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71.
Effect of sildenafil on anxiety in the plus-maze test in mice   总被引:2,自引:0,他引:2  
Several studies have shown a role of nitric oxide/cyclic guanosine monophosphate signaling pathway in the regulation of anxiety. The effects of the phosphodiesterase (PDE) 5 inhibitors on anxiety are not fully understood. The aim of present study was to investigate the possible role of sildenafil, an inhibitor of cyclic GMP-specific phosphodiesterase, on anxiety in the plus-maze test in mice. Sildenafil at a dose of 0.5 mg/kg had no significant effect on the behavior in the plus-maze test but at doses of 1 and 3 mg/kg induced an anxiogenic effect. The combination of sildenafil (1 mg/kg, i.p.) and methylene blue (1 mg/kg, i.p.) abolished the anxiogenic-like effect of sildenafil. The combination of sildenafil (1 mg/kg, i.p.) and L-arginine (50 mg/kg, i.p.) decreased the percentage of time spent in open arms compared to saline-treated group. Diazepam at a dose of 2 mg/kg significantly increased the percentage of time spent in open arms (p < 0.05). Sildenafil at a dose of 3 mg/kg and the combination of L-arginine (50 mg/kg, i.p.) and sildenafil (1 mg/kg, i.p.) significantly decreased the locomotor activity (p < 0.05). These results suggest that a nitric oxide-cGMP pathway seems to play an important role in sildenafil-induced anxiogenic-like effect.  相似文献   
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Orbital roof fractures are uncommon, and traumatic intraorbital encephalocele formation is a very rare complication of this type of injury. We treated 43 pediatric patients with orbital roof fractures at our center over a 4-year period. The aim of this study was to retrospectively investigate conditions that may lead to intraorbital encephalocele formation in children with orbital roof fractures. Each case was reviewed, and the cause of injury, associated clinical and computerized tomography findings, the Glasgow Coma Scale score on admission, neurological status, other bodily injuries, hospitalization time and type and width of the orbital roof fracture were recorded. The findings in 6 patients who developed encephaloceles were compared to corresponding findings in the 37 patients who did not develop this complication. A total of 44 orbital roof fractures were diagnosed by axial and coronal computed tomography scanning. Six of the 43 children developed intraorbital encephaloceles in the first month after head trauma. In each of these cases, magnetic resonance imaging demonstrated the intraorbital cystic lesion in communication with the subarachnoid space. The width of each orbital roof fracture was measured on axial and coronal computed tomography slices and was confirmed by measurements during surgery. The width of the fractures in the encephalocele cases ranged from 2-4 mm. Duraplasty and orbitoplasty were performed in all the patients with encephalocele. Pediatric patients with orbital roof fractures that exhibit more than 2 mm diastasis and are associated with frontal cerebral contusion may be at greater risk for developing intraorbital encephalocele. All such cases should be monitored closely and investigated further with magnetic resonance imaging.  相似文献   
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Sakarya ME  Unal O  Ozbay B  Uzun K  Kati I  Ozen S  Etlik O 《Radiology》2003,228(2):589-592
The purpose of this study was to evaluate the feasibility of using an open-configuration magnetic resonance (MR) imaging system with MR fluoroscopic guidance to perform percutaneous transthoracic fine-needle aspiration biopsy in patients with lung masses. Percutaneous transthoracic aspiration biopsies were performed with MR fluoroscopic guidance in 14 patients. The masses were 2-7 cm in diameter (mean, 4.1 cm). The needle was positioned by using a free-hand technique with MR fluoroscopic guidance. The needle tip reached the target lesion, and biopsy was performed. Analysis of the biopsy specimens facilitated a specific diagnosis in all patients. Pneumothorax was noted in two patients (14%) with chronic obstructive pulmonary disease. Study results showed that the described MR fluoroscopy-guided transthoracic biopsy technique can be used safely and successfully for lung masses. MR fluoroscopy can be used to reach the target lesion easily and accurately.  相似文献   
75.
The present study was performed to investigate the effect of propofol on anxiety using the elevated plus-maze test. Groups of mice received propofol (20, 40, 60 mg/kg) or diazepam (2 mg/kg), caffeine (30 mg/kg), L-arginine (100 mg/kg), m-chlorophenylpiperazine (m-CPP, 2.5 mg/kg) and then were placed in an elevated plus-maze that was composed of two opposite closed arms and two opposite open arms. Propofol (20, 40, 60 mg/kg) and diazepam (2 mg/kg) significantly increased the percentage of time spent in the open arms compared to control. Caffeine (30 mg/kg) and m-CPP (2.5 mg/kg) decreased the percentage of time spent in the open arms and these effects were antagonized when propofol (40 mg/kg) was administered before the test. L-arginine (100 mg/kg) has also produced anxiogenic effect and this effect was not prevented by propofol. All drugs used in this study did not significantly change locomotor activity. These results suggest that propofol has anxiolytic effect in plus-maze test.  相似文献   
76.
Post-traumatic stress disorder (PTSD) has been associated with decreased neopterin levels. In the present study, we evaluated whether this low neopterin levels would normalize following pharmacotherapy with sertraline in PTSD. Fourteen patients with PTSD and 14 controls were enrolled in the study. A clinical evaluation and measurements of neopterin levels before and after sertraline treatment were performed. In addition, all patients were assessed with the Clinician Administered PTSD Scale (CAPS). The mean neopterin levels were significantly lower in the patient group than control group at baseline and were negatively correlated with the duration of illness, or severity of illness. Sertraline treatment decreased the symptoms of PTSD; however this was not accompanied by a significant increase in neopterin production. In conclusion, our results reveal that the failure for neopterin to normalize through symptom alleviation suggests that either neopterin may be a trait marker of the illness, or that more sustained treatment is necessary to elevate the neopterin production. Received: 30 September 2002 / Accepted: 12 December 2002 Correspondence to Dr. Murad Atmaca  相似文献   
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Gitelman's syndrome is a primary renal tubular hypokalemic metabolic alkalosis. Hypokalemia and hypomagnesemia can cause cardiac tissue excitability and conduction. Global ventricular mechanical function is directly related to the contractile properties of cardiac myocytes, which are largely dependent on the flow of ions such as potassium and magnesium. Here, we show that increased levels of potassium, in addition to magnesium, in a patient with Gitelman's syndrome significantly impacts the timing of ventricular wall motion and the pattern of ventricular strain and torsion. Two‐dimensional speckle tracking echocardiography was used for evaluation of the hypokalemic–hypomagnesemic period (first day) and third day after potassium chloride and magnesium replacement therapy. The transthoracic echocardiography showed that the percent ejection fraction was similar in hypokalemic–hypomagnesemic (63%) and normokalemic–normomagnesemic (after potassium and magnesium therapy, 67%) hearts. However, decreased left ventricular apical 4‐chamber peak systolic longitudinal strain, left ventricle global peak systolic strain, and global torsion values increased after potassium chloride and magnesium replacement therapy.  相似文献   
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