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PubMed1996

Hemodynamic effects of aerobic vs resistance exercise.

Previous studies suggest that aerobic exercise lowers blood pressure (BP), while isometric exercise increases BP, at least transiently. The purpose of this study was to examine the hemodynamic effect of a 6-week training period of aerobic exercise or weight training. Twenty deconditioned healthy males ages 18-36, self-selected a training regimen. The aerobic group exercised 30 min/day, 4 times each week to achieve 60-80% maximal heart rate. The resistance group lifted weights at 65-80% maximal voluntary contraction; 3-4 sets of 8-12 repetitions; 3 day/week using large muscle groups. Hemodynamic measurements of heart rate, BP, venous capacitance, forearm blood flow, and vascular resistance were made at baseline and week 6 by plethysmography and analyzed by 2-way ANOVA. The groups showed no differences in baseline characteristics. A training effect was confirmed by a decrease in resting heart rate in the aerobic group (71.5 +/- 4.4 to 64.5 +/- 3.7, beats per minute, P = 0.004), and an increase in total work capacity in the weight lifting group (6231 vs 7508, P = 0.01). Forearm blood flow increased similarly in both groups, averaging 17% (3.5 +/- 0.2 vs 4.2 +/- 0.2 ml 100 g/min, P = 0.03), while forearm vascular resistance fell 19% (28.8 +/- 1.7 vs 24.3 +/- 1.7 mm Hg/ml/min 100 g, P = 0.08). The main differences between the groups after training was found in their response to isometric stress (1/3 maximal handgrip). The weight-lifting group had a greater increase of forearm blood flow and venous capacitance, less increase in systolic BP (SBP) and a greater fall of forearm vascular resistance, (P < 0.05) while the aerobic group had less increase in SBP and heart rate (P < 0.04) but no significant change of forearm hemodynamics. We conclude that both aerobic and repetitive weight programs have short term favorable effects on resting forearm BP and resistance. The exercise programs differ in altering the individual's physiologic response to subsequent isometric stress. However, exercise training of longer duration or greater intensity or frequency could alter these results.

Adult↗

PubMed1996

Use of the Pap test by a population group in Buenos Aires.

The study reported here sought to assess Pap test coverage of a group of asymptomatic Argentine women from the poor urban district of La Matanza in the Buenos Aires metropolitan area Initially, all 2495 women who voluntarily enrolled in a program for early detection of breast cancer between January 1991 and June 1993 were included. After removing those who did not meet various study criteria, there remained 779 study subjects with no gynecologic or mammary symptomatology. Two subgroups of these 779 were established-women who had received a Pap test at any time and those who had received such a test within the previous three years. Using these subgroups, the influence of certain sociodemographic and other variables upon the likelihood of Pap testing was assessed. The results indicated significant associations between past Pap testing and age, formal education, parity, and a family history of cancer Likewise, significant associations were found between Pap testing within the preceding three years and age, formal education, and parity. The study findings affirm the idea that it would be advisable to seek Pap testing for all study population women once every three years instead of every year. Since the study population was not necessarily representative of Buenos Aires population, however, and the findings could have been affected by self-selection and other biases, additional studies are needed to determine actual Pap test coverage among women of the metropolitan area.

Adult↗

PubMed1997

Step treadmill exercise training and blood pressure reduction in women with mild hypertension.

Stepping as an exercise modality has gained increasing popularity. The step treadmill is an exercise machine which simulates actual stair-climbing. The purpose of this study was to determine the effectiveness of a 16-week supervised aerobic step treadmill exercise training protocol in reducing resting blood pressure in women with unmedicated mild hypertension. During the training protocol, subjects exercised during a self-selected appointment three times a week on the step treadmill, increasing from 20 minutes up to 60 minutes per session, at a target heart rate corresponding to 70-80% heart rate reserve for 16 weeks. Utilizing paired t-test analysis, mean resting systolic blood pressure decreased from 142.2 +/- 9.1 to 132.7 +/- 8.2 mm Hg (p < .01) and mean resting diastolic blood pressure decreased from 93 +/- 4.9 to 87.4 +/- 5.4 mm Hg (p < .01) during the 16-week protocol. Mean maximal oxygen uptake was significantly increased, whereas mean body weight did not change significantly over the 16-week period. Large scale trials are needed to further delineate the effectiveness of stepping as a health care intervention in adults with unmedicated mild hypertension, especially in women.

Adult↗

PubMed1997

The effects of the ALSO course as an educational intervention for residents. Advanced Life Support in Obstetrics.

