Randomized controlled study of the safety and efficacy of nitrous oxide-sedated endoscopic ultrasound-guided fine needle aspiration for digestive tract diseases

AIM To evaluate the efficacy and safety of nitrous oxidesedated endoscopic ultrasound-guided fine needle aspiration. METHODS Enrolled patients were divided randomly into an experimental group(inhalation of nitrous oxide) and a control group(inhalation of pure oxygen) and heart rate, blood oxygen saturation, blood pressure, electrocardiogram(ECG) changes, and the occurrence of complications were monitored and recorded. All patients and physicians completed satisfaction questionnaires about the examination and scored the process using a visual analog scale. RESULTS There was no significant difference in heart rate, blood oxygen saturation, blood pressure, ECG changes, or complication rate between the two groups of patients(P > 0.05). However, patient and physician satisfaction were both significantly higher in the nitrous oxide compared with the control group(P < 0.05).CONCLUSION Nitrous oxide-sedation is a safe and effective option for patients undergoing endoscopic ultrasound-guided fine needle aspiration.

Effects of rock fragments on yak dung greenhouse gas emissions on the Qinghai-Tibetan Plateau

Dung deposition is an important pathway of nutrient return and redistribution in alpine grasslands of the Qinghai-Tibetan Plateau.To date,information on the greenhouse gas emissions of yak dung on alpine grasslands,especially where there are large amounts of rock fragments,is limited.Our aim,therefore,was to evaluate variations in N_2O,CH_4,and CO_2 emissions from yak dung(CCD),and compare it to dung placed on rock fragments(RCD),alpine steppe soil(CSD),and a soil and rock fragment mixture(RSD) over a 30-day incubation period.The results showed that the total N_2O emissions from treatments without soil were significantly(P < 0.05) lower than those from treatments with soil.The highest total CH_4 emissions were detected in the CSD treatment,while CH_4 losses from treatments without rock fragments were significantly(P < 0.05) greater than those with rock fragments.The total CO_2 emissions from the RSD treatment was 6.30%–12.0% lower than those in the other three treatments.The soil beneath yak dung pats elevated the globalwarming potential(GWP),while the addition of rock fragments to the soil significantly(P < 0.05) decreased the GWP by reducing emissions of the three greenhouse gases.We therefore suggest that interactions between rock fragments and alpine steppe soil are effective in decreasing yak dung greenhouse gas emissions.This finding indicates that rock fragments are an effective medium for reducing greenhouse gas emissions from dung pats,and more attention should therefore be paid to evaluate its ecological impact in future studies.These results should help guide scientific assessments of regional GHG budgets in agricultural ecosystems where the addition of livestock manure to soils with large amounts of rock fragments is common.