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At least 19 recordsLinked to original sources
PubMed1999

The relationship between normal erythrocyte sedimentation rate of Chinese young people and geographical factors.

In order to provide a scientific basis for the layout of a unified standard of the reference value of Chinese young people's erythrocyte sedimentation rate (ESR), the relationship between the reference values of the Chinese healthy young's ESR and five geographical factors was tested according to the Wintrobe methods. The altitude was found to be the most important factor affecting the reference value of the Chinese young's ESR. The altitude increase correlates with the decrease of the reference value of the young's ESR. The method of stepwise regression analysis was used to deduce two multivariate regression equations. If the geographical index values of a particular area of China are known, the reference value of the young's ESR of this region can be calculated by means of the regression equations. Furthermore, the depending on geographical factors, China can be divided into six districts: Qingzang, Southwest, Northwest, Southeast, North and Northeast District, according to the reference values of the Chinese young's ESR.

Adult↗
PubMedDate not supplied

Discussion on the relationship between normal hematocrit and geographical factors in China.

This paper is written in order to provide a scientific basis for laying out an unified standard of the reference value of hematocrit of Chinese healthy people. It studies the relationship between the reference values of Chinese adults' hematocrit, tested according to the Wintrobe Laws and five geographical factors. It is found that the altitude is the most important factor affecting the reference value of Chinese healthy people's hematocrit. As the altitude gradually increases, the reference value of their hematocrit also increases. By using the method of stepwise regression analysis, two multivariate regression equations are deduced. If the geographical index values in a particular area are known, the reference value of Chinese healthy people's hematocrit in this area can be established by means of the regression equations. Furthermore, according to the dependent relationship of the reference value of Chinese healthy people's hematocrit to geographical factors, China can be divided into six districts: Qingzang, Southwest, Northwest, Southeast, North and Northeast district.

Adolescent↗
PubMed1997

Geographic factors probably modulating alternative pathways in Helicobacter pylori-associated gastroduodenal pathology: a hypothesis.

It is hypothesized that probable geographic factors of nutritional type, nonrelated to development or socioeconomic level, may modulate the conversion of Helicobacter pylori-associated active chronic gastritis from its early stages to chronic atrophic gastritis (CAG). The factors could be diets low in antioxidant vitamins and other micronutrients such as selenium. In regions of the world where these modulating factors are not present, active chronic gastritis tends to stay in its early stages and to predispose individuals to duodenal ulcer. On the contrary, in regions where the modulating factors are present, the frequency of CAG increases markedly. When CAG becomes severe and extensive, hypochlorhydria ensues. Hypochlorhydria decreases the predisposition to duodenal ulcer, while CAG, a precancerous lesion, predisposes individuals to gastric cancer of the intestinal type. The hypothesis could be tested in a multicenter, multiregional study to (1) determine endoscopically and histologically the prevalence rates of duodenal ulcer, gastric ulcer, gastric cancer, and H. pylori-associated CAG in large series of dyspeptic patients and (2) correlate these prevalence rates with blood levels of micronutrients in these patients.

Disease Progression↗
PubMed1996

Hills, ridges, mountains, and roads: geographical factors and access to care in rural Kentucky.

Access to health care remains an important issue facing many individuals. Barriers to health care include financial factors, characteristics of the individuals and of the health care delivery system, as well as geographical factors. Using a telephone survey of Kentucky residents, this study investigated the relationship between the road quality and county elevation and access to health care for individuals in rural and urban areas of the state. Controlling the comparison for known individual characteristics, community characteristics, and medical infrastructure characteristics, this study uncovered that worse road conditions, measured by a road "rideability" index, were associated with longer times to reach medical care. It also found an association between higher county elevations and shorter times to reach medical care.

Catchment Area, Health↗
PubMedDate not supplied

Geographical factors and A&E attendance.

