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71.

Objective

To investigate the role of endogenous neuronal nitric oxide synthase (nNOS) on brain injury after burn and the effects of the captopril.

Methods

Wistar albino rats (200–250 g) were exposed on the dorsal surface to 90 °C (burn) or 25 °C (sham) water for 10 s. The ACE group was treated with intraperitoneal 10 mg/kg captopril immediately after burn and this treatment was repeated twice daily. At the end of the 24 h brain samples were taken. nNOS was studied in brain areas by immunohistochemistry.

Results

There was no difference between the cerebellar and hypothalamic areas the nNOS expression of all groups. nNOS expression increased in the frontal cortex, striatum and midbrain in the burn group compared to the control group. In the frontal cortex, nNOS expression significantly decreased after ACE inhibitor treatment (p < 0.05). The striatal nNOS of the ACE group significantly increased when compared to the control group (p = 0.001). In the midbrain of the animals, nNOS decreased in the ACE group. Hippocampal nNOS expression did not change after burn and significantly increased after ACE inhibitor therapy (p < 0.05).

Conclusions

Our data showed that the pathophysiological events following burn appear to be related to an acute inflammatory reaction which is associated with nNOS in the frontal cortex, striatum and midbrain, and captopril treatment abrogates the nNOS response in the frontal cortex and midbrain.  相似文献   
72.
Although closing force of cobalt alloy clip is well studied, there is only little information of titanium alloy clip available in the literature. In the present study, we examined and compared closing forces of various types and points of cerebral titanium and cobalt aneurysm clips for cerebral aneurysms. Straight, temporary, bayonet, angled, and fenestrated titanium or cobalt alloy clips were tested by measuring the closing forces at various points along their blade length. Closing forces of all the tested clips linearly increased from tip to base of clip blades. Sugita Titanium II clips had bigger closing forces than Elgiloy clips in all type clips except for the temporary clips. The closing forces of Sugita Titanium II and Yasargil titanium clips were similar in straight permanent type clip although there were some differences in closing forces between other types of Sugita and Yasargil clips. Our data showed that the closing forces differed depending not only on manufacturers but also on materials and shapes.  相似文献   
73.
74.

Objective

We aimed to analyze the development of epilepsy in a patient group with periventricular leukomalacia followed at a tertiary pediatric neurology center.

Patients and methods

The study included 108 children aged between 2 and 8 years with radiologically proven periventricular leukomalacia who had been regularly observed at the Istanbul University, Istanbul Faculty of Medicine, Department of Pediatrics, Pediatric Neurology outpatient clinic between January 2006 and December 2011.

Results

Neonatal seizures were reported in 22 patients (20.3%), 14 of whom developed epilepsy. A significant correlation was found between neonatal seizures and prematurity and newborn asphyxia (p = 0.013 and p = 0.010, respectively). Epilepsy developed in 35 patients (32.4%), history of neonatal seizures and more severe loss of white matter, periventricular hyperintensity and corpus callosum involvement were found to be correlated with epilepsy (p = 0.001, p = 0.004, p = 0.016, and p = 0.004, respectively). The most common seizure pattern observed was generalized tonic clonic seizures (n = 13) and complex partial seizures (n = 11). Those with focal EEG findings had a significantly better neurodevelopmental and cognitive level than those with multifocal/generalized EEG findings (p = 0.024). Seizures continued with varying frequency in 14 epileptic patients (40%) despite antiepileptic treatment.

Conclusion

Almost a third of patients with periventricular leukomalacia develop epilepsy that can be intractable in substantial part. Neonatal seizures and severe MRI findings are important clues that can indicate the development of epilepsy in these patients.  相似文献   
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76.
The aim of this investigation was to compare the traditional method of manual cephalometric tracing with four different computerized tracing programs, where the lateral cephalograms were scanned at 300 dpi and digitized onscreen. Thirty randomly selected cephalometric radiographs were used in this study. Four programs Dolphin Imaging, Vistadent, Nemoceph, and Quick Ceph were evaluated. Three dental, 11 skeletal, and 1 soft tissue parameters were measured that consisted of 5 linear and 10 angular measurements. Statistical analysis was carried out using multivariate analysis of variance and Box's and Levene's tests. No statistically significant difference was found between manual tracing and the computerized tracing programs. The measurements obtained with the cephalometric analysis programs used in the study were reliable.  相似文献   
77.
Carbon dioxide (CO2) is a greenhouse gas whose presence in the atmosphere significantly contributes to climate change. Developing sustainable, cost-effective pathways to convert CO2 into higher value chemicals is essential to curb its atmospheric presence. Electrochemical CO2 reduction to value-added chemicals using molecular catalysis currently attracts a lot of attention, since it provides an efficient and promising way to increase CO2 utilization. Introducing amino groups as substituents to molecular catalysts is a promising approach towards improving capture and reduction of CO2. This review explores recently developed state-of-the-art molecular catalysts with a focus on heterogeneous and homogeneous amine molecular catalysts for electroreduction of CO2. The relationship between the structural properties of the molecular catalysts and CO2 electroreduction will be highlighted in this review. We will also discuss recent advances in the heterogeneous field by examining different immobilization techniques and their relation with molecular structure and conductive effects.

Electroreduction of CO2 to CO using molecular catalysis.  相似文献   
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