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S. Fehmi Katirciolu A. Tulga Ulus Zülfikar Saritas Sadi Kaplan Ufuk Tütün Ayen Aks?yek Nusret Apaydin Eser ?zgencil Bahattin Ko? 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2003,51(8):344-348
Objective: This study was planned to investigate if there is any difference in terms of the muscle force between the distal and proximal
segments of the latissimus dorsi muscle.Subjects and Methods: An implantable mock circulation system was placed around the latissimus dorsi muscle. The wrapping procedure around the
implantable mock circulation was performed by using two different latissimus dorsi muscle segments. In group 1, the very proximal
and in group 2, very distal part of the latissimus dorsi were wrapped. The main differences is the blood supply to the distal
part of the latissimus dorsi that was interrupted during dissection. During the stimulation period which lasted 120 minutes,
the pressure developed in this system and adenosine triphosphate (ATP) levels were measured.Results: The stimulation at 20 Hz did not result in any change in pressure and metabolic data. When it was switched to 43 and 85
Hz, ATP levels decreased with a resultant drop in pressure in group 2. However ATP levels were 15.9±2.2 μmol/gr and 14.8±2.5
μmol/gr in group 1, 12.0±1.4 μmol/gr and 6.1±1.2 μmol/gr in group 2 at 43 and 85 Hz respectively (p<0.05) at the end of the
90 minutes. The pressures at the same time interval were 89±11 and 102±7 mmHg in group 1, 61±7 and 65±8 mmHg in group 2 (p<0.05).Conclusion: In this study, we demonstrated that changes in the distal segment of the latissimus dorsi muscle affects its performance
in terms of metabolic and pressure changes during high frequency electrical stimulation at 43 and 85 Hz. 相似文献
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Umbilical cord and maternal blood leptin concentrations in intrauterine growth retardation. 总被引:2,自引:0,他引:2
Leyla Yildiz Bahattin Avci Metin Inge? 《Clinical chemistry and laboratory medicine》2002,40(11):1114-1117
Leptin, the ob gene product, plays an important role in the regulation of body fat mass and weight. In previous studies, it was demonstrated that leptin is detectable in human fetal cord blood as early as at 18 weeks of gestation and that serum leptin concentrations are significantly reduced in small gestational age newborns. In the present study, we investigated whether umbilical and maternal serum leptin concentrations correlate with intrauterine growth retardation (IUGR). In addition, we aimed to determine the relationships between leptin concentration in the maternal and cord blood. We studied 40 newborn infants (21 female and 19 male; gestational age, 38-42 weeks) and their mothers. Of the infants studied, 10 had IUGR. Serum leptin concentrations were measured by radioimmunoassay. All newborns had detectable leptin concentrations. Leptin concentrations were significantly lower in newborns with IUGR and in their mothers (n = 10; 3.53 +/- 1.42 ng/ml, 6.75 +/- 1.47 ng/ml, respectively) than in infants experiencing normal growth and their mothers (n = 30; 5.58 +/- 2.98 ng/ml, 9.85 +/- 6.50 ng/ml, respectively) (p < 0.01 for newborns, p < 0.05 for mothers). There was no significant correlation between umbilical leptin concentration and maternal leptin concentration (r = 0.229; p = 0.155) in all study groups but, significantly, a correlation was observed in the group with IUGR (r = 0.736; p = 0.015). There were no significant correlations between both umbilical and maternal leptin concentrations and parity, delivery type and gestational age. There was a correlation between umbilical leptin concentration and birth weight of newborns (r = 0.383; p = 0.015) but no correlation with body mass index (BMI) of the newborns (r = 0.034; p = 0.834). Maternal leptin concentrations correlated with maternal weight and BMI (r=0.606; p=0.000, r=0.535; p=0.000, respectively). There was no correlation between maternal leptin concentrations and birth weight of the newborns (r=0.179; p=0.269) and with BMI of the newborns (r = 0.146; p = 0.367). There was no gender difference in leptin concentrations in the newborns (n=21; 5.50 +/- 3.37 ng/ml, for females; n = 19; 4.58 +/- 1.98 ng/ml for males) (p = 0.296). In summary, we have shown that IUGR is associated with a decreased leptin concentration in newborns and their mothers. The association between umbilical serum leptin and birth weight in this and other studies suggests a pivotal role of fetal leptin in regulating fetal growth and development. 相似文献
