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71.
Evidence of oxidative stress in full-term healthy infants   总被引:5,自引:0,他引:5  
We hypothesized that early infancy would be a time of oxidative stress due to the difficulty of adapting to ambient oxygen. Therefore, we measured levels of products of lipid peroxidation (F2-isoprostanes), antioxidant enzyme activity (catalase (CAT) and superoxide dismutase (SOD)), and ability to resist oxidative stress (ferric reducing ability of plasma (FRAP)) in full-term infants (38-42 wk) fed human milk from birth. Seventy-seven infants were followed at 1, 3.5, 6, and 12 mo of age. F2-isoprostanes in plasma declined significantly (p < 0.05) from 1 to 6 mo (160 +/- 43; 90 +/- 33; 41 +/- 27 pg/mL (mean +/- SD)). FRAP values (775 +/- 196, 723 +/- 133, 697 +/- 126, 669 +/- 145 microM) 1, 3.5, 6, and 12, respectively) declined (p = 0.06) from 1 to 3.5 mo and from 3.5 to 6 mo of age. RBC-SOD (2.7 +/- 2, 3.2 +/- 2.8, 2.1 +/- 1.8, 2.5 +/- 1.8 U, 1, 3.5, 6, 12 mo, respectively) declined from 3.5 to 6 mo. RBC-CAT (76 +/- 23, 94 +/- 28, 81 +/- 22, 85 +/- 31 U, 1, 3.5, 6, 12 mo, respectively) also declined between 3.5 and 6 mo, after a significant increase between 1 and 3.5 mo. These data suggest that the human infant is under oxidative stress early in infancy and further study may be warranted to assess the potential benefits of antioxidant supplementation for either the mother or the infant.  相似文献   
72.
73.
Zusammenfassung Die hämatogene Osteomyelitis (HOM) bei Erwachsenen ist in industrialisierten Ländern äußerst selten. Dahingegen dürfte die Morbidität in tropischen Klimazonen deutlich höher liegen, begünstigt u. a. durch Hämoglobinopathien wie Sichelzellenanämie und Thalassämie, durch die HIV-Pandemie und Tuberkulose. Pathogenetisch werden bakterielle—unspezifische und spezifische (Tb, Syphilis, Sarkoidose)—von abakteriellen Formen der HOM unterschieden (plasmazelluläre OM, sklerosierende OM, SAPHO-Syndrom). HOM durch atypische Erreger (Pilze, Viren, Parasiten) sind trotz ihrer Seltenheit differenzialdiagnostisch ebenso zu berücksichtigen wie Knochenveränderungen durch benigne und maligne Neoplasien (Ewing-Sarkom, Osteosarkom, Knochenlymphom u. a. m.). Epidemiologie und Pathologie der HOM mit Erregerspektrum, Quellgebieten, bahnenden Kofaktoren und pathomorphologischen Veränderungen werden ausführlich dargestellt, ebenso wie das aktuelle diagnostische und therapeutische Procedere.  相似文献   
74.
Pannu Y  Shownkeen H  Nockels RP  Origitano TC 《Surgical neurology》2004,62(5):463-7; discussion 467
BACKGROUND: Intracranial dural arteriovenous fistulas account for 10 to 15% of all intracranial arteriovenous malformations. Tentorial dural arteriovenous fistulas with spinal medullary venous drainage causing spinal cord myelopathy are very rare, but have been previously described. We describe a case using a cranio-orbito zygomatic approach with intraoperative angiography for the surgical treatment of a tentorial artery dural arteriovenous fistula causing spinal cord myelopathy. CASE PRESENTATION: A 42-year-old male presented complaining of a 1-year history of incoordination and dizziness and a 2-month history of progressive myelopathy with bowel and bladder incontinence. The patient had magnetic resonance imaging (MRI) performed along with cerebral and spinal angiography that revealed a right tentorial artery dural arteriovenous fistula with spinal medullary venous involvement down to T11. Angiographic embolization was attempted, but selective catheterization was unsuccessful. The patient underwent a cranio-orbito zygomatic approach with obliteration of the dural arteriovenous fistula. An intraoperative angiogram confirmed complete obliteration of the dural arteriovenous fistula. CONCLUSION: Intracranial dural arteriovenous fistulas are a rare cause of spinal cord myelopathy. When a patient presents with suspicion of spinal dural fistula and negative spinal angiography, an intracranial origin should be suspected and a cerebral angiogram performed. Skull base approaches along with intraoperative angiography provide an alternative modality for obliteration of the dural arteriovenous fistula nidus, thereby eliminating the venous congestion and hence the spinal cord ischemia.  相似文献   
75.
Is skeletal muscle oxidative capacity decreased in old age?   总被引:2,自引:0,他引:2  
In humans, decreases in cardiac output play an important role in the age-related decrease in whole-body oxidative capacity. What remains less clear is whether a decline in skeletal muscle oxidative capacity is also an inevitable consequence of aging, as a number of other factors that could affect oxidative capacity also change with age, including: physical activity, health status, fibre-type composition, rates of protein synthesis and muscle blood supply. Both in vitro studies using muscle biopsy tissue and in vivo studies using 31P-magnetic resonance spectroscopy are used to study muscular oxidative capacity. Using these methodologies, researchers have found age-associated reductions in the oxidative capacities of specific muscles. In most cases, however, the influence of physical activity has not been adequately controlled, making it difficult to evaluate the effects of age itself from those of lifestyle changes associated with aging. Upon critical evaluation of the existing literature, the following picture regarding the effect of age on muscle oxidative capacity appears: although the maximum level of muscular oxidative capacity attainable through training may decline with age, much of the age-associated decline in oxidative function is related to the reductions in fitness and/or habitual physical activity that typically occur in this population. Future studies in this area must account for the health and activity status of their study participants.  相似文献   
76.
