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991.
992.
This paper discusses the negative externalities associated with the intensive use of pesticides in the Brazilian savannah. These externalities are mainly related to impacts on the environment and on human health (rural workers and families, consumers), the costs of which end up being socialized. The externality considered in the present paper is of soil and water contamination by pesticides. The data source is the questionnaire of the Basic Municipal Information Research applied in 2003. Maps are used in order to associate contaminated areas with agricultural activity. Some risk factors associated with soil and water contamination by pesticides such as seasonal crop area, air pollution by burning and weed proliferation, were obtained through a logistic regression. The study concludes that the results can be helpful to formulate policies and aid in the design of regulating instruments and the definition of priority areas where preventive actions should be implemented.  相似文献   
993.
994.
In the early 1990s, a group of British researchers developed a new methodology for healthcare resource allocation based on need. The methodology's main characteristics are to draw on the theoretical model for healthcare services demand and apply data on health services utilization to estimate needs-based use. The objective of the current study was to assess the applicability of this methodology for allocating Federal resources at the local level in Brazil. Data from all acute hospital admissions in 1999 came from the Inpatient Information System of the Unified National Health System (SUS). The country was divided into 134 geographic areas. The statistical models tested to estimate needs-based use applied the following need variables: infant mortality rate; standardized mortality rate; illiteracy rate; proportion of households headed by women; and mean number of household members. All tested models showed negative regression coefficients, indicating that the methodology is inadequate for resource allocation based on need in places like Brazil with large social inequalities in healthcare utilization.  相似文献   
995.
996.
The most common form of non-syndromic autosomal recessive deafness (NSRD) is caused by mutations in the GJB2 gene. Recently, a deletion truncating the GJB6 gene, called del(GJB6-D13S1,830) has also been described normally accompanying mutations in another allele of the GJB2 gene. Among all the mutations described to date, 35delG in the GJB2 gene is the most common. Preliminary data suggest that pathologic changes due to GJB2 mutations do not affect the spiral ganglion cells, which are the site of stimulation of the cochlear implant. Besides, the survival of the spiral ganglion cells is believed to be an important determinant of the outcome after surgery. Therefore, we have studied 49 non-syndromic deaf patients with unknown etiologies in order to determine the prevalence of GJB2 and GJB6 gene mutations in patients undergoing cochlear implantation surgery. Also, the molecular studies were performed using polymerase chain reaction amplification and direct sequencing. As a result, we found 19 individuals with GJB2 mutation including one new mutation (K168R), one patient homozygous for the del(GJB6-D13S1,830). These results establish that genetic screening can provide an etiologic diagnosis, and may help with prognosis after cochlear implantation, as has been hypothesized in previous studies.  相似文献   
997.

Purpose

Central line-associated bloodstream infection (CLABSI) is an important cause of complications in paediatric intensive care units (PICUs). Peripherally inserted central catheters (PICCs) could be an alternative to central venous catheters (CVCs) and the effect of PICCs compared with CVCs on CLABSI prevention is unknown in PICUs. Therefore, we aimed to evaluate whether PICCs were associated with a protective effect for CLABSI when compared to CVCs in critically ill children.

Methods

We have carried out a retrospective multicentre study in four PICUs in São Paulo, Brazil. We included patients aged 0–14 years, who needed a CVC or PICC during a PICU stay from January 2013 to December 2015. Our primary endpoint was CLABSI up to 30 days after catheter placement. We defined CLABSI based on the Center for Disease Control and Prevention’s National Healthcare Safety Networks (NHSN) 2015 surveillance definitions. To account for potential confounders, we used propensity scores with inverse probability weighting.

Results

A total of 1660 devices (922 PICCs and 738 CVCs) in 1255 children were included. The overall CLABSI incidence was 2.28 (95% CI 1.70–3.07)/1000 catheter-days. After covariate adjustment using propensity scores, CVCs were associated with higher risk of CLABSI (adjHR 2.20, 95% CI 1.05–4.61; p = 0.037) compared with PICCs. In a sensitivity analysis, CVCs remained associated with higher risk of CLABSI (adjHR 2.18, 95% CI 1.02–4.64; p = 0.044) after adding place of insertion and use of parenteral nutrition to the model as a time-dependent variable.

Conclusions

PICC should be an alternative to CVC in the paediatric intensive care setting for CLABSI prevention.
  相似文献   
998.
Summary  We report imaging abnormalities from 5 brain MR examinations in 4 children with methylmalonic acidaemia between the ages of 20 days and 31 months. In addition to bilateral basal ganglia lesions (pallidum) observed in 3 of 4 children, we found signs of delayed brain maturation (myelination delay, immature gyral pattern, incomplete opercularization) in all children and signs of a white matter disorder in the 3 older children. Unexpectedly, brainstem and cerebellar changes were present in all children. Reviewing the brain imaging changes reported for methylmalonic acidaemia, we discuss the findings and patterns observed in our patients. We postulate that delayed myelination and signs of a white matter disorder as well as brainstem and cerebellar involvement are common findings and may be due to a chronic neurotoxic effect on the developing and ageing brain. Competing interests: None declared References to electronic databases: mut and mut0 defects of methylmalonyl-CoA mutase: OMIM #251000. Defective synthesis of adenosylcobalamin cblA type: OMIM #251100. Defective synthesis of adenosylcobalamin cblB type: OMIM #251110. Methylmalonyl-CoA mutase: EC 5.4.99.2.  相似文献   
999.
We report on a case of an unexpected dissection of the left main stem during percutaneous coronary intervention complicated by involvement of the ascending aorta with pericardial tamponade. After pericardial drainage, haemodynamic stabilization, and extensive stenting of the propagating dissection, safe discharge was possible without surgical intervention.  相似文献   
1000.
Hereditary hemochromatosis (HH) is classically associated with a Cys282Tyr (C282Y) mutation of the HFE gene. Non-C282Y HH is a heterogeneous group accounting for 15% of HH in Northern Europe. Pathogenic mutations of the transferrin receptor 2 (TfR2) gene have been identified in 4 Italian pedigrees with the latter syndrome. The goal of this study was to perform a mutational analysis of the TfR2 and HFE genes in a cohort of non-C282Y iron overload patients of mixed ethnic backgrounds. Several sequence variants were identified within the TfR2 gene, including a homozygous missense change in exon 17, c2069 A-->C, which changes a glutamine to a proline residue at position 690. This putative mutation was found in a severely affected Portuguese man and 2 family members with the same genotype. In summary, pathologic TfR2 mutations are present outside of Italy, accounting for a small proportion of non-C282Y HH.  相似文献   
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