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1.
Background. Partial harvesting of the left internal mammary artery (LIMA) is a widespread technique used during minimally invasive coronary operations performed through a left anterior small thoracotomy. The influence of persisting LIMA branches was investigated to evaluate their effect on the blood flow of the left anterior descending artery.

Methods. Thirty patients, 15 with totally (group A) and 15 with partially (group B) harvested LIMAs, were evaluated. All the patients underwent postoperative angiography, during which a flow map of the LIMA was performed. The average peak velocity and the diastolic-to-systolic peak velocity ratio were recorded. The LIMA graft flow pattern was recorded in the proximal and distal thirds of the artery. Intramammary adenosine (12 to 14 μg) was injected and the average peak velocities before and after injection were calculated.

Results. The average peak velocity was similar in both groups in the proximal and distal thirds of the LIMA (25 ± 7 and 26 ± 5 cm/sec, respectively, in group A versus 27 ± 5 and 25 ± 5 cm/sec, respectively in group B; p = NS). The diastolic-to-systolic peak velocity ratio was similar proximally (0.78 ± 0.3 in group A versus 0.69 ± 0.3 cm/s in group B; p = NS), but not distally (1.72 ± 0.1 in group A versus 0.97 ± 0.3 in group B; p < 0.0005). The LIMA graft flow reserve was similar both proximally and distally (2.6 ± 0.6 and 2.5 ± 0.3 cm/s, respectively, in group A versus 2.6 ± 0.5 and 2.6 ± 0.3 cm/s, respectively, in group B; p = NS).

Conclusions. The persistence of LIMA branches does not influence the blood flow of the left anterior descending artery after acute adenosine-induced myocardial hyperemia. If a left anterior small thoracotomy is used in left anterior descending artery direct revascularization, complete LIMA harvesting is not mandatory and depends on the personal preference of the surgeon.  相似文献   

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The role of adrenergic mechanism in the pathogenesis of allergic disease is controversial. Recent experimental and clinical reports have suggested that -adrenergic blockade impairs and stimulation enhances extrarenal potassium uptake in humans. This led us to study the effect of the intravenous administration of salbutamol, a specific -2-adrenergic agonist, on serum potassium in 9 healthy subjects and in 23 patients with allergic asthma and/or rhinitis. Serum potassium fell significantly and reached a peak decline at the end of venous infusion in all the normal subjects. Seventeen atopic subjects showed a lower or absent serum K+ decrement: there was no difference between asthmatic and rhinitic patients. There was no relation among the salbutamol-induced serum potassium decrement, serum glucose increment, blood pressure and heart-rate changes, and nonspecific bronchial reactivity. These findings suggest that -2-adrenergic hyporesponsiveness is present only in some allergic patients.  相似文献   
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The cerebral representation of space depends on the integration of many different sensory inputs. The vestibular system provides one such input and its dysfunction can cause profound spatial disorientation. Using positron emission tomography (PET), we measured regional cerebral perfusion with various vestibular stimulations to map central vestibular projections and to investigate the cerebral basis of spatial disorientation. We showed that the temporoparietal cortex, the insula, the putamen, and the anterior cingulate cortex are the cerebral projections of the vestibular system in man and that the spatial disorientation caused by unilateral vestibular stimulation is associated with their asymmetric activation.  相似文献   
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Summary In order to investigate the prevalence of vectorcardiographic bites, expression of small areas of fibrosis, atrophy or degeneration of the myocardium, we studied, using the vectorcardiograms (VCG) of 101 diabetic patients (35 with insulin-dependent and 66 with non-insulin-dependent diabetes mellitus, aged from 25 to 60 years, without hypertension, coronary artery disease, or intraventricular conduction defects) and 228 normal control subjects, matched for age and sex. The prevalence of bites was 38.6% in diabetic patients and 10.0% in the control group (p<0.001). Diabetic patients were also subdivided into groups according to age, sex, metabolic control, risk factors for coronary heart disease, type of diabetes, duration of diabetes and diabetic microangiopathy. No correlation was found between any of the variables investigated nor of a combination of these, and the presence of bites. We conclude that VCG is a sensitive test for cardiac involvement in diabetic patients but that it cannot be used to identify any specific factor able to influence the onset and evolution of this involvement.  相似文献   
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In this study we report the long-term follow-up of EA, a patient originally affected by a disproportionate semantic impairment of biological categories due to herpetic encephalitis. After 10 years, EA still presented a biological categories semantic impairment, but his deficit had become minimal for animals while it remained considerably severe for fruit and vegetables, without any evolution from the original level of impairment. The eventual discrepancy between the two subsets of biological categories was statistically significant at word–picture matching and verbal semantic probes (and could not be explained by nuisance variables), but not significant at picture naming due to an associated lexical impairment that, besides plant life items, also affected animals and artefact stimuli.

