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971.
Most midlife women have hot flashes. The conventional criterion (≥2 μmho rise/30 s) for classifying hot flashes physiologically has shown poor performance. We improved this performance in the laboratory with Support Vector Machines (SVMs), a pattern classification method. We aimed to compare conventional to SVM methods to classify hot flashes in the ambulatory setting. Thirty-one women with hot flashes underwent 24 h of ambulatory sternal skin conductance monitoring. Hot flashes were quantified with conventional (≥2 μmho/30 s) and SVM methods. Conventional methods had low sensitivity (sensitivity=.57, specificity=.98, positive predictive value (PPV)=.91, negative predictive value (NPV)=.90, F1=.60), with performance lower with higher body mass index (BMI). SVMs improved this performance (sensitivity=.87, specificity=.97, PPV=.90, NPV=.96, F1=.88) and reduced BMI variation. SVMs can improve ambulatory physiologic hot flash measures.  相似文献   
972.
The recent identification of Streptococcus pseudopneumoniae (pseudopneumococcus) has complicated classification schemes within members of the "mitis" streptococcal group. Accurate differentiation of this species is necessary for understanding its disease potential and identification in clinical settings. This work described the use of the competence-stimulatory peptide ComC sequence for identification of S. pseudopneumoniae. ComC sequences from clinical sources were determined for 17 strains of S. pseudopneumoniae, Streptococcus pneumoniae, and Streptococcus oralis. An additional 58 ComC sequences from a range of sources were included to understand the diversity and suitability of this protein as a diagnostic marker for species identification. We identified three pherotypes for this species, delineated CSP6.1 (10/14, 79%), CSP6.3 (3/14, 21%), and SK674 (1/14, 7%). Pseudopneumococcal ComC sequences formed a discrete cluster within those of other oral streptococci. This suggests that the comC sequence could be used to identify S. pseudopneumoniae, thus simplifying the study of the pathogenic potential of this organism. To avoid confusion between pneumococcal and pseudopneumococcal pherotypes, we have renamed the competence pherotype CSP6.1, formerly reported as an "atypical" pneumococcus, CSPps1 to reflect its occurrence in S. pseudopneumoniae.  相似文献   
973.
Treatment options for primary and secondary liver tumors that cannot be resected or ablated are based on transarterial techniques. Although the majority of these are based on bland and chemoembolization techniques, yttrium-90 microspheres represent an alternate transarterial option. Although the amount of literature on (90)Y does not rival that of bland or chemoembolization, there nevertheless are ample data that support its use for primary and metastatic liver tumors. A comprehensive review of the entire available literature dating from the early 1960s is presented, as is a discussion of the possibilities for future research with use of radioembolization as a platform.  相似文献   
974.
Laboratory diagnosis of syphilis has undergone major changes in the past decade with the introduction of immunoassays and recombinant Treponema pallidum antigens as screening tools for syphilis infection. To address this change in laboratory practice, a national syphilis laboratory working group was established with members from the Public Health Agency of Canada, provincial public health laboratories across the country as well as sexually transmitted infection researchers, clinicians and epidemiologists. This working group aims to examine how the use of newer immunoassays will affect syphilis diagnosis, surveillance and disease management. To provide a baseline for this work, an e-mail survey was conducted in the fall of 2009 to determine current laboratory practices for syphilis diagnosis in Canada. The most commonly used tests were rapid plasma reagin, enzyme immunoassay, T pallidum passive particle agglutination, venereal disease research laboratory, fluorescent treponemal antibody absorption, line immunoassay and polymerase chain reaction with 92%, 36%, 32%, 20%, 12%, 12% and 12% of the responding laboratories reporting using these tests, respectively. The ultimate goal of this working group will be to update laboratory guidelines for the diagnosis of syphilis, and to identify syphilis surveillance and research priorities in Canada.  相似文献   
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976.
The response of human subconjunctival fibroblasts to a variety of pharmacological agents was evaluated utilizing a novel in vitro wound assay and a separate proliferation assay. Both colchicine and cytochalasin B dramatically arrested wound closure at concentrations greater than or equal to 0.01 micrograms/ml and 2 micrograms/ml, respectively (p less than 0.05). At lower doses these drugs altered fibroblast morphology and inhibited directed cell migration. Dexamethasone and 6-MP delayed wound closure at concentrations greater than or equal to 100 micrograms/ml and 1000 micrograms/ml, respectively (p less than 0.05). Effective antiproliferative agents, in order of decreasing potency (based on unit weight), were Cytarabine (cytosine arabinoside), doxorubicin (Adriamycin), colchicine, 5-fluorouracil, cytochalasin B, cyclosporin (Sandimmune), 6-mercaptopurine, and dexamethasone. The antiprotease agents and methotrexate were ineffective as determined by both assays. We conclude that the wound assay is well suited for rapid screening of drugs for their effect on fibroblast morphology, motility, and proliferation, and that colchicine and cytochalasin B, in doses well below those documented to produce ocular toxicity, are effective in inhibiting directed migration and proliferation of subconjunctival fibroblasts in vitro. Differences in mechanism, onset of action, therapeutic range, and cytotoxicity of drugs could be exploited in controlling ocular fibroblast behavior in vivo.  相似文献   
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