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排序方式: 共有1933条查询结果,搜索用时 15 毫秒
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Graefe's Archive for Clinical and Experimental Ophthalmology - The published online version contains mistake as the author's first name and last name have been interchanged as "Hild...  相似文献   
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Although magnetic resonance imaging (MRI) is a valuable aid in the initial diagnosis of multiple sclerosis (MS), quantitatively MRI has been disappointing in staging and evaluating therapy protocols by means of serial examinations. In this study, image processing algorithms were developed for the global analysis of MR images of the cerebrum. Limited three-dimensional segmentation was achieved through histogram analysis by these algorithms, which are essentially operator independent. The effects of coil response and tip angles, patient positioning, and interslice gap thicknesses were examined for 10 MS patients with repeated examinations for a total of 72 images. Effects of technique and instrumentation errors were approximately 6%, and agreement between two independent operators for measuring the total MR pixel sum from periventricular effusions and intense MS plaques was better than 97% with a standard deviation of 2.9%.  相似文献   
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Proteolysis in severe sepsis is related to oxidation of plasma protein.   总被引:2,自引:0,他引:2  
OBJECTIVE: To test the hypothesis that the oxidation of proteins is part of the mechanism of proteolysis in catabolic states. DESIGN: Prospective, observational study. SETTING: Critical care unit at a university teaching hospital, New Zealand. PATIENTS: 13 patients (6 male, 7 female; median age 61, range 26-76 years) who were admitted to the Department of Critical Care Medicine at Auckland Hospital with a diagnosis of severe sepsis. The median APACHE II score during the first 24 hours after admission was 22 (range 15-34). Control values of protein carbonyl in plasma were established in 15 healthy volunteers. INTERVENTIONS: We made serial measurements of total body protein (by neutron activation analysis) and plasma protein carbonyl (by ELISA) concentrations over a period of 10 days. MAIN OUTCOME MEASURE: Plasma protein carbonyl concentration and total body protein. RESULTS: The total amount of body protein decreased significantly over the 10 days (p < 0.001). Plasma protein carbonyl concentrations were significantly higher in the septic patients than in the control group throughout the study period (p < 0.0001). There was a significant reduction in plasma protein carbonyl concentration over the study period (p < 0.008). The early increase in the concentration of protein carbonyl formation was followed by an ongoing loss of body protein. There was a significant positive correlation between total body protein and plasma protein carbonyl (p < 0.03). CONCLUSIONS: Severe sepsis results in oxidation of plasma proteins and this precedes and is related to the loss of body protein.  相似文献   
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Blood indicators of eight vitamins (B1, B2, B6, C, E, A, B12, folate) and six minerals (Cu, Mg, Zn, Ca, P, Al) were measured in 86 athletes before and after a 7- to 8-month period of training. During this period half consumed a multivitamin/mineral supplement and a matched group took a placebo. Following the supplementation period, blood biochemical indicators of B1, B6, B12, and folate status all increased but there were no significant effects of supplementation on B2, C, E, and A, or on the blood levels of any of the minerals. The supplementation had no effect on red or white cell counts or on hemoglobin levels. Irrespective of the supplementation, some blood measures varied according to sex, females evidencing significantly higher values than males for vitamins C, E, copper, magnesium, and aluminium, with B2 being higher in males. It is concluded that 7 to 8 months of multivitamin/mineral supplementation increased the blood nutritional status of some vitamins but did not affect any blood mineral levels, and that some blood nutritional indicators may vary according to sex.  相似文献   
