PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Migration, Internal”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 595 records · Page 33Linked to original sources
PubMed1983

Migration between the United States and Canada: a study of labour market adjustment.

"... The main purpose of this study is to examine population flows between Canada and the United States [from mid-1947 to mid-1972] in order to investigate the degree to which labour market adjustment is aided by such movements. [The author considers] several functional forms of the migration relationship in an attempt to empirically determine how the decision to migrate is formed. [He also compares the] results with those obtained by Courchene...for Canadian interprovincial migration in an effort to compare the effects of international and internal migration on labour market adjustment." It is found that "migration between the United States and Canada over the post-war period is an economic variable. In fact, [a] simple model employing differences in income levels and unemployment rates has been able to explain nearly ninety-five per cent of the variation in the migration rate." The author also notes that "although migration between Canada and the United States does occur in such a way as to aid labour market adjustment, it is not as efficient as internal migration." (summary in FRE, SPA)

Americas↗
PubMed1988

Age patterns of elderly migration: an international comparison.

Age-specific rates of migration exhibit remarkably persistent regularities in age profile. These regularities seem to hold all over the world and across time. This article identifies some of the principal antecedents of such regularities, focusing especially on the age patterns of migration exhibited by the elderly. It examines the differentials introduced by gender, distance, and marital status.

Aged↗
PubMed2006

p38 kinase regulates epidermal growth factor receptor downregulation and cellular migration.

Internalization and proteolytic degradation of epidermal growth factor (EGF) receptor (R) following ligand binding is an important mechanism for regulating EGF-stimulated signals. Using pharmacological and RNA interference inhibition of p38 mitogen-activated protein kinase, we show that p38 is required for efficient EGF-induced EGFR destruction but not internalization. In the absence of p38 activity, EGF fails to stimulate the ubiquitin ligase Cbl or ubiquitinylation of EGFR, and internalized EGFR accumulates in intracellular vesicles containing caveolin-1. These effects are accompanied by loss of EGFR phosphorylation on Y1045, a phosphorylation site required for Cbl activation. Furthermore, similar to cells treated with p38 inhibitors, intestinal epithelial cells expressing Y1045F EGFR mutants show increased proliferation but not migration in response to EGF, thus uncoupling these biological responses. Together these data position p38 as a modulator of ligand-stimulated EGFR processing and demonstrate that this processing has a profound impact on the cellular outcome of EGFR signaling.

Animals↗
PubMed1995

Theories of international labor migration: an overview.

"Emigration pressures are primarily the result of increasing inequalities between countries which, in turn, are the result of factors internal to less developed countries and their relations with developed countries. Both micro (neoclassical) and macrostructural theories of migration are reviewed. It is argued that the neoclassical theory of migration is often unjustly criticized and is sufficiently robust to incorporate those structural considerations which are at the core of macrostructural theories. Moreover, the neoclassical theory, with slight modification, can incorporate the ¿new economics of migration.' The major empirical problem confronting models of international labor migration is that migration flows are constrained by immigration policy. This policy, in turn, is influenced by various special interest groups. The direction and form of migration flows is conditioned by contemporary and historical relationships between source and destination countries."

Demography↗
PubMed1991

Migration and population ageing: a case of Poland.

The effect of internal migration on population aging in Poland is assessed, using data for the years 1950-1988. Trends are presented for the country as a whole, by individual voivodship, and for rural regions that have experienced rapid depopulation. The authors conclude that "internal migrations have no direct influence on the population's ageing process, and [are] insignificant. The influence grows in the spatial perspective; it becomes strongest in the case of migrations between urban and rural areas. Its intensity is best revealed in the...depopulation in rural areas."

Demography↗
PubMed1988

Migration trends and regional labour market change in Poland.

The author examines internal migration and its relation to economic conditions in Poland during the period since World War II. The "basic facets of internal migration in Poland, as they prevailed over the last decades, will be summarized in Section 2 and [compared] with the most recent mobility trends. Section 3 will focus on migration flows within and among 49 regions over the 1975-1983 period while taking account of changing industrial employment levels in individual regions. Alternative interpretations of observed migration patterns will be sought in Section 4. Preliminary conclusions and some further questions will be listed in Section 5."

