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91.
Cationic block copolymers spontaneously assemble via electrostatic interactions with DNA molecules in aqueous solution giving rise to micellar structures that protect the DNA from enzymatic degradation both in vitro and in vivo. In addition, we have previously shown that they are safe, not immunogenic and greatly increased antigen-specific CTL responses following six intramuscular inoculations of a very low dose (1 μg) of the vaccine DNA as compared to naked DNA. Nevertheless, they failed to elicit detectable humoral responses against the antigen. To gain further insight in the potential application of this technology, here we show that a shorter immunization protocol based on two DNA intramuscular inoculations of 1 μg of DNA delivered by these copolymers and a protein boost elicits in mice broad (both humoral and cellular) and long-lasting responses and increases the antigen-specific Th1-type T cell responses and CTLs as compared to priming with naked DNA. These results indicate that cationic block copolymers represent a promising adjuvant and delivery technology for DNA vaccination strategies aimed at combating intracellular pathogens.  相似文献   
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Background  

Total hip arthroplasty is a successful surgery, that fails at a rate of approximately 10% at ten years from surgery. Causes for failure are mainly aseptic loosening of one or both components partially due to wear of articular surfaces and partially to design. The present analysis aimed to identify risk factors and quantify their effects on aseptic failure.  相似文献   
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A survey was performed on the radiotherapy practice of malignant pleural mesothelioma in The Netherlands and Belgium in 2002. Thirty-eight out of 47 centres (81%) responded. Prophylactic radiotherapy to intervention sites is given by 32/38 (84%) centres, with all centres offering palliative radiation. For both prophylactic and palliative indications, all centres use hypo-fractionated schedules. The present study shows that in the radiotherapy community in The Netherlands and in Belgium, a de facto consensus exists that both prophylactic and symptomatic radiotherapy to intervention sites of malignant pleural mesothelioma are effective and that hypo-fractionated schedules should be used.  相似文献   
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Two new T cell subsets may be involved in allergic rhinitis (AR) pathogenesis: Th17 and T regulatory cells, mainly producing IL-17 and TGF-β respectively. Successful Sublingual Immunotherapy (SLIT) induces relevant immunological changes, thus the aim of this study was to evaluate serum IL-17 and TGF-β levels in AR patients treated with SLIT for 2 years. Patients' blood samples were collected before initiating SLIT (baseline), three months after the end of the first pre-seasonal SLIT course, and at the end of the second pre-seasonal course. IL-17 was detectable only in the most severe allergic patients. SLIT significantly induced an increase in serum TGF-β levels. There was moreover a significant relationship between TGF-β and symptom severity and drug use at the end of the study. Therefore, this study provides clinically relevant evidence that two pre-seasonal SLIT courses may significantly affect serum TGF-β levels.  相似文献   
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OBJECTIVE: The effects of major lung resections on cardiac function in the medium and long term have not been thoroughly evaluated. We have studied right heart function with serial Doppler echocardiography in patients undergoing lobectomy and pneumonectomy during 4 years of follow-up after surgery. METHODS: Thirty-six patients undergoing lobectomy and 15 receiving pneumonectomy were evaluated with one- and two-dimensional Doppler standard transthoracic echocardiography before surgery and 1 week, 3 months, 6 months, 1 year, and 4 years postoperatively. We have studied the right midventricular diastolic diameter (RVDD), the right ventricle free wall thickness, the tricuspid valve insufficiency (TVI) and regurgitation jet (TRJ), and the pulmonary artery systolic pressure (PASP). RESULTS: None of the patients died within the first postoperative year. After lobectomy there were no significant modifications of any variable at any time. RVDD progressively increased after pneumonectomy (26.5+/-2.2mm preoperatively vs 34.3+/-7.6 at 4 years; p<0.001). Four years after surgery all patients undergoing pneumonectomy had moderate TVI while only 55% of patients receiving lobectomy showed it (low grade in 50% and moderate in 5%). In this group of patients PASP increased from 26.1+/-2.6 mmHg preoperatively to 34.3+/-7.6 mmHg at 4 years (p<0.00001). CONCLUSIONS: Right ventricle modifications are clearly evident after pneumonectomy and even if they do not show a clear clinical impact they should not be neglected.  相似文献   
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The 3-methoxy-4-hydroxyphenylglycol (MHPG) flow, the creatinine flow in 24 h urine and the plasma creatinine level were determined in 42 psychiatric control patients. The creatinine clearance was calculated. The relationship between MHPG flow in 24 h urine and creatinine clearance, creatinine flow, 24 h urinary output, age, sex and weight of the patient were studied by means of single and multiple regression methods. The MHPG flow was significantly correlated with creatinine clearance (r= 0.597), creatinine flow (r = 0.646) and sex of the patient (rpb = 0.434). The variance of the MHPG flow can be explained by the regression with creatinine flow, age and urinary output for at maximum 51.5%. These variables have to be taken into account for the interpretation of data concerning the MHPG flow in subsequent experimental designs. The results of the measurements of the MHPG flow can best be expressed as the residual values obtained after partialling out the predictable component calculated by multiple regression with creatinine flow, age and 24 h urine output.  相似文献   
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