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排序方式: 共有1115条查询结果,搜索用时 15 毫秒
91.
92.
Total radical trapping antioxidant potential (TRAP) and exercise 总被引:1,自引:0,他引:1
Sharpe PC; Duly EB; MacAuley D; McCrum EE; Mulholland C; Stott G; Boreham CA; Kennedy G; Evans AE; Trinick TR 《QJM : monthly journal of the Association of Physicians》1996,89(3):223-228
The relationship between physical activity, physical fitness and total
radical trapping antioxidant potential (TRAP) was examined in the Northern
Ireland Health and Activity Survey. This was a cross-sectional population
study (n = 1600) using a two-stage probability sample of the population.
TRAP was calculated using the sum of the individual serum antioxidant
concentrations (urate, protein thiols, ascorbate, alpha tocopherol and
bilirubin) multiplied by their respective stoichiometric values. Physical
fitness was determined by estimation of VO2max by extrapolation from
submaximal oxygen uptake, and physical activity was recorded by
computer-assisted interview. Mean serum TRAP concentrations were
significantly higher in males (653 +/- 8.2 mumol/l, mean +/- SEM) compared
to females (564 +/- 8.0 mumol/l) (p < 0.0001). Both male and female
smokers had significantly lower TRAP values than non-smokers (males p <
0.0001, females p = 0.02). In females, there was a positive relationship of
TRAP with age (p < 0.001) and body mass index (p < 0.001) but a
negative relationship with physical fitness (p < 0.05). The known
beneficial effects of exercise and activity do not appear to be directly
mediated through increased antioxidant status.
相似文献
93.
94.
Rejnmark L Vestergaard P Heickendorff L Andreasen F Mosekilde L 《European journal of clinical investigation》2001,31(9):764-772
BACKGROUND: Thiazide diuretics (TD) reduce urinary calcium, bone loss and fracture risk. Loop diuretics (LD) may have opposite effects. These effects could depend on induced rhythmic changes in bone and calcium homeostasis. DESIGN: After a run-in period of 7 days, we studied (in a factorial design) the diurnal rhythms of plasma levels of calcium, phosphate, parathyroid hormone (PTH), 1,25-dihydroxyvitamin D and osteocalcin, as well as renal excretions rates of calcium, phosphate, and cross-linked N-terminal telopeptide of type 1 collagen (NTx) in 50 postmenopausal women randomized to treatment with either a thiazide diuretic (TD; bendroflumethiazide, n = 14), a loop diuretic (LD; bumetanide, n = 13), LD plus TD (bendroflumethiazide plus bumetanide, n = 11), or placebo (n = 12). RESULTS: In all four groups, all measured quantities showed a diurnal variation. LD caused a steep increase, with a subsequent decrease, in urinary calcium and plasma PTH. The mean 24 h plasma PTH concentration was increased (8.5 +/- 0.9 mmol L-1) compared with placebo (4.4 +/- 0.4 mmol L-1), whereas net 24 h renal calcium excretion did not differ from that of the placebo group due to a rebound hypocalciuria. Compared with placebo, diurnal rhythms of plasma phosphate and osteocalcin were changed with an increase during daytime and a decrease during the night. TD did not alter the diurnal rhythm of any of the measured quantities. However, the 24-h renal calcium excretion decreased, whereas the mean 24-h plasma calcium concentration increased without PTH suppression. LD plus TD caused changes similar to those observed with LD alone. CONCLUSION: One daily dose of LD increases parathyroid activity with alterations in the diurnal pattern of osteocalcin. This could indicate a potential anabolic effect of LD. 相似文献
95.
Vestergaard P Emborg C Støving RK Hagen C Mosekilde L Brixen K 《Orthopaedic nursing / National Association of Orthopaedic Nurses》2003,22(5):325-331
PURPOSE: To analyze fracture risk and bone mineral density in patients with eating disorders (anorexia nervosa, bulimia nervosa, and other eating disorders). DESIGN: Clinical overview. FINDINGS: Bone mineral density is decreased and fracture risk increased in patients with anorexia nervosa. In patients with bulimia nervosa, bone mineral is only marginally decreased and fracture risk marginally increased. In patients with other eating disorders (eating disorders not otherwise specified), bone mineral density is decreased and fracture risk increased. CONCLUSIONS: Fracture risk is increased in patients with eating disorders. An eating disorder should be suspected in severely underweight young individuals (primarily girls) presenting with fractures, especially low-energy fractures. 相似文献
96.
