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PubMed1990

Fertility adaptation of Turkish and Moroccan women in the Netherlands.

"After a short overview of fertility trends among Turkish and Moroccan immigrants in the Netherlands, based upon population and vital registration data, determinants of these trends are analysed using survey data on cumulative fertility as well as on desired fertility." The author concludes that although "a long time series of data is not yet available due to the fairly recent history of the migration of Turkish and Moroccan women to the Netherlands, it appears that their fertility level is declining. Migrant fertility levels are lower than in the countries of origin.... Factors in the decline of overall immigrant fertility are variables related to the country of destination: work and education, insofar as this education was received in the Netherlands." (SUMMARY IN FRE AND SPA)

Africa↗
PubMed1988

A comprehensive analysis of myocardial infarction due to left circumflex artery occlusion: comparison with infarction due to right coronary artery and left anterior descending artery occlusion.

Forty consecutive patients with creatine kinase-MB confirmed myocardial infarction due to circumflex artery occlusion (Group 1) were prospectively evaluated and compared with 107 patients with infarction due to right coronary artery occlusion (Group 2) and 94 with left anterior descending artery occlusion (Group 3). All 241 patients underwent exercise thallium-201 scintigraphy, radionuclide ventriculography, 24 h Holter electrocardiographic (ECG) monitoring and coronary arteriography before hospital discharge and were followed up for 39 +/- 18 months. There were no significant differences among the three infarct groups in age, gender, number of risk factors, prevalence and type of prior infarction, Norris index, Killip class and frequency of in-hospital complications. Acute ST segment elevation was present in only 48% of patients in Group 1 versus 71 and 72% in Groups 2 and 3, respectively (p = 0.012), and 38% of patients with a circumflex artery-related infarct had no significant ST changes (that is, elevation or depression) on admission (versus 21 and 20% for patients in Groups 2 and 3, respectively) (p = 0.001). Abnormal R waves in lead V1 were more common in Group 1 than in Group 2 (p less than 0.003) as was ST elevation in leads I, aVL and V4 to V6 (p less than or equal to 0.048). These differences in ECG findings between Group 1 and 2 patients correlated with a significantly higher prevalence of posterior and lateral wall asynergy in the group with a circumflex artery-related infarct. Infarct size based on peak creatine kinase levels and multiple radionuclide variables was intermediate in Group 1 compared with that in Group 2 (smallest) and Group 3 (largest). During long-term follow-up, the probability of recurrent cardiac events was similar in the three infarct groups. When patients with a circumflex artery-related infarct were stratified according to the presence or absence of abnormal R waves in lead V1 or V2, the abnormal R wave group had more admission ST elevation (p = 0.025), a larger infarct (p less than 0.05) and more extensive coronary artery disease (p = 0.027). In fact, all patients with a circumflex artery-related infarct and an abnormal R wave in lead V1 had multivessel disease. An abnormal R wave in lead V1 had a 96% specificity for circumflex versus right coronary artery-related infarction but a sensitivity of only 21%. Discriminate function analysis of all admission historical and ECG variables identified inferior and lateral ST elevation as independent predictors of circumflex artery-related infarction...

Angiography↗
PubMed1994

Immunization coverage and infant mortality rate in developing countries.

We examined whether immunization coverage (IMC) is one of the predictors of infant mortality rate (IMR), as a single indicator representing the availability of primary health care (PHC) services in developing countries. Multiple regression analysis showed that partial correlation coefficients for IMR with immunization coverage (-0.224), logarithm of per capita GNP (-0.294), total fertility rate (0.269), and adult literacy rate (-0.325) were all statistically significant (p < 0.001) in 97 developing countries which make up more than 97% of the population in all the developing countries of the world. Multiple correlation coefficients of IMR with these four variables in 97 countries was 0.921. Thus, more than 80% of variation of IMR in developing countries were explained by the variation of the four variables. The study also showed that IMC was well correlated (simple correlation) with the four indicators of the availability of primary health care services; access to local care (0.730), care of pregnant women (0.603), delivery care (0.666), and infant care (0.553), all of which were statistically significant (p < 0.001) in the 48 developing countries which make up 42% of the population of all developing countries. Multiple correlation coefficients of these four variables was 0.787. About 60% of the variation of IMC will be explained by the variation of the four variables. Thus we conclude that immunization coverage is one of the main predictors of the infant mortality rate. It represents one of the health intervention components which can be used as a proxy indicator of the availability of PHC service in developing countries.

Adult↗
PubMed1984

Glial fibrillary acidic protein (GFAP) immunoreactivity in peripheral nerve sheath tumors.

