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81.
BACKGROUND: By 2016, the proportion of Canadians older than 65 years of age will increase to 16%, and there will be an increase in the absolute number of cases of cardiovascular disease in older Canadians. The Canadian Heart Health Surveys database provides information about this population upon which health policy related to cardiovascular disease can be based. This paper presents for the first time population-based data on the risk factors for cardiovascular disease in older Canadians. METHODS: Canadians from all 10 provinces participated in surveys of cardiovascular risk factors; health insurance registries were used as sampling frames. In each province, probability samples of 2200 adults 18 to 74 years old not living in institutions, on reserves or in military camps were asked to participate in interviews and to undergo testing at clinics for major risk factors for cardiovascular disease. RESULTS: A total of 2739 men (response rate 70%) and 2617 women (response rate 66%) aged 55 to 74 years participated in the survey and also provided follow-up clinical measurements at the clinic. Overall, 52% of participants were hypertensive, 26% had isolated systolic hypertension, and 30% had a total blood cholesterol level of 6.2 mmol/L or greater. Rates of current smoking were lower in women than men (17% v. 22%). Overall, 87% of men and 78% of women who were current smokers smoked at least 10 cigarettes per day. Only slightly more than half of participants exercised at least once a week for at least 15 minutes, and almost half had a body mass index of 27 or greater. In only 4% was no major risk factor for cardiovascular disease detected. INTERPRETATION: Significant numbers of older Canadians have one or more major risk factors for cardiovascular disease. Many of these risk factors are amenable to modification.  相似文献   
82.
Current synthetic vascular prostheses do not acquire lining of vascular endothelium in humans or dogs. Endothelial seeding of vascular grafts has been proposed as a means of reducing the thrombogenicity of these grafts. We examined feasibility of cultivating endothelial cells (EC) by tissue culture technique and their subsequent seeding onto small diameter polytetra fluoroethylene (PTFE) grafts. Twenty adult dogs underwent common carotid artery interposition with 4 mm PTFE grafts. Ten dogs received seeded and the remaining ten received unseeded grafts. Grafts were removed at 4 and 12 weeks and their gross/morphological features compared. Cumulative patency rates for seeded grafts were 70% as compared to unseeded ones 30%. Seeded grafts were completely surfaced with a mono-layer of endothelium by 4 weeks. Small graft patency appears to be related to the establishment of an endothelial surface, the development of which is clearly facilitated by seeding with autogenous endothelium.KEY WORDS: Endothelial cell seeding, Vascular grafts  相似文献   
83.
Aim: The aim of this study was to evaluate the long-term results of resective surgery on children with difficult-to-treat epilepsy in Norway. Methods: In the period 1995–2004, 64 surgical procedures (54 resections and 10 functional hemispherotomies) were performed in 54 children. The children’s medical records were retrospectively reviewed at a minimum of 2 years after surgery. We sent a questionnaire regarding their epilepsy (seizures, usage of antiepileptic drugs) and general functioning (social situation, motor, language, cognition, behavioural or emotional problems, any remedial action) to the children/parents after a mean follow-up period of 7 years. Results: 55.5% of the children were seizure-free. The success rate varied according to the type of surgery. Best results were found after functional hemispherotomies and temporal lobe resections, as nine of 10 (90%) and 10 of 19 (53%) of these patients, respectively, became seizure-free. In addition to a better seizure control, 71% of the children/parents reported of a better cognitive and psychosocial functioning. Conclusion: The results of epilepsy surgery in this paediatric cohort are very edifying, and it is our impression that this treatment option is underused in Norway.  相似文献   
84.
A 12‐year‐old child presented with recurrent respiratory infections and was diagnosed with Scimitar syndrome. Drainage of IVC and course of aberrant arterial supply from aorta were not clear by echocardiogram, and hence, additional imaging was planned. CT unraveled the presence of a rare combination of anomalous pulmonary venous connection (APVC) to IVC, with near‐atresia/severe stenosis of IVC, superior to the drainage of scimitar vein. There was a prominent azygos vein with preferential contrast opacification on lower limb injection.  相似文献   
85.