BACKGROUND AND OBJECTIVES: Previous descriptions of the Advanced Life Support in Obstetrics (ALSO) course have indicated increases in physician comfort in managing obstetric emergencies and in their intentions to continue offering maternity care after taking the course. No previous studies have been done about the educational outcomes of the ALSO course on family practice residents. This study compared residents' pre- and post-ALSO course confidence to manage obstetrical emergencies and their intention to provide maternity care when they enter practice. METHODS: A self-selected group of 55 family practice residents completed questionnaires before and after ALSO training. The questionnaire was designed to measure confidence, using Bandura's model of self efficacy, and future intention, using Ajzen's Theory of Planned Behavior. RESULTS: Residents' confidence in their abilities to manage obstetrical emergencies increased significantly after the ALSO course. Residents' intent to provide maternity care when the residents enter practice did not change. CONCLUSIONS: The ALSO course is a valuable teaching intervention that can improve family practice residents' perceived self-confidence in managing obstetric emergencies. The study had sufficient power to detect a moderate effect size of the ALSO course on resident intention to provide maternity care but did not do so.

Analysis of Variance↗

PubMed1997

Proteins and bone health.

Hip fracture consecutive to osteoporosis represents a major health problem in terms of both morbidity and financial burden for the community. Deficiency in nutritional elements appear to play a major role in the pathogenesis of osteoporosis and of fractures in elderly. Correction of an inadequate supply in both calcium and vitamin D can reduce bone loss and fracture incidence in elderly subjects. In addition, low protein intake could be particularly detrimental for the conservation of bone integrity with aging. Thus, in hospitalized elderly patients reduced protein intake is associated with lower femoral neck bone mineral density (BMD) and poor physical performance. Furthermore, state of malnutrition or undernutrition is often observed in elderly patients with hip fracture. In these patients, in who we detected very low femoral neck (BMD) at the level of the proximal femur, the self-selected intake of protein and energy was insufficient during their hospitalization. Interestingly, the clinical outcome after hip fracture was significantly improved by daily oral nutritional supplement normalizing the protein intake, documented as a reduction in both complication rate and median duration of hospital stay. Further studies showed that normalization of the protein intake, independently of that of energy, calcium and vitamin D, was responsible for this more favorable outcome, and could prevent further bone loss, at least at the level of weight-bearing cortical bone. In undernourished elderly subjects an increase in the protein intake, from low to normal, could be beneficial for bone integrity. This could act through an increase in the growth factor IGF-1 which has been found to decrease with aging.

Aged↗

PubMed1997

The experience of dying with dementia: a retrospective study.

OBJECTIVE: To describe the last year of life of people with dementia, their symptoms, care needs, use of and satisfaction with health services and the bereavement state of the respondent. METHODS: The study is drawn from the Regional Study of Care for the Dying, a retrospective sample survey of the carers, family members or others who knew about the last year of life of a random sample of people age 15 and over dying in the last quarter of 1990. The samples were drawn in 20 English health districts which, although self-selected, were nationally representative. There was a total of 3696 patients (response rate of 69%) dying from all causes. Within this sample, 170 dementia patients were identified and compared with 1513 cancer patients. RESULTS: The symptoms most commonly reported in the last year were mental confusion (83%), urinary incontinence (72%), pain (64%), low mood (61%), constipation (59%) and loss of appetite (57%). Dementia patients saw their GP less often than cancer patients and their respondents rated GP assistance less highly. Dementia patients needed more help at home compared with cancer patients, and received more social services; 78% of respondents for dementia patients and 64% for cancer said they had come to terms with the patient's death. CONCLUSION: Patients dying from dementia have symptoms and health care needs comparable with cancer patients. Greater attention should be given to these needs.

Aged↗

PubMed1997

Dimensions of marital relationships as perceived by Turkish husbands and wives.

In this study, the basic underlying dimensions and interrelationships of Turkish urban marriages were explored. Both husbands and wives from 456 marriages of different types, lengths, and socioeconomic status (SES) groups completed the extensive Turkish Marriage Questionnaire (Russell, Wells, & Imamoğlu, 1989). First-order factor analysis yielded 9 factors that were then reduced to 4 second-order factors: Extent of Socioeconomic Development, Marital Satisfaction, Harmonious Relations With the Extended Family, and Desire for Sexual Possessiveness. The frequency of self-selected marriages increased with higher SES and decreased with length of marriage, implying a trend toward modernism. Within this context, husbands' marital satisfaction and wives' desire for sexual possessiveness, extent of socioeconomic development, and relations with the extended family were significant predictors of wives' marital satisfaction; husbands' marital satisfaction was predicted by wives' satisfaction and husbands' relations with the extended family.

