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61.
The occurrence of complications during pregnancy depends less on the degree of human development than differences in the way complications in pregnancy are detected and managed. It is the quick diagnosis and correct management that really contribute to the enormous differences in maternal mortality ratios between countries and regions. Understanding of the determinants of maternal mortality may be improved by studying cases of severe maternal morbidity. In this paper, various approaches to the concept of severe maternal morbidity and near-misses are discussed, and the relationship between these and maternal deaths. Although no consensus has been reached on a strict definition of near-miss or severe maternal morbidity, we show that the definitions used may be tailored to support diverse objectives, including monitoring progress, epidemiological surveillance and auditing of health care. We conclude that the versatility of the concept, the greater frequency of cases available for study and the possibility of interviewing the survivors of severe complications all support the value of studying severe maternal morbidity to help guide local efforts to reduce maternal mortality. Although this may almost be a reality in developed countries, it continues to represent an important and difficult challenge to overcome in places where its benefits would be most evident.  相似文献   
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Acute otomastoiditis and its complications: role of CT   总被引:2,自引:0,他引:2  
Acute bacterial (suppurative) otomastoiditis responds to antibiotic treatment; radiologic study is required only when there is clinical suggestion of coalescent mastoiditis, intracranial complications, or an underlying chronic disease. Computed tomography (CT) is the method of choice for evaluating otogenic intra- or extra-cranial complications. CT scans can show stages of disease progression when infection has spread by way of soft tissue, blood, and bone pathways into the dural venous sinuses, meninges, labyrinth, facial nerves, epidural and other intracranial spaces. When there is clinical suggestion of acute coalescent mastoiditis, a CT scan of the temporal bone can confirm the presence of rarefying osteitis, coalescence of the air cells, and subperiosteal abscess.  相似文献   
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HIV-1 M originated from SIVcpz endemic in chimpanzees from southeast Cameroon or neighboring areas, and it started to spread in the early 20th century. Here we examine the factors that may have contributed to simian-to-human transmission, local transmission between humans, and export to a city. The region had intense ape hunting, social disruption, commercial sex work, STDs, and traffic to/from Kinshasa in the period 1899–1923. Injection treatments increased sharply around 1930; however, their frequency among local patients was far lower than among modern groups experiencing parenteral HIV-1 outbreaks. Recent molecular datings of HIV-1 M fit better the period of maximal resource exploitation and trade links than the period of high injection intensity. We conclude that although local parenteral outbreaks might have occurred, these are unlikely to have caused massive transmission. World War I led to additional, and hitherto unrecognized, risks of HIV-1 emergence. We propose an Enhanced Heterosexual Transmission Hypothesis for the origin of HIV-1 M, featuring at the time and place of its origin a coincidence of favorable co-factors (ape hunting, social disruption, STDs, and mobility) for both cross-species transmission and heterosexual spread. Our hypothesis does not exclude a role for parenteral transmission in the initial viral adaptation.  相似文献   
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Poecilia reticulata were exposed to herbicide Roundup Transorb® for micronucleus test, nuclear abnormalities and comet assay. The exposure-concentrations were based on CL50–96 h following 0, 1.41, 2.83, 4.24 and 5.65 μL L?1 for 24 h. Micronucleus and comets were significantly increased in the gill erythrocyte cells after herbicide exposure compared with the non-exposed group. Results showed a gradual increase in the number of damaged cells, indicating a concentration-dependent effect and that this herbicide was mutagenic and genotoxic to P. reticulata and this effect could be attributed to a combination of compounds contained in the formulation with the active ingredient glyphosate.  相似文献   
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Our aim is to model the frequency of certain behavioral acts, especially those that are likely to transmit communicable diseases between persons. We develop a generalized linear model on the basis of the beta prime distribution to model the responses to a survey question of the form, ‘When was the last time that you engaged in this behavior?’ Intuitively, individuals reporting more recent events are more likely to have greater frequency of the risky behavior. The beta prime distribution is especially suited to this application because of its long tail. We adjust for length‐biased sampling. We show how to use this distribution as the basis of a linear regression model that accounts for differences in demographic and psychological characteristics of the respondents. We discuss estimation of parameters, residuals, tests for heterogeneity of these parameters, and jackknife measures of influence. We apply the methods to a survey of alcohol abuse use among individuals who are at high risk for spreading HIV and other communicable diseases in a study conducted in Saint Petersburg, Russia. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
70.
ObjectivePoor oral status, represented by partial/complete tooth loss, may lead to changes in food choice, which may ultimately lead to underweight, overweight, or obesity. The aim of this study is to evaluate whether poor oral status is associated with underweight or overweight/obesity, regardless of physical activity.MethodsThis cross-sectional study is part of a major project, The Frailty in Brazilian Elderly Study, carried out in Campinas, Brazil (2008–2009). The sample was composed of 900 independent-living older adults. Complete data were available for 875 individuals including sociodemographic, self-reported amount of medications used and eating difficulty questionnaire, smoking habit, depressive symptoms, physical activity, oral examination, and anthropometric assessments according to the WHO criteria. Body mass index was used as an outcome. Multinomial logistic regression was adjusted for confounding variables.ResultsThe mean age of the sample was 72.7 y (±5.81) and the prevalence of edentulism was 47.7%. Edentate individuals not wearing dentures were more likely to be underweight [odds ratio (OR) = 3.94, 95% confidence interval (CI) 1.14–13.64] and overweight/obese (OR = 2.88, 95%CI 1.12–7.40). Males (OR = 0.56, 95%CI 0.36–0.85) and those not using medications (OR = 0.41 95%CI 0.24–0.70) were less likely to be overweight/obese. Individuals who smoke (OR = 2.62, 95%CI 1.26–5.44) were more likely to be underweight. Older individuals with family income between 3.1 and 5 minimum wage (OR = 1.69, 95%CI 1.00–2.87) were more likely to be overweight/obese.ConclusionTo our knowledge, this is one of the first studies associating poor oral health, represented by edentulism not rehabilitated with dentures, with unfavorable body mass, regardless of the two major confounders, physical activity and depression symptoms.  相似文献   
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