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At least 19 recordsLinked to original sources
PubMed1979

Time trends in the association of a rural or urban background with physician location.

The association of rural or urban background with choice of practice location was investigated in two time periods, 1950--1955 and 1963--1968, using the alumni of Marquette School of Medicine (now the Medical College of Wisconsin) in Milwaukee, Wisconsin. Background included size of communities of birth, high school, college, and internship. Small communities were screened to distinguish suburban from rural settings. It was found that in the 1950s the percentage of physicians from rural schools who chose to practice in rural areas was 2.2 times as great as this percentage for physicians from nonrural high schools (26 percent versus 12 percent). In the 1960s the ratio increased to 3.5, (35 percent versus 10 percent). This time trend was reversed for physicians more than 28 years old at the time of graduation from medical school. Place of birth and place of internship also were significantly associated with practice location; place of college showed a significant association with practice location only in the 1950s; and class rank was not associated with place of practice.

Age Factors↗
PubMed1979

Time trends in colo-rectal cancer mortality in relation to food and alcohol consumption: United States, United Kingdom, Australia and New Zealand.

Recent epidemiologically and experimental research has implicated dietary factors, including alcoholic drinks, in cancers of the colon and rectum. Analysis of time trends in cancer mortality since 1921, in the United States, England and Wales, Australia, and New Zealand, in relation to changes in per capita consumption of foodstuffs and alcohol reveals some support for the protective effect of fibre, but an inconsistent role for fat and meat in colon cancer. For rectal cancer, and to a lesser extent colon cancer, the most consistent correlate in comparisons across time, and between place, sex, and age-group, is beer consumption. Possible reasons for this correlation within this data set are discussed.

Adult↗
PubMed1979

Time trends in prognosis of patients with myocardial infarction: a population-based study.

A population-based study was conducted in metropolitan Baltimore, in which the prognosis of 504 patients hospitalized with acute myocardial infarction (MI) from July 1966 through June 1967 was compared with that of 803 patients hospitalized from January through December 1971. For patients admitted to coronary care units (CCUs), the in-hospital case-fatality rate (CFR) in 1971 (20%) was found to be significantly lower than that in 1966/67 (27.5%) (p less than .025), after simultaneous adjustment for 16 variables which may affect prognosis. No such significant difference was detected for patients not admitted to CCUs when the two time periods were compared. As a result of these time trends, CFRs were not significantly different between CCU and non-CCU patients in 1966/67, but in 1971 a significant advantage was shown for CCU patients (p less than .005). These results suggest that effectiveness of CCUs in prevention of in-hospital deaths increased between 1966/67 and 1971. For hospital survivors, regardless of admission to a CCU, no significant differences in long-term prognosis were found between patients discharged in 1971 and those discharged in 1966/67. This finding may reflect the lack of major therapeutic advances between the two study periods, aimed at reducing the progression of coronary atherosclerosis and/or the extent of the infarcted area.

Acute Disease↗
PubMed1979

First admissions for psychosis in Turku. A time trend study.

Patients over 15 years of age from Turku hospitalized for psychosis for the first time during the years 1949-50, 1959-60 or 1969-70 were investigated. The incidence of hospitalized psychoses (per 100,000 inhabitants) was 115, 136 and 160, respectively. The increase in incidence was greater in women than in men. The incidence remained approximately the same in patients aged 30 to 59, but increased in the younger and older groups. The incidence of functional psychoses increased; in schizophrenia, however, it declined, while in paranoid and effective psychoses it increased. In organic psychoses, the admission frequency of psychoses of old age rose in the 1950's, but declined in some measure in the 1960's. The incidence of psychosis increased for single persons. The ratio of the incidence between single and married persons rose in men, whereas in women it fell. This was particularly pronounced in schizophrenics. The incidence of psychosis was highest in unskilled laborers. The overrepresentation of schizophrenia and paranoid psychoses seemed to have become more pronounced in this occupational group.

Adolescent↗
PubMed1975

Time trends and periodic cycles in REM sleep eye movements.

