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At least 667 records · Page 37Linked to original sources
PubMed1989

[Economic substantiation of intensifying the activities of pediatric surgical departments].

The article calculates the economical efficacy and averted economical loss in intensive work of a pediatric surgical department. The introduction of a complex of therapeutic and preventive measures producing a purposeful effect on the wound process made it possible to reduce postoperative complications to 0.3% and the general hospital stay to 3.0 days in a group of patients with "minor" surgical diseases and to hospitalize additionally at least 900 patients annually. More than 203,000 roubles are saved annually due to a shorter stay in the hospital and increased bed turnover.

Child↗
PubMed1989

Human immunodeficiency virus and mental health: meeting the needs of health professionals.

Psychiatric-mental health nurses are taking a leadership role in the human immunodeficiency virus epidemic. This article details activities, developed through federally-supported acquired immune deficiency syndrome (AIDS) projects, which are designed to meet the mental health needs of health professionals who work intensively with people with AIDS.

Acquired Immunodeficiency Syndrome↗
PubMed1989

[The integrative cardiorespiratory exercise test].

The cardiorespiratory incremental maximal exercise test is being used increasingly for clinical evaluation. It is based on the fact that during physical effort the output of the cardiovascular and respiratory systems increase to maintain a higher metabolic rate and stroke volume. Cardiac output increases by increase in both heart rate and stroke volume. Ventilation increases by increase in respiratory rate and tidal volume. All changes are synchronous, so that blood composition and gas partial pressures are constant over a wide range of work intensities. The response of a normal sedentary subject to incremental exercise is presented, as well as the improvement in an athlete's physical performance as a result of training. An obese subject, despite normal maximal oxygen uptake, felt compromised due to the high energy cost of moving his heavy torso. The large normal breathing reserve during exercise was demonstrated in 2 subjects who, despite lung disease, responded normally to the test. It is likely that this test will be widely used for evaluation of patients with heart and lung disease.

Exercise Test↗
PubMed1989

Work capacity, exercise responses and body composition of professional pilots in relation to age.

Body composition and submaximal and maximal cardiorespiratory responses during a progressive upright bicycle ergometer test were measured in 410 professional male pilots, aged 20 to 68 years, and divided into four groups (30, 39, 49, and 59 years). Fat-free weight by hydrostatic weighing was not significantly different between groups and fat increased linearly with age, while height was lower and weight levelled off in the oldest group. Aerobic work capacity (VO2max) fell at a rate of 0.25 ml.min-1.kg-1 per year in this unique population of healthy, but generally sedentary men. A subgroup of 10 pilots, tested annually from age 31 to 47, demonstrated a reversal of the age-related decline in VO2max. This was attributable to regular physical activity, short of athletic training, and changes in personal health habits stimulated by self-assessment available from the repeated tests incorporated into the medical prevention program. These data considered in relation to more recent reports of stroke volume during similar maximal exercise protocols suggest that VO2max is limited during aging by a reduction in tissue diffusing capacity or increased maldistribution of perfusion in relation to O2 uptake in muscle and this can be partially prevented by training. Reference standards for heart rate, blood pressure and ventilation during submaximal and maximal exercise levels are presented in relation to energy requirements and work intensity at various ages.

Adult↗
PubMed1985

Exercise and endorphins--male responses.

The discovery of the endogenous opiates in the mid-1970's has led to a tremendous scientific effort attempting to determine the physiological role of these peptides. An increase in the peripheral plasma levels of beta-endorphin in humans after exercise has been noted by all investigators to date. This indication that the endogenous opiate system is activated during exercise should stimulate investigators to use exercise and training as models to aid in the understanding of these peptides. Unlike most other endocrines, plasma levels of beta-endorphin do not increase proportionally to work intensity. This conclusion is based on only one study and requires corroboration. All human studies to date have used radioimmunoassays, with one exception, and interestingly that study showed no consistent change in plasma levels of leucine enkephalin-like radioreceptor assayable ligands. In males, essentially no information is available concerning the effects of training on either acute or chronic responses to exercise. Studies using opiate antagonists (receptor type-specific) in human and animal models should prove useful in establishing or disproving roles for these peptides in appetite, pain perception, temperature regulation, metabolism, ventilation, and blood pressure control during exercise.

Animals↗
PubMedDate not supplied

[Physiological and hygienic basis for the rational nutrition of female workers in branches of light industry].

