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101.
Mendonça EA Haas J Shagina L Larson E Friedman C 《Journal of biomedical informatics》2005,38(4):314-321
Natural language processing (NLP) is critical for improvement of the healthcare process because it can encode clinical data in patient documents. Many clinical applications such as decision support require coded data to function appropriately. However, in order to be applicable for healthcare, performance must be adequate. A valuable automated application is the detection of infectious diseases, such as surveillance of pneumonia in newborns (e.g., neonates) because the disease produces significant rates of morbidity and mortality, and manual surveillance is challenging. Studies have demonstrated that automated surveillance using NLP is a useful adjunct to manual surveillance and an effective tool for infection control practitioners. This paper presents a study evaluating the feasibility of an NLP-based monitoring system to screen for healthcare-associated pneumonia in neonates. We estimated sensitivity, specificity, and positive predictive value by comparing results with clinicians' judgments. Sensitivity was 71% and specificity was 99%. Our results demonstrated that the automated method was feasible. 相似文献
102.
Molecular epidemiology of macrolide resistance in neonatal bloodstream isolates of group B streptococci 总被引:6,自引:0,他引:6
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![点击此处可从《Journal of clinical microbiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Diekema DJ Andrews JI Huynh H Rhomberg PR Doktor SR Beyer J Shortridge VD Flamm RK Jones RN Pfaller MA 《Journal of clinical microbiology》2003,41(6):2659-2661
Pulsed-field gel electrophoresis (PFGE) was performed on 122 neonatal bloodstream isolates of group B streptococci (GBS) to further examine the relationship between macrolide resistance and serotype V GBS (GBS-V). Over one-third (35%) of macrolide-resistant GBS belonged to a single PFGE subtype of GBS-V, which was also the most common GBS-V subtype noted in previous Centers for Disease Control and Prevention surveillance studies. Erm methylase (ermA and ermB) was the most common resistance mechanism detected, present in 12 of 20 macrolide-resistant GBS. 相似文献
103.
Mechanisms of nitric oxide interplay with Rho GTPase family members in modulation of actin membrane dynamics in pericytes and fibroblasts
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![点击此处可从《The American journal of pathology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Lee JS Kang Decker N Chatterjee S Yao J Friedman S Shah V 《The American journal of pathology》2005,166(6):1861-1870
Migration of pericytes such as hepatic stellate cells is fundamentally important for diverse biological and pathological processes including tumor invasion and fibrosis. In prototypical migratory cells such as fibroblasts, the small GTPases Rac1 and RhoA govern the assembly of lamellipodia and stress fibers, respectively, cytoskeletal structures that are integral to the cell migration process. The gaseous signaling molecule nitric oxide (NO) influences growth factor chemotactic responses, although this occurs primarily in cell-type-specific ways and through cell biological effects that are poorly characterized. In this study, we use complementary molecular and cell biological approaches to delineate important roles for Rac1, RhoA, and NO in migration of the human hepatic stellate cell line LX2 and primary rat hepatic stellate cells. Both platelet-derived growth factor (PDGF) and Rac1 overexpression drove migration through formation of actin-positive filopodia spikes in LX2 as compared to the formation of lamellipodia in fibroblasts. NO inhibited PDGF- and Rac1-driven migration in LX2 by abrogating filopodia formation and inhibited migration of fibroblasts by attenuating lamellipodial protrusions. Additionally, RhoA conferred resistance to NO inhibition of migration and restored chemotactic responses to PDGF in the absence of functional Rac1 in LX2. In conclusion, these studies identify novel crosstalk between small GTPases, cytoskeletal structures, and NO in pericyte-specific pathways, providing counterbalances in the chemotactic responses to growth factors. 相似文献
104.
The potentiating effect of rheumatoid arthritis serum in the immediate phase of nephrotoxic nephritis 总被引:4,自引:4,他引:4
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![点击此处可从《Clinical and experimental immunology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
J. N. McCormick Janet Day C. J. Morris A. G. S. Hill 《Clinical and experimental immunology》1969,4(1):17-28
Nephrotoxic nephritis induced in rats was employed as an experimental model to investigate the possible effects of rheumatoid factor on in vivo antigen–antibody reactions. Rats injected simultaneously with rheumatoid arthritis serum and rabbit nephrotoxic globulin showed a three-fold increase in immediate proteinuria compared with rats injected with nephrotoxic globulin alone. This potentiating effect of rheumatoid arthritis serum was evident even when the serum was injected 48 hr after the nephrotoxic globulin and was also apparent to a lesser extent in rats decomplemented by a prior injection of aggregated human IgG. Normal human serum had no effect on the proteinuria produced by a standard dose of nephrotoxic globulin while rheumatoid arthritis serum injected with normal rabbit globulin did not increase urinary protein excretion above baseline levels. In rats injected with rheumatoid arthritis serum and nephrotoxic globulin, human IgM (presumably rheumatoid factor) was detected by immunofluorescence on the glomerular basement membrane along with the nephrotoxic globulin and rat complement and persisted at this site for as long as 42 days after the initial injections. Rheumatoid factor activity was also recovered by elution from glomeruli isolated from rat kidneys 24 hr after the injection of rheumatoid arthritis serum and nephrotoxic globulin. 相似文献
105.
