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Progression rates of Alzheimer's disease (AD) vary considerably, and they are particularly difficult to predict in patients with mild cognitive impairment. We performed a prospective multicenter cohort study in 186 patients with possible or probable AD, mostly with presenile onset. In a cross-sectional analysis at entry, impairment of glucose metabolism in temporoparietal or frontal association areas measured with positron emission tomography was significantly associated with dementia severity, clinical classification as possible versus probable AD, presence of multiple cognitive deficits and history of progression. A prospective longitudinal analysis showed a significant association between initial metabolic impairment and subsequent clinical deterioration. In patients with mild cognitive deficits at entry, the risk of deterioration was up to 4.7 times higher if the metabolism was severely impaired than with mild or absent metabolic impairment. Copyrightz1999S.KargerAG, Basel  相似文献   
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We studied the immunologic function of 19 sexually active homosexual men, ten of whom had persistent lymphadenopathy. Analysis of mononuclear cell populations distinguished homosexuals from heterosexual controls since, as a group, homosexuals had increased percentages of natural killer cells (Leu 7+), decreased helper-inducer T lymphocytes (OKT-4+), increased suppressor/cytotoxic (OKT-8+) T lymphocytes, low OKT-4:OKT-8 ratios, and depressed mitogenic responses. Homosexuals without lymphadenopathy were distinguishable from controls by increased percentages of Ia+ cells, decreased OKT-4+ cells, and decreased OKT-4:OKT-8 ratios. Four had positive findings simultaneously for hepatitis B surface antigen (HBsAg) and surface antibody, and five had positive findings for HBsAg alone. Homosexuals with lymphadenopathy were distinguishable from controls by increased percentages of Leu 7+ cells, increased total lymphocyte numbers per cubic millimeter, decreased percentages of both OKT-4+ and OKT-8+ cells, abnormal OKT-4:OKT-8 ratios, and depressed mitogenic responses. Only histories of larger numbers of sexually acquired diseases, higher numbers of OKT-8+ cells per cubic millimeter, and lower mitogenic responses in homosexuals with lymphadenopathy distinguished this group from homosexuals without lymphadenopathy. Furthermore, none of the nine patients tested in this group was HBsAg positive. We conclude that homosexuals without lymphadenopathy are distinguishable from those with lymphadenopathy by both immunologic and serologic abnormalities.  相似文献   
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Manometry of the alimentary tract is a valuable and widely used means to evaluate and diagnose the function of the alimentary tract. However, the measurement can be inconvenient due to the invasive method used, and the many factors affecting results. Research on colonic pressure data is even more insufficient. This paper deals with colonic pressure data via an improved method ensuring that pressure data of the whole colon is available. The data is analysed based on the learning vector quantization (LVQ) method. Testing results show that this method distinguishes the normal data and the abnormal data, consistently with the original diagnoses. This method can serve as an assistant diagnosis of colonic motility and contributes to further research on colonic motility based on pressure data.  相似文献   
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