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Background Attempts to elucidate the pathophysiology of chronic urticaria and its relation with stress have implicated many factors among which the increased activity of the opioid system seems to be particularly interesting. Material and Methods We determined the β-endorphin serum levels in 14 patients with chronic urticaria and 15 healthy members of the medical staff of comparable age. Results The mean β-endorphin levels of our patients (15.95 ± 2.75 pmol/l) were statistically elevated (P < 0.001) compared to those of controls (8.53 ± 2.53 pmol/l). Conclusions It is suggested that the opioid system of patients with chronic urticaria is strongly activated in the chronic stage of the disease.  相似文献   
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In developing countries, maternal infections during lactation are common. In this study, we evaluated the effect of acute maternal postpartum infection on the composition of colostrum and early milk with special emphasis on milk proteins and trace elements. The study was carried out in two maternity hospitals in Lima, Peru. Subjects were normally nourished women (body mass index (BMI) > 20.0) who intended to exclusively breastfeed their child and who had fever and clinical symptoms of infection within the first 48 h postpartum ( n = 34). Non-ill women of similar characteristics were selected as controls ( n = 23). Blood and milk samples were taken on days 1 and 14 postpartum. An acute phase response was confirmed by significantly increased serum levels of C-reactive protein in infected women. Serum zinc levels increased significantly from day 1 to day 14, but were not affected by infection. Serum copper levels were significantly higher in ill women than in non-ill women on day 1. All participating women were breastfeeding on day 14. Whey protein levels, the whey/casein ratio and total protein levels decreased significantly with time, but were not affected by infection. There were no differences in milk iron or copper levels with time or infection. Milk zinc levels decreased significantly with time, but were not affected by infection. Maternal infection during the early postpartum period does not appear to adversely affect the initiation of lactation or milk protein and trace element contents.  相似文献   
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BACKGROUND: Forced training is closely implicated with free radicals production and indication of tissue damage as well as DNA oxidation. AIM: To investigate the effect of L-cysteine (L-cys) supplementation on DNA oxidative damage found in basketball players after forced training. SUBJECTS AND METHODS: Blood was obtained from 10 players pre-game (group A), post-game (group B) and after 1 month L-cys (0.5 g 24 h(-1), orally) supplementation, pre- (group C) and post-training (group D). Total antioxidant status (TAS) and the biomarker of DNA oxidative damage 8-hydroxy-2-deoxyguanosine (8-OHdG) as well as creatine kinase (CK) and lactate dehydrogenase (LDH) were measured with commercial kits. RESULTS: TAS was increased in the groups with L-cys (group C and group D). Post-exercise 8-OHdG levels, CK and LDH were remarkably lower (0.16+/-0.03 ng ml(-1), 115+/-15 U l(-1), 417+/-90 U l(-1), respectively) in group D than those in group B (0.36+/-0.05 ng ml(-1), 286+/-12 U l(-1), 688+/-88U l(-1), p<0.001, respectively). 8-OH dG levels were negatively correlated with TAS(r=-0.718, p<0.01) and positively with CK levels(r=0.590, p<0.01). CONCLUSIONS: L-cys supplementation in basketball players may reduce DNA damage induced by training. The sulfur-containing amino acid may protect muscle cells "death" by increasing TAS and the cellular defense against oxidative stress.  相似文献   
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