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The effects of methyl prednisolone (MPD), dimethyl sulphoxide (DMSO), and naloxone were examined in 38 albino rats after making an impact spinal cord injury on the midthoracic segments with a modified Allen’s weight dropping trauma method. Somatosensorial evoked potentials (SEPs) were recorded before and 12 h and 14 d after the injury from epidurally inserted electrodes on the parietal cortex with sciatic nerve stimulations. Lower extremity, motor functions of the animals were also examined. It may be concluded that in this study model, DMSO has a moderate effect which can be demonstrated clinically and through SEPs. Naloxone has no effect on the clinical outcome but causes reasonable improvement electro-physiologically.  相似文献   
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Plasma leptin levels in rats with pancreatitis   总被引:3,自引:0,他引:3  
Diagnosis of pancreatitis is based on the determination of serum amylase and lipase levels. However, recent identification of specific leptin receptors in the pancreas suggests that this peptide may also play some roles in the modulation of pancreatic function. The objective of the present study was to investigate the relationship between serum leptin levels and pancreatitis. Thirty male Wistar rats were divided into 3 groups: the control group, acute pancreatitis group and chronic pancreatitis group. Pancreatitis was induced by injection of ethyl alcohol into the common biliary duct. A sham laparotomy was performed in the control group. Control and acute pancreatitis groups were sacrificed 24 hours later, and chronic pancreatitis group was sacrificed on postoperative day 7. Blood was taken by cardiac puncture for the determination of plasma leptin levels, and the pancreatic tissue was excised for histopathologic confirmation of pancreatitis. Plasma leptin rose significantly from the median of 0.78 +/- 0.12 ng/ml in the control group to 1.92 +/- 0.10 ng/ml and 1.86 +/- 0.13 ng/ml in acute and chronic pancreatitis groups, respectively (p < 0.001, for both). There was no significant difference in the plasma leptin levels between the acute pancreatitis group and the chronic pancreatitis group (p > 0.05). These findings confirm that leptin has a role in pancreas inflammation, and the inflamed tissue can be the source of local production of leptin.  相似文献   
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Accumulation of oxidized proteins and impaired antioxidant system have been shown to be associated with arthritis. Serum sialic acid (SA) is known as a parameter of inflammation. In the present study, to explore the potential role of SA in arthritis, we measured serum SA levels, plasma protein oxidation, and antioxidant status in patients with primary osteoarthritis (POA) and inactive rheumatoid arthritis (RA). Inactive RA (iRA) was defined upon the American College of Rheumatology criteria for clinical remission of RA. A total of 40 patients (20 POA patients, including 4 male subjects, and 20 iRA female patients) and 20 healthy female subjects were included in this study. SA, antioxidants, and protein oxidation levels were determined spectrophotometrically in serum or plasma samples. Serum SA levels were significantly increased in POA (3.34 +/- 0.37 mM, p < 0.0001) and iRA (3.11 +/- 0.47 mM, p < 0.05), compared with healthy controls (2.41 +/- 0.16 mM). Plasma total antioxidant activity, plasma superoxide dismutase activity and serum reduced glutathione levels were significantly decreased in patients with POA and those with iRA, whereas plasma carbonyl content and serum total protein were increased in those patients. Moreover, plasma total thiol levels were significantly increased in iRA and decreased in POA. Thus, increased SA and protein oxidation levels are associated with the decreased antioxidant levels in POA and iRA patients. These results suggest that SA may be considered as a potent defense molecule against oxidative damage in arthritis. Antioxidant therapy may halt or ameliorate the progression of arthritis.  相似文献   
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Background: Atrial fibrillation is a frequent arrhythmia in patients undergoing hemodialysis. The consequences of hemodialysis on P wave durations and P wave dispersion have not been fully understood. The objective of this study was to study the effect of dialysis on P wave maximum (Pmax), P wave minimum (Pmin), and P wave dispersion (Pd). Methods: We studied Pmax, Pmin, and Pd in 32 patients (17 men and 15 women, mean age 54 ± 18 years) with chronic renal failure undergoing hemodialysis. The difference between maximum and minimum P wave duration was calculated and defined as P wave dispersion (Pd= Pmax? Pmin). Results: There was a significant increase in Pmax at the end of dialysis compared to the beginning (98 ± 13 ms vs. 125 ± 12 ms, P < 0.001). Pmin did not show any significant change (71 ± 11 ms vs. 73 ± 10 ms, P = 0.42). Pd was significantly increased at the end of dialysis (27 ± 9 ms vs. 52 ± 11 ms, P < 0.001). There was a negative correlation between serum potassium, magnesium, phosphate, blood urea nitrogen, and creatinin at the end of dialysis and Pmax and Pd, respectively (P < 0.05). A weak positive correlation was found between serum calcium, bicarbonate at the end of dialysis and Pmax and Pd (P < 0.05). Conclusion: Hemodialysis ends with significant increase in P wave maximum duration and P wave dispersion, which might be responsible for the increased occurrence of atrial fibrillation in these groups of patients.  相似文献   
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Background: The myocardial performance index (Tei index) is an echocardiographic index of combined systolic and diastolic functions. Brain natriuretic peptide (BNP) and its biologically inactive fragment N-terminal pro-BNP (NT-pro-BNP) are secreted by the heart in response to myocardial stretch. In this study, we investigated Tei index and NT-pro-BNP levels in patients with Wolff-Parkinson-White (WPW) syndrome before and after radiofrequency catheter ablation therapy (RFCA).
