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A hitherto unknown glutathione-S-transferase in human erythrocytes displays polymorphism: three quarters of the population (conjugators) possess, whereas one quarter (non-conjugators) lack this specific activity. A standard method for the identification of conjugators and non-conjugators with the use of methyl bromide and gas chromatography (head space technique) is described. Three substrates of the polymorphic enzyme, methyl bromide, ethylene oxide and dichloromethane (methylene chloride), were incubated in vitro with individual whole blood samples of conjugators and non-conjugators. All three substances led to a marked increase of sister chromatid exchanges (SCE) in the lymphocytes of the non-conjugators but not in those of conjugators. A protective effect of the glutathione-S-transferase activity in human erythrocytes for the cytogenetic toxicity of these chemicals in vitro is thus confirmed. Since the enzyme activity is not found in erythrocytes of laboratory animals, species extrapolations for risk assessment of methyl bromide, ethylene oxide and dichloromethane should be reconsidered.  相似文献   
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A healthy eating environment in the school setting is crucial to nurture the healthy eating pattern for youth. Thus, it helps to combat the obesity issue. However, the impact of healthy school environment on healthy eating habits among Asian adolescents is scarce and less clear. This clustered randomised-control study has two objectives. The first objective was to evaluate the changes in adolescents’ dietary intake after the interventions for all arms (control; healthy cooking training only; subsidization with healthy cooking training). The second objective was to compare the effect of subsidization with healthy cooking training and healthy cooking training only with the control arm on adolescents’ dietary intakes. This study consisted of 340 secondary school students aged 14 years in rural and urban Malaysia. A total of two arms of intervention and one arm of control were included. Intervention one focused on healthy cooking preparation for the canteen and convenience shop operators. Intervention two included subsidization for fruits and vegetables with a healthy cooking preparation training for the canteen and suggestions on providing healthy options to the convenience shop operators. The outcome measured was changes to dietary intake. It was measured using a three-day dietary history pre- and post-intervention. A paired-t test was used to evaluate the outcome of intervention programmes on dietary changes for all arms (control, intervention one and two). An ANCOVA test was used to investigate the effect of providing subsidization and healthy cooking preparation training to the canteen and convenience shop operators on adolescents’ dietary intakes as compared to the control arm. Overall, the reduction in energy and carbohydrates for all arms were observed. Interestingly, fat intake was significantly increased after the four-week intervention programme under healthy cooking intervention but not in the food subsidization group. When comparing between control, healthy cooking training only and subsidization with the healthy cooking training arm, there was no significant changes between arms. A robust intervention to include subsidization of healthy foods for intervention programmes at schools in a larger scale study is needed to confirm this finding.  相似文献   
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Klippel–Trénaunay syndrome (KTS) is a rare congenital disorder defined by a triad of capillary malformation, venous malformation, and soft tissue or bone hypertrophy most commonly affecting unilateral lower limbs. Due to the rarity of KTS, evidence‐based guidelines for the management of pregnancy in people with KTS are still lacking. A 34‐year‐old woman (gravidity 1; parity 0) presented at 25 weeks of gestation with malformations of the right side of her body. The extent of the KTS affecting the vulva, pelvis, and right leg was remarkable. As the prenatal MRI showed massive vascular malformations of the pelvis and vulva, we performed an elective cesarean section to avoid severe perinatal hemorrhage during a vaginal delivery. Intraoperatively, we observed varices on the parietal peritoneum within the vesico‐uterine pouch and the isthmocervical transition of the uterus, which were not identifiable in the preoperative MRI. Although KTS patients have been discouraged from pregnancy in the past because of a high risk for complications, successful and uncomplicated pregnancies are possible. For this purpose, we believe a multidisciplinary strategy that is crucial.  相似文献   
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BACKGROUND: As COBE Spectra has been replaced in many parts of the world, we describe a new protocol for low‐density lipoprotein (LDL)‐apheresis performed on familial hypercholesterolemia patients for the Spectra Optia platform. METHODS: For all procedures, after administering a bolus of heparin of 2,500 U, 10,000 U of heparin added to a 600 ml ACD‐A bag was used as anticoagulant (AC). In a first phase (A), 16 apheresis procedures with COBE Spectra using an inlet:AC ratio of 25:1 were compared to 18 LDL‐apheresis treatments with Spectra Optia at split Inlet:AC ratios of 16:1/18:1 or 20:1/25:1. Platelet activation and coagulation markers were assessed. In a follow‐up phase (B), 20 procedures on Spectra Optia using an inlet:AC ratio of 20:1 were performed. RESULTS: Although coagulation markers and platelet activation analyzed were similar in both apheresis devices used, COBE Spectra procedures did not show any visual clumping in the sets. Visual analysis of clumping was highest in the Spectra Optia's 20:1/25:1 AC regimen (5/8 procedures). For the lowest Spectra Optia, AC regimen and during the follow‐up phase reversible clump formation in the disposable set was similar (1/10 procedures). Clumping was successfully reversed in all cases by temporarily lowering the inlet:AC ratio to 18:1. Blood cell counts (WBC, Plt, Hct) were similar for both COBE Spectra and Spectra Optia procedures. Spectra Optia had a significantly higher plasma removal efficiency versus COBE Spectra (84% vs.75%, P < .05). No serious adverse events were observed. CONCLUSION: Apheresis procedures on the Spectra Optia system with low‐dose heparin‐citrate anticoagulation are feasible and safe.  相似文献   
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