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Background We report the case of a 43-year-old man haemodialysed for 20 years for systemic amyloidosis who underwent an acute choroidal occlusion after a haemodialysis accident.Case report The patient had cardiac, pulmonary, neurovegetative and renal localizations of amyloidosis. He complained during a haemodialysis session of uncomfort with abdominal pain, headache, bradycardia, vomiting, confusion and blurred vision. Acute haemolytic anemia was confirmed. In the following days, eyes were red and the vision was still altered.Results Examination showed decreased visual acuity (VA) to 20/80 OU, low intraocular pressure (IOP), major vitritis and pigmentary alterations of the fundus with yellow retinal deposits. Fluorescein and indocyanine green angiographies showed amyloid retinal deposits, pigmentary alterations, normal retinal perfusion and massive choroidal hypoperfusion persisting in the late sequence. Steroid therapy was tried unsuccessfully. The situation slowly improved within 3 months with complete clearing of the vitreous opacities and stabilisation of the pigmentary alterations. VA progressively recovered to 20/30, 1 year after the onset of the disease, but IOP remained low and choroidal perfusion did not improve 2 years after the accident.Conclusion Choroidal complications of amyloidosis have never been described so far. The acute occlusion observed here was the consequence of an intravascular haemolytic event that completed the preexisting amyloid vascular infiltration.  相似文献   
154.
Antisense oligonucleotides: basic concepts and mechanisms   总被引:1,自引:0,他引:1  
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155.
The aim of this study was to examine whether the severe prolonged deficiency in marrow clonogenic progenitor cells reported after autologous stem cell transplantation (ASCT) is associated with impairment of the primitive progenitor cell compartment. We performed Dexter-type marrow cultures and limiting dilution assays with CD34(+) cells from patients 1 year and/or later after autografting with peripheral blood stem cells for non-Hodgkin's lymphoma (NHL). Flow cytometric analysis was used to assess the CD38 antigen expression and apoptotic state (7-ADD(-)/annexin-V(+) cells) of the CD34(+) cell population. We found a dramatic decrease in both clonogenic progenitor cell production and frequency of long term culture-initiating cells (LTC-IC) in all the patients tested at 1 year, even in those displaying normal progenitor cell frequency. Surprisingly, the clonogenic capacity of each LTC-IC was not increased. Flow cytometric analysis of the CD34(+) cell population confirmed this quantitative defect, with a reduction in the CD38(dim/neg) cell population but no increase in apoptosis. This defect did not improve over time up to 4 years after transplantation. In addition, qualitative abnormalities were revealed, demonstrated by decreased CD34 antigen expression, together with impaired differentiating properties of LTC-IC toward erythroid lineage at 1 year. This study indicates that both quantitative and qualitative abnormalities of the primitive progenitor cell compartment are a constant feature up to 4 years after autologous stem cell transplantation.  相似文献   
156.
OBJECTIVES: To assess the association between selected physician characteristics and suboptimal duration of antidepressant use in the older outpatient population. DESIGN: Follow-up of patients who were prescribed an antidepressant treatment by a cohort of physicians in Quebec. SETTING: Community-based older outpatient population in Quebec. PARTICIPANTS: Retrospective cohort of 1,301 general practitioners (GPs) and 236 psychiatrists followed from 1991 to 1997. MEASUREMENTS: Treatment duration of less than 180 days in 1996/97. RESULTS: Premature interruption of antidepressant treatment was very frequent (44.7%). GPs, physicians who practice in metropolitan or urban regions, and those who have a proportion of older patients in their practice of less than 50% show a higher rate of premature interruption. These associations could not be accounted for by the choice of products, dosage, or patient characteristics. CONCLUSION: We have identified physician characteristics that are associated with suboptimal duration of antidepressant use and conclude that further interventions should target subgroups of physicians.  相似文献   
157.
We report a 3-year, 5-month-old boy with an adrenocortical carcinoma. These tumours are rare and highly malignant in childhood. In most cases they are functional, secreting adrenocortical hormones. In this case there was a misleading coexistence with a second abdominal neoplasm, which was a ganglioneuroma; this is a rare benign tumour arising from the sympathetic nervous system. The imaging investigations and their findings are discussed and correlated with pathology. Received: 15 January 1997 Accepted: 15 October 1997  相似文献   
158.
Ptak R  Valenza N  Schnider A 《Neuropsychologia》2002,40(13):2199-2205
Visual extinction, the failure of patients with unilateral focal brain damage to report the contralesional of two simultaneously presented stimuli, may be modulated by characteristics of the display such as similarity, collinearity, or connectedness. Since these factors affect the perceptual configuration of stimuli, the modulation of extinction is believed to reflect low-level perceptual grouping. In the present study, patient AG did not show any modulation of contralesional detection when the ipsilesional and contralesional stimulus grouped by colour, by form, or both (Experiment 1). In contrast, identification of the contralesional stimulus was facilitated when the stimuli grouped (Experiment 2), suggesting a modulation of extinction by specific task demands. Experiment 3 used a cueing procedure to demonstrate modulation of extinction by expectation biases. Prior to stimulus presentation, AG was cued to attend to a particular feature (e.g. colour). After stimulus exposure he was prompted to identify the expected feature on valid trials and the unexpected feature on invalid trials. AG showed a significant validity effect for contralesional stimuli i.e. he identified the expected feature (e.g. colour) significantly better than the unexpected feature (e.g. form). These results suggest that competition for selection between visual stimuli may not only be influenced by perceptual characteristics of the display, but also by high-level factors such as the response criterion or expectation biases.  相似文献   
159.
Jette N  Veregin T  Guberman A 《Neurology》2002,59(2):275-276
A 33-year-old man with complex partial seizures developed de novo hypertension after the initiation of carbamazepine, which resolved on discontinuation. Although rare, a variety of cardiovascular effects including hypertension have been reported with carbamazepine. Numerous mechanisms may be responsible; however, shared pharmacologic properties with the tricyclic antidepressants are suspect. Hypertension is a rare side effect of carbamazepine.  相似文献   
160.
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