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PURPOSE: Gas embolism is a rare but well documented entity during operative hysteroscopy, with an incidence of 10-50%. Catastrophic outcomes occur at a rate of three in 17,000 procedures. The purpose of this report is to present a non-fatal case of gas embolism probably caused by the gaseous products of combustion. CLINICAL FEATURES: A 50-yr-old woman with a history of menorrhagia was scheduled for hysteroscopy and endometrial ablation and polypectomy. Fifteen minutes into the procedure, with the patient in lithotomy position, 20 degree head down tilt, and breathing spontaneously, a sudden oxygen desaturation occurred from 97% to 87%. The patient's end-tidal carbon dioxide dropped from 46 mmHg to 27 mmHg. The patient's breathing pattern remained normal, respiratory rate remained 11-12 breaths x min(-1) but amplitude of the reservoir bag movement was increased. Cardiovascular variables remained stable. She responded rapidly to 100% oxygen and made an uneventful recovery. Having ruled out other possible causes, we concluded gas embolism was responsible for the fall in oxygen saturation and end-tidal CO(2). CONCLUSION: With all the precautions in place to minimize the likelihood of fluid overload and ambient air embolism occurring, we surmised that products of combustion were the cause of the gas embolism. During endometrial ablation, gaseous products of combustion, mainly carbon dioxide, accumulate. The gases may then contribute to the rise in uterine pressure that occurs as irrigation fluid enters the uterus and this rise in pressure in turn encourages passage of gas into the open venous sinuses.  相似文献   
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AIDS and Behavior - South Africa maintains the world’s largest HIV prevalence, accounting for 20.4% of people living with HIV internationally. HIV Pre-exposure prophylaxis (PrEP) has...  相似文献   
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BackgroundUnder nutrition is a problem of severe magnitude in low income countries like Nigeria. Adolescent school children might also be vulnerable. The dearth of data hinders planning of school health and nutrition programmes for school children.ObjectiveTo determine the prevalence of stunting, thinness; vitamin A and iron deficiencies among adolescent students in Nsukka urban, Nigeria and to determine factors that are associated with these nutritional problems.MethodsA total of 400 participants were randomly selected from 717 students aged 12 – 18 years in 3 randomly selected secondary schools. Questionnaires, anthropometric measurements, and blood analyses were the data collection methods employed.ResultsThe prevalence of stunting was 33.3% and thinness 31.0%. Neither overweight nor obesity was observed. While 64.0% were anaemic; 44.0% had vitamin A deficiency (VAD). A total of 48.0% had both anaemia and stunting, 42% had VAD + thinness; while 40% had anaemia + VAD. Household income was a predictor of vitamin A status. Children from medium/high income households had higher odds of having VAD than those from low income households (AOR=0.14; 95% CI=0.031, 0.607; P=0.009). Household income (AOR=0.12; 95% CI=0.021, 0.671; P=0.016), and age (AOR=0.09; 95% CI=0.014, 0.587; P=0.012) were independent determinants of height-for-age status.ConclusionAmong urban adolescent students in Nigeria, stunting, thinness, anaemia and VAD were problems of public health significance. Age and household monthly income played major roles.  相似文献   
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This study assessed the effects of rifapentine or rifampin on the pharmacokinetics of a single dose of bedaquiline and its M2 metabolite in healthy subjects using a two-period single-sequence design. In period 1, subjects received a single dose of bedaquiline (400 mg), followed by a 28-day washout. In period 2, subjects received either rifapentine (600 mg) or rifampin (600 mg) from day 20 to day 41, as well as a single bedaquiline dose (400 mg) on day 29. The pharmacokinetic profiles of bedaquiline and M2 were compared over 336 h after the administration of bedaquiline alone and in combination with steady-state rifapentine or rifampin. Coadministration of bedaquiline with rifapentine or rifampin resulted in lower bedaquiline exposures. The geometric mean ratios (GMRs) and 90% confidence intervals (CIs) for the maximum observed concentration (Cmax), area under the concentration-time curve to the last available concentration time point (AUC0–t), and AUC extrapolated to infinity (AUC0–inf) of bedaquiline were 62.19% (53.37 to 72.47), 42.79% (37.77 to 48.49), and 44.52% (40.12 to 49.39), respectively, when coadministered with rifapentine. Similarly, the GMRs and 90% CIs for the Cmax, AUC0–t, and AUC0–inf of bedaquiline were 60.24% (51.96 to 69.84), 41.36% (37.70 to 45.36), and 47.32% (41.49 to 53.97), respectively, when coadministered with rifampin. The Cmax, AUC0–t, and AUC0–inf of M2 were also altered when bedaquiline was coadministered with rifapentine or rifampin. Single doses of bedaquiline, administered alone or with multiple doses of rifapentine or rifampin, were well tolerated, with no safety concerns related to coadministration. Daily administration of rifapentine to patients with tuberculosis presents the same drug interaction challenges as rifampin and other rifamycins. Strong inducers of the cytochrome P450 isoenzyme CYP3A4 should be avoided when considering the use of bedaquiline. (This study is registered at clinicaltrials.gov under identifier NCT02216331.)  相似文献   
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Background