Mike Walsh demonstrates how the technique of multiple regression analysis can be used to clarify the significance of several variables in determining the geographical factors which affect A&E attendance. The results indicate that travelling distance to A&E, social status of the catchment area and the proportion of the population in the 15-29 age group are significant factors in a complex equation.

Catchment Area, Health↗
PubMed1990

[Quantitative epidemiological investigation on social, economic and geographic factors contributing to falciparum malaria in southern Henan province].

A case-control study was conducted at Xinyang prefecture, Henan province in 1988 to investigate social, economic and geographic factors believed to be associated with the occurrence of residual falciparum malaria cases. Data were obtained from 65 residual cases and 195 matched control samples from neighbours, residents in the same village and extravillage. The questionnaire contained a total of 27 relevant items. The results of analysis of conditional logistic multi-regression model with IBM PC/XT microcomputer showed that six important risk factors related to residual falciparum malaria cases, i.e., the type of breeding places, yellow-brown soil, the knowledge of malaria transmission, open-sleep habit, family's malaria history and number of livestock. The epidemiological significance of these findings was discussed briefly.

Animals↗
PubMed1992

[An epidemiological analysis on the geographic factors of esophageal cancer].

The author collects the data of esophageal cancer mortality (1971-1973) of 78 counties in Hubei Province and the data of topography, climate, soil, rock formation and geochemical elements, including 40 suspected factors. The method of linear correlation and multiple stepwise regression are used for the comprehensive analysis of relation between the geographical factors and esophageal cancer. The result is that four factors metamorphic rock, zinc, copper, chromium are suspected factors. It suggests that the four factors will need future study.

China↗
PubMedDate not supplied

Very low birth weight births at non-NICU hospitals: the role of sociodemographic, perinatal, and geographic factors.

PURPOSE: The purpose of this study was to assess the extent of variation in the percentage of very low birth weight (VLBW) infants born at perinatal Level 1 hospitals (no Neonatal Intensive Care Unit [NICU]) across California's nine geographic Perinatal regions. The role of sociodemographic, perinatal, and geographic factors was also assessed. METHODS: Multivariate analysis of California birth certificate files between 1989 and 1993, for 24,094 live-born infants weighing between 500 and 1499 gm, was conducted to identify factors associated with delivery at a Level 1 hospital. Analyses specific for race and ethnicity were also conducted for Hispanic, African American, and white cohorts. RESULTS: In the 5-year study period, 1989 through 1993, 10.5% (24,094) of all live-born VLBW infants were delivered in Level 1 hospitals. Significant variation across regions was evident, ranging from a regional low of 3.1% to a high of 24.3%. After controlling for multiple factors, the odds of delivering at a Level 1 hospital were decreased for African Americans and South East Asians and increased in Hispanic women as compared with white non-Hispanic women. For all women, less then adequate prenatal care, living in a 50% to 75% urban zip code, and living greater then 25 miles from the nearest NICU significantly increased the odds of VLBW delivery at a Level 1 hospital. For Hispanics, teen pregnancy and having two or more prior infant deaths increased the odds, whereas Medi-Cal as the payer source for delivery and two or more pregnancy complications decreased the odds of a Level 1 VLBW delivery. After taking these factors into account, when compared with Los Angeles, the odds of inappropriate delivery site ranged from 0.37 to 2.75 across California's nine geographic perinatal regions. Of this variation, 78% could be accounted for by the percentage of total births that delivered at a region's Level 1 hospitals. CONCLUSION: The overall state average of 10.5% deliveries of VLBW at Level 1 hospitals, although close to the 10% national objective for the year 2000, did not indicate the wide variation seen across California's nine geographic regions. Risk-adjusted regional differences in the likelihood of inappropriate delivery site for the high-risk VLBW infants suggest that reaching the Healthy People 2000 objective will require further strengthening of California's perinatal regional networks, especially in those regions where a high percentage of total births deliver at Level 1 hospitals.

California↗
PubMedDate not supplied

[Geographical factors in the epidemiology of intoxication with Karwinskia (tullidora) in Mexico].