Adult↗

PubMedDate not supplied

[Seroprevalence of various viruses and sociodemographic characteristics of women seeking HIV screening].

OBJECTIVES: To study the seroprevalence of syphilis, herpes simplex-2, hepatitis B and HIV, and main sociodemographic characteristics and sexual behavior in women seeking testing for human immunodeficiency virus (HIV) in Mexico City. METHODOLOGY: A self-applied questionnaire was used in 454 women; and a blood sample was taken for the detection of markers for syphilis, herpes simplex virus-2 (HSV-2)), antibodies against core and surface antigens for hepatitis B virus (HBV), and ELISA and Western blot for HIV. RESULTS: Seroprevalences for antibodies against T. pallidum, HSV-2, HBV and HIV were 4.6%, 29.3%, 3.5% and 4.0%, respectively. Forty-six percent of the women were 20 to 29 years old; 70% reported complete junior high school or higher education level; 75% were sexually active; 56% reported at least one stable male sexual partner, 17% reported at least one occasional male sexual partner in the last three months, and 60% had had at least one sexual relation in the last three months; of these, only 18% (n = 82) reported the use of a condom as a preventive measure. Almost 30% of the HIV positive women had a history of blood transfusion, while less than 10% of the HIV negative women had received a transfusion. In addition, 10.6% said that one of their sexual partners was infected with HIV or had AIDS. CONCLUSIONS: Risks of HIV/STD transmission for this group of self-selected women were linked to blood transfusion, low education and, most important, the risk from male sexual partners who were HIV seropositive. It is expected that these results will contribute to the improvement and development of strategies for the control and prevention of STD among this population group, as well as the general population in Mexico.

AIDS Serodiagnosis↗

PubMed1977

Outcomes of elective home births: a series of 1,146 cases.

Medical records of 1,146 elective home births from five home delivery services in northern California were reviewed. Three of the services consisted of family physicians and nurses, whereas two consisted of lay midwives without immediate physician supervision. Rates of medical complications in both groups were low. Perinatal morbidity and mortality were lower than California averages. Fifteen premature infants (1.3%) were delivered successfully. Apgar scores were high. Four infants (0.3%) were neurologically abnormal at follow-up. The perinatal mortality rate was 9.5 per 1,000 total births. There were no maternal deaths. These figures demonstrate that in a self-selected, medically screened, low-risk population, home delivery with medical facility back-up can be a reasonable alternative to hospital delivery. Possible reasons for the good results obtained are cited.

Adult↗

PubMed1997

Hassles, appraisals, coping and distress: a closer look at the stress process.

In this exploratory study, important components of the stress process were under close scrutiny. Subjects self-administered a computer programmed interview, which started with a self-selected daily hassle and went on to examine the person's appraisals of the incident, actions taken towards it and its impact on the person. Its Personal evaluations of coping efficacy and personal decisions of coping consistency were also probed. Results suggested that daily hassles were recurrent and minor in nature; and people tended to make mixed and combined appraisals of these hassles. Perceived coping efficacy affected perceived stress impact and future coping consistency. It seemed that there was a self-monitoring mechanism in the coping process, and people's coping efforts tended to be rather economical.

Adaptation, Psychological↗

PubMed1997

Breast carcinoma stage in relation to time interval since last mammography: a registry-based study. The Romagna Cancer Registry and Collaborators.

BACKGROUND: In the Romagna Region of Italy, mammography screening for breast carcinoma (BC) was implemented as a routine practice in the regular healthcare system. The Romagna Cancer Registry evaluated the effects of self-selection for mammography on the stage of BC at the time of presentation. METHODS: Of the 851 invasive BC cases registered in 1989-1991, tumor size (T) was documented for 790 (93%) and lymph node status (N) for 681 (80%). Mammography experience was determined by cross-checks with the radiology files in the area. The Mantel-Haenszel chi-square test stratified by age was used to evaluate the difference in the proportion of advanced BC between subsets of patients diagnosed at increasing time intervals since their most recent mammography and those with no previous examination. RESULTS: The incidence of T2+/N1+ (T2 or worse and/or lymph node positive) BC was 71% among patients without previous mammography. No advantage was observed for patients diagnosed within 6-12 months of their last mammography (69%). A marked advantage was associated with intervals varying between 12-23 months (45%; P < 0.001) and between 24-35 months (43%; P < 0.001). For longer intervals, the proportion of T2+/N1+ disease stabilized at 56%. For patients with any interval > 5 years (range, 5-22 years; median, 11 years) the relative stage advantage was significant (P = 0.013). CONCLUSIONS: The stage pattern of patients diagnosed with BC 5-22 years after their last mammography suggests that even if health-aware women who volunteered for screening stop undergoing regular mammography, they present for a relatively prompt diagnosis in the event they develop BC.