Our recovery data corroborate the notion that biological categories should be further fractionated, and we comment on the suitability of different accounts of category specificity to accommodate such findings. We discuss our case against the background of other cases reported in the literature and the current models of organisation of the semantic system, bringing to light some interesting consistencies concerning patients whose semantic impairment disproportionately affects the categories of fruit and vegetables.  相似文献   
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We examined the hypothesis that the attention/executive deficits in mild cognitive impairment (MCI) due to Alzheimer’s disease is associated to an abnormal cortical activation, revealed by the method of event-related synchronization/desynchronization (ERS/ERD) in the theta band during a paradigm of temporal orienting of attention. MCI patients (n = 25) and healthy elderly (HE) matched controls (n = 15) performed a task in which periodically omitted tones had to be predicted and their virtual onset time had to be marked by pressing a button. Single-trial theta responses were measured, respectively, before and after the motor response. Then, theta responses were compared to theta power during eyes closed resting state (ERD/ERS method).The temporal course of the task was characterized by two different behavioural conditions: (1) a pre-event epoch, in which the subject awaited the virtual onset of the omitted tone, (2) a post-event (after button pressing) epoch, in which the subject was in a post-motor response condition. The most important findings are summarized as follows: (1) in both groups, the pre-event epoch was characterized by theta ERS on temporal electrodes, but HE had a greater theta ERS compared to that of MCI group; (2) in both groups, during the post-motor condition, there was a theta ERS on prefrontal regions, and, also in this case, HE showed a greater theta enhancement compared to that of MCI patients; (3) HE showed evidence of lateralization: during the waiting epoch, theta ERS was dominant on the right posterior temporal lead (T6), whilst, during the post-motor epoch, theta ERS was greater on the left, as well as the midline prefrontal leads. Compared to the traditional neuropsychological measures for the episodic memory, these theta ERS indicators were less accurate in differentiating MCI patients from healthy elderly. The clinical relevance of these findings is that the weaker theta reactivity in MCI would indicate an early impairment in the temporal orienting of attention in the early stage of the clinical course of this neurodegenerative disease.  相似文献   
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Appropriate management of hyperglycemia is crucial for patients with type 2 diabetes. Aim of the FADOI-DIAMOND study was to evaluate real-world management of type 2 diabetic patients hospitalized in Internal Medicine wards (IMW) and the effects of a standardized educational intervention for IMW staff. DIAMOND has been carried out in 53 Italian IMW, with two cross-sectional surveys interspersed with an educational program (PRE phase and POST phase). In PRE phase, each center reviewed the charts of the last 30 hospitalized patients with known type 2 diabetes. An educational program was conducted in each center by means of the “outreach visit,” a face-to-face meeting between IMW staff and a trained external expert. Six months after, each center repeated the data collection (POST phase), specular to the PRE. A total of 3,167 patients were enrolled (1,588 PRE and 1,579 POST). From PRE phase to POST, patients with registered anthropometric data (54.1 vs. 74.9 %, p < 0.001) and in-hospital/recent measurement of glycated hemoglobin (48.2 vs. 61.4 %, p < 0.005) increased significantly. After educational program, more patients received insulin during hospitalization (68.3 vs. 63.6 %, p = 0.005). A more relevant variation in glycemia during hospitalization was observed in POST phase than PRE (?22.2 vs. ?15.5 mg/dL, p < 0.001), without differences as for occurrence of hypoglycemia (12.3 vs. 11.9 %). A one-shot educational intervention led to persistent improvement in the management of hospitalized patients with type 2 diabetes and to significant better glycemic control. Further studies might evaluate the effectiveness of a more aggressive educational program, on both management and outcomes.  相似文献   
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