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Synthetic amorphous silica (SAS) in its nanosized form is now used in food applications although the potential risks for human health have not been evaluated. In this study, genotoxicity and oxidative DNA damage of two pyrogenic (NM‐202 and 203) and two precipitated (NM‐200 and ‐201) nanosized SAS were investigated in vivo in rats following oral exposure. Male Sprague Dawley rats were exposed to 5, 10, or 20 mg/kg b.w./day for three days by gavage. DNA strand breaks and oxidative DNA damage were investigated in seven tissues (blood, bone marrow from femur, liver, spleen, kidney, duodenum, and colon) with the alkaline and the (Fpg)‐modified comet assays, respectively. Concomitantly, chromosomal damage was investigated in bone marrow and in colon with the micronucleus assay. Additionally, malondialdehyde (MDA), a lipid peroxidation marker, was measured in plasma. When required, a histopathological examination was also conducted. The results showed neither obvious DNA strand breaks nor oxidative damage with the comet assay, irrespective of the dose and the organ investigated. Similarly, no increases in chromosome damage in bone marrow or lipid peroxidation in plasma were detected. However, although the response was not dose‐dependent, a weak increase in the percentage of micronucleated cells was observed in the colon of rats treated with the two pyrogenic SAS at the lowest dose (5 mg/kg b.w./day). Additional data are required to confirm this result, considering in particular, the role of agglomeration/aggregation of SAS NMs in their uptake by intestinal cells. Environ. Mol. Mutagen. 56:218–227, 2015. © 2014 Wiley Periodicals, Inc.  相似文献   
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Objective

To discover the experiences of end-of-life patients attended by the emergency services, through the discourse of the family caregivers who accompanied the family member in this care transit.

Method

A qualitative approach study, based on the paradigm of hermeneutical phenomenology. In total, 81 family caregivers participated. The techniques used were the in-depth interview and the discussion group, with a total of 5 discussion groups and 41 interviews. The period of data collection was carried out between January 2013 and June 2014.

Results

In the network of discourses obtained with respect to “Urgent Care”, all the codes were grouped in relation to a single argumentative line: deficiencies in urgent care. Among them, we found different dimensions that are established depending on the different times of care, or the different determinant aspects of these deficiencies: disorganization of the care received, lack of experience of the professionals in emergencies, application of general protocols in the emergency services, inadequate care in the treatment received, delays in emergency care.

Conclusions

In general, we highlight the dissatisfaction of the family members with respect to the care received from the emergency services. The needs of these types of situation are not covered from these services and are of low quality. Therefore, it is necessary to reorient the care protocols for these patients.  相似文献   
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FGFR–TACC, found in different tumor types, is characterized by the fusion of a member of fibroblast grown factor receptor (FGFR) tyrosine kinase (TK) family to a member of the transforming acidic coiled-coil (TACC) proteins. Because chromosome numerical alterations, hallmarks of FGFR–TACC fusions are present in many hematological disorders and there are no data on the prevalence, we studied a series of patients with acute myeloid leukemia and myelodysplastic syndrome who presented numerical alterations using cytogenetic traditional analysis. None of the analyzed samples showed FGFR3–TACC3 gene fusion, so screening for this mutation at diagnosis is not recommended.  相似文献   
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