Eye movements during REM sleep episodes were tabulated in 16 young adults. REM episodes were then broken down into four ranges according to length in min: (1) 11.0-21.3; (2) 21.7-29.7; (3) 30.0-42.3; (4) 42.7 or longer. These data were then analyzed for linear and quadratic trends. Eight episodes had a significant linear trend, 10 had a significant quadratic trend, 7 had both linear and quadratic trends, while 12 had no trend. The residuals from the best-fitting polynomial curve were then subject to a spectral analysis. In addition, 2 long periods of pre-sleep wakefulness (approximately 2 h each) were also analyzed. In general, the spectral analysis revealed the dominant presence of a slow cycle (period of 10 min to about 30 min) the exact period of which varied according to the length of the REM episode. A binomial probability test indicated that the presence of slow cycles was significant in REM episodes except for those in the 21-30 min range. For the episodes of wakefulness, a dominant slow cycle was found in both cases. The results give the impression of similarity in the periodic organization of eye movements during REM sleep and waking. The data also indicated that an ultradian (70-150 min) cycle was present in eye movements during sleep and waking. Further, the finding of a decrease in eye movements before sleep onset, coupled with previous reports of an increase in eye movement after sleep onset, indicate the presence of a circadian cycle.

Adolescent↗
PubMed1979

Interrelationships of circulating maternal steroid concentrations in third trimester pregnancies. II. C18 and C19 steroids: estradiol, estriol, dehydroepiandrosterone, dehydroepiandrosterone sulfate, delta 5-androstenediol, delta 4-androstenedione, testosterone, and dihydrotestosterone.

This report describes aggregate time trend effects of advancing gestational age on circulating maternal concentrations of 17beta-estradiol (E2), estriol (E3), dehydroepiandrosterone (D), dehydroepiandrosterone sulfate (D-S), delta 5-androstenediol (delta 5 diol), delta 4-androstenedione (delta 4 A), testosterone (T), and dihydrotestosterone (DHT) in a sequential series of 155 blood samples obtained from 19 normal pregnant women ranging from 26-40 weeks gestational age. Only E2, E3, and D-S show aggregate time trend effects. Log (E2) plots as a linear positive sloping curve from 26-40 weeks. Log (E3) plots as a positive sloping curve that is significantly steeper than log (E2) (P less than 0.05). Log (D-S) plots into a negative sloping curve which mirrors the pattern for log (E2) but cannot be statistically associated with log (E2) except for the opposite sign of their slopes, which are both significantly different from a zero slope (P less than 0.05). delta 4 A, T, DHT, delta 5 diol, and D show no aggregate time trends; however wide, comoving undulations for delta 4 A, T, DHT, and delta 5 diol between 26-28 and 38-40 weeks are confirmed in time by comparison of log mean plots and in magnitude by regressing the C19 steroids on one another. D shows virtually no association with the other C19 steroids. All C19 steroids, except for T, circulate at nonpregnant concentrations, implying that there is little placental secretion of these steroids into the maternal circulation.

Androgens↗
PubMed1976

Effects of citrus pulp in high urea rations for steers.

Effects of pelleted and conventional citrus pulp as a replacement for corn, with soybean meal added to keep protein comparable, were tested in rations with 5% urea and 33.33% sugarcane bagasse for fistulated steers. Thus, all rations were low in readily fermented carbohydrates other than those of corn or citrus pulp. Evaluation criteria were concentrations of urea in blood and of pH, ammonia, and volatile fatty acids of rumen fluid. Citrus pulp for diets 1, 2, 3, and 4 was 0, 19, 38, or 55%. Rumen fluid and blood were sampled 1 h before and 2, 4, 7, and 12 h after feed was placed directly into the rumen. No differences between pelleted and conventional pulp or among time trends were significant except that for both forms rumen ammonia was lower with the two highest percents of citrus pulp. Addition of citrus pulp at 0, 19, 38, or 55% of the ration reduced rumen pH (6.85, 6.65, 6.61, 6.51). Blood urea and rumen ammonia decreased in steers fed 19, 38, or 55% pulp; thus, the acetic to propionic ratio was higher. Butyric acid changed only in the time trend. Total volatile fatty acid concentrations were higher at 19, 38, and 55% than at 0% pulp. They were higher at 38 and 55 than at 19%.

