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31.
Vaccination with recombinant outer surface protein A (OspA) from Borrelia burgdorferi provides excellent antibody-mediated protection against challenge with the pathogen in animal models and in humans. However, the bactericidal antibodies are ineffective in the reservoir host, since OspA is expressed by spirochetes only in the vector, but rarely, if at all, in mammals. Using an artificially generated immune serum (anti-10(8) spirochetes) with high protective potential for prophylactic and therapeutic treatment, we have now isolated from an expression library of B. burgdorferi (strain ZS7) three novel genes, zs7.a36, zs7.a66 and zs7.a68. All three genes are located, together with ospA/B, on the linear plasmid lp54, and are expressed in vitro and in ticks. At least temporarily two of them, ZS7.A36 and ZS7.A66, are also expressed during infection. The respective natural antigens are poorly immunogenic ininfected normal mice but elicited antibodies in Lyme disease patients. We show that recombinant preparations of ZS7.A36, ZS7.A66 and ZS7.A68 induce functional antibodies in rabbits capable of protecting immunodeficient mice against subsequent experimental infection. These findings suggest that all three recombinant antigens represent potential candidates for a "second generation" vaccine to prevent and/or cure Lyme disease.  相似文献   
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Reliability of the Dominic-R, a. questionnaire combining visual and auditory stimuli, was tested in 340 community children aged 6 to 11 years. Test-retest reliability of symptoms of, and of symptom scores of, DSM-III-R disorders including simple phobias, separation anxiety disorder, overanxious disorder, depression/dysthymia, attention deficit/ hyperactivity disorder, oppositional defiant disorder, and conduct disorder was assessed. Most symptoms yielded kappas greater than .40, and ICCs ranged from .74 to .81. In conclusion, reliability of the Dominic-R compares favourably with that of other child assessment questionnaires.  相似文献   
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The management of febrile infants 3 to 36 months old has been an ongoing topic of controversy, particularly with respect to occult bacteremia. Published strategies and algorithms have been developed to aid the clinician in the evaluation and management of these children. With the licensure and implementation of universal hepatovalent conjugate pneumococcal (PCV7) vaccination in infants, it is worthwhile to reexamine the data on which these recommendations were based. In this article, we will discuss the management of occult bacteremia in young febrile children in the era of PCV7 immunization and propose a management strategy for young febrile children.  相似文献   
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PURPOSE Positron emission tomography (PET) has been used in grading of CNS tumors in adults, whereas studies of children have been limited. PATIENTS AND METHODS Nineteen boys and 19 girls (median age, 8 years) with primary CNS tumors were studied prospectively by fluorine-18 2-fluoro-2-deoxy-D-glucose (FDG) PET with (n = 16) or without (n = 22) H(2)(15)O-PET before therapy. Image processing included coregistration to magnetic resonance imaging (MRI) in all patients. The FDG uptake in tumors was semiquantitatively calculated by a region-of-interest-based tumor hotspot/brain index. Eight tumors without histologic confirmation were classified as WHO grade 1 based on location, MRI, and clinical course (22 to 42 months). Results Four grade 4 tumors had a mean index of 4.27 +/- 0.5, four grade 3 tumors had a mean index of 2.47 +/- 1.07, 10 grade 2 tumors had a mean index of 1.34 +/- 0.73, and eight of 12 grade 1 tumors had a mean index of -0.31 +/- 0.59. Eight patients with no histologic confirmation had a mean index of 1.04. For these 34 tumors, FDG uptake was positively correlated with malignancy grading (n = 34; r = 0.72; P < .01), as for the 26 histologically classified tumors (n = 26; r = 0.89; P < .01). The choroid plexus papilloma (n = 1) and the pilocytic astrocytomas (n = 3) had a mean index of 3.26 (n = 38; r = 0.57; P < .01). H(2)(15)O-uptake showed no correlation with malignancy. Digitally performed PET/MRI coregistration increased information on tumor characterization in 90% of cases. CONCLUSION FDG PET of the brain with MRI coregistration can be used to obtain a more specific diagnosis with respect to malignancy grading. Improved PET/MRI imaging of the benign hypermetabolic tumors is needed to optimize clinical use.  相似文献   
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Extended lymphadenectomy (D2) in patients with early gastric cancer.   总被引:3,自引:0,他引:3  
AIMS: To investigate the survival benefit of extended lymphadenectomy (D2) in EGC patients in one European Institution. METHODS: A review was made of our prospective gastric database from January 1980 to December 2001. Of 527 patients with primary gastric adenocarcinoma, 119 with EGC underwent potentially curative resection (R0) with D2 lymphadenectomy. RESULTS: There were two post-operative deaths. Of the 117 evaluable cases, 96 were classified as N0 and 21 as N+, with metastases in the perigastric lymph nodes (level 1) in 13, and beyond this site (level 2) in eight. Five-year survival was 85.9 and 83.0% in N0 and N+ patients, respectively. During a median follow-up of 90 months, five of the eight patients with level 2 metastases died of recurrent disease and three were alive. The estimated survival benefit for 119 patients with EGC was 2.5% (3/119 cases). CONCLUSIONS: In patients with EGC, metastases to level 2 are rare. Our results indicate that D2 lymphadenectomy has a limited survival benefit and that in these cases a less extensive lymphadenectomy (D1) could be performed.  相似文献   
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In Ontario, some court cases have involved attempts to sue social hosts for damage caused by the behaviour of drunken guests. Such legal actions give rise to the question of risks and responsibilities accruing to social hosts who serve alcohol. Using a sample of 1395 male and female adult residents of Ontario, the authors present self-report survey data concerning frequency of serving alcohol to guests, methods of handling guests who have too much to drink, prevention of drunk driving, service of alcohol to underage persons, and offering food and non-alcoholic drinks when serving alcohol at home. The results show high levels of intended safe practices overall, along with some areas for concern. Notably, about one-third of the total sample had had guests judged to be too drunk to drive home safely. A multivariate analysis confirmed significant differences associated with sex and age. The authors recommend the creation and evaluation of programmes to upgrade home-hosting skills as an adjunct to systemic alcohol control policies.  相似文献   
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