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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   
2.
Y M El?in  U Akbulut 《Biomaterials》1992,13(3):156-161
Glucose oxidase was immobilized into photographic gelatin hardened by chromium(III) sulphate. The enzyme-gelatin mixture was coated on polyester film strips which allowed easy and simple handling during assays. The effect of gelatin and cross-linker concentrations on water content and enzymatic activity was studied. The effect of pH during immobilization and that of incubation temperature on maximum activity were examined. Enzyme leakage tests were carried out during reuse number studies. Consecutive use of strips followed by washing and resting between uses were found to affect the reuse number. A maximum immobilization of 68% was reached under optimal conditions. Mechanical stability and leakage were found to be functions of gelatin and cross-linker concentrations. Photographic gelatin was found to have many capabilities with extraordinary characteristics as a carrier on immobilization.  相似文献   
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To compare the outcomes of flexible ureterorenoscopy (F-URS) and mini-percutaneous nephrolithotomy (mini-PNL) in the treatment of lower calyceal stones smaller than 2?cm. Patients who underwent F-URS and mini-PNL for the treatment of lower calyceal stones smaller than 2?cm between March 2009 and December 2014 were retrospectively evaluated. Ninety-four patients were divided into two groups by treatment modality: F-URS (Group 1: 63 patients) and mini-PNL (Group 2: 31 patients). All patients were preoperatively diagnosed with intravenous pyelography or computed tomography. Success rates for F-URS and mini-PNL at postoperative first month were 85.7% and 90.3%, respectively. Operation time, fluoroscopy time, and hospitalization time for F-URS and mini-PNL patients were 44.40?min, 2.9?min, 22.4?h, and 91.9?min, 6.4?min, and 63.8?h, respectively. All three parameters were significantly shorter among the F-URS group (p?0.001). Postoperative hemoglobin drop was significantly lower in F-URS group compared to?mini-PNL group (0.39?mg/dL vs. 1.15?mg/dL, p?=?0.001). A comparison of complications according to the Clavien classification demonstrated significant differences between the groups (p?=?0.001). More patients in the F-URS groups require antibiotics due to urinary tract infection, and more patients in the?mini-PNL group required ureteral double J catheter insertion under general anesthesia. Although both F-URS and?mini-PNL have similar success rates for the treatment of lower calyceal stones, F-URS appears to be more favorable due to shorter fluoroscopy and hospitalization times; and lower hemoglobin drops. Multicenter and studies using higher patient volumes are needed to confirm these findings.  相似文献   
6.
Background: Cytokines are essential mediators of immune response. Chronic renal failure patients suffer from chronic inflammation that results from factors such as impaired renal function, accumulation of uremic toxins and bio incompatibility of dialyzer membranes. These patients are also at increased risk of cardiovascular diseases. We have evaluated cytokines, adipocytokines and inflammatory markers in patients with chronic renal failure undergoing hemodialysis (HD) and continuous ambulatory peritoneal dialysis (CAPD).

Material and methods: We have determined serum tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), high-sensitivity C-reactive protein (hsCRP), leptin and ghrelin levels of chronic renal failure patients treated with either HD (n?=?20) or CAPD (n?=?20). TNF-α, IL-6, ghrelin and leptin measurements were performed by commercially available kits based on enzyme-linked immunosorbent assay (ELISA) method. hsCRP levels were determined by turbidimetric methods.

Results: Serum TNF-α and IL-6 levels of patients on HD were significantly higher than those of the ones on CAPD (p?<?0.05). Ghrelin, leptin and hsCRP concentrations were similar in both groups.

Conclusions: We can conclude that cytokine production is more obvious in HD process.  相似文献   
7.

Background

Polycystic ovary syndrome (PCOS) is related to metabolic syndrome, insulin resistance, and cardiovascular metabolic syndromes. This is particularly true for individuals with central and abdominal obesity because visceral abdominal adipose tissue (VAAT) and epicardial adipose tissue (EAT) produce a large number of proinflammatory and proatherogenic cytokines. The present study aimed to determine whether there are changes in VAAT and EAT levels which were considered as indirect predictors for subclinical atherosclerosis in lean patients with PCOS.

