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1.

Background

There is a need for a peripheral nerve model on which surgeons-in-training can simulate the repair of nerve injuries at their own pace. Although practicing on animal models/cadavers is considered the “gold standard” of microsurgical training, the proposed model aims to provide a platform for improving the technical skills of surgical trainees prior to their practice on cadaver/animal models. In addition, this model has the potential to serve as a standardized test medium for assessing the skill sets of surgeons.

Methods

Several formulations of silicone were utilized for the design and fabrication of a model which realizes the hierarchical structure of peripheral nerves. The mechanical properties were characterized via the Universal Testing Machine; the damage caused by the needle on the entry sites was assessed through scanning electron microscopy (SEM).

Results

Mechanical properties of the formulations of silicone were tested to mimic human peripheral nerves. A formulation with 83.3?wt% silicone oil and 0.1?wt% cotton fiber was chosen to be used as nerve fascicles. Both 83.3?wt% silicone oil with cotton fiber and 66.6?wt% silicone oil without fiber provided a microsuturing response similar to that of epineurium at a wall thickness of 1?mm. SEM also confirmed that the entry of the needle did not introduce significant holes at the microsuturing sites.

Conclusions

The proposed peripheral nerve model mimicked human tissues mechanically and cosmetically, and a simulation of the repair of a fifth-degree nerve injury was achieved.  相似文献   
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This study aimed to determine the effect of acute brucellosis on the auditory system. Forty-two patients with acute brucellosis were evaluated clinically, and with serological and audiological tests, before and after treatment. Hearing threshold averages were calculated at 11 different frequencies (250-8000 Hz) of the auditory airway, and statistical analysis was performed. The average hearing thresholds were > 20 dB, with standard audiometry at 6000-8000 Hz, and < 20 dB at all other frequencies. After treatment, the average auditory threshold decreased to < 20 dB at 6000-8000 Hz (p < 0.0001). Pure-tone hearing thresholds were improved at all frequencies after treatment, with statistically significant differences at all frequencies except 12,000, 14,000 and 16 000 Hz (p < 0.05). There was no permanent hearing loss caused by acute brucellosis, and hearing thresholds were restored after treatment. It was concluded that acute brucellosis affects the auditory system, especially at high frequencies, and that patients with all forms of brucellosis should be evaluated for hearing loss.  相似文献   
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A rare case of thymic carcinoma with multiple brain metastasis is reported. In our extensive review of the literature only six of 30 reports of intracranial thymoma metastasis describe multiple metastases. A 38-year-old man presented with signs of raised intracranial pressure that had began 15 days previously. Cranial MRI revealed over 70 cystic lesions in the supra and infratentorial regions. Stereotactic biopsy was planned. On the second day of his admission he deteriorated and died the following day. The autopsy revealed a mass in the mediastinum. In the brain parenchyma were multiple cystic lesions between 0.5 and 3 cm in diameter. Histopathologically they were diagnosed as metastases from the thymic carcinoma. The mean survival with a single brain metastasis is approximately 256 days, whereas with multiple brain metastases it is only 64 days, thus treatment of this tumor demands prompt surgery whenever possible and optimal adjuvant therapy.  相似文献   
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Brucellosis is a multisystemic disease that rarely leads to a fatal outcome. While reticuloendothelial system organs are mostly affected, peritonitis and posthepatitic cirrhosis are also complications of brucellosis, though they are very rare. Brucella spp. can also trigger immunological reactions. We report a case of brucellosis with peritonitis, renal failure and leucocytoclastic vasculitis caused by Brucella melitensis, which led to a fatal outcome. Brucellosis should be considered in the differential diagnosis of vasculitic diseases, especially in endemic areas.  相似文献   
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The aim of the present study was to compare the efficacy and the tolerability of three different antibiotic regimens for the treatment of acute otitis media in paediatric patients. 75 children, age range 6 months-6 years, divided into three groups, were involved in the study, each group consisting of 25 randomly assigned children (Group 1, amoxicillin 40 mg/kg tid per os for 10 days; Group 2, cefuroxime axetil 30 mg/kg bid per os for 10 days; ceftriaxone 50 mg/kg single-dose i.m.). No statistically significant difference was noted in the clinical efficacy among the different groups. Although amoxicillin is the drug of choice in paediatric otitis media, single dose ceftriaxone might be considered as an interesting alternative regimen when ease of administration and cost of therapy are considered.  相似文献   
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The initial response of liver cells to insulin is mediated through exocytosis of Cl channel-containing vesicles and a subsequent opening of plasma membrane Cl channels. Intracellular accumulation of fatty acids leads to profound defects in metabolism, and is closely associated with insulin resistance. It is not known whether the activity of Cl channels is altered in insulin resistance and by which mechanisms. We studied the effects of fatty acid accumulation on Cl channel opening in a model liver cell line. Overnight treatment with amiodarone increased the fat content by ∼2-fold, and the rates of gluconeogenesis by ∼5-fold. The ability of insulin to suppress gluconeogenesis was markedly reduced indicating that amiodarone treatment induces insulin resistance. Western blot analysis showed that these cells express the same number of insulin receptors as control cells. However, insulin failed to activate exocytosis and Cl channel opening. These inhibitory effects were mimicked in control cells by exposures to arachidonic acid (15 μ m ). Further studies demonstrated that fatty acids stimulate the PKC activity, and inhibition of PKC partially restored exocytosis and Cl channel opening in insulin-resistant cells. Accordingly, activation of PKC with PMA in control cells potently inhibited the insulin responses. These results suggest that stimulation of PKC activity in insulin resistance contributes to the inhibition of cellular responses to insulin in liver cells.  相似文献   
10.
In this study, we evaluated the role of the Prostate Imaging–Reporting and Data System (PI-RADS) classification of multiparametric magnetic resonance imaging (mpMRI) to determine the likelihood of prostate cancer (PCa) in patients with haemospermia. Fifty-one patients presenting with haemospermia between 2018 and 2020 were included in this retrospective study. Forty-two of the patients (82.4%) were over 40 years, and the median prostate-specific antigen (PSA) level was 1.4 ng/ml. Fourteen of the patients (27.5%) had recurrent haemospermia. All patients underwent mpMRI, and assessments were classified according to PI-RADS v2. The mpMRI revealed PI-RADS one to four lesions in 10 (19.6%), 30 (58.8%), 6 (11.8%) and 5 (9.8%) patients respectively. One patient with PI-RADS 3 and five with PI-RADS 4 lesions underwent cognitive fusion prostate biopsy depending on MRI findings, and two patients with PI-RADS 4 lesions were diagnosed with PCa. Patients with haemospermia and risk factors, that is aged over 40 years, a high PSA level or familial history of PCa, need a more thorough evaluation with mpMRI.  相似文献   
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