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31.
Anaerobic Treatability of Wastewater Contaminated with Propylene Glycol   总被引:1,自引:0,他引:1  
The purpose of this study was to investigate the biodegradability of propylene glycol in anaerobic conditions by using methanogenic culture. A master reactor was set up to develop a culture that would be acclimated to propylene glycol. After reaching steady-state, culture was transferred to serum bottles. Three reactors with same initial conditions were run for consistency. Propylene glycol was completely biodegradable under anaerobic methanogenic conditions. Semi-continuous reactors operated at a temperature of 35°C had consistently achieved a propylene glycol removal of higher than 95 % based on chemical oxygen demand (COD). It was found that in semi-continuous reactors, anaerobic treatment of propylene glycol at concentrations higher than 1,500 mg COD m?3 day?1 was not convenient due to instable effluent COD.  相似文献   
32.
Inappropriate treatment of axillary burns frequently results in adduction contractures. In this clinical study we have reviewed 32 patients with different types of axillary post-burn adduction contractures.We have used a variety of surgical treatments for reconstruction of axillary contracture releasing defects such as simple grafting, Z-plasties and locally pedicled flaps. Among these alternatives, we preferred to use scapular island flap most frequently. In addition to conventional harvest of this flap, extension of its pedicle up to the subscapular ramification by passing it through the triangular space allowed its transfer even to the anterior axillary line defects in a vertical orientation without pedicle kinking.In conclusion, the island scapular flap is a good choice for reconstruction of all types of axillary contracture, releasing defects with satisfactory results in terms of function and cosmesis.  相似文献   
33.
BACKGROUND: Reduced salivary flow has been reported in patients undergoing hemodialysis (HD) treatment. Our aim was to investigate the most important factors associated with stimulated salivary flow rate (ssfr) in chronic HD patients. METHODS: Fifty HD patients (27 F, 23 M, mean age 46. 7 +/- 13.2 years) were divided into two groups according to the duration of HD treatment as those receiving HD therapy less than or equal to (group I) or those more than (group II) 24 months. Fasting blood samples were obtained to determine hepatitis B and C serology, and biochemical and hematological parameters before a HD session. After prestimulation with a standard weight paraffin wax, stimulated saliva was collected in the HD patients and control group (23 F, 25 M, mean age 45.7 +/- 19.1 years) and the flow rate was expressed as ml/min. RESULTS: Both HD groups consisted of 25 patients. There was no significant difference between the two HD groups other than serum alkaline phosphatase (ALP) levels and presence of HCV. The ssfr was decreased than controls in both groups (0.8 +/- 0.6 and 0.7 +/- 0.4, respectively, vs. 1.5 +/- 0.5 ml/min) and it did not correlate with any parameter. Smoking had a positive effect on ssfr in all groups. CONCLUSION: Although the salivary flow rate decreased significantly in chronic HD patients, the duration of therapy displayed no effect on the salivary changes in HD patients, but smoking increased ssfr.  相似文献   
34.
BACKGROUND/AIMS: Circulating CD14+CD16+ monocytes, a potent phagocytosing and antigen-presenting monocyte population, have been reported to be expanded in patients on hemodialysis (HD). In this study, changes in the population of CD14+CD16+ monocytes were analyzed during a single session of HD therapy, and the influence of dialyzer membrane materials on these monocytes was investigated. METHODS: Nine patients were hemodialyzed using regenerated cellulose (RC) membranes and thereafter polysulfone (PS) membranes. Peripheral blood cells were taken from these subjects, and these cells were stained with anti-CD14 and anti-CD16 antibodies. The percentages of CD14- and CD16-expressing monocytes were analyzed by two-color flow cytometric analysis. Moreover, the serum soluble CD14 (sCD14) levels were measured with an ELISA kit. RESULTS: It was found that CD14+CD16+ monocytes before HD were significantly increased in patients on HD as compared to healthy controls. In the RC group, CD14+CD16+ monocytes were decreased at both 30 and 240 min after the initiation of HD. The reduction rate of CD14+CD16+ monocytes in the RC group was higher than that in the PS group. There was no significant difference in sCD14 levels between the two groups. CONCLUSION: Monocytes are activated in patients on HD. Furthermore, the population of CD14+CD16+ monocytes was stimulated to a greater extent during HD in the RC group than in the PS group. The significant reduction in CD14+CD16+ monocytes by RC membranes indicated that the level of CD14+CD16+ monocytes is a sensitive marker for the biocompatibility of HD membranes.  相似文献   
35.
BACKGROUND: Renal replacement therapy is of vital importance in the treatment of crush syndrome victims, who are frequently encountered after catastrophic earthquakes. The Marmara earthquake, which struck Northwestern Turkey in August 1999, was characterized by 477 victims who needed dialysis. METHOD: Within the first week of the disaster, questionnaires containing 63 clinical and laboratory variables were sent to 35 reference hospitals that treated the victims. Information considering the features of dialyses obtained through these questionnaires was submitted to analysis. RESULTS: Overall, 639 casualties with renal complications were registered, 477 of whom (mean age 32.3 +/- 13.7 years, 269 male) needed dialysis. Among these, 452 were treated by a single dialysis modality (437 intermittent hemodialysis, 11 continuous renal replacement therapy and 4 peritoneal dialysis), while 25 victims needed more than one type of dialysis. In total, 5137 hemodialysis sessions were performed (mean 11.1 +/- 8.0 sessions per patient) and mean duration of hemodialysis support was 13.4 +/- 9.0 days; this duration was shorter in the non-survivors (7.0 +/- 8.7 vs. 10.0 +/- 9.8 days, P = 0.005). Thirty-four victims who underwent continuous renal replacement therapy had higher mortality rates (41.2 vs. 13.7%, P < 0.0001). Only eight victims were treated by peritoneal dialysis, four of whom also required hemodialysis or continuous renal replacement therapy. The mortality rate in the dialyzed victims was 17.2%, a significantly higher figure compared to the mortality rate of the non-dialyzed patients with renal problems (9.3%; P = 0.015). CONCLUSION: Substantial amounts of dialysis support may be necessary for treating the victims of mass disasters complicated with crush syndrome. Dialyzed patients are characterized by higher rates of morbidity and mortality.  相似文献   
36.
