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At least 217 records · Page 12Linked to original sources

PubMed1991

Fluid intake during an ultramarathon running race: relationship to plasma volume and serum sodium and potassium.

To assess the relationship between self-selected fluid intake patterns and changes in plasma volume and serum electrolytes during prolonged exercise, five men completed ultramarathon runs ranging from 50 to 100 km. There was a significant relationship between fluid intake and plasma volume changes but no changes occurred in either serum sodium or potassium. Subjects who ingested the most fluid during the race had a modest hemodilution without any changes in serum or potassium. This response may have been influenced by the consumption of beverages containing osmotically active solutes such as sodium and glucose.

Exercise↗

PubMed1991

Decreases in resting plasma beta-endorphin and depression scores after endurance training.

That endurance training changes resting plasma beta-endorphin (BE) at the same time that there are improvements in non-clinical depression was tested in medically healthy middle-aged men (40-60 years). Subjects were self-selected based on compliance into treatment (T, n = 10) and placebo (P, n = 6) groups. T attended an eight month fitness program. P had less than 50% attendance in the program. Treadmill tests at the pre and post program were used to estimate the Physical Fitness Score (PFS). The Minnesota Multiphasic Personality Inventory (MMPI) was used to measure depression. All psychological scores were within non-pathological, normal limits. BE was measured with the subjects fasting and resting in the early morning. BE, detected by radioimmunoassay, decreased (p less than .005) from pre 48.53 +/- 3.32 (SE) to post 31.73 +/- 4.43 pg/ml in T. The MMPI depression score also decreased in T (p less than .05) from pre 58.90 +/- 2.81 (SE) to post 53.20 +/- 1.48 T-score units. In contrast, the PFS increased in T (p less than .005) from pre 254.57 +/- 18.62 (SE) to post 304.94 +/- 15.95 PFS units. No pre to post program changes were detected in P. In conclusion, endurance training of eight months duration appeared to decrease the resting plasma BE concentrations and the MMPI depression scores of the middle-aged men in the present study.

Depression↗

PubMed1991

A clinical trial of the American Heart Association step one diet for treatment of hypercholesterolemia.

BACKGROUND: Although diet therapy is the primary treatment for hypercholesterolemia, a trial to determine the effectiveness of the new American Heart Association Step One Diet (AHA diet) in lowering cholesterol has to our knowledge never been carried out. METHODS: A clinical trial was conducted to assess the plasma lipids response and adherence to the AHA diet in 120 men and women with hypercholesterolemia. All subjects were advised to follow the AHA diet for 18 weeks. RESULTS: After 6 weeks of the AHA diet intervention, there were modest but significant reductions in plasma total cholesterol (-2.6%) and low-density lipoprotein (LDL) cholesterol (-3.5%), but no further significant reductions were observed thereafter. Rather, there was a tendency to return to and even exceed baseline levels of total cholesterol and LDL cholesterol over the subsequent 12 weeks, in spite of the subjects' reported continued adherence to the AHA diet and maintenance of weight loss throughout the entire study period. Nevertheless, 51% of the subjects had experienced improvement (-0.2% to -26.3%) in their plasma LDL cholesterol levels by the end of the study. CONCLUSIONS: A probable reason for the limited response of the diet was low baseline levels in intake of saturated fat and cholesterol by participants. The subjects who were older and had higher levels of plasma LDL cholesterol and total fat intake at baseline experienced better plasma LDL cholesterol response to the AHA diet. Thus, practicing physicians should consider assessing the baseline dietary fat and cholesterol intake of patients with hypercholesterolemia before starting the AHA diet, since patients may already be following a relatively prudent self-selected diet. Additional dietary gains in lipid management might well require a more severe restriction of dietary fats and cholesterol. Long-term efficacy of the AHA diet should also be evaluated clinically with periodic lipid profiles.

