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In this investigation, an isolated, perfused rat stomach system was used to elucidate the roles of histamine, serotonin, and the action of cimetidine, methysergide, and propranolol in relation to the in vivo and in vitro administration of compound 48/80. While histamine administered both in vivo and in vitro stimulated acid secretion in the perfused rat stomach, serotonin, added in vitro, inhibited histamine-induced gastric acid secretion. Cimetidine, given either in vivo or in vitro, blocked histamine-induced acid secretion, and methysergide, but not propranolol, reversed the serotonin-induced inhibition of histamine-stimulated acid secretion. Compound 48/80, given in vitro, caused gastric acid secretion that was blocked by pretreatment with cimetidine. Administered in vivo, however, compound 48/80 inhibited both basal and histamine-stimulated acid secretion. This inhibition was partially reversed by pretreatment with methysergide. The absence of inhibition of acid secretion by in vitro-administered compound 48/80 may be related to the timing of the serotonin effect. When serotonin was given prior to histamine, it blocked acid secretion, whereas no inhibition occurred when serotonin was administered together with histamine. None of the other agents investigated affected basal acid secretion.  相似文献   
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Background: Sustained hypotension, cardiogenic shock, and heart failure all imply a poor prognosis in acute myocardial infarction (MI). We assessed the benefit of adding 48 hours of intra-aortic balloon counterpulsation (IABP) to standard treatment for MI, in an international trial among hospitals without primary angioplasty capabilities.Methods: We randomized 57 patients with MI complicated by sustained hypotension, possible cardiogenic shock, or possible heart failure to receive either fibrinolytic therapy and IABP or fibrinolysis alone. The primary end point was all-cause mortality at 6 months.Results: In all, IABP was inserted in 27 of 30 assigned patients a median 30 minutes after fibrinolysis began and continued for a median 34 hours. Of the 27 patients assigned to fibrinolysis alone, 9 deteriorated such that IABP was required. The IABP group was at slightly higher risk at baseline, but the incidence of the primary end point did not differ significantly between groups (34% for combined treatment versus 43% for fibrinolysis alone; adjusted P = 0.23). Patients with Killip class III or IV showed a trend toward greater benefit from IABP (6-month mortality 39% for combined therapy versus 80% for fibrinolysis alone; P = 0.05).Conclusions: While early IABP use was not associated with a definitive survival benefit when added to fibrinolysis for patients with MI and hemodynamic compromise in this small trial, its use suggested a possible benefit for patients with the most severe heart failure or hypotension.Abbreviated Abstract. We assessed the benefit of adding 48 hours of intra-aortic balloon counterpulsation to fibrinolytic therapy among 57 patients with acute myocardial infarction complicated by sustained hypotension, possible cardiogenic shock, or possible heart failure. The primary end point, mortality at 6 months, did not differ between groups (34% for combined treatment versus 43% for fibrinolysis alone [n = 27]; adjusted P = 0.23), although patients with Killip class III or IV did show a trend toward greater benefit from IABP (39% for combined therapy versus 80% for fibrinolysis; P = 0.05).  相似文献   
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BACKGROUND AND AIMS: The aim of the present study is to describe the effects of aging on various cognitive domains (global cognitive function, executive function, motor speed) in a population sample of elderly men, and to describe how their age-related changes are influenced by education, depression, or prevalent cerebrovascular accidents (CEVD). METHODS: A cross-sectional observational study was conducted in a cohort of 334 men, 65 to 95 years old, living in rural communities, participating in the Italian cohort of two population studies--MATISS (Malattie cardiovascolari ATerosclerotiche Istituto Superiore di Sanità) and FINE (Finland, Italy, Netherlands, Elderly). Global cognitive function was measured by the Mini-Mental State Examination (MMSE), executive function by the Stroop test, motor speed by the Purdue Pegboard test, and depression by the CES-D test. Prevalence of cerebrovascular accidents (CEVD), myocardial infarction, and diabetes were evaluated by a questionnaire and a clinical examination. Blood pressure, and total and HDL cholesterol were measured. Current smoking status was self-reported. RESULTS: An age-associated decline in global cognitive functions, executive functions, and motor speed was observed. The decline is more apparent after the age of 85 for the MMSE, and after 75 for executive functions and motor speed. Logistic regression analysis revealed that age was independently associated with altered global cognitive functions, executive functions, and motor speed, even after adjusting for education, depression or prevalent CEVD. CONCLUSIONS: In a cohort of community-living elderly men aged 65 to 95 years, age-associated changes in mental functions are more evident after the age of 85. These changes are independent of education, depression, or prevalent CEVD.  相似文献   
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The objective of this study was to determine the effectiveness of a telephone-facilitated depression care protocol in older, medically ill adults compared to routine care. A 12-week double blind randomized controlled trial was conducted in recently discharged primary care patients (N?=?124). Depression was assessed with the Patient Health Questionnaire-9. Primary care providers were notified of the level of depression severity and indications for treatment, but neither they nor the patients were contacted by a psychiatrist or other mental health professional. The primary outcome was initiation of treatment. Secondary outcomes were symptoms reduction and depression remission rates. There were no significant outcome differences between the facilitated and routine care groups. This study showed that older, medically ill adults may require a level of depression care that goes beyond a telephone-facilitated protocol.  相似文献   
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