Methods

The clinical and demographic characteristics of 35 patients with PCOS and 38 healthy control subjects were recorded for the present study. Additionally, the serum levels of various biochemical parameters were measured and EAT levels were assessed using 2D-transthoracic echocardiography.

Results

There were no significant differences in mean age (p?=?0.056) or mean body mass index (BMI) (p?=?0.446) between the patient and control groups. However, the body fat percentage, waist-to-hip ratio, amount of abdominal subcutaneous adipose tissue, and VAAT thickness were higher in the PCOS patient group than in the control group. The amounts of EAT in the patient and control groups were similar (p?=?0.384). EAT was correlated with BMI, fat mass, waist circumference, and hip circumference but not with any biochemical metabolic parameters including the homeostasis model assessment of insulin resistance index or the levels of triglycerides, low-density lipoprotein cholesterol, and high-density lipoprotein (HDL) cholesterol. However, there was a small positive correlation between the amounts of VAAT and EAT. VAAT was directly correlated with body fat parameters such as BMI, fat mass, and abdominal subcutaneous adipose thickness and inversely correlated with the HDL cholesterol level.

Conclusions

The present study found that increased abdominal adipose tissue in patients with PCOS was associated with atherosclerosis. Additionally, EAT may aid in the determination of the risk of atherosclerosis in patients with PCOS because it is easily measured.
  相似文献   
8.
Hydatid disease is caused by infection with the metacestode stage of Echinococcus tapeworms of the family Taeniidae. The primary carriers are dogs and wolves, and humans are accidental hosts that do not contribute to the normal life cycle of this organism. The liver is the most commonly involved organ in the body by cystic echinococcosis (CE) secondary to infection with Echinococcus granulosus. Management options for CE should depend on the World Health Organization (WHO) diagnostic classification. Small (<5 cm) WHO stage CE1 and CE3a cysts may be primarily treated with benzimidazoles; the first-choice drug is albendazole. In some situations the combination of albendazole and praziquantel may be preferred. Chemotherapy with a benzimidazole or albendazole plus praziquantel is also used as adjunctive treatment to surgery and percutaneous treatment. Drug treatments have been the indispensable therapeutic modalities for cystic echinococcosis.Key words: Cystic echinococcosis, Drug treatment, Albendazole, Mebendazole, PraziquantelHydatid disease is caused by infection with the metacestode stage of Echinococcus tapeworms of the family Taeniidae. Four species of Echinococcus cause infection in humans: Echinococcus granulosus and Echinococcus alveolaris are the most common, causing cystic echinococcosis (CE) and alveolar echinococcosis, respectively. The primary carriers are dogs and wolves, and intermediate hosts are sheep, cattle, and deer, Humans are accidental hosts that do not contribute to the normal life cycle of this microorganism. Humans are infected by ingesting ova from soil or water contaminated by the feces of dogs. Hydatid cysts are common in societies where agriculture and raising animals are common, and hydatid disease continues to be a serious public health problem in many countries, including Turkey.16 The most common site is the liver, followed in frequency by lung, kidney, and spleen.7,8 The other, less common sites, such as the heart, pancreas, bone, brain, and muscles, are very rarely affected.811 The first step in the prevention of hydatid disease is basic hygiene and the second step involves the approach to treatment. No consensus exists regarding the optimal treatment, although medical treatment is effective against larval E granulosus. In this study, we aim to discuss the effectiveness of medical treatment in the management of hydatid disease  相似文献   
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We evaluated the short-term results of percutaneous excimer laser angioplasty in acute myocardial infarction. Of the 18 patients studied, 2 were female and 16 male with a mean age of 56.6 +/- 12.1 years. Thrombolysis in myocardial infarction grades 0, 1, and 2 flow was observed in 10, 5, and 3 cases, respectively, prior to the procedure. The degree of stenosis was 97.9% +/- 5.1%. The lesion was crossed with a laser catheter in all cases, using a mean number of 808 +/- 384 laser pulses. Type C dissection developed in only 1 case (6%). Except for this case, distal flow was grade 3 in all the patients. Following the procedure, ST segment resolution exceeding 70% was achieved in 14 cases (78%) within the first 90 minutes. The success rate of laser ablation was 94% (17 patients). Stent implantation was performed in all the cases. In conclusion, laser angioplasty is an effective and reliable treatment for acute myocardial infarction.  相似文献   
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