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Ureteric injury is one of the most serious complications of gynaecological surgery. Use of prophylactic preoperative bilateral ureteric stents to reduce ureteric injury is established in colorectal surgery and becoming commonplace in complex gynaecological surgery. The safety of the procedure has been questioned due to reports of stent-induced complications including a rare but serious phenomenon of stent-induced transient obstructive oligo-anuria termed reflex anuria, a response to manipulation and irritation of the ureters. A retrospective case-note review of patients who had bilateral ureteric stents placed prior to gynaecological surgery at Salford Royal Hospital, UK, from 2007 to 2011 was performed to identify cases of oligo-anuria post-stenting, which were not related to hypovolaemia, nephrotoxic drugs or a radiologically evident obstruction. All patients had their stents removed immediately at the end of surgery before leaving the operating theatre. Three out of 439 patients (0.7 %), who had preoperative bilateral ureteric stents, developed post-operative oligo-anuria despite relatively normal radiological assessment. In these three cases outlined below, one self-resolved, and two required urgent re-stenting to relieve obstruction. Use of ureteric stents for major gynaecological surgery can expedite intraoperative identification of the ureters to help reduce accidental ureteric injury but can directly cause complications. These three cases have contributed to knowledge of the complications of ureteric stents during major gynaecological surgery. Awareness of reflux anuria as a possible root cause of post-operative acute renal failure is important for guiding appropriate and timely management to preserve renal function.  相似文献   
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At the centre of all air quality regulation stands the right of humans to an environment that is not harmful to health and well-being. In many developing countries, including South Africa, coal-fired power station emissions are managed both from an ambient air quality and minimum emissions standpoint. Ambient air quality standards and minimum emissions standards (MES) are often in conflict with one another, as power stations in which vicinity ambient air quality standards are met still have to comply with a blanket set of MES. In developing countries this often leads to the unnecessary incurrence of already constrained financial resources. This study proposes an alternative emissions management strategy where potential human health exposure is used as a decision-making basis on which power station emissions control is founded. The potential human health exposure of population groups to primary particulate matter with a diameter of 10 μm or less (PM10), secondary sulphurous and nitrous particulate matter (PM), sulphur dioxide (SO2) and oxides of nitrogen (NOx) emissions are calculated and compared for 13 power stations in the highveld of South Africa. It was found that the potential human health exposure to individual power stations differ substantially. It is suggested that it makes more sense both from both a human health and fiscal perspective that emissions from coal-fired power stations be managed on an individual power station basis, especially in developing countries.  相似文献   
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Atrophic gastritis remains a difficult histopathological diagnosis with low interobserver agreement. The aim of our study was to compare gastritis staging and interobserver agreement between general and expert gastrointestinal (GI) pathologists using Operative Link for Gastritis Assessment (OLGA) and Operative Link on Gastric Intestinal Metaplasia (OLGIM). We enrolled 835 patients undergoing upper endoscopy in the study. Two general and two expert gastrointestinal pathologists graded biopsy specimens according to the Sydney classification, and the stage of gastritis was assessed by OLGA and OLGIM system. Using OLGA, 280 (33.4 %) patients had gastritis (stage I–IV), whereas with OLGIM this was 167 (19.9 %). OLGA stage III– IV gastritis was observed in 25 patients, whereas by OLGIM stage III–IV was found in 23 patients. Interobserver agreement between expert GI pathologists for atrophy in the antrum, incisura angularis, and corpus was moderate (kappa?=?0.53, 0.57 and 0.41, respectively, p?<?0.0001), but almost perfect for intestinal metaplasia (kappa?=?0.82, 0.80 and 0.81, respectively, p?<?0.0001). However, interobserver agreement between general pathologists was poor for atrophy, but moderate for intestinal metaplasia. OLGIM staging provided the highest interobserver agreement, but a substantial proportion of potentially high-risk individuals would be missed if only OLGIM staging is applied. Therefore, we recommend to use a combination of OLGA and OLGIM for staging of chronic gastritis.  相似文献   
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Novel biobased materials from fungal hyphae and cellulose fibers have been proposed to address the increasing demand for natural materials in personal protective equipment (PPE). Materials containing commercially available kraft fibers (KF), laboratory-made highly fibrillated hemp fibers (HF) and fungal fibers (FF) obtained from fruiting bodies of lignicolous basidiomycetes growing in nature were prepared using paper production techniques and evaluated for their mechanical and air permeability properties. SEM and microscopy revealed the network structure of materials. The tensile index of materials was in the range of 8–60 Nm/g and air permeability ranged from 32–23,990 mL/min, depending on the composition of materials. HF was the key component for strength; however, the addition of FF to compositions resulted in higher air permeability. Chemical composition analysis (Fourier-transform infrared spectroscopy) revealed the presence of natural polysaccharides, mainly cellulose and chitin, as well as the appropriate elemental distribution of components C, H and N. Biodegradation potential was proven by a 30-day-long composting in substrate, which resulted in an 8–62% drop in the C/N ratio. Conclusions were drawn about the appropriateness of fungal hyphae for use in papermaking-like technologies together with cellulose fibers. Developed materials can be considered as an alternative to synthetic melt and spun-blown materials for PPE.  相似文献   
