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11.
LISA HARNACK DrPH RD GLADYS BLOCK PHD AMY SUBAR PhD RD SYLVIA LANE PhD RICHARD BRAND PhD 《Journal of the American Dietetic Association》1997,97(9):957-965
Objective To examine the relationship of cancer prevention-related nutrition knowledge, beliefs, and attitudes to cancer prevention dietary behavior.Subjects/setting Noninstitutionalized US adults aged 18 years and older.Methods Data collected in the 1992 National Health Interview Survey Cancer Epidemiology Supplement were analyzed. The supplement included questions to ascertain knowledge, beliefs, and attitudes and a food frequency questionnaire to ascertain nutrient intake.Statistics Multivariate linear regression modeling was conducted to assess the hypothesized relationships.Results After adjustment for relevant covariates (age, sex, education, total energy, perceived barriers to eating a more healthful diet), knowledge and belief constructs were predictive of dietary behavior. Specifically, fat, fiber, and fruit and vegetable intakes more closely approximated dietary recommendations for persons with more cancer-prevention knowledge. The strength of the associations between these constructs and dietary behavior varied in some cases according to level of education and perceived barriers to eating a healthful diet. Of the perceived barriers to eating a healthful diet, perceived ease of eating a healthful diet was most strongly and consistently predictive of intake.Conclusions Research findings challenge dietetics practitioners to design diet- and health-promotion programs and activities that not only educate the public about the importance of diet to health, but also address barriers to dietary change. 相似文献
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Rate-Related and Autonomic Effects on Atrioventricular Conduction Assessed Through Beat-to-Beat PR Interval and Cycle Length Variability 总被引:1,自引:0,他引:1
CHRISTOPHER T. LEFFLER M.D. J. PHILIP SAUL M.D. RICHARD J. COHEN M.D. Ph .D. 《Journal of cardiovascular electrophysiology》1994,5(1):2-15
Atrioventricular Conduction Variability. Introduction: Atrioventricular AV) conduction time varies on a beat-by-beat basis in response to the influences of cardiac efferent autonomic activity and rate-dependent electrical recovery processes. The goals of this study were to distinguish these effects on AV conduction time and to compare the variability in sinoatrial and AV nodal function. Methods and Results: The PR interval on the surface ECG served as an index of AV conduction time in this study of 14 adult human subjects undergoing a random interval breathing protocol. P and R waves were located by a template-matching algorithm. Spectral analysis allowed frequency-domain comparisons between PR and RR interval variability. Spectra of PR and RR intervals had similar power distributions, although the power of the RR interval spectra was much greater. Autonomic blockade with atropine plus propranolol reduced the power of both spectra. Standing significantly decreased the spectral power from 0.15 to 0.5 Hz for PR and RR spectra, and introduced a peak near 0.1 Hz in the mean PR and RR spectra, although the latter finding was significant only for the RR interval spectra. Propranolol had no significant effects on the PR and RR interval spectra. Linear regression analysis allowed quantification of the autonomic and recovery effects on AV conduction and showed which effect predominated. Simple linear regression confirmed in adults a previous finding in children that conduction time may be either positively or negatively correlated with cycle length. By multiple regression and transfer function analysis, the inverse relation seen in some subjects was attributed to the effect of recovery from the preceding cycle. With the preceding recovery period accounted for, the conduction time and cycle length of the current beat were positively correlated, presumably due to the parallel autonomic effects on the sinoatrial and AV nodes. The magnitude of the recovery effect predicted by the regression analysis was similar to published values. Conclusion: A noninvasive evaluation of the surface ECG can be used to compare variability in AV conduction time and cycle length and characterize the effects of autonomic efferent activity and rate-related recovery on AV nodal function. 相似文献
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Developmental Toxicology Studies of Vancomycin Hydrochloride Administered Intravenously to Rats and Rabbits 总被引:1,自引:0,他引:1