Consumption of fruits from the genus Karwinskia may cause a flaccid paralysis that can be confused with the Guillan-Barré syndrome or poliomyelitis. Paralysis resulting from consumption of such fruit has emerged as a public health problem in certain regions of Mexico. The purpose of this study was to investigate geographical factors associated with this intoxication in the 72 cases reported in Mexico from 1990 to 1994. Location of cases coincides with the distribution of the 11 reported species of Karwinskia in the country. The majority of reported cases were related to the consumption of K. humboldtiana, with a smaller number involving K. mollis, K. parvifolia, K. johnstonii, and K. rzedowskii. Most cases were located in regions with dry climates (79.2%), arid vegetation (41. 7%), and altitudes under 1,000 meters above sea level (54.1%). The study establishes three different risk areas: the Balsas river region in the southwestern central part of the country; the arid northern area; and the arid and dry central area. Cases were from rural communities with low levels of schooling and poor socioeconomic conditions.

Child↗
PubMed1990

Payment to health maintenance organizations and the geographic factor.

The adjusted average per capita cost (AAPCC) payment system for Medicare risk-based plans uses a county level geographic adjustment factor to account for differences in beneficiary costs across areas. The implications of abandoning the county unit as the basis of the geographic area are examined and the merging of counties to match the geographic definition used in the prospective payment system are considered. Year-to-year variation in a county AAPCC is inversely associated with county population size and, based on year-to-year AAPCC variation, 86 percent of all counties are too small to be used for the geographic adjustment.

Aged↗
PubMed1996

Geographic factors and plasma selenium in uremia and dialysis.

The importance of selenium (Se) as an essential trace element for man has been increasingly recognized. Blood Se levels in chronic uremic patients are frequently reported to be lower than in controls. Definitive determination of the Se status in uremic patients, however, is hampered by the wide range of blood Se content in humans from different parts of the world. The present study was designed to assess and compare the Se status in two European populations from Rostock (Germany) and Chieti (Italy). Plasma Se levels were evaluated in healthy controls, chronic renal failure nondialyzed patients (CRF) and hemodialysis patients (HD). All Se determinations were performed in a single laboratory. The Se concentration was significantly higher (p < 0.005) in Italian healthy controls than in German healthy controls. In contrast, Se levels were similar in both CRF and HD patients from both cities. In both countries, the Se concentration in CRF and HD patients was significantly lower (p < 0.001) than in their corresponding controls, but no difference between CRF and HD was found. CRF and HD patients from the two countries showed quite similar laboratory and anthropometric data. In CRF patients in Chieti, a significant (p < 0.05) negative correlation between plasma Se and serum creatinine was found. In both HD groups, the length of time on HD and type of membrane dialyzer used did not influence the Se status. A significant positive correlation (p < 0.01) between Se levels and the protein catabolic rate was found in both HD groups. Uremia seems to be a strong factor which overrules the difference in Se levels that is present in healthy adults from different European countries. Uremia in itself may influence and level the Se concentration in patients with geographic diversity.

Adult↗
PubMed1986

[Effect of the geographic factor and technological regimen on thyroid hormone levels in Camborough hybrid pigs].

Qualitative analyses were carried out of the thyroid hormones (T-3, T-4, and FT-4 indices) with a total of 380 pigs of the Camborough hybrid at the age of one to four months, raised at the nucleus base of a swine-breeding complex. Analyzed was the effect of the technologic regime, the geographic location of swine-breeding complexes, and the economic purpose of the animals on the quantitative changes in the indices studied. Based on the statistical analysis the reliable intervals of the physiologic values of the T-3, T-4, and FT-4 under the conditions of the individual complexes were found to be 0.52-0.82, 0.7-1.8: 0.62-1.1, 0.61-0.99, and 0.74-1.26; 5-12, 3.6-8.9, 3.16, 2.0-10.0, and 3.8-7.7 ng/100 ml; 0.60-1.3, 0.7-1.17, 0.69-1.18, 0.73-1.03, and 0.86-1.13.

