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101.
Gender differences, either with the structural or through with hormones, dictate how the corresponding organ or organ system responses to physiological signals. Current study aims to investigate gender dependent differences in conduction related parameters of rat sciatic nerve. Compound action potentials (CAP) were recorded via suction electrode whereas the conduction velocity distributions (CVD) were performed using the method known as collision technique in the literature. Studied CAP parameters, namely conduction velocities (CV), area of the CAPs and time required to reach the maximum depolarization (TP) have been found significantly different for female and male rats. Detailed analyses have shown that sex dependent differences were more remarkable in the right leg responses of female and male rats. Additionally, CVDs indicate that the number of fibers having CVs between 5-30 m/s is much more in male right sciatic nerve trunk when compared to age matched female rats. The present study, for the first time clearly shows that shift in the contribution of nerve fibers to lower CVs is the main causal of the sex dependent differences seen in rat sciatic nerve fibers.  相似文献   
102.
In order to get early information on the functional state of smaller myelinated fibers this article investigated the applicability of conduction velocity distribution on compound action potential recorded in experimentally demyelinated frog sciatic nerve. Conduction velocity distribution histograms were estimated by using the mathematical model the authors enhanced. The results suggest that by using appropriate conduction velocity distribution model the diagnosis time in demyelinating neuropathy may be shortened at least three times as compared with conventional conduction velocity assessment. Therefore, it may be concluded that a well-defined model designed for the estimation of the conduction velocity distribution may be used as a diagnostic tool for the early phase of peripheral demyelinating neuropathies.  相似文献   
103.
Case report of a patient with osteopoikilosis   总被引:2,自引:0,他引:2  
Osteopoikilosis (OPK) is a benign osteosclerotic dysplasia of unknown origin, which is an inherited autosomal disorder. Males and females are equally affected. It is usually asymptomatic and may only be recognized on radiological examination. In this study we report a 33-year-old woman with fibromyalgia who suffers from back and leg pain and was diagnosed OPK by radiologically and review literature.  相似文献   
104.
Diffusion tensor MR imaging in pediatric head trauma   总被引:1,自引:0,他引:1  
PURPOSE: We propose to investigate the fractional anisotropy (FA) values in pediatric patients with closed head trauma and correlate them with the initial Glasgow Coma Scale (GCS). MATERIALS AND METHODS: A retrospective evaluation of 24 pediatric patients (15 men, 9 women; mean age, 13 years; range, 2-18 years) who underwent both unenhanced head computed tomography and cerebral magnetic resonance imaging (MRI), including the tensor diffusion sequence, within 30 days of the incident. Twenty-two atraumatic control patients (9 men, 13 women; mean age, 9 years; range, 4-17 years) were randomly selected from the records of the radiology department within the same period. Fractional anisotropy measurements were taken from each of 6 major white matter volumes. Data extracted from the record of each subject included GCS, initial head computed tomographic results, and length of hospital stay. Kruskal-Wallis and t tests were used for statistical evaluation. RESULTS: The mean acute score on the GCS was 9.7 +/- 5. Mean duration of hospitalization days was 8.7 +/- 10. Statistically significant differences in mean FA values between trauma and control subjects were noted in corpus callosum. Trauma patients with positive findings on MRI and with GCS less than 10 also had lower FA values than patients with GCS greater than 10 and patients who had normal MRI findings. There was a negative correlation between time to discharge and FA values. CONCLUSIONS: In pediatric head trauma, MRI diffusion FA measurements can show abnormalities despite normal-appearing brain MRI findings. Larger investigations are required to verify the stability of correlations.  相似文献   
105.
A macrophage culture model was used to investigate the erosion of gamma irradiated poly(trimethylene carbonate) (PTMC) films. When the PTMC films were incubated in the culture medium, but physically separated from the cells by a membrane, no erosion occurred. In contrast, when the J774A macrophages were directly cultured on PTMC films, they adhered to the films and were found to have eroded the polymer surface. Macrophages adhered to gamma irradiated poly(?-caprolactone) (PCL) controls as well, but to a lesser extent than to the PTMC films. In this case, no signs of erosion were observed. Human skin fibroblasts cultured on PTMC and PCL films as controls also adhered to the films but did not erode the surfaces. The effect of enzymes and reactive oxygen species that can be secreted by macrophages on the erosion process was assessed using aqueous solutions of cholesterol esterase, lipoprotein lipase, esterase, potassium superoxide, and hydrogen peroxide. The PTMC films eroded in aqueous enzyme solutions as well as in aqueous superoxide solutions. Cholesterol esterase and superoxide anion radicals seem to be most involved in the macrophage-mediated erosion of PTMC. This macrophage culture model is useful in assessing the influence of macrophages on the in vivo biodegradability of polymers and in elucidating the biodegradation mechanisms involved.  相似文献   
106.
Reconstruction of large bone defects is still a major problem. Tissue-engineering approaches have become a focus in regeneration of bone. In particular, critical-sized defects do not ossify spontaneously. The use of electrospinning is attracting increasing attention in the preparation of tissue-engineering scaffolds. Recently, acellular scaffolds carrying bioactive agents have been used as scaffolds in "in situ" tissue engineering for soft and hard tissue repair. Poly(epsilon-caprolactone) (PCL) with two different molecular weights were synthesized, and the blends of these two were electrospun into nonwoven membranes composed of nanofibers/micropores. To stimulate bone formation, an active drug, "simvastatin" was loaded either after the membranes were formed or during electrospinning. The matrices were then spiral-wound to produce scaffolds with 3D-structures having both macro- and microchannels. Eight-millimeter diameter critical size cranial defects were created in rats. Scaffolds with or without simvastatin were then implanted into these defects. Samples from the implant sites were removed after 1, 3, and 6 months postimplantation. Bone regeneration and tissue response were followed by X-ray microcomputed tomography and histological analysis. These in vivo results exhibited osseous tissue integration within the implant and mineralized bone restoration of the calvarium. Both microCT and histological data clearly demonstrated that the more successful results were observed with the "simvastatin-containing PCL scaffolds," in which simvastatin was incorporated into the PCL scaffolds during electrospinning. For these samples, bone mineralization was quite significant when compared with the other groups.  相似文献   
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The aim of this study was to evaluate the impact of enuresis nocturna on quality of life of the mothers. Mothers who have a child with monosymptomatic nocturnal enuresis (n = 28) and mothers who have a child without any health problems (n = 38) were enrolled in the study. Groups were in balance for background variables (child’s age, gender, and number of siblings; mother’s age, marital status, highest year of education completed, and occupation; presence of health insurance; and type of residence). Short-Form Health Survey (SF-36) Questionnaire, the Beck Depression Inventory (BDI), and Spielberg’s State-Trait Anxiety Inventory (STAI) were applied to all mothers. The mothers of children with enuresis had significantly lower quality-of-life scores in the SF-36 for the bodily pain (p = 0.015) and role emotional (p = 0.014) subscales. We observed significant difference between groups according to BDI; mean score was higher in mothers who have a child with enuresis nocturna (p = 0.017). There was no significant difference between groups according to the STAI. Significant differences according to bodily pain and role emotional subscales of SF-36, and the BDI scores, show that the mothers were negatively affected by having a child with monosymptomatic nocturnal enuresis.  相似文献   
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