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1.
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   
2.
Between May 1982 and May 1988, 37 patients (28 males and 9 females, mean age 57.6, range 16–76 years) of approximately 600 evaluated for sustained ventricular tachycardia and/or fibrillation (VT/VF) were treated with an automatic implantable cardioverter defibrillator (AICD). Twenty-eight of the patients had coronary artery disease, 7 had nonischemic cardiomyopathy, 1 had amyloid hear disease, and 1 had rheumatic heart disease. The mean ejection fraction was 32.2 ± 12.9% (range, 9–64%). Eleven patients have died at a mean of 16.7 months after implantation. The cumulative survival rate was 81% at 1 year, 77% at 2 years. 68% at 3 years, and 53% at 4, 5, and 6 years. Considering only sudden deaths, the survival was 97% at 1 and 2 years, 90% at 3 years, and 80% at 4, 5, and 6 years. Twenty-one of the 37 patients received spontaneous shocks. If the first shock marks the time to death in the absence of an AICD, the cumulative survival rate would have been 56% at 1 year, 42% at 2 years, 29% at 3 years, and 14% at 4, 5, and 6 years. The maximum amount of time to a first appropriate shock was 39.7 months. Thirty-nine devices have been explanted; 28 for battery depletion; 5 for infections; 3 for improper sensing; 2 for electronic failure; and 1 at the time of cardiac transplantation. The average time to failure of the 28 units removed for battery depletion was 19.8 ±6.9 months. We conclude that in this group of patients, short-term survival is increased by AICD implantation, hut long-term survival remains poor. Incidence of sudden death is reduced to 3% at 1 and 2 years, 10% at 3 years, and 20% after 4 years. Other patient selection criteria may be useful in selecting those patients whose survival will be improved by the AICD.  相似文献   
3.
A pregnancy liaison and outreach service was developed as part of a community drug team to attract pregnant drug-dependent women into treatment. Women were provided with information on harm reduction, safer drug use and offered treatment for drug dependence. In total, 43 women (45 pregnancies) presented to the service over a 30-month period. Thirty-four women began out-patient treatment of opiate dependence. There was a significant reduction in maternal methadone dose by delivery. Of the 45 pregnancies, four women had therapeutic abortions, two first trimester and two second trimester spontaneous abortions and 34 live births (three women remained untraceable). All the pregnancies that continued to the third trimester proceeded uneventfully with a consequent live birth. Mean gestational age was 37.9 ±3.7 weeks, mean birth weight was 2863 ± 526 g, 10 of the babies were small for gestational age. Fifteen babies required medication for neonatal withdrawal symptoms; mothers whose babies exhibited withdrawal symptoms were using significantly higher doses of methadone at delivery than mothers whose babies did not withdraw. The importance of providing this type of service for women drug users in the 1990s is discussed.  相似文献   
4.
Previous studies have suggested that variations in the underlying ventricular fibrillation (VF) waveform may be one of the factors responsible for the probabilistic nature of defibrillation. The heart appeared to be more susceptible to defibrillation at higher absolute VF voltages (AVFV). This study investigated in an open-chest canine model (n = 8), a newly developed system that analyzed the VF waveform in real-time, instantaneously determined the time to shock, and immediately delivered a fixed low energy DC shock. A two parameter tracking technique using a running long-term and short-term AVFV average was devised to automatically identify a high voltage peak area of the VF waveform, which has been hypothesized to represent a critical period susceptible to defibrillation. Using a DC shock estimated at the 50% success level, the performance using this technique in 58 defibrillation trials was compared to the performance of the conventional method of shocking at a fixed time (random shock method) in 62 trials. Patch size, electrode location, and discharge voltage were kept constant while VF duration, transmyocardial resistance (TMR), energy delivered, and AVFV at the point of shock were measured. Shock energy and current, TMR, and VF duration were similar with both shock methods. A significantly higher AVFV was observed for trials performed with the peak shock method (0.66 ± 0.02 mV) as compared to trials performed with the random shock method (0.25 ± 0.09 mV) (P < 0.003). Using lead II as the only sensing lead, the success rate was increased in 6 of 8 dogs (75%) with the new method. One animal showed identical performance, and one animal a worse performance. The overall increase in success rate was 24% using a single ECG lead (range 0%-100%; P < 0.04). Our data document that using this algorithm a period of high VF voltage can be detected in realtime. The improved success in the majority of animals supports the hypothesis that a critical period susceptible to defibrillation exists during VF. However, the high AVFV detected using a single ECG lead did not translate to an improved success rate in all animals. This suggests that other factors in addition to the VF voltage measured on a single lead of the ECG are important in characterizing this critical period.  相似文献   
5.
