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81.
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   
82.
目的:对维吾尔医药孜尔克中总黄酮、微量元素及脂肪含量进行测定。方法:采用分光光度法,测定孜尔克的根和果实中总黄酮的含量。采用索氏抽提法提取并测定孜尔克的根和果实的脂肪含量。用原子吸收分光光度法测定孜尔克中根和果实中钙、铁、钠、钾、铜、锌、锰7种微量元素。结果:总黄酮在0.006~0.06mg.ml-1之间与吸光度有良好的线性关系。回归方程:C=0.0732A-0.002267(mg.ml-1)。相关系数R2=0.9916。元素测定中钙、铁含量较高。结论:本法操作简便,快速,为进一步研究和综合开发利用这一民族药材提供了依据。  相似文献   
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Protein kinase C (PKC) is a multigene family of at least ten isoforms, nine of which are expressed in brain (alpha, betaI, betaII, gamma, delta, straightepsilon, eta, zeta, iota/lambda). Our previous studies have shown that many of these PKCs participate in synaptic plasticity in the CA1 region of the hippocampus. Multiple isoforms are transiently activated in the induction phase of long-term potentiation (LTP). In contrast, a single species, zeta, is persistently activated during the maintenance phase of LTP through the formation of an independent, constitutively active catalytic domain, protein kinase Mzeta (PKMzeta). In this study, we used immunoblot and immunocytochemical techniques with isoform-specific antisera to examine the distribution of the complete family of PKC isozymes and PKMzeta in rat brain. Each form of PKC showed a widespread distribution in the brain with a distinct regional pattern of high and low levels of expression. PKMzeta, the predominant form of PKM in brain, had high levels in hippocampus, frontal and occipital cortex, striatum, and hypothalamus. In the hippocampus, each isoform was expressed in a characteristic pattern, with zeta prominent in the CA1 stratum radiatum. These results suggest that the compartmentalization of PKC isoforms in neurons may contribute to their function, with the location of PKMzeta prominent in areas notable for long-term synaptic plasticity.  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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