Adult↗

PubMed1991

The interrelation of urinary calcium and sodium intake in healthy elderly Japanese.

To evaluate whether habitual excess sodium intake is significant as a risk factor for calcium loss in elderly Japanese, a relationship between calcium excretion and sodium excretion was studied in 39 male and 44 female Japanese, aged 60 and over. They are healthy, free-living and consuming a self-selected diet. A significant positive correlation between urinary calcium excretion and sodium excretion per 24-hour was observed both in males (r = .415, p less than 0.01) and in females (r = .330, p less than 0.05). The relationship was still significant even after adjustment for sex, age, body mass index, alkaline phosphatase levels and protein as well as calcium and phosphorus intake. It was estimated that the increase in urinary calcium excretion was about 1.0 mmol/day per 100 mmol increase in urinary sodium excretion.

Aged↗

PubMedDate not supplied

The energy expenditure index: a method to quantitate and compare walking energy expenditure for children and adolescents.

We used heart rate and walking speed to calculate an energy expenditure index (EEI), the ratio of heart rate per meter walked, for 102 normal subjects, age 6-18 years. Heart rate was measured at self-selected slow, comfortable, and fast walking speeds on the floor and on a motor-driven treadmill. At slow walking speeds (37 +/- 10 m/min) the EEI was elevated (0.71 +/- 0.32 beats/m), indicating poor economy. At comfortable speeds (70 +/- 11 m/min) the EEI values decreased to the maximum economy (0.47 +/- 0.13 beats/m). At fast speeds (101 +/- 13 m/min), the EEI increased (0.61 +/- 0.17 beats/m), indicating poor economy relative to comfortable speeds. A graph of the EEI versus walking speed provides a way to evaluate and compare energy expenditure in a clinical setting.

Adolescent↗

PubMed1991

[Cardiovascular risk factors of visitors to a mass-screening booth].

The attitude towards mass screening of serum cholesterol is controversial. In order to characterize the volunteers of such screenings and to test the representativity of its findings, we compared the data of 1686 adult health-screening participants collected during a trade fair in the city of Basel, Switzerland, with the results of two population-based studies, the Basel City Risk Factor Survey and the MONICA Project in Western Switzerland. Among those screened, there was an over-representation of women and older persons. The age-specific medians of blood cholesterol and proportions of hypercholesterolemic persons were consistently higher in female screenees--and marginally so in males--than in the reference populations, whereas higher proportions of persons with ideal cholesterol level in those screened were also observed, especially in younger males. Higher systolic blood pressure, lower relative body weight and less regular smoking were found consistently among the screenees. This cross-sectional study shows that the participants of such mass screening actions are a selective group of older, more frequently female health-conscious persons with a specific risk-factor pattern. Mass screenings of self-selected volunteers can, therefore, not be used for a reliable prediction of risk-factor distributions in the general population. Moreover, suggested further steps for those screenees with both health-conscious behavior and elevated biological risk-factor levels, such as second measurement, medical consultation and counselling, cannot be assured in the setting of a trade fair. The objectives and intentions of such mass screening activities should be reconsidered and discussed.

Adult↗

PubMed1991

An American clinic for traditional Chinese medicine: comparisons to family medicine and chiropractic.

Patient self-selection delimits the kinds of disorders treated by practitioners of acupuncture and other traditional Chinese modalities in the United States. Based upon a questionnaire administered to 200 first-time patients in a teaching clinic for traditional Chinese medicine (TCM) in California, it was determined that practitioners of TCM attract patients whose health problems would also be appropriate for management by family physicians, chiropractors or mental health professionals. Approximately one-third of presenting complaints can be categorized as presumed organic disorders (many of which may have been medical treatment failures); one-third comprise musculoskeletal problems and headaches; and one-third appear to be psychological or psychosomatic in nature.

Acupuncture Therapy↗

PubMed1991

Medical audit: a Well Woman Clinic in the Royal Naval training practice, Gibraltar.

