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11.
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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OBJECTIVE: To evaluate the dynamics of bacterial contamination of healthcare workers' (HCWs) hands during neonatal care. SETTING: The 20-bed neonatal unit of a large acute care teaching hospital in Geneva, Switzerland. METHODS: Structured observation sessions were conducted. A sequence of care began when the HCW performed hand hygiene and ended when the activity changed or hand hygiene was performed again. Alcohol-based handrub was the standard procedure for hand hygiene. An imprint of the five fingertips of the dominant hand was obtained before and after hand hygiene and at the end of a sequence of care. Regression methods were used to model the final bacterial count according to the type and duration of care and the use of gloves. RESULTS: One hundred forty-nine sequences of care were observed. Commensal skin flora comprised 72.4% of all culture-positive specimens (n = 360). Other microorganisms identified were Enterobacteriaceae (n = 55, 13.8%); Staphylococcus aureus (n = 10, 2.5%); and fungi (n = 7, 1.8%). Skin contact, respiratory care, and diaper change were independently associated with an increased bacterial count; the use of gloves did not fully protect HCWs' hands from bacterial contamination. CONCLUSIONS: These data confirm that hands become progressively contaminated with commensal flora and potential pathogens during neonatal care, and identify activities at higher risk for hand contamination. They also reinforce the need for hand hygiene after a sequence of care, before starting a different task, and after glove removal.  相似文献   
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We describe a case of Munchausen's syndrome by proxy in a 12 years old child. The administration of glibenclamide by the mother led to severe hypoglycemias in the child, who underwent various instrumental researches and a subtotal pancreatectomy before the final diagnosis could be reached. The diagnosis also was possible with the substantial help of an accurate psychological survey. The case solution, with disappearance of hypoglycemias, was made possible by the removal of the maternal presence settled by the juvenile court.  相似文献   
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Benzo[a]pyrene diol epoxide adducts with hemoglobin (Hb) weremeasured to detect human exposure to environmental benzo[a]pyrenefrom traffic exhaust. Benzo[a]pyrene tetrahydrotetrols (BPTs)released from Hb after acid hydrolysis were quantitated by gaschromatography-mass spectrometry after immunoaffinity chromatography.Fifty three newspaper vendors were enrolled. The median adductconcentration was 0.3 fmol BPTs/mg Hb in high density traffic-exposedvendors and  相似文献   
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The authors conducted a clinical and radiographic study on a group of 43 patients with hip arthroprostheses selected from the three-year period from 1984 to 1987, characterized by no immediate postoperative complications, no positional defects on X-ray examination, and with a Renther test greater than 1. Prostheses were cemented, cementless and combined. Scintigraphy was evaluated for areas of subdivision in the proximal end of the femur and acetabulum, making a semi-quantitative comparison of the intensity of captation of each area with that of the skull and sacroiliac synchondrosis. The authors emphasize that this procedure is both reliable and easy for the early determination (pre-clinical and pre-radiographic) of any complications. A scintigraphic examination of the single areas was also capable of revealing the site and entity of prosthetic bone-to-implant interactions. According to the results reported, PCA prostheses seem to be characterized by better biocompatibility.  相似文献   
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Sir, The comment of Attilio Di Spiezio Sardo et al. was very interesting.They reported the results of their studies on the effects ofintranasal and transdermal  相似文献   
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An extremely rare case of synovial sarcoma localized in the larynx is reported together with a review of 6 similar neoplasms previously reported in this unusual region. In this case, the patient is still tumor free 16 years after therapy.  相似文献   
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