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1.
Background and Aims: Primary biliary cirrhosis (PBC) might be complicated by osteoporosis, whose etiology remains unknown but seems to be multifactorial. Prevalence rates of 30% to 60% for distal renal tubular acidosis (DRTA) have been reported in PBC patients, generally as incomplete DRTA. Although it is undisputed that a reduced bone mineral density (BMD) is the expected outcome among patients who have been suffering from longstanding chronic metabolic acidosis, it is unclear if incomplete DRTA is also associated with metabolic bone disease in PBC patients. The present study was undertaken to compare the BMD of PBC patients with and without DRTA.
Methods: The BMD of 23 PBC patients (11 with DRTA and 12 without), all with normal clearance of creatinine, was assessed by dual energy radiograph absorptiometry. The diagnosis of DRTA was made if the urine pH was above 5.4 in all samples after the oral acid overload, showing tubular inability to acidify urine in the presence of test-induced systemic metabolic acidosis.
Results: Densitometric signs of osteoporosis were found in 82% of DRTA cases and in 83% of patients without DRTA (difference not significant). There were no significant differences in BMD measurement, T and Z scores of patients with and without DRTA.
Conclusions: The present study could not support a correlation between the presence of DRTA and the bone loss observed in PBC patients.  相似文献   
2.
In this work we show that the pain-induced functional impairment model (PIFIR) can be used with cannulated rats as a useful procedure for pharmacokinetic/pharmacodynamic modelling. This model evaluates analgesia by measuring motor impairment of the right limb after intra-articular administration of uric acid. Time of contact with a rotating cylinder is referred to the control limb. We studied the pharmacokinetic and pharmacodynamics of naproxen after six peroral doses to Wistar rats, and we examined the adjuvant action of caffeine with naproxen. Surgery and blood sampling did not produce any difference on functional impairment either in rats without uric acid or in the dysfunction produced by uric acid. The relation between naproxen plasma concentration and the analgesic effect was obtained with few rats. Caffeine alone did not produce any significant modification in functional impairment but the co-administration significantly increased the effect of naproxen. Plasma levels of naproxen did not change when caffeine was co-administered. The PIFIR model with blood sampling is a suitable method for pharmacokinetic/pharmacodynamic relationship studies and is specially useful to characterize drug-drug interactions.  相似文献   
3.
ABSTRACT: Complement (C) and circulating immune complexes (CIC) levels were measured in 22 full-term pregnant women and 15 of their small-for-gestational-age (SGA) offspring in order to seek evidence supporting an immunological etiology for placental lesions related to idiopathic intrauterine growth retardation. We used 19 normal full-term pregnant women and 18 of their infants with birthweight above the 25th centile of the ponderal curve as a control population for this study. C levels were significantly lower in mothers of SGA infants than in controls (146.6 ± 46.6 and 183.6 ± 36.6 respectively, p < 0.01). CIC were present in the sera of 5 out of 22 mothers of the SGA group and in 3 out of the 15 infants sera. No CIC were found in the sera of mothers or infants from the control group. Placental lesions were observed in 14 out of the 22 (64%) cases studied in the SGA group and in 1 of 11 (9%) of the controls. Two placentas from SGA infants showed acute atherosis, and deposits of IgM and C3 were found in their vessel walls. These data are in favor of an immunological mechanism for intrauterine growth retardation of unknown etiology.  相似文献   
4.
The effect of nicotinic acid (NA) on sleeping time induced bya single dose of ethanol or pentobarbital was studied in rats.It was found that sleeping time was markedly reduced by NA ina dose-dependent manner. The effect was observed when NA wasadministered 10 min before or after ethanol or pentobarbital,but not when given 60 min in advance. NA did not affect therate of ethanol elimination measured up to 5 hr after ethanoladministration. Rats pretreated with NA 60 min before ethanolslept longer than controls. This latter effect was not observedwith pentobarbital. These observations, together with the knownlack of effect of high liver NAD+ levels on ethanol metabolismand the rather stable NAD+ concentration in brain cells, suggestthat the effect of NA on sleeping time is not mediated by anincrease in ethanol metabolism in liver or by NAD+ or NAD+-dependentreactions in brain. Our results are consistent with a directaction of NA, or some rapidly formed derivative, on a structureor process associated with brain cell functions or membranes.  相似文献   
5.
Alcohol dehydrogenase (ADH) has been analysed in 36 endoscopicbiopsies of normal gastric body and/or antrum mucosa, from 31individuals with an age between 17 and 79 years. Oesophageal,duodenal and oral mucosa specimens have been also examined.Stomach mucosa contains three isozyme types: the  相似文献   
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