Signe S. Beck-Nielsen Klaus Brusgaard Lars M. Rasmussen Kim Brixen Bendt Brock-Jacobsen Mette R. Poulsen Peter Vestergaard Stuart H. Ralston Omar M. E. Albagha Sven Poulsen Dorte Haubek Hans Gjørup Hanne Hintze Mette G. Andersen Lene Heickendorff Jacob Hjelmborg Jeppe Gram 《Calcified tissue international》2010,87(2):108-119
Hypophosphatemic rickets (HR) is a group of rare disorders caused by excessive renal phosphate wasting. The purpose of this cross-sectional study of 38 HR patients was to characterize the phenotype of adult HR patients. Moreover, skeletal and endodontic severity scores were defined to assess possible gender differences in disease severity in patients with genetically verified X-linked HR. Compared to normal reference data, i.e., z = 0, HR patients had significantly lower final height, with a mean difference in z-score of ?1.9 (95% CI ?2.4 to ?1.4, P < 0.001). Compared to paired z-scores of final height, z-scores of leg length were significantly lower and those of sitting height were significantly higher (P < 0.001), resulting in disproportion as indicated by the significantly elevated sitting height ratio, mean difference in z-score of 2.6 (95% CI 2.1–3.1, P < 0.001). Z-scores of head circumference (median 1.4, range ?0.4 to 5.5, P < 0.001) and z-scores of bone mineral density (BMD) of the lumbar spine (median 1.9, range ?1.5 to 8.6, P < 0.001) were significantly elevated compared to normal reference data. The relative risk (RR) of fracture was reduced (RR = 0.34, 95% CI 0.20–0.57, P < 0.001). The skeletal severity score tended to be higher in males compared to females (P = 0.07), and no gender difference in endodontic severity was found. In conclusion, adult HR patients were characterized by short stature and were disproportioned. They had elevated BMD of the lumbar spine and a reduced risk of fractures. We found a tendency for males to be more severely affected than females. 相似文献
97.
Allan Meldgaard Lund Flemming Skovby Helle Vestergaard Mette Christensen Ernst Christensen 《Journal of inherited metabolic disease》2010,33(5):495-500
Evidence-based guidelines for monitoring patients with disorders in fatty acid oxidation (FAO) are lacking, and most protocols
are based on expert statements. Here, we describe our protocol for Danish patients. Clinical monitoring is the most important
measure and has the main aims of checking growth, development and diet and of bringing families to the clinic regularly to
remind them of their child’s risk and review how they cope and adjust, e.g. to an acute intercurrent illness. Most of these
measures are simple and can be carried out during a routine out-patient visit; we seldom do more complicated assessments by
a neuropsychologist, speech therapist, or physical and occupational therapists. Paraclinical measurements are not used for
short-chain and medium-chain disorders; electrocardiography (including 24 h monitoring) and echocardiography are done for
most patients with long-chain and carnitine transporter deficiencies. Eye examination is done in all, and liver ultrasonography
in some patients with long-chain 3-hydroxyacyl-coenzyme A dehydrogenase/tri-functional protein (LCHAD/TFP) deficiencies. Biochemical
follow-up includes determination of free carnitine and acylcarnitines. Free carnitine is measured to monitor carnitine supplementation
in patients with multiple acyl-coenzyme A dehydrogenase deficiency (MADD) and carnitine transporter deficiency (CTD) and to
follow metabolic control and disclose deficiency states in other FAO disorders. We are evaluating long-chain acylcarnitines
in patients with long-chain disorders; so far there does not seem to be any clear-cut benefit in following these levels. An
erythrocyte fatty acid profile is done in patients with long-chain disorders to test for essential fatty acid and docosahexanoic
acid (DHA) deficiencies. The measurement of creatine kinase is helpful in long-chain disorders. Ongoing follow-up and education
of the patient is important throughout life to prevent disease morbidity or death from metabolic crises. 相似文献
98.