Pregnant CD rats were given vancomycin intravenously in dosesof 0, 40, 120, or 200 mg/kg on Gestation Days (GD) 615;pregnant New Zealand white rabbits were given 0, 40, 80, or120 mg/kg intravenously on GD 618. Cesarean sectionswere performed on rats and rabbits on GD 20 and 28, respectively.In rats, maternal toxicity was indicated in the 120- and 200-mg/kgtreatment groups by cortical tubular nephrosis. Maternal bodyweight gain and food consumption and fetal viability, weight,and morphology were not adversely affected by vancomycin. Maternaland developmental no observed adverse effect levels (NOAELs)in the rat were 40 and 200 mg/kg, respectively. In rabbits,maternal toxicity was indicated by cortical tubular nephrosisin the 80- and 120-mg/kg treatment groups; a single death anddepression of body weight gain and food consumption occurredin the 120-mg/kg treatment group. Developmental toxicity wasindicated by depression of fetal weight in the 120-mg/kg treatmentgroup; fetal viability and morphology were not adversely affectedby vancomycin. Maternal and developmental NOAELs in the rabbitwere 40 and 80 mg/kg, respectively. Based on these data, vancomycindid not exhibit selective toxicity toward the developing rator rabbit conceptus. 相似文献
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Flecainide 总被引:1,自引:0,他引:1
RODNEY H. FALK M.D. RICHARD I. FOGEL M.D. 《Journal of cardiovascular electrophysiology》1994,5(11):964-981
Flecainide. Flecainide is a Class IC antiarrhythmic agent whose primary electrophysiologic effect is a slowing of conduction in a wide range of cardiac tissues. It is well absorbed and effective in suppressing isolated premature ventricular contractions (PVCs) or nonsustained ventricular arrhythmia but has only a modest efficacy when electrophysiologic testing is used as an endpoint. Us adverse effect on mortality in the CAST trial suggested a propensity to proarrhythmia-a phenomenon to which the Class IC agents appear particularly prone. Despite the applicability of the CAST study only to patients with a prior myocardial infarction, there has been a shift away from flecainide in ventricular arrhythmia, but the low noncardiac side effect profile of the agent allows for its continued use in a wide variety of supraventricular arrhythmias. ( J Cardiovasc Electrophysiol, Vol. 5, pp. 964–981. November 1994 ) 相似文献
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Growing awareness of the potential benefits of advanced medicine, emerging democracies, growing middle classes and an ageing population world-wide are significant forces shaping future demand for world-class health care. Coupled with an increased awareness of the potential benefits of advanced modern medical technologies, these factors will have a dramatic impact on medical education systems. Traditional academic institutions might not represent the optimal approach to education in the 21st century. They are expensive to build and run, typically reward academic excellence not exceptional health care delivery, teach matriculating students on site, and tend to perpetuate themselves. The expertise of centres of excellence needs to be disseminated more widely, to a 'student' or client base interacting with the institution only episodically. As relevant geographic distances increase, access to such centres becomes more difficult. To attack this problem on a global basis, we must be able to teach and interact at a distance. Telemedicine is likely to form an essential part of the solution. 相似文献
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RICHARD G. LEA JENNY UNDERWOOD KATHY C. FLANDERS HAL HIRTE DALJEET BANWATT SUZETTA FINOTTO ISAO OHNO SALIM DAYA CALVIN HARLEY MAGDY MICHEL JAMES F. MOWBRAY DAVID A. CLARK 《American journal of reproductive immunology (New York, N.Y. : 1989)》1995,34(1):52-64
PROBLEM : To determine if patients with unexplained recurrent miscarriage have a deficiency of decidual immunosuppressor cells that produce transforming growth factor β type 2, as has been found in mice with abortion due to rejection and/or trophoblast failure. METHODS : Decidual biopsy specimens were taken as near to the placental attachment site as possible under ultrasound guidance from first trimester legal termination (control) patients with recurrent miscarriage and non-viable pregnancy, and from patients with sporadic missed abortion. The tissue was tested for TGFβ-2+ suppressor cells by in situ hybridization, immunohistochemistry, and analysis of supernatants. RESULTS : TGFβ-2-related suppressor molecules similar but not identical to those identified in pregnant mice were released by decidual lymphoid cells. Fifty percent of 14 recurrent miscarriage patients showed a lack of suppressor cells and 59% were subnormal in comparison to 20 controls and 5 sporadic miscarriage patients, where 80–85% of the patients had detectable suppressor cells. CONCLUSIONS : Suppressor cell deficiency is compatible with a role for rejection and/or trophoblast failure in some patients with recurrent miscarriage. Presence of suppressor cells in most patients with missed abortion (4/5) is compatible with an alternative cause of fetal death, similar to findings reported in genetic fetal death mice. 相似文献