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PubMed1992

Support exchange patterns of the elderly in the Republic of Korea.

The authors examine support of the elderly in South Korea, with a focus on the future implications of demographic aging. "Owing to socio-economic development in the Republic of Korea and the country's success in reducing mortality and fertility, the proportion and number of elderly in the population is rapidly rising. Co-residence with adult children is the most important pattern of support for the elderly. But the elderly also contribute support in the form of financial and material assistance as well as services such as care of grandchildren. The article concludes that, because of the rapid increase in the absolute size of the elderly population, government services need to be expanded to assist in providing care for the elderly."

Adult↗
PubMed1990

[Permanent migration of the population of Ciechanow during the period 1976-1987].

Trends in migration to the city of Ciechanow, Poland, from 1976 to 1987 are analyzed. The author finds that a "majority of population settling in this centre came from rural areas, and the percent share of this subpopulation in the total number of migrants grew from 62.8% in 1976 to over 80% in 1987." Consideration is given to changes in age distribution and family characteristics among migrants. (SUMMARY IN ENG AND RUS)

Age Distribution↗
PubMed1994

[Uncertain prognosis of European family evolution].

The author discusses past and future changes in the family in Europe. "During the years 1965-1985 demographic characteristics of...Western Europe indicate decline of fertility, nuptiality, growth of the number of divorces as well as growth of illegitimate deliveries....Family sociologists consider the present changes as [a] phenomenon of transformation of the Western-European family." (SUMMARY IN ENG AND RUS)

Demography↗
PubMed1993

Trend of change in various kinds of nuclear families in China since the 1980s.

"By using the latest data of 1% sampled data made in the Fourth Population Survey in 1990 and 1 [per 1,000], sampled data made in the Third Population Survey in 1982, we have attempted an analysis...of the trend of change of proportion among nuclear parents-families, separated-parents, single-parent and interval-generation families, as well as two-, three- and four-generation lineal and joint families in China during the 1980s, both as a nation and in all provinces, municipalities directly under the central government and autonomous regions."

Asia↗
PubMed1994

[Children in single-parent families, yesterday and today].

"This study, conducted from the point of view of the children, compares cohorts from the time of New France [Quebec] with those of Canada today, showing that single parenthood is not a new phenomenon. The types of single parenthood, however, are quite different. The colonial model of the traditional family has given way to a variety of family situations. As well, while death was the only cause of single parenthood during the colonial era, separations today are essentially based on some sort of decision. The psychological repercussions of losing a parent are thus completely different." (SUMMARY IN ENG AND SPA)

Adolescent↗
PubMed1986

An experimental analysis of the origins of somatostatin-like immunoreactivity in the dentate gyrus of the rat.

In previous studies, fibers demonstrating somatostatin-like immunoreactivity were observed in the outer half of the molecular layer of the dentate gyrus in the rat and monkey. They occupy the same region as those of the perforant pathway that originates in the entorhinal cortex. Numerous somatostatin immunoreactive neuronal cell bodies were also observed in the hilar region, though stained axonal profiles could not be followed from these cells into the molecular layer. In the present study, several experimental procedures were employed to determine the origin of the somatostatin-positive fibers in the molecular layer. Transection of the perforant path fibers resulted in such characteristic changes as shrinkage of the molecular layer and sprouting of AChE-positive fibers. There was no apparent decrease, however, in the density of somatostatin-positive fibers. In fact, since the stained fibers occupied a narrower band in the shrunken molecular layer, their density appeared greater. Injections of kainic acid into the hilar region produced a lesion of hilar neurons, including those positive for somatostatin. In the region of cell loss, there was a marked reduction of somatostatin-immunoreactive fibers in the ipsilateral molecular layer, with no detectable changes in the homotopic contralateral molecular layer. The distribution of AChE fibers, which presumably have an extrinsic origin, was not altered by the treatment. In a final series of experiments, the retrograde tracer wheat germ agglutinin-horseradish peroxidase (WGA-HRP) was injected into the hilar region and sections were prepared for the simultaneous demonstration of the tracer and of somatostatin-like immunoreactivity. Somatostatin-positive neurons demonstrating WGA-HRP reaction product were observed primarily in the ipsilateral hilar region, but a few double-labeled cells were also seen in the same area of the contralateral side. These studies indicate that a population of intrinsic neurons located in the polymorphic layer of the dentate gyrus projects to the outer half of the ipsilateral molecular layer. A similar, but very much smaller, projection also extends to the contralateral dentate gyrus. Taken together, these projections appear to account for much of the somatostatin-like immunoreactivity in the molecular layer of the dentate gyrus.

Animals↗
PubMed1988

Age related changes in the human plastron: a roentgenographic and morphologic study.

Characteristic changes that can be demonstrated on roentgenograms occur with increasing age in the plastron (chest plate) of humans. These alterations include progressive ossification in the costal cartilages (located characteristically in the sternal rib end, centrichondrally, and peristernally--often with sex and age distinctive patterns), maturation of the newly formed bone with trabeculation formation, loss of the smooth contour of the costo-manubrial junction, cupping of rib ends, osteoporotic changes, and arthritic changes in the sternal head of the clavicles. The sequence of development of these alterations has been examined by X-ray of 1965 cadavers of 15 years of age or over and correlated with the gross bone and cartilage morphology changes in many cases. This technique allows for age determination within 5 years of real age in 55% of cadavers and within 25% of real age in 95% of all cadavers. The greatest departures from real age are in the over-60-year groups. The same roentgenograms can allow for correct sex prediction in 99% of the population.