In order to assess the effectiveness of patient self-selection, and the value of dedicating surgery time to a specific clinic, attendances at a Well Woman Clinic were compared with attendances for the same reasons at other times. During the nine month audit period the opportunity was also taken to overhaul the Age/Sex Register, and assess the uptake of Cervical Screening at the Garrison Medical Centre. This unit is part of the Royal Naval Training Practice in Gibraltar.

Ambulatory Care Facilities↗

PubMed1991

The substance-abusing family: consideration for nursing research.

Investigations to explore and document the characteristics of addicted families are possible for nurse researchers in a variety of settings. Addicted families can be identified through hospitals, clinics, or community substance abuse treatment centers. Confidentiality issues must be addressed with carefully designed consent forms. A thorough understanding of addicted family systems is essential. System, role, and family theories provide a framework for understanding the influence of substance abuse on all family members. Anticipation of common social, economic, and criminal crises of addicted families will assist the researcher to avoid conflicts between research and service. Methodological limitations are common in research with addicted families, but well-designed, descriptive studies with small- to moderate-sized self-selected samples can add greatly to our nursing knowledge base over time.

Confidentiality↗

PubMed1991

Work and power in gait of stroke patients.

Biomechanical analysis of the work and power patterns involved in gait provides insight into the nature of gait deficits and suggests methods for improvement. The purpose of this study was to describe the work and power characteristics during gait for both limbs of hemiplegic patients, and to determine the work and power variables related to self-selected speeds of walking. The gait of 30 ambulatory adults between the ages of 47 and 79 years was studied using two-dimensional cinematography and force-plate data in a link-segment model. About 40% of the positive work required for walking was performed by the muscles of the affected side. Major contributors were the ankle plantar flexors, hip flexors, and hip extensors. The results suggest interdependence between the limbs and between muscle groups of the same limb; a need for further research is indicated.

Aged↗

PubMed1991

Idiopathic gastroparesis is associated with a multiplicity of severe dietary deficiencies.

UNLABELLED: Idiopathic gastroparesis (IG), a disorder characterized by abnormally delayed emptying of food from the stomach, is associated with many symptoms that could have an impact on dietary intake. The intake of dietary protein, carbohydrate, fat, fiber, vitamins, and minerals was prospectively evaluated in patients with symptomatic IG and compared with asymptomatic controls. Twenty-four patients and 24 age- and sex-matched controls completed a detailed 7-day diet record while consuming a self-selected diet. Dietary information was entered into a computer and analyzed using the Nutranal program. Results were expressed as daily intake and percent recommended dietary allowance (%RDA) when applicable. Patients consumed a diet containing fewer calories than would have been predicted based on age, height, sex, frame, and weight (85% of calculated energy expenditure vs 100%) for controls. Although patients with IG consumed significantly fewer calories than controls (1112 kcal vs 1431 kcal), the proportion of fat (32% vs 34%), carbohydrate (49% vs 48%), and protein (17% vs 16%) was similar in the two groups. Intake of vitamins B6, vitamin C, folate, niacin, riboflavin, thiamine, calcium, copper, iron, magnesium, phosphorus, and zinc were below the %RDA. Intake of vitamin B12, vitamin C, folate, thiamine, niacin, magnesium, phosphorus, and zinc were significantly less than controls. Vitamin A intake was above the RDA and not different from that of controls. Prolonged t1/2 of solids correlated with diminished intake of protein, iron, niacin, and potassium. They correlated inversely with serum albumin in patients with idiopathic gastroparesis. CONCLUSION: Although eating less, patients with IG do not consistently alter the proportion of fat, carbohydrate, and protein in their diets. Because their diet is markedly deficient in a number of essential vitamins and minerals, dietary evaluation and counseling is suggested for all patients with idiopathic gastroparesis.

Adult↗

PubMed1991

Relationships of anxiety scores to screening and training status of air traffic controllers.