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Erkan Parlak Sedef Ozdal Kuran Sel?uk Di?ibeyaz Bahattin Ci?ek Dilek O?uz Burhan Sahin 《The Turkish journal of gastroenterology》2004,15(3):144-148
BACKGROUND/AIMS: Dominant stricture of an extrahepatic bile duct is responsible for symptoms and an exacerbation of cholestasis in 15-20% of patients with primary sclerosing cholangitis. The aim of this study was to evaluate the efficacy and safety of endoscopic treatment in this selected patient group. METHODS: Retrospectively, we evaluated 16 patients who were treated endoscopically due to elevation of serum biochemical liver tests and symptoms which were attributable to dominant bile duct strictures during the period 1990 to 2003. Symptoms and biochemical liver tests were compared before and after treatment. RESULTS: Sixteen patients underwent a total of 58 therapeutic endoscopic retrograde cholangiopancreatographies (ERCP). Sixteen endoscopic sphincterotomies, 15 balloon dilatations, 6 bougie dilatations, 3 stone/sludge extractions and 8 stentings were performed. Endoscopic therapy was technically successful in all patients (100%). Biochemical liver tests were significantly improved when compared with pretreatment values (p<0.001). Patients have been followed-up without stents except for the patients who had cholangiocarcinoma and cirrhosis at the beginning. Procedure-related early complications occurred in 8.6% of therapeutic endoscopic biliary procedures. There was no mortality due to endoscopic treatment. Two patients whose stents were changed every two to three months had cholangitis due to stenting during 13 stent periods. Four patients whose stents were changed in seven to 10 days developed suppurative cholangitis (total 6 stent periods). CONCLUSIONS: Endoscopic therapy of symptomatic dominant strictures in primary sclerosing cholangitis is safe and effective. The cholangitis seen in long-term stenting seems to be solved by short-term stenting. 相似文献
90.
Assessment of aortic stiffness and ventricular diastolic functions in patients with Behçet’s disease
Background: Behçets disease is a systemic vasculitis in which studies have given conflicting results about ventricular diastolic functions. However, tissue Doppler echocardiography has never been used in any of these studies. Aortic stiffness, a cardiovascular risk factor, may also precede ventricular dysfunction. Objectives: The aim of this study was to assess aortic stiffness and biventricular diastolic functions in patients with Behçets disease. Methods: A total of 26 patients with Behçets disease (mean age; 33±10 years) and 20 age- and sex-matched controls (mean age; 33±7 years) were included. Aortic stiffness was evaluated by aortic strain and distensibility. Ventricular diastolic functions were evaluated with both conventional and tissue Doppler echocardiography. Mitral E and A wave, E/A ratio of E wave, deceleration time, and isovolumic relaxation time were calculated. Results: There was no significant difference in diastolic Doppler parameters between patients and controls. Similarly, there was no significant difference in mitral annular E and A velocities between these two groups. Aortic strain in patients with Behçets disease was found to be significantly less than in the controls (8.3±4.9% and 15.7±2.7% respectively, p<0.001). Aortic distensibility was also significantly low in patients with Behçets disease when compared to controls (0.45±0.28 and 0.78±0.13 respectively, p<0.001). Beta index values were significantly high in Behçets patients (7.23±5.93 and 2.69±0.55 respectively, p<0.001). Conclusion: No significant diastolic dysfunction was found in left and right ventricles in patients with Behçets disease by using both conventional and tissue Doppler echocardiography. However, an increase in aortic stiffness was found, suggesting an inflammatory involvement of proximal aorta. 相似文献