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For the first time the quantitative microbiological characteristics of diarrheas caused by enterotoxigenic E. coli (ETEC), serovars O15: H?, O34: H10, O78: H? O148: H? and O148: H28, in 5 patients are presented. The multiplication of ETEC in the patients' body has provided clinical material permitting the authors to reveal, for the first time, the capacity of ETEC for the colonization of the intestine and to judge of their etiological role in the diseases. A close relationship between the clinical manifestations of the disease and the number of ETEC per g of feces in its dynamics has been established. These data indicate that patients may be regarded as the possible sources of infection.  相似文献   

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ABSTRACT: One of the most commonly used stress biomarkers is cortisol, a glucocorticoid hormone released by the adrenal glands that is central to the physiological stress response. Free cortisol can be measured in saliva and has been the biomarker of choice in stress studies measuring the function of the hypothalamic-pituitary-adrenal axis. Chronic psychosocial stress can lead to dysregulation of hypothalamic-pituitary-adrenal axis function and result in an abnormal diurnal cortisol profile. Little is known about objectively measured stress and health in Latino populations in the United States, yet this is likely an important factor in understanding health disparities that exist between Latinos and whites. The present study was designed to measure cortisol profiles among Latino immigrant farmworkers in Oregon (USA), and to compare quantitative and qualitative measures of stress in this population. Our results indicate that there were no sex differences in average cortisol AUCg (area under the curve with respect to the ground) over two days (AvgAUCg; males = 1.38, females = 1.60; p = 0.415). AUCg1 (Day 1 AUCg) and AvgAUCg were significantly negatively associated with age in men (p < 0.05). AUCg1 was negatively associated with weight (p < 0.05), waist circumference (p < 0.01) and waist-to-stature ratio (p < 0.05) in women, which is opposite to the expected relationship between cortisol and waist-to-stature ratio, possibly indicating hypothalamic-pituitary-adrenal axis dysregulation. Among men, more time in the United States and immigration to the United States at older ages predicted greater AvgAUCg. Among women, higher lifestyle incongruity was significantly related to greater AvgAUCg. Although preliminary, these results suggest that chronic psychosocial stress plays an important role in health risk in this population. (271 words).  相似文献   

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The way of improving degraded soils fertility and particularly of improving its microbial activity is to add “young” exogenous organic matter that contribute to provide labile organic matter to stimulate the life of the microorganisms existing in the soil. This organic matter will also improve both the retention and hydraulic characteristics of the degraded soils, all this contributing to soil restoration. In this study, the microbiological, biochemical, soil-physical and hydrological effects of the addition of a municipal solid waste compost to a degraded soil in El Campello, SE Spain were evaluated in a field experiment. Soil samples from experimental plots were analyzed 6 and 18 months after soil amendment. In both sampling time treated plots showed significantly higher microbial biomass carbon and dehydrogenase activity values than control, indicating that soil microbial population’s development and activity were stimulated by compost addition, this effect being not ephemeral but lasting in the time. Soil urease activity was not affected by compost addition while protease hydrolysing N-α-benzoil-L-argininamide (BAA) activity was strongly stimulated by the incorporation of compost into the soils. Phosphatase and β-glucosidase activities were also stimulated by the organic amendment, this stimulation being particularly noticeable 18 months after the compost addition. Nevertheless, this increase in soil microbial populations and activity did not result in an increase in soil aggregation and hydrological parameters. This can be due to the high content of carbonates and Ca2+ ions in these calcareous soils, that lead to an initially high content of water-stable macroaggregates. Presented at the International Conference on Bioclimatology and Natural Hazards, Poľana nad Detvou, Slovakia, 17–20 September 2007.  相似文献   

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Using the 2003 New Immigrant Survey data, we explore marital behaviour among new immigrants in the USA. Marital assimilation with mainstream US natives was highest among European immigrants, followed by Latin Americans, Southeast Asians, East Asians, and finally South Asians. There is no single ‘Asian’ pattern of marital assimilation. While South Asians and East Asians defy the classical assimilation theory with their strong resistance to intermarriage within the mainstream despite their high degree of structural assimilation, Southeast Asians display high rates of such marital assimilation. Europeans, as predicted by classical theory, evince high rate of marital assimilation. Latin Americans and Southeast Asians lie in between the two extremes of Europeans and other Asian subgroups. While they seem to follow a path of segmented assimilation by demonstrating within-region endogamy, compared to Europeans they have only a slightly higher propensity to marry within their nationality, suggesting ongoing assimilation along classical lines.  相似文献   

