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991.
The most commonly used method for detection ofpathogenic bacteria in cerebrospinal fluid (CSF) speci mens of clinical laboratories is isolation and identificationof the causative agents by cultural method, biochemicaland serological t…  相似文献   
992.
Neutralizing antibody (nAb) response is sporadic and has limited potency and breadth during infection with human immunodeficiency virus type 1 (HIV-1). In rare cases, broad and potent nAbs are actually induced in vivo. Identifying specific epitopes targeted by such broad and potent nAb response is valuable in guiding the design of a prophylactic vaccine aimed to induce nAb. In this study, we have defined neutralizing epitope usage in 7 out of 17 subjects with broad and potent nAbs by using targeted mutagenesis in known neutralizing epitopes of HIV-1 glycoproteins and by using in vitro depletion of serum neutralizing activity by various recombinant HIV-1 glycoproteins. Consistent with recent reports, the CD4 binding site (CD4BS) is targeted by nAbs in vivo (4 of the 7 subjects with defined neutralizing epitopes). The new finding from this study is that epitopes in the gp120 outer domain are also targeted by nAbs in vivo (5 of the 7 subjects). The outer domain epitopes include glycan-dependent epitopes (2 subjects), conserved nonlinear epitope in the V3 region (2 subjects), and a CD4BS epitope composed mainly of the elements in the outer domain (1 subject). Importantly, we found indication for epitope poly-specificity, a dual usage of the V3 and CD4BS epitopes, in only one subject. This study provides a more complete profile of epitope usage for broad and potent nAb responses during HIV-1 infection.  相似文献   
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Drawing on emotional security theory, this study examined linkages between interparental aggression, infant self‐regulatory behaviors, and patterns of physiological and behavioral stress responses in a diverse sample of 735 infants residing in predominately low‐income, non‐metropolitan communities. Latent profile analysis revealed four classes of adrenocortical and behavioral stress‐response patterns at 7 months of age, using assessments of behavioral and cortisol reactivity to an emotion eliciting challenge, as well as global ratings of the child's negative affect and basal cortisol levels. The addition of covariates within the latent profile model suggested that children with more violence in the home and children who used less caregiver‐oriented regulation strategies were more likely to exhibit a pattern of high cortisol reactivity with moderate signs of distress rather than the average stress response, suggesting possible patterns of adaptation in violent households. © 2011 Wiley Periodicals,Inc. Dev Psychobiol 54: 685–699, 2012.  相似文献   
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The ability of influenza vaccination to provide cross-protection against heterovariant influenza strains was evaluated in a double-blind, randomized, trial in north-east Italy during the winter of 2005-2006. Of 238 adult subjects with underlying chronic diseases, 120 received MF59-adjuvanted subunit vaccine (Sub/MF59) and 118 received a conventional subunit vaccine (Subunit). Immunogenicity was measured for A/H3N2 and B influenza strains against both the homologous vaccine strains (A/New York/55/2004 and B/Jiangsu/10/2003), and the heterovariant strains recommended for the 2006-2007 season (A/Wisconsin/67/2005 and B/Malaysia/2506/2004). Although both vaccines conferred serological protection against the homologous vaccine strains and the 2006-2007 heterovariant A/H3N2 strain for a majority of subjects, the antibody response was highest in the Sub/MF59 vaccine group. For example, MF59-adjuvanted vaccination conferred significantly greater (P = 0.002) protection against the heterovariant A/H3N2 strain than the conventional subunit vaccine (79.2% vs. 61.0% of subjects, respectively). In conclusion, these results demonstrate that protection provided by influenza vaccination in adults affected by chronic diseases is lower against heterovariant strains than for homologous strains. However, addition of MF59 adjuvant to a subunit vaccine enhances immunogenicity against the A/H3N2 heterovariant strain, conferring broader protection than a conventional subunit vaccine in this population, who are at higher risk of influenza-related complications.  相似文献   
997.
Hospital-acquired methicillin-resistant Staphylococcus aureus (MRSA) strains are no longer limited to acute-care hospitals but have now spread to other healthcare settings such as long-term-care facilities (LTCFs), in most of which they are endemic. In Europe, few studies have addressed the MRSA situation in LTCFs. A cross-sectional study to determine MRSA prevalence and factors associated with S. aureus carriage in community LTCF residents is reported here. Nasal and decubitus ulcer cultures were performed for residents of nine community LTCFs. Residents were classified as MRSA carriers, methicillin-susceptible S. aureus carriers and non-carriers. Overall, 1377 nasal swabs and 82 decubitus ulcer cultures were performed. MRSA was isolated from 15.5% and 59.0% of the former and latter, respectively. The prevalence of MRSA colonization was 16.8% (95% CI  14.9–18.8), varying from 6.7% to 35.8% (p <0.001) among LTCFs. Several independent variables were related to MRSA colonization. It is noteworthy that residents in an LTCF with fewer than 150 beds had at least a two-fold higher probability of being MRSA carriers. Modifiable factors were medical devices, decubitus ulcers and previous antibiotic treatment. An age of 85 years or older, a Charlson index ≥2 and transfer from an acute-care facility were non-modifiable factors also related to MRSA colonization. A high MRSA prevalence among residents in community LTCFs in Spain, with great variability among facilities, was found. The factors identified as being associated with MRSA colonization could be prevented by the implementation of several measures. Control strategies need to be coordinated between LTCFs and acute-care hospitals.  相似文献   
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目的:探讨高血压性脑出血的低场磁共振诊断价值。方法:对80例高血压性脑出血病人进行低场磁共撅扫描,观察分析其病灶的形态与信号变化情况。结果:病灶主要位于两侧基底节区和丘脑,以肾形多见,在超急性期病灶即表现为高信号(T1加权、T2加权),信号欠均匀,随着时间的延续,病灶信号逐渐演变为外高中低信号和均匀高信号,最后呈T1加投低信号,T2加权高信号。其中,多发性出血占117%,反复性出血占6.25%。深部脑出血可破入脑室(约占12.5%)。结论:对于急性脑出血低场磁共振扫描与CT检查具有同等诊断价值。  相似文献   
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