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41.
The present study was designed to examine the effect of intra-abdominal pressure level on gastric intramucosal pH using gastric tonometry during pneumoperitoneum. One hundred patients were prospectively randomized into 5 equal groups (N = 20 each). Intra-abdominal pressure levels were 8, 10, 12, 14, and 16 mm Hg in groups I, II, III, IV, and V, respectively. Intramucosal pH measurement was done 2 times: 30 minutes following insufflation and 1 hour after the ending of the surgery. In the first and second measurements, intramucosal pH values were found as 7.39 +/- 0.02 and 7.36 +/- 0.03 in group I; 7.41 +/- 0.03 and 7.38 +/- 0.03 in group II; 7.37 +/- 0.03 and 7.37 +/- 0.03 in group III; 7.36 +/- 0.03 and 7.37 +/- 0.03 in group IV; and 7.39 +/- 0.03, 7.36 +/- 0.03 in group V, respectively. Statistical significance was not found in the comparison of these values within the groups and between the groups (P > 0.005, for each). In conclusion, intra-abdominal pressure between 8 and 16 mm Hg did not cause significant difference in gastric intramucosal pH.  相似文献   
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43.

Introduction

Pulse pressure (PP) has been reported as an independent predictor of cardiovascular mortality in hemodialysis patients. In this study, we aimed to investigate association of PP with echocardiographic and vascular structural changes such as atherosclerosis and arterial calcifications in HD patients.

Patients and methods

In this cross-sectional study, 108 chronic hemodialysis patients (49 male, 59 female, mean age: 46?±?13?years) were included. Biochemical analyses, echocardiographic and high-resolution carotid Doppler examinations were done. Aortic wall and coronary artery calcifications were measured with electron beam computed tomography. The degree of carotid artery stenosis was measured at four different sites (communis, bulbus, interna and externa) in both carotid arteries.

Results

PP was strongly correlated with systolic (r: 0.82) and diastolic (r: 0.33) blood pressure, left ventricular mass index (r: 0.58), left ventricle end diastolic diameter (r: 0.38) and weakly correlated with aortic wall calcification score (r: 0.26) and carotid plaque score (r: 0.27), but not with coronary artery calcification score. Patients with carotid plaque had higher PP than patients without plaque (50?±?16?mmHg versus 44?±?14?mmHg, P?=?0.05). Patients were divided into three groups according to aortic wall calcification score. PP was significantly higher in patients with higher aortic wall calcification (54?±?16?mmHg) than patients with lower aortic wall calcification (44?±?15?mmHg, P?=?0.04). However, on multivariate linear regression analysis for predicting PP, the only significant factor retained was left ventricle end diastolic diameter.