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Two hundred and six Asian, 99 African, 99 Chinese, and 102 Scottish children from 172 families were studied to ascertain infant-feeding practices. After arriving in the United Kingdom most of the immigrant mothers had not wished to breast-feed their babies because of wrong information or misconceptions about British infant-feeding practices. The Asians had largely adopted British habits of introducing solid foods to their babies'' diets, but the habits of the African and Chinese mothers in this respect had changed little. Furthermore, many of the African and Chinese children had received no vitamin preparation. The survey showed that all mothers resident in Britain urgently need advice on some aspects of infant feeding.  相似文献   

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Cote J  Clobert J 《Ecology letters》2007,10(5):411-417
‘Should I stay or should I go?’ is a fundamental question facing any candidate for emigration, as emigrating without outside information has major costs. Most studies on this topic have concentrated on risk‐reducing strategies (e.g. exploration) developed after leaving the natal habitat. The idea that information might be acquired before leaving has not been investigated. Immigrants carrying information about their origins could provide such information to potential emigrants in their initial habitat. We manipulated the density of common lizard (Lacerta vivipara) populations, to investigate whether immigrants originating from these populations transmitted such information to the population they joined. Emigration of the residents of this new population clearly depended on the origin of the immigrant. Immigrants are therefore a source of information, in this case about surrounding population densities, and may have a major effect on dispersal and species persistence in a fragmented habitat.  相似文献   

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Observations during 1971 and 1972 of some of the physical, chemical, and microbiological characteristics of contrasting Anglesey beaches, Newborough and Llanddona, are reported. The fine sandy beach at Newborough was observed to be very unstable and topographical changes were recorded. In particular, the movement of a sand wave across the intertidal zone from low water to extinction at the foot of the dune system was observed. The more extensive fine sandy beach at Llanddona had greater stability.Chemically, each beach was variable both spatially and temporally, with ill-defined patterns of concentration changes. Sand from Newborough beach was low in organic carbon (0.07–0.40 mg C/g dry sand) and well aerated, and the soluble inorganic nitrogen in the ground water (up to 30 μg-at. N/l) was dominated by nitrate form (up to 22 μg NO3-N/l). By contrast, Llanddona sand had a more variable organic carbon content (0.22–2.25 mg C/g dry sand), was wetter, and poorly aerated with consequent sulphide lenses; its dissolved inorganic nitrogen (over 70 μg-at. N/l) was completely dominated by the ammonium form.Microbiologically, the beaches possessed dissimilar bacterial floras, and sediment from Llanddona gave higher bacterial counts than that from Newborough. For both beaches it is shown that estimated bacterial numbers decreased with depth as well as down the intertidal zone.  相似文献   

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This article compares ethnic and sub-ethnic attachments in Chinese, Indian, and Korean immigrants in New York City, based on results of a survey. Indian respondents, with much higher levels of education and fluency in English, show a lower level of cultural ethnic attachment than the other two groups. The Chinese show the lowest level of formal ethnic affiliation, mainly due to their much lower level of religious affiliation. All three groups show extremely high levels of informal ethnic networks. However, Chinese and Indian respondents largely limit their close friendships to their sub-ethnic group, based on national origin, religion, regional origin and/or language, while Korean respondents, characterized by group homogeneity, tend to maintain close friendships with all other Koreans. Much larger proportions of Chinese and Indian respondents than Koreans choose the sub-ethnic identity label and they show much lower levels of loyalty to their homeland than Korean respondents.  相似文献   

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This study of immigrants’ integration in Israel centers on one major subjective parameter, namely the immigrant's identity. To explain it we explore a series of possible factors: demographic variables, economic status, and human and social capital characteristics. Three recent immigrant groups are examined: from Western countries, from the former Soviet Union (FSU), and from Ethiopia. These immigrants came to Israel during the last two decades from different societies, following different immigration circumstances and various motives.

