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PubMed1986

Mexican immigration and health care: a political economy perspective.

This paper examines the case of Mexican immigrants in the United States and their access to medical services within a political economy of health framework. Such an approach stresses that the provision of health care is independent of health factors per se and that access to health care is not equally distributed throughout a population. The first section reviews the three major concepts influencing medical anthropologists working within a political economy framework: the social origins of illness; the allocation of health resources; and fieldwork in Third World countries. The analysis then focuses upon the reasons for limiting immigrants' access to health care, followed by an examination of the socioeconomic characteristics of Mexican immigrants, including an undocumented immigration status, which limit their access to health care. Finally, the consequences of limited access to health services are suggested, including a low utilization of preventive health services resulting from the high cost of care combined with the immigrants' generally low income, lack of medical insurance and fear of using U.S. health services.

California↗
PubMed2005

Effects of TIPS on liver perfusion measured by dynamic CT.

OBJECTIVE: Our aim was to measure the arterial, portal venous, and total perfusion of the liver parenchyma with dynamic, single-section CT in patients with liver cirrhosis before and after transjugular intrahepatic portosystemic shunt (TIPS) placement and to compare the results with normal values. SUBJECTS AND METHODS: Perfusion of the liver parenchyma was measured in 24 healthy volunteers and 41 patients with liver cirrhosis using dynamic single-section CT. Seventeen patients underwent TIPS placement, and CT measurements were repeated within 7 days. CT scans were obtained at a single level comprising the liver, spleen, aorta, and portal vein. Scans were obtained over a period of 88 sec (one baseline scan followed by 16 scans every 2 sec and eight scans every 7 sec) beginning with the injection of a contrast agent bolus (40 mL at 10 mL/sec). Parenchymal and vascular contrast enhancement was measured with regions of interest, and time-density curves were obtained. These data were processed with a pharmaco-dynamic fitting program (TopFit), and the arterial and portal venous component and the total perfusion of the hepatic parenchyma were calculated (milliliters of perfusion per minute per 100 mL of tissue). RESULTS: Mean normal values for hepatic arterial, portal venous, and total perfusion were 20, 102, and 122 mL/min per 100 mL, respectively. In patients with cirrhosis before TIPS, mean hepatic arterial, portal venous, and total perfusion was 28, 63, and 91 mL/min per 100 mL, respectively, which was statistically significant for all values (p <0.05). After TIPS, hepatic perfusion increased to a mean value of 48, 65, 113 mL/min per 100 mL for arterial (p <0.01), portal venous, and total (p=0.011) perfusion, respectively. CONCLUSION: In patients with cirrhosis, the hepatic arterial perfusion increased, whereas portal venous and total perfusion decreased compared with that of healthy volunteers. TIPS placement caused a statistically significant increase of the hepatic arterial and total hepatic perfusion. The portal venous parenchymal perfusion remained unchanged.

Adult↗
PubMed1996

Maternal mortality in Malaysia 1991-1992: the paradox of increased rates.

"This paper aims to show that the establishment of a better data collection and reporting system in Malaysia since 1991 has led to an apparent increase in the maternal mortality ratio.... Because of improved surveillance, the maternal mortality ratio may continue to appear to rise for a few years but should decline after that reflecting the improvement in the health status and service delivery in Malaysia."

Asia↗
PubMedDate not supplied

Community-based rehabilitation in the Philippines.

Rehabilitation in the Philippines has in the past been based on the Western model, with an emphasis on hospital departments located in the major cities. This approach is inappropriate for the majority of disabled people in the Republic as 70% of the population live in rural areas. A community-based programme was devised using local volunteers who had simple training. These volunteers can identify and support disabled people in their own villages, avoiding long journeys and expensive institutional care.

Community Health Services↗
PubMed2001

Utah Virtual Lab: JAVA interactivity for teaching science and statistics on line.

The Utah on-line Virtual Lab is a JAVA program run dynamically off a database. It is embedded in StatCenter (www.psych.utah.edu/learn/statsampler.html), an on-line collection of tools and text for teaching and learning statistics. Instructors author a statistical virtual reality that simulates theories and data in a specific research focus area by defining independent, predictor, and dependent variables and the relations among them. Students work in an on-line virtual environment to discover the principles of this simulated reality: They go to a library, read theoretical overviews and scientific puzzles, and then go to a lab, design a study, collect and analyze data, and write a report. Each student's design and data analysis decisions are computer-graded and recorded in a database; the written research report can be read by the instructor or by other students in peer groups simulating scientific conventions.

Humans↗
PubMed1992

[[Comparison of mortality rates of elderly people in China and Japan]].

