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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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冠心病合并其他器质性心脏病的外科治疗   总被引:1,自引:0,他引:1  
目的分析冠心病合并其他器质性心脏病的临床特点,探讨一期外科治疗的方法和临床疗效。方法分析2004年4月至2006年4月冠心病合并其他器质性心脏病患者13例,其中风湿性心脏病联合瓣膜病1例,二尖瓣病变4例,二尖瓣退行性病变3例,主动脉瓣关闭不全3例,升主动脉瘤1例,继发孔房缺1例。因冠心病首诊入院5例,以其他器质性心脏病首诊入院8例。术前有心绞痛症状者8例,无心绞痛5例。体外循环下一期外科治疗。结果无死亡病例,13例均顺利出院。冠脉搭桥+瓣膜置换8例,冠脉搭桥+瓣膜成形3例,冠脉搭桥+Bentall+室壁瘤切除1例,冠脉搭桥+房缺修补1例。手术中搭桥1~3支,平均(1.92±0.73)支。术后1周,左心室舒张末内径(LVDD)为(51.77±2.64)mm,较术前[(58.92±3.81)mm]明显缩小(P<0.05)。随访3个月,心绞痛症状完全消失,心功能(NYHA)明显提高(P<0.05)。结论冠心病合并其他器质性心脏病临床症状无特异性,容易漏诊。虽然手术风险性和难度增加,但未得到血液重建,对患者更将是致命性的灾难,应争取一期手术。  相似文献   
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Introduction Iniencephaly, a neural tube defect involving occiput and inion and combined with rachischisis of the cervical, thoracic spine, and retroflexion position of the head is a very rare congenital abnormality of the fetus–newborn with a 0.1–10 of 10,000 prevalence. This abnormality’s prognosis is thought to be dismal. This abnormality can be associated with other abnormalities such as anencephaly, encephalocele, hydrocephalus, cyclopia, absence of the mandible, cleft lip and palate, cardiovascular disorders, diaphragmatic hernia, renal abnormalities, overgrowth of the arms compared to the legs, and club food and gastrointestinal atresia. Discussion Most of the patients are dead born, and the others die in a few hours. There are only six previously documented long-term survivors. In our case, our patient with iniencephalic signs and findings is still living. She is 2 years old now. We think that this patient presents a mild form of iniencephaly.  相似文献   
6.
The pathophysiology of akathisia still remains controversial. Iron deficiency was proposed to be an important factor in the development of akathisia. In the present study, it was aimed to compare levels of serum iron and linked variables in chronic akathisic (n=30), and non-akathisic patients (n=30) with schizophrenia and healthy controls (n=30) because of the controversy in the association of iron and akathisia. The Barnes Akathisia Scale for akathisia and Simpson-Angus Rating Scale for extrapyramidal side effects were used. Serum iron and linked variables and hematological profile of the patients and control subjects were determined. Serum iron levels were significantly lower both in akathisic and non-akathisic groups compared to the control group (P<0.001). Moreover, akathisic patients had significantly lower iron levels than non-akathisic patients (P<0.05). Total iron binding capacity was significantly higher in patients with akathisia compared to the control group (P<0.01). Although non-akathisic patients had a mild increase in total iron binding capacity, it was not statistically significant compared to the control group (P>0.05). Ferritin levels were determined to be significantly lower in both groups compared to the control group (P<0.01). In addition, there was a significant difference in ferritin levels between the patients with and without akathisia (P<0.05). In conclusion, our results support the hypothesis that an association between akathisia and iron metabolism exists.  相似文献   
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Fascioliasis is a worldwide zoonotic infection with fasciola hepatica and fasciola gigantica. The zoonoses are particularly endemic in sheep‐raising countries and are also endemic in Turkey. Clinical features of fascioliasis relate to the stage and intensity of infection. Fasciola hepatica infection comprises two stages: hepatic and biliary, with different signs and symptoms. Cholestatic symptoms may be sudden, but, in some cases, they may be preceded by a long period of fever, eosinophilia and vague gastrointestinal symptoms. We reported a case with fever and upper‐quadrant abdominal pain since 3 months that comes from an area endemic for fasciola hepatica, with suspected imaging about fasciola hepatica in common bile duct on ultrasonography. After that, fasciola hepatica was extracted with endoscopic retrograde cholangiography.  相似文献   
9.
BACKGROUND: Recipients of hearts from donors with spontaneous intracerebral hemorrhage (ICH) are at increased risk of allograft vasculopathy compared with trauma donors. We have recently shown that the vitronectin receptor (integrin alpha(V)beta3) is upregulated in transplant vasculopathy. We hypothesized that donor ICH is associated with systemic activation of alpha(V)beta3 in the donor before transplantation. METHODS: We evaluated mRNA expressions of alpha(V)beta3 (TaqMan PCR) in endomyocardial biopsy samples at 1-week post-transplant in 20 recipients from ICH donors and 20 recipients from trauma donors. To investigate whether systemic activation of alpha(V)beta3 was present in the donor before transplantation, alpha(V)beta3 expression was also evaluated in the corresponding donor spleen lymphocytes. All patients underwent serial coronary intravascular ultrasound to evaluate for coronary vasculopathy. The baseline characteristics were similar except for increased donor age in the ICH Group. RESULTS: The ICH Group showed significant increased mRNA expression of alpha(V)beta3 in the heart biopsy samples (3.8-fold, p = 0.012) and in the corresponding donor spleen lymphocytes (3.5-fold, p = 0.014) compared with the Trauma Group. At 1 year, the ICH Group also showed increased progression of coronary vasculopathy. Multivariate regression analysis found that donor lymphocytic alpha(V)beta3 mRNA expression was independently associated with increased risk of vasculopathy (odds ratio, 1.9; 95% CI, 1.21-3.98, p = 0.03). CONCLUSIONS: Our report demonstrates the presence of systemic activation of alpha(V)beta3 in donors with spontaneous intracerebral hemorrhage and its association with the subsequent development of allograft vasculopathy in the recipient.  相似文献   
10.
Epidemiologic evidence suggests that a full-term pregnancy may affect maternal risk of breast cancer later in life. The objective of this cross-sectional study was to compare circulating levels of maternal hormones affecting breast differentiation (human chorionic gonadotropin and prolactin) and proliferation [alpha-fetoprotein, insulin-like growth factor I (IGF-I), and estradiol] between women at a low to moderate risk (Asians and Hispanics), as compared with women at a high risk for breast cancer (Caucasians and African-Americans). Between May 2002 and December 2004, a total of 586 pregnant women were approached during a routine prenatal visit. Among them, 450 women (206 Caucasian, 126 Asian, 88 Hispanic, and 30 African-American) met the inclusion criteria and signed the informed consent. Only singleton pregnancies were considered. Blood samples were drawn during the second trimester of pregnancy. Laboratory analyses were done using the IMMULITE 2000 immunoassay system. Gestational age standardized mean levels of estradiol, IGF-I, and prolactin were significantly higher in Hispanic women compared with Caucasian women. Mean concentration of IGF-I was significantly higher in African-American women compared with Caucasian and Asian women. No significant differences in pregnancy hormone levels were observed between Caucasian and Asian (predominantly second-generation Chinese) women in this study. Irrespective of ethnicity, women who had their first pregnancy had substantially higher mean levels of alpha-fetoprotein, human chorionic gonadotropin, estradiol, and prolactin compared with women who previously had at least one full-term pregnancy. These data suggest that circulating pregnancy hormone levels may explain some of the ethnic differences in breast cancer risk.  相似文献   
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