The present study assessed the relationship between anxiety, as measured by the State-Trait Personality Inventory (STPI), and success of post-strike air traffic control specialist (ATCS) trainees at the FAA Academy and during field training. The STPI was administered to students who entered the FAA Academy between June 1984 and September 1985. Academy test scores were obtained for 1,790 students in the en route option. Criterion data included the field training status of the Academy graduates as of July 1988. Statistical analyses determined the relationships between ATCS student scores on the STPI measures and a) normative data and b) Academy screening and field training results. ATCS students reported significantly lower state (current level) and trait (proneness) levels of anxiety than did either college students or military recruits. Trainees who had relatively high scores (for ATCSs) on a combined index of the trait and state measures of anxiety exhibited significantly higher a) percentages of Academy failures/withdrawals, b) percentages of option switches in the field, and c) overall field attrition, than did trainees with low scores. Results support the operation of some personality-related self-selection among ATCS applicants regarding anxiety and the importance of this low anxiety characteristic for ATCS job success.

Aerospace Medicine↗

PubMed1991

Segmental contributions to total body momentum in sit-to-stand.

In a previous investigation, we reported that the maximum linear momentum of the body center of mass (CM) during a sit-to-stand task showed a relative invariance in the horizontal vs the vertical direction of motion as the speed of ascent increased from natural to fast. The present study investigated the segmental origin of this directionally specific difference by examining the linear momentum of the shank, thigh, and head-arm-trunk segments for ten healthy young adults at slow, natural, and fast self-selected speeds. Findings indicated that the head-arm-trunk was the major contributor to the horizontal maximum linear momentum of the CM and accounted for the relative invariance in its magnitude. In contrast, the thigh was the major contributor to the vertical maximum linear momentum of the CM and was responsible for the progressive increase in its magnitude across the range of speeds. Moreover, the compatibility between the motions of the head-arm-trunk and of the shank in their general profile and peak magnitudes further suggested that a simplifying strategy may have been employed to reduce the overall number of degrees of freedom associated with the sit-to-stand movement.

Adult↗

PubMed1978

Update of naltrexone treatment.

To summarize, then, our work with naltrexone in a multi-modality treatment program indicates that it appeals to about 5-10 percent of narcotic addicts--those who conciously want to obtain drug-free status. It does significantly attentuate the effect of narcotics to the extent that they lose their reinforcing properties, and it has minimal side effects. Although we treated a self-selected population, it is noteworthy that about 10 percent of those who remained on naltrexone for more than a week were still opiate free 6 months after cessation of treatment. For some it appeared to be a turning point in their lives. It was the first time in years that they could live in their neighborhood and not be either intoxicated or occupied with the pursuit of narcotics. Our behavioral studies have identified a number of conditioned psychophysiological responses associated with the self-injection ritual. So far, although we have succeeded in extinguishing some of these responses, this has not resulted in an improved clinical outcome. We are currently working on more comprehensive behavioral treatments, but the clinical significance of these conditioned responses is uncertain at present.

Adult↗

PubMed1979

Potential effect of demographic and other variables in studies comparing morbidity of breast-fed and bottle-fed infants.

Comparing the morbidity of breast-fed and bottle-fed infants is confounded by inherent differences in breast-feeding and bottle-feeding mothers and their infants. Self-selection introduces complex variables encompassing much more than milk source used for infant feeding. Reasons for selecting breast or bottle feeding relate to demographic, socioeconomic, educational, ethnic, cultural, and psychological factors, as well as maternal and infant physical and emotional health. Many of the differences in the maternal populations may affect infant care practices, access to medical care, and infant health status. Studies published to date have not quantified these confounding effects and other potential biases in comparing morbidity to breast- and bottle-fed infants and the relationship between milk source and incidence of infantile disease remains in question. There is need for more cautious use of the available data and investigators must seek ways to design future studies to take into account the differences between breast-feeding and bottle-feeding mothers that affect both reported and actual infant morbidity.

