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1.
ObjectiveSpinal cord stimulation (SCS) is an effective treatment in failed back surgery syndrome (FBSS). We studied the effect of preimplantation opioid use on SCS outcome and the effect of SCS on opioid use during a two-year follow-up period.Materials and methodsThe study cohort included 211 consecutive FBSS patients who underwent an SCS trial from January 1997 to March 2014. Participants were divided into groups, which were as follows: 1) SCS trial only (n = 47), 2) successful SCS (implanted and in use throughout the two-year follow-up period, n = 131), and 3) unsuccessful SCS (implanted but later explanted or revised due to inadequate pain relief, n = 29). Patients who underwent explantation for other reasons (n = 4) were excluded. Opioid purchase data from January 1995 to March 2016 were retrieved from national registries.ResultsHigher preimplantation opioid doses associated with unsuccessful SCS (ROC: AUC = 0.66, p = 0.009), with 35 morphine milligram equivalents (MME)/day as the optimal cutoff value. All opioids were discontinued in 23% of patients with successful SCS, but in none of the patients with unsuccessful SCS (p = 0.004). Strong opioids were discontinued in 39% of patients with successful SCS, but in none of the patients with unsuccessful SCS (p = 0.04). Mean opioid dose escalated from 18 ± 4 MME/day to 36 ± 6 MME/day with successful SCS and from 22 ± 8 MME/day to 82 ± 21 MME/day with unsuccessful SCS (p < 0.001).ConclusionsHigher preimplantation opioid doses were associated with SCS failure, suggesting the need for opioid tapering before implantation. With continuous SCS therapy and no explantation or revision due to inadequate pain relief, 39% of FBSS patients discontinued strong opioids, and 23% discontinued all opioids. This indicates that SCS should be considered before detrimental dose escalation.  相似文献   
2.
For geochemical reasons Finland is a low-selenium area. In the 1960's several diseases associated with serious Se deficiency were observed in domestic animals. Selenium medication of animals and selenium supplementation of animal feeds from 1969 effectively eliminated these diseases. An extensive study of the trace element content of foods consumed in Finland in the 1970's demonstrated that the dietary intake of selenium was exceptionally low (25 micrograms/day/10 MJ) during the years when domestic grains were used. A study carried out in 1981 showed that supplementation of healthy middle-aged men with high selenium wheat or yeast or selenate double the glutathione peroxidase activity in platelets. Prospective epidemiological studies based on cohorts that were followed in the 1970's suggested that low selenium (less than 45 ng/ml serum) might be a risk factor for cardiovascular diseases and cancer. Technologies to increase the selenium content of foods and feeds were developed and an official decision was reached to add, starting in 1984, sodium selenate to the main fertilizers to increase the selenium content of domestic grain to about 100 micrograms/kg. This measure will increase the average selenium intake above 50 micrograms/d even in the years when grain with a high selenium content is not imported.  相似文献   
3.
A change in transplant size, which can easily be measured by ultrasound, is one indicator of acute or chronic rejection. We report here on 49 areal measurements of transplant size from a coronal section and compare the results with isotopically measured areas. The areas measured in the isotope examinations correlated well with those measured sonographically (r = 0.82) in the case of the 33 transplants with a normal perfusion index but poorly (r = 0.45) in those with an abnormal perfusion index. The sonographically measured transplant area was about 85 cm2 in cases of acute rejection, 54 cm2 in cases of chronic rejection and 62 cm2 in cases with normal or slightly impaired transplant function (creatinine level below 200 mumol). Sonography is more suitable than isotope examination for monitoring transplant size in cases with poor perfusion.  相似文献   
4.
