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11.
以1160名7~12岁儿童为研究对象,共筛查出IDA儿童269人,贫血患病率为23.19%。抽取60名IDA儿童分为二组(补铁组、安慰剂组),另选30名正常儿童为对照组。补铁前后测Hb、FEP、PWC170、RPWC170、VO2max及血乳酸浓度值。补铁前,IDA儿童反映PWC大小的各项指标值与正常儿童之间存在显著性差异;经三个月补铁后,补铁组以上各指标值恢复正常水平。结果提示:轻度IDA对7~12岁儿童PWC有明显影响,并能通过铁剂治疗得以矫正。 相似文献
12.
The authors describe their preliminary experience with the use of superparamagnetic magnetic resonance (MR) imaging contrast media for suppression of signal from flowing blood. The goal of this work was to determine if a superparamagnetic contrast agent could successfully eliminate blood signal during cardiac-gated MR imaging, thereby eliminating or reducing flow artifacts associated with the complex and variable hemodynamics within the heart chambers. Imaging and data analysis were performed in 17 dogs subjected to experimental myocardial infarction as part of a parallel project. Six doses (0.2, 1, 2, 3.5, 4, 5, and 10 mg/kg) of AMI-25, an experimental contrast agent, were used in the study. Spin-echo imaging was performed immediately before and every 5 minutes (for an average of 25 minutes) after bolus injection of the contrast agent. Variations in the image signal-to-noise ratio relative to a baseline (before injection of contrast agent) image were assessed as a function of dose and time. Preliminary results suggest that a considerable reduction in blood flow artifacts and, hence, increases in image signal-tonoise ratio can be achieved at doses greater than or equal to 3.5 mg/kg, for approximately 20 minutes after injection. Doses equal to or less than 2 mg/kg and images obtained more than 20 minutes after injection (regardless of dose) did not reliably show hemodynamic artifact suppression. 相似文献
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14.
The Laser Microprobe Mass Analyzer (LAMMA) is a sensitive instrument for identifying and localizing trace elements in tissue samples. Using LAMMA, we have examined melanin-containing neurons of the substantia nigra in patients with Parkinson's disease (PD) and controls. We found that iron significantly accumulates within neuromelanin granules of patients with PD compared to controls. Increased aluminum was found in the neuromelanin granules of 2 of 3 PD cases but in no controls. The accumulation of iron and aluminum, which are known to promote oxidant stress, may account for the selective degeneration of neuromelanin-containing neurons in PD. 相似文献
15.
Randall W. Holt Pedro J. Diaz Jeffrey L. Duerk Errol M. Bellon 《Journal of magnetic resonance imaging : JMRI》1994,4(6):809-818
A novel method for estimating the susceptibility of an object by using the magnetic resonance (MR) imaging field distortions in an external-reference water bath next to the object is described. The field measurement was obtained with a phase reconstruction from a gradient-echo acquisition. A field model of an arbitrary object in a static magnetic field was discretely calculated from geometry determined from the magnitude reconstruction. Least-squares estimation yields the susceptibility of the object. Required (and proven) assumptions include validity of superposition, object homogeneity, negligible higher-order field terms, field-model accuracy, geometric-model accuracy, and correlation of gradient-echo phase to field distortion. MR susceptometry estimation of phantoms yielded susceptibility estimates that correlated well with known values (r >.9975). This MR susceptometry method is a first step toward quantitation of iron levels through MR imaging phase information in patients with iron overload. 相似文献
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17.
