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61.
The aim of this study was to examine the effect of iloprost in renal injury induced by abdominal aortic ischemia-reperfusion (IR) and how it can modulate the expression of adhesion molecules during this effect. Twenty-four Wistar-Albino rats were randomized into three groups (n=8) as follows: control (sham laparotomy), aortic IR (120 min ischemia and 120 min reperfusion), and aortic IR + iloprost (0.45 microg/kg/hr intravenous infusion during 120 min reperfusion). Blood and renal tissue samples were obtained for biochemical analysis. A histological evaluation with both hematoxylin-eosin staining and immunostaining was also done. Biochemical analyses showed that aortic IR significantly increased (p<0.05 vs. control) whereas iloprost significantly decreased (p<0.05 vs. aortic IR) plasma levels of malondialdehyde, P-selectin, intercellular adhesion molecule-1 (ICAM-I), and tissue levels of malondialdehyde and catalase. Histological evaluation with immunostaining showed that aortic IR significantly increased (p<0.05 vs. control) whereas iloprost significantly decreased (p<0.05 vs. aortic IR) the immunoreactivity of P-selectin, tumor necrosis factor-alpha, CD11b, CD18, and ICAM-1. Hematoxylin-eosin staining showed that iloprost also attenuated the morphological changes associated with aortic IR. The results of this study show that iloprost reduces renal injury induced by aortic IR in rats and downregulates expression of adhesion molecules at both the local and systemic levels after aortic IR during this protective effect.  相似文献   
62.
Gestational diabetes insipidus (GDI) is a rare disorder characterised by polyuria, polydypsia, and excessive thirst usually manifesting in the third trimester of pregnancy. The etiology is thought to depend on excessive vasopressinase activity, a placental enzyme that degrades arginine-vasopressin (AVP), but not 1-deamino-8-d-arginine vasopressin (dDAVP), which is a synthetic form. This is a transient syndrome and may be associated with acute fatty liver of pregnancy and preeclampsia. The use of dDAVP in symptomatic cases has been proven as a safe method for both the mother and the fetus during the pregnancy. We report a case of recurrent gestational diabetes insipidus in successive pregnancies, which responded to dDAVP and subsided after delivery. This report was presented at 8th European Congress of Endocrinology held in Goteborg, SWEDEN in 3–7 September 2005.  相似文献   
63.
OBJECTIVES: Paraoxonase-1 is a high-density lipoprotein-associated enzyme with three activities, which are paraoxonase, arylesterase and dyazoxonase. Paraoxonase-1 was shown to decrease in patients with cardiovascular diseases. We aimed to examine serum paraoxonase and arylesterase activities, and their relation with oxidative stress markers such as lipid hydroperoxide and total antioxidant status in patients with cardiac syndrome X. METHODS: Forty-one consecutive patients with cardiac syndrome X (CSX group), 33 consecutive patients without cardiac syndrome X (non-cardiac syndrome X group) and 20 healthy volunteers as control group were taken into the study. Serum paraoxonase and arylesterase activities were measured spectrophotometrically. Lipid hydroperoxide levels were measured by ferrous oxidation with xylenol orange assay. Total antioxidant status was determined using an automated measurement method. RESULTS: Basal paraoxonase, salt-stimulated paraoxonase and arylesterase activities were significantly lower in patients with cardiac syndrome X than those of the non-cardiac syndrome X and control groups (P<0.001, for both). Moreover, lipid hydroperoxide was found at high level, and total antioxidant status was found at low level in patients with cardiac syndrome X than control and non-cardiac syndrome X groups (P<0.001, for all). In patients with cardiac syndrome X, in multiple linear regression analysis, both paraoxonase and arylesterase activities were independently correlated with lipid hydroperoxide levels (P=0.001, P=0.003, respectively), and also arylesterase activity was independently correlated with magnitude of ST depression (P=0.002). CONCLUSION: Reduced paraoxonase and arylesterase activities and total antioxidant status levels and enhanced lipid hydroperoxide levels in patients with cardiac syndrome X might indicate increased oxidative stress that can play a role in pathogenesis of cardiac syndrome X.  相似文献   
64.