Adult↗

PubMed1997

New England eye care survey.

BACKGROUND: Descriptive statistics on patient or consumer use of eye care are important for health care policy and professional development. Most survey research has been through doctors or doctors' offices. Some consumer surveys have been completed by direct mail, but information from direct mail surveys suffers from respondent self selection. This study joins a growing number of surveys designs that use random-digit telephone survey methods, which have less self-selection bias. METHODS: This study describes patient use and perceptions of eye care services in three New England areas using random-digit telephone survey. Nine hundred eighteen calls were attempted. A standardized interview and survey questionnaire was used for each phone contact. RESULTS: Of 163 respondents (18% response rate), it was found that most patients were satisfied with the care, time, discussion, and fees provided by their eye care practitioner. Most (78%) planned on returning to the same practitioner in the future. Sixty percent of participants saw an optometrist, 29% saw an ophthalmologist, and 11% were unsure. In a subsample, differences in perception between optometric and ophthalmologic care was investigated, and no statistically significant differences (p < 0.05) were found. CONCLUSIONS: The study findings are similar to others in terms of market share between optometric and ophthalmologic settings for primary eye care. Several new findings were measured and discussed, and the data may be helpful for policy decisions.

Adolescent↗

PubMed1997

Distant intentionality and healing: assessing the evidence.

Since the 1950s, researchers have attempted to understand reports of distant or "psychic" healing, developing experimental protocols that test the distant healing hypothesis by measuring biological changes in a target system while ruling out suggestion or self-regulation as counterexplanations. This article provides a brief overview of these "healing analog" experiments. It also provides a summary and meta-analysis of 30 formal experiments in which self-reported healers, "psychics," and other self-selected volunteers attempted to influence autonomic nervous system activity in a distant person. Results across the experiments showed a significant and characteristic variation during distant intentionality periods, compared with randomly interspersed control periods. Possible alternative explanations for the reported effects are considered. Finally the implications of distant intentionality are discussed for an understanding of the possible mechanisms of distant healing, the nature of the mind-body relationship, and the role of consciousness in the physical world.

Complementary Therapies↗

PubMed1997

Oxygen consumption and energy expenditure of level versus downhill running.

OBJECTIVE: The purpose of this study was to assess and compare submaximal oxygen consumption (VO2) and energy expenditure (kJ) while running at 0, -1.8, -3.6, and -5.4% grades for three individually selected running speeds (9.4 + 0.79, 10.3 + 0.74, 11.3 + 0.73 km.h-1). EXPERIMENTAL DESIGN: Subjects completed the four grade conditions in random order via a modified Latin squares design at three self-selected submaximal running speeds for each condition. PARTICIPANTS: Thirteen (5 females and 8 males) recreational (< 35 km.wk-1) runners (age: 27.7 +/- 4.3 yrs) volunteered for the study. MEASURES: Two-way repeated measures ANOVA (Grade x Speed) was used to analyze steady-state VO2 and kJ expenditure. Stepwise linear multiple regression was used to develop an equation for predicting VO2 for running at recreational speeds on moderately negative grades. RESULTS: VO2 and kJ mean values were significantly different between all speed and % grade comparisons. Compared to level grade, the average reductions in VO2 and kJ expenditure ranged from approximately 9% at a grade of -1.8% to 22% at a grade of -5.4%. The relationship between VO2 and % grade for each running speed was linear. CONCLUSIONS: For a given speed, running at a modest negative grade can significantly decrease VO2 and kJ expenditure compared to level running. The following regression equation can be used to estimate VO2 (ml.kg-1.min-1) for running at recreational speeds on slight downhills: VO2 = 6.8192 + 0.1313 (speed in m.min-1) + 1.2367 (% grade).

Adult↗

PubMed1997

Symptoms and differential diagnosis of patients fearing mercury toxicity from amalgam fillings.