Demography↗
PubMed1981

Health manpower migration in the Americas.

This paper discusses the international migration of physicians and nurses in the Americas in terms of dimensions, directions, salient characteristics of migrants, and possible consequences of migratory flow. The paper is based on information from a previous multinational study on the international migration of physicians and nurses, carried out by the World Health Organization; the study is both descriptive of this phenomenon and prescriptive of the type of measures that may be needed to control it. There is sufficient evidence to substantiate the order of magnitude of the outflow of medical and nursing manpower from Central and South American countries to provide a guide to policy and action. The information for most countries is, however, incomplete and inaccurate and, consequently, the net flow remains to be determined. A large part of the migration appears to be due to the imbalance between the supply of, and the effective economic demand for, physicians' and nurses' services. Perhaps the most important finding is that countries which produce far more physicians and nurses than they can economically afford to employ become donors of such manpower, and those which produce fewer than they can afford become recipients. Almost all other factors either derive from or are secondary to the economic factor. The paper suggests some alternative policy issues that countries having excessive migration of medical and nursing manpower may consider to control the flows. Among these, the most important is the formulation of realistic health manpower and educational policies and plans.

Central America↗
PubMed1999

Phosducin, beta-arrestin and opioid receptor migration.

Internalization of G protein-coupled opioid receptors depends on multiple criteria, including the affinity of drugs to their receptors and the state of the receptor-G protein interaction. Most recent studies reveal that cytosolic components like phosducin and arrestin interfere with receptor internalization, that is phosducin impairs receptor phosphorylation and arrestin enhances endocytosis by uncoupling the receptor from its G protein. This study was designed to examine the mutual effect phosducin and arrestin exert on receptor endocytosis. Neuronal NG 108-15 hybrid cells transiently expressing the mu-opioid receptor, which has been fused to green fluorescence protein, were employed to study internalization of the fluorescent mu-opioid receptor construct in living cells by means of confocal laser scanning microscopy. Fluorescent mu-opioid receptors were detected in drug-naive cells both at the cell membrane and at cell surface protrusions, most likely filopodia, microspikes and retraction fibres. The opioid receptors present in the cell membrane internalize upon etorphine (1 nM) exposure, a process clearly blocked in cells overexpressing phosducin. However, coexpression of both phosducin and beta-arrestin 1 reverses this blockade. In contrast to etorphine, morphine fails to internalize mu-receptors expressed in NG 108-15 cells. When arrestin is overexpressed in these cells, morphine gains the ability to induce endocytosis, and this process is left unaffected by phosducin. The findings suggest that endocytosis of activated mu-opioid receptors primarily depends on arrestin-triggered uncoupling of the receptor from its G protein complex. Drug-induced receptor phosphorylation appears of subordinate significance for receptor internalization.

Analgesics, Opioid↗
PubMed1997

Direct detection of the internal acyl migration reactions of benzoic acid 1-O-acylglucuronide by 13C-labeling and nuclear magnetic resonance spectroscopy.

1-O-Acyl-beta-D-glucopyranuronates can undergo irreversible binding to proteins mainly through internal acyl migration reactions, which may have toxicological significance. A new method based on the 13C-labeling and nuclear magnetic resonance (NMR) spectroscopy has been developed to study the reactivity of the 1-O-acyl-beta-D-glucopyranuronate of benzoic acid. In phosphate buffer (pH 7.4) solution at 37 degrees C, the glucuronide showed apparent first-order degradation kinetics (T1/2, 125 min), and concurrent and sequential appearance of 2-, 3- and 4-O-acyl isomers as both alpha- and beta-anomers was observed. The isomeric glucuronides were identified by two-dimensional NMR of the reaction mixture. The direct approach using 13C-labeling and NMR could also provide insights into the reactivities of other labile drug acylglucuronides and their isomeric glucuronides.