Association of serum uric acid level and coronary blood flow   总被引:1,自引:0,他引:1  
OBJECTIVES: Slow coronary flow (SCF) has long since been identified and endothelial dysfunction and atherosclerosis of the epicardial coronary arteries and microvasculature are reported to be associated with SCF. Serum uric acid is an independent biochemical marker of atherosclerosis, oxidative stress and endothelial dysfunction. Consequently, we aimed to investigate the association between coronary blood flow and serum uric acid level by means of thrombolysis in myocardial infarction frame count (TFC) and other laboratory parameters, in patients with SCF compared with control participants. METHODS: Sixty-four patients with SCF and 369 control participants with normal coronary flow were studied after quantifying coronary blood flow according to TFC. Serum uric acid levels were determined using commercially available assay kits. The association between TFC and serum uric acid level and other clinical and laboratory parameters were evaluated. RESULTS: Statistically significant differences were present between SCF and control groups with respect to serum uric acid, and hemoglobin levels, heart rate, cigarette smoking and sex (P<0.05 for all). The mean TFC was significantly correlated with serum uric acid, urea, creatinine, high-density lipoprotein-cholesterol and hemoglobin levels, platelet count, male gender, cigarette smoking, heart rate and systolic blood pressure (P<0.05 for all). Serum uric acid level (chi(2)=22.86, beta=0.54, P<0.001), heart rate (chi(2)=7.42, beta=-0.034, P=0.032) and cigarette smoking (chi(2)=12.343, beta=0.969, P=0.025) were independent predictors of SCF, whereas serum uric acid level was the only independent predictor of the mean TFC (beta=0.298, P<0.001). CONCLUSIONS: These findings have shown that serum uric acid level is significantly associated with coronary blood flow and that elevated uric acid might be an independent predictor for the presence of SCF.  相似文献   
65.
AIM: To investigate the role of second-look laparoscopy in patients with acute mesenteric ischemia (AMI).
METHODS: Between January 2000 and November 2005, 71 patients were operated for the treatment of AMI. The indications for a second-look were low flow state, bowel resection and anastomosis or mesenteric thromboembolectomy performed during the first operation. Regardless of the clinical course of patients, the second-look laparoscopic examination was performed 72 h post-operatively at the bed side in the ICU or operating room.
RESULTS: The average time of admission to the hospital after the initation of syrnptoms was 3 d (range, 5 h-9 d). In 14 patients, laparotomy was performed. In 11 patients, small and/or large bowel necrosis was detected and initial resection and anastomosis were conducted. A low flow state was observed in two patients and superior mesenteric artery thromboembolectomy with small bowel resection was performed in one patient. In 13 patients, a second-look laparoscopic examination revealed normal bowel viability, but in one patient, intestinal necrosis was detected. In two of the patients, a third operation was necessary to correct anastomotic leakage. The overall complication rate was 42.8%, and in-hospital mortality rate was 57.1% (n = 6).
CONCLUSION: Second-look laparoscopy is a minimally invasive, technically simple procedure that is performed for diagnostic as well as therapeutic purposes. The simplicity and ease of this method may encourage wider application to benefit more patients. However, the timing of a second-look procedure is unclear particularly in a patient with anastomosis.  相似文献   
66.
BACKGROUND/AIMS: Dieulafoy's lesions are uncommon sources of upper gastrointestinal tract bleeding. Endoscopists must be aware of these lesions when evaluating patients with upper gastrointestinal tract bleeding. METHODOLOGY: The aim of this study is to analyze the results of active bleeding or recurrently bleeding Dieulafoy's lesions treated either by endoscopic injection therapy (EIT) or endoscopic band ligation (EBL). Fifteen patients who had active bleeding due to Dieulafoy's lesions were evaluated retrospectively with respect to demographic properties, comorbidities, endoscopic therapy procedures, and the success rate of the procedure. RESULTS: The incidence of Dieulafoy's lesions was 4.5% in all cases of upper gastrointestinal tract bleeding. Among the 15 patients there were nine men and six women with a median age of 52 years (25-84 years). Eleven of these lesions were located in the stomach, two were in the duodenum, and two were in the distal esophagus. Eight patients were initially treated by EIT and seven patients had EBL therapy. There was no recurrent bleeding in any of the patients treated with EBL, but five patients (62.5%) treated with EIT bled again and were treated secondarily with EBL. Two of these patients required surgical intervention and one died on the 15th day of surgery due to myocardial infarction. No endoscopy-related complications were detected. CONCLUSIONS: Endoscopic methods should be the first choice in treating bleeding Dieulafoy's lesions. Both EIT and EBL are successful methods for achieving initial hemostasis. However, EIT therapy has a higher re-bleeding rate. EBL is a safe and effective method for the treatment of bleeding Dieulafoy's lesions.  相似文献   
67.