Digital beam attenuator technique for compensated chest radiography   总被引:1,自引:0,他引:1  
The feasibility of producing patient-specific beam attenuators for chest radiography has been investigated using an anthropomorphic phantom and a human volunteer. A low-dose test exposure is digitized, processed, and used to print a small cerium filter, which is placed in the x-ray beam near the collimator. The final radiograph is recorded on film. The technique results in relatively uniform film exposure, so that structures in all regions of the chest are simultaneously displayed with optimal film contrast. The equalized exposure improves image quality in the normally underpenetrated regions and reduces the role of cross-scatter from the lungs. The image is analogous to optical or computer-processed unsharp masking techniques, but the processing is accomplished in the x-ray beam and results in an improved exposure distribution, giving advantages that cannot be achieved with image processing techniques alone.  相似文献   
86.
Color Doppler flow imaging or compression ultrasound (US) was used to prospectively determine frequency of thrombosis at 54 venous insertion sites (47 in common femoral veins, seven in right internal jugular veins) after percutaneous placement of Greenfield filters for interruption of the inferior vena cava. Fifty-one filters were successfully placed in 51 patients with a dilator set or a balloon angioplasty catheter. Nine focal thrombi were detected in the common femoral vein (19%) and one in the right internal jugular vein (14%). Use of dilators induced eight thrombi (24%), compared with two (10%) from balloon catheters. The left common femoral vein had a high frequency of thrombosis, regardless of dilation technique (five of nine). Of nine patients with acute common femoral vein thrombosis, four became symptomatic within 10 days after the procedure. Patients may remain asymptomatic or have delayed symptoms; thus, US is valuable for determining patients at risk of thrombosis of the common femoral vein.  相似文献   
87.
Hospital and dental charts of 2,693 patients in whom total prosthetic joints had been placed at the Veterans Administration Hospitals of Ann Arbor and Allen Park, Michigan, as well as at The University of Michigan Hospital, were analyzed. Of the thirty (1.1%) late prosthetic joint infections (greater than 6 months after placement), only one (0.04%) could be temporally associated with dental treatment. A Fisher's exact test of the data reflected that dental treatment in this population did not increase the incidence of late prosthetic joint infections (p value is 0.0005). Nine of the thirty late infections occurred in insulin-dependent diabetic patients and patients on long-term immunosuppressive therapy. An analysis of the organisms isolated from the late infections shows that 54% where Staphylococcus epidermidis and Staphylococcus aureus. These data do not support the practice of prescribing prophylactic antibiotic coverage of prosthetic hip and knee joints prior to all dental therapy. Rather, use of antibiotics during dental treatment appears warranted only if a chronic bacteremia is anticipated or where a predisposing systemic condition may exist.  相似文献   
88.
Two alkaloids from Heimia salicifolia, cryogenine and nesodine, were respectively 2.48 and 2.24 times as potent as aspirin as inhibitors of prostaglandin synthetase prepared from bovine seminal vesicles. Reference compounds, indomethacin and phenylbutazone, were respectively 2800 and 8.75 times as potent while a synthetic analogue of cryogenine, JB-1-0, was 0.656 times the potency of aspirin. This activity may help to explain the traditional medicine use of H. salicifolia in the Americas.  相似文献   
89.
Sympatric populations of white-tailed deer and mule deer (Odocoileus virginianus and Odocoileus hemionus, respectively) on a west Texas ranch share a common mitochondrial DNA restriction map genotype. Phylogenetic analysis indicates that this genotype is more characteristic of O. virginianus than of O. hemionus. The genotype of west Texas deer differs from that of O. virginianus from South Carolina by five mutational events (1.3% sequence divergence), whereas it differs from that of O. hemionus from California by 17 events (5.5% divergence). We suggest that interspecies hybridization has occurred, primarily between mule deer bucks and white-tailed deer does, with preferential absorption of hybrid offspring into the mule deer gene pool. Introgressive hybridization may be involved in ongoing displacement of mule deer by white-tailed deer in west Texas.  相似文献   
90.
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