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BACKGROUND: Nitric oxide (NO) production catalyzed by iNOS (inducible NO synthase) is thought to take place mainly in macrophages after activation by inflammatory mediators. NO is subsequently oxidized to nitrite and nitrate, which are excreted in urine. The concentration of inflammatory mediators in small bowel biopsy specimens from patients with coeliac disease is increased. The latter could induce increased NO production by stimulation of intestinal macrophage iNOS, resulting in high levels of urinary NO oxidation products, nitrite and nitrate (NOx). AIM: In the present study we evaluated the urinary NOx/creatinine ratios in children with active coeliac disease (n = 22), coeliac disease patients on a gluten-free diet (n = 9), healthy (n = 11) and sick control children (n = 18). METHODS: The Griess reagent method was used for measuring urinary NOx. RESULTS: Median NOx/creatinine ratios of active coeliac disease patients, coeliac disease patients on a gluten-free diet, healthy and sick control patients were 1.21, 0.19, 0.10 and 0.13 mmol/mmol, respectively. All active coeliac disease patients showed increased NOx/ creatinine ratios. Urinary NOx/creatinine ratios of the active coeliac disease patients were significantly higher than those of healthy controls (p < 0.0001), sick controls (p < 0.0001) and coeliac disease patients on a gluten-free diet (p < 0.0001). CONCLUSION: The urinary NOx/creatinine ratio is increased in patients with active coeliac disease and reverts to normal on a gluten-free diet.  相似文献   
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This study assessed photophobia in patients with benign essential blepharospasm (BEB), and determined the impact of blepharospasm on activities of daily living. Utilizing a patient–researcher collaborative approach, this study was conducted in partnership with the Benign Essential Blepharospasm Research Foundation. Of 316 respondents, 94% reported light sensitivity and 25% reported severe activity limitations. Photophobia appears to be more prominent in BEB than previously thought. Light exacerbates and triggers symptoms that compromise quality of life by affecting daily activities. Collaboration with self-advocates can be an effective way to conduct questionnaire-based research. The authors recommend development of other studies that use this type of partnership.  相似文献   
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To evaluate the reliability of phosphorus-31 magnetic resonance (MR) spectroscopy in the assessment of acute testicular ischemia, vascular integrity, and spermatogenesis, the authors studied in vivo canine and primate testicles grouped as follows: group 1 testes (n = 8), in situ canine controls; group 2 (n = 11), canine testes subjected to warm ischemia; group 3, canine (n = 4) and primate (n = 4) testicles from hormone-treated animals. Group 1 control testicles showed high monophosphoester (MP) levels; low levels of inorganic phosphate (Pi), phosphodiester (PD), and phosphocreatine; and high levels of adenosine triphosphate (ATP). Group 2 testes revealed a time-dependent decay of MP/Pi ratios (from 2.1 to 0.70). Regeneration of ATP was noted in the acute reperfusion period. After 6 weeks of pituitary gonadotropin suppression, group 3 testes showed a significant decrease (P less than .05) in MP/PD ratios from a control level of 2.6 +/- 0.3 and a decrease in the MP/beta-ATP ratio from 2.4 +/- 0.1 to 1.8 +/- 0.3. P-31 MR spectroscopy appears to be a potential method for noninvasively assessing testicular ischemic injury and the metabolic integrity of spermatogenesis.  相似文献   
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Histamine and serotonin levels were measured in expired air humidity condensate (EAHC), bronchoalveolar lavage fluid and sputum of 9 patients with chronic nonobstructive bronchitis and 25 healthy controls. It was found that concentration of biogenic amines depended on the form of chronic bronchitis, activity of bronchial inflammation, characteristics of bronchial obstruction, degree of respiratory insufficiency. EAHC furnished most complete information.  相似文献   
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Concentrations of progesterone receptor (PR) and oestrogen receptor(ER) were measured by radioligand assay in decidual tissue ofwomen undergoing termination of early pregnancy (amenorrhoeaup to 49 days). Pregnancies were terminated by vacuum aspirationat 12 or 36 h after oral administration of placebo or antiprogestinRU486 in different doses. Treatment with RU486 decreased decidualPR content, the effect being observed at 12 h as well as at36 h after 600 mg RU486 and at 36 h after 3 x 25 mg RU486 givenat 12 h intervals. PR concentration 12 h after a single doseof 25 mg RU486 was not affected. ER content was unchanged at12 h after RU486 but increased 36 h after 600 mg and 3 x 25mg RU486. Our data suggest that apart from blocking progesteroneaction, RU486 may exert its abortifacient effect through decreasingthe PR concentration. The simultaneous decrease of PR concentrationand an increase of ER concentration changes the balance betweenthem in favour of ER, which might also play a role in the abortifacienteffect of RU486.  相似文献   
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