Adolescent↗
PubMed1985

Differential sensitivity of human breast cancer cell lines to the growth-inhibitory effects of tamoxifen.

In eight estrogen receptor (ER)-positive breast cancer cell lines (including three sublines of MCF-7) and five ER-negative breast lines, the action of the nonsteroidal antiestrogen, tamoxifen, was studied, and the concentrations of ER and antiestrogen binding site were measured. The concentration of antiestrogen binding site was significantly [P less than 0.005] greater in ER-positive cells [236,600 +/- 29,900 (SE) sites/cell] than in ER-negative cell lines [66,600 +/- 16,800 sites/cell]. In ER-positive cell lines, a cell cycle phase-specific growth-inhibitory effect, 20% inhibitory dose less than 0.1 to 1.0 microM, was seen which was shown for some representative cell lines to be estrogen reversible. Within this group of cell lines, the degree of tamoxifen-induced inhibition of growth correlated with control population doubling time, but not ER or antiestrogen binding site concentration. The changes in cell cycle kinetic parameters characteristic of all ER-positive lines were a decrease in percentage of S-phase cells and a corresponding increase in percentage of G0-G1 cells. In all cell lines, 5 to 12.5 microM tamoxifen caused cytotoxicity, and this was shown to be estrogen-irreversible in 3 representative cell lines; moreover, estradiol synergistically enhanced the cytotoxic effects of tamoxifen under some experimental conditions. The cell cycle effects of tamoxifen in three ER-negative cell lines (Hs0578T, MDA-MB-231, MDA-MB-330) were decreased proportions of G0-G1 cells with an increase in percentages of S and G2+M cells. These results implied that the mechanism of tamoxifen cytotoxicity may differ in ER-positive and ER-negative breast cancer cells. However, although the ER-negative BT-20 line was much less sensitive to tamoxifen than were the ER-positive cells, growth inhibition and cytotoxicity in this line were associated with a slight decrease in percentage of S-phase cells. These results confirm that ER-positive breast cancer cells are more sensitive (4- to greater than 75-fold) than ER-negative breast cells to the growth-inhibitory effects of tamoxifen and demonstrate that, in all ER-positive cells, growth inhibition and cytotoxicity are accompanied by characteristic changes in cell cycle kinetic parameters. In contrast, different mechanisms may be involved in the effects of tamoxifen on different ER-negative cell lines.

Breast Neoplasms↗
PubMed1985

[Effect of hypobaric hypoxia on motor behavior in rats].

Hypobaric hypoxic exposure for 18 h (pO2 8.7 kPa) effects characteristic changes of motoric behaviour in adult rats. We observed a posthypoxic increase of spontaneous locomotion and of open-field activity. 24 h after hypoxic exposure the locomotion stimulated by dopaminergic agonists apomorphine or amphetamine was strengthened. Dopaminergic nuclei showed a different sensitivity to unilaterally applied dopamine after hypoxic exposure. Rotational behaviour was facilitated in the nucleus accumbens but significantly decreased in the substantia nigra. In the nucleus caudatoputamen we could not prove changes in comparison to controls. These results indicate that central dopaminergic processes are influenced by hypobaric hypoxic exposure. Besides the sensitization of dopaminergic receptor populations these changes of motoric behaviour may be connected with interactions between different transmitter systems or displacement of central regulation systems.

Amphetamine↗
PubMed1994

[Comparison of four different methods for respiratory determination of the anaerobic threshold in normal people, and heart- and lung patients].

We analyzed 128 cardiopulmonary exercise tests (CPX), performed in normal subjects (n = 31), in patients with coronary artery disease (n = 41), with chronic heart failure before (n = 14) and after (n = 14) application of oral PDE-inhibitors and in patients with HIV-infection on a bicycle-ergometer in semi-supine position using a ramp-program (dependent on study-population with 15, 20 or 35 Watt/min increases) with respect to the ability to determine the respiratory anaerobic threshold non-invasively, using the main criteria described by Wasserman et al.: the V-slope-method according to Beaver, the increase of the ventilatory equivalent for O2 (VE/VO2), the increase of the end-tidal PO2 (PETO2) and the increase of the respiratory quotient (RQ) during exercise. In the different study-populations we calculated the detection rates of the AT for each criteria separately. The typical changes in the end-tidal PO2 (124/128 = 96.9%) and the V-slope-method (119/128 = 92.9%) were the most reliable parameters to detect the anaerobic threshold. The characteristic changes of the ventilatory equivalent for O2 (VE/VO2) and of the respiratory quotient (RQ) we found in 100/128 (= 78.1%) and in 107/128 (= 83.6%) of the tests respectively. 86/128 tests (67.2%) showed typical changes in all four mentioned criteria. In another 24/128 tests (19.8%) three of four criteria were fulfilled. Therefore, our investigations showed that in 110/128 cases (85.9%) the AT could be determined by typical changes by means of at least three of the four described parameters. In 15/128 (11.7%) tests only two of four criteria were fulfilled.(ABSTRACT TRUNCATED AT 250 WORDS)

Anaerobic Threshold↗