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91.
92.
BackgroundInotropic reserve identified by dobutamine or dipyridamole stress echocardiography is associated with a better outcome in patients with idiopathic dilated cardiomyopathy (DCM), although the relative prognostic value of each remains unsettled. The purpose of the present study was to assess the relative prognostic value of dobutamine versus dipyridamole stress echocardiography for the prediction of all-cause death in patients with idiopathic DCM.Methods and ResultsEighty-seven patients (63 were male, aged 54 ± 12 years) with DCM and an ejection fraction less than 35% underwent both dipyridamole and dobutamine stress echocardiography on different days and in a random order. In all patients, wall motion score index and ejection fraction were evaluated at baseline and peak stress. All patients were followed up for an average of 52 months. All-cause death was identified as the prognostic end point. During the follow-up, 26 all-cause deaths occurred (29.8%). On multivariate analysis, either dobutamine echocardiography (relative risk 0.299; P = .02; 95% confidence interval 0.084–0.835) or dipyridamole echocardiography (relative risk 0.161; P < .00; 95% confidence interval 0.07–0.394) added significantly to a prognostic model based on clinical and resting echocardiographic variables. Survival was 83% in patients with dobutamine and 84% in patients with dipyridamole-induced contractile reserve.ConclusionsDobutamine and dipyridamole stress echocardiography have similar feasibility and prognostic accuracy in DCM risk stratification. 相似文献
93.
The primate cortex represents the external world in a distributed way, which requires for a mechanism that integrates the features of a processed event. Animal and patients studies suggest that feature binding in the visual cortex is under muscarinic-cholinergic control, whereas visuomotor integration is driven by the dopaminergic system. Consistent with this picture, we present evidence that the binding of visual and action features is modulated by spontaneous eyeblink rate (EBR), which is a functional marker of central dopaminergic function. Remarkably, the impact of EBR was restricted to the task-relevant visuomotor binding, suggesting that dopamine increased the maintenance of task-relevant information. 相似文献
94.
The primate cortex represents the external world in a distributed fashion, which calls for a mechanism that integrates and binds the features of a perceived or processed event. Animal and patients studies provide evidence that feature binding in the visual cortex is driven by the muscarinic-cholinergic system, whereas visuo-motor integration may be under dopaminergic control. Consistent with this scenario, we present indication that the binding of visual and action features is modulated by emotions through the probable stimulation of the dopaminergic system. Interestingly, the impact of emotions on binding was restricted to tasks in which shape was task-relevant, suggesting that extracting affective information is not automatic but requires attention to shape. 相似文献
95.
96.
Rationale
Chronic use of cocaine is associated with dysfunctions in frontal brain regions and dopamine D2 receptors, with poorer mental flexibility and a reduced ability to inhibit manual and attentional responses. Little is known, however, about cognitive impairments in the upcoming type of recreational cocaine polydrug user (1–4 g monthly consumption).Objective
We studied whether recreational cocaine polydrug users, who do not meet the criteria for abuse or dependence, showed impairments in working memory (WM) and cognitive flexibility.Methods
Controls and recreational cocaine polydrug users (who abstained from cocaine and other substances more than 1 week) were matched by sex, age, alcohol consumption, and IQ (Raven’s Standard Progressive Matrices). Groups were tested by using two cognitive tasks measuring cognitive flexibility and three tasks investigating the maintenance and monitoring of information in WM.Results
Recreational cocaine polydrug users performed significantly worse than controls on tasks tapping cognitive flexibility, but show comparable performance in the active maintenance and monitoring of information in WM.Conclusions
The findings suggest that recreational use of cocaine selectively impairs cognitive flexibility but not the maintenance of information in WM. The inability to adjust behavior rapidly and flexibly may have repercussions for daily life activities. 相似文献97.