Conclusion

PP was weakly associated with large vessel calcification and atherosclerosis in hemodialysis patients. The bulk of the effect on PP seems to be due to hypervolemia.  相似文献   
44.
Does sodium nitroprusside reduce lung injury under cardiopulmonary bypass?   总被引:4,自引:0,他引:4  
Objective: We hypothesized that direct pulmonary arterial infusion of sodium nitroprusside (SNP) would ameliorate lung injury under cardiopulmonary bypass. Methods: Experiments were performed on 12 adult mongrel dogs of both sexes weighing 20–28 kg. The animals were randomly divided into two groups of six animals each. All animals were subjected to total cardiopulmonary bypass (CPB) and moderate hypothermia (28°C core temperature). During total CPB, the aorta was clamped together with the pulmonary artery to prevent any antegrade flow to the lungs. After cardioplegic arrest for 120 min, the animals were rewarmed, weaned from CPB, and their condition stabilized for another 90 min. After the release of the aortic cross-clamp, the dogs received either a 5% glucose solution as a placebo (group I) or SNP (0.5 μg/kg per min) (group II), both infused into the pulmonary arterial line. The infusion was stopped after 60 min. To measure lung tissue malondialdehyde (MDA), water content and polymorphonuclear leukocytes count, lung tissue samples were taken before CPB and after weaning from CPB. In addition, alveolar-arterial oxygen difference (AaDO2) for tissue oxygenation was calculated by obtaining arterial blood gas samples. Results: Values of MDA before CPB of 42.0±5.3 nmol/g of tissue rose to 67.6±5.7 nmol/g of tissue after weaning from CPB in group I (P=0.028). In group II MDA values also increased from 43.1±4.3 to 52.4±5.7 nmol MDA/g of tissue after weaning from CPB (P=0.046). The MDA increase in group II after CPB was found to be significantly lower than that for group I (P=0.004). The wet-to-dry lung weight ratio in the sodium nitroprusside group was 5.1±0.2, significantly lower than in the control group (6.8±0.4), (P=0.01). AaDO2 increased significantly in group I (P=0.028). There was no statistically significant difference (P=0.065) between groups I and II. During histopathological examination it was observed that neutrophil counts in the lung parenchyma rose significantly after CPB in both groups. The increase in group I was significantly larger than that in group II (P<0.001). Conclusions: The results represented in our study indicate that pulmonary arterial infusion of sodium nitroprusside during reperfusion can reduce lung injury under cardiopulmonary bypass.  相似文献   
45.
Methods: Second primary cancers constitute approximately 9–10% of malignancies diagnosed in the United States. We aimed to show the risk and incidance of second primary tumor occuring associated to urologic tumors and show the distrubution of tumors in Tracia region. We retrospectively examined the patients' files with the diagnosis of malignant disease between the years 1985–2000. Hazard function analysis was performed to estimate the relative risk of secondary malignancy occuring. Age, sex and tumor number were examined to find out if they affect on mortality rate. Results: A total number of 25 MPMNs were diagnosed. In 52 percent of the cases the second primary neoplasm developed within six months. The relative risk of development of a second neoplasm is found as increasing 1.111 times per month. The incidence of secondary malignancy occuring in the patients with one tumor was found as 6.31%. Age (p < 0.001) and tumor number (p < 0.001) are found as statistically effective predictor on mortality rate where the sex is not. Conclusions: In the patients with a primary tumor not only the metastasis must be investigated but also second primary tumors should be taken in to consideration. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
46.

Objective

This study evaluates the effect of enteric-coated mycophenolate sodium (EC-MPS) on patient and graft survivals, the incidence of rejection episodes, and graft function among de novo and maintenance renal transplant recipients.

Patients and Methods

This open label, multicenter, prospective, post-marketing observational study of 470 renal transplantation patients at 23 centers in Turkey includes 331 de novo patients whose mean age was 29.6 ± 13.2 years and 139 maintenance patients of 34.0 ± 13.0 years. The latter subjects had EC-MPS substituted for mycophenolate mofetil or added to the immunosuppressive therapy. Patients were followed for 12 months to evaluate graft function and treatment failure.

Results

The most common primary disease requiring transplantation was glomerulonephritis (24.3%). De novo and maintenance groups were similar in terms of overall rejection rates and acute rejection incidence whereas chronic rejection was evident only among the latter cohort (P < 0.001). Time to an acute rejection episode was significantly longer among maintenance rather than de novo patients (220.8 versus 18.7 months; P = 0.015). Overall, 12 and 36 month survival rates were 91.6 ± 1.3% and 86.9% ± 0.3% among subjects experiencing acute rejection versus 99.7 ± 0.2% and 50.3% for those displaying chronic rejection. Among maintenance group no deterioration of renal function was observed after conversion from mycophenolate mofetil to EC-MPS. The incidences of leukopenia, new-onset anemia, or liver dysfunction were similar between de novo and maintenance patients. Gastrointestinal discomfort was more prevalent among the maintenance group, reaching a significant level at the fourth visit (P < 0.05). EC-MPS dose reduction was required in only 16.7% of patients at visit, it was more frequent among the de novo group (17.9 versus 13.8%).