Insaf F. Khalil Ulla Abildrup Lene H. Alifrangis Deogratius Maiga Michael Alifrangis Lotte Hoegberg Lasse S. Vestergaard Ola Per-Eric Persson Nyagonde Nyagonde Martha M. Lemnge Thor G. Theander Ib C. Bygbjerg 《Journal of pharmaceutical and biomedical analysis》2011
Artemether-lumefantrine (ARM-LUM) has in recent years become the first-line treatment for uncomplicated malaria in many Sub-Saharan African countries. Vigorous monitoring of the therapeutic efficacy of this treatment is needed. This requires high-quality studies following standard protocols; ideally, such studies should incorporate measurement of drug levels in the study patients to exclude the possibility that insufficient drug levels explain an observed treatment failure. Several methods for measuring lumefantrine (LUM) in plasma by HPLC are available; however, several of these methods have some limitations in terms of high costs and limited feasibility arising from large required sample volumes and demanding sample preparation. Therefore, we set out to develop a simpler reversed phase high performance liquid chromatography (RP-HPLC) method based on UV detection for simultaneous measurement of LUM and its major metabolite the desbutyl LUM (DL) in plasma. Halofantrine was used as an internal standard. Liquid–liquid extraction of samples was carried out using hexane–ethyl acetate (70:30, v/v). Chromatographic separation was carried out on a Synergi Polar-RP column (250 mm × 300 mm, particle size 4 μm). The mobile phase consisted of acetonitrile–0.1 M ammonium acetate buffer adjusted to pH 4.9 (85:15%, v/v). Absorbance of the compounds was monitored at 335 nm using a reference wavelength of 360 nm. Absolute extraction recovery for LUM and DL were 88% and 90%, respectively. Inter- and intraday coefficients of variation for LUM and DL were ≤10%. The lower limits of quantification for LUM and DL were 12.5 and 6.5 ng/ml, respectively. After validation, the methodology was transferred to a local laboratory in Tanga Tanzania and samples from a small subset of malaria patients were analysed for LUM. The method appears to be applicable in settings with limited facilities. 相似文献
99.
To study the effects of hypertension and other cardiovascular risk factors on risk of fractures, we carried out a case-control
study including 124,655 fracture cases and 373,962 age- and gender-matched controls. The main exposure was hypertension, stroke,
acute myocardial infarction, ischemic heart disease, atrial fibrillation, peripheral arterial disease, and deep venous thromboembolism,
and the main confounders were use of diuretics, antihypertensive drugs, organic nitrates, vitamin K antagonists, and cholesterol
lowering drugs along with other confounders. Hypertension and stroke were the only significant risk factors in both the short-term
(OR = 1.27, 95% CI = 1.20–1.34 and 1.24, and 95% CI = 1.16–1.31 for ≤3 years since diagnosis of hypertension and stroke, respectively)
and the long-term (OR = 1.11, 95% CI = 1.00–1.23 and 1.09, and 95% CI = 1.02–1.18 for > 6 years since diagnosis of hypertension
and stroke, respectively) perspective. Acute myocardial infarction, atrial fibrillation, and deep venous thromboembolism were
all associated with a transient increase in the risk of fractures within the first 3 years following diagnosis. Peripheral
arterial disease and ischemic heart disease were not associated with an increased risk of fractures. In conclusion, hypertension
and stroke seem to be the major cardiovascular risk factors for fractures, whereas acute myocardial infarction, atrial fibrillation,
and deep venous thromboembolism seem to be only minor risk factors. The fracture risk in hypertension may explain why antihypertensive
drugs as a class effect are associated with a decreased risk of fractures. These drugs may counter some of the deleterious
effects of high blood pressure. 相似文献
100.
This case–control study sought to assess the effects of diabetes and its complications on the risk of fractures. There were
124,655 fracture cases and 373,962 age- and sex-matched controls. The main exposure was diabetes and its complications, and
the main confounders were use of insulin and oral antidiabetic agents, presence of cardiovascular disease, and use of drugs
for cardiovascular disease, along with a number of other confounders. In the crude analysis, diabetes and all complications
was associated with a statistically significantly increased overall risk of fractures. The increase in risk of fractures was
higher in type 1 diabetes (T1D) than in type 2 diabetes (T2D). However, after adjustment for confounders, the difference between
T1D and T2D disappeared, and only diabetic kidney disease in T1D retained a significantly increased risk of fractures. There
was a time dependency in the risk of fractures with an early increase at <2.5 years after diagnosis. followed by a decrease
to the level of the background population from 2.5 to 5 years after diagnosis, and a limited increase in T1D but not T2D at >5 years
after diagnosis. We conclude that diabetes, whether T1D or T2D, seems to carry an increased risk of fractures, and complications
to diabetes except for diabetic kidney disease add little to the overall risk of fracture, perhaps pointing at a common risk
factor linked to the high blood glucose levels, which may weaken bone strength. 相似文献