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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   

2.
Toxic pustuloderma associated with azithromycin   总被引:1,自引:0,他引:1  
  相似文献   
3.
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   
4.
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   
9.
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   
10.

Background

At the present time, 50 to 60% of the population above 70 years of age suffers from a hearing impairment and from 0.6 to 1.1% has a severe to profound loss, which cannot benefit from an hearing aid. Moreover, it is expected that this prevalence will grow by more than two-fold in the next 40 years. There is strong evidence that hearing loss in older adults is associated with both cognitive load and social isolation, which in turn, are associated with cognitive and physical functioning. Cochlear implant (CI) dramatically improves sound audibility and speech understanding. The aim of this paper was to analyze outcome and complications of CI treatment in elderly patients.

Methods

A retrospective study on 17 patients, aged at implantation between 65 and 79 years (mean = 70.47 ± 3.94), unilaterally implanted for severe to profound bilateral hearing loss. The following data were statistically evaluated: pre-implant pure-tone threshold and tests of speech recognition, both with hearing aid that without; post-implant threshold and speech perception with CI off and on. Moreover, statistical correlations of PTA improvement between two age groups (65 to 70 and over 70 years) were carried out.

Results

Mean PTA improved from 111.25 (± 17.51) (pre-implant) to 43.81 (± 9.27) (post-implant); and the mean SRT improved from 90 dB to 65 dB. Moreover there was no statistical difference in PTA improvement between the two age groups (65 to 70 and over 70 years). No severe per- or post-operative surgical complications were noted.

Discussion

In the elderly, CI is a safe procedure that significantly improves hearing threshold (p < 0.00001) and speech perception (p < 0.01). Support of family and professionals, as well as duration of deafness and pre-implant scores greatly influence the results of rehabilitation and its perceived benefit. CI should not be denied in older individuals who are otherwise in good health.
  相似文献   
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