A spectrum of 24 benign and malignant nerve sheath tumors and 10 non-neural spindle-cell tumors were studied by light microscopy for the presence of glial fibrillary acidic protein (GFAP) immunoreactivity by the peroxidase-antiperoxidase (PAP) technique. In 8 cases, these results were compared to their electron microscopic appearances. Seventy percent (7 of 10) of benign schwannomas and 50% (4 of 8) of benign neurofibromas demonstrated focal to diffuse GFAP immunoreactivity. None of the malignant nerve sheath tumors nor any of the non-neural spindle-cell neoplasms contained demonstrable GFAP immunoreactivity. Similarly, no GFAP immunoreactivity could be detected in Schwann cells in normal peripheral nerves. The solitary benign schwannoma available for electron microscopic study demonstrated diffuse and abundant cytoplasmic intermediate filaments, and this tumor displayed diffuse and intense GFAP immunoreactivity. Two benign neurofibromas showed a more variable content of intermediate filaments ultrastructurally, and their GFAP immunoreactivity was variable. All five malignant nerve sheath tumors studied by electron microscopy displayed a variable complement of intermediate filaments; however, none of these tumors possessed GFAP immunoreactivity, suggesting that these intermediate filaments are either members of a different class of intermediate filaments or may perhaps represent "altered" GFAP not recognized by these antisera.

Cytoskeleton↗
PubMed1995

Adolescent contraceptive use and its determinants in Bangladesh: evidence from Bangladesh Fertility Survey 1989.

This study is concerned with contraceptive use among the currently married adolescents in Bangladesh utilizing the 1989 Bangladesh Fertility Survey (BFS) data. The study analyzes the factors affecting the current use of contraception among the adolescents through bivariate and multivariate logistic regression analysis. The results indicate that although adolescents have almost universal knowledge about contraceptive methods, only 15 percent are currently using any method of contraception. The corresponding figures for the adults and for the nation as a whole are 34.4 percent and 31.4 percent, respectively. Among the individual methods currently used by the adolescents, the pill appears as the most popular method, followed by safe period. A substantial proportion of the adolescents were found to rely on the traditional methods of contraception. Among the socio-economic variables (as revealed by the logistic regression analysis), respondents' education, participation in the family planning decision, visit by family planning workers, region of residence, husband's occupation and possession of electricity in the household appear as the most significant factors determining the current use of contraception among the adolescents.

Adolescent↗
PubMed1985

Fertility, sterilization, and population growth in Shanti Nagar, India: a longitudinal ethnographic approach.

The results of the 1981 Indian census showed a slight increase in the rate of population growth despite an energetic governmental campaign to reduce fertility, the growing use of contraception, a substantial number of sterilized persons, and a declining birthrate. The longitudinal ethnographic analysis of population data from Shanti Nagar dating from the 1950s and the 1970s suggests that the growth rate of the population might be better understood if analytical emphasis were to be shifted somewhat from birth and death rates to survivorship, that is, the average number of living children per mother, thus focusing attention on the family, the social unit in which the decisions are made that give rise to national demographic rates and averages. Currently, the principle fertility decision that a Shanti Nagar couple must make is whether to undergo sterilization and how many children are deemed necessary before taking this step. Analysis of the Shanti Nagar data shows that women of completed fertility in the 1970s had more living children than comparable women in the 1950s, and that even the sterilized couples of the 1970s had only slightly fewer children than the almost entirely noncontracepting women of the 1950s. Although the age of women at their own (or their husbands') sterilization is falling and the operation takes place after fewer children than formerly, the average sterilized couple nonetheless has more than 4 children instead of the 2 or 3 that the Government of India prefers. An analysis of the relationship to fertility of various modernization variables, such as urbanization and enhanced economic status, fails to show any consistent correlation of such variables with reduced fertility. School attendance by females is perhaps the most promising of the modernization veriables, but its effect is somewhat ambiguous and relatively weak until women achieve the college level. Current trends suggest that soon after 2025, India may surpass China as the world's most populous nation.

Asia↗
PubMed1990

Socio-demographic and gynaecological variables of maternal mortality in a Kenyan subdistrict: January 1981-September 1988.

A study on institutional maternal mortality in Thika subdistrict is presented for the period January 1981 through September 1988. There were 86,248 live births in the various government and private institutions in the sub-district and 164 maternal deaths, giving a maternal mortality rate of 190/100,000. The various associated socio-demographic factors are analysed.

Adolescent↗
PubMed1990

Determinants of fertility control in Korea.

The objective of this study is to examine the socioeconomic and intervening determinants of fertility control in Korea. The conceptual framework applied here is based on the synthesis framework of fertility control developed by Easterlin and Crimmins. The data came from the 1974 Korean National Family Survey, which was conducted as part of the World Fertility Survey. The study focuses on the relative importance of the socioeconomic factors and intervening variables in the determination of fertility control. The most interesting finding is that there are only small differentials in fertility control by socioeconomic factors. The analysis emphasizes the importance of examining the determinants of fertility control in terms of the intervening variables, which include the components of natural fertility, desired family size, and costs of fertility control. These intervening variables provide general support for the theoretical predictions. Moreover, most of the coefficients for these variables are statistically significant at the .05 level. The analysis also shows that motivation for fertility control is an important factor in determining use of fertility control.