Clinical signs, somatic symptoms reported by patients, and mercury excretion in urine were studied for 348 patients selected by odontologists or internists as amalgam-free referents, or as subjects with unexplained clinical findings or who were self-selected due to their fear of mercury intoxication from their amalgam fillings. Sixty patients were excluded because other explanations could be given for their complaints. The age distribution was bimodal, with peaks between 30 and 35 years and between 45 and 50 years. Mercury was determined in a morning urine sample and 30 minutes after the injection of 300 mg of 2,3 dimercapto-1-propane sulfonic acid (DMPS), a mercury-chelating agent. The patients were followed for 1-3 years. Among the patients there were 26 who had had their amalgam fillings removed and who, at the time of the follow-up, were subjectively cured. When the patients were classified according to the excretion of mercury after the DMPS challenge, those who belonged to the upper quartile had an odds ratio of 7.2 (95% confidence interval 3.1-15.2) for becoming cured after amalgam removal. The symptoms of the cured patients had been predominantly mental. No consistent clinical picture could, however, be found among the other patients, as various types of mental and physical distress were reported.

Adult↗

PubMed1998

Hormonal-induced changes on the lipid composition and DPH fluorescence anisotropy of erythrocyte ghost from pre- and postmenopausal women.

Fluorescence anisotropy determinations were performed on hypotonically lysed red blood cells from 12 healthy, free living, premenopausal and 10 postmenopausal women fed a self-selected diet. Fatty acid composition of phospholipids and cholesterol esters, lipid/lipid and lipid/protein ratios were also determined in erythrocyte ghosts along the menstrual cycle or during hormonal replacement therapy. The postmenopausal women were treated with transdermal 17-beta estradiol (approx, delivery rate of 50 micrograms/day) for a 5-week period and with a combination of percutaneous administration of estradiol and orally administered medroxyprogesterone acetate (5 mg/day) for 5 weeks more. Premenopausal women were studied in the mid-follicular and mid-luteal phases of their menstrual cycles. Membrane fluidity in cells from the luteal phase was greater than that observed in the follicular phase. After estradiol treatment, postmenopausal women exhibited a significant raise in the fluorescence anisotropy. The association with progesterone prevented the estrogen-induced increase of the anisotropy values. Estrogen administration also produced an increment in the relative content of cholesterol and membrane proteins that was reverted by progesterone addition. Changes induced by estradiol treatment in the fatty acid pattern of phospholipids and cholesterol esters were characterized by an increment in the monoenoic/saturated fatty acid ratio and linoleic relative content, with a concomitant decrease in the proportion of arachidonic and docosatetraenoic acids. These results suggest that the modification of the desaturase activities may be involved in a mechanism by which these hormonal-induced changes take place. The present study demonstrated that human erythrocyte fluidity is under hormonal control subjected through changes in the proportion and quality of the membrane lipids.

Adult↗

PubMed1997

Prevalence of asthma and rhinitis in Perugia, Italy.

This cross-sectional study evaluated the prevalence of, and risk factors for, asthma and rhinitis in a randomized sample of males and females, aged 0-69 yrs, in Perugia, Italy. To determine the prevalence of asthma and rhinitis, 824 subjects were interviewed by trained physicians using a modified American Thoracic Society and National Heart and Lung Institute-Division of Lung Disease questionnaire proposed in 1978 (ATS-DLD-78). Skin-prick tests were carried out in 667 subjects > or = 3 yrs of age. Age, sex, atopy, smoking, and household pets were considered potential risk factors for the development of asthma and rhinitis. Cumulative prevalences of: asthma was 8.1%; current asthma 5.0%; and rhinitis 15.2%. Positive skin tests were observed in 21.3% of subjects: in 63.4% of the cases of current asthma and in 68.7% of rhinitis cases. The prevalence of asthma and rhinitis was similar in both sexes. Prevalence of current asthma was almost three times higher in childhood than after the age of 10 yrs. Positive skin tests for pollens and house dust mite were the most prevalent risk factors for asthma. Current smoking was inversely associated with prevalence of current asthma possibly because of a self-selecting effect. Household pets were found not to be major risk factors for asthma or rhinitis. In conclusion, prevalence of asthma and rhinitis is a common health problem in the Perugia area, and atopy, particularly pollen sensitivity, is the most important risk factor for the development of asthma and rhinitis.

Adult↗

PubMed1997

Effect of provider characteristics on choice of contraceptive provider: a two-equation full-information maximum-likelihood estimation.

We use surveys of households and health-care facilities conducted in the same area at the same time to determine which characteristics of providers attract users of contraceptives. By using the full-information maximum-likelihood technique to jointly estimate choice of contraceptive method and choice of provider, we avoid self-selection bias. Results support the need for modeling quality and for jointly estimating the choice of contraceptive method and the choice of provider to avoid biased estimates of coefficients. The results suggest that for the Cebu, Philippines region, small local clinics that focus on family planning tend to be most favored by clients.

Adolescent↗