The findings, based on the 2007 Ruppin survey data, point to the significant impact of the identity as perceived by veteran Israelis on the immigrants’ self-identity for the three groups under study. Also, different variables affect each of the immigrant groups. FSU immigrants behaved according to most of our hypotheses, whereas Western and Ethiopian immigrants did not. Findings are discussed in light of the debate on measuring and defining immigrants’ identity.  相似文献   

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Among immigrants resident in greater London from Europe, Ireland, the USSR, the old Commonwealth countries of Australia, Canada, and New Zealand, North and South America, Egypt, Turkey, and Iran the incidence of admission to hospital for probable multiple sclerosis (MS) between 1960 and 1972 was high or moderately high. The incidence was the same order as that found in those born in the United Kingdom. Immigrants from India, Pakistan, and other Asian countries and from new Commonwealth Africa and America, which includes the West Indies, had a low incidence of hospital admission for MS. Immigrants from countries where the risk of MS is low whose parents were born in Europe had a reduced incidence of admission to hospital but not the very low incidence found in those parents were also born in these countries. Emigrating to England from low risk parts of the world did not seem to increase the risk of developing MS.  相似文献   

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王雪芹  张奇春  姚槐应 《生态学报》2012,32(5):1412-1418
研究了典型毛竹林毛竹高速生长期间土壤碳氮动态及其微生物生态特性。结果表明:毛竹高速生长期间,3个试验地土壤全氮、碱解氮、铵态氮、硝态氮及总有机碳和水溶性有机碳(DOC)的含量均有不同幅度的下降,其中25℃蒸馏水提取DOC(25℃DOC)降幅分别达到51%、22%和223%,且25℃DOC下降幅度明显大于80℃DOC的下降幅度。随毛竹生长,土壤全氮和有机碳含量变化较为明显,相关分析表明两者呈极显著的正相关(R2=0.89**)。同时,土壤微生物量碳含量大幅度降低,由原来的800 mg/kg降到了525 mg/kg。采用PLFA法对土壤微生物群落结构进行了分析,代表细菌的饱和脂肪酸(14:0,16:0,18:0,20:0,i15:0,i16:0,i17:0,i18:0,a15:0,a17:0)基本上都分布在载荷图的右侧;代表真菌的不饱和脂肪酸(18:2w6,9c/18:0ANTE)分布在主成分载荷图的左侧,表明随着毛竹生长,土壤中细菌含量减少,真菌含量增加。说明毛竹的高速生长消耗了土壤中的碳氮,同时对土壤微生物群落结构产生了明显的影响。  相似文献   

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The efficiency of tuberculosis control programs is largely determined by methods for rapid diagnosis of the agent. In comparison with the traditional methods, new molecular technologies for characterization of mycobacteria appear to be more promising, because the result can be obtained in almost no time. Sixty-five strains of M. tuberculosis isolated in various regions of Russia were investigated. Drug resistance and strain appurtenance of this sample were determined by classical (absolute concentrations method, IS6110-RFLP) and modern molecular genetic methods (detection of mutations in rpo B gene, DRE-PCR). The spectrum of mutations of the rpoB gene associated with rifampicin resistance was evaluated by direct sequencing. Mutations involving codons 531 (62.7%), 526 (18.6%), and 516 (10.2%) of rpoB gene predominated in the studied sample. The studied strains were discriminated into 52 individual strains by IS6110-RFLP and DRE-PCR typing. Analysis of the resultant genetic variants showed the predominance of M. tuberculosis family W. The efficiency of combined approach to screening for M. tuberculosis is discussed.  相似文献   

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Abstract

Research has shown that individuals in Sweden with foreign-sounding surnames who take on more Swedish-sounding or neutral surnames have a positive earnings progression compared to individuals who keep their foreign-sounding names. This article explores the strategies underlying these surname changes. I draw on forty-five interviews from a population of individuals with Middle Eastern backgrounds who changed surnames during the 1990s. Drawing on stigma and destigmatization theory, I argue that immigrant name change, a strategy typically associated with cultural assimilation, is a destigmatization strategy aiming for pragmatic assimilation. Through passing (as either Swedish or non-Middle Eastern), immigrants may keep the benefits of maintaining ethnic identity in their private life and the benefits of more easy public interactions outside the ethnic group. This study also illustrates how the institutional enabling of name change both creates and enables pragmatic assimilation.  相似文献   

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Background:

Evidence suggests that migrant groups have an increased risk of psychotic disorders and that the level of risk varies by country of origin and host country. Canadian evidence is lacking on the incidence of psychotic disorders among migrants. We sought to examine the incidence of schizophrenia and schizoaffective disorders in first-generation immigrants and refugees in the province of Ontario, relative to the general population.

