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1.
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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BACKGROUND: Despite plenty of research, the cause of recurrent aphthous stomatitis (RAS) remains obscure. It has been proposed that, the aetiological factors such as local trauma, smoking, vitamin deficiencies and viral infections lead to aphthae formation via final common pathway based on increased oxidative stress. The aim of this investigation was to evaluate the antioxidant enzyme superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSHPx) alterations in plasma and saliva, and in addition uric acid (UA) in saliva, in patients with RAS and healthy controls. METHODS: Thirty-two patients with RAS and 30 healthy controls were included into the study. The SOD, CAT, GSHPx and UA levels were measured in plasma and saliva in study and control groups. RESULTS: In the RAS group, although the mean SOD (P<0.001) and CAT (P<0.05) levels of plasma were lower, GSHPx (P<0.001) levels were higher than control group. The salivary concentrations of the SOD (P<0.001), CAT (P<0.05) and GSHPx (P<0.001) in RAS group were entirely opposite to plasma concentrations. UA were not significant between RAS group and controls. CONCLUSION: Since we found salivary SOD and CAT levels were high whereas plasma levels were low, it has been thought that, salivary defence mechanisms via antioxidant agents may be stimulated against to the ulcerous lesion. We consider that the organism might mobilize the antioxidant potential to the sites where they were needed. At this point, decrease of SOD and CAT levels in the plasma may be related to this shift. It is also thought that GSHPx secretion in the saliva may also be increased but the increase in its turnover may be responsible for the diminished activity.  相似文献   
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Summary The excretion of thioethers was determined in the urine of workers involved in road paving operations and in the preparation of asphalt mixing in an asphalt plant. An occupationally nonexposed group served as control. From the results it was observed that there was no significant difference in urinary thioether levels between the exposed and nonexposed groups, however, smokers of both exposed groups had significantly higher urinary thioether levels than the nonexposed smoking workers. These results suggested that higher urinary thioether excretion could be only due to a difference in smoking behaviour. There were also significant differences in urinary thioether levels between the exposed smoking and nonsmoking workers. The authors suggest that these workers have a low mutagenic/carcinogenic risk and smoking is responsible for the majority of thioether excretion, as has been found by other investigators.  相似文献   
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Purpose. The interaction of salmon calcitonin (sCT) and poly (d,l-lactide-co-glycolide) was detected during preparation and evaluation of microspheres. The purpose of this study was to quantitate the extent and nature of the interaction. Methods. Blank microspheres were prepared by an aqueous emulsification solvent extraction technique. Adsorption studies were carried out at six concentrations of sCT and three concentrations of microspheres. Adsorption isotherms were constructed using the Langmuir and Freundlich treatments. Results. Adsorption at 1 mg/ml sCT concentration resulted in almost complete depletion of the peptide from the adsorption medium with the time to reach maximum adsorption decreasing with increasing microsphere concentration. At sCT concentrations below 100 µg/ml, a true equilibrium occurred in 1 hour or less while at higher concentrations (up to 350 µg/ml), a transient equilibrium was reached in 1 to 2 hours, followed by further adsorption of the peptide. The adsorption followed the Langmuir isotherm at concentrations below 200 µg/ml, indicating formation of a monolayer. Multilayer interaction, described by the Freundlich isotherm, occurred at higher concentrations and resulted in complete depletion of sCT from the adsorption medium. The affinity constant during monolayer formation was 0.09 and the plateau surface concentration was 5.1 µg/mg. The multilayer peptide-peptide adsorption showed a lower affinity (0.025) but higher capacity (24 µg/mg) than the monolayer peptide-polymer adsorption. Conclusions. The results show that poly (d,l-lactide-co-glycolide) microspheres have a high adsorption capacity for sCT which must be considered in formulating a controlled delivery product of this peptide.  相似文献   
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Background  

The objective of this study is to investigate the perceptions of first and third year medical students on self-study and reporting processes of Problem-based Learning (PBL) sessions and their usage of learning resources.  相似文献   
7.
Abstract: Achalasia is a motor disorder of the esophagus resulting in functional obstruction. The cause of the lesion is unknown although genetic and immunologic factors have been suggested. An association with serological HLA epitopes has been previously reported. In this study, we have further examined this HLA class II association with susceptibility to achalasia by DNA based methods. Achalasia patients ( n =40) and healthy controls ( n = 275), all Caucasians and unrelated, were included in the analysis. The strongest associations were with HLA-DQAl*0101 and two HLA-DQαβ heterodimers having their a chain encoded by this allele. Moreover, relative risk was significantly higher in DQAl*0101 homozygotes as compared to heterozygotes and results suggested that DQB1*02 may have a protective role.  相似文献   
8.
Interactions between the CXCR4 chemokine receptor in breast cancer cells and the ligand CXCL12/SDF-1α are thought to play an important role in breast cancer metastases. In this pilot study, CXCR4 expression along with other biomarkers including HER2-neu and EGFR, were measured in primary tumor samples of patients with operable breast cancer to test whether any of these biomarkers alone and in combination could indicate breast cancer with high likelihood of metastasizing to bone marrow. Cytokeratin (CK) positive cells in bone marrow were identified by flow-cytometry following enrichment with CK 7/8 antibody-coupled magnetic beads. Primary tumors (n = 18) were stained with specific antibodies for CXCR4, HER2-neu, EGFR, and PCNA using an indirect avidin–biotin horseradish peroxidase method. The majority of the patients had T2/T3 tumors (72%), or lymph node involvement (67%) as pathologic characteristics that were more indicative of high-risk breast cancer. High CXCR4 cytoplasmic expression was found in 7 of 18 patients (39%), whereas 6 of 18 patients (33%) were found to have CK positivity in bone marrow. The median number of CK+ cells was 236 (range, 20–847) per 5 × 104 enriched BM cells. The presence of CK+ cells in bone marrow was found to be associated with increased expression of CXCR4 alone or in addition to EGFR and/or HER2-neu expression (P = 0.013, P = 0.005, and P = 0.025, respectively) in primary tumors. Furthermore, three patients with high CK positivity (>236 CK+ per 5 × 104 enriched bone marrow cells) in bone marrow exclusively expressed high levels of CXCR4 with EGFR/HER2-neu (P = 0.001). Our data suggest that high CXCR4 expression in breast cancer may be a potential marker in predicting isolated tumor cells in bone marrow. CXCR4 coexpression with EGFR/HER2-neu might further predict a particular subset of patients with high CK positivity in bone marrow.  相似文献   
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