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OBJECTIVE: To review epidemiological studies dealing with the temporal and geographic variability in the occurrence of rheumatoid arthritis (RA) and clinical studies that address the variability of severity and manifestations among populations. METHODS: An extensive search of the literature, including a Medline search, was completed. Studies addressing the origin, history, and trends in the occurrence of RA were reviewed first. Next, studies of the prevalence and incidence of RA in different populations were reviewed, and occurrence rates compared. Standardization was attempted by tabulating adult prevalence rates of studies using equivalent sets of criteria. Studies comparing RA patients from two populations were sought next. Finally, studies dealing with explanations of the presumed variability were reviewed. RESULTS: Temporal variability is indicated by paleopathological evidence that RA has existed in the New World since 4000 BC, whereas there is no evidence that it occurred in Europe before the 17th century, or in Africa before the 20th century. Epidemiological studies show a possible trend of decreasing incidence of RA in the United States and Western Europe, whereas reports from Africa note a rising incidence. In white populations of Europe and America, prevalence is approximately 1%, and incidence is 0.03%. Significantly higher rates are found in some North American Indians, and significantly lower rates in some Asian and African populations, even when the different population structures are taken into account. In the latter populations, different patterns of occurrence from those observed in whites emerge, such as greater female preponderance and a much younger peak age at onset. Direct standardized comparisons of two diverse populations of RA patients showed some differences in expression, severity, or manifestations of RA between populations. CONCLUSION: The occurrence and manifestations of RA are temporally and geographically variable.  相似文献   
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Prognostic significance of cathepsin-D in patients with breast cancer   总被引:1,自引:0,他引:1  
The expression of the protease cathepsin-D has been evaluated using an immunohistochemical technique with a polyclonal antibody in paraffin-embedded tissue from 359 patients treated between the years 1975-1981 for Stage I and II breast cancer. One hundred and twenty seven patients (35%) have strongly positive, granular staining, 138 (38%) are intermediately stained in the cytoplasm, and in 94 (26%) no staining is observed. There is a strong positive association between expression of cathepsin-D and the presence of tumour in axillary lymph nodes (P < 0.006). Expression of the protease is associated with significantly poorer survival of patients in univariate analysis (P = 0.025); however, this is not independent of other tumour variables.  相似文献   
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Urinary incontinence is most frequently associated with the elderly, particularly women, and is often thought of as inevitable. However, orthopaedic nurses encounter incontinence as a response to alterations in orthopaedic health. This article reviews the types of urinary incontinence, with emphasis on those which may most directly result from orthopaedic problems. It will also help the nurse differentiate between types of incontinence in a way that will clarify appropriate interventions.  相似文献   
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The rostral migratory stream consists of a large number of cells migrating from the lateral ventricles to the rostral telencephalon, primarily the olfactory bulb. The pathway continually provides neuro- and glioblasts throughout life. The present paper indicates that a considerable number of cells undergo apoptotic cell death en route, even in young (day 3) rats when presumably many vacant sites are still available in the developing brain.  相似文献   
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Cell cycle. The NIMA kinase joins forces with Cdc2   总被引:1,自引:0,他引:1  
The NIMA and Cdc2 protein kinases cooperate to regulate mitosis in Aspergillus nidulans. NIMA-related pathways have now begun to emerge in higher eukaryotes.  相似文献   
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