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991.
Comparative analysis of effects of cytokine gene adjuvants on DNA vaccination against Mycobacterium tuberculosis heat shock protein 65 总被引:11,自引:0,他引:11
Baek KM Ko SY Lee M Lee JS Kim JO Ko HJ Lee JW Lee SH Cho SN Kang CY 《Vaccine》2003,21(25-26):3684-3689
DNA-based vaccines generate potent cellular immunity as well as humoral immunity. It seems evident that cytokines play a crucial role in generation of effector T cell subsets and in determining the magnitude of the response by DNA vaccines. In this study, we compared the effects of several TH1 cytokine genes as adjuvant in DNA vaccination using mycobacterial Hsp65 as a model antigen. Our results demonstrated that although the overall immune response to Hsp65 was enhanced by co-injection of Hsp65 DNA with cytokine genes, each cytokine gene was shown to affect different immune response elements. Co-injection of Hsp65 DNA with IL-12 or GM-CSF led to an increase in IFN-gamma production and represented potent protections against Mycobacterium tuberculosis challenge, while that with Eta-1, IL-12 or IL-18 gene led to an elevated IgG2a/IgG1 ratio. Interestingly, co-administration of Flt3L gene was shown to enhance the Ag-specific CTL response. These results show that the direction and magnitude of immune response in DNA vaccination against Hsp65 of M. tuberculosis could be modulated in different ways by co-injection of an appropriate cytokine gene as adjuvant. 相似文献
992.
Deltamethrin, a synthetic pyrethroid pesticide contaminating aquatic ecosystems as a potential toxic pollutant, was investigated in the present study for acute toxicity. Guppy fish (Poecilia reticulata) were selected for the bioassay experiments. The 48-h LC50 was determined for the guppies. The experiments were repeated three times and a total of 210 guppies were used. The static test method of acute toxicity test was used. In addition, behavioral changes at each deltamethrin concentration were determined for the individuals. Data obtained from the deltamethrin acute toxicity tests were evaluated using the Probit Analysis Statistical Method. The 48-h LC50 value for guppy was estimated as 5.13 microg/L. 相似文献
993.
The objectives were to investigate the effects of formulation variables on the release of drug and to optimize the formulation of chitosan microparticles loaded with drug for controlled release using response surface methodology. Chitosan microparticles were prepared by dropping a chitosan solution into sodium tripolyphosphate (TPP) through ionic cross-linking. The release behaviour of felodipine as a model drug was affected by preparation variables. A central composite design was used to evaluate and optimize the effect of preparation variables, chitosan concentration (X1), the pH of the TPP solution (X2) and cross-linking time (X3) on the cumulative per cent drug release (Y) in 24 h. Chitosan concentration and cross-linking time affected negatively the release of felodipine, while the pH of the TPP did so positively and was the highest influential factor. The optimum rate of drug release, 100% in 24 h, was achieved at 1.8% chitosan concentration, a pH 8.7 for the TPP solution and 9.7 min cross-linking time. 相似文献
994.
Elderly (80+ year old) individuals are the fastest-growing segment of the U.S. population. The objective of this study was to use population-based data to examine trends in the number of elderly undergoing major general, vascular, and cardiothoracic surgical procedures. California inpatient data from 1990-2000 was used to identify patients undergoing six procedures: abdominal aortic aneurysm repair (AAA), coronary artery bypass graft (CABG), carotid endarterectomy (CEA), colon resections, lung resections, and pancreatic resections. Despite comprising only 2.7 per cent of the California population, elderly patients were a significant percentage (6-22%) of the caseloads for the six procedures examined. For all six procedures, the percentage of patients that were elderly increased during the study period. The age-specific incidence rates for elderly individuals increased significantly for three of these procedures (CABG, CEA, lung resection), remained unchanged for two (AAA, pancreas resection), and decreased for one (colon resection). Elderly patients are a large and growing part of surgical caseloads. In the near future, the number of elderly individuals in the California state and the U.S. populations will increase dramatically (41% and 35% between 2000 and 2020). To provide the best quality of care, surgeons should embrace research, training, and educational opportunities regarding the treatment of elderly patients. 相似文献
995.