Conclusion

EC-MPS was an effective adjunctive therapy for de novo as well as maintenance renal transplant recipients in the Turkish population due to a relatively low incidence of dose reductions necessitated by adverse events as well as with an increased likelihood of long-term graft survival.  相似文献   
47.
48.
Background  Cardiovascular complications are common in patients with end-stage renal disease (ESRD). We aimed to investigate left ventricular (LV) function and carotid intima-media thickness (cIMT) in children and adolescents with ESRD. Methods  This study included 38 ESRD patients (15 hemodialysis and 23 peritoneal dialysis) and 17 age- and sex-matched healthy subjects. Results  The ESRD patients had significantly lower mean mitral E/A ratio, and higher left ventricular mass index (LVMI) and cIMT than the control group. Compared with PD patients, HD patients had worse LV diastolic function. In stepwise linear regression analysis, LVMI (P = 0.043) and hemoglobin (P = 0.015) turned out to be independent variables for predicting diastolic dysfunction (reduced E/A ratio), and the only significant predictor of cIMT was indexed diastolic blood pressure (DBP) (P = 0.035). Conclusion  Cardiovascular structure and function abnormalities are also common in pediatric dialysis patients, as in adults. Furthermore our data indicated that hemodialysis was disadvantageous for preserving LV diastolic function as compared with peritoneal dialysis.  相似文献   
49.
BACKGROUND: The aims of this study were to compare erythrocyte antioxidant enzyme activities, lipid peroxidation, and nitric oxide levels (NO) in women with postmenopausal osteoporosis (PMO) and non-porotic postmenopausal healthy controls and to assess the relationship between bone mineral density and these oxidant/antioxidant parameters. Additionally, in vivo effects of three different anti-osteoporotic drugs, calcitonin, risedronate and raloxifene, on the erythrocyte oxidant-antioxidant status in women with PMO were also assessed. METHODS: Postmenopausal women aged 40-65 years and without previous diagnosis or treatment for osteoporosis and independent in activities of daily living were included. Bone mineral density was measured at the lumbar spine and proximal femur using DXA. Erythrocyte enzyme activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase (CAT), and lipid peroxidation end-product malondialdehyde (MDA) and nitrite/nitrate levels, by product of NO, were assessed. Fifty-nine women with PMO were included (mean age 56.7 years), 44 completed course of therapy and were analyzed. Twenty-two non-porotic healthy women (mean age 55.8 years) were included as controls. RESULTS: Patients had significantly lower CAT and GSH-Px enzyme activity and higher levels of MDA and NO than non-porotic healthy controls. Proximal femur BMD measurements significantly correlated with NO levels. QUALEFFO scores improved in different levels with these short-term treatments. In all treatment groups, erythrocyte MDA levels significantly decreased; moreover, risedronate reduced NO levels and raloxifene enhanced CAT enzyme activity. CONCLUSIONS: Oxidative stress plays an important role in the pathogenesis of PMO. Studied drugs had ultimate effects on reducing lipid peroxidation. Raloxifene also had potent effects in the enhancement of antioxidant defense system.  相似文献   
50.
ObjectiveThe aim of this study was to determine the epidemiologic characteristics of, and the treatments used for, recurrent herpes labialis (RHL) in health students.MethodsA cross-sectional study was conducted with the participation of 333 nursing and midwifery students. Data on the sociodemographic characteristics of the participants, their history of RHL, and the treatments were collected by means of a standard self-reported questionnaire form.ResultsThe point prevalence of RHL was 3.9%, the annual prevalence was 44.7%, and the lifetime prevalence was 52.5%. These prevalences were not related to the participants' place of residence, level of income, school, gender, marital status, or smoking status (p > 0.05). RHL was frequently seen on the right side of the lower lip (17.9%). One third of the students who experienced RHL stated that they had applied treatment to the lesion. However, only 20.1% stated that they had used antiviral therapy. Treatment was recommended by a physician for only 16.1% of the subjects.ConclusionsThe prevalence of RHL was high among the health students, who were considered to represent young adults. Although they were students in a school of health, they lacked knowledge about RHL.  相似文献   
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