Methods:

We constructed a retrospective cohort that included people aged 14–40 years residing in Ontario as of Apr. 1, 1999. Population-based administrative data from physician billings and hospital admissions were linked to data from Citizenship and Immigration Canada. We used Poisson regression models to calculate age- and sex-adjusted incidence rate ratios (IRRs) and 95% confidence intervals (CIs) for immigrant and refugee groups over a 10-year period.

Results:

In our cohort (n = 4 284 694), we found higher rates of psychotic disorders among immigrants from the Caribbean and Bermuda (IRR 1.60, 95% CI 1.29–1.98). Lower rates were found among immigrants from northern Europe (IRR 0.50, 95% CI 0.28–0.91), southern Europe (IRR 0.60, 95% CI 0.41–0.90) and East Asia (IRR 0.56, 95% CI 0.41–0.78). Refugee status was an independent predictor of risk among all migrants (IRR 1.27, 95% CI 1.04–1.56), and higher rates were found specifically for refugees from East Africa (IRR 1.95, 95% CI 1.44–2.65) and South Asia (IRR 1.51, 95% CI 1.08–2.12).

Interpretation:

The differential pattern of risk across ethnic subgroups in Ontario suggests that psychosocial and cultural factors associated with migration may contribute to the risk of psychotic disorders. Some groups may be more at risk, whereas others are protected.Meta-analytic reviews suggest that international migrants have a two- to threefold increased risk of psychosis compared with the host population, and the level of risk varies by country of origin and host country.1,2 This increased risk may persist into the second and third generations.2,3 Incidence rates are not typically found to be elevated in the country of origin;47 therefore, it is believed that the migratory or postmigration experience may play a role in the etiology.The migration-related emergence of psychotic disorders is a potential concern in Canada, which receives about 250 000 new immigrants and refugees each year.8 However, there is a notable lack of current epidemiological information on the incidence of psychosis among these groups.9 Hospital admission data from the early 1900s suggest that European migrants to British Columbia had a higher incidence of schizophrenia than the general population,10 and more recent data from Ontario suggest higher rates of hospital admission for psychotic disorders in areas with a large proportion of first-generation migrants.11 The fact that a large and increasing proportion of Canada’s population are migrants has been cited as a potential explanation for the higher prevalence of schizophrenia compared with international estimates.12The province of Ontario is home to the largest number of migrants in Canada, with first-generation migrants constituting nearly 30% of the population. Canada operates on a human capital model of immigration, using a points-based system that favours younger age, higher education, and proficiency in English or French. Nearly 60% of all newcomers to Canada are economic migrants, 27% are sponsored by a relative living in Canada, and 13% are refugees or temporary workers.8 Canada also requires a prearrival medical examination, but less than 0.001% of all applications are denied on the basis of medical grounds, and exemptions may be granted for refugees and some family-reunification applicants.13The Canadian migration process differs from that of many countries where the association between migration and psychotic disorders has been previously investigated.1,2 In most of these countries, migrants generally originate from a smaller number of countries that have historic ties to the host country, and there tends to be a low proportion of refugees, although these processes have changed in recent years. In Canada, migrants come from a wide array of countries, admission policies focus on migrants with professional skills and there is a larger proportion of refugees. Few studies to date have examined the role of refugee status in the risk of psychotic disorders14 or have assessed all of the migrant groups within a country, because most studies focus on particular groups considered to be at high risk.1 An examination of migrants to Canada offers a unique opportunity to investigate the risk of psychotic disorders in a group with diverse geographical origins, and the larger proportion of refugees also allows us to investigate their risk separately from immigrant groups. Thus, the breadth, scope and scale of migration to Canada over time offers a diverse and deep population for advancing our understanding of why some groups may have a higher risk of psychotic disorders.Our primary objective was to examine the incidence of schizophrenia and schizoaffective disorders over a 10-year period in first-generation immigrants and refugees in Ontario, relative to the general population. We also compared the incidence among specific migrant groups, stratified by country of birth and refugee status, because research suggests differences in the degree and direction of risk.1,2 We restricted the sample to first-generation migrants to estimate the extent to which sociodemographic factors had an impact on the risk of schizophrenia and schizoaffective disorders among all migrants.  相似文献   

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