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71.
Journal of Clinical Immunology - Granulocyte transfusions are sometimes used as adjunctive therapy for the treatment of infection in patients with chronic granulomatous disease (CGD). However,...  相似文献   
72.
Organization and expression of human telomere repeat binding factor genes   总被引:1,自引:0,他引:1  
The ends of mammalian chromosomes terminate in structures called telomeres. Recently a human telomere repeat binding factor (TRF1) that binds the vertebrate TTAGGG telomeric repeat in situ was isolated by Chong et al. (1). TRF1 regulates telomere length (2), which is often altered in cancer cells. To understand their genetic organization, TRF1 genes were localized to human chromosomes 13 cen, 21cen, and Xq13 by analysis of human monochromosomal hybrids, and by fluorescent in situ hybridization. We also confirmed the recent localization of a human TRF1 gene to chromosome 8, and provide evidence that this locus is alternatively spliced. In contrast to the TRF1 genes on chromosomes 8 and X, the chromosomes 13 and 21 TRF1 genes contained a 60 bp deletion in the coding region. The results suggest that two distinct forms of TRF1 are expressed and that the TRF1 gene family includes at least three pseudogenes whose dispersal in the human genome may have occurred via cDNA intermediates.  相似文献   
73.
CT Angiography of the Lower Extremities   总被引:1,自引:0,他引:1  
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Studies on the receptive field properties of cat retinal ganglion cells over the past half-century are reviewed within the context of the role played by the receptive field in visual information processing. Emphasis is placed on the work conducted within the past 20 years, but a summary of key contributions from the 1950s to 1970s is provided. We have sought to review aspects of the ganglion cell receptive field that have not been featured prominently in previous review articles. Our review of the receptive field properties of X- and Y-cells focuses on quantitative studies and includes consideration of the function of the receptive field in visual signal processing. We discuss the non-classical as well as the classical receptive field. Attention is also given to the receptive field properties of the less well-studied cat ganglion cells-the W-cells-and the effect of pathology on cat ganglion cell properties. Although work from our laboratories is highlighted, we hope that we have given a reasonably balanced view of the current state of the field.  相似文献   
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Ximelagatran, an oral direct thrombin inhibitor, whose active form is melagatran, was studied using a model of thrombin generation in humans. Healthy male volunteers (18 per group) received ximelagatran (60 mg p.o.), dalteparin (120 IU/kg s.c.) or a control (water p.o.). Shed blood, collected after incision of the forearm with standardised bleeding time devices at pre-dose, and at 2, 4 and 10 h post-dosing, was analysed for markers of thrombin generation. Statistically significant reductions (p < 0.05) in levels of prothrombin fragment 1+2 (F1+2) and thrombin-antithrombin complex (TAT) in shed blood were detected at 2 and 4 h post-dosing in both the ximelagatran and dalteparin groups. Shed blood F1+2 and TAT levels had returned to pre-dose levels at 10 h post-dosing. Using a shed blood model, we demonstrate that the reversible thrombin inhibitor melagatran and, therefore, oral administration of ximelagatran, inhibits thrombin generation in humans after acute activation of coagulation.  相似文献   
78.
The basic mechanisms that underlie neurodegenerative diseases are unknown. Loss of function of specific regions of the brain is due to incapacitation of cells that constitute those regions. Cells can simply stop functioning normally (neurons may cease to transmit signals), or they may die. There is now evidence that the pathology of several neurodegenerative diseases is due to inappropriate apoptosis. This being the case, an understanding of the mediators of apoptosis, their identities, and their role in orchestrating death would be a vital step toward remedying the diseases. The central components of apoptotic pathways, proteases of the caspase family, are present in latent forms in all nucleated cells. Their activity is balanced by specific activation and inactivation events, and the molecular and biochemical controls have been well established in vitro and in model transformed cell lines. In this Mini-Review, we consider the current status of the basic control mechanisms and how these may be subverted during neurodegeneration.  相似文献   
79.
OBJECTIVES: The purpose of this study was to develop and validate a staging algorithm for calcium intake. METHODS: Three hundred seventy-six college-aged females at a private university were randomly selected to participate. After 8.5% of the data were omitted due to incomplete surveys, the sample consisted of 344 female participants. Calcium intake was measured as self-reported consumption with a 26-item food frequency questionnaire. Stages of change classifications were based on a four-item algorithm for calcium intake, and self-efficacy was measured with three items. RESULTS: Significant differences were found between calcium intake levels between precontemplation, contemplation/preparation and action/maintenance. Results also showed that 40% of the participants were in action/maintenance and were consuming the Dietary Reference Intake level of 1,000 mg of daily calcium. Participants in the action and maintenance stages had significantly higher self-efficacy than the preaction group. CONCLUSION: The study suggests that the stages of change algorithm may be used as an effective tool in assessing daily calcium intake among a college female population.  相似文献   
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