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BACKGROUND: Most duodenal injuries are managed with primary repair, but the degree of duodenal-wall injury may threaten the integrity of the primary repair. Therefore, we evaluated whether the primary repair site could be reinforced with histoacryl glue (HAG) or HAG with an expanded polytetrafluoroethylene (ePTFE) mesh. METHODS: Grade 3 duodenal injury in the second portion of the rat duodenum was chosen as a standard trauma model. Thirty-three male rats were divided into sham (n = 3), 2-layer primary repair (n = 10), 1-layer primary repair plus HAG application (n = 10) and ePTFE attached with HAG over the 1-layer primary repair site (n = 10) groups. Ten-day survival, adhesion grades and histological assessment were taken as outcome measures. RESULTS: A significant survival advantage was identified in the group that had an ePTFE graft attached with HAG over a 1-layer repair when compared with the group that had a 2-layer primary repair. Adhesion grades were found to be particularly increased in the group that had an ePTFE graft attached with HAG over the primary repair site, moderately increased in the primary repair plus HAG application group and lower in the 2-layer primary repair group. ePTFE graft application was found to be beneficial to coverage of the HAG-dependent empty spaces in the serosal layer. CONCLUSIONS: A primary repair site after duodenal trauma or a difficult duodenal stump can be reinforced with the application of HAG or ePTFE graft implantation with HAG.  相似文献   
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Factors leading to hydrocephalus after aneurysmal subarachnoid hemorrhage.   总被引:3,自引:0,他引:3  
Hydrocephalus is not a rare complication following aneurysmal subarachnoid hemorrhage. Hydrocephalus following subarachnoid hemorrhage can progress acutely (0-3 days), subacutely (4-13 days) or chronically (after 13 days). The predisposing factors leading to hydrocephalus after subarachnoid hemorrhage are not known exactly. This study assessed the predictive factors for the development of this condition. All patients presenting with subarachnoid hemorrhage between 1992-2001 were evaluated. All of them had initial computed tomography (CT) and hydrocephalus was diagnosed on CT scans. Age, gender, preexisting diabetes mellitus and hypertension, neurological state according to the Hunt and Hess scale at admission, Fischer grade on CT, the presence of intraventricular hemorrhage and localization of aneurysm were analyzed to see if there was any meaningful relationship between hydrocephalus and these factors. One hundred and fourteen patients with aneurysmal subarachnoid hemorrhage were evaluated. The incidence of hydrocephalus was 28.1 %. The incidence for acute hydrocephalus was 18.4 %, for subacute 5.2 % and for chronic 4.3 %. Sixty-nine percent of patients with hydrocephalus were graded as 3, 4 or 5 according to the Hunt and Hess scale on admission. Fifty-five percent of patients with hydrocephalus were graded as 3 and 4 according to Fisher grade on initial CT scan. Preexisting diabetes, higher Fisher grade and intraventricular hemorrhage were statistically significant predictors for the development of hydrocephalus. But only preexisting diabetes and higher Fisher grade were independent predictors according to multivariate analyses.  相似文献   
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Doppler ultrasound is known as a reliable technique, which demonstrates the flow characteristics and resistance of ophthalmic arteries. In this study, ophthalmic arterial Doppler signals were obtained from 106 subjects, 54 of whom suffered from ocular Behcet disease while the rest were healthy subjects. Multilayer perceptron neural network (MLPNN) employing delta-bar-delta training algorithm was used to detect the presence of ocular Behcet disease. Spectral analysis of the ophthalmic arterial Doppler signals was performed by least squares (LS) autoregressive (AR) method for determining the MLPNN inputs. The MLPNN was trained with training set, cross validated with cross validation set and tested with testing set. All these data sets were obtained from ophthalmic arteries of healthy subjects and subjects suffering from ocular Behcet disease. Performance indicators and statistical measures were used for evaluating the MLPNN. The correct classification rate was 96.43% for healthy subjects and 93.75% for unhealthy subjects suffering from ocular Behcet disease. The classification results showed that the MLPNN employing delta-bar-delta training algorithm was effective to detect the ophthalmic arterial Doppler signals with Behcet disease.  相似文献   
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We enrolled 386 subjects in a multicenter study of a point-of-care (POC) prothrombin time (PT) testing device. POC tests were performed by health care professionals using venous and finger-stick specimens and by patients using finger-stick specimens. Venous blood also was analyzed in the local hospital laboratory and a national reference laboratory. Accurate POC results were obtained by professionals using both types of specimens. Patients' results were equivalent to those of professionals. The identification of the patient's therapeutic status based on the International Normalized Ratio (INR) was equivalent for POC and local hospital laboratory PT results; 75% of local laboratory results and 77% of POC results were within 0.4 INR of reference laboratory results, while 93% of either system (POC or local laboratory) were within 0.7 INR. Patients overwhelmingly reported satisfaction with the self-test, including the finger stick and device operation. The INR from the POC device is clinically equivalent to the laboratory INR for assessment of anticoagulation status and management decisions in professional and self-testing environments. Patients can learn to perform accurate PT testing, and POC PT testing is feasible in patients' homes.  相似文献   
8.
狗颌面高速投射伤区小血管病理改变   总被引:1,自引:0,他引:1  
用光镜、电镜观察狗颌面高速投射伤区小血管的病理变化。实验发现:伤区小血管可见内皮细胞缺失、管壁断裂及细胞内的变性、坏死等病理变化,外径1.0~2,5mm的小血管损伤可远达距伤缘3.0cm处,该处血管7d后基本恢复。提示:临床运用血管化游离组织移植修复颌面部火器伤后的组织缺损时,其血管蒂应与距伤缘3.0cm以外的受区血管吻合,手术最好在伤后7d进行。  相似文献   
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The synthesis of full and semi interpenetrating networks (IPNs) based on poly(dimethy1-siloxane) (PDMS)/polystyrene, PDMS/polybutadiene and PDMS/poly(glycerylpropoxytriacry-late) 1
  • 1 Glycerylpropoxytriacrylate (GFTA):
  • is described. PDMS was used as host polymer in most cases. PDMS networks were prepared with two prepolymers having different number-average molecular weights between junctions, M?c = 15 · l03 and M?c = 75 · l03. Physical properties of IPN samples such as stress-strain behaviour, swelling and glass transition temperature (Tg) were examined. IPNs of both PDMS/polystyrene and PDMS/poly(glycerylpropoxytriacrylate) exhibit superior mechanical and elastomeric properties with respect to pure PDMS network. Most of the IPN systems studied in this work display two Tgs and indicate phase separation.  相似文献   
    10.
    颌面部狗咬伤的临床处理   总被引:3,自引:0,他引:3  
    目的 结合病例讨论颌面部狗咬伤后特点及临床处理。方法 本组19例,男18例,女1例;13岁以下17例。8天后就诊者给予抗感染及换药治疗,其余均行清创缝合,组织缺损者行拉拢缝合、全厚皮移植、皮瓣转移、唇颊及鼻沟组织瓣转移修复。常规注射破伤风抗毒素及狂犬疫苗。结果 8天后就诊者瘢痕愈合,2例轻度感染,其他均Ⅰ期愈合,无破伤风及狂犬病感染。结论 患者多为儿童,均为撕裂伤,就诊时要注意全身情况,彻底清创的同时,要尽可能保留组织;组织复位要准确,及时修复缺损,防止感染,减轻面部畸形。  相似文献   
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