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1.
The majority of studies axamining the regulation of coronary blood flow and vascular resistance have considered the coronary circulation as being composed of large conduit vessels and resistance vessels. Recently, it has become apparent that regulation of coronary microvascular resistance is not distributed uniformly, but varies across different segments or microdomains of the vasculature. Generally, small arterioles, those less than 100 m in diameter, respond differently than larger arterioles and small arteries. There are major differences in the level of autoregulatory control, myogenic control, endothelial modulation and control by metabolic factors across these various microvascular domains. There are also transmural variations which may account for some of the differences in coronary blood observed between epicardial and endocardial regions. In addition, interactions between these various regulatory mechanisms further complicate the understanding of coronary microvascular regulation. Importantly however, it may be these complex interactions and heterogeneous regulatory mechanisms which allow for adequate perfusion of the myocardium under an extreme range of metabolic conditions. This segmental distribution of regulation suggests an integrative hypothesis of regulation whereby a variety of mechanisms play a role in the overall response.Invited Contributions to the Symposium Regulation of coronary blood flow, held at the XV. World Congress of the International Society for Heart Research in Prague 1995 相似文献
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Wever G. K. Althausen T. L. Biskind G. R. Kerr WM. J. 《The American journal of digestive diseases》1935,2(2):93-99
The American Journal of Digestive Diseases - In our patients with acute hepatitis, as a group, the Rose Bengal test was positive in 94 per cent, and the modified glucose tolerance test in 93 per... 相似文献
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Pretreatment of recipients with the monoclonal antibody (MoAb) S5 facilitates engraftment of bone marrow from mismatched, unrelated donors in the canine transplantation model. In the direct comparisons reported here, the S5 glycoprotein (gp) was found to have structural homology to CD44 that in humans has been implicated in adhesive interactions of one type of effector cell, the lymphocyte. The S5 antigen and gp90Hermes-1 exhibited codistribution on canine peripheral blood cells. Both S5 and Hermes-1 (anti-CD44) MoAbs recognized 90-Kd species in radioimmune precipitations of 125I surface-labeled canine peripheral blood lymphocytes and bone marrow cells. Competitive antibody binding experiments showed that the epitope detected by S5 was distinct from that bound by Hermes-1 but overlapped with those defined by two other known anti-CD44 reagents, IM7 and Hutch-1. Sequential immunoprecipitation with S5 and Hermes-1 indicated that the two antibodies recognize the same or overlapping subsets of membrane gps. Tryptic digestion of S5 and anti-CD44 immunoprecipitates generated two major iodinated peptides of 27 and 35 Kd in both cases, a further indication of structural homology. Similarly, after N-glycanase digestion, S5 and CD44 immunoprecipitates were resolved to a single 68- Kd species. These findings suggest that CD44-mediated adhesive events may affect the fate of transplanted hematopoietic cells. The previous implications of this gp in T-lymphocyte activation and lymphocyte adhesion to endothelium thus provide useful paradigms to analyze its function in the bone marrow transplant setting. 相似文献
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S Desai T Diener BJ-K Tan NJ Lowry C Talukdar WM Chrusch S Wiebe 《The Canadian Journal of Infectious Diseases & Medical Microbiology》2014,25(4):227-228
The present article reports a case involving an immunocompetent, previously well child who, despite two previous doses of inactivated poliovirus vaccine, developed severe flaccid paralysis consistent with polio after receiving oral polio vaccine. 相似文献
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Modern population based oral health management requires a complete understanding of the impact of disease in order to provide efficient and effective oral health care and guidance. Periodontitis is an important cause of tooth loss and has been shown to be associated with a number of systemic conditions. The impact of oral conditions and disorders on quality of life has been extensively studied. However, the impact of periodontitis on quality of life has received less attention. This review summarizes the literature on the impact of periodontitis on oral health‐related quality of life (OHRQoL). Relevant publications were identified after searching the MEDLINE and EMBASE electronic databases. Screening of titles and abstracts and data extraction was conducted. Only observational studies were included in this review. Most of the reviewed studies reported a negative impact of periodontitis on OHRQoL. However, the reporting standards varied across studies. Moreover, most of the studies were conducted in developed countries. 相似文献
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