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11.
Objective: Severe atherosclerosis of the ascending aorta and arch frequently causes difficulties during heart operations, hindering surgical manoeuvres and potentially leading to systemic embolism. The aim of our study was to assess the safety and effectiveness of replacing the atherosclerotic ascending aorta in this setting. Methods: Aortic atherosclerosis was characterized by epiaortic ultrasonographic scanning in 90.1% of 1927 consecutive adult patients undergoing cardiac operations, and by computed tomographic chest scanning in selected cases. Thirty-six of the 152 patients requiring major derangements from our standard practice due to aortic atherosclerosis underwent replacement of the ascending aorta and constitute the study group. Replacement of the aorta was extended to the arch in 13 cases (36.1%). It was associated with single or multiple valve surgery in 34 patients (94.4%) and with coronary revascularization in 30 (83.3%). Two patients (5.6%) underwent coronary bypass grafting without valve surgery. A cryoablation procedure was associated in three patients with permanent atrial fibrillation. Deep hypothermic circulatory arrest was employed in 34 patients (94.4%), while proximal aortic disease allowed conventional distal crossclamping in 2 cases. The risk of operative mortality was estimated by the logistic EuroSCORE both with and withholding the variable ‘surgery of the thoracic aorta’. All survivors were followed-up for 1–41 months (16 ± 12). Results: Two patients died in the hospital (5.6%) and two during follow-up, for a cumulative survival of 91.3% and 85.6% at 1 and 3 years, respectively (hospital deaths included). The hospital death rate compared favourably with the expected estimates of 25.5% (p < 0.05) and 10.3% (p = 0.67) obtained by the EuroSCORE full model and without ‘aortic surgery’, respectively. In-hospital adverse neurologic events occurred in six patients (16.7%), including stroke in one patient (2.8%) and neurocognitive disturbances in five (13.9%), although they were all transient and cleared before discharge. Excess bleeding required re-exploration in four patients (11.1%), and one more patient underwent emergency grafting for acute postoperative coronary occlusion. Ten patients (38.5%) were intubated for longer than 24 h. Conclusion: Despite significant perioperative morbidity, replacement of the severely atherosclerotic aorta is worth consideration to avert expectedly higher death and stroke rates.  相似文献   
12.
Long-term oral anticoagulation requires careful patient monitoring in order to optimize results and to limit hemorrhagic or thromboembolic complications of treatment. For this reason, any improvement in anticoagulant control and management can be expected to have far-reaching consequences in extending longevity and decreasing complications in anticoagulated patients after heart valve surgery. Because one attractive means of improving anticoagulant management is to give patients a share of the responsibility, a program was designed to encourage patients to take an active role in monitoring their own prothrombin time (PT) and managing their own oral anticoagulation. During the period from August 1986 to February 1992, 600 patients requiring long-term anticoagulation, mainly after heart valve replacement, were trained to measure their own PT at the Cardiac Rehabilitation Center (Herz-Krauslauf-Klinik, Bad Berleburg, Germany) and to manage their own therapy: 216 patients could be followed with regard to their self-determined prothrombin times. The results were within the target range in 83.1% of the PT determinations (n=12,306 measurements) taken by the patients themselves. Neither major bleeding nor thromboembolic complications were observed in 205 patient-years of self-monitoring of PT and self-management of oral anticoagulation.  相似文献   
13.
14.
Summary Quantitative studies were made of the distribution of labeled intracortical axons after focal injections of horseradish peroxidase (HRP) into mouse barrel cortex, in vitro. The pattern of labeled fibers was compared to that of labeled cell bodies with respect to the barrel map in layer IV. We analyzed 4 cortices with injections in supragranular layers and centered above a single barrel row. Computer microscope/image analysis routines were used to collect the data and to perform various statistical analyses on them. The distributions of both labeled cells and fibers in layer IV and in the infragranular layers show strong connectional tendencies between barrels representing a whisker row. This result is consistent with single unit recordings from barrel cortex. Fiber labeling is more widespread than cell body labeling in layer IV. In addition, the fibers show a directional bias into the adjacent anterior barrel row (e.g., C D, D E). In earlier 2-deoxyglucose (2-DG) studies of behaving animals, the anterior barrel rows were more heavily labeled; inter-row projections are therefore predominantly from less active to more active barrel columns. These data show that labeled fiber distribution differs from the distribution pattern of labeled cell bodies. The findings indicate that integration of information between whisker rows within barrel cortex involves asymmetrical connections within layer IV and infragranular layers.  相似文献   
15.
Between 1965 and 1986 we saw 36 children with enuresis and urinary tract infection in association with “inversion” of facial expression when laughing. Urologic work-up of these patients disclosed characteristic findings of mild neuropathic bladder in all cases, with severe urinary tract damage in most of them. The clear association of distortion in facial expression and neuropathic bladder with resultant damage to the genitourinary tract should prompt urological evaluation of individuals with “inversion” of facial expression. About two thirds of the patients also had moderate to severe constipation. We suggest the term urofacial syndrome for this disorder. The occurrence of the disorder in multiple sibs, normal parents, increased parental consanguinity, and equal sex ratio indicate autosomal recessive inheritance.  相似文献   
16.