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Rigid low-density plastic foams subjected to mechanical loads typically exhibit a nonlinear deformation stage preceding failure. At moderate strains, when the geometrical nonlinearity is negligible, such foam response is predominantly caused by the nonlinearity of deformation of their principal structural elements—foam struts. Orientational averaging of stresses in foam struts enables estimation of the stresses taken up by foams at a given applied strain. Based on a structural model of highly porous anisotropic cellular plastics filled with clay nanoplatelets and the orientational averaging, a method for calculating their nonlinear deformation is derived in terms of structural parameters of the porous material, the mechanical properties of the monolithic polymer, and filler particles and their spatial orientation. The method is applied to predicting the tensile stress-strain diagrams of organoclay-filled low-density rigid polyurethane foams, and reasonable agreement with experimental data is demonstrated.  相似文献   
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ObjectivesTo study caries prevalence/severity in 12-year-old children in Latvia and potential risk indicators.MethodsA cross-sectional oral-health national survey of 12-year-old children was conducted in 2016. A nationally representative stratified-cluster probabilistic sample of 2,138 pupils in 92 schools was selected. Children were examined by seven calibrated examiners (kappa inter-examiner, intra-examiner scores of 0.71–0.77, 0.81–0.97, respectively) at school. Enamel-non-cavitated decay (D1), enamel cavitation (D3), dentine cavitation (D5), missing (M) or filled (F) status at the tooth (T)/surface (S) levels were evaluated, and decayed, missing, and filled (DMF) index scores for severity, along with the Significant Caries Index (SiC), were calculated. An associated caries factor questionnaire was completed by participants.ResultsThe prevalence of caries was 98.5% for D1MFT, 79.7% for D3MFT, and 71.9% for D5MFT. The means (standard deviations) for severity were 9.2 (5.3) for D1MFT, 3.3 (3.0) for D3MFT, and 2.4 (2.4) for D5MFT, and 5.6 (2.1) for the SiC. Indicators associated with a lower risk of caries (D5MFT) were irregular dental visits (prevalence odds ratio POR = 0.45, 95% confidence interval (CI): 0.36, 0.56) and irregular use of mouthwashes (POR = 0.73, 95% CI: 0.60, 0.89).ConclusionsWe found a high caries prevalence and severity in 12 year-old children in Latvia. Although the WHO target for 2010 (D5MFT ≤ 3) is met, the values for caries prevalence (D5MFT > 0 = 71.9%) and severity (D5MFT = 2.5) in 12-year-old Latvian children are higher than the European averages (D5MFT > 0 = 52%, D5MFT = 1.1).  相似文献   
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We examine children's perceptions of the strategies they would use to resolve community health problems. Qualitative analysis using a grounded theory approach showed that 9- to 10-year-old children could conceptualize a range of solutions to hypothetical community health problems. Children's responses reflected an egocentric perspective, one that was centered on self and peers acting on short-term solutions to the immediate problem. Less frequently, children conceptualized broader structural interventions aimed at removing the problem altogether. Children could name resource persons including their friends, family, school personnel and other people in the community. However, outside of their family and peers, their knowledge was non-specific, i.e. it is doubtful that they would actually be able to access the resources. In light of our findings we discuss several important implications for future research. We note that children are interested in changing community conditions that affect their heath. However, their recognition of their marginalized position in adult society and their perception that adults do not take them seriously may be significant barriers to their participation. We suggest that society must rethink the position and roles that are assigned to children so that their valuable potential is not lost.  相似文献   
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OBJECTIVE: This study examined variations in the use of second-generation antipsychotic medication among African-American and non-Hispanic white patients in a national sample of adults who were treated by psychiatrists. METHODS: This study used data from studies of psychiatric patients and treatments that were conducted by the American Psychiatric Institute for Research and Education's (APIRE's) Practice Research Network (PRN). Psychiatrists provided detailed clinical data for 126 African-American patients and 574 white patients who were randomly selected and for whom antipsychotic medications were prescribed. The study assessed differences by race in the use of second-generation antipsychotic medication, adjusting for clinical, sociodemographic, and health-system characteristics, including patients' source of payment for treatment. RESULTS: African-American patients were less likely than white patients to receive second-generation antipsychotic medications (49 percent compared with 66 percent). After the analysis statistically adjusted for clinical, sociodemographic, and health-system characteristics, African-American patients remained less likely than white patients to receive second-generation antipsychotics. CONCLUSIONS: Because African Americans tended to receive medications that are not first-line recommended treatments and that have a greater risk of producing tardive dyskinesia and extrapyramidal side effects, African Americans could be expected to suffer diminished clinical status. This disparity may also contribute to lower rates of adherence and to more frequent emergency department visits and psychiatric hospitalizations among African Americans  相似文献   
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