions showed cubic time of day trends not typically reported in the time of day and performance literature. These results have implications for time-of-day effects on real world perceptual performance.  相似文献   
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A large number of chorionic villi samples obtained from women undergoing elective first trimester termination of pregnancy was analysed by enzyme assays similar to those applied to cultured amniotic cells. The levels of 15 lysosomal enzymes were compared to those observed in tissue cultures of amniotic cells obtained through amniocentesis at 16-18 weeks of pregnancy and the results were discussed in order to assess the usefulness of trophoblast biopsy for first trimester diagnosis of hereditary lysosomal diseases. The data suggest the applicability of this source of fetal cells for prenatal diagnosis of fifteen respective genetically determined enzyme deficiencies with the probable exception of alpha-L-iduronidase deficiency. Enzyme determinations were performed on chorionic villi samples of two pregnancies at risk for Tay-Sachs disease, three pregnancies for GM1 gangliosidosis type 1, one for mucopolysaccharidosis type VI and one for Wolman's disease.  相似文献   
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