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41.
OBJECTIVE: The purpose of this study was to determine plasma malondialdehyde (MDA), superoxide dismutase (SOD), soluble E-selectin (sE-selectin), fibronectin, endothelin-1 (ET-1) and nitric oxide (NO) levels in women with preeclampsia and to find out the relations of diastolic blood pressure with these variables. STUDY DESIGN: We performed a case-control study consisting of randomly selected 34 healthy pregnant women and 35 patients diagnosed as preeclampsia. Lipoperoxidation was ascertained by the formation of MDA. SOD activity was determined by the method of Sun et al. Plasma concentration of NO was estimated using colorimetric assay. Plasma ET-1 and sE-selectin were measured by enzyme-linked immunosorbent assay (ELISA). A nephelometric method for fibronectin quantitation was used. RESULTS: The mean plasma level of MDA was significantly higher and SOD was significantly lower in preeclamptic pregnancies (P<0.001). Plasma concentrations of fibronectin, sE-selectin and ET-1 were significantly increased, whereas NO was significantly decreased in women with preeclampsia than normotensive women (P<0.001). CONCLUSION: Increased plasma levels of MDA, fibronectin, sE-selectin, ET-1, and decreased plasma levels of NO and SOD in preeclamptic patients suggest that poorly perfused fetoplacental unit is the origin of oxygen free radicals and lipid peroxides.  相似文献   
42.
The effect of metformin treatment to ovarian response in cases with PCOS   总被引:6,自引:0,他引:6  
Objective. To examine the effect of metformin therapy on ovarian response in clomiphene-resistant PCOS patients. Design. Randomized prospective study. Setting. Zeynep Kamil Hospital IVF Center. Patients. Thirty-two female PCOS patients with clomiphene citrate resistance. Interventions. Test group A received 2×850 mg/day metformin therapy for 8 weeks, followed by gonadotropin induction. Only gonadotropin induction was applied to Control group B. Main outcome measures. Total gonadotropin dosage, duration of gonadotropin therapy, estradiol level on HCG-day, number of follicles with ≥16 mm diameter, number of cases with hyperstimulation development, number of cancelled cycles, endometrial thickness on HCG-day, pregnancy outcome, multiple pregnancy rate. Results. The total gonadotropin doses given to metformin-study group was significantly lower than the control group. In addition, duration of therapy, HCG level, plasma estradiol level on HCG-day in the study group was significantly lower than in the control group. Conclusions. Metformin therapy has led to a higher pregnancy outcome, as well as to a decrease in hyperstimulation risk, cycle cancellations, and multiple pregnancy rates with a lower gonadotropin dosage.  相似文献   
43.
BACKGROUND: There is one published case-control study of nail disorders in hemodialysis patients. The nail changes that occur in renal transplant recipients have not been investigated specifically. OBJECTIVE: The aim of this study was to determine prevalence rates of nail disorders in hemodialysis patients and renal transplant recipients, and to investigate whether these nail pathologies are related to hemodialysis and renal transplantation. METHODS: One hundred and eighty-two hemodialysis patients and 205 renal transplant recipients were screened for the presence of nail disorders. The findings in these groups were compared with findings in 143 healthy individuals. RESULTS: One hundred and twenty-seven patients (69.8%) in the hemodialysis group and 116 patients (56.6%) in the renal transplant recipients had at least one type of nail pathology. Absence of lunula, splinter hemorrhage, and half-and-half nails were significantly more common in the hemodialysis patients than in the renal transplant recipients. Leukonychia was significantly more frequent in the renal transplant recipients than in the hemodialysis patients and controls. CONCLUSION: Hemodialysis patients and renal transplant recipients have higher rates of nail disease than the healthy population. Renal transplantation may reduce the frequencies of splinter hemorrhage and half-and-half nails. Interestingly, leukonychia increases significantly after renal transplantation.  相似文献   
44.
Mutans streptococci are the principal bacteria isolated from children with early childhood caries (ECC). The aim of this study, therefore, was to determine the relationships between factors related to ECC with salivary mutans streptococci (MS). A total of 95 children with ECC from low-income families in rural Ankara participated in this study. Breast and/or bottle-feeding habits continued in 31.5% of the children beyond 37 months. Forty percent of the bottle-fed, 35.5% of the breast-fed, and 29.4% of the breast-and bottle-fed children continued their habits beyond 37 months. Caries prevalence was significantly related to the age and feeding habits. Eighty one percent of the children did not have a toothbrushing habit and 41% had been taking sweetened medicine. High counts of MS are determined with increasing age, bottle usage, and snacking habits. We concluded that factors related to ECC are common among Turkish children.  相似文献   
45.
OBJECTIVE: To investigate the plasma and placental levels of interleukin-10 (IL-10), transforming growth factor-beta1 (TGF-beta1), and epithelial-cadherin (E-cadherin) in normotensive and preeclamptic pregnancies. METHODS: The study population consisted of 33 women with normotensive pregnancy and 35 women with preeclampsia. Peripheral venous blood samples were collected before labor (35.3 +/- 1.1 and 34.2 +/- 3.4 weeks' gestation for normotensive and preeclamptic pregnancies, respectively), and placental tissues were obtained after delivery. Maternal plasma and placental homogenate IL-10, TGF-beta1, and E-cadherin levels were determined by enzyme-linked immunosorbent assay. RESULTS: The mean plasma and placental levels of IL-10, TGF-beta1, and E-cadherin were significantly higher in preeclamptic than normotensive patients (P <.001). The plasma and placental levels of IL-10, TGF-beta1, and E-cadherin significantly increased with the increments in diastolic blood pressure (P <.001). CONCLUSION: IL-10, TGF-beta1, and E-cadherin may be involved in the pathologic process of preeclampsia. The pathophysiologic changes associated with preeclampsia may stem in part from the overproduction of these placental mediators.  相似文献   
46.
