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51.
This multicenter study analyzed Nocardia spp., including extraction, spectral acquisition, Bruker matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) identification, and score interpretation, using three Nocardia libraries, the Bruker, National Institutes of Health (NIH), and The Ohio State University (OSU) libraries, and compared the results obtained by each center. A standardized study protocol, 150 Nocardia isolates, and NIH and OSU Nocardia MALDI-TOF MS libraries were distributed to three centers. Following standardized culture, extraction, and MALDI-TOF MS analysis, isolates were identified using score cutoffs of ≥2.0 for species/species complex-level identification and ≥1.8 for genus-level identification. Isolates yielding a score of <2.0 underwent a single repeat extraction and analysis. The overall score range for all centers was 1.3 to 2.7 (average, 2.2 ± 0.3), with common species generally producing higher average scores than less common ones. Score categorization and isolate identification demonstrated 86% agreement between centers; 118 of 150 isolates were correctly identified to the species/species complex level by all centers. Nine strains (6.0%) were not identified by any center, and six (4.0%) of these were uncommon species with limited library representation. A categorical score discrepancy among centers occurred for 21 isolates (14.0%). There was an overall benefit of 21.2% from repeat extraction of low-scoring isolates and a center-dependent benefit for duplicate spotting (range, 2 to 8.7%). Finally, supplementation of the Bruker Nocardia MALDI-TOF MS library with both the OSU and NIH libraries increased the genus-level and species-level identification by 18.2% and 36.9%, respectively. Overall, this study demonstrates the ability of diverse clinical microbiology laboratories to utilize MALDI-TOF MS for the rapid identification of clinically relevant Nocardia spp. and to implement MALDI-TOF MS libraries developed by single laboratories across institutions.  相似文献   
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53.
The purpose of the present study was to establish the role of DDAH gene polymorphisms in the risk of developing myocardial infarction (MI) in a clinical cohort of Mexican patients. One polymorphism (rs1498373) in the DDAH1 and three in the DDAH2 (rs805304, rs3131383, and rs805305) genes were performed by TaqMan genotyping assays in 473 patients with MI and 447 healthy unrelated controls. Similar distribution of DDAH1 and DDAH2 polymorphisms was observed in MI patients and healthy controls. Under a recessive model adjusted for age, gender, and obesity, the rs805304 C allele was associated with decreased risk of MI (OR = 0.70, 95% CI = 0.51–0.96, P = 0.030). The effect of the polymorphisms on various cardiovascular risk factors was analyzed. Under a recessive model adjusted for age and gender, the DDAH2 rs805304 C allele was associated with decreased risk of obesity (OR = 0.35, 95% CI = 0.22–0.57, P = 0.001). The three DDAH2 polymorphisms were in strong linkage disequilibrium. Our results suggest that the rs805304 C allele was associated with decreased risk of MI and decreased risk of obesity.  相似文献   
54.
The purpose of the present study is to investigate the frequency of HLA-B27 and its alleles in reactive arthritis (ReA) and in ankylosing spondylitis (AS) in Tunisia. HLA-B27 alleles were typed by PCR amplification with sequence-specific primers. We studied 17 patients with ReA associated with urethritis or with gastrointestinal infection; 42 HLA-B27-positive patients with AS and 100 healthy controls. Eleven ReA patients (67.7%) were HLA-B27 positive. There was an increased frequencies of HLA-B27 (P = 7.76 × 10−12, OR = 59.30) and a moderate increase of HLA-B51 (P = 0.015; OR = 4.91) alleles in ReA patients when compared with healthy controls. Four B27 subtypes were identified: B*2702, 05, 09 and B*2712. The distribution of these alleles in the ReA patients was 37.5% for B*2702 and B*2705. Only these two subtypes were detected in 18 (42.8%) and 24 (57.1%), respectively, of the AS patients. B*2709 and B*2712 were relatively rare in ReA patients and were identified in one case each. Our results showed a restricted number of HLA-B27 subtypes associated with ReA and AS. B*2702 and 2705 were common in ReA and AS patients.  相似文献   
55.