Methods: Thirty patients (19 males, 11 females, aged 35.5 ± 14.4 years) with WPW syndrome were enrolled in this study. Echocardiographic examination was performed before and 24 hours after RFCA. Tei index was calculated using Doppler echocardiography. Blood samples were taken before and 24 hours after RFCA to detect levels of NT-pro-BNP. Results: Although isovolumic contraction time (IVCT) and isovolumic relaxation time (IVRT) did not change, aortic ejection time (ET) was decreased after RFCA (276 ± 22 ms vs 254 ± 30 ms, P < 0.01). So Tei index was significantly higher in postablation period (0.36 ± 0.11 vs 0.42 ± 0.21, P < 0.05). NT-pro-BNP levels did not change significantly after RFCA. Conclusions: We demonstrated that restoration of normal atrioventricular conduction by RFCA, leads to increase in Tei index but does not effect plasma NT-pro-BNP levels .  相似文献   
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Long-term follow-up of pacemakers with an Autocapture pacing system   总被引:1,自引:0,他引:1  
The aim of this study was to evaluate the safety and performance of the Autocapture pacing system during a 5-year follow-up period. The study was conducted retrospectively between May 1996 and May 2001. Sixty consecutive patients who had undergone VVI pacemaker implantation using an Autocapture program with leads 1402T (n: 31) and 1452T (n: 29) were included in the study. Intraoperative measurements including a ventricular stimulation threshold test, sensing of intrinsic R wave (mV), and lead impedance (W) were done by a standard pacing system analyzer. Evoked responses (ER, mV) and polarization signals (PS, mV) were measured after the pocket was closed. Pacing thresholds by Autocapture (AC thrd, V) and Vario (Vario thrd, V), battery current (mA), and battery impedance (kW) were also repeated during predischarge and 1, 6, 12, 18, 24, 30, 40, 50, and 60 months after discharge. According to the ER and PS values an Autocapture algorithm could be activated in 49 patients (88%). The Autocapture algorithm remained active during the follow-up in all of these patients. In patients with inappropriate ER and PS values (11 patients, 12%), pacemakers were programmed to a VVIR pacing mode and Autocapture algorithm was inactivated. ER and PS values did not reach appropriate values to activate the Autocapture algorithm in any of these patients in consecutive follow-ups. Twenty-four-hour Holter monitoring could be conducted in 32 patients (53%). In all recordings, when the loss of capture occurred, it was confirmed that back-up pacing continued. When the first measurements recorded during implantation were compared to approximately the 5th year measurements; ER (9.2 mV vs 9.6 mV), PS signal (1.13 +/- 0.30 mV vs 1.15 +/- 0.72 mV), AC thrd (0.4 V vs 1.2 V), Vario thrd (0.7 V vs 1.3 V), and lead impedance (502 ohm vs 620 ohm) were not changed significantly. Battery impedance increased 1 kOhm between 30-40 months of the implantation. Seven deaths occurred during follow-up. Three patients had fatal myocardial infarction, one died due to a non-cardiac event, and the remaining three died due to progressive heart failure. Conclusion: ER, R wave amplitude, and PS, which are the main parameters for the continuation of Autocapture function, did not change significantly during long-term follow-up. High output back up pacing provided additional safety for sudden rises in threshold. The Autocapture pacing algorithm was found to be effective and reliable during long-term follow-up.  相似文献   
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AIM: In developed countries, there has been a recent increase in the prevalence of adenocarcinoma of the esophagus and cardia, along with a decrease in distal gastric cancers. Little is known regarding the prevalence of these diseases in developing countries. The aim of the present study was to evaluate changes in the prevalence of gastric adenocarcinomas in Turkey as a function of anatomic location. METHODS: Data were retrospectively collected from 16 centers from January 1990 to December 2000. Owing to the exclusion criteria, a total of 4065 cases of tumors of the stomach and distal esophagus were included. Tumors localized to the body, the antrum and pyloric channel were considered distal cancers. Helicobacter pylori (H. pylori) was also detected. RESULTS: Patients' mean age was 60.7 +/- 9 years, with a male : female ratio of 68:32. The ratio of distal/proximal adenocarcinoma was 2:1 for the western part of Turkey and 3:8 for the eastern part of the country (P < 0.0001), and this did not change during the 11 years. H. pylori was detected significantly less in the west compared to the east for distal tumors (65.7 vs 38.7%, respectively, P = 0.02). CONCLUSION: In Turkey, a developing country with a high H. pylori prevalence, contrary to the state of developed countries, the ratio of distal versus proximal gastric adenocarcinomas has not changed. Geographical distribution should be taken into the account in projecting the changing patterns of gastric cancers.  相似文献   
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AIM:To compare the effectiveness of argon plasma coagulation (APC) and heater probe coagulation (HPC) in non-variceal upper gastrointestinal bleeding.METHODS:Eighty-five (18 female,67 male) patients admitted for acute gastrointestinal bleeding due to gastric or duodenal ulcer were included in the study.Upper endoscopy was performed and HPC or APC were chosen randomly to stop the bleeding.Initial hemostasis and rebleeding rates were primary and secondary end-points of the study.RESULTS:Initial hemostasis was...  相似文献   
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