Muiesan ML Salvetti M Paini A Monteduro C Galbassini G Bonzi B Poisa P Belotti E Agabiti Rosei C Rizzoni D Castellano M Agabiti Rosei E 《Hypertension》2007,49(5):1077-1083
Inappropriate left ventricular mass (LVM; ie, the value of LVM exceeding individual needs to compensate hemodynamic load) predicts the risk of cardiovascular (CV) events, independent of risk factors, either in the presence or in the absence of traditionally defined LV hypertrophy. The relation between changes in appropriateness of LVM during antihypertensive treatment and subsequent prognosis was evaluated in 436 prospectively identified uncomplicated hypertensive subjects, with a baseline and follow-up standard clinical evaluation, laboratory examinations, and echocardiogram (last examination: 6+/-3 years apart), followed for additional 4.5+/-2.5 years. The appropriateness of LVM to cardiac workload was calculated by the ratio of observed LVM to the value predicted for individual sex, height, and stroke work at rest. At baseline, low or appropriate LVM (相似文献
98.
Rizzoni D Porteri E Platto C Rizzardi N De Ciuceis C Boari GE Muiesan ML Salvetti M Zani F Miclini M Paiardi S Castellano M Rosei EA 《Journal of hypertension》2007,25(8):1698-1703
OBJECTIVES: It has been previously demonstrated that the morning rise (MoR) of blood pressure (BP) may predict major cardiovascular events in hypertensive patients. Structural alterations of small resistance arteries, as evaluated by the tunica media to internal lumen ratio (M/L) of subcutaneous small resistance arteries, may also predict cardiovascular events. Because an increased M/L may amplify the effect of hypertensive stimuli, the present study aimed to evaluate the possible relationships between MoR and M/L in a population of hypertensive patients. METHODS: Sixty-four patients with essential hypertension were included in the present study. All patients were submitted to a biopsy of subcutaneous fat. Small resistance arteries were dissected and mounted on an isometric myograph, and the M/L was measured. In addition, MoR was calculated from ambulatory blood pressure monitoring (ABPM) according to four previously published different methods (MoR1 to MoR4). RESULTS: A statistically significant correlation was observed between M/L and MoR1 (r = 0.52, P < 0.001), MoR2 (r = 0.32, P < 0.01), MoR3 (r = 0.25, P < 0.05) and MoR4 (r = 0.27, P < 0.05), as well as between internal diameter of subcutaneous small arteries and MoR1 (r = -0.45, P < 0.001) and MoR2 (r = -0.28, P < 0.05). CONCLUSION: Our results indicate that subcutaneous small artery structure is related to MoR, possibly because an altered vascular structure may amplify BP changes or, vice versa, because a greater MoR may further damage peripheral vasculature. 相似文献
99.
100.
Arosio B Segat L Milanese M Galimberti L Calabresi C Zanetti M Trabattoni D Annoni G Crovella S Vergani C 《Aging clinical and experimental research》2007,19(5):406-409
BACKGROUND AND AIMS: Peptydil prolyl cis-trans isomerase (PIN-1), which specifically regulates the conformational changes following phosphorylation of several proteins, targets the inactive hyper-phosphorylated tau on the Thr231-Pro motif and directly restores its biological function. Interestingly, PIN-1 is oxidatively inhibited not only in Alzheimer's disease brain but also in the hippocampi of mild cognitive impairment (MCI) subjects. The PIN-1 gene is characterized by two single nucleotide polymorphisms (SNPs) in the promoter region which are associated with the risk of Alzheimer's disease. The aim of this study was to analyse the genotype and allele distributions of these PIN-1 SNPs in MCI subjects diagnosed respectively as amnestic MCI (a-MCI) and multiple impaired cognitive domains (mcd-MCI) on the basis of cognitive features. METHODS: -667 T/C and -842 C/G SNPs were genotyped by polymerase chain reaction (PCR) amplification and direct sequencing in 43 MCI subjects, with the intention of comparing -667 and -842 SNP frequencies with those previously described in 111 Alzheimer's disease patients (AD) and 73 healthy controls (HC). RESULTS: The allele frequencies of the -842 C/G SNP in a-MCI subjects are similar to those of AD subjects, while those of mcd-MCI are comparable to HC (G allele 83% in both a-MCI and AD; 95% and 94% in mcd-MCI and HC, respectively). A similar trend is also observed in -842 C/G genotypes. CONCLUSIONS: Since a-MCI is thought to be the preclinical form of AD, the similar genotype distribution of -842 SNP in AD and a-MCI, but not in mcd-MCI, suggests that it is potentially involved in the conversion of a-MCI to AD. In conclusion, these findings support the theory that polymorphisms of the PIN-1 gene can affect neurodegeneration and its clinical progression. 相似文献