Age Factors↗
PubMed1991

Proximate determinants of child mortality in Liberia.

The study looks at the effects of maternal sociodemographic characteristics and the quality of the environment on child survival through two intervening variables, breast-feeding and prenatal care. A linear structural equation modelling approach was used to examine infant and child survival based on a weighted sample of 5180 Liberian children aged 0-5 years. The findings confirm previous studies, but also reveal complex relationships of the role of education, maternal age and breast-feeding in enhancing child survival.

Breast Feeding↗
PubMed1990

Contraceptive behavior among sexually active Hispanic adolescents.

The purpose of this study was to examine those factors associated with the contraceptive behavior of a national representative sample of Hispanic female adolescents. The subjects included all (n = 85) unmarried, sexually active Hispanic women, aged 15 to 19, from the 1982 National Survey of Family Growth. Contraceptive behavior was measured on a normalized scale, ranging from oral contraceptives to no contraception. Mexican/American and Central/South American background females were more likely (p less than 0.031) to use effective birth control than Puerto Rican, Cuban, and other Hispanic background subjects. Twenty additional social, behavioral, and demographic variables were found to be significantly associated (p less than 0.05) with contraceptive behavior. Based on multiple regression analysis, seven of these variables were found to explain 62% (p less than 0.0001) of the variation in the contraceptive behavior of this sample. Poorer contraceptive behavior was associated with noncompliance with the initial birth control method used (33.8%), lower coital frequency (8.3%), older postmenarchial age (5.7%), failure to use birth control at first coitus (4.6%), fewer years dating (4.0%), lower frequency of church attendance (3.3%), and never having experienced a pregnancy scare (2.0%). These findings suggest that the contraceptive behavior of Hispanic female adolescents is a dynamic process that can be understood in the context of previous sexual and contraceptive behavior.

Adolescent↗
PubMed1979

Application of discriminant analysis to level of performance of alcoholics and nonalcoholics on Wechsler-Bellevue and Halstead-Reitan subtests.

Investigated the utility of subtests from the Wechsler-Bellevue Intelligence Scale and the Halstead-Reitan Neuropsychological Test Battery to differentiate between alcoholics and nonalcoholics (N = 76). Analyses of variance indicated that the alcoholics were more impaired than nonalcoholics. It was found that the Wechsler-Bellevue Performance subtests were more discriminative than were Verbal subtests, with performance on the Halstead-Reitan variables being intermediate. The nine measures that differentiated most significantly between groups were subjected to a stepwise multivariate discriminant analysis. The resulting function correctly classified Ss with an overall accuracy of 74.7%. It was found that the Block Design subtest was the best single discriminator. The findings were discussed in relationship to previous findings and with respect to general issues of clinical neuropsychological assessment.

Alcoholism↗
PubMed2001

The effect of low temperature and fasting during the winter on metabolic stores and endocrine physiology (insulin, insulin-like growth factor-I, and thyroxine) of coho salmon, Oncorhynchus kisutch.

The objective of this study was to examine the effect of winter feeding and fasting at both high (10 degrees ) and low (2.5 degrees ) temperatures on growth, metabolic stores, and endocrinology of coho salmon. Treatments were as follows: warm-fed, warm-not fed, cold-fed, and cold-not fed during the winter (January-February). The following parameters were measured: length, weight, whole body lipid, liver glycogen, hepatosomatic index, and plasma levels of insulin, insulin-like growth factor-I (IGF-I), and thyroxine (T4). Warm-fed fish grew continuously throughout the experiment from 21.5 +/- 0.3 to 43.4 +/- 1.4 g and were larger than fish in the other treatments. Fish in all other treatments grew from 21.5 +/- 0.3 to approximately 32 g and showed depressed growth during January and February. During the winter, liver glycogen, hepatosomatic index, plasma insulin, and IGF-I were highly influenced by manipulations in rearing conditions, whereas whole body lipid and plasma T4 were less affected. Plasma insulin levels fluctuated dramatically (from 2 to 7 ng/ml) in the two cold-acclimated groups shortly after the change in temperature. In general, the plasma insulin levels of the warm-fed fish were the highest (8-9 ng/ml), those of the warm-not fed fish were the lowest (2-5 ng/ml), and those of the two cold-acclimated groups were more variable but intermediate. In contrast, plasma IGF-I levels showed a decline with temperature decrease (from 9 to 5 ng/ml) and more gradual changes than insulin with the change in feeding. The highest plasma IGF-I levels were found in the warm-fed fish (10-15 ng/ml), the lowest levels were in the cold-not fed fish (4-5 ng/ml), and those of the warm-not fed and cold-fed fish were intermediate. During the treatment period the T4 levels were relatively unaffected by manipulations in feeding and temperature compared with either insulin or IGF-I. These data suggest that the insulin, IGF-I, and thyroid axes are differentially regulated under changing seasonal and/or environmental conditions in yearling salmon.