The antioxidant properties of ethanolic root extract of pepper fruit (Donnetia tripetala), and its effect on lipid peroxidation of some fresh beef tissues during frozen storage were investigated.

Materials and Methods

The antioxidant parameters were assessed using standard methods, while malondialdehyde levels of different fresh beef tissue sections treated with the extract prior to freezing, were estimated in a colorimetric reaction with thiobarbituric acid.

Results

The H2O2-scavenging ability of the extract was similar to that of ascorbic acid, with a maximum scavenging power of 55.61 ±4.98%, and an IC50 value of 86µg/ml. The extract exhibited a concentration-dependent ferric ion-reducing power, although this was significantly lower relative to that of the ascorbic acid (p < 0.05). The total phenolic content was 212.5 ± 0.002 mg/g, while the nitric oxide-scavenging ability was 64.33 ± 0.2% after 150 min. The capacity of the extract to inhibit lipid peroxidation in frozen heart muscle slices was significantly higher than that of vitamin C (p < 0 .05), but comparable to vitamins C and E in frozen testes and kidney slices.

Conclusion

These results suggest that the root extract of D. tripetala is rich in antioxidants which can be applied to meat preservation during refrigerated storage.  相似文献   
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BackgroundGlobally, rising blood pressure is of public health concern as it is a major cause of cardiovascular diseases (CVDs), and preventable death. This study accessed the relationship of blood pressure status, dietary factors and serum electrolytes among in-school adolescents in Ilishan-Remo, Ogun State, Nigeria.MethodsA cross-sectional survey of 488 secondary school students (aged 10–19 years). Blood pressures were assessed using auscultatory method and questionnaires were used to obtain food frequency and 24-hour dietary recall data. Blood samples from volunteers were used for serum sodium and potassium assays.ResultsThe mean systolic blood pressure (SBP) increased with age, irrespective of gender. The prevalence of elevated blood pressure and hypertension among participants were 19.3% and 10.5%, respectively, with males and females having similar pattern. Dietary factors like addition of table salt to already prepared foods, higher intake of eggs, and lower intake of vegetables were associated with the development of elevated blood pressure among the adolescents. The estimated mean dietary intakes (mg/person/day) of sodium and potassium were 2289±938.7 and 1321±603.8, respectively, with majority consuming far higher (for sodium – 80%) or far below (for potassium – 95%) recommendations. The mean serum sodium (138.0±18.3 mmolL-1) and potassium (3.06±1.1 mmolL-1) were similar across genders. A significant (p<0.05) negative relationship exists between serum potassium and SBP.ConclusionsThe blood pressure status of the adolescents studied are of great concern and are somewhat negatively influenced by poor dietary and lifestyle practices. They require prompt intervention to slow down the development of CVDs in the future.  相似文献   
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Pollution of the environment by petroleum products is a common feature in oil producing nations, especially in the developing countries where the incidence of pipe line leakage and valdalization is very common. This study investigated the effects of exposure to water contaminated with very low concentration of diesel on some hematological and serum biochemical parameters of mice. A total of 20 albino mice were used for the study. The mice were allowed to drink from water contaminated with diesel 1 %, v/v for 6 weeks. Hematological and serum biochemical parameters of the mice that were exposed to the contaminated water were compared to control mice. There was a significant (p<0.05) decrease in the packed cell volume, hemoglobin concentration, red blood cell count, mean corpuscular hemoglobin, and mean corpuscular hemoglobin concentration of mice that were allowed to drink from the diesel-contaminated water. The mean corpuscular volume also increased significantly (p<0.05) in these mice. The activities of these serum enzymes; aspartate aminotransferase, alanine aminotransferase, and alkaline phosphatase increased significantly (p<0.05). Serum concentrations of total bilirubin and creatinine also increased significantly (p<0.05). The results indicate that diesel-contaminated water or products even at the lowest concentration is a threat to the environment. The health of humans and other species exposed to this environmental pollutant is adversely affected.  相似文献   
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