The energy expenditures in the nonproductive period in the women-workers of the boot and shoe industry (group I) and the sewing industry (group II) were almost similar: in group I it was on an average 1372 +/- 35.4 kcal, in group II--1384 +/- 27.6 kcal. In the productive period the energy expenditures in the workers of group I fluctuated from 1.56 to 2.09 kcal/min, in those of group II--from 1.78 to 2.27 kcal/min. Summary energy expenditures in the productive period comprised 877 +/- 91.1 kcal (in group I), and 949 +/- 51.1 kcal (in group II). Daily energy expenditures were 2249 +/- 77.1 kcal and 2333 +/- 63.9 kcal, respectively. The energy value of the rations of their actual nutrition insignificantly exceeded their energy expenditures (on an average by 120-150 kcal) due to excessive fat consumption, animal fat, in particular. Their rations were characterized by protein, and, to a lesser extent, carbohydrate deficiency, by imbalanced mineral composition and vitamin A, B1, B2, PP and C deficiency. Microsymptoms of vitamin deficiency (mainly those of vitamin C deficiency) were detected in 64% of the examined subjects, excessive weight was found in 23-26% and obesity in 11-16% of the women. The women working at the modern boot and shoe and sewing industry should be referred to the first category of the work intensity, with respect to the energy requirements and the energy value of the nutrient components of their food rations.

Adolescent↗
PubMedDate not supplied

The medical record and the medical interview: an evaluation of student case histories.

This study assessed the results of a second-year family medicine course designed to improve student abilities in writing complete assessments and plans from interviews with standardized patients. Sixty-six students attended lectures on the patient's perception of the symptoms of the major causes of death, learned techniques of medical interviewing, saw a model interview by their tutor, received model faculty histories based on American Board of Family Practice Office Record Review Criteria, and received critiques of their own histories. Students in the highest decile recorded twice as much information as those in the lowest decile and recorded as many history items as the faculty member who recorded the most history items. The faculty, however, recorded a more complete list of diagnoses, differential diagnoses, and investigations. Students in the lowest decile recorded the least information and the least number of assessments and plans and did not respond to written critiques. Students in the lowest decile could improve if they were identified early in the course and worked intensively with role models.

Curriculum↗
PubMed1986

Reduced exercise time in competitive simulations consequent to low level ozone exposure.

Ten highly trained endurance athletes were studied to determine the effects of exposure to low ozone (O3) concentrations on simulated competitive endurance performance and associated physiological and subjective symptom responses. Each subject was randomly exposed to filtered air (FA), and to 0.12, 0.18, and 0.24 ppm O3 while performing a 1 h competitive simulation protocol on a bicycle ergometer. Endurance performance was evaluated by the number of subjects unable to complete rides (last 30 min at an intense work load of approximately 86% VO2max). All subjects completed the FA exposure, whereas one, five, and seven subjects did not complete the 0.12, 0.18, and 0.24 ppm O3 exposures, respectively. Statistical analysis indicated a significant (P less than 0.05) increase in the inability of subjects to complete the competitive simulations with increasing O3 concentration, including a significant difference between the 0.24 ppm O3 and FA exposure. Significant decreases (P less than 0.05) were also observed following the 0.18 and 0.24 ppm O3 exposures, respectively, in forced vital capacity (-7.8 and -9.9%), and forced expiratory volume in 1 s (-5.8 and -10.5%). No significant O3 effect was observed for exercise respiratory metabolism or ventilatory pattern responses. However, the number of reported subjective symptoms increased significantly following the 0.18 and 0.24 ppm O3 protocols. These data demonstrate significant decrements in simulated competitive endurance performance and in pulmonary function, with accompanying enhanced subjective symptoms, following exposure to low O3 levels commonly observed in numerous metropolitan environments during the summer months.

Adult↗
PubMed1986

Ergonomics and cumulative trauma disorders.

Chronic tendon and nerve disorders of the upper extremity, such as tendinitis and carpal tunnel syndrome, are a common problem among persons who routinely perform hand-intensive work. This article summarizes the most commonly reported occupational risk factors: repetitiveness, forcefulness, certain postures, mechanical stresses, exposure to vibration, and exposure to low temperatures. It describes how to look for these factors and how to control them through the design of work equipment and procedures.

Arm Injuries↗
PubMed1986

Laboratory and on-ice test comparisons of anaerobic power of ice hockey players.

