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991.
Baykan M Erem C Gedikli O Hacihasanoglu A Erdogan T Kocak M Durmuş I Korkmaz L Celik S 《Endocrine》2007,31(3):300-304
Background Cushing’s Syndrome (CS) is associated with excess and premature cardiovascular disease. Endothelial dysfunction is the initiating
event in the development of atherosclerosis. Endothelial function is assessed by flow-mediated dilatation (FMD) of brachial
artery. The aim of this study was to assess FMD in patients with CS.
Methods We prospectively evaluated 22 patients with CS (12 women, 10 men; aged 42 ± 11 years, serum cortisol 28.2 ± 14 μg/dl, 24-h
urinary free cortisol (UFC) 269 ± 92 μg/day), and 23 control subjects (13 women, 10 men; aged 43 ± 10 years, serum cortisol
14 ± 4 μg/dl, 24 h cortisol 60 ± 22 μg/day). Endothelial function, measured as FMD of the brachial artery using ultrasound,
was calculated in two groups. Endothelial function was evaluated by assessing 1-min postischemic FMD of the brachial artery.
Results FMD was lower in patients with CS than that in those without (11.7 ± 4.8% vs. 15.8 ± 3.2%, P = 0.0001, respectively). There was no significant difference between two groups regarding baseline diameter of brachial artery.
But, hyperemia diameter was lower in patients with CS than without CS (3.6 ± 0.22 mm vs. 3.9 ± 0.19 mm, P = 0.04, respectively)
Conclusion Endothelium-dependent FMD may impair in patients with CS compared to controls. Measurement of endothelial function may identify
high-risk individuals early and therapy to reduce or retard endothelial dysfunction in patients with CS may lead to decreased
cardiovascular morbidity and mortality. 相似文献
992.
Tascilar O Cakmak GK Tekin IO Emre AU Ucan BH Bahadir B Acikgoz S Irkorucu O Karakaya K Balbaloglu H Kertis G Ankarali H Comert M 《World journal of gastroenterology : WJG》2007,13(46):6172-6182
AIM: TO investigate the effect of exogenous erythro- poietin (EPO) administration on acute lung injury (ALI) in an experimental model of sodium taurodeoxycholate- induced acute necrotizing pancreatitis (ANP). METHODS: Forty-seven male Wistar albino rats were randomly divided into 7 groups: sham group (n = 5), 3 ANP groups (n = 7 each) and 3 EPO groups (n = 7 each). ANP was induced by retrograde infusion of 5% sodium taurodeoxycholate into the common bile duct. Rats in EPO groups received 1000 U/kg intramuscular EPO immediately after induction of ANP. Rats in ANP groups were given 1 mL normal saline instead. All animals were sacrificed at postoperative 24 h, 48 h and 72 h. Serum arnilase, IL-2, IL-6 and lung tissue malondialdehyde (MDA) were measured. Pleural effusion volume and lung/body weight (LW/BW) ratios were calculated. Tissue levels of TNF-a, IL-2 and IL-6 were screened immunohistochemically. Additionally, ox-LDL accumulation was assessed with immune-fluorescent staining. Histopathological alterations in the lungs were also scored.RESULTS: The mean pleural effusion volume, calculated LW/BW ratio, serum IL-6 and lung tissue MDA levels were significantly lower in EPO groups than in ANP groups. No statistically significant difference was observed in either serum or tissue values of IL-2 among the groups. The level of tumor necrosis factor-(~ (TNF-(~) and IL-6 and accumulation of ox-LDL were evident in the lung tissues of ANP groups when compared to EPO groups, particularly at 72 h. Histopathological evaluation confirmed the improvement in lung injury parameters a~er exogenous EPO administration, particularly at 48 h and 72 h. CONCLUSION: EPO administration leads to a significant decrease in ALI parameters by inhibiting polymorphonuclear leukocyte (PMNL) accumulation, decreasing the levels of proinflammatory cytokines in circulation, preserving microvascular endothelial cell integrity and reducing oxidative stress-associated lipid peroxidation and therefore 相似文献
993.
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
994.
Karadeniz Cakmak G Emre AU Tascilar O Bektaş S Uçan BH Irkorucu O Karakaya K Ustundag Y Comert M 《World journal of gastroenterology : WJG》2007,13(7):1141-1143
Lipoma within an
inverted Meckel's diverticulum presenting with hemorrhage and partial intestinal
obstruction is an exceptional clinical entity.We report a case of 47-year-old male with a
history of recurrent episodes of partial intestinal obstruction and melena due to a
subserosal lipoma located in the base of an inverted Meckel's diverticulum.According to
our knowledge,this is the first case of a lipoma within a Meckel's diverticulum giving
rise to this clinical scenario without the existence of heterotrophic gastric or
pancreatic tissues. 相似文献
995.
Sargon MF Celik HH Aksit MD Karaağaoğlu E 《The International journal of neuroscience》2007,117(6):749-755
In this study, the myelinated axons of the rostrum, genu, truncus and splenium parts of the corpus callosum were counted in the human brain by using a camera lucida. The numerical densities of these axons were compared with each other by means of quantitative analytical statistical methods. The number of myelinated axons of genu and truncus of the corpus callosum were found to be highest in number and they were nearly the same with each other. However, number of the myelinated axons of splenium was found to be lower in number, when compared with the other parts of corpus callosum. 相似文献
996.
