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Abstract Background: Microalbuminuria has been shown to be predictive for clinical diabetic nephropathy. Renal functional reserve (RFR), as a response to protein loading in a short period of time, is a parameter to assess the ability of kidneys to increase the glomerular filtration rate (GFR). The aim of this study was to predict the early phase of diabetic nephropathy by measuring urinary albumin level and RFR capacity in patients with insulin-dependent diabetes mellitus (IDDM).
Methods: Twenty-two patients with IDDM were studied: 11 with a disease duration of less than 5 years (group 1) and 11 with a disease duration of more than 5 years (group 2). As the control group, 15 healthy children (group 3) were included in the study. At the beginning of the study, glucose was measured and the urinary albumin/creatinine ratio was calculated. Average glycosylated hemoglobin (HbA1c) over 1 year was determined. After protein loading (red meat containing 2 g/kg of protein), the creatinine clearance was calculated at each hour for a duration of 4 h. The RFR was accepted as the peak percentage increase in GFR over the baseline value.
Results: Although metabolic control in group 2 was better, the RFR in group 2 was significantly lower than in group 1 (P < 0.05). Urinary microalbumin levels between the groups did not differ (P < 0.05). In two patients in whom microalbuminuria was detected, the RFR was much lower.
Conclusions: Detecting lower RFR levels in patients with normal urinary albumin excretion, as well as in patients with microalbuminuria, may support the idea that the RFR capacity is more sensitive than microalbuminuria in assessing the early phase of diabetic nephropathy.  相似文献   
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Primary nephrotic syndrome during childhood in Turkey   总被引:3,自引:0,他引:3  
BACKGROUND: Minimal change nephrotic syndrome (MCNS) is the most common cause of primary nephrotic syndrome (NS) during childhood. However, recent studies from different countries have reported an increasing incidence of focal segmental glomerulosclerosis (FSGS) in children. METHODS: This is a retrospective study in which 392 Turkish children who were diagnosed with NS during the last 10 years and were followed for at least 2 years, were evaluated. Mean age of the study group was 4.6 +/- 3.4 years (range 0.9-16 years) and 232 were male and 160 were female. RESULTS: In total, 280 patients were diagnosed as MCNS with their initial presentations, laboratory features, and clinical course. Kidney biopsy was performed in the remaining 112 children according to current recommendations. The results showed that membranoproliferative glomerulonephritis (MPGN) was the most common histopathologic diagnosis, 38 (34%) of the 112 patients were found to have MPGN. The number diagnosed as FSGS was 26 (23%). A significant difference was found between the age groups for both MPGN and FSGS, the former being more common in children >6 years of age and the latter more frequent in children 相似文献   
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HYPOTHESIS: The goal of this experimental study was to investigate the specific effect of myringosclerosis on tympanograms in the tympanic membranes of myringotomized rats by using otomicroscopy, tympanometry, and histopathology. BACKGROUND: Myringosclerosis is a common sequela of ventilation tube treatment of otitis media with effusion. The condition involves the hyalinization and calcification of the collagen layer in certain areas of the tympanic membrane. Previous animal experiments suggest an intimate relationship between the formation of myringosclerosis and an increased oxygen concentration in the environment of the wound after myringotomy. The result of a myringotomy therefore is an increased production of free oxygen radicals, initiating irreversible tissue damage involving fibrosis, hyalin degeneration, and finally apoptosis as observed in myringosclerosis. We propose an experimental model specific for creating sclerotic plaques solely on the tympanic membrane and for performing tympanometric measurements on this pure myringosclerosis model without creating any abnormality in the middle ear to test in what proportion myringosclerosis contributes to decrease of amplitude in tympanograms. METHODS: To assess the normal tympanometric values of Wistar albino rats, the pressure and peak admittance of the left middle ears were measured using a semiquantitative computerized clinical admittance meter using a sound frequency of 226 Hz. Twelve animals were randomly selected for the myringotomy group and perforations in the left ears were created. All tympanic membrane perforations in this group had healed and closed prior to the otomicroscopic examination and no pathologic reaction was observed in the external ear canals of rats. Otomicroscopic and tympanometric measurements were carried out on Day 15 and the degree of myringosclerosis was noted before the animals were killed. Twelve specimens in the myringotomy group were histopathologically examined for the presence of myringosclerotic plaques. RESULTS: Under light microscopy, extensive sclerotic lesions were found in the tympanic membranes of the myringotomy group, and these sclerotic deposits were located in the lamina propria. The myringosclerosis occurred predominantly adjacent to the handle of the malleus, but also near the annular region. In all ears with myringosclerosis, the magnitude of the maximum admittance reduced to approximately 50% of the Day-0 values, and this reduction was statistically significant (Z=-3.061, p=0.002). CONCLUSION: The present findings in this study are consistent with the fact that the movement of the tympanic membrane is hampered by lesions of sclerotic material, resulting in a decrease of amplitude in tympanograms (such as Type As) without any effusion or inflammation in the middle ear.  相似文献   
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AIM: To evaluate baseline foveal disorganisation of retinal inner layers (DRIL) as a prognostic factor in eyes with central retinal artery occlusion (CRAO). METHODS: Twenty-eight CRAO patients who were followed-up between 2010 and 2016 were retrospectively investigated. Demographic characteristics and detailed ophthalmological examination findings of all patients were recorded. Macular thicknesses (MTs) from 5 separate spots and DRIL were measured with spectral-domain optic coherence tomography (SD-OCT). Correlations between DRIL score and logMAR converted visual acuity (VA), change in VA, patient reference time (RT), number of hyperbaric oxygen therapy (HBOT) sessions, MT and MT change were investigated. RESULTS: There was a positive correlation between the DRIL score and the final VA (r=0.787) and a negative correlation with the change in VA (r=-0.763). The RT and MT were closely related to the DRIL score. A negative correlation was found between the number of HBOT sessions and the DRIL score (r=-0.341). CONCLUSION: The DRIL score is a parameter assessed by SD-OCT, which can provide us reliable information regarding the prognosis of visual functions and response to the treatment for CRAO patients at acute phase.  相似文献   
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The petrous portion of the temporal bone is an important location of traumatic injuries as well as inflammatory and neoplastic diseases in the clinical daily routine. In addition to the articles in this issue that focus on these diseases, this article provides a short overview of the clinically relevant anatomy of the petrous portion of the temporal bone.  相似文献   
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