Muscle cell leakage due to long distance training 总被引:3,自引:0,他引:3
K. NØrregaard Hansen J. Bjerre-Knudsen U. Brodthagen R. Jordal P. -E. Paulev 《European journal of applied physiology》1982,48(2):177-188
Summary Abnormal myoglobinemia (above 77 g/1) and free hemoglobin in plasma were found in 16 runners and in nine non runners immediately following distance running. The same abnormalities were found in six elite rowers following rowing. In parallel with the rise in myoglobin and free hemoglobin a rise was found in serum concentrations of cellular enzymes (LDH, CK, ASAT, alkaline phosphatase) and of various metabolites. We found no proteinuria nor casts in the urine. Non runners had a higher rise in serum myoglobin than runners. Competitive running caused a rise in the serum concentration of the heart specific fraction of creatine kinase in seven of the nine (healthy) elite runners. The abnormal findings are only explainable on the basis of leakage of proteins from muscle cells to the circulation in otherwise healthy, well trained persons. Myoglobinemia and a transient rhabdomyolysis is a common phenomenon in long distance running, but evidently also occurs in distance rowing. Three months of running training prevented most of the muscle damage from relaxed jogging in the nine previous non runners. Neither the observed myoglobinemia nor the hemoglobinemia resulted in any significant loss of iron in the urine.Supported by IdrÆttens Forskningsråd, Dansk IdrÆtsforbund 相似文献
18.
Summary Haematological changes were studied in cross-country skiers during a 33-week training season (7 h a week). The daily amounts of training were calculated from the duration and the intensity of the exercise and then used to estimate training responses associated with a first order transfer function. The profile of system training responses (STR) was determined by convolution between the amounts of training and a first-order transfer function. Linear regressions were used to determine correlation coefficients between STR and iron status indices. Among the values for the time constants of decay, the one giving the best fit between STR and iron status indices was chosen. A relationship was noted between on the one hand STR and changes in serum ferritin concentration ([FERR]) and on the other hand STR and change in mean cell volume (MCV). The [FERR] was decreased and MCV was increased by training. It is suggested that a decrease in [FERR] could have been related to a decrease in total body iron stores. However, large and rapid changes in [FERR] could not have been a reflection of changes in total body iron stores. Equilibrium between [FERR] and total body iron stores could have been temporarily altered by the effects of training. Moreover, iron stores did not seem to have been sufficiently depleted to restrict erythropoiesis. The MCV increased slightly in response to intense training suggesting that training enhances the proportion of young erythrocytes. 相似文献
19.
Huang E Ong WY 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2005,161(4):502-511
A gradual increase in iron occurs in the lesioned hippocampus after neuronal injury induced by the excitotoxin kainate, and the present study was carried out to investigate whether this increase in iron might be associated with changes in expression of the iron binding protein, ferritin. An increase in ferritin immunoreactivity was observed in glial cells of the hippocampus, as early as three days after intracerebroventricular injections of kainate. The number of ferritin positive cells peaked four weeks after the kainate injection, and decreased eight and twelve weeks after injection. They were found to be mostly microglia and oligodendrocytes by double immunofluorescence labeling with glial markers. A number of ferritin-labeled endothelial cells were also observed via electron microscopy. The decline in ferritin immunoreactivity four weeks after the injection of kainate is accompanied by an increase in the number of ferric and ferrous iron positive cells in the lesioned tissue. A substantial non-overlap between ferritin and iron-containing cells was observed. In particular, spherical ferric or ferrous iron-laden cells in the degenerating hippocampus were unlabeled for ferritin for long time periods after the kainate injection. An increase in iron, together with a reduced expression of iron binding proteins such as ferritin at long time intervals after kainate lesions, could result in a relative decrease in ferritin-induced ferroxidase activity and the presence of some of the iron in the ferrous form. It is postulated that this may contribute to chronic neuronal injury, following acute kainate-induced neurodegeneration. 相似文献
20.
P. Hafkemeyer M. Schupp M. Storch W. Gerok D. Hässinger 《Journal of molecular medicine (Berlin, Germany)》1994,72(2):134-136
We report on an otherwise healthy female, mother of two children, with severe decompensated liver cirrhosis due to an iron overload and Wilson's disease. The patient was considered heterozygote for hemochromatosis on the basis of the autosomal recessive inheritance for hemochromatosis, the frequency of the hemochromatosis gene, and the laboratory parameters defining her iron overload. The case is interesting because of the coincidence of Wilson's disease and excessive iron storage.
Correspondence to: D. Haussinger 相似文献