Various studies have evaluated the possible role of the -1438G/A polymorphism within the 5-HT2A receptor gene in the susceptibility to Eating Disorders (EDs). One hundred and forty-eight ED patients (EDp) and 89 control subjects were interviewed by means of the Eating Disorder Examination (EDE) and analyzed for distribution of the -1438G/A polymorphism. Patients with the AA genotype suffering from Anorexia Nervosa and Bulimia Nervosa showed higher Weight and Shape Concern (P = 0.003 and P = 0.010, respectively) scores and greater overall severity of the ED psychopathology (EDE total score) (P = 0.012). The obtained preliminary data suggest the use of dimensional psychopathological measures in ED genetic studies.  相似文献   
17.
OBJECTIVES: To investigate whether infection with human T-lymphotropic virus type 1 (HTLV-1) increases the risk of tuberculosis. DESIGN: A case-control study. SETTING: City of Salvador, Brazil. PARTICIPANTS: A total of 375 patients with tuberculosis (cases) and 378 individuals without tuberculosis (controls), matched by age and sex. MAIN OUTCOME MEASURE: Tuberculosis of lung or lymph node. MAIN EXPOSURE: Human HTLV-1 infection. RESULTS: The prevalence of HTLV-1 infection was 4.27% (16/375) in patients with tuberculosis and 1.32% (5/378) in controls, resulting in a crude odds ratio of 3.31 (95% CI, 1.20-9.13) and an adjusted odds ratio of 3.01 (95% CI, 1.06-8.58). CONCLUSION: HTLV-1 infection is associated with a first diagnosis of tuberculosis. This may have implications for tuberculosis control in places with high prevalence of HTLV-1.  相似文献   
18.
BACKGROUND: People with Down's syndrome (DS) show early Alzheimer-like dementia. It has been suggested that the pro-inflammatory cytokine class plays a role in Alzheimer's disease (AD). The study aims at verifying whether pro-inflammatory cytokines in DS are correlated with age, affective symptoms and intellectual decline to a different degree than in subjects with non-DS learning disabilities. METHODS: Cases: 19 subjects with DS; controls: sex- and age-matched individuals with learning disabilities caused by perinatal ischaemic damage. The level of mental retardation was assessed according to DSM-IV; psychopathological symptoms were measured by the Assessment and Information Rating Profile. Serum levels of cytokines were determined with ELISA. RESULTS: DS patients showed higher levels of cytokines and chemokines, with the exception of RANTES; but the only significant difference detected was for MIP-1alpha. A correlation between the degree of mental retardation and IL-6, and between MIP-lalpha and age was found in patients with DS, but not in controls. CONCLUSIONS: The data obtained suggest a possible involvement of chemokines in the inflammatory and degenerative processes similar to AD in DS. Further longitudinal research is required to confirm these findings.  相似文献   
19.
Simultaneous measurements of skin potential (SP) and skin resistance (SR) obtained from 20 male and 20 female adult subjects during 2 sessions held 2 to 9 days apart were used in studying (1) the correlation of change measurements and prestimulus level in the two measures, and (2) the amount of correlation between SP and SR using both simple difference and residual change scores in which the regression of poststimulus values on initial level (prestimulus) has been controlled. Correlations within Ss and correlations among Ss showed large individual variability, correlation differences between males and females, and high correlation between SP and SR change scores. Although the law of initial value (LIV) seemed to have little applicability to the measurement of electrodermal responses, the results underscored the need to control for contamination of change measures by initial level regardless of direction.  相似文献   
20.
Patients infected with HIV-1 develop a potent humoral immune response against the virus, but HIV-1 primary isolates are remarkably resistant to neutralizing antibodies. Considering that the envelope glycoprotein of HIV-1 (gp120/41) is heavily glycosylated, we investigated whether anti-carbohydrate antibodies could inhibit HIV-1 infection in vitro. We studied the neutralizing activity of three monoclonal antibodies (mAbs) raised to carbohydrates of Schistosoma mansoni, against seven primary isolates of HIV-1. Assays were performed infecting peripheral blood mononuclear cells from normal donors with viral isolates previously treated with mAbs. Viral strains used were tropic for the coreceptors CCR5, CXCR4, and dual-tropic ones. We found that the anti-glycan mAbs vigorously inhibited HIV-1 infection, regardless of the preferential coreceptor usage of the isolate, in a dose-response manner. Importantly, five isolates were resistant to neutralization by two HIV-1 antibody-positive human sera endowed with potent anti-HIV-1 inhibitory activity. Our findings suggest that carbohydrates of the HIV-1 viral envelope may be a target of an effective humoral immune response elicited by vaccination.The first two authors contributed equally to this work  相似文献   
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