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BACKGROUND: Although an inverse relationship between pain sensitivity and hypertension has been described, it is still unknown whether hypertension may protect against chronic musculoskeletal complaints (MSCs). The aim of this study was to evaluate the relationship between blood pressure (BP) and prevalence of chronic MSCs at various anatomical sites. METHODS: Two consecutive public health studies within the county of Nord-Tr?ndelag, Norway, were conducted between January 5, 1984, and February 15, 1986 (Nord-Tr?ndelag Health Study [HUNT] 1), and from August 1995 to June 1997 (HUNT-2). Among 46 901 adults who participated in both surveys, 24 127 (51.4%) in HUNT-2 who reported MSCs continuously for at least 3 months during the past year were defined as having chronic MSCs. The prevalence of chronic MSCs was estimated using multiple logistic regression, with odds ratio and 95% confidence interval as measures of association with systolic and diastolic BP. RESULTS: A high systolic and diastolic BP was associated with a 10% to 60% lower prevalence of chronic MSCs, and there was a strong linear trend (P<.001) of decreasing prevalence of chronic MSCs with increasing BP values. The findings were remarkably consistent at all anatomical sites, for both sexes, across all age groups, and for systolic and diastolic BP measured in HUNT-1 and HUNT-2. CONCLUSIONS: Individuals with a high BP had a lower prevalence of chronic MSCs than individuals with a normal BP. One possible explanation may be the phenomenon of hypertension-associated hypalgesia, due to an interaction between the cardiovascular and pain regulatory systems. The effect of antihypertensive medication on this interaction should be evaluated in further studies.  相似文献   
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The influence of different contraceptive techniques on the incidence of pelvic inflammatory disease (PID) in 672 patients with gonorrhoea have been studied. The lowest frequency of PID was found in patients using hormonal contraceptives (Group A), 8.8 per cent compared to 23.5 per cent in patients using intrauterine devices (Group B) and 15.1 per cent in patients using neither technique (Group C). In comparable control groups no significant differences in background factors, such as age, marital status and sexual activity were demonstrated. It is therefore concluded that the significantly lower incidence of PID in patients using hormonal contraceptives compared to the other groups and the high incidence of PID in patients using intrauterine devices is related to the contraceptive technique per se.  相似文献   
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Sixteen pregnancies at risk for Gaucher disease - six with the Norrbottnian form, one with a juvenile form with a similar clinical course to the patients from Norrbotten and nine with the infantile form - have been monitored by the assay of β-glucosidase activity in cultivated amniotic fluid cells with natural labelled glycosylceramide as substrate. Two methods of cultivation were compared in respect of their effect on the activity of lysosomal enzymes. No significant difference was found between the two marker enzymes, β-galactosidase and N -acetyl-β-glucosaminidase, but the β-glucosidase activity was significantly higher in the cells cultivated with one of the methods. In four of the pregnancies at risk, the β-glucosidase activity in the cultivated amniotic fluid cells was less than 5 % of that in the two control materials. These fetuses were regarded as affected with Gaucher disease and were aborted. Differentiation between controls and Gaucher heterozygotes was not possible in cultivated amniotic fluid cells. The diagnosis of Gaucher disease in the amniotic fluid cells was confirmed in three of the four cases by the assay of the β-glucosidase activity in the liver and brain of the aborted fetuses. The glucosylceramide content of the liver from two aborted fetuses was not augmented. The β-glucosidase activity was examined in seven placentas from pregnancies at risk for Gaucher disease and found to be in agreement with that in the cultivated amniotic fluid cells.  相似文献   
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Twelve healthy young volunteers were studied before and during intravenous administration of lidocaine at a dose rate of 2 or 4 mg/min. Five additional volunteers, who did not receive lidocaine solution but were given the same amount of physiological saline, were studied in the same manner. Heart rate, cardiac output, mean arterial blood pressure, mean right atrial blood pressure, estimated hepatic blood flow and plasma concentration of lidocaine were measured repeatedly. The results showed an increase in heart rate, cardiac output and mean arterial blood pressure, the latter two variables in relation to the plasma concentration of lidocaine. The estimated hepatic blood flow increased, partly as a result of the reduction of splanchnic vascular resistance and partly due to the stimulation of cardiac output. The decrease in splanchnic vascular resistance was proportional to the plasma concentration of lidocaine.  相似文献   
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