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Arginine vasopressin (AVP) has been localized in numerous extrahypothalamic brain regions and in the spinal cord. The results of intracerebroventricular AVP injections and microinjection of AVP into the brain stem suggest that this peptide, acting centrally at higher levels, may influence cardiovascular function. No function for the AVP occurring at spinal levels has been reported. In this study we report that AVP, in picomole quantities, increased arterial blood pressure and integrated heart rate in a dose-dependent manner following intrathecal application to the thoracic region in the rat. This response was not blocked by intravenous administration of the AVP antagonist d(CH2)5-d-Tyr-VAVP. These results suggest that AVP, acting within the spinal cord, may alter neural outflow regulating blood pressure and heart rate. 相似文献
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Advances in technological development have produced an ever-increasing pressure for new and different raw materials to keep pace with changing industrial needs. Many new and useful properties of plants may be discovered through the modern chemistry and technology of utilization research. The U. S. Department of Agriculture’s search for new industrial crops is a coordinated botanical and utilization research program. 相似文献
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Bernard L. Tucker George G. Lindesmith Quentin R. Stiles Richard K. Hughes Bert W. Meyer 《The Western journal of medicine》1977,126(3):179-183
Myocardial revascularization has been carried out by us in 67 patients 70 years of age or older. Advanced coronary artery disease was found at angiography in more than two thirds of the patients. The postoperative morbidity and mortality compare very favorably with those in younger patients. The early and late mortality in the 67 patients was 4.5 percent and 6.0 percent, respectively. Fifty-seven survivors have been followed an average of 21 months; for most patients there has been a pronounced improvement in clinical classification. Properly selected, patients of advanced age can undergo successful revascularization surgical procedures. The adequacy of function of the left ventricle, proper timing of the surgical operation and an aggressive yet realistic approach seem to be major determinants for a good result. 相似文献
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Mutations in the parkin gene cause early-onset, autosomal recessive Parkinson's disease. Parkin functions as an E3 ubiquitin ligase to mediate the covalent attachment of ubiquitin monomers or linked chains to protein substrates. Substrate ubiquitination can target proteins for proteasomal degradation or can mediate a number of non-degradative functions. Parkin has been shown to preserve mitochondrial integrity in a number of experimental systems through the regulation of mitochondrial fission. Upon mitochondrial damage, parkin translocates to mitochondria to mediate their selective elimination by autophagic degradation. The mechanism underlying this process remains unclear. Here, we demonstrate that parkin interacts with and selectively mediates the atypical poly-ubiquitination of the mitochondrial fusion factor, mitofusin 1, leading to its enhanced turnover by proteasomal degradation. Our data supports a model whereby the translocation of parkin to damaged mitochondria induces the degradation of mitofusins leading to impaired mitochondrial fusion. This process may serve to selectively isolate damaged mitochondria for their removal by autophagy. 相似文献
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Specific Activity of Brain Palmitoyl-CoA Pool Provides Rates of Incorporation of Palmitate in Brain Phospholipids in Awake Rats 总被引:3,自引:1,他引:3
Eric Grange Joseph Deutsch Quentin R. Smith Michael Chang Stanley I. Rapoport A. David Purdon 《Journal of neurochemistry》1995,65(5):2290-2298
Abstract: In vivo rates of palmitate incorporation into brain phospholipids were measured in awake rats following programmed intravenous infusion of unesterified [9,10-3 H]palmitate to maintain constant plasma specific activity. Animals were killed after 2–10 min of infusion by microwave irradiation and analyzed for tracer distribution in brain phospholipid and phospholipid precursor, i.e., brain unesterified palmitate and palmitoyl-CoA, pools. [9,10-3 H]Palmitate incorporation into brain phospholipids was linear with time and rapid, with >50% of brain tracer in choline-containing glycerophospholipids at 2 min of infusion. However, tracer specific activity in brain phospholipid precursor pools was low and averaged only 1.6–1.8% of plasma unesterified palmitate specific activity. Correction for brain palmitoyl-CoA specific activity increased the calculated rate of palmitate incorporation into brain phospholipids (0.52 nmol/s/g) by ∼60-fold. The results suggest that palmitate incorporation and turnover in brain phospholipids are far more rapid than generally assumed and that this rapid turnover dilutes tracer specific activity in brain palmitoyl-CoA pool owing to release and recycling of unlabeled fatty acid from phospholipid breakdown. 相似文献
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IL-27 activates human monocytes via STAT1 and suppresses IL-10 production but the inflammatory functions of IL-27 are abrogated by TLRs and p38 总被引:2,自引:0,他引:2
IL-27 is a member of the IL-12 family of cytokines that activates the Jak-STAT signaling pathway in a context-dependent manner and has pleiotropic effects on acquired immunity. IL-27 has the capacity to promote early stages of Th1 generation, but recent evidence has suggested a predominant suppressive effect on Th1, Th2, and Th17 differentiation. Although modest suppressive effects of IL-27 on myeloid lineage cells have been observed, there is limited knowledge about the role of IL-27 in the regulation of innate immunity. In this study we report that although in resting murine macrophages IL-27 had minimal if any effects, in resting human monocytes IL-27 had profound proinflammatory functions. IL-27 activated a STAT1-dominant pattern of signaling in human monocytes with the consequent activation of STAT1-dependent inflammatory target genes. IL-27 primed monocytes for augmented responses to TLR stimulation in a STAT1-dependent manner, altered IL-10 signaling, and attenuated IL-10-induced gene expression. Strikingly, IL-27 strongly suppressed TLR-induced IL-10 production in human monocytes. However, the proinflammatory effects of IL-27 on human monocytes were rapidly abrogated by LPS via a p38-mediated mechanism that inhibited IL-27 signaling. Our findings identify a predominantly proinflammatory function for IL-27 in human monocytes and suggest a mechanism by which the activating effects of IL-27 on innate immunity are attenuated as an immune response proceeds and IL-27 transitions to predominantly suppressive effects on acquired immunity. 相似文献
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