Fractionated proton beam radiotherapy for acoustic neuroma   总被引:2,自引:0,他引:2  
Bush DA  McAllister CJ  Loredo LN  Johnson WD  Slater JM  Slater JD 《Neurosurgery》2002,50(2):270-3; discussion 273-5
OBJECTIVE: This study evaluated proton beam irradiation in patients with acoustic neuroma. The aim was to provide maximal local tumor control while minimizing complications such as cranial nerve injuries. METHODS: Thirty-one acoustic neuromas in 30 patients were treated with proton beam therapy from March 1991 to June 1999. The mean tumor volume was 4.3 cm(3). All patients underwent pretreatment neurological evaluation, contrast enhanced magnetic resonance imaging, and audiometric evaluation. Standard fractionated proton radiotherapy was used at daily doses of 1.8 to 2.0 cobalt Gray equivalent: patients with useful hearing before treatment (Gardner-Robertson Grade I or II) received 54.0 cobalt Gray equivalent in 30 fractions; patients without useful hearing received 60.0 cobalt Gray equivalent in 30 to 33 fractions. RESULTS: Twenty-nine of 30 patients were assessable for tumor control and cranial nerve injury. Follow-up ranged from 7 to 98 months (mean, 34 mo), during which no patients demonstrated disease progression on magnetic resonance imaging scans. Eleven patients demonstrated radiographic regression. Of the 13 patients with pretreatment Gardner-Robertson Grade I or II hearing, 4 (31%) maintained useful hearing. No transient or permanent treatment-related trigeminal or facial nerve dysfunction was observed. CONCLUSION: Fractionated proton beam therapy provided excellent local control of acoustic neuromas when treatment was administered in moderate doses. No injuries to the Vth or VIIth cranial nerves were observed. A reduction in the tumor dose is being evaluated to increase the hearing preservation rate.  相似文献   
56.
This article examines the rationale and strategies for surveillance of health-care-associated infections in home-care settings, the challenges of nonhospital-based surveillance, and the feasibility of developing a national surveillance system.  相似文献   
57.
Bile acids alter regulatory pathways in several cell types. The molecular basis for these actions is not fully elucidated, but lithocholyltaurine interacts functionally with muscarinic receptors on gastric chief cells. In the present report, we demonstrate selective interaction of bile acids with Chinese hamster ovary (CHO) cells expressing each of the five muscarinic receptors. Lithocholyltaurine decreases binding of a radioligand to muscarinic M3 receptors, but not to other muscarinic receptors. Sulfated lithocholyltaurine, the major human metabolite, inhibits radioligand binding to muscarinic M1, but not to M2 or M3 receptors. Post-receptor actions of lithocholyltaurine include modulation of acetylcholine-induced increases in inositol phosphate formation and mitogen-activated protein (MAP) kinase phosphorylation. Molecular modeling suggests that the specific and functional interaction of lithocholyltaurine with muscarinic receptors is most likely due to similar shape and surface charge distribution of portions of acetylcholine and the bile acid. We propose that bile acids are signaling molecules whose effects may be mediated by interaction with muscarinic receptors.  相似文献   
58.
59.
The social organization of commercial sex work in Moscow,Russia   总被引:3,自引:0,他引:3  
BACKGROUND: Increased poverty, unemployment, and migration place the Russian population at high risk for sexually transmitted infections (STIs). A qualitative study was undertaken to clarify the organization of sex work and describe the likely contributions of different types of sex work to disease transmission. GOAL: The goal of the study was to describe the social-organizational patterns of sex work in Moscow, Russia. STUDY DESIGN: Four qualitative data collection methods were used: semistructured telephone interviews, semistructured face-to-face individual and group interviews with key informants, systematic and unobtrusive naturalistic observations, and geomapping. RESULTS: Intermittent, truck stop, and railway station sex workers may be the most important groups in the dissemination of STIs. Sex work is widely disseminated throughout the city. Identifiable positions in the social organization of street sex work include pimps, assistant female pimps, guards, drivers, "indicators," the sex workers themselves, and recruitment "pluckers." CONCLUSION: The Moscow sex market may be an adjustive response of the social system to the economic pressures in Russia. Sex work in Moscow has great potential for disseminating STIs throughout Russia and beyond. Understanding of these issues may enhance the impact of STI prevention programs.  相似文献   
60.
OBJECTIVES: There is scarce information on violence against women in the Brazilian society. This fact is rarely reported in medical records as part of the diagnosis and case management, despite evidence showing the significant impact of violence on the population's health. The study aim was to estimate the occurrence of violence against women, and to determine the nature and magnitude of the violent action and the relationship between women and her aggressors. METHODS: The study was conducted among women seen in a primary care unit of the city of S?o Paulo, Brazil, in a two-month period in 1998. The occurrence of violence cases was ascertained using standardized interviews to all women aged 15 to 49 years who sought health care during the study. Three-hundred and twenty-two women were interviewed. RESULTS: Of the participants, 143 (44.4%; IC95%=38.9-49.8%) reported at least one episode of physical violence in their adult life, 110 of those perpetrated by their partners or family members (34.1%; IC95%=28.9-39.3%). Thirty-seven women (11.5%; IC95%=8.0-14.9%) reported at least one episode of sexual violence in their adult life, 23 of those perpetrated by their partners or family members (7.1%; IC95%=4.3-9.9%). CONCLUSIONS: As reported in other countries, physical and sexual violence is highly frequent among women seen in primary care services. In most cases their partners and family members are the perpetrators and the episodes are mostly serious and recurrent.  相似文献   
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