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41.
Summary It has been recently demonstrated in anesthetized, sinoaortic denervated-vagotomized (SAD+Vx) cats that epicardial or intracoronary (IC) bradykinin (BK) evokes an increase in efferent renal nerve activity (RNA) and a pressor response which is mediated by the cardiac sympathetic afferent nerves. The purpose of this study was to compare the effect of epicardial, IC, and left atrial (LA) administration of BK on arterial blood pressure (ABP) and RNA in intact and SAD+Vx cats and dogs. A total of seven cats and eight dogs anesthetized with chloralose were prepared with a left circumflex coronary arterial catheter (dogs) or a LA catheter (cats). Changes in ABP and RNA were determined in both dogs and cats when 1 to 100 g/ml of BK was applied to the anterior surface of the left ventricle or injected IC or LA (0.3 and 3.0 g/kg BK) in the intact and SAD+Vx state. In both the intact and SAD +Vx cat, a pressor response was consistently elicited with epicardial BK. In the SAD+Vx state, epicardial BK increased ABP by 33.4±4.7 mm Hg (p<.001). RNA followed this same trend showing a consistent and significant increase with both LA and epicardial BK (+24.8±8.4% in the SAD+Vx state; P<.05). Changes in RNA in dogs were highly variable with epicardial and IC BK in intact and in SAD Vx dogs, resulting in insignificant changes in this parameter. The results of this study demonstrate that the reflex effects of stimulation of cardiac sympathetic afferents by BK are species specific and need not evoke an increase in peripheral sympathetic outflow.Supported by National Institutes of Health Gran #HL-22594 and American Heart Association Grant # 81672.  相似文献   
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We have described the epidemiological analysis of one aspect of the King's College Hospital computerised data base; namely initial intraocular pressure as an indicator of visual field loss. The methods involved the use of the four-fold table to determine sensitivity and specificity at different pressure levels. From these results (1) the changes in the pre and post test probability of field loss are calculated and (2) a sensitivity/specificity trade off curve or decision curve is constructed. In this way the optimal cut-off level or operating point for a population of specific type and composition can be determined. The factors concerned in decision making are always complex but such an approach allows a rational and quantifiable alternative to reliance on clinical impression and intuition. The results have significance in relation to decisions on the management of patients and on population screening programmes for glaucoma.  相似文献   
43.
The structure of schizotypy: a pilot multitrait twin study   总被引:3,自引:0,他引:3  
This report of a pilot study examines 29 pairs of twins from a population-based registry on whom four domains of schizotypy have been measured: personal interview using the Structured Interview for Schizotypy, self-report questionnaire formed from eight published self-report scales, attentional battery of eight individual tests, and root mean square error on smooth pursuit eye tracking. Analyzing the twins as individuals revealed two independent dimensions of clinically rated schizotypy (positive symptom schizotypy and negative symptom schizotypy) and two independent dimensions of self-rated schizotypy (positive trait schizotypy and trait anhedonia). Positive symptom schizotypy was highly correlated with positive trait schizotypy, but not with attentional dysfunction or eye-tracking error. By contrast, negative symptom schizotypy was significantly related to trait anhedonia, attentional dysfunction, and eye-tracking error. Correlations in monozygotic and dizygotic twins suggested that genetic factors were important in all four domains of schizotypy. Except for eye-tracking error, the results are more consistent with a dimensional than a "disease" model of schizotypy. Replication of these results with a larger group of subjects is needed.  相似文献   
44.
Awareness of illness in schizophrenia   总被引:6,自引:0,他引:6  
This article reviews the literature on "poor insight" or unawareness of illness in schizophrenia. A large body of knowledge representing several different perspectives on insight has developed. This work can be divided into three broad categories, suggesting an important role for insight in the phenomenology, pathophysiology, and treatment of schizophrenia. The argument is made here that many of the self-awareness deficits observed in schizophrenia are of diagnostic significance, are neurally based, and are indispensable in guiding treatment decisions. In addition, this article proposes guidelines for assessing unawareness of illness in schizophrenia and discusses the relevance of such deficits to the diagnosis of schizophrenia.  相似文献   
45.
In 1975, twelve years after enactment of the Community Mental Health Centers Act, we find one of the greatest obstacles to fulfillment of our hopes to be pervasive hostility to acceptance of the mentally ill in many communities. The River Region Program has hurdled this obstacle by breaking the artificially large mental health catchment areas into manageable segments of 16 smaller service areas close to the people it serves in seven counties of Kentucky. In each of these service areas it has involved a broad spectrum of citizens in the planning of every service. All of this is of particular relevance today in light of the Supreme Court's D,onaldson decision, that mentally ill persons cannot be confined involuntarily if they are not dangerous and can live safely in the outside world. The outside world must be prepared to receive these people, and we in the mental health field must do our job in this vital preparation.Mr. Gorman originally presented this paper as a speech at the Annual Dinner, of the River Region Mental Health — Mental Retardation Board in Louisville, Kentucky, on June 20, 1975.  相似文献   
46.
BACKGROUND AND PURPOSE: Intravenous tissue plasminogen activator (tPA) administered within 3 hours of symptom onset is the first available effective therapy for acute ischemic stroke (AIS). Few data exist, however, on its use in very elderly patients. We examined the characteristics, complications, and short-term outcome of AIS patients aged >/=80 years treated with tPA. METHODS: Patients aged >/=80 years (n=30) were compared with counterparts aged <80 years (n=159) included in the tPA Stroke Survey, a US retrospective survey of 189 consecutive AIS patients treated with intravenous tPA at 13 hospitals. RESULTS: Risk of intracerebral hemorrhage (fatal, symptomatic, and total) was 3%, 3%, and 7% in the elderly age group and 2%, 6%, and 9%, respectively, in their younger counterparts (P=NS for all comparisons). Likelihood of favorable outcome, defined as modified Rankin score 0 to 1, National Institutes of Health Stroke Scale score /=80 years was identified.  相似文献   
47.
In the United States, medical care consumes approximately $1.2 trillion annually (14% of the gross domestic product) and involves 250,000 physicians, almost 1 million nurses, and countless other providers. While the Information Age has changed virtually every other facet of our life, the education of these healthcare professionals, both present and future, is largely mired in the 100-year-old apprenticeship model best exemplified by the phase "see one, do one, teach one." Continuing medical education is even less advanced. While the half-life of medical information is less than 5 years, the average physician practices 30 years and the average nurse 40 years. Moreover, as medical care has become increasingly complex, medical error has become a substantial problem. The current convulsive climate in academic health centers provides an opportunity to rethink the way medical education is delivered across a continuum of professional lifetimes. If this is well executed, it will truly make medical education better, safer, and cheaper, and provide real benefits to patient care, with instantaneous access to learning modules. At the Center for Advanced Technology in Surgery at Stanford we envision this future: within the next 10 years we will select, train, credential, remediate, and recredential physicians and surgeons using simulation, virtual reality, and Web-based electronic learning. Future physicians will be able to rehearse an operation on a projectable palpable hologram derived from patient-specific data, and deliver the data set of that operation with robotic assistance the next day.  相似文献   
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