"The mortality rates and causes of death among elderly people aged sixty five and over were compared between China and Japan. The data used for comparison was China's 1990 and Japan's 1990 vital statistics. It appears that the mortality rate in China was higher than Japan. Comparing the causes of death, it was found that the death rates involving cerebrovascular diseases, malignant neoplasms and heart diseases in urban districts of China [were] higher than those in Japan. Also the death rate of people with bronchitis in rural districts was significantly higher in China.... The differences in the medical systems and life styles in China and Japan were suspected as the reasons for the differences of death rates and causes of death...." (SUMMARY IN ENG)

Adult↗
PubMed1999

The relevance of ethnic monitoring in the experience of Haringey Healthcare NHS trust community family planning clinics.

Ethnic monitoring of all new and first attenders in the year to community family planning clinics was carried out by means of an anonymous questionnaire during April to June 1997 inclusive to ascertain whether ethnic minority women attend family planning clinics. A 73 per cent response rate (2664 questionnaires) was obtained. The results showed that women came from a wide variety of ethnic groups and from almost every country in the world. Those of UK European origin were underrepresented. For 28 per cent of women, English was not their first language. A total of 66 languages were recorded. Sixty two per cent (1673) of all the women were between 20 and 34 years. Overall half of all the women attending did not have children. Though in some ethnic groups most women were parous, less than 20 per cent of Caribbean (born Caribbean) West African and Turkish Cypriot women and only six per cent of Turkish/Kurdish women born in Turkey had not had children. Thirty three per cent of women admitted to having had one or more terminations although there was only a 90 per cent response rate to this question. While between 20 and 25 per cent of United Kingdom, EEC and non EEC European and black British women had had one or more abortions, 49 per cent of West African, 43 per cent of Kurdish and 40 per cent of Turkish Cypriot women had had one or more abortions. The lowest percentage of women admitting to a termination were Irish (12 per cent). The majority of women did choose a method or methods of contraception. The oral contraceptive pill and the condom were the most popular methods, often being used together The method used was influenced by age and ethnicity. Younger women opted for 'the pill' while older women chose the intrauterine device. The combined pill and condom were relatively equally popular with UK, Irish, EEC European, Caribbean (born Caribbean, born UK) and 'other' groups of women; while the intrauterine device was the favoured method of Kurdish/Turkish women born in Turkey. Depo-Provera was used principally by UK, European, Caribbean (born Caribbean, born UK) and African (West and East) women. Twelve per cent of women were recorded as not using a method. These women might have attended for a pregnancy test, cervical smear, advice about general health, gynaecological problems, though this was not specifically recorded. These women featured in all age groups. While a third were UK European, two thirds were of other ethnic groups. This would appear to illustrate that those women do seem to be aware that family planning clinics can provide services in addition to supplying contraceptive methods. It was noted that the Kurdish/Turkish women favoured one particular clinic sited in the ante natal department of the local hospital (the North Middlesex) where linkworkers are available. They accounted for 34 per cent of those who attended (128 out of 371). However at all but one of the clinic sites, which are spread around the borough, the UK European group was in a minority ranging from 20 to 47 per cent in attendance, compared to other ethnic groups. It is proposed that ethnic monitoring will be routinely recorded from April 1998 for new and first time attenders. It is also planned to work more closely with various ethnic minority groups in the community.

Abortion, Induced↗
PubMed2000

Inequality of child mortality among ethnic groups in sub-Saharan Africa.

Accounts by journalists of wars in several countries of sub-Saharan Africa in the 1990s have raised concern that ethnic cleavages and overlapping religious and racial affiliations may widen the inequalities in health and survival among ethnic groups throughout the region, particularly among children. Paradoxically, there has been no systematic examination of ethnic inequality in child survival chances across countries in the region. This paper uses survey data collected in the 1990s in 11 countries (Central African Republic, Côte d'Ivoire, Ghana, Kenya, Mali, Namibia, Niger, Rwanda, Senegal, Uganda, and Zambia) to examine whether ethnic inequality in child mortality has been present and spreading in sub-Saharan Africa since the 1980s. The focus was on one or two groups in each country which may have experienced distinct child health and survival chances, compared to the rest of the national population, as a result of their geographical location. The factors examined to explain potential child survival inequalities among ethnic groups included residence in the largest city, household economic conditions, educational attainment and nutritional status of the mothers, use of modern maternal and child health services including immunization, and patterns of fertility and migration. The results show remarkable consistency. In all 11 countries there were significant differentials between ethnic groups in the odds of dying during infancy or before the age of 5 years. Multivariate analysis shows that ethnic child mortality differences are closely linked with economic inequality in many countries, and perhaps with differential use of child health services in countries of the Sahel region. Strong and consistent results in this study support placing the notion of ethnicity at the forefront of theories and analyses of child mortality in Africa which incorporate social, and not purely epidemiological, considerations. Moreover, the typical advantage of relatively small, clearly defined ethnic groups, as compared to the majority in the national population, according to fundamental indicators of wellbeing--child survival, education, housing, and so forth--suggests that many countries in sub-Saharan Africa, despite their widespread poverty, are as marked by social inequality as are countries in other regions in the world.