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OBJECTIVE: Standard lung donor criteria have been established on opinions and individual experiences rather than on existing evidence. Since the scarcity of donor organs is one of the major limitations to lung transplantation, extension of donor lung criteria might considerably increase the donor pool. This study therefore evaluates the outcome, achieved with the use of extended donors versus standard donors and aims to redefine lung donor criteria. METHODS: We performed a retrospective analysis of 98 consecutive primary lung transplantations from 94 donors from 1/2001 to 12/2002. Donors were classified as extended if they fulfilled at least one criteria: age >55 years, PaO(2) at FiO(2)/PEEP 5 <300mmHg, tobacco history >20 pack years, inhalative drug abuse, presence of infiltration on chest X-ray or purulent secretions at bronchoscopy. Recipients were stratified in two groups according to whether they received a 'standard' or 'extended' organ. Postoperative complications, extubation time, ICU and hospital stay and survival were compared. RESULTS: Twenty-three (24.5%) donors were extended. Twenty-six recipients (26.55%) received organs from extended donors. Differences in intubation times (12+/-2 days standard vs. 14+/-5 days extended, P=0.70), ICU stay (16+/-2 days standard vs. 18+/-5 days extended, P=0.74) and hospital stay (38+/-4 days standard vs. 40+/-6 days extended, P=0.71) were not statistically significant. Postoperative bleeding rates were comparable (n=14 standard vs. n=3 extended) as well as bronchial anastomotic complications (n=7 standard vs. n=3 extended). Three months survival was 88.89% in the standard group vs. 92.31% in the extended group. One year survival is comparable as well with 81.94 vs. 84.62%, respectively. CONCLUSIONS: The use of lung donors who fail to meet standard criteria does not impair short and medium term results compared to standard lung donors. The impact on long term development of BOS has yet to be evaluated. The strict application of standard lung donor criteria excludes a considerable number of lungs potentially suitable for transplantation, thus liberalisation of donor criteria might help to overcome donor shortage.  相似文献   
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We recently reported that total body fat mass is the principal determinant of bone density in normal postmenopausal women. We have now reexamined the relationships among these variables and lean mass in 68 healthy premenopausal women and 51 men. Areal bone density (BMD), fat mass, and lean mass were measured in total body scans by dual-energy, x-ray absorptiometry. In women, BMD was correlated with weight (r = 0.69), fat mass (r = 0.60), and lean mass (r = 0.55). In men, the respective correlations were 0.56, 0.26 (NS), and 0.51. Multiple regression analysis confirmed a codependence of female BMD on fat and lean masses, whereas male BMD was related only to lean mass. Because BMD is an areal not volumetric density, it is dependent on body size. The analysis was therefore repeated using BMD/height as an index of "true" density. Correlations with fat mass were little changed but those with lean mass were reduced (women) or eliminated (men). By multiple regression, female BMD/height was related to fat mass alone, and in men there was a borderline effect of fat (P = 0.05) but none of lean mass. As a second method to exclude a scale artifact, fat mass was expressed as percent body weight. It was related to BMD (r = 0.48) only in women. It is concluded that bone density is closely related to fat mass in premenopausal women, but less so in men. In both sexes, apparent relationships between BMD and lean mass are artifacts attributable to the use of areal density (which is dependent on body size) as a surrogate for volumetric density. The mechanism of this fat-bone density relationship is an important question to be addressed in bone biology.  相似文献   
10.
Whole blood samples of known methylene tetrahydrofolate reductase (MTHFR) genotypes from 24 individuals were examined at site C677T. Their amplified DNA products were assessed by two-color fluorescence cross-correlation measurements and agarose gel electrophoresis/capillary gel electrophoresis. DNA subpopulations were identified which were not associated with the proper genotype by primer combinations and cycling conditions called multiplexes. We confirmed that DNA analysis by two-color fluorescence cross-correlation measurements allowed the detection of fluorescence signals specifically associated with the proper genotypes in a mixture of amplified nontarget DNA molecules without DNA sizing. The measurement approach does not require complex, follow-up mathematical analysis and is applicable to any single nucleotide polymorphisms. The simple immunogenetic model showed how the approach works to reveal specific DNA target by preventing detection of nontarget DNA. Under those experimental conditions, a new ultrasensitive, and specific method for clinical immunologists is born.  相似文献   
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