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Coronary magnetic resonance angiography (CMRA) is a technique in clinical evolution. Current clinical applications include assessment for coronary anomalies, aneurysms, bypass graft patency, and, in experienced centers, the exclusion of proximal and multivessel coronary artery disease (CAD). As local expertise increases and more extensive multicenter data become available, additional applications will be established. CMRA promises to supplement and in some cases obviate the need for X-ray contrast angiography, and to expand our understanding of the pathophysiology of CAD. Zusammenfassung Die Magnetresonanzangiographie der Koronargefäße (CMRA) ist eine sich ständig weiterentwickelnde Technik. Etablierte Anwendungen sind zurzeit die Beurteilung von koronaren Anomalien, Aneurysmen und der Durchgängigkeit von Bypasses. Auch der Ausschluss proximaler Koronarstenosen und einer koronaren Mehrgefäßerkrankung ist in einigen spezialisierten Zentren möglich. Mit zunehmender Erfahrung der jeweiligen Anwender und der Verfügbarkeit von Ergebnissen großer multizentrischer Studien können zukünftig weitere klinische Anwendungen etabliert werden. In der Zukunft könnte die CMRA ergänzende Informationen zur Indikationsstellung einer konventionellen Röntgenangiographie bringen und in einigen Fällen diese Untersuchung sogar ersetzen. Die CMRA wird unseren Einblick in die Pathophysiologie der koronaren Herzerkrankung sicher erweitern.  相似文献   
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We report a case of mild visuo-spatial neglect consequent upon right-hemisphere stroke. At the time of testing, the patient had a complete left visual field deficit but only a very slight left hemiparesis. Under conventional testing conditions, line bisection performed with the right hand showed more severe left neglect than when performed with the left hand. This pattern of performance could, however, be modified, both quantitatively and qualitatively, by changing the starting position of the patient's hand when bisecting horizontal lines. The results suggest that spatio-motor cueing has a more profound effect upon task performance than does differential hemispheric activation per se. We also provide a demonstration that, in a normal subject, the starting position of the hand is likewise a crucial determinant of task performance. In this case, however, there is also an interaction between the hand (and hence hemisphere) deployed and the position of that hand in space.  相似文献   
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Effects of methylphenidate and d-amphetamine on timing in the rat   总被引:4,自引:0,他引:4  
Rats were trained to press a lever for food pellets provided according to a fixed interval 60-sec schedule of reinforcement. Probe trials (peak trials) assessed responding over two-min periods with no pellet delivered. The low rates of responding found early and late in probe trials were increased by methylphenidate and 1.0 mg/kg d-amphetamine (rate-dependent effect). Further, the mean time of responding (peak time) was shortened for both drugs (timing effect).  相似文献   
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Conventional risk factors have very low predictive power in identifying haemodialysis patients at high risk of vascular accidents. A role for apolipoprotein E isotypes was looked for in a small, but rigorously defined, cohort of longterm haemodialysis patients. In individuals with high vascular risk, as identified by higher common carotid intima/media thickness, we found an excess of apolipoprotein E4 alleles. This preliminary result requires confirmation in large patient cohorts.   相似文献   
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The role of the advanced practice nurse is evolving in the specialty of gastroenterology, requiring flexibility and an openness to change on the part of the practitioner. The gastroenterology advanced practice nurse performs history and physical assessments, orders diagnostic studies, determines medical and nursing diagnoses, prescribes and evaluates pharmacologic and other therapeutic regimens, manages followup care, and evaluates patient outcomes. The advance practice nurse also provides patient, family, and group education and screening programs. Collaboration with other healthcare professionals; serving as a mentor and as a consultant; participating in continuing education, research and quality management; and providing professional leadership underscore the professional aspects of advance practice nurse activities. The focus of this article is the educational role of the advanced practice nurse. The body of knowledge applicable to the educational role is discussed, in addition to contributory professional activities.  相似文献   
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Opioid peptides have profound effects on gut motility. To assess their actions on enteric neurons regulating sphincteric smooth muscle, the ability of several opioid agonists to antagonize the neuronally induced relaxation of canine lower esophageal sphincter smooth muscle was examined. Opioid peptides selective for mu (FK 33-824) or delta [( D-Pen2,D-Pen5]enkephalin) receptors produced a concentration dependent inhibition of electrical field stimulation (EFS)-induced relaxation. In contrast, neither kappa (ketocycloclazine) or sigma (SK & F 10047) opioid agonists were potent inhibitors of EFS-induced relaxation. This inhibition was relatively selective for opioid agonists since BHT 933 (alpha 2 adrenoceptor agonist) and SK & F 89124 (D2 dopamine agonist) did not inhibit EFS-induced relaxation. Furthermore, naloxone antagonized the effects of both FK 33-824 and DPDPE. These functional data suggest that opioid receptors are present on sphincteric intrinsic inhibitory neurons and that stimulation of these neuronal receptors can regulate lower esophageal sphincter relaxation.  相似文献   
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