首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 0 毫秒
1.
Thiocyanates (SCN-) are ubiquitous in nature. There are indispensable part of host defense system that act as a substrate for lactoperoxidase (LPO). In our study we present initial data on SCN- concentration in saliva of CF patients in comparison to healthy non-smokers and healthy smokers. 5 ml of saliva was collected from each subject to a sterile tube and thiocyanate concentration was measured in each sample. The results of the measurements are presented on Fig. 1. Mean concentration of SCN- in saliva of CF patients was 0.031 +/- 0.0052 g/l, in healthy non-smokers 0.039 +/- 0.0048 g/l and in healthy smokers 0.048 +/- 0.0161 g/l. The differences between each group were statistically significant. Studies on larger group of patients and probably on different material (BALF or induced sputum) should present interesting data complementing the in vitro studies.  相似文献   

2.
Uric acid: a natural scavenger of peroxynitrite, in experimental allergic encephalomyelitis and multiple sclerosisHooper, D.C. et al. (1998)Proc. Natl. Acad. Sci. U. S. A. 95, 675–680  相似文献   

3.
Between 1995 and 2003, 15 reclamation projects using passive treatment systems were installed in a 70-km2 watershed to reduce acid mine drainage (AMD) impacts from coal mining. Six stream sites were sampled for water chemistry and benthic diatoms on 15 dates from 1996 to 2005; 1 unimpacted reference stream, 4 downstream of treatment systems, and 1 AMD-impacted site with no treatment. Our objective was to determine if diatom communities have responded to restoration by comparing temporal trends at sites downstream of treatment to concurrent trends at untreated and reference sites. Water chemistry at the sites corresponded spatially to AMD sources within the watershed. All sites below treatment had a significant increase in pH. Diatom communities provided several lines of evidence that treatment had lessen AMD impacts over the 10 year study: (1) the percentage of circumneutral taxa significantly increased at 3 of the 4 sites below treatment; (2) the percentage of circumnuetral taxa averaged for all sites below treatment increased significantly; and (3) temporal changes in community composition were significantly directional for 3 of 4 treated sites, becoming progressively more similar to reference communities. This study emphasizes the importance of long-term data sets for assessing recovery of streams following large-scale restoration.  相似文献   

4.
5.
6.
7.
8.
Acrolein, the metabolite of cyclophosphamide and ifosphamide, irritates mucous membranes and is considered pathogenetically important in hemorrhagic cystitis. Increasing fluid intake or administering sodium 2-mercaptoethanesulfonate (mesna), a thiol compound, can reduce the risk of this complication. We measured urinary acrolein concentrations using headspace-solid-phase microextraction gas chromatography and mass spectrometry (headspace-SPME-GC-MS) in 19 patients receiving cyclophosphamide and ifosphamide (36 occasions). Peak acrolein concentrations occurred at 1-12h (mean +/- S.D., 5.0+/-2.7) after starting therapy, ranging from 0.3 to 406.8 nM (39.7+/-76.7), with varying patterns over time. Maintaining high urine volume was important for preventing increases in urinary acrolein concentration, as urinary acrolein concentration tended to rise as urine volume decreased. Urinalysis detected occult blood in three cases, but the patients had no clinical symptoms of hemorrhagic cystitis. In clinical trials involving cyclophosphamide and ifosphamide, monitoring of urinary acrolein concentration could indicate when to take heightened preventive measures against hemorrhagic cystitis.  相似文献   

9.
The prevalence of nocturnal biochemical hypoglycaemia--that is, blood glucose concentrations below 3 mmol/l (55 mg/100 ml)--was evaluated in a random sample of 58 insulin dependent diabetics receiving twice daily insulin. Seventeen patients had at least one blood glucose value below 3 mmol/l (55 mg/100 ml) and five a value below 2 mmol/l (36 mg/100 ml) during the night. Both bedtime (2300) and fasting morning (0700) blood glucose concentrations were significantly lower in the group with nocturnal hypoglycaemia compared with the group without (p less than 0.00001). If the bedtime blood glucose concentration was below 6 mmol/l (108 mg/100 ml) the risk of nocturnal hypoglycaemia was 80% (95% confidence limits 51-96%). If the bedtime blood glucose concentration was above 6 mmol/l the likelihood of hypoglycaemia not occurring during the night was 88% (74-96%). The mean glycosylated haemoglobin A1c (HbA1c) concentration in the group with nocturnal biochemical hypoglycaemia (8.2 (range 5.0-12.4)%) was significantly lower than that in the group without (9.4(7.0-14.2)%) (p less than 0.02). The prevalence of nocturnal hypoglycaemia in the patients receiving twice daily insulin (29%) was compared with that in 15 patients receiving thrice daily insulin (47%) and was not found to be significantly different. The likelihood of this risk being greater with thrice daily insulin was, however, 88%. No patient with nocturnal biochemical hypoglycaemia woke up during the night with symptomatic hypoglycaemia. Nocturnal biochemical hypoglycaemia is common during twice daily treatment with insulin, and low values of HbA1c might be associated with a higher risk of such hypoglycaemia. The blood glucose concentration at bedtime is a significant predictor of nocturnal biochemical hypoglycaemia, and HbA1c values might be of help in identifying patients at risk.  相似文献   