The in vitro activity of fluconazole and Melaleuca alternifolia (tea tree) oil was evaluated against 99 vaginal Candida strains by the broth microdilution and disc diffusion methods. The microdilution method was performed in accordance with NCCLS-M27A guidelines. An investigational method was used for the disc diffusion test. Fluconazole and tea tree oil minimum inhibitory concentrations (MICs) obtained at 48 h tended to increase 1- to 2-fold or remain the same compared to 24 h readings for most of the isolates tested. C. krusei and C. norvegensis had significantly higher MICs and smaller inhibition zones for fluconazole compared to other species. Tea tree oil MICs were found to be similar, in general, for all Candida spp. tested. The geometric mean MIC of tea tree oil for all isolates was 2.2% (range, 0.25-4%) at 24 h and 3.0% (range, 1-8%) at 48 h. Tea tree oil mean inhibition zone diameter was 24 mm (range, 14-42 mm) at 24 h and 15.8 mm (range, 10-35 mm) at 48 h. In vitro activity of tea tree oil against fluconazole-resistant Candida strains was of particular interest. The isolates had similar tea tree oil MICs and inhibition zone diameters regardless of their fluconazole susceptibility profile. Tea tree oil MIC ranges (inhibition zone diameter ranges) were 2-4% (12-21 mm) and 2% (35 mm) at 48 h for C. krusei and C. norvegensis, respectively. These results suggest that tea tree oil MICs of the fluconazole-resistant isolates are comparable to those of fluconazole-susceptible isolates. This in vitro finding is promising for potential use of topical tea tree oil formulations in the treatment of candidiasis due to fluconazole-resistant strains.  相似文献   
37.
Secondary septorhinoplasty often requires a large amount of tissue, and autogenous costal cartilage is one type of grafting material that can be used in these cases. In this study, 20 patients with severe nasal deformity received autogenous costal cartilage grafts. Nineteen of the 20 cases were revisions. Costal cartilage grafts were used for structural and nonstructural purposes in these patients. Follow-up ranged from 8 to 32 months. The complications included 1 patient with early wound infection and 3 with minor warping. There were no problems with graft resorption or extrusion. Other than temporary pain, there were also no complications at the donor sites. We conclude that the autogenous costal cartilage graft is an outstanding material for volume filling and structural support when large amounts of tissue are needed in septorhinoplasty.  相似文献   
38.
BACKGROUND: Postoperative dissection in some patients is related to manipulation of the aorta and accounts for 3% to 5% of deaths after cardiac surgery. METHODS: Between 1987 and 1999, 109 patients with previous cardiac operations were treated for chronic type A dissection. In 31 of the patients, the etiology was related to aortic manipulation. Twenty-one patients (17 men, 4 women; 67+/-13 years of age) had isolated coronary artery bypass grafting (CABG) as their first operation and were reviewed. The interval between operations was 52.9+/-47.3 months. RESULTS: Reoperation was elective in 11 patients, urgent in 10 patients. Median maximal aortic diameter was 6.8+/-2.1 cm; 9 patients had major aortic insufficiency. The intimal tear was at the partial occlusion clamp site in 12 patients (57.1%), at the cross-clamping site in 4 patients (19.1%), and at the proximal anastomosis in 1 patient (4.8%); 4 patients (19.1%) had multiple tears at several sites. Cystic media necrosis was present in 9.5% of the patients, severe atherosclerosis in 47.6% of the patients, and 42.9% of the patients had both. Nine patients (42.9%) underwent a modified Bentall procedure, 12 patients (57.1%) underwent a supracoronary anastomosis, and all had open distal anastomosis. There were two (9.5%) hospital deaths and three (14.3%) postoperative strokes. Freedom from cardiac or aorta-related mortality was 85.7% at a mean follow-up of 49.3 months. CONCLUSIONS: In patients who develop type A dissection of the aorta after previous CABG, the intimal tear most often is at partial occlusion clamp site. This complication is associated with morbidity and mortality. It remains to be seen whether the use of partial occlusion clamps on the pulsating and often diseased aorta during off-pump coronary artery bypass (OPCAB) will increase the risk of delayed iatrogenic dissections.  相似文献   
39.
40.
Definition of malformations of the tragus is important for terminology and treatment. Most common entities are the skin tag, accessory tragus, preauricular sinus, and cyst, whereas macrotragus is an uncommon and unaddressed deformity that should be distinguished from these. In this report, three cases with diagnosis of the macrotragus are presented. The tragus was uniformly large and displaced anteriorly, and external auditory meatus was not obliterated in all cases. For correction, excision of the excess tragal cartilage and skin was performed. In all cases, bilaterally symmetric tragus was achieved. There were no complications in the early postoperative period and there was no enlargement after 6 months of observation. Macrotragus and accessory tragus are different entities that should be distinguished for accurate diagnosis. They have similar histopathological but distinct anatomical characteristics. Although both are treated by a simple excision, in the case of macrotragus, special effort should be taken to leave enough cartilage to restore normal tragal contours. Presented at the 5th Congress of the Balkan Association for Plastic, Reconstructive Aesthetic Surgery, Kuşadası, Turkey, May 22–26, 2007.  相似文献   
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