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31.
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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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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Pregnancy and tuberculosis (TB)  To assess TB cases during pregnancy in a developing region retrospectively and to present two case reports. Objectives  Since TB cases activated by HIV infection during pregnancy are well reported in the literature, we aimed to investigate the aggressiveness of pulmonary TB among pregnant women and to assess the effects of TB on the fetus in Kutahya, an area where HIV positive cases are not seen. Materials and methods  The medical records between 2000 and 2005 of the Provincial Health Directorate and Dispensary Against Tuberculosis in Kutahya were reviewed and analyzed retrospectively. Results  Between 2000 and 2005, 667 pulmonary TB cases were examined in the Kutahya region. Of these, 106 occurred in women at reproductive ages between 20 and 44. All were HIV negative cases. In this area, five TB cases were found during pregnancy. There were three cases seen in the first trimester, but pregnancy was ended by curettage. Two women had pulmonary TB and gave birth. Five cases were evaluated as class 1 TB. During and after pregnancy, isoniazid, rifampin, ethambutol, and pyrazinamide (INH + RFP + ETB + PRZ) were used for the treatment. Resistance to anti-TB drugs was not seen during the treatment. Neither congenial nor neonatal TB was seen. Conclusion  Generally, TB is expected to be more aggressive during pregnancy. Since our cases were HIV negative, it can be thought that TB did not progress aggressively. Less aggressiveness and non-resistance to TB treatment in HIV-negative pregnant women compared with HIV-positive women were observed. Therefore, HIV infection results in greater mortality than the triple combination of human immunodeficiency virus, mycobacterium TB, and pregnancy. Besides, the advance of TB in pregnant women was not different from that in non-pregnant women in Kutahya. The fetus and the newborn were not affected. INH, RFP, ETB, and PRZ were used for therapy.  相似文献   
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AIM: This study aims to investigate the existence of any relationship between homocysteine levels and insulin resistance in Turkish women with polycystic ovary syndrome. METHODS: A case-controlled, cross-sectional, observational study was undertaken in a total of 94 infertile Turkish women who required professional help in the Department of Infertility of Dr Zekai Tahir Burak Women's Health Research and Education Hospital. The correlation between serum homocysteine with age, body mass index, hormone profile, fasting insulin and glucose concentrations and insulin resistance were examined in patients with polycystic ovary syndrome and the results were compared to those of women with normal ovaries, who served as a control group. RESULTS: The mean serum fasting glucose and insulin levels, thus insulin resistance index of women with polycystic ovary syndrome, were significantly higher than those of the control subjects. The mean serum homocysteine levels were significantly higher in women with polycystic ovary syndrome than those in the control group. A positive correlation was detected between the mean homocysteine, the insulin resistance index determined by homeostasis model assessment and the fasting insulin levels in polycystic ovary syndrome patients. CONCLUSIONS: Serum homocysteine levels are elevated in women with polycystic ovary syndrome, and this elevation is associated with the serum insulin level rather than androgen excess. The intense treatment of hyperhomocysteinemia in women with polycystic ovary syndrome might improve reproductive outcome and contribute to protection from cardiovascular risks.  相似文献   
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Objectives To investigate the effectiveness of human amniotic membrane (HAM) in the prevention of postoperative adhesion formation and to compare it with the efficacy of hyaluronate/carboxymethylcellulose (HA/CMC) membrane in a rat model. Methods Following pilot studies and computer-generated randomization, 23 female Wistar albino rats were operated on in the full study. One of the uterine horns with standard lesions was treated with either HAM (n = 13) or HA/CMC (n = 10) and the other uterine horn served as the control. Second look laparotomies were performed 2 weeks after the operations. Main outcome measures were extent, severity, degree, total adhesion scores and histopathologic characteristics of adhesions. Results Uterine horns treated with HAM had significantly lower total adhesion scores than the controls (5.15 ± 2.67 vs. 7.92 ± 1.50, P < 0.05). Total adhesion scores of uterine horns treated with HA/CMC membrane were significantly lower than those of the controls (4.30 ± 1.95 vs. 7.50 ± 1.84, P < 0.01). There were no significant differences between the HAM and HA/CMC groups regarding any adhesion scores. Conclusions HAM and HA/CMC membrane are both effective for prevention of adhesion formation in a rat uterine horn model; however, one does not seem to be more effective than the other.  相似文献   
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