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131.
Tobacco use, poor diet, and physical inactivity are risk behaviors established during childhood and influenced by parents. Improving health habits of rural families poses particular challenges because resources may be limited in number and reach. To characterize the kinds of prevention programs needed by rural families, 501 surveys were mailed to caregivers of elementary school children living in a rural North Carolina county. Health behaviors, related attitudes, and demographic characteristics were assessed. Risk behaviors were defined as eating less than 5 fruits and vegetables a day, exercising less than 20 minutes 3 times a week, and being a smoker. Two hundred and sixty-one adults (55%) completed the surveys. Two hundred and forty-four (93%) were female, with a mean age of 37 years, 55% had a high school or less education, 89% reported at least one risk behavior, and 57% reported 2 or more risk behaviors. Female caregivers with multiple risk behaviors had lower educational levels (p < 0.007) and placed less importance on children's health behaviors (p < 0.009) than other caregivers. Female caregivers with multiple risk behaviors were no less confident they could change their behavior than those with only one risk behavior. The majority of female caregivers of elementary school children in this rural population engaged in and modeled multiple health risk behaviors for their children. Health promotion activities that address multiple risk factors and involve children are needed by young families in rural communities.  相似文献   
132.
Intravascular brachytherapy with gamma sources has been proved to prevent in-stent restenosis in recent clinical trials. Beta sources are also being investigated. The intravascular use of radioactive sources has raised theoretical and logistic problems and renewed the interest in teletherapy for the treatment and prevention of restenosis. We review the literature published on the use of teletherapy in animal models and compare it to brachytherapy from biological and logistic points of view. Developing technologies for stereotactic radiotreatment of moving targets may offer new solutions and are being studied.  相似文献   
133.
Albunex Does Not Increase the Sensitivity of the Lung to Pulsed Ultrasound   总被引:1,自引:0,他引:1  
If cavitation in the vasculature of the lung is the physical mechanism responsible for lung hemorrhage, then addition of cavitation nuclei to the blood should enhance the bioeffect. To test the cavitation hypothesis, the extent of lung hemorrhage in mice injected with the echocontrast agent, Albunex®, was compared to lung hemorrhage in animals injected with saline. Animals were exposed for 5 minutes to 1.1-MHz pulsed ultrasound (10 μs pulse length, 100-Hz pulse repetition frequency) at a peak positive pressure at the surface of the animal of 2 MPa. This exposure is approximately twice the threshold pressure amplitude for lung hemorrhage. Lesion areas did not differ significantly in the two groups of animals and were approximately equal to the lesion area in uninjected mice from an earlier study where acoustic exposures were the same. Neither this study nor a related study of hemolysis in vivo suggests that use of Albunex in echocardiographic procedures increases the risk of bioeffects.  相似文献   
134.
We conducted a study of the 2 year cumulative incidence of trunkabnormalities in a cohort of 3,071 11 year old children (1,621boys, 1,450 girls). The following data were recorded: height,weight, signs of puberty and menarche. Trunk abnormality wasassessed in the erect child (asymmetry of shoulders and waistline,imbalance of the trunk, scoliosis, lordosis, kyphosis, swaybackand flexibility) and by the forward bending test (FBT) (ribhump or lumbar prominence, persisting scoliosis, kyphosis anddeviant lateral aspect). A normal FBT both at baseline and atfollow-up was found in 84% of the boys and in 79% of the girls.The 2 year cumulative incidence of an abnormal FBT was 10% inboys and 13% in girls.  相似文献   
135.
The protective effect of periconceptional folate on congenitalheart defects (CHDs) presented by Van Beynum et al. (2006)1contributes to the governing folate paradigm. The researchersshowed a quantitative trait effect between MTHFR 677 > CTheterozygosity and homozygosity (TT) and a modification by periconceptional  相似文献   
136.
137.
Streptokinase (SK) and tissue plasminogen activator (alteplase [tPA]) are by far the most intensively studied thrombolytic agents, but only recently a direct head-to-head comparison (GISSI-2 Trial, in which 12,490 patients have been randomized) has become available to the scientific community. This trial, with its international extension (the International tPA/SK Mortality Trial) recruited more than 20,000 patients, showed that the two drugs tested (SK and tPA) were substantially comparable as far as the clinical events were considered. ISIS-3, the largest randomized clinical trial ever performed, compares SK, tPA, and APSAC in a factorial design. Its results will be available before spring, 1991. It is likely that these two studies, if the results will be consistent, will give a definitive answer about comparison among thrombolytic drugs. As a consequence of that achievement, the interest of the scientific community will possibly be directed towards the long-term prevention of the infarct complications, namely ventricular remodeling and infarct expansion or life-threatening arrhythmias.  相似文献   
138.
A 62-year-old woman was admitted for the evaluation of pedal edema and ascitis. Echocardiography revealed a right atrial (RA) mass invading the interatrial septum and extending into the inferior vena cava (IVC). Contrast enhanced computerized tomography scan excluded extravascular involvement. An organized thrombus was diagnosed by transvenous endomyocardial biopsy. The patient was treated with continuous intravenous heparin, and died soon after from hepatic failure. Postmortem histologic examination revealed a leiomyosarcoma surrounded by a thrombus involving RA, IVC, and hepatic veins. Endomyocardial biopsy played a misleading role that affected patient's management.  相似文献   
139.
In invasive techniques such as laser angioplasty and intravascular ultrasonography, there is a source of heat inside the vascular system that is being released/dissipated by the inserted device. In this article, the transfer of heat from this source to the plaque deposited on the walls of the artery has been studied numerically using two different models. The models consider the transient conduction and the absorption of heat through the plaque. The variation of thermophysical properties is also included in the analysis. It was found that the temperature distribution depends significantly on the type of plaque and the power level.
heat transfer, arterial plaque  相似文献   
140.
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