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At least 577 records · Page 32Linked to original sources
PubMed2005

Changes in physical activity explain paradoxical relationship between baseline physical activity and adiposity changes in adolescent girls: the FLVS II study.

OBJECTIVE: To investigate in adolescents relationships between habitual physical activity (PA) and changes in several indicators of adiposity. DESIGN: Longitudinal population-based study. The Fleurbaix-Laventie Ville Sante II (FLVS II) study in Northern France. SUBJECTS: A total of 222 boys and 214 girls aged 8-18 y, not obese at inclusion. MEASUREMENTS: PA (Modifiable Activity Questionnaire) and adiposity (body mass index (kg/m2), percent body fat by bioimpedance analysis, sum of four skinfolds, waist circumference) were assessed in 1999 and 2001. Adiposity indicators adjusted for age and pubertal stage were compared between groups of baseline PA and between groups of PA changes, separately by sex. RESULTS: At baseline, PA was not associated with adiposity indicators in both sexes. In girls only, being in the group with the highest age-relative level of moderate PA at baseline predicted the highest adiposity gain from baseline to follow-up, for all indicators. After adjustment for baseline values, all adiposity indicators were higher at follow-up in girls who had decreased their relative level of moderate PA during follow-up. In boys, changes in adiposity during follow-up were not significantly different across groups of PA changes. However, the sum of skinfolds at follow-up, adjusted for baseline value, tended to be higher in those who decreased their vigorous PA level and lower in those who increased it. CONCLUSION: In adolescent girls, a decrease in PA rather than inactivity per se may result in increased adiposity over time.

Adipose Tissue↗
PubMed1994

Effect of alcohol and risk of physical harm on human physical aggression.

Forty male undergraduate students ingested either a high dose of alcohol or a placebo and were provided with feedback regarding their risk of receiving electric shock from an opponent in a competitive reaction-time situation. Intoxicated subjects (blood concentration of 96mg/dL) responded more aggressively than did the sober subjects on measures of physical aggression. Results indicated that the feedback manipulation had no effect on the aggressive responses of the intoxicated subjects. The findings are discussed in terms of current cognitive models of alcohol-related aggression.

Adolescent↗
PubMed2002

Perceptions of the physical environment, stage of change for physical activity, and walking among Australian adults.

Data for this study were from a population survey of 1,200 adults ages 40-60 years, sampled from the Illawarra region of New South Wales. Questionnaire items on perceptions of the environment were factor analyzed into: Aesthetic Environment and Practical Environment. For both factors, those in the Contemplation stage had more negative views of the environment than those in Maintenance. Those who walked for 0-20 min/week held more negative perceptions of their environment than those who walked for 21-120 min/week and those who walked for > 120 min/week. The health promotion implications of these findings are that environments perceived as attractive and as providing convenient access to services and facilities may influence motivational readiness for physical activity and time spent walking.

Adult↗
PubMed1971

Biological, physical, and chemical properties of Eastern equine encephalitis virus. I. Purification and physical properties.

A new purification procedure was adopted for Eastern equine encephalitis virus which does not subject the virus to pelleting at any stage. Three- to 4-liter volumes were passed through a diethylaminoethyl cellulose column. The virus-containing fractions were banded on a sucrose cushion and finally concentrated in an isopycnic band in a linear sucrose gradient. This method reduced the volume 1,000-fold with a concomitant increase in viral titer, i.e., better than 90% recovery. Numerous criteria have been used to establish that this viral preparation was essentially free from cellular debris and nonviral material. Physical studies on this purified viral product were initiated. The sedimentation coefficient as determined by band sedimentation was 240S, the buoyant density in sucrose was 1.18 g/cc, and the diameter of the virus was 54 nm. From the diameter and the buoyant density it was possible to calculate the molecular weight of a spherical particle. In this case, the calculated molecular weight for Eastern equine encephalitis virus was 58 x 10(6) daltons.

Amino Acids↗
PubMed2006

Do children from an inner city British school meet the recommended levels of physical activity? Results from a cross sectional survey using objective measurements of physical activity.

Questionnaire surveys suggest physical activity levels in children are low, particularly among children from deprived areas. Using accelerometers, it was found that children from a deprived inner city school were active at recommended levels and had similar levels of activity to children in other studies from more affluent populations. However, this finding was dependent on the threshold used to define moderate activity.

Child↗
PubMed1994

The AAPM/RSNA physics tutorial for residents. Basic physics of MR imaging: an introduction.

This article provides an introduction to the basic physical principles of magnetic resonance (MR) imaging. Essential basic concepts such as nuclear magnetism, tissue magnetization, precession, excitation, and tissue relaxation properties are presented. Hydrogen spin density and tissue relaxation times T1, T2, and T2* are explained. The basic elements of a planar MR pulse sequence are described: section selection during tissue excitation, phase encoding, and frequency encoding during signal measurement.