The nature of leucocyte subpopulations expressing different cell markers around the cumulus-oocyte complex (COC) of pregnant and pseudopregnant mice was investigated in the present study. Immunolabelling for CD4, CD8, CD14, CD45 and CD163 and transmission electron microscopy were used to determine whether leucocytes differ between pregnant and pseudopregnant mice. Sexually mature female BALB/c mice (n = 36; 18 pregnant, 18 pseudopregnant) were stimulated to superovulate with pregnant mare's serum gonadotropin and human chorionic gonadotrophin, then mated with either fertile or vasectomised males. Postovulatory oocytes were collected after mating. The cumulus cell masses of the pregnant group contained spermatozoa between cells and were more variable than COCs of the pseudopregnant group. Streptavidin-biotin-peroxidase immunohistochemical labelling of the cell markers CD4, CD8, CD14, CD45 and CD163 showed that there were fewer leucocytes in the COCs of the pseudopregnant group compared with the pregnant group. Transmission electron microscopy revealed that often there were macrophage-like cells containing spermiophagic bodies between the cumulus cells. These observations suggest that, together with other cumulus cells and oviducal cells, these macrophage-like cells may be involved in removing unsuitable or excess spermatozoa and, therefore, in maintaining a suitable microenvironment for normal fertilisation.  相似文献   
47.
OBJECTIVE: To investigate the dose-related effects of theophylline in prevention of ischemia-reperfusion injury of the lung. DESIGN: Experimental study. SETTINGS: University hospital. PARTICIPANTS: Thirty Wistar rats. INTERVENTIONS: In experimental group 1 (G-I) (n = 5) 20 mg/L, in G-II (n = 5) 100 mg/L, in G-III (n = 5) 400 mg/L, and in G-IV (n = 5) 1000 mg/L of theophylline was added to modified Euro-Collins solution and perfused the lungs. Lungs were extracted without an ischemic period in control group 1 (C-I) and perfused with modified Euro-Collins solution in control group 2 (C-II). Lungs were kept in a hypothermic state for 6 hours and then ventilated for 30 minutes with 100% O(2). MEASUREMENTS AND MAIN RESULTS: Tissue levels of dien congugate (DC) and malonylaldehyde (MDA) were measured. Comparison of 6 groups revealed statistically significant differences for DC and MDA (p < 0.0001 for both comparisons). Both DC and MDA levels of C-II were found to be higher than G-III and G-IV (p = 0.008). DC and MDA levels of G-III and G-IV were significantly lower than G-I and G-II (p = 0.008 for all comparisons). CONCLUSION: The results of this study showed that 400 mg/L and 1000 mg/L of theophylline added to the modified Euro-Collins solution decreased the intermediate products of lipid peroxidation. Theophylline merits further investigation in ischemia-reperfusion studies as a potentially beneficial agent.  相似文献   
48.
This prospective study was done between February 2001 and December 2002 on 84 non-small cell lung cancer patients who were apparently operable. We selectively performed mediastinoscopy to 46 patients (54.76%, group 1) with the following indications: clinical T4 tumor, high operative risk, radiologically enlarged mediastinal lymph nodes, clinical T3 tumors with central location, radiologically identified mediastinal lymph nodes of any size with adeno or large cell carcinoma histology. Other 38 patients (45.23%, group 2) underwent thoracotomy without mediastinoscopy. Sensitivity, specificity, negative predictive value and positive predictive value of the indications were calculated. Cost analysis was done in the 84 patients and the results were compared with alternative mediastinal staging strategies (vs. routine, and vs. selectively to patients with radiologically positive mediastinal lymph nodes) if they had been applied to our population. Group 1 had higher selectivity to differentiate N2 patients (p=0.02). Sensitivity, specificity, negative predictive value and positive predictive value of indications were calculated as: 0.85, 0.54, 0.92 and 0.36, respectively. Our approach was most economical in terms of total cost per patient and money spent unnecessarily per patient. Mediastinal evaluation in operable lung cancer patients should decrease the number of surgical procedures, N2 disease found at thoracotomy and cost.  相似文献   
49.
50.
Objective: Cigarette smoking is one of the major risk factors for coronary artery disease. However, chronic smoking has additional cardiac adverse effects independent of coronary atherosclerosis. We assessed the possible effects of chronic smoking on left and right ventricular (LV, RV) long-axis function using Doppler myocardial imaging (DMI). Methods: Forty otherwise healthy smokers (mean age = 26 ± 3 years) and 40 age-matched nonsmoking controls enrolled. Standard echocardiography protocol was followed by DMI. Peak systolic (VS), early (VE) and late diastolic (VA) velocities, peak systolic strain (S), and strain rate (SR) were measured from septal, lateral, and RV free walls. Results: The baseline characteristics of two groups were similar. There were significant differences regarding Doppler myocardial velocity, S, and SR indices. Septal VE (P < 0.04), S (P < 0.0001) and SR (P < 0.02) were significantly reduced in smokers. For both lateral and RV free wall, VS (P < 0.003, P < 0.002, respectively), VE (P < 0.0001, P < 0.002, respectively), S (P < 0.0001 for both), and SR (P < 0.0001, P < 0.002, respectively) were significantly reduced in smokers. There were significant correlations between the amount of smoking and septal, lateral, and RV free wall S and SR. Conclusions: Chronic cigarette smoking causes alterations in long-axis systolic and diastolic functions of right and left ventricles in healthy young subjects. These changes can be accurately detected with Doppler myocardial velocity and SR imaging.  相似文献   
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