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Background  

Ankylosing spondylitis is a chronic inflammatory rheumatic disorder which usually begins in early adulthood. The diagnosis is often delayed by many years. MR imaging has become the preferred imaging method for detection of early inflammation of the axial skeleton in ankylosing spondylitis.  相似文献   
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Epidemiological studies have shown dietary magnesium (Mg) intake and serum Mg levels to be inversely correlated with the development of atherosclerosis. We hypothesized that low levels of Mg would promote atherosclerotic plaque development in rabbits. New Zealand white rabbits (4 months old, n = 22) were fed an atherogenic diet containing 0.12% (−Mg), 0.27% (control), or 0.43% (+Mg) Mg for 8 weeks. Blood samples were obtained at baseline, 2, 4, 6, and 8 weeks and were assayed for total cholesterol, high-density lipoprotein (HDL), non-HDL, triglycerides (TG), C-reactive protein, serum Mg, and erythrocyte Mg. Aortas from −Mg had significantly more plaque, with an intima thickness 42% greater than control and 36% greater than +Mg. Serum cholesterol levels rose over time, and at 8 weeks, −Mg had the highest and +Mg the lowest total and non-HDL cholesterol and TG levels, although these results did not reach significance. Over time, serum Mg levels increased, and erythrocyte Mg levels decreased. C-reactive protein significantly increased in all groups at 4 and 6 weeks but returned to baseline levels by 8 weeks. This study supports the hypothesis that inadequate intake of Mg results in an increase in atherosclerotic plaque development in rabbits.  相似文献   
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BACKGROUND: Recently, epidemiological and clinical data have revealed important changes with regard to clinical adenovirus infection, including alterations in antigenic presentation, geographical distribution, and virulence of the virus. METHODS: In an effort to better understand the epidemiology of clinical adenovirus infection in the United States, we adopted a new molecular adenovirus typing technique to study clinical adenovirus isolates collected from 22 medical facilities over a 25-month period during 2004-2006. A hexon gene sequence typing method was used to characterize 2237 clinical adenovirus-positive specimens, comparing their sequences with those of the 51 currently recognized prototype human adenovirus strains. In a blinded comparison, this method performed well and was much faster than the classic serologic typing method. RESULTS: Among civilians, the most prevalent adenovirus types were types 3 (prevalence, 34.6%), 2 (24.3%), 1 (17.7%), and 5 (5.3%). Among military trainees, the most prevalent types were types 4 (prevalence, 92.8%), 3 (2.6%), and 21 (2.4%). CONCLUSIONS: For both populations, we observed a statistically significant increasing trend of adenovirus type 21 detection over time. Among adenovirus isolates recovered from specimens from civilians, 50% were associated with hospitalization, 19.6% with a chronic disease condition, 11% with a bone marrow or solid organ transplantation, 7.4% with intensive care unit stay, and 4.2% with a cancer diagnosis. Multivariable risk factor modeling for adenovirus disease severity found that age <7 years (odds ratio [OR], 3.2; 95% confidence interval [CI], 1.4-7.4), chronic disease (OR, 3.6; 95% CI, 2.6-5.1), recent transplantation (OR, 2.7; 95% CI, 1.3-5.2), and adenovirus type 5 (OR, 2.7; 95% CI, 1.5-4.7) or type 21 infection (OR, 7.6; 95% CI, 2.6-22.3) increased the risk of severe disease.  相似文献   