Fukuda I Imazuru T Osaka M Watanabe K Meguro K Wada M 《The Annals of thoracic surgery》2003,76(4):1293-1295
Five patients who had delayed stroke after cardiac surgery underwent intraarterial administration of a fibrinolytic agent for thromboembolism (n = 4) or thrombosis (n = 1) of the cerebral artery. Complete recanalization of the occluded artery was obtained in 3 patients and partial recanalization in 2. Additional angioplasty for basilar artery stenosis was performed in 1 patient. No patients exhibited rebleeding into the pericardial space or wound bleeding. All patients survived with moderate or full functional recovery. Immediate cerebral angiography and local thrombolysis may improve functional outcome and survival in patients with postcardiotomy cerebral thromboembolism. 相似文献
996.
Improved survival for adenocarcinoma of the ampulla of Vater: fifty-five consecutive resections 总被引:12,自引:0,他引:12
Duffy JP Hines OJ Liu JH Ko CY Cortina G Isacoff WH Nguyen H Leonardi M Tompkins RK Reber HA 《Archives of surgery (Chicago, Ill. : 1960)》2003,138(9):941-8; discussion 948-50
HYPOTHESIS: After resection of an adenocarcinoma of the ampulla of Vater, certain clinical and pathologic characteristics influence long-term survival. DESIGN: Retrospective case series. SETTING: Major academic medical and pancreatic surgical center. PATIENTS: Fifty-five consecutive patients who underwent Whipple resection for ampullary adenocarcinoma from 1988 through 2001. INTERVENTIONS: Pylorus-preserving Whipple resection in 32 patients and standard Whipple resection in 23 patients. MAIN OUTCOME MEASURES: Postoperative survival. A multivariate Cox proportional hazards model was used to determine the effects of various factors on long-term survival after resection. RESULTS: There were no operative deaths, and all patients left the hospital. After a mean follow-up of 46.9 months, the overall 5-year Kaplan-Meier survival estimate was 67.7%. The median survival of the entire group has not yet been reached. Five-year postoperative survival estimates for node-negative (n = 32) and node-positive patients (n = 23) were 76.5% and 53.4%, respectively (P =.26). Patients whose tumors demonstrated perineural invasion (n = 12) had a 5-year survival estimate of 29.2% vs 78.8% for those whose did not (P<.001). On multivariate analysis, the absence of perineural invasion (P<.001) was an independent predictor of significantly improved postoperative survival. CONCLUSIONS: Compared with previous reports from our own and other centers, this series demonstrates improved postoperative survival by 10% to 20% in patients undergoing Whipple resection for adenocarcinoma of the ampulla of Vater. The reasons for this improved outcome are unclear, and the effect of adjuvant treatment cannot be determined from this analysis. The major factor associated with prolonged survival was the absence of perineural invasion in the resected tumor specimen. 相似文献
997.
Evaluation of a novel sutureless anastomotic connector: from endothelial function to mid-term clinical and angiographic follow-up 总被引:1,自引:0,他引:1
Verma S Fedak PW Ko L Cusimano RJ Walton NA Parker JD Yau TM 《The Journal of thoracic and cardiovascular surgery》2003,126(5):1555-1560
OBJECTIVES: We evaluated the effect of the St Jude Medical sutureless anastomotic connector on endothelium-dependent and -independent saphenous vein graft relaxation, as well as on clinical outcomes and graft patency in patients. METHODS: Human saphenous vein grafts were assigned to control or connector groups (loaded for 1 or 5 minutes; n = 18). Isometric dose-response curves to endothelium-dependent and -independent (sodium nitroprusside) vasodilators were constructed in saphenous vein grafts precontracted with phenylephrine. Thrombin-mediated vasorelaxation, an early determinant of saphenous vein graft failure, was also evaluated. Percent maximum relaxation was compared between groups. Patients in whom the St Jude Medical connector was employed underwent clinical follow-up, stress tests, and angiography 6 to 12 months postoperatively. RESULTS: A23187-induced endothelium-mediated relaxation, sodium nitroprusside-induced endothelium-independent relaxation, and thrombin-mediated vasorelaxation did not differ between control and connector saphenous vein grafts at either time point studied. Twenty-seven patients received St Jude Medical connectors. There was no hospital mortality; patients were followed for 679 +/- 241 days. There was 1 late death; the connector saphenous vein graft was patent at postmortem. All connector saphenous vein grafts were patent at follow-up angiography. Four grafts had stenoses (30%-60%), without symptoms or requirement for intervention. All hand-sewn saphenous vein grafts were also patent. CONCLUSIONS: The St Jude Medical connector does not impair endothelium-dependent vasorelaxation. In patients, patency of the connector saphenous vein grafts 6 to 12 months postoperatively was 100% but 22% of grafts had non-flow-limiting stenoses at or near the connector. Further long-term studies are required to confirm the safety of the St Jude Medical connector with regards to endothelial function and restenosis. 相似文献
998.