Benzoates↗
PubMed1988

Changing patterns of migration in the Adriatic region.

International migration in the Adriatic countries of Albania, Greece, Italy, San Marino, and Yugoslavia is briefly examined using data from official and other published sources. The main types of migratory movements identified by the author within the region are "1) economically motivated migration (legal and clandestine); 2) immigration of refugees for resettlement; 3) immigration with the scope of final resettlement in a third country (transit movements); [and] 4) return migration by former emigrants."

Albania↗
PubMed1991

Migration: gains or losses?

The author examines the question of who gains and who loses from international migration. He attempts to show that "on the basis of generally accepted assumptions, some definite propositions concerning international migration can be rigorously and unambiguously established for the countries of origin and destination as well as for both countries taken together and hence...for the world as a whole." In general economic terms, the author concludes that both sending and receiving countries benefit from such migration.

Demography↗
PubMedDate not supplied

[Migrating women: Mexican women in the United States].

"This analysis considers some aspects of the international migration of Mexican women, seen under the light of two recent statistical sources: the [U.S.] 1990 census and the 1993-1994... International Migration Survey at the Mexican Northern Border. The joint analysis of migrations and migrant inventories reveals the hidden scope of feminine exile, as well as some of its peculiarities, and offers numerical answers to two questions: How does sex differentiate Mexican immigrants in the United States? How does the migration affect work, marriage, child-bearing, etc. of Mexican women? The results suggest the need to address migration no longer as an action of individuals, but of families (most immigrants are married), and to place the mother or the wife at the gravity center of the household migratory space." (SUMMARY IN ENG)

Americas↗
PubMedDate not supplied

Migration patterns in India.

"The chief objective of the present paper is to comprehend the broad spatial patterns of internal migrations in India." Aspects considered include data constraints, the magnitude of internal migration, interstate migration, migration to rural and to urban destinations, spatial patterns, and areas of origin and destination.

Asia↗
PubMed1995

[Family reunification and family formation migration strongly decreased].

"Statistics on international migration in the Netherlands do not make a distinction by reason of migration, e.g. family reunification and family formation. Because of the need for information on these types of migration, estimates were made based on demographic characteristics. The estimates show that the number of family reunionists was stable between 1987 and 1991....Recently, the Dutch policy on immigration has become more restrictive. Although information with respect to more recent years is largely lacking, tentative estimates suggest that the 1994 number of family reunionists and family forming immigrants combined has shown a strong decrease compared to 1991." (SUMMARY IN ENG)

Demography↗
PubMed1995

South-North migration. The case of Spain.

"International migrations caused by socio-economic and demographic reasons, especially from underdeveloped countries to the rich and prosperous areas of the globe are discussed with the focus on Western Europe and particularly on Maghrebi immigration to Spain. Emigration of the people from a backward region even increases the deterioration of [the] local economy, provoking stagnation and inflation. Therefore emigration only can not be seen as an economic take-off for sustained economic development over the frontier areas between developed and depressed territories. Related social questions as well as economic, religious and political may add factors affecting the structural balance of the societies concerned."

Acculturation↗
PubMed1996

European economic restructuring: demographic responses and feedbacks.

The relationship between economic restructuring in Europe and various aspects of demographic change, such as demographic aging and fertility decline, is examined. The focus is on changes in the labor market. "Changing employment conditions--the growth of the secondary labour market, the flexibilization of labour demand and increasingly also of supply, growing female labour force participation rates, generally high ethnic minority unemployment--reflect different aspects of the transition from the Fordist to the postFordist regime as well as changing demographic and life-style influences. Together they have deeply transformed the European landscape of employment and unemployment. The specific role of international migration is also analysed and it is seen to have fundamentally altered between the Fordist and postFordist eras. Less clear to interpret are changing internal migration patterns: has counterurbanization stopped in response to restructuring and integration and is a new postFordist population map unfolding? The paper concludes by evaluating the nature of the relationship between economic restructuring and population trends and identifying pointers for future research."

Birth Rate↗