Magnetic Resonance Imaging↗
PubMed1989

Family background and physical health of adolescents admitted to an inpatient psychiatric unit, II: Physical health.

The charts of 100 adolescents admitted to a special unit of a provincial psychiatric hospital were reviewed. These patients primarily had a conduct disorder (71.6% of boys and 77.5% of girls) or an affective disorder (6.6% of boys, 15.0% of girls). There was a higher incidence of congenital disorders in the population than expected, suggesting that such disorders may predispose to psychological troubles later in life. Convulsions also occurred more often in this population. Most patients (78.3% of boys and 85.0% of girls) had one or more medical diagnoses. Several potentially serious findings (anemia, pregnancy, hepatomegaly, thyroiditis) were first noted on the admission physical examination. Patients with conduct disorder had certain health problems that are likely to be the result of the psychiatric disorder, such as liver function changes in drug and alcohol abusers and abnormal Pap smears in sexually active girls with multiple partners. If these medical conditions are not followed and treated, they have the potential for causing serious problems at a later date. These findings point out the continued need for the expertise of psychiatrists and other physicians in children's mental health facilities.

Adolescent↗
PubMed2000

Effects of physical training on the recovery of the autonomic nervous activity during exercise after coronary artery bypass grafting: effects of physical training after CABG.

Analysis of heart rate variability (HRV) can identify patients at risk of sudden cardiac death after myocardial infarction. The present study examined the effect of 2 weeks of supervised aerobic exercise training on the recovery of the autonomic nervous activity, exercise capacity, and cardiac output (CO) after coronary artery bypass grafting (CABG). Twenty-eight patients were randomly divided into the training group or the control group and performed exercise tests at 1 week, 3 weeks, 3 months, 6 months and 1 year after CABG. The HRV was measured, and the high-frequency component of HRV was used as an index of parasympathetic nerve activity (PNA); the plasma norepinephrine concentration (NE) was used as an index of sympathetic nervous activity. Cardiac output was also measured. In the training group, peak VO2, peak CO and PNA during exercise had improved at 3 weeks, but there was no improvement in these indices in the control group. NE decreased 1 week after CABG in both groups. These results indicate that physical training soon after CABG improves not only the exercise capacity, but also PNA.

Aged↗
PubMed1998

The effect of one night's sleep deprivation on temperature, mood, and physical performance in subjects with different amounts of habitual physical activity.

Eleven healthy males were studied twice. On one occasion (control, C), they slept (night 1) and then underwent a battery of tests at 4 h intervals from 06:00 day 1 to 02:00 day 2; then, after a normal sleep (night 2), they were tested from 10:00 to 22:00 on day 2. On the second occasion (sleep deprivation, SD), the subjects remained awake during night 1. Each battery of tests consisted of measurements of tympanic membrane temperature, profile of mood states (POMS), muscle strength, self-chosen work rate (SCWR), perceived exertion, and heart rate (HR) while exercising on a stationary cycle ergometer. Subjects also kept a diary of their activities during the two days and answered a questionnaire about their habitual physical activity. Results showed a significant negative effect of sleep deprivation on most mood states on day 1, but no effect on the other variables. By day 2, mood had tended to recover, though muscle strength tended to be worse in both control and sleep-deprivation experiments. There was also a more general tendency for negative effects to be present at the end of day 1 (02:00) or at the beginning of day 2 (10:00). There was limited support for the view that subjects who were habitually more active showed less negative effects after sleep deprivation and responded less adversely to the poor sleep achieved on the university premises (night 2). These results stress the considerable interindividual variation in the responses to sleep loss and, therefore, the difficulty associated with giving general advice to individuals about work or training capability after sleep loss.

Adult↗
PubMed1998

[A survey on the physical growth of children under 7 years in the urban and suburban rural areas of nine cities of China in 1995. Coordinating Group of Nine Cities on Physical Growth and Development of Children].

OBJECTIVE: To know the changing trend of physical growth of Chinese children and compare their nutritional status with that of ten years ago. METHODS: Random cluster sampling was used and 157,362 healthly children were classified into 22 groups according to location (urban and rural), sex(boy and girl), and age (0-7 years). RESULTS: As compared with the results in 1985, the mean weight, height and sitting height were significantly increased. The chest and head circumference in most age groups were slightly improved. The urban-rural difference in weight and height reduced. The children in northern and central china were heavier and taller than those in southern China though the regional gap is narrowing in this respect. CONCLUSION: The condition of growth and nutrition of children 0-7 years from urban and suburban rural areas has been much improved. The growth speed of rural children has caught up or surpassed that of their urban peers.

