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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   
3.
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   
4.
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   
5.
Sympathetic skin responses from postauricular region in Meniere's disease.   总被引:10,自引:0,他引:10  
OBJECTIVE: To investigate the sympathetic nervous system activity in Meniere's disease (MD) by recording sympathetic skin responses (SSRs) from the postauricular region (PA). METHODS: Twenty-one patients with definite unilateral MD diagnosis and 12 healthy volunteers were studied by evoking right and left PA-SSRs with electrical stimulation of the left median nerve at the wrist in attack and interval periods of MD. Mean latencies and maximum amplitudes were used in statistical analyses. RESULTS: In unilateral definite MD patients, the mean latencies were longer and the maximum amplitudes were smaller on the involved ear side than those on the normal ear side (p<0.01 for both amplitude and latency) and than those from the controls (p<0.01 and p<0.05). In three patients, there was no detectable PA-SSR on the involved ear side while there were SSRs on the healthy side. In four patients, the responses were absent bilaterally during the attack period. CONCLUSIONS: There is a marked asymmetric sympathetic hypofunction in the area of the PA region of the involved ear in MD patients. SIGNIFICANCE: The PA region is a new site for recording sympathetic skin responses. PA-SSR is a useful tool to investigate sympathetic nervous system function in MD patients.  相似文献   
6.
An extracorporeal circulation technique was developed for use in rats to provide equilibrated blood samples for multiple hormone assays. The inclusion of the extracorporeal circulation did not significantly alter arterial blood pressure, cardiac output, heart rate or central venous pressure in either Brattleboro rats with hereditary diabetes insipidus (BDI) or normal rats of the parent Long Evans (LE) strain. Plasma adrenaline and noradrenaline levels did not alter in either BDI or LE rats following inclusion of the extracorporeal circulation but the vasopressin concentration rose significantly in the LE rats. The impaired recovery of the mean arterial blood pressure following haemorrhage in the BDI rats compared with normal LE animals was not further influenced by the inclusion of the extracorporeal circulation. Plasma vasopressin and adrenaline (but not nor-adrenaline) levels were significantly raised during, and after, haemorrhage in the LE rats while in the BDI rats only plasma adrenaline levels were significantly increased. These results show that the insertion of an extracorporeal circulation into an anaesthetized BDI or LE rat does not adversely affect the cardiovascular system despite the increase in baseline plasma vasopressin concentration in normal rats, and its subsequent removal provides an additional equilibrated blood sample for multiple hormone assay within the same animal. The increased release of both adrenaline and vasopressin (but not noradrenaline) after haemorrhage in the same animal is detected using this technique, and the importance of vasopressin to the normal recovery process confirmed.  相似文献   
7.

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   
8.
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   
9.
Infertility represents a major medical, economic, and psychological problem. Stem cells therapy for infertility has a great interest nowadays especially for cancer survivors at pre-reproductive and reproductive age.

 Thirty-two adult male albino rats were used, divided equally into four groups; Group I (Control group) received isotonic saline intraperitoneally (i.p.) as vehicle. Group II (Cisplatin-treated group) received Cisplatin (i.p.) at a single dose of 7 mg/kg, and then were sacrificed after 5 days. Group III (Stem-cell-treated group) received Cisplatin (i.p.) at a single dose of 7 mg/kg, then after 5 days received adipose-derived mesenchymal stem cells (ADMSCs) (1 × 106). Cells were injected in the rete testis, then after 60 days, the animals were sacrificed. Group IV (Auto healing group) received Cisplatin (i.p.) at a single dose of 7 mg/kg, and then left for 65 days then the animals were sacrificed. Cisplatin administration resulted in degenerative changes in the testicular architecture in the form of thickened irregular BM of seminiferous tubules. The germinal epithelium showed disorganization and marked reduction in the thickness, associated with Sertoli cells preservation. Features of apoptosis assured by elevated caspase-3 expression were noticed. The interstitium showed cellular infiltration and distorted Leydig cells. Injection of (ADMSCs) resulted in great improvement of testicular architecture and increase in the testosterone level associated with strong immune reaction of the CD-44. ADMSCs are recommended as a new treatment modality for male infertility.

Abbreviation: i.p.: intraperitoneally; BM: basement membrane; ADMSCs: adipose-derived mesenchymal stem cells; WHO: World Health Organization; MSCs: mesenchymal stem cells; DMEM: Dulbecco modified eagles media; PBS: phosphate-buffered saline; FACS: fluorescence-activated cell sorting; ELISA: enzyme-linked immunosorbent assay; CP: Cisplatin; ROS: reactive oxygen species; CAT: catalase; SOD: superoxide dismutase; OS: oxidative stress; SSCs: spermatogonia stem cells; GCs: germ cells; UCMSCs: umblical cord mesenchymal stem cells; TGFb1: transforming growth factor beta-1; BMP4: Bone morphogenic protein 4; BMP8b: bone morphogenic protein 8b.  相似文献   

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