In order to detect possible urinary tract abnormalities among wetters, assessments of previous history completed by ultrasonography of the urinary tract and uroflowmetry were obtained for 145 wetting children and a random sample of 156 sex-matched non-wetting children drawn from a population of 3,375 seven-year-olds. Ultrasonography revealed abnormalities, including both morphological ones and cases with incomplete bladder emptying, in 5 out of 73 nightwetters (6.8%, 95% confidence limit, CL, 1.1-12.6), 10 out of 72 day and day and nightwetters (hereafter daywetters) (13.9%, CL 5.9-21.9) and 4 controls (2.6%, CL 0.1-5.0), the figure for the daywetters differing significantly from that for the controls (p less than 0.01). A fractioned voiding curve was recognized in 1 nightwetter (1.4%, CL -1.3-4.0), 7 daywetters (9.7%, CL 2.9-16.6) and 7 controls (4.5%, CL 1.2-7.7) the difference between the nightwetters and daywetters being significant (p less than 0.05). Depending on the previous history and abnormal findings in ultrasonography or uroflowmetry, examinations were continued with intravenous pyelography, voiding cystography, cystoscopy and/or by cystometry. Finally, marked structural or functional disorders of the urinary tract were detected in 11 out of 72 daywetters (15.3%, CL 7.0-23.6), 1 out of 73 pure nightwetters and 1 out of 156 control children. It is concluded that imaging of the urinary tract is not necessary for pure nightwetters, while ultrasonography or uroflowmetry and more sophisticated radiological or urological methods should be focused on those children with daytime wetting and clinical symptoms of voiding disturbances.  相似文献   
5.
The present study was designed to investigate interactions between running economy and mechanics before, during, and after an individually run marathon. Seven experienced triathletes performed a 5-min submaximal running test on a treadmill at an individual constant marathon speed. Heart rate was monitored and the expired respiratory gas was analyzed. Blood samples were drawn to analyze serum creatine kinase activity (S-CK), skeletal troponin I (sTnI), and blood lactate (B-La). A video analysis was performed (200 frames · s−1) to investigate running mechanics. A kinematic arm was used to determine the external work of each subject. The results of the present study demonstrate that after the marathon, a standardized 5-min submaximal running test resulted in an increase in oxygen consumption, ventilation, and heart rate (P < 0.05), with a simultaneous decrease in the oxygen difference (%) between inspired and expired air, and respiratory exchange ratio (P < 0.05). B-La did not change during the marathon, while sTnI and S-CK values increased (P < 0.05), peaking 2 h and 2 days after the marathon, respectively. With regard to the running kinematics, a minor increase in stride frequency and a similar decrease in stride length were observed (P < 0.01). These results demonstrate clearly that weakened running economy cannot be explained by changes in running mechanics. Therefore, it is suggested that the increased physiological loading is due to several mechanisms: increased utilization of fat as an energy substrate, increased demands of body temperature regulation, and possible muscle damage. Accepted: 20 March 2000  相似文献   
6.
Summary In order to understand more fully the effect on pulmonary function of whole body exposure to cold during submaximal exercise, we measured pulmonary function indices in ten healthy male students and ten healthy male forestry workers of similar age following submaximal treadmill walking at different temperatures in a climatic chamber. After measuring the maximal aerobic capacity with a cycle ergometer test, the subjects had to walk on four separate occasions in the climatic chamber at an intensity of 70%–75% of their individual maximal heart rate; the first at normal room temperature and then randomly, either at 0°C or at −20°C, and vice versa. The duration of each walk was 8 min. Finally, each subject had to walk in the chamber at −20° C for 17 min. Flow volume spirometry was performed at room temperature 1, 5, 10, and 20 min after exercise and the values were compared to baseline values taken prior to the last walking test. There were only minor changes in pulmonary function indices following exercise at different temperatures. Only one student showed a reduction of over 15% in peak expiratory flow rate after an 8-min walk at −20° C. It seems that submaximal exercise of short duration, even at a temperature as low as −20° C, does not impair pulmonary function in healthy young men.  相似文献   
7.