Ammonia↗
PubMed1976

The temporal and periodic organization of REM eye movements in mental retardation.

Time trends and periodic cycles in REM sleep eye movements were examined in 6 functional and 6 mongoloid adolescent retardates. Both groups of subjects showed approximately equal percentages of linear trends, quadratic trends, linear and quadratic trends, and absence of trend. The eye movement time-series were subject to an orthogonal spectral analysis. In both groups of subjects, peak spectral estimates generally occurred at 10.6- or 21.3-min periods. Following this, the eye movements of the longest REM periods (and one long period of pre-sleep wakefulness) were subject to a least-squares spectral analysis. This analysis yielded estimates ranging from 22 to 44 min. Eye movements lacked the ultradian organization previously reported for eye movements of normal subjects. These results imply that the ultradian organization of REM sleep and the ultradian organization of eye movements may be independent.

Adolescent↗
PubMed1977

Stranger responses: effects of familiarity, stranger's approach, and sex of infant.

Most investigators examining contextual influences on infant responses to a stranger have limited their study to the initial responses of the infant. Few have considered infant reactions beyond the first minutes of the encounter or the enduring effects of contextual variables once mothers have left. The present study examines the effects of stranger's style of approach, familiarity with the stranger, and infant sex on infant response before and after maternal separation. Familiarity was operationalized in 2 ways: the length of time mothers stayed before leaving infants with the stranger and meeting the stranger a second time. Findings suggest that all these factors influence infant behavior. Ifants looked and smiled at the stranger significantly more when approached slowly. Contrary to expectations, infants (particularly girls) who met the familiar stranger after 1 week protested significantly more when left with her at that time. Trends indicate the length of time mothers stayed was least influential since most infants became extremely distressed once mothers departed.

Child Behavior↗
PubMed1978

Increases in laryngeal cancer in Britain and Australia in relation to alcohol and tobacco consumption trends.

The incidence of laryngeal and oesophageal cancers has recently risen in Britain and Australia, particularly in younger people, after many decades of steady decline. In view of accruing evidence that head-and-neck cancers are causally related to alcohol and tobacco consumption, particularly in combination, it seems that the upsurge in consumption of alcohol and cigarettes after the 1939-45 war is now reflected in the increases in these two cancers, particularly in young women. The time-trends in sex-specific mortality from cancers of the larynx and oesophagus throughout this century, in both Britain and Australia, show strong correlations with alcohol consumption. By reference to inter-country differences in consumption trends, to differences in consumption of alcohol and cigarettes, to sex differences in cigarette consumption, to trends in types of alcoholic drink consumed, and to the mortality experienced of successive generations, the evidence that alcohol is causally related to laryngeal cancer is strengthened.

Adult↗
PubMed1977

Role of the cancer registry.

The cancer registry can be defined as a facility for the collection, storage, analysis, and interpretation of data on persons with cancer. The possible range of registry activities was discussed in relation to the population-based cancer registry. These activities included service to the medical profession and hence the cancer patient, the provision of information for planning control measures, the evaluation of treatment and of screening programs, the conduct of epidemiologic studies, either directly or indirectly, and the education of the public and the medical profession. The resources of the cancer registry can be used in follow-up for industrial and other cohorts exposed to a variety of agents. Registries must be prepared to meet the problem of confidentiality that might arise when information in the registry is linked with other data sets. The value of a cancer registry increases when it becomes possible to examine and assess time trends. Unfortunately, many cancer registries were not adequately funded or staffed to exploit usefully the data already collected at considerable expenses. The three types of staff required to ensure full utilization were discussed.

Economics, Medical↗
PubMed1979

Convenience and the occurrence of births: induction of labor in the United States and Canada.

This paper, using data for the United States and Canada on number of births by day of the week, presents indirect evidence for the widespread incidence of the practice of elective induction. For both the United States and Canada, it is found that substantially fewer births occur on Saturdays, Sundays, and holidays than on weekdays. Controlling for such factors as prenatal care, race, education, legitimacy, birth weight, and time trend strongly suggests that the induction of labor is responsible for the patterns found. The paper concludes by discussing the framework within which the practice of elective induction of labor should be evaluated and justified.

Appointments and Schedules↗