The suitability of the Wingate Anaerobic Test (WAT40) as a laboratory measure of anaerobic capacity (AnCap) and power (AnPow) of ice hockey players was tested against the Reed Repeat Sprint Skate-RSS (1979) and the Sargeant Anaerobic Skate (SAS40). Twenty-four university and Junior A players (20.2 +/- 1.6 years), assigned by random draw, performed the three tests over a seven day period. Blood lactate taken from an unwarmed finger tip was used to assess work intensity. The AnCap (7.7 +/- 0.2 Watts X kg-1) and AnPow (10.1 +/- 0.2 Watts X kg-1) for WAT40 were significantly lower (p less than 0.05) than for RSS (AnCap 9.3 +/- 0.8 Watts X kg-1; AnPow 11.5 +/- 1.1 Watts X kg-1) and SAS40 (AnCap 9.7 +/- 0.8 Watts X kg-1; AnPow 11.9 +/- 1.8 Watts X kg-1). SAS40 was significantly higher (p less than 0.05) than RSS for both AnCap and AnPow. The RSS (r = 0.96; ME 4.5%) and SAS40 (r = 0.97; ME = 3.6%) showed excellent test-retest reliability and reproducibility for AnCap but were only fair on AnPow (RSS: r = 0.73; ME = 10.7%; SAS40: r = 0.65; ME = 18.4%). While the correlations among the tests (AnCap: SAS40 vs WAT40, r = 0.73; RSS vs WAT40, r = 0.69) were significant (p less than 0.05), the highest predictive capability estimate (r2) was only 53.3%. The correlations for blood lactates (WAT40: 10.8 +/- 1.5 mmol X l-1; SAS40: 10.7 +/- 1.9 mmol X l-1; RSS: 11.5 +/- 1.6 mmol X l-1) were not significant. Based upon the particular protocol used, the laboratory test WAT40 does not demonstrate a high relationship with on-ice measures of AnCap and AnPow in this group of ice hockey players.

Adolescent↗
PubMed1986

Biochemistry of muscle fatigue.

Fatigue--or decrease in force generation--is a reduction of simultaneously attached cross-bridges in the force generating state. Two processes are necessary for the force generation: Firstly Ca++ release from the sarcoplasmic reticulum to the sarcoplasm and the binding of Ca++ by the troponin molecule and secondly the turnover of myosin-actin cross-bridges. These processes require energy in at least three different ATPase reactions and can consequently be inhibited when ATP hydrolysis is decreased, i.e. when ATP content is to low or when the reaction products (ADP, Pi and H+) reach inhibiting levels or when muscle pH has decreased to values inhibiting actomyosin ATPase activity (22). Low pH will also decrease Ca++ release and Ca++ affinity by troponin (23). In isometric contraction the force is well preserved as long as ADP phosphorylation can be provided by both PCr degradation and anaerobic glycolysis. When the PCr store is exhausted the force starts to decline and if muscle activation is maintained the force will continue to decrease along with falling glycolytic rate. ADP phosphorylation rate decreases successively and ATP content falls with an at least transient increase in ADP. The ATP decrease, apart from the minor increase in ADP, is balanced by an equimolar increase in IMP. Lactate accumulation produces an increasing acidity with muscle pH values down to 6.25. Early changes in free ADP content cannot be excluded as reason for the initial decrease in force production followed by more pronounced inhibition of ATPase activity during continued contraction due to both substrate lack and product inhibition together with pH effect on the excitation--contraction mechanism. In dynamic exercise with supramaximum work intensity the relation between fatigue development and metabolism is similar. In prolonged dynamic exercise relying on oxidative metabolism without lactate formation the point of fatigue is reached when the glycogen store is exhausted. Again ADP phosphorylation rate is decreased when the energy substrate is changed from carbohydrate to fat with lower maximum rate of ATP resynthesis.

Adenosine Triphosphate↗
PubMed1985

[Ultrastructural changes in the red muscle fibers of the quadriceps muscle of the rat femur during increased motor activity].

Experiments on rats were made to study the effect of physical exercise running in a treadbahn on ultrastructure of skeletal muscle fibers. The biphasic mechanism of muscle contractile activity was shown. The processes of destruction occurring in red muscle fibers of the intensely working quadriceps femoris were manifested by enlargement of T system and sarcoplasmic reticulum elements, mitochondrial matrix swelling, cryst destruction, vacuolar degeneration of part of the mitochondria, and destruction of individual myofibrils. In addition to destructive changes, the muscle exhibited the recovery processes--physiological regeneration. Those processes included large accumulations of the mitochondria beneath the plasma membrane of muscle fibers, the presence of small mitochondria, division of the mitochondria, transformation of myosatellitocytes to myoblasts, the presence of centrioles in endotheliocytes, and so forth.

Animals↗
PubMed1978

Psychological states and aerobic fitness of male and female recruits before and after basic training.

Psychological states and aerobic fitness were measured using a battery of psychological tests and a bicycle ergometer work test. A group of approximately two hundred male and female subjects were tested at the beginning of a six week basic training cycle and another group of two hundred were tested at the completion of basic training. A difference in mood, anxiety, self confidence and physical fitness was evident in the groups of male recruits, but not in the female recruits after training. A significant difference existed between males and females in terms of physical work capacity. These differences in work capacity and psychological responses should be considered in the assignment and selection of personnel for high work intensity military occupations.