Tait BD  Russ GR 《Transplantation》2004,77(4):627-629
The national allocation of kidneys in Australia is based on a combination of human leukocyte antigen (HLA) matching and equity factors designed to make transplantation accessible to as many patients as possible. A points system has been designed that deducts points for HLA mismatches but adds points for factors such as levels of HLA sensitization, waiting time on dialysis, and a loading for pediatric patients. Kidneys that do not reach the level of matching required for national allocation are transplanted in the donor state using both matching and waiting time criteria, which caters to minority groups with rare HLA types.  相似文献   
77.
The purpose of this study was to determine the reliability of the 1- and 3RM tests for the modified unilateral squat. Thirty untrained (22 women, 8 men) and 22 trained (12 women, 10 men) subjects participated in the study. The trained group had a minimum of 1 year lower-body training experience but had not participated in unilateral training prior to the study. After practicing proper technique with light loads, the subjects used the barbell squat to complete a 1- and 3RM pretest and posttest. In each group half of the subjects completed the 1RM tests prior to the 3RM tests while half of the subjects completed the 3RM tests first. A rest period of 48 hours was allowed between each test. Twenty subjects, randomly selected from the two groups, completed a third session of the 1RM test 3 days after the 1RM posttest. Intraclass correlation coefficients were recorded. Differences between pre- and posttest measures were determined by the paired-sample t-test. The 1- and 3RM tests were found to be significantly reliable for trained men, r = 0.98 and r = 0.97, untrained men, r = 0.99 and r = 0.97, trained women r = 0.99 and r = 0.94, and untrained women, r = 0.97 and r = 0.87, respectively. Posttest scores for the 1- and 3RM tests significantly improved above baseline levels in each group (p < 0.05). Strength scores did not significantly increase during the third 1RM test (p = 0.22). The data indicate that the modified unilateral squat can be measured with high reliability using the 1- and 3RM tests. The improved posttest scores indicate that a pretest session should take place before recording baseline measurements.

Key Points

  • The modified unilateral squat is a reliable test for trained and untrained men and women.
  • The 1RM and 3RM tests are reliable and safe for trained and untrained subjects.
  • A practice session and pretest should be conducted prior to baseline testing.
Key words: Single-leg strength, unilateral squat, resistance exercise  相似文献   
78.
Human hair as a biologic measure of exposure to persistent organic pollutants (POPs) has some advantages over the more commonly used blood and adipose tissue samples. However, one of the primary limitations is the difficulty in distinguishing between exogenous and endogenous contamination. In addition, there are currently no standardized methods for hair sample collection, washing, and chemical analysis. There is also very limited information describing the correlation between levels of organic contaminants in hair and other body compartments. To explore levels of POPs in blood and hair, samples from 10 volunteers were collected and analyzed for select organochlorine pesticides and 57 individual polychlorinated biphenyl (PCB) congeners. We demonstrated that the method for analyzing organic contaminants in human hair was reliable and reproducible. Washing hair with shampoo decreased levels of PCBs, pesticides, and lipids by 25-33% on average and up to 62% for low-chlorinated congeners. The percentage of lipids and the levels of organochlorines in hair were higher than in serum. We found strong correlation (r = 0.8) between p,p -DDE (dichlorodiphenyldichloroethylene) levels in hair and blood and moderate correlations for the more persistent PCB congeners, but no correlations or weak correlations for other organochlorines. The present study provides preliminary evidence on the utility of hair analysis for POPs; however, further larger studies are recommended before hair analysis can be successfully applied in epidemiologic studies on POPs.  相似文献   
79.
Summary. Sarizotan exhibited high affinities only to serotonin 5-HT1A receptors and dopamine DA D4>D3>D2 receptors with the profile of a 5-HT1A agonist and DA antagonist demonstrated by the inhibition of cAMP-stimulation and guinea pig ileum contraction, decreased accumulation of the 5-HT precursor 5-hydroxytryptophan and increased levels of 5-HT metabolites, increased accumulation of DA precursor dihydroxyphenylalanine (DOPA) and the reduced levels of DA metabolites in intact rats. However, sarizotan at higher doses decreased DA precursor accumulation in reserpinized rats and induced contralateral rotational behavior in unilaterally substantia nigra lesioned rats, indicating some intrinsic dopaminergic activity; at D2 receptors sarizotan may act as a partial agonist, depending on the dopaminergic impulse flow. Sarizotan represents a new approach for the treatment of extrapyramidal motor complications such as l-DOPA-induced dyskinesia in Parkinsons disease.  相似文献   
80.
Findings from previous research have argued for the dissociation of two visual-perceptual tasks traditionally thought to be mediated by the nondominant hemisphere (i.e. perceptual closure and facial discrimination). This, primarily methodological, study examined the extent to which the facial closure measure (Mooney closure faces test) involves "closure" and/or facial discrimination. A factor analysis of six visual perceptual measures, carried out separately for left brain damaged (LBDs, n=33) and right brain damaged (RBDs, n=30) patients, resulted in two relatively independent factors (i.e. a closure factor and a facial discrimination factor), with the Mooney closure faces test loading on both. The mixed factorial structure did not aid the facial closure measure's sensitivity to right-sided brain disease. Moreover, age and education intercorrelated differently with the two factors. Results argue for the use of more discrete visual-perceptual measures when examining perceptual functioning and/or right hemisphere integrity, and imply the existence of at least two discrete cortical level visual-perceptual neural systems.  相似文献   
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