Thymic hyperplasia is a common phenomenon in both children and young adults after chemotherapy and may explain the finding of a mediastinal mass in patients with malignant lymphoma after complete remission. In the present study, we report 5 cases with malignant lymphoma presenting with a mediastinal mass on CT scan after completion of chemotherapy diagnosed as thymic hyperplasia by PET-CT imaging. We retrospectively analyzed 5 patients who presented with anterior mediastinal masses a median of 4 months (range 3–6) after achieving complete remission following successful treatment for malignant lymphoma. Three patients were diagnosed with Hodgkin’s lymphoma (HL) and the others with non-Hodgkin’s lymphoma (NHL). The median age of the patients was 23 (range of 18–47). PET-CT was performed on these patients to determine the characteristics of a mass which had been detected on CT. PET-CT was performed for all patients, and the thymic masses demonstrated only mild FDG uptake considered to be consistent with thymic hyperplasia. During a median of 24 months of follow-up, all patients were recurrence-free with a median survival of 15 months (range 10–26 months). It is important to be aware of the possibility of thymic hyperplasia after chemotherapy to avoid misdiagnosis or over-staging of disease, as well as unnecessary biopsies, especially when the presenting anterior mediastinal mass was originally located near the thymus on CT scan. Mild FDG PET uptake was sufficient for the diagnosis of benign disease in the cases in this study.  相似文献   
68.
Background The reduction in peritoneal fibrinolysis is believed to be the pathogenetic mechanism of adhesion formation. The general conclusion based on previous clinical and experimental studies is that laparoscopic procedures produce less adhesion formation. The association between this beneficial effect of laparoscopic cholecystectomy and peritoneal fibrinolytic changes is not clear. Therefore, the authors aimed to compare the effects of open and laparoscopic cholecystectomy on peritoneal fibrinolysis. For this purpose, fibrinolytic parameters in peritoneal fluid were investigated 24 h after laparoscopic and open cholecystectomies. Methods In a prospective clinical study, peritoneal fluid was sampled via a drain 24 h after laparoscopic (n = 10) and open (n = 9) cholecystectomies. Activities and concentrations of tissue plasminogen activator (tPA), plasminogen activator inhibitor type 1 (PAI-1), and tPA/PAI-1 complex were determined by enzyme-linked immunosorbent assay (ELISA) kits. Results In peritoneal fluids, tPA and tPA/PAI-1 complex concentrations were higher in the open cholecystectomy group (p = 0.009 and p < 0.001, respectively), but tPA activity and PAI-1 concentrations did not differ between the groups (p = 0.514 and p = 0.716, respectively). Conclusions Fibrinolytic changes in peritoneal fluid have several similarities in open and laparoscopic cholecystectomies with regard to tPA activity and PAI-1 levels. However, higher tPA levels after the open procedure probably are secondary to more intense tissue handling leading to mesothelial release of tPA.  相似文献   
69.
The objective of this study was to evaluate the intraobserver and interobserver agreements in tape measurements of the ankle and calf circumference with due emphasis on the 3 main reference points, the patella, the tibial tuberosity, and the medial malleolus. The leg circumference at 2 locations was measured in 66 patients in the mornings of 2 consecutive days by 6 observers. Finally, a blinded couple measured leg circumferences at a line created on calves with a ballpoint pen of 68 outpatients to calculate interobserver agreement for lined regions. Leg circumference measurement was accepted as correct when the difference was less than 0.6 cm in 2 occasions. Intraobserver and interobserver agreements were calculated as the percentage of correct measurements. Chi-square test was used to compare intraobserver and interobserver agreements for each reference point. At the calf region, intraobserver and interobserver agreements based on the tibial tuberosity (88% and 81%) were better than those of the patella (65% and 57%) and the medial malleolus (73% and 65%). On the other hand, at above the ankle region, the agreements (79% and 62%) were also better than those of the patella (60% and 43%) and nearly the same as those of the medial malleolus (86% and 65%). Finally, interobserver agreement of the measurements at the created line with ballpoint pen (96%) was better when compared to those of the tibial tuberosity (81%), the patella (57%), and medial malleolus (65%) (p = 0.005, p < 0.001, and p < 0.001, respectively). The results of this study suggest that the tibial tuberosity as a reference point for leg circumference measurement has better intraobserver and interobserver agreements than those of the patella and the medial malleoli.  相似文献   
70.
Pharmaceutical Chemistry Journal - The aim of this study was to develop a new simple and cost-effective spectrophotometric method to be used as an alternative to chromatography for the analysis of...  相似文献   
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