Adolescent↗
PubMed1984

Invasive exercise testing.

The normal hemodynamic response to dynamic supine exercise embodies the following features: progressive increase in heart rate relative to the work intensity; an increase in cardiac output of 600 ml or greater for every 100-ml increment in oxygen consumption; minimal increase in stroke volume; a progressive increase in oxygen extraction, attaining near-maximal levels during moderate exercise; and a minimal increase in left ventricular end-diastolic, pulmonary capillary wedge, pulmonary arterial, and right ventricular end-diastolic pressures. In heart disease, the major purpose of invasive exercise testing is to assess cardiac functional reserve capacity. An evaluation of the degree of encroachment on cardiac reserve by disease processes establishes hemodynamic correlates of clinical symptomatology and aids in selecting the proper therapeutic modality for each individual patient. In patients with ischemic heart disease, preliminary evidence indicates that invasive exercise testing in conjunction with angiographic findings may contribute additional substantial prognostic information.

Blood Pressure↗
PubMed1981

Extracorporeal fertilization and embryo transfer.

IVF may be used for diagnostic or therapeutic reasons. In patients with idiopathic infertility IVF may distinguish between defects in the spermatozoa or oocyte. At present IVF and ET offers patients with either tubal or idiopathic infertility only a small chance of becoming pregnant (4 to 13 per cent). General application of IVF and ET will be determined by future success rates and incidence of fetal malformation. Selection, preparation and management of patients requires a specialized team, meticulous attention to detail and intense work. The results at four steps in the procedure can be analysed: the rate of oocyte collection is 85 to 90 per cent, the rate of fertilization, 80 to 90 per cent, the rate of embryo development, 50 to 70 per cent, and the pregnancy rate per laparoscopy, 4 to 13 per cent. The factors determining success are not known. The collection of mature oocytes, the use of particular culture media and ease of embryo transfer are important. There are advantages in using clomiphene citrate HCG stimulation rather than the natural cycle. Pregnancy has occurred despite factors thought to be deleterious to IVF: general anaesthesia, carbon dioxide pneumoperitoneum, prolonged anaesthesia before oocyte collection and bleeding before or after ET. Ethical and legal aspects of IVF and ET require consideration by the community, legal profession and religious groups, and suitable guidelines need to be established for scientists and doctors.

Adult↗
PubMedDate not supplied

[Changes in the energetics of muscle contraction as a result of hyperoxia].

Using a highly sensitive thermometric method (1 X 10(-5) degrees C/mm), it was found that the heat production of a single isometric contraction of an isolated diaphragm of the rats exposed to 99% O2 at normal pressure for 3 and 6 hrs significantly differed from the norm: after 3 hr hyperoxygenation muscle heat production increased almost three-fold, and after 6 hr hyperoxygenation it decreased almost two-fold. The increase is regarded as a result of oxygen-potentiated increase of energy expenditures involved in a contraction and of a decrease of the performance of muscle contraction. The decrease is considered as a consequence of the primary in economical energy expenditures by an intensively working muscle represented by the diaphragm and of a reduced viability of the muscle preparation incubated in vitro.

Animals↗
PubMed1983

'Hyperactivity' in childhood.

The management of a 'hyperactive' child entails a thorough individual assessment, close communication with the school, intensive work with the family and the development of an individualised management plan which takes account of the unique circumstances of the child and his or her environment.

Attention Deficit Disorder with Hyperactivity↗
PubMed1981

[Effects of muscular exercise on non-glucoregulatory hormones (T3, rT3, T4, TSH, prolactin, FSH, LH) in type I diabetics (author's transl)].

In the present investigation the influence of muscular exercise on non-glucoregulatory hormones (T3, rT3, T4, TSH, prolactin) was analyzed in non-ketotic, juvenile-onset type diabetics (JD) in relation of their metabolic control. The plasma hormonal concentrations were measured in 8 well-controlled JD, 8 moderately controlled JD and in 8 healthy subjects, before, during and after a 30 min. bicycle ergometer test of moderate work intensity. The exercise-induced rise in T4, and rT3 was similar in both groups of diabetics and did not significantly differ with that obtained in controls. A significant increase of T3-concentrations occurred only in the controls. Hormone levels of TSH, FSH and LH did not change significantly during exercise in all three groups, whereas prolactin showed a considerable increase (N. S.) in the well-controlled JD-patient group with low blood glucose concentrations. These findings demonstrate that muscular exercise leads to a similar effect on the behavior of T4, rT3, TSH, LH, and FSH concentrations, but not on T3 (no increase) and prolactin in non-ketotic, conventionally treated JD compared with healthy individuals.

Adult↗