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101.
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Aims

To report the clinical phenotype in a series of four children from three families with the rare association of high myopia, central macular atrophy, and normal full-field electroretinography (ERG).

Methods

Four male patients were ascertained with reduced vision, nystagmus, and atrophy of the macula from early childhood. Patients underwent full ophthalmic examination, electrophysiological testing, and retinal imaging.

Results

Minimum duration of follow-up was 8 years. At last review, visual acuity ranged from 0.22 to 1.20 logMAR (6/9.5–6/95 Snellen) at a mean age of 10.5 years (median 9.5 years, range 9–14 years). Refractive error ranged from a spherical equivalent of −7.40 D to −24.00 D. Three had convergent squint. Fundus examination and imaging demonstrated bilateral macular atrophy in all patients that varied from mild atrophy of the retinal pigment epithelium (RPE) to well-demarcated, punched-out atrophic lesions of retina, RPE, and choroid. Flash ERG was normal under photopic and scotopic conditions in all patients. Pattern ERG, performed in three patients, was consistent with mild to severe macular dysfunction. Progression of the area of atrophy was evident in one patient and of the myopia in two patients but all patients had stable visual acuity.

Conclusions

Patients with congenital high myopia and macular atrophy present in infancy with reduced visual acuity and nystagmus. The macular atrophic lesions vary in size and severity but electrophysiological testing is consistent with dysfunction confined to the macula. There was no deterioration in visual acuity over 8–10 years of monitoring.  相似文献   
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Angiotensin II (Ang II) and aldosterone contribute to hypertension, oxidative stress and cardiovascular damage, but the contributions of aldosterone during Ang II‐dependent hypertension are not well defined because of the difficulty to assess each independently. To test the hypothesis that during Ang II infusion, oxidative and nitrosative damage is mediated through both the mineralocorticoid receptor (MR) and angiotensin type 1 receptor (AT1), five groups of Sprague–Dawley rats were studied: (i) control; (ii) Ang II infused (80 ng/min × 28 days); (iii) Ang II + AT1 receptor blocker (ARB; 10 mg losartan/kg per day × 21 days); (iv) Ang II + mineralocorticoid receptor (MR) antagonist (Epl; 100 mg eplerenone/day × 21 days); and (v) Ang II + ARB + Epl (Combo; × 21 days). Both ARB and combination treatments completely alleviated the Ang II‐induced hypertension, whereas eplerenone treatment only prolonged the onset of the hypertension. Eplerenone treatment exacerbated the Ang II‐mediated increase in plasma and heart aldosterone 2.3‐ and 1.8‐fold, respectively, while ARB treatment reduced both. Chronic MR blockade was sufficient to ameliorate the AT1‐mediated increase in oxidative damage. All treatments normalized protein oxidation (nitrotyrosine) levels; however, only ARB and Combo treatments completely reduced lipid peroxidation (4‐hydroxynonenal) to control levels. Collectively, these data suggest that receptor signalling, and not the elevated arterial blood pressure, is the principal culprit in the oxidative stress‐associated cardiovascular damage in Ang II‐dependent hypertension.  相似文献   
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Sport Sciences for Health - To investigate the hemodynamic responses, especially HPE following different resistance exercises RE protocols in young adult subjects. Eighty-nine men...  相似文献   
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PURPOSE OF REVIEW: Opportunistic infections contribute to morbidity and mortality after myeloablative allogeneic stem cell transplantation. The development of nonmyeloablative or toxicity-reduced conditioning regimens for allogeneic hematopoietic stem cell transplantation might change this picture significantly. These regimens are in general highly immunosuppressive, but effects on myelopoiesis and mucosal toxicities are usually reduced compared with myeloablative hematopoietic stem cell transplantation conditioning regimens. This review summarizes the infectious risks associated with each type of hematopoietic stem cell transplantation conditioning regimen, and presents the results of early clinical studies. RECENT FINDINGS: Although the data are preliminary, the results of recent studies suggest that nonmyeloablative conditioning regimens may decrease the risks of bacterial infections associated with mucosal damage and persistent neutropenia; however, risks for late viral and fungal infections persist during severe graft versus host disease. Results of several case reports and series emphasize that therapeutic outcomes of infections may be improved in patients who receive nonmyeloablative conditioning regimens. SUMMARY: Infectious risks and outcomes after hematopoietic stem cell transplantation appear to be in evolution given the introduction of alternative, nonmyeloablative conditioning regimens. Although infections remain a prominent cause of transplant-related mortality, the timing and types of infections may differ. Further studies are necessary to define appropriate preventative strategies, and to determine whether patients with ongoing infections might benefit from nonmyeloablative hematopoietic stem cell transplantation.  相似文献   
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