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R W Ashford 《Annals of tropical medicine and parasitology》1991,85(1):189-198
A breakdown of the human parasite fauna shows approximately 270 species, with almost equal numbers of nematodes, flukes and protozoa and smaller numbers of arthropods and tapeworms. More than 70% are 'adventitious' species for which man is an incidental host. Only 16% are 'core' species, dependent on man for their survival. For 26% man is the usual source of human infection, and for 51% the source is other mammals. A sequence is illustrated showing how parasites may arrive by the host-transfer or co-evolutionary pathways. Adventitious parasites have a narrower geographical range than core species. The richest representation of the major species is in the Aethiopian Zoogeographical Region and the poorest is in the Australasian. Some 14 pairs of closely related forms occur in the main fauna. Some implications of this analysis with respect to man's early history are discussed speculatively. 相似文献
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J W Ashford V Kumar M Barringer M Becker J Bice N Ryan S Vicari 《International psychogeriatrics / IPA》1992,4(1):55-74
Diagnosis of dementia needs to be complemented by precise determination of disease severity across the broad spectrum of disease progression. The Mini-Mental State Exam (MMS), the Activities-of-Daily-Living assessment (ADL) and the Clinical Dementia Rating scale (CDR) were modified for direct comparability and administered to 112 outpatients and 45 nursing home residents with a range of dementia severity from mild to profound. The scales showed the highest correlations for the probable Alzheimer's disease patient group (62) (Global Assessment of Dementia; GAD vs. ADL: r = 0.91; Extended Mini-Mental Assessment; EMA vs. GAD: r = 0.91; ADL vs. EMA: r = 0.86). For these patients, scores on the individual scales tended to be similar. Disparity among the three scores for individual cases was associated with the presence of comorbidities. The high correlations and correspondence among these scales demonstrate their reliability, validity, and utility in the assessment of dementia severity. The use of an average of these measures, with their increased precision, may give a more accurate indication of dementia severity over a broader range of impairment. 相似文献
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Mahadevaiah SK; Odorisio T; Elliott DJ; Rattigan A; Szot M; Laval SH; Washburn LL; McCarrey JR; Cattanach BM; Lovell-Badge R; Burgoyne PS 《Human molecular genetics》1998,7(4):715-727
An RNA-binding motif (RBM) gene family has been identified on the human Y
chromosome that maps to the same deletion interval as the 'azoospermia
factor' (AZF). We have identified the homologous gene family (Rbm) on the
mouse Y with a view to investigating the proposal that this gene family
plays a role in spermatogenesis. At least 25 and probably >50 copies of
Rbm are present on the mouse Y chromosome short arm located between Sry and
the centromere. As in the human, a role in spermatogenesis is indicated by
a germ cell-specific pattern of expression in the testis, but there are
distinct differences in the pattern of expression between the two species.
Mice carrying the deletion Yd1, that maps to the proximal Y short arm, are
female due to a position effect resulting in non-expression of Sry ;
sex-reversing such mice with an Sry transgene produces males with a high
incidence of abnormal sperm, making this the third deletion interval on the
mouse Y that affects some aspect of spermatogenesis. Most of the copies of
Rbm map to this deletion interval, and the Yd1males have markedly reduced
Rbm expression, suggesting that RBM deficiency may be responsible for, or
contribute to, the abnormal sperm development. In man, deletion of the
functional copies of RBM is associated with meiotic arrest rather than
sperm anomalies; however, the different effects of deletion are consistent
with the differences in expression between the two species.
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In this review, evidence is provided that apolipoprotein E (apoE) genotype accounts for the majority of Alzheimer's disease (AD) risk and pathology. The three major human isoforms, apoE2, apoE3, and apoE4, are encoded by different alleles (2, 3, 4) and regulate lipid metabolism and redistribution. ApoE isoforms differ in their effects on AD risk and pathology. Clinical and epidemiological data have indicated that the 4 allele may account for 50% of AD in the United States. Further, the rarity of AD among carriers of the 2 allele suggests that allelic variations in the gene encoding this protein may account for over 95% of AD cases. ApoE4 disrupts memory function in rodents. Further studies have indicated that fragments of apoE may contribute to both plaque and tangle formation. Thus, the epidemiologic and basic science evidence suggest that apoE genotype accounts for the vast majority of AD risk and pathology. 相似文献
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Ashford Kristin McCubbin Andrea Barnett Janine Blair Lisa M. Lei Feitong Bush Heather Breland Alison 《Maternal and child health journal》2021,25(8):1175-1181
Maternal and Child Health Journal - In the US, approximately 8% of pregnant women smoke, and 5–11.9% currently use ENDS products. The health effects of ENDS use are debated; however, most... 相似文献
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