Phenotypic analysis of lymphoproliferative disorders is now considered mandatory for accurate classification which is the basis for optimum patient management. This is presently carried out in most cases using a range of antibodies recognizing B and T-cell antigens effective in paraffin sections, and an antibody to CD3 is currently a key member of such panels, indicating T-cell phenotype. Current antibodies to CD3 are polyclonal with the inherent disadvantages of this type of reagent compared to monoclonal antibodies. In this study, we have used a recombinant fusion protein representing part of the epsilon subunit of the CD3 molecule to generate a novel monoclonal antibody (NCL-CD3-PS1) effective in paraffin sections. The antibody has been characterized biochemically and by immunohistochemistry using a wide range of normal and pathological tissues. Lineage and phenotype specificity have been supported in our study and results from other laboratories are awaited with interest.  相似文献   
6.
7.
The Preceptor-evaluation questionnaire (PEQ) was developed at the University of Mississippi Medical Center to evaluate the clinical teaching behaviour of general practice doctors in private practice who have one or more third-year medical students per year in their offices for a required general practice clerkship. The PEQ was designed to provide feedback to these doctors and the sponsoring department in an effort to improve teaching in this setting. Developed from the input of family practice doctors who have supervised students in their offices and from a review of related literature, the instrument was given to students to determine the level of importance they attributed to each teaching characteristic. A principle components factor analysis and subsequent varimax rotation produced six significant teaching factors in this setting. These six factors were:
  • 1 demonstrates a humanistic orientation toward patients and staff;
  • 2 demonstrates a humanistic orientation toward student;
  • 3 provides opportunity for practice;
  • 4 motivates and stimulates student's thinking;
  • 5 communicates effectively with student; and
  • 6 demonstrates comfort and confidence in the roles of doctor and teacher.
The factor relating to the humanistic orientation toward student has not appeared as a separate factor in other studies of clinical teaching. This may be due to the unique aspects of the relationship between student and doctor in this setting which may not occur in other settings. The PEQ and similar reliable and valid instruments can provide valuable information for the doctors in these off-campus teaching situations as well as provide useful programme planning information for the sponsoring academic departments. This information may also be valuable for off-campus residency training.  相似文献   
8.
Research suggests that young children have body image concerns, such as a desire for thinness and an avoidance of obesity. Surprisingly, few studies have investigated how children's body preferences and stereotypes are influenced by media aimed at children. In order to gain a better understanding of the content of such media, a content analysis was used to examine body image-related messages in popular children's videos and books. Results indicated that messages emphasizing the importance of physical appearance and portraying body stereotypes are present in many children's videos but relatively few books. Of the videos examined, the ones that exhibited the most body image-related messages were Cinderella and The Little Mermaid. Indian in the Cupboard and ET were the videos with the least number of body image-related messages. Of the books studied, the one with the highest number of body image-related messages was Rapunzel. Ginger and The Stinky Cheese Man were the only books studied that did not exhibit body image-related messages. Implications of an association of beauty and thinness in children's media are explored.  相似文献   
9.
This study examined body dissatisfaction (BD), drive for thinness (DT), and self-esteem in middle school students. Participants were 40 girls and 36 boys aged 11–13. Students completed BD and DT Eating Disorder Inventory subscales and the Rosenberg self-esteem questionnaire. There were no significant differences on these measures. For boys and girls, self-esteem was negatively correlated with BD, and Body Mass Index (BMI) was positively correlated with BD. For boys, BMI was positively correlated with DT. DT was negatively correlated with self-esteem in girls. The relationship between body dissatisfaction and self-esteem is cause for concern and may be a higher risk for developing eating disorders.  相似文献   
10.
The Local Atrial Deflection. Introduction : As a wave front passes unfiltered bipolar recording electrodes, the point of local depolarization is marked by a maximal change in voltage, i.e., the intrinsic deflection. However, during electrophysiologic studies, the depolarization (A) on the lead recording the His-bundle potential traditionally has been measured at the first rapid reproducible deflection on a filtered electrogram. This methodology permits considerable latitude for subjective interpretation. The purpose of this study was to assess the timing of the atrial electrogram using the intrinsic deflection of relatively unfiltered electrograms (0.1-4.0 to 1,250 Hz) or the equivalent on filtered recordings. Methods and Results : To do this we studied 70 patients without evidence of atrial or atrioventricular (AV) nodal disease, documenting the difference in timing between the A wave as traditionally measured and as measured at its peak local deflection (AL) determined from simultaneously recorded filtered and relatively unfiltered electrograms. New ranges based on the AL were established for timing of intra-atrial and AV nodal conduction intervals. The P-A (41 ± 11 msec) was significantly shorter than the P-AL (55 ± 12) and the A-H (80 ± 20) was longer than the AL-H (66 ± 21 msec), both P <0.001. Interobserver differences in measurements were smaller when using the local (AL) rather than traditional criteria. Conclusions : Conventional measurement of the A deflection provides only a rough estimate of local depolarization of the atrium near the AV node. The criteria proposed in the present article may (1) provide a better estimate of the timing of local depolarization; (2) have application in computerized timing of intervals; and (3) decrease technical problems and subjective error.  相似文献   
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