Animals↗
PubMed1995

Specific compositional patterns of synonymous positions in homologous mammalian genes.

All 69 homologous coding sequences that are currently available in four mammalian orders were aligned and the synonymous (ie., third) positions of quartet (fourfold degenerate) codons were divided into three classes (that will be called conserved, intermediate, and variable), according to whether they show no change, one change, and more than one change, respectively. The three classes were analyzed in their compositional patterns. In the majority of GC-rich genes, the three classes of positions (but especially conserved positions) exhibited significantly different base compositions compared to expectations based on a "random" substitution process from the "ancestral" (consensus) sequence to the present-day (actual) sequences. Significant differences were rare in GC-poor genes. An analysis of the present results indicates that natural selection plays a role in the synonymous nucleotide substitution process, especially in GC-rich genes which represent the vast majority of mammalian genes.

Animals↗
PubMed1990

Socioeconomic determinants of fertility in China: a microeconometric analysis.

"This paper reports the first set of estimates of the socioeconomic determinants of fertility in China using micro-data available from China's 1985 In-Depth Fertility Survey. Based on existing microeconomic theories of fertility, an econometric model was specified and estimated. The results indicate that even after age, marriage duration and child mortality are taken into account, education level of the woman, occupational status of the husband, the place of former and current residence, sex preference for boys, durable goods ownership, and family structure affect fertility."

Age Factors↗
PubMed1977

Polymorphism of red cell glyoxalase 1. With special reference to South and Southeast Asia and Oceania.

Glyoxalase polymorphism has been studied in 7296 persons from populations in South Asia, Southeast Asia, Oceania, Iran and Colombia. The GLO frequencies are very low in most of Oceania, including Australia, somewhat higher in Southeast Asia, and intermediate though variable in India. In Iran the GLO frequency is similar to that in Europe. The value for the single amerindian group in Colombia is nearly 30%.

Asia, Southeastern↗
PubMed1987

Exercise training induces transitions of myosin isoform subunits within histochemically typed human muscle fibres.

Fibre type composition based on histochemical myosin ATPase reaction was studied in cross sections of biopsies from the vastus lateralis muscle of men. In addition, protein composition as well as peptide patterns of isolated myosin heavy chains were examined in batches of individually classified fibres from the same biopsies. High intensity endurance training during 8 weeks induces significant decreases by 31-70% of the type IIB fibre population in 3 of 4 subjects (in one case no change was observed). These decreases were offset by corresponding increases in either type I or type IIA fibres with the type IIC fibres remaining always below 3%. A total of 13 professional cyclists with training periods over several years have a 20 times lower content of type IIB fibres than 4 sedentary controls and a concomitant high content of 80% of type I fibres. The content of type I and type IIB fibres of 8 sprinter athletes did almost not differ from that of controls. Thus the type IIB fibres respond most sensitively with a decrease to aerobic endurance training. Since both type IIA and IIB fibres were identical in protein composition containing the same fast variety of myosin light chains and heavy chains as well as troponin-I, their interconversion could not be seen at the molecular level. However, the slow variety of myosin light chains and of troponin-I started accumulating after 8 weeks of training in type IIA fibres. Furthermore, the myosin heavy chain isoform started shifting by producing new peptide patterns that resemble the digestion pattern of slow myosin heavy chains in fibres which still classified as type IIA. These changes on the molecular level in type IIA fibres mark the beginning of their transition over the intermediate and variable type IIC fibres, towards the slow type I fibre.

Adult↗
PubMed1992

Correlations between densitometry of red-free photographs and reflectometry with the scanning laser ophthalmoscope in normal subjects and glaucoma patients.

OBJECTIVE: To compare image measurements of the retina produced by scanning laser ophthalmoscopy with those from red-free photographs (RFP) of the nerve fibre layer. SUBJECTS: The left eyes of 23 subjects (10 normal, 7 glaucoma suspect and 6 glaucomatous) were included in this study. METHOD: All the eyes were photographed using standard red-free photography, and images of the retina were digitised directly from the SLO. RESULTS: The correlation coefficient for all except three subjects was > 0.45, and the probability (p) that R = 0 was < 0.05 in all but 5 eyes. CONCLUSIONS: The data indicate that variations in retinal surface reflectivity as measured by the SLO are similar to those recorded on negative film during RFP. This further suggests that the SLO can be useful for making objective measurements of the RNFL, without the intermediate and variable steps of photography.

Densitometry↗