Bottle Feeding↗

PubMedDate not supplied

[Treatment of the sick elderly in households accommodating several generations].

Multigenerational households with widowed persons aged 70 and more have been studied in order to determine the relationship between the following two groups of variables: (a) variables in the aged person describing the existence and degree of an organic mental impairment due to a dementive process and of other signs of physical illnesses. (b) variables in her daughter or daughter in law consisting of selfratings of psychosomatic complaints and of attitude-scales. Results were as follows: (a) If there were indications of personality changes due to an organic brain syndrom the relatives had a lower degree of life-satisfaction and more frequently suffered from psychosomatic symptoms and interpersonal stress than those, whose old relatives showed an unaltered personality. (b) A great number of comparisons failed to show any statistical differences. Especially severe physical illness, organic brain syndrome and the need for physical care were not related to life satisfaction, psychosomatic complaints, stress due to emotional involvement and the attitude towards home-care. Our attempt to explain the missing correlations led to the following factors: the small size of the sample, self-selection of the sample and possibly inappropriate operationalisation and measurement of variables. In respect to these results the ongoing study will be modified in some details: There will be a qualitative analysis of transcribed semi-structured interviews. The proportion of families with severely demented relatives will be increased. In an additional step we shall examine families, who have decided to transfer their old member into an institution.

Aged↗

PubMed1978

The effect of energy and nitrogen intake upon urea production in children with uremia and undernutrition.

Children with severe uremia who had anorexia were observed in a clinical study center where dietary energy and nitrogen intake could be compared with urea nitrogen production (UNPr). The children received a supplement of dextrose and amino acids at night, ate a self-selected diet and were encouraged to use carbohydrate supplements. Energy intake varied from 22 to 110 kcal/kg/day and nitrogen intake from 105 to 323 mg/kg/day. UNPr was reciprocally related to energy intake. Nitrogen intake minus UNPr, an index of nitrogen balance, was positively related to energy intake. UNPr was not related to nitrogen intake. Nitrogen intake (NI) and NI-UNPr were correlated and the slope of the regression was 1.15. We inferred from the data that low energy intakes (less than 60 kcal/kg/day) were associated with catabolic losses of body protein. Intakes above that level were associated with a low and stable rate of UNPr. The level of energy and nitrogen intake within the range observed limited the rate of nitrogen retention. Once maintenance requirements for energy and nitrogen were satisfied, the efficiency with which nitrogen was used for net protein synthesis was very high.

Adolescent↗

PubMed1979

Gastric secretory and humoral responses to anticipated feeding in five men.

It is believed that humans anticipate appetizing meals by increasing vagally mediated gastric acid secretion. Studies were conducted on 5 normal male volunteers to characterize further the secretory response to anticipated meals. Plasma gastrin and glucose levels were monitored to assess the possibility that these humoral factors participated in the observed secretory changes. Subjects were not fed for 22 hr and were intubated at 10 AM. Basal gastric collections were begun, and at 1 PM on different days, subjects either (a) selected meals of choice prepared in their presence for 1 hr before nasogastric tube withdrawal and meal ingestion or (b) were not food-teased or fed. Gastric collections were obtained every 10 min during the "test" hour (1-2 PM) during both (a) and (b) studies and titrated for gastric acid. Blood samples for plasma glucose and RIA gastrin were obtained during basal and test hours every 10 min. Pentagastrin-stimulated maximal acid output studies were conducted on all subjects on separate days. Results showed a progressive and statistically significant rise in gastric acid secretion when an appetizing, self-selected meal was anticipated. The magnitude of this rise was 55% of the mean pentagastrin-induced acid response. This acid response did not correlate with changes in plasma glucose or gastrin. The study demonstrated that pure psychic stimulation may be as effective an acid stimulant as sham feeding.

Adult↗