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991.
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993.
BACKGROUND: There has been much evidence in recent years that free oxygen radicals and nitric oxide (NO) may play an important role in the pathophysiology of neuropsychiatric disorders. In this study, we aimed to investigate whether NO, xanthine oxidase (XO), superoxide dismutase (SOD), and adenosine deaminase (ADA) levels are associated with major depression (MD) and to evaluate the impact of antidepressant treatments on NO, SOD, ADA and XO levels in MD. METHODS: Thirty-six patients who were diagnosed as MD according to DSM-IV criteria and 20 healthy controls were included. The serum levels of NO, XO, SOD, and ADA were measured by spectrophotometric methods both in patients and controls. Patients were treated with antidepressant drugs for 8 weeks. All patients were assessed by Hamilton Depression Rating Scale (HDRS) both before and after antidepressant treatment. RESULTS: ADA and XO levels of the patients were significantly higher than the controls. SOD level of the patients was significantly lower than the controls. Although NO levels of the patients were higher than the controls, the difference was not statistically significant. There was no correlation between HDRS and the parameters studied (SOD, ADA, XO, and NO) of the patients. After 8 weeks of antidepressant treatment, ADA and SOD activities were increased, whereas NO and, XO levels decreased significantly. CONCLUSIONS: ADA, XO, and SOD activity may have a pathophysiological role in MD and may predict prognosis of MD. Activity of these enzymes may be used to monitor effects of the antidepressant treatment.  相似文献   
994.
BACKGROUND: The beneficial effects of avocado/soybean unsaponifiables (ASU) are known as an antiarthritic agent. This experimental study presents the effects of ASU on oxidant/antioxidant systems and the number of apoptotic neurons of hippocampal formation after ischemia and reperfusion. METHODS: Eighteen rats were divided into three equal groups: group I rats were used as controls; group II rats were fed with standard diet and group III rats were fed with standard diet plus ASU pills for 10 days. One day after electrocauterization of bilateral vertebral arteries for groups II and III, bilateral common carotid arteries were occluded for 30 min and then reperfused for 30 min. After these procedures, rats of all groups were sacrificed. The levels of malondialdehyde (MDA) and nitric oxide (NO) and activities of superoxide dismutase (SOD) and catalase (CAT) were measured in the left hippocampus. The number of apoptotic neurons was counted by Tunel method in histological samples of right hippocampus. RESULTS: MDA and NO levels increased in group II compared with group I rats (p = 0.002, p = 0.015). In group III, MDA and NO levels decreased as compared to group II (p = 0.041, p = 0.002). SOD and CAT activities increased in group III as compared to group II rats (p = 0.002, p = 0.002). The number of apoptotic neurons was lower in group III as compared to group II rats. CONCLUSIONS: The present findings suggest that ASU could decrease oxidative stress and apoptotic changes in ischemic rat hippocampus. Dietary supplementation of ASU may be beneficial to prevent or ameliorate ischemic cerebral vascular disease.  相似文献   
995.
The goal of this study was the development of a bioartificial nerve guide to induce axonal regeneration in the peripheral nervous system (PNS). In this in vitro study, the ability of a novel, 3-dimensional (3D), highly oriented, cross-linked porcine collagen scaffold to promote directed axonal growth has been studied. Collagen nerve guides with longitudinal guidance channels were manufactured using a series of chemical and mechanical treatments with a patented unidirectional freezing process, followed by freeze-drying (pore sizes 20-50 microm). Hemisected rat dorsal root ganglia (DRG) were positioned such that neural and non-neural elements could migrate into the collagen scaffold. After 21 days, S100-positive Schwann cells (SCs) migrated into the scaffold and aligned within the guidance channels in a columnar fashion, resembling "Bands of Büngner." Neurofilament-positive axons (mean length +/- SD 756 microm +/- 318 microm, maximum 1496 microm) from DRG neurons entered the scaffold where the growth within the guidance channels was closely associated with the oriented SCs. This study confirmed the importance of SCs in the regeneration process (neurotrophic theory). The alignment of SCs within the guidance channels supported directional axonal growth (contact guidance theory). The microstructural properties of the scaffold (open, porous, longitudinal pore channels) and the in vitro data after DRG loading (axonal regeneration along migrated and columnar-aligned SCs resembling "Band of Büngner") suggest that this novel oriented 3D collagen scaffold serves as a basis for future experimental regeneration studies in the PNS.  相似文献   
996.
In the operative treatment of humeral shaft fractures the radial nerve may be injured during the reduction of fracture fragments or the application of plate and screws. Also, secondary surgical explorations due to delayed or non-union carry a high risk of radial nerve injury because of the scarring of the neighboring tissue and proximity of the nerve to the implants. Consequently, the need for the transposition of the radial nerve to a safer position arises. A total of 22 (11 right, 11 left) cadaveric upper extremities were studied to evaluate the medial transposition of the radial nerve during the open reduction and anterolateral plate fixation of humeral fractures. The radial nerve was transposed medially in a distal plate fixated humeral fracture model. Distance measurements of the radial nerve and the division points of its branches were carried out in the transposed position and in the original course of the nerve. There was no statistically significant difference between the original course and medially transposed measurements. The distances from the reference point to the division points of other branches (posterior antebrachial cutaneous nerve, motor branch to brachioradialis, most distal motor branch to triceps) were not altered. The mean length of the radial nerve was 185.2 +/- 14.3 mm in its original course and 183.7 +/- 13.8 mm in the medially transposed course. In conclusion, the present study shows that medial transposition of the radial nerve through the fracture line does not increase the nerve's length and may be utilized in cases in which anterolateral plate fixation is indicated.  相似文献   
997.
OBJECTIVE: The purpose of this study was to investigate whether an inguinal hernia would have an impact on the testicular volume and blood flow by scrotal ultrasonography. METHODS: Twenty-six male patients with unilateral inguinal hernias with a mean age of 48.1 years were included in the study. Testicular volumes were calculated, and spectral parameters such as the pulsatility index and resistive index of the testicular artery at supratesticular, subcapsular, and intratesticular levels on both the side with the inguinal hernia and the contralateral side were measured by a preoperative ultrasonographic examination. Comparisons between the dependent groups were performed by a Wilcoxon or paired samples t test where appropriate. RESULTS: The mean +/- SD testicular volume on the side with the inguinal hernia was significantly higher than that on the contralateral testis (15.46+/-4.49 versus 14.54+/-3.65 mL, respectively; P<.05, Student t test). In addition, the mean resistive index of the intratesticular arteries was significantly higher on the side with the hernia compared with the contralateral side (0.66+/-0.06 versus 0.63+/-0.05; P<.05, Student t test). CONCLUSIONS: These data indicate that an inguinal hernia may impair testicular blood flow, which may be attributable to an intermittent mechanical compression effect on the funiculus spermaticus in the inguinal canal.  相似文献   
998.
999.
Dual left anterior descending artery (or dual anterior interventricular artery, LAD) is a rare coronary artery anomaly. Dual but normally originated LAD has been usually reported to have no clinical significance. In this case report, we present a case of 75 year old male with anginal symptoms in whom coronary arteriography showed normally originated dual LAD with two branches of almost equal caliber. The course of both branches were supplying the usual territory of LAD and both of the branches had significant proximal stenosis. The patient underwent a coronary artery bypass grafting operation and both branches were grafted. This normally originated dual LAD case may be considered to be interesting, because dual LAD branches were symmetrically involved with the atherosclerotic process in their proximal segments. In addition, this condition was demonstrated intraoperatively and the two branches were revascularized with bypass grafting.  相似文献   
1000.