In a randomized, double-blind five-year trial, we tested the efficacy of simultaneously elevating serum levels of high-density lipoprotein (HDL) cholesterol and lowering levels of non-HDL cholesterol with gemfibrozil in reducing the risk of coronary heart disease in 4081 asymptomatic middle-aged men (40 to 55 years of age) with primary dyslipidemia (non-HDL cholesterol greater than or equal to 200 mg per deciliter [5.2 mmol per liter] in two consecutive pretreatment measurements). One group (2051 men) received 600 mg of gemfibrozil twice daily, and the other (2030 men) received placebo. Gemfibrozil caused a marked increase in HDL cholesterol and persistent reductions in serum levels of total, low-density lipoprotein (LDL), and non-HDL cholesterol and triglycerides. There were minimal changes in serum lipid levels in the placebo group. The cumulative rate of cardiac end points at five years was 27.3 per 1,000 in the gemfibrozil group and 41.4 per 1,000 in the placebo group--a reduction of 34.0 percent in the incidence of coronary heart disease (95 percent confidence interval, 8.2 to 52.6; P less than 0.02; two-tailed test). The decline in incidence in the gemfibrozil group became evident in the second year and continued throughout the study. There was no difference between the groups in the total death rate, nor did the treatment influence the cancer rates. The results are in accord with two previous trials with different pharmacologic agents and indicate that modification of lipoprotein levels with gemfibrozil reduces the incidence of coronary heart disease in men with dyslipidemia.  相似文献   
8.
Selenium and immune functions in humans   总被引:3,自引:0,他引:3       下载免费PDF全文
Earlier animal experiments have shown that selenium depletion may decrease immune functions. In this human study, 40 volunteers from a population with low serum selenium concentrations were supplemented with selenium or placebo for 11 weeks. Blood samples were drawn at intervals for analysis of selenium status and immune function. At the end of the supplementation period, plasma selenium levels were 74 ng/ml in the placebo group and 169 ng/ml in the supplemented group. The improvement in selenium status was associated with a 57% increase in the activity of platelet glutathione peroxidase in the group supplemented with selenium, but there was no increase in the activity of this enzyme in the placebo-treated subjects. Immune function was measured in vitro by tests of lymphocyte and granulocyte activity. Intracellular killing of Staphylococcus aureus by granulocytes was slightly lower in the placebo group than in the selenium group at the end of the supplementation period (77.2 compared to 85.2%; P less than 0.05). No significant changes were observed in phagocytosis, chemotactic factor generation, antibody or leukocyte migration inhibitory factor production by lymphocytes, or proliferative responses to phytohemagglutinin or concanavalin A. These results suggest that the selenium deficiency of the order found in Finland and some other areas of the world has little, if any, influence on the immune functions measured in this study.  相似文献   
9.
The effect of volume reduction on vasoactive substances and their role in estimating dry weight in haemodialysis patients was studied. Plasma atrial natriuretic peptide (ANP), catecholamines, antidiuretic hormone, renin activity and serum aldosterone were measured in 12 patients before and after bicarbonate haemodialysis. Haemodynamical changes were registered and cardiac function and diameter of the inferior vena cava were measured by echocardiography before and after dialysis. Plasma concentration of ANP was significantly reduced by haemodialysis from 209 +/- 51 to 69 +/- 13 pg mL(-1) (n = 12, P < 0.05), whereas concentrations of the other hormones were unchanged. The change in the concentration of ANP did not have significant correlation with weight reduction. The concentration of ANP correlated positively with the diameter of the inferior vena cava (r = 0.70, P < 0.05) after dialysis, but not before dialysis. The concentration of ANP before or after haemodialysis or its change during dialysis did not correlate with any other biochemical parameter. The results show that plasma ANP level is decreased after volume reduction in patients with chronic renal failure, whereas other hormonal systems are unresponsive. However, plasma concentration of ANP seems to have no role in estimating dry weight in chronic haemodialysis patients.  相似文献   
10.
In this study our aims were to investigate the presence and source of catecholamines in pericardial fluid of normotensive, reserpine-treated and spontaneously hypertensive rats. We found that noradrenaline is the only detectable catecholamine present in rat pericardial fluid. The effect of reserpine 6, 12, and 214 h after pre-treatment with 5 mg kg(-1) (8.2 micromol kg(-1)) i.p. shows that the concentration of noradrenaline in pericardial fluid reflects the amount of noradrenaline released within the heart rather than the amount of noradrenaline in plasma. Using spontaneously hypertensive rats (SHR) as a model for primary hypertension we could show that the level of pericardial noradrenaline is approximately threefold in the pericardial fluid of the SHRs when compared to respective values of age-matched normotensive Wistar-Kyoto rats (WKY), suggesting that there was an increased noradrenaline overflow in the hearts of the SHRs. In conclusion, determination of the noradrenaline concentration in the pericardial fluid might provide a new method for estimating the release of noradrenaline in the heart.  相似文献   
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