AIM: The purpose of this study was to investigate the effect of high dose oral creatine supplementation on anaerobic capacity of elite wrestlers. METHODS: Experimental design: comparative randomized design. Setting: Wingate anaerobic tests of the participants were taken at the Human Performance Laboratory of the Department of Physical Education and Sports in The Middle East Technical University, Ankara, Turkey. Participant: 20 active international level wrestlers participated (22 to 27 years old). Interventions: the daily dosage of creatine or placebo was divided into 4 equal amounts (5 gx4 = 20 g). Every 5 g of supplement was dissolved in 250 ml water and it was given to participants 1 hour before breakfast, lunch, dinner, and workout session. Measures: subjects underwent a 30-s Wingate Anaerobic tests until exhaustion in pre- and post-tests. After the pretest measurements were completed, participants were classified as creatine (Cr., n=10) and placebo (Pl., n=10) groups with regard to their average anaerobic power scores obtained during the test. RESULTS: Results of paired "t"-test revealed that there was no significant change in placebo group between pre- and post-test in average and peak anaerobic power. However, average and peak power mean scores obtained from post-test (8.123+/-0.448 W/kg and 10.523 +/-1.004 W/kg) were significantly (p<0.01) higher than pretest (7.233+/-0.483 W/kg and 8.992+/- 0.665 W/kg) for creatine group. Results of the independent "t"-test also indicated that the mean gained scores of creatine group in average and peak power were significantly higher than placebo group (p<0.01). CONCLUSION: This study demonstrates that short-term high dose oral creatine supplementation has an ergogenic effect on anaerobic capacity of elite wrestlers. 相似文献
999.
Polyethylene wear in total hip prostheses: the influence of direction of linear wear on volumetric wear determined from radiographic data 总被引:1,自引:0,他引:1
Kosak R Antolic V Pavlovcic V Kralj-Iglic V Milosev I Vidmar G Iglic A 《Skeletal radiology》2003,32(12):679-686
Purpose To develop a new mathematical model for calculating the volumetric wear of polyethylene cups from known values of the radius of the prosthesis head, the extent of linear wear and the direction of linear wear determined from standard antero-posterior radiographs.Method A new mathematical model was developed. The results of this new mathematical model were compared with the results obtained using the standard, frequently used mathematical model, which takes into consideration only the radius of the prosthesis head and the extent of linear wear of the polyethylene cups. The results of both mathematical models were further compared with the results obtained by direct measurement of volumetric wear using the fluid displacement method.Results Comparison of the mathematical models shows that the average volumetric wear calculated using the new mathematical model is 8.5% smaller than the average volumetric wear determined by the fluid displacement method, while the average volumetric wear calculated by standard mathematical model is 17.5% higher. The results of the new mathematical model are, thus, notably less biased than those of the standard one.Conclusion In calculating the volumetric wear from antero-posterior radiographs, not only the radius of the prosthesis head and the extent of the linear wear but also the direction of the latter has to be considered. 相似文献
1000.
Soon-A Hwang Joon Beom Seo Byeong-Kyoo Choi Kyung-Hyun Do Sung Min Ko Soo-Hyun lee Jin Seong Lee Jae-Woo Song Koun-Sik Song Tae-Hwan Lim 《Korean journal of radiology》2003,4(3):153-156