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After an appropriate dose of 3,4-didehydroretinol (vitamin A2, DR) is given orally in corn oil to retinol (R)-depleted rats, the ratio of plasma DR/R values at 3.5 h is inversely related to the liver concentration of vitamin A (Tanumihardjo & Olson, 1988). In the present study, a similar procedure, termed the modified relative dose response (MRDR) assay, was employed with rats containing a much broader range of liver reserves; ie, less than 2 to 107 nmol of vitamin A per g wet weight of liver (less than 1 to 30 micrograms/g). The DR/R ratio for 15 of 16 rats with liver reserves less than 17 nmol/g (less than 5 micrograms/g) was greater than 0.15, whereas the ratio was less than 0.15 for 7 of 8 rats with liver reserves greater than 17 nmol/g. This distribution provides sensitivity, specificity and positive predictive values of 94, 88 and 94 per cent, respectively. The DR/R ratios reached a maximal plateau in two other groups of rats between 3.5 and 8 h. At all times up to 24 h, mean DR/R ratios for vitamin A-depleted rats (45 +/- 6 nmoles of vitamin A/g liver) were approximately twice those for vitamin A-sufficient rats (230 +/- 40 nmoles of vitamin A/g liver). In three well-nourished adults, presumably with liver reserves of greater than 300 nmol/g wet weight liver (greater than 80 micrograms retinol equivalents/g), and in two young (1- and 3-years old) well-nourished children, maximal DR/R ratios were less than 0.023. In these cases, peak DR/R ratios were observed, with one possible exception, between 8 and 12 h.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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OBJECTIVE--To test in patients with a history of myocardial infarction or stroke the feasibility of four quality of life measurements--the Nottingham health profile (NHP), the heart patients psychological questionnaire (HPPQ), the sickness impact profile (SIP), and the hospital anxiety and depression scale (HAD). DESIGN--Subjects were tested and retested after an interval of 14 days: questionnaires were self assessed. SUBJECTS--Participants were randomly selected from the Rotterdam stroke data bank (stroke patients; n = 16, mean (SD) age 66.0 (11.0) years and from the population based Rotterdam study (myocardial infarction; n = 20, mean (SD) age 72.7 (7.9) years, controls; n = 17, mean (SD) age 72.8 (7.3) years. MEASUREMENTS AND MAIN RESULTS--Mean (SD) administration times for the NHP, HPPQ, SIP, and HAD were 7.9 (3.5), 10.5 (4.3), 21.0 (9.8), and 5.5 (2.8) minutes respectively. On average, the test-retest reliability was good, with Spearman correlations ranging from 0.31 to 0.95. In spite of the limited size of the study, all instruments were able to show differences between the study groups. For instance, median SIP total scores for myocardial infarction and stroke patients were 12.4 (interquartile range 7.0-19.1) and 11.4 (5.9-15.4) respectively, compared with 7.7 (3.7-11.3) in the control group (p values of 0.04 and 0.14 respectively). CONCLUSIONS--This study suggests that use of the four instruments tested may be feasible and reliable for assessing aspects of quality of life in patients with a history of a myocardial infarction or stroke.  相似文献   
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Community-acquired viral respiratory tract infections (RTI) in lung transplant recipients may have a high rate of progression to pneumonia and can be a trigger for immunologically mediated detrimental effects on lung function. A cohort of 100 patients was enrolled from 2001 to 2003 in which 50 patients had clinically diagnosed viral RTI and 50 were asymptomatic. All patients had nasopharyngeal and throat swabs taken for respiratory virus antigen detection, culture and RT-PCR. All patients had pulmonary function tests at regular intervals for 12 months. Rates of rejection, decline in forced expiratory volume (L) in 1 s (FEV-1) and bacterial and fungal superinfection were compared at the 3-month primary endpoint. In the 50 patients with RTI, a microbial etiology was identified in 33 of 50 (66%) and included rhinovirus (9), coronavirus (8), RSV (6), influenza A (5), parainfluenza (4) and human metapneumovirus (1). During the 3-month primary endpoint, 8 of 50 (16%) RTI patients had acute rejection versus 0 of 50 non-RTI patients (p=0.006). The number of patients experiencing a 20% or more decline in FEV-1 by 3 months was 9 of 50 (18%) RTI versus 0 of 50 non-RTI (0%) (p=0.003). In six of these nine patients, the decline in FEV-1 was sustained over a 1-year period consistent with bronchiolitis obliterans syndrome (BOS). Community-acquired respiratory viruses may be associated with the development of acute rejection and BOS.  相似文献   
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