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21.
Toxicity of Organotin Compounds to Activated Sludge   总被引:3,自引:0,他引:3  
Inhibition of respiration rate of activated sludge heterotrophic microorganisms was determined for tributyltin (TBT), dibutyltin (DBT), monobutyltin (MBT), and triphenyltin (TPhT). TBT, DBT, and TPhT exhibit similar acute toxicity to activated sludge, while MBT is less toxic. The effect of various experimental parameters, such as sludge age, concentrations of suspended solids, and exposure time, on toxicity was investigated. An increase in sludge age or in the concentration of suspended solids reduces the observed inibition. Longer exposure seems to increase the inhibition of TBT, DBT, and TPhT during the first hours of exposure, while later the inhibition remains constant. In the case of MBT, 24 h after exposure, the respiration rate was similar to that of the control biomass.  相似文献   
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Background and purpose

Acute stress in surgery is ubiquitous and has an immediate impact on surgical performance and patient safety. Surgeons react with several coping strategies; however, they recognise the necessity of formal stress management training. Thus, stress assessment is a direct need. Surgical simulation is a validated standardised training milieu designed to replicate real-life situations. It replicates stress, prevents biases, and provides objective metrics. The complexity of stress mechanisms makes stress measurement difficult to quantify and interpret. This systematic review aims to identify studies that have used acute stress estimation measurements in surgeons or surgical trainees during real operations or surgical simulation, and to collectively present the rationale of these tools, with special emphasis in salivary markers.

Methods

A search strategy was implemented to retrieve relevant articles from MEDLINE and SCOPUS databases. The 738 articles retrieved were reviewed for further evaluation according to the predetermined inclusion/exclusion criteria.

Results

Thirty-three studies were included in this systematic review. The methods for acute stress assessment varied greatly among studies with the non-invasive techniques being the most commonly used. Subjective and objective tests for surgeons' acute stress assessment are being presented.

Conclusion

There is a broad spectrum of acute mental stress assessment tools in the surgical field and simulation and salivary biomarkers have recently gained popularity. There is a need to maintain a consistent methodology in future research, towards a deeper understanding of acute stress in the surgical field.  相似文献   
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Human health and well-being presuppose environmental quality. Several studies have documented the indicative role of land use types in environmental quality. However, the exact role of land use composition on disease distribution has remained scientifically vague. We assessed the congruence of diseases’ distribution with land use composition, focusing on high environmental quality areas, defined as tranquil areas with view to indicating places offering well-being. Landscape composition is linked to the presence of diseases across 51 prefectures of Greece. Agricultural and natural land use types proved to be the main drivers of disease distribution. Tranquility demonstrated a strong negative correlation with population density, thus could be considered as a quantitative spatial index of life-quality. We concluded that the landscape context affects the dominance of diseases’ patterns. Special emphasis should be put on the role of tranquil areas in human health and the relative environmental health policies.  相似文献   
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Although large-scale population studies have shown that non-steroidal anti-inflammatory drugs (NSAIDs) increase the risk of myocardial infarction, this is not confirmed in patients with rheumatoid arthritis (RA). Herein, we review the litterature on the differential effects of NSAIDs on cardiovascular risk in osteoarthritis (OA) versus RA and discuss possible explanations for this discrepancy. To assess a potential additive effect of age in non-RA populations, we compared weighted mean age between RA patients and unselected NSAID users included in cohort and case–control studies that estimate the cardiovascular risk of NSAIDs, assuming that the main indication for NSAID usage in elderly populations is OA. Our hypothesis that advanced age in osteoarthtitis compared to RA patients confounds the effect of NSAIDs on cardiovasular risk was not confirmed. Several other hypotheses that can be proposed to explain this counterintuitive effect of NSAIDs on the cardiovascular risk of RA patients are discussed. We conclude that patients with RA have a lower cardiovascular disease risk associated with the use of NSAIDs, probably due to the nature of their disease per se, until further research indicates differently.  相似文献   
27.
Context/Objective: To investigate prospectively preoperative parameters that might be related to the outcome of surgically treated patients for cervical spondylotic myelopathy (CSM).

Design: Prospective study.

Setting: Single Center in Ioannina, Greece.

Participants: Thirty-six patients were included in the study. There were 21 males and 15 females, mean age 50.8 years, range 39–70 years. The mean BMI was 27.3.

Outcome measures: From each patient, we recorded age, sex, BMI, symptoms, duration of symptoms, comorbidities, lifestyle, myelopathy grade based on MRI and levels of compression. All patients completed the modified JOA (mJOA) and NPE questionnaires preoperatively and at 1, 3, 12 months and 5-years postoperatively.

Results: The mean mJOA score significant improved from 10.8?±?1.9 points preoperatively to 16.6?±?2.2 points at 12 months postoperatively. The mean mJOA score at 5-years postoperatively was 15.5?±?3 points. The difference was still highly significant. The mean NPE score significant improved from 59.8?±?12.2 points preoperatively to 28.2?±?8.5 points at 1 month, to 35.8?±?8.1 points at 3 month and to 28.2?±?8.8 points at 12 months postoperatively. Younger patients had significant higher baseline mJOA scores and significant higher mJOA scores 5-year postoperatively. No correlation was found between sex, BMI, symptom duration, baseline mJOA or myelopathy grade and outcome at 12 months or 5-year postoperatively.

Conclusion: Age was highly predictive factor of outcome for patients undergoing surgical treatment of CSM.  相似文献   
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Mesenteric panniculitis (MP) is a rare inflammatory and fibrotic disease of the mesentery of unknown etiology. It has various clinical and radiological manifestations, posing a diagnostic challenge for clinicians. Its diagnosis is indicated via radiologic imaging and is usually confirmed via peritoneal biopsies. We describe a case of a patient with histopathologically proven MP, in which steroid dependence was successfully managed with colchicine.  相似文献   
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