Body Height↗
PubMed2002

[Effect of superhigh frequency electromagnetic fields and physical exercise on physical performance and extrasystole in myocardial ischemia patients with stable angina pectoris].

AIM: To study impact of UHF electromagnetic fields in combination with bicycle exercise on muscular performance (MP) and extrasystole (ES) in IHD patients with stable angina of functional class 1 and 2 (SA). MATERIAL AND METHODS: The trial included 112 IHD patients with SA and ES. 36 of them were exposed to coursed electromagnetic fields (40 W, on heart area). The other 42 patients received the same treatment and exercised on bicycle ergometer. 34 patients received placebo procedures and did therapeutic exercises. The effect was assessed with spiroveloergometry and ECG Holter ambulatory monitoring. RESULTS: It was found that 40 W UHF electromagnetic fields in combination with exercise on veloergometer exert a training effect in IHD patients with extrasystole manifesting with higher physical performance and coronary heart reserve. The antiarrhythmic effect consisted in a significant daily fall in mean ventricular ES number by 48.2%, supraventricular EX by 54.8%. CONCLUSION: Combined application of 40 W UHF electromagnetic fields on heart area with bicycle exercise is effective in IHD patients with ES.

Angina Pectoris↗
PubMedDate not supplied

[The impact of regular physical activity on physical and mental health: how motivate the patient?].

A sedentary lifestyle is associated with the development of numerous diseases and seems to increase in western societies. The influence of a regular physical activity in the prevention of cardiovascular diseases, diabetes, obesity, cancers, anxious and depressive disturbances is summarized. Potential mechanisms of its positive influence are discussed and prescription recommendations are made.

Exercise↗
PubMed1989

Requirement for delivery of signals by physical interaction and soluble factors from accessory cells in the induction of receptor-mediated T cell proliferation. Effectiveness of IFN-gamma modulation of accessory cells for physical interaction with T cells.

We analyzed the mechanism by which accessory cells support the induction of the proliferation of human peripheral blood T cells by a monoclonal anti-CD3 antibody, OKT3. Cross-linking of T cell receptor/CD3 complex by anti-CD3 coupled to latex beads and the addition of IL-1 are not enough to induce the IL-2 production and proliferation of T cells extensively depleted of accessory cells, while the addition of both the culture supernatant of macrophages or a monoblastic cell line, U937 cells, and the paraformaldehyde-fixed macrophages or U937 cells which had been precultured with interferon-gamma before fixation into the culture of the T cells with anti-CD3-latex did induce the T cell proliferation. Lack of the addition of either one of these did not induce the response. These results indicate that the signal(s) delivered by soluble factors released from the accessory cells and that delivered by the physical interaction between accessory cells and T cells are both required for the induction of IL 2 production and proliferation of T cells by anti-CD3-latex. Importantly, the macrophages or U937 cells had to be cultured with Con A-stimulated lymphocyte culture supernatant or IFN-gamma prior to fixation with paraformaldehyde, suggesting that a molecule(s) inducible on accessory cells surface by IFN-gamma or other lymphokine is necessary for the effective accessory cell-T cell interaction to induce the T cell response. It was further revealed that the activity of the culture supernatant of accessory cells may be mediated synergistically by IL 1 and a certain other factor(s) and was actually shown to be replaced by the combined addition of rIL-1 and rIL-6 but not by rIL-1 alone. The experimental system described here will be very useful for dissecting the accessory functions for T cell activation.

Adjuvants, Immunologic↗
PubMed1993

[Arterial pressure, physical activity and physical work capacity].

A representative population sample was studied to elucidate relationships of arterial pressure (AR) with muscular performance (MP) and arterial hypertension risk factors. Power working capacity (PWCx) was measured by means of exercise tolerance test at rest, under physical loading and after the exercise. The findings were processed using a multivariate step-by-step regression analysis which established independent relations between exercise and postexercise MP and arterial hypertension. In normal and hypertensive males a rise in systolic pressure (SP) after the initial exercise (load 1) was dependent on PWC1 after more intensive exercise (load 2) on relations of MP with heart rate, SP and diastolic pressure (DP). In hypertensive males the SP elevation depended also on the age, B. W. index and heart rate. In normal AP males a DP rise depended on PWC2 and MP, the increment being limited by relationships between MP, DP, heart rate and SP. In hypertensive males the influence of PWC1 is defined through a SP rise after load 1. In normal AP and hypertensive females PWC1 is decisive for a SP rise. In normal AP females growth of DP after load 2 was dependent on PWC2 in relation to heart rate growth after load 2, while in hypertensive females PWC1 resulted in DP elevation after load 1. On comparison of the groups with normal and high AP the degree of AP increment under exercise depended on the relations of MP with heart rate, SP and DP.

Adult↗