Caryn Lerman Janet Seay Andrew Balshem Janet Audrain 《American journal of medical genetics. Part A》1995,57(3):385-392
The recent cloning of a breast-ovarian cancer susceptibility gene (BRCA1), and determination of the locus of a related gene (BRCA2), offers potential for clinical genetic testing for breast cancer susceptibility. This study examined interest in and expectations about an impending genetic test among first-degree relatives (FDRs) of breast cancer patients. One hundred five females completed two structured telephone interviews to assess demographics, breast cancer risk factors, psychological factors, and attitudes about genetic testing for breast cancer susceptibility. Overall, 91% of FDRs said that they would want to be tested, 4% said they would not, and 5% were uncertain. The most commonly cited reasons for wanting genetic testing were to learn about one's children's risk, to increase use of cancer screening tests, and to take better care of oneself. Women with less formal education were motivated by childbearing decisions and future planning to a greater degree than were women with education beyond high school. Most women anticipated a negative psychological impact of positive test results, involving increased anxiety (83%), depression (80%), and impaired quality of life (46%). In addition, 72% of women indicated that they would still worry if they tested negative. In multivariate regression analysis, level of baseline depression was the strongest predictor of an anticipated negative impact of genetic testing (Beta =.15; P,.0001). These results suggest that the demand for genetic testing for breast cancer susceptibility may be great, even among women who are not likely to have predisposing mutations. Prior to widespread availability of such testing, it will be critical to develop informed consent protocols to educate individuals about the benefits and limitations of predictive testing for this multifactorial disease. © 1995 Wiley-Liss, Inc. 相似文献
106.
A method is described for the assay of isoniazid in serum and other fluids by diffusion along slopes of Löwenstein-Jensen medium inoculated with tubercle bacilli. The method is convenient, rapid and robust, but is less accurate than diffusion systems for the assay of some other substances. 相似文献
107.
108.
Characterization of CD8+ T cells and microenvironment in oral lesions of human immunodeficiency virus-infected persons with oropharyngeal candidiasis
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![点击此处可从《Infection and immunity》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Oropharyngeal candidiasis (OPC), the most common oral infection in human immunodeficiency virus-positive persons, correlates with reduced blood CD4+ T cells. In those with OPC, CD8+ T cells accumulate at the lamina propria-epithelium interface at a distance from the organism at the outer epithelium. The present study aimed to characterize the tissue-associated CD8+ T cells and tissue microenvironment in both OPC+ and OPC- persons. The results show that the majority of CD8+ T cells possess the alphabeta T-cell receptor, the thymus-derived alphabeta CD8 antigen heterodimer, and similar levels of the alpha(4)beta(7), alpha(4)beta(1), and alpha(e)beta(7) homing receptors. Studies to evaluate the tissue microenvironment showed that in OPC+ persons, the adhesion molecule for T cells to enter mucosa, mucosal addressin cell adhesion molecule, is significantly increased, whereas E-cadherin, which allows T cells to migrate through mucosa, is significantly decreased compared to OPC- persons. These results continue to support a role for CD8+ T cells against OPC under conditions of reduced numbers of CD4+T cells, with susceptibility to infection potentially associated with a dysfunction in mucosal CD8+ T-cell migration by reduced tissue-associated E-cadherin. 相似文献
109.
The PHQ-15: validity of a new measure for evaluating the severity of somatic symptoms 总被引:1,自引:0,他引:1
OBJECTIVE: Somatization is prevalent in primary care and is associated with substantial functional impairment and healthcare utilization. However, instruments for identifying and monitoring somatic symptoms are few in number and not widely used. Therefore, we examined the validity of a brief measure of the severity of somatic symptoms. METHODS: The Patient Health Questionnaire (PHQ) is a self-administered version of the PRIME-MD diagnostic instrument for common mental disorders. The PHQ-15 comprises 15 somatic symptoms from the PHQ, each symptom scored from 0 ("not bothered at all") to 2 ("bothered a lot"). The PHQ-15 was administered to 6000 patients in eight general internal medicine and family practice clinics and seven obstetrics-gynecology clinics. Outcomes included functional status as assessed by the 20-item Short-Form General Health Survey (SF-20), self-reported sick days and clinic visits, and symptom-related difficulty. RESULTS: As PHQ-15 somatic symptom severity increased, there was a substantial stepwise decrement in functional status on all six SF-20 subscales. Also, symptom-related difficulty, sick days, and healthcare utilization increased. PHQ-15 scores of 5, 10, 15, represented cutoff points for low, medium, and high somatic symptom severity, respectively. Somatic and depressive symptom severity had differential effects on outcomes. Results were similar in the primary care and obstetrics-gynecology samples. CONCLUSIONS: The PHQ-15 is a brief, self-administered questionnaire that may be useful in screening for somatization and in monitoring somatic symptom severity in clinical practice and research. 相似文献
110.