Animal Husbandry↗
PubMed1995

Occupational and geographical factors in the epidemiology of malignant mesothelioma.

In most industrialised countries mortality from malignant mesothelioma has risen steeply since about 1950 and is likely to go on doing so well into the next century. This increase, which has lagged behind the level of asbestos use by some 30 or more years, is most evident in men but less clear in women. Amphibole asbestos fibre types, crocidolite in particular, carry the greatest risk and chrysotile the least. Studies in chrysotile miners and millers, in whom the overall frequency of mesothelioma is low suggest the risk is mainly determined by the presence of contamination with amphibole fibres in the tremolite series. There is wide variation in mesothelioma incidence geographically and occupationally. Regions with the highest rates are those where crocidolite is mined; within countries, dockyard areas are most affected, probably because of amphibole use for insulation in naval ships. Occupations at high risk, apart from crocidolite miners and millers, include shipyard and insulation workers and those employed in construction trades. Data on exposure-response are scanty although occupational cohort studies suggest that risk is related to both duration and intensity of exposure. More specific confirmation of an exposure-response relationship has been obtained from lung fibre analysis in a limited number of case-referent studies.

Adult↗
PubMedDate not supplied

[The newborn infant in the Aosta Valley: preliminary statistical analysis of various ethnic and geographic factors].

We have examined 976 new-born babies in Aosta Valley retrospectively, in order to determine which risk factors were significantly linked with the high incidence of: hospitalization and infants with below average neonatal and placental weight. The new-borns of native mothers have been compared with those of immigrant mothers, and also the new-borns of parents living in mountains have been compared with those of parents living in town. Results have shown new-born babies of native mother are at a disadvantage, especially regarding: the neonatal and placental average weight and the incidence of small for gestational age infants (SGA). No statistically significant difference has been found from the geographical point of view. Our results have stimulated a desire for deeper knowledge concerning the ethnical distribution of our neonatal sample and the maternal anamnesis before delivery: these are the two problems we are presently concerning ourselves with.

Birth Weight↗
PubMed2000

Environmental and geographical factors contributing to watershed contamination with Cryptosporidium parvum oocysts.

Cryptosporidium parvum is a waterborne parasite which infects cattle and produces life-threatening zoonosis in people with impaired immune systems. Digital maps of 100-year floodplain boundaries, land use/cover, and livestock operations were used to select and characterize cattle farms in the floodplain area in Lancaster County, Pennsylvania, U.S.A. Over 21% of the cattle farms were located within 100-year floodplain boundaries. On average, a single farm comprised 12.8 ha of pasture (including buildings and farmyard) at risk of inundation. In all farms cattle had unlimited access to the creek. Manure samples collected from closed-in calf pens, cow/heifer yard runoff, and cattle paths through the creek were tested for C. parvum. On 64% of the farms (n=50) at least one sample was positive for C. parvum, and 44% of the farms had oocysts in all manure samples. Concentration varied from 90 to 371 oocysts/g and was significantly higher (P<0.02) in calf samples than in manure from cow and cow/heifer.

Animal Husbandry↗
PubMed1984

Influence of geographical factors in the distribution of pathogenic zymodemes of Entamoeba histolytica: identification of zymodeme XIV in India.

Stocks of Entamoeba histolytica isolated and maintained in a variety of culture media, both axenic and polyxenic, were compared with each other and with strains previously characterized. The present stocks were isolated from subjects living in various cities in India. Using the enzyme patterns of: E C 5319 glucose phosphate isomerase (GPI); E C 11140 L-malate: NADP+ oxidoreductase (oxaloacetate decarboxylating) (ME): E C 2751 phosphoglucomutase (PGM); and E C 2711 hexakinase (HK), developed after electrophoresis, three zymodemes were identified in 54 individual isolations of E. histolytica. Most importantly only one zymodeme associated with pathogenicity occurred, identified 28 times, among the collection, one of which was from a liver abscess.

Adult↗