10.
Molecular and Cellular Biochemistry -  相似文献   

11.
12.
We recently reported that the red blood cell (RBC) carbonic anhydrase I (CAI) concentration in patients with hyperthyroidism is reduced and reflects the patient's mean thyroid hormone level over the preceding months. In this study, RBC CAI concentrations were measured in patients with thyroid nodules who were receiving suppressive doses of thyroxine (group I) and compared with those obtained in patients with primary hypothyroidism receiving replacement doses of thyroxine (group 2). Of the 17 patients in group 1, 16 (94%) had elevated plasma free T4 levels, but all 17 had normal free T3 levels. Of the 17 patients in group 2, 16 (94%) had normal free T4 levels and all 17 had normal free T3 levels. Plasma TSH concentrations in group 1 were all below the lower limit of sensitivity of 0.04 mU/l. In group 2, 11 had normal and 6 had slightly elevated plasma TSH concentrations. The mean (+/- SD) RBC CAI concentration in group 1 (300 +/- 53 nmol/g Hb) was significantly lower than that in group 2 (340 +/- 57 nmol/g Hb). The RBC CAI concentration was significantly correlated with both the concentration of plasma free T4 and free T3. These observations indicate that in patients receiving suppressive doses of thyroxine a slight increase in the plasma free T4 concentration produces a slight but significant decrease in RBC CAI levels.  相似文献   

13.
The present study investigated whether thermal sweating may relieve elevated concentrations of serum uric acid or urea. Concentrations of uric acid and urea were measured in the sweat of sixteen male volunteers, who were treated with external heat after one hour of intense physical exercise. The same analytes were also measured in their urine and serum samples. Furthermore, creatinine and some electrolytes were determined in these specimens. The results show that the concentration of uric acid in the sweat is 24.5 micromol/L, which is only 6.3% of that in serum. The concentration of urea in the sweat is 22.2 mmol/L, which is 3.6 times that in serum. The results indicate that sweat uric acid concentration is quite minimal, and the estimated total uric acid excretion per day in normal physiological range is insignificant. However, the level of sweat urea was found at a much higher concentration than the serum level. No correlation could be established between the level of uric acid in sweat and in serum. There was also no correlation between the level of urea in sweat and that in serum. These results suggest it would not be effective to relieve the elevated serum uric acid concentration by thermal sweating when the renal excretion of uric acid is partly compromised. Nevertheless, the potential of urea excretion via profuse sweating is apparent particularly when the kidneys are damaged or their function is impaired. These findings also suggest that persons who take vigorous exercise or are exposed to hot environments should be well advised to drink adequate fluids since heavy sweating excretes only minimal uric acid, accompanied by significant diminution of urinary output and diminished urinary excretions of uric acid, which may induce elevated levels of serum uric acid.  相似文献   

14.
15.

Introduction  

Recent evidence suggests that uric acid (UA), regardless of crystal deposition, may play a direct pathogenic role in renal disease. We have shown that UA is an independent predictor of hypertension and cardiovascular disease (CVD), and that CVD risk factors associate with renal dysfunction, in patients with rheumatoid arthritis (RA). In this study we investigated whether UA associates with renal dysfunction in patients with RA and whether such an association is independent or mediated through other comorbidities or risk factors for renal impairment.  相似文献   

16.
Serum aluminium concentrations and biopsy specimens of bone were examined in 56 patients with end stage chronic renal failure receiving maintenance haemodialysis. Deposits of aluminium in bone specimens were often associated with low bone formation with or without osteomalacia. Serum aluminium concentrations of greater than 3.7 mumol/l (10 micrograms/100 ml) indicated a high probability of deposits of aluminium in bone specimens, although high serum concentrations did not predict the type of renal bone disease. Biopsy of the bone is the best method of detecting aluminium intoxication of bone. A serum aluminium concentration of 3.7 mumol/l should be the threshold beyond which bone biopsy should be performed to confirm an overload of aluminium and identify histological bone changes induced by aluminium.  相似文献   

17.
18.
Thyroid hormone state was assessed in a group of postmenopausal women who had received long term treatment with oestrogen. Serum concentrations of total thyroxine, triiodothyronine, and thyroxine binding globulin were raised compared with those in a control group given placebo; serum concentrations of thyroid stimulating hormone did not differ between the groups. Oestrogen treatment resulted in a significant decrease in the serum free thyroxine concentration and in the ratio of thyroxine to thyroxine binding globulin, which supports the view that oestrogen is the causative factor of the physiological reduction in free thyroid hormone during pregnancy.  相似文献   

19.
CARD15 genes carrying the 3020insC frameshift polymorphism encode a truncated CARD15 protein that is unresponsive to bacterial muramyl dipeptide, and are strongly associated with increased susceptibility to Crohn's disease (CD). In this study we established that CARD15 gene sequences encompassing the major 3020insC polymorphism could be readily amplified from the DNA found in saliva. In addition, CARD15 RNA sequences can be readily derived from the cellular component of saliva, which is primarily comprised of buccal epithelial cells. Our results demonstrate that saliva is a readily accessible source of DNA and RNA for genotyping CD patients for variants of the CARD15 gene, representing an alternative source of nucleic acid to that obtained from venous blood.  相似文献   

20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号