Purpose

To investigate whether a novel method that combines breast imaging reporting and data system (BI-RADS) with strain elastography contributes to diagnostic performance in differentiation of malignant and benign breast lesions.

Methods

In 81 patients, 81 breast lesions were prospectively investigated. Breast lesions were separately evaluated with ultrasonography and strain elastography. While evaluations with ultrasonography were based on 2003 BI-RADS-US, strain elastography evaluations were based on a 5-point scale and strain ratio. Diagnostic performances of ultrasonography, strain elastography, and the combined method were compared.

Results

Among 81 lesions, 43 (53.1%) were benign and 38 (46.9%) were malignant. When a cutoff point of category 3 was used, sensitivity, specificity, positive and negative predictive values, and accuracy for BI-RADS were 100, 11.6, 50, 100, and 53%, respectively. When BI-RADS and strain ratio were combined, sensitivity, specificity, positive and negative predictive values, and accuracy were 89.5, 93, 91.9, 90.9, and 91.3%, respectively. When BI-RADS and elastography scores were combined, sensitivity, specificity, positive and negative predictive values, and accuracy were 86.8, 97.7, 97.1, 89.4, and 92.5%, respectively.

Conclusions

The combination of strain elastography and BI-RADS was found to have better diagnostic performances to diagnose breast lesions than BI-RADS alone.
  相似文献   
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