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H Jacobus Gilhuis Carien H G Beurskens Joost de Vries Henri A M Marres Ed H M Hartman Machiel J Zwarts 《Journal of clinical neurophysiology》2003,20(2):151-154
The purpose of this study was to analyze contralateral reinnervation of the facial nerve in eight patients with complete facial palsy after surgery or trauma and seven healthy volunteers. All patients had contralateral reinnervation of facial muscles as demonstrated by electrical nerve stimulation versus none of the control subjects. Four patients had facial muscle movements at the site of the damaged nerve. In one patient this was entirely the result of contralateral reinnervation, whereas the other three patients had innervation both ipsilaterally and contralaterally. This implies that renewed facial muscle activity should be examined considering the origin of the reinnervation, either contralateral or ipsilateral. Contralateral reinnervation is a common phenomenon after total facial palsy and can occur alongside ipsilateral reinnervation. It can be mistaken for adequate reinnervation of the damaged nerve, causing postponement of dynamic reconstruction therapy. 相似文献
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Nicole Y. L. Oei Bernet M. Elzinga Oliver T. Wolf Michiel B. de Ruiter Jessica S. Damoiseaux Joost P. A. Kuijer Dick J. Veltman Philip Scheltens Serge A. R. B. Rombouts 《Brain imaging and behavior》2007,1(1-2):31-41
Glucocorticoids (GCs, cortisol in human) are associated with impairments in declarative memory retrieval. Brain regions hypothesized
to mediate these effects are the hippocampus and prefrontal cortex (PFC). Our aim was to use fMRI in localizing the effects
of GCs during declarative memory retrieval. Therefore, we tested memory retrieval in 21 young healthy males in a randomized
placebo-controlled crossover design. Participants encoded word lists containing neutral and emotional words 1 h prior to ingestion
of 20 mg hydrocortisone. Memory retrieval was tested using an old/new recognition paradigm in a rapid event-related design.
It was found that hydrocortisone decreased brain activity in both the hippocampus and PFC during successful retrieval of neutral
words. These observations are consistent with previous animal and human studies suggesting that glucocorticoids modulate both
hippocampal and prefrontal brain regions that are crucially involved in memory processing.
Electronic Supplementary Material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
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Summary Sodium fluoride 10, 20, or 40 mg/kg body weight was given intraperitoneally to rats (6–11 days old and 90–95 days old). Blood
analyses showed an initial increase in plasma fluoride concentration. The subsequent decrease in fluoride was paralleled by
a decrease in total plasma calcium. These plasma concentrations were normal at blood collection 4 days after fluoride injection.
The baby rats differed from the older rats in that their initial plasma calcium was higher and that the drop in plasma calcium
concentration was less pronounced than in the old rats. A diet low in calcium and phosphate enhanced the effects of fluoride
on total plasma calcium. The data indicate that the effect of large doses of fluoride on lowering the plasma calcium level
is modified by the calcium intake. 相似文献
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The mucin histochemical and histologic features of 166 colorectal adenomatous polyps from 124 patients were studied. A majority of the polyps (62%) had a tubular growth pattern whereas 38% showed villous growth. Severe dysplasia was more frequently found in the latter group. A significant correlation (r = 0.27, P less than 0.001) was found between the severity of dysplasia and the size of the polyps. Moreover, the ratio between goblet and columnar cells was also found to decrease (P less than 0.0001) with the severity of dysplasia. Independent of the mucin stain used (periodic acid-Schiff, alcian blue, and high-iron diamine stains), mucin reactive cells were found to be negatively correlated (-0.17 less than r less than -0.44, P less than 0.01) with severity of dysplasia, especially in the tubular adenomas. These findings suggest that evaluation of mucin stain, related to dysplasia, may contribute to the assessment of premalignant and early malignant changes in adenomas of the colon. 相似文献
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Cytomegalovirus infection induces vascular injury in the rat. 总被引:8,自引:0,他引:8
The role of cytomegalovirus (CMV) in the early development of atherosclerosis was studied in a rat model. Arterial samples derived from virus-infected normo- and hypercholesterolaemic animals were investigated by light microscopy at 1, 4, 8 and 16 weeks post infection. Early atherogenic lesions comparable to those seen in non-infected hypercholesterolaemic rats were found in CMV-infected normocholesterolaemic and hypercholesterolaemic animals, starting at 1 week post infection. The changes consisted of minimal endothelial cell damage, as shown by the en face technique, and a more than 10-fold increase in the number of leukocytes adhering to the aortic intima. The increased adhesion of leukocytes was observed in infected normocholesterolaemic rats but only in the non-infected rats which were hypercholesterolaemic. The infection of hypercholesterolaemic rats did not enhance this effect although it resulted in increased migration of the leukocytes into the subendothelial space. CMV infection of normocholesterolaemic rats induced lipid accumulation in the endothelium. In these animals approximately 1% of the endothelial cells contained lipid at 1 week post infection. In the non-infected hypercholesterol-fed animals 10% of the cells contained lipid. CMV infection in these rats induced an extra increase of the lipid-containing endothelial area. The changes in the CMV infected animals largely corresponded with the intimal injury observed in the hypercholesterolaemic rats. These results support the hypothesis that CMV may be one of the factors involved in atherogenesis. 相似文献
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Joost Doornbos Peter R. Luyten Matthijs Janssen Martin Wasser Albert De Roos 《Journal of magnetic resonance imaging : JMRI》1994,4(2):165-168
Three-dimensionally localized proton-decoupled phosphorus-31 magnetic resonance (MR) spectroscopy of skeletal and cardiac muscle was performed in six patients with systemic sclerosis. Cardiac (n = 9) and skeletal (n = 6) spectra were also obtained in healthy volunteers. Metabolite ratios and intracellular pH were determined from the spectra of skeletal and cardiac muscle. The phosphocreatine-to-adenosine triphosphate ratio was normal for both skeletal and cardiac muscle in patients with systemic sclerosis. The pH values of skeletal muscle were similar in patients and control subjects (7.13 ± 0.02 vs 7.12 ± 0.01, respectively). In skeletal muscle, the inorganic phosphate-to-phosphocreatine ratio in patients was increased relative to that of control subjects (0.106 ± 0.014 vs 0.086 ± 0.006, respectively; P =.02). P-31 MR spectroscopy showed no abnormalities in the myocardium of patients with systemic sclerosis. Assessment of the inorganic phosphate-to-phosphocreatine ratio in peripheral skeletal muscle may be helpful for assessing disease activity. 相似文献
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G Knols K M Leunissen L J Spaapen F T Bosman T W vd Wiel G Kootstra J P van Hooff 《Nephrology, dialysis, transplantation》1989,4(2):137-139
The medical history of a 42-year-old patient with primary hyperoxaluria type I is presented. Primary hyperoxaluria was suspected after renal transplantation, when oxalate deposits were found in a biopsy of the kidney graft. Diagnosis of type I hyperoxaluria was confirmed by the finding that significantly increased amounts of glycolic acid and oxalic acid were excreted. Treatment of the patient with 500 mg pyridoxine daily resulted in a decrease of the excretion of oxalate to normal values. 相似文献