The aim of this study was to investigate possible correlations of the cognitive impairment with abnormalities of regional cerebral blood flow and electroencephalogram in children with (Down's Syndrome) DS. Nine patients with DS were evaluated by single photon emission computed tomography (SPECT) in combination with clinical findings, electroencephalography (EEG), and magnetic resonance imaging (MRI). In cases with IQs below 40, there were one or more findings of abnormal EEG/MRI and brain perfusion SPECT. In 6 cases (66.7%) EEG findings were normal, but 3 (33.3%) had abnormal EEG findings. Perfusion abnormalities were most pronounced in the fronto-parieto-temporal region in the form of hypoperfusion (n = 5) and in the right hemisphere (n = 5) than the left hemisphere (n = 1). These findings suggest that the children with DS had varying levels of structural, perfusion, and electrophysiological abnormalities in the brain and these abnormalities were reflected by measurable alterations of the cognitive functions. 相似文献
997.
BACKGROUND: Conventional methods in the diagnosis of carpal tunnel syndrome (CTS) in patients with polyneuropathy (PNP) are insufficient. AIMS: We suggest that the comparison of the conduction of the median nerve with that of the neighboring peripheral nerves may be more beneficial in the diagnosis of entrapment neuropathy. SETTING AND DESIGN: The median nerve sensory conduction in healthy volunteers, in cases of CTS, PNP cases without CTS and in cases of PNP in whom clinical findings point to CTS, were compared by palmar cutaneous nerve (PCN) sensory conduction. MATERIALS AND METHODS: Comparative parameters were difference of PCN-1st digits' nerve conduction velocities (NCV), PCN/1st digit NCVs ratio, difference of 5th-2nd digits' NCVs and 5th/2nd digits' NCVs ratio. STATISTICAL ANALYSIS: The statistical analysis was performed by the SPSS package for statistics. Student t test and receiver operating characteristic were used. RESULTS: Although the ratio of PCN-1st digit did not differ significantly between the control group and the polyneuropathy group, there was a significant difference between CTS and PNP+CTS groups and the control group ( P < 0.001 and P < 0.001, respectively). The ratio of PCN-1st digit nerve conduction velocity was also significantly different between polyneuropathy and PNP+CTS groups ( P < 0.001). CONCLUSION: To diagnose CTS on a background of polyneuropathy in mild cases in which sensory conduction is preserved, the ratio of sensory nerve conduction velocities of the palmar cutaneous nerve and the median nerve 1st digit-wrist segment may be a criterion. 相似文献
998.
The present study assessed the modulating effect of education level on cortisol reactivity to the Trier Social Stress Test (TSST) in a sample of 101 middle-aged adults (22 males, 79 females) between the ages of 50 and 65. The TSST involves a public speech and mental arithmetic task in front of an audience. No previous studies have assessed whether education level can have an impact on cortisol reactivity to this psychosocial stressor. It is plausible that greater exposure to academia may impact how one perceives and responds to the demands of the speech and arithmetic task. Should education have an impact on cortisol reactivity to the TSST, future studies will be required to control for this factor in order to reduce both statistical error and false interpretations. In addition to completing the TSST, participants were administered a battery of neurocognitive tests and personality questionnaires, including a report on education level (i.e. number of years total and degree: High School, Junior College, Technical, University). Results showed that adults with post-secondary education above Junior College tended to secrete higher cortisol levels overall, as measured by total area under the curve. However, it was the group with lower educational attainment who showed a greater stress response specific to the TSST, as measured by percentage increase in cortisol from pre- to post-TSST. Analyses also found that higher educated adults performed better than their less educated peers on verbal fluency. Considering that the TSST is an oral task, it is suggested that middle-aged individuals with a lower level of education may find the TSST more stressful due to lower verbal capacity, which may lead to an increased cortisol response to the TSST when compared to individuals with a higher level of education. 相似文献
999.
1000.
White T Kendi AT Lehéricy S Kendi M Karatekin C Guimaraes A Davenport N Schulz SC Lim KO 《Schizophrenia Research》2007,90(1-3):302-307
INTRODUCTION: One hypothesis that unifies the diversity of symptoms associated with schizophrenia involves the disruption of connectivity between brain regions. As white matter provides rapid and efficient communication between brain regions, this study was initiated to assess the early disruption of white matter pathways in children and adolescent with schizophrenia. MATERIALS AND METHODS: Diffusion tensor images were acquired on 14 children and adolescents with schizophrenia, one subject with schizoaffective disorder, and 15 age and gender matched controls. The DTI images were acquired in twelve directions on a 3 T Siemens Trio scanner. The images were transformed into fractional anisotropy and mean diffusivity maps and a group analysis was performed using SPM2. RESULTS: Children and adolescent patients with schizophrenia demonstrated a significant decrease in FA and associated increase in AD in the left posterior hippocampus (p<0.001, Bonferroni corrected on the cluster-level). These diffusion differences were not statistically significant when IQ was used as a covariate in the analysis. DISCUSSION: These findings suggest hippocampal white matter abnormalities that present early in the development of schizophrenia. The lack of significant differences when IQ is used as a covariate suggests that this hippocampal region is associated with cognitive changes associated with schizophrenia. 相似文献