Africa South of the Sahara↗
PubMed2000

Evaluating the impact of tuberculosis control: number of deaths prevented by short-course chemotherapy in China.

BACKGROUND: Tuberculosis (TB) is still amongst the most important causes of human morbidity and mortality, killing approximately two million people each year. Standard short-course chemotherapy (SSCC) can rapidly control illness and dramatically reduce the chance of death, but the impact of treatment has rarely been evaluated in these terms. METHOD: We developed a mathematical model that makes use of routinely-collected data to calculate the number of deaths directly prevented by TB treatment (i.e. excluding those due to reduced transmission). The method was applied to the world's largest TB control programme covering over 500 million people in 12 provinces of China. RESULTS: Counties which had been enrolled in the programme since 1991 were, by 1997, preventing at least 46% (37-56%) of the TB deaths that would otherwise have occurred. If replicated across the entire TB control programme area, this would amount to 30 000 (range 26 000-59 000) deaths directly prevented each year. CONCLUSIONS: Short-course chemotherapy has substantially reduced TB mortality in half of China. The analytical method described here could be applied to TB control operations in many other countries, and should help to quantify the true burden of tuberculosis alleviated by SSCC.

Anti-Bacterial Agents↗
PubMed2000

[Use of the ACSL simulation language for physiologic toxicokinetic models].

For the description of the processes of absorption, excretion or elimination of chemicals, the open one- or two-compartment models have been used thus far. The latter consist mainly of the fast (central) and slow (peripheral) compartments. The toxicological studies were based on an assumption that the organic processes develop according to is the first order kinetic reaction. However, the absorption, elimination or excretion of toxic chemicals are in fact much more complicated processes that should be explained using, e.g. the physiologically-based toxicokinetic (PBTK) models, covering physiological, biochemical and metabolic parameters, as well as the allometric calibration of selected parameters for interspecies extrapolations, and in vitro/in vivo extrapolations of metabolic parameters. Simulation languages, e.g. ACSL (Advanced Continuous Simulation Language) are indispensable application tools to be operated with PBTK models. They have been developed for modelling systems described by time-dependent non-linear differential equations and/or transfer functions. ACSL with its interfaces (ACSL Builder, ACSL Graphic Modeller, ACSL Math) ensures data input and communication inside the model by the control, transfer and computed parameters. The physiologically-based toxicokinetic models employ a large number of different parameters, which enables, e.g. forecasting the dose/effect or dose/response relationship absorption rate, metabolic pathways, excretion or elimination according to the absorbed dose of xenobiotic; evaluation of risk assessment; extrapolation from high to low doses characteristic of environmental exposure or setting biological exposure limits.

Body Fluid Compartments↗
PubMed2001

Estimation of wall shear stress in bypass grafts with computational fluid dynamics method.

Coronary artery bypass graft (CABG) operation for coronary artery disease with different types of grafts has a large clinical application world wide. Immediately after this operation patients are usually relieved of their chest pain and have improved cardiac function. However, after a while, these bypass grafts may fail due to for example, neointimal hyperplasia or thrombosis. One of the causes for this bypass graft failure is assumed to be the blood flow with low wall shear stress. The aim of this research is to estimate the wall shear stress in a graft and thus to locate areas were wall shear stress is low. This was done with the help of a blood flow computer model. Post-operative biplane angiograms of the graft were recorded, and from these the three-dimensional geometry of the graft was reconstructed and imported into the computational fluid dynamics (CFD) program FLUENT. The stationary diastolic flow through the grafts was calculated, and the wall shear stress distribution was estimated. This procedure was carried out for one native vessel and two different types of bypass grafts. One bypass graft was a saphenous vein and the other one was a varicose saphenous vein encased in a fine, flexible metal mesh. The mesh was attached to give the graft a defined diameter. The computational results show that each graft has distinct areas of low wall shear stress. The graft with the metal mesh has an area of low wall shear stress (< 1 Pa, stationary flow), which is four times smaller than the respective areas in the other graft and in the native vessel. This is thought to be caused by the smaller and more uniform diameter of the metal mesh-reinforced graft.

Computer Simulation↗