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111.
Increased Sensitivity of a New Coagglutination Test for Rapid Identification of Haemophilus influenzae Type b
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Robert J. Grasso Loyd A. West Nikki J. Holbrook Demetrios G. Halkias Lois J. Paradise Herman Friedman 《Journal of clinical microbiology》1981,13(6):1122-1124
A newly developed rapid coagglutination test for identifying Haemophilus influenzae type b organisms isolated from clinical specimens correlated 100% with the slide agglutination test but was 100- to 200-fold more sensitive. 相似文献
112.
Seventy-four mothers and 41 fathers and their 6 to 13 year old sons with attention-deficit hyperactivity disorder (ADHD) watched videos of child ADHD symptoms, compliance, and noncompliance. Participants were told either that the child was receiving medication, behavioral treatment, a combination of the two, or was not receiving treatment and were asked to rate the cause of the behavior. Parents attributed less control but greater stability to positive child behaviors when the child was receiving medication. However, for negative behaviors, medication increased attributions of control but diminished stability. With behavior management. compliance was seen as more external and stable and noncompliance as more controllable but less stable. For all treatments, boys reported increased control over ADHD symptoms and noncompliance. The implications of these treatment-related attributions for parenting and children's self-perceptions are discussed. 相似文献
113.
Lawrence S. Webb Bernard B. Keele Jr. Richard B. Johnston Jr. 《Infection and immunity》1974,9(6):1051-1056
During the process of phagocytosis, human leukocytes emit a burst of luminescence which can be measured in a liquid scintillation spectrometer. The enzyme superoxide dismutase, which removes superoxide anions (O(2.)), inhibited this chemiluminescence by 70% at a concentration of 100 mug/ml. The enzyme did not inhibit phagocytosis. These results support other studies indicating that O(2.) is elaborated by phagocytizing leukocytes. They also indicate that O(2.) plays a major role in phagocytosis-associated chemiluminescence, though not necessarily as the luminescing agent. Catalase and benzoate inhibited the chemiluminescence of phagocytosis to a slight extent, suggesting that hydrogen peroxide and hydroxyl radical, respectively, might also be involved in this phenomenon. The relationship between the mediators of chemiluminescence and those responsible for phagocytic bactericidal activity remains to be defined. 相似文献
114.
Synergy between the genes for butyrylcholinesterase K variant and apolipoprotein E4 in late-onset confirmed Alzheimer's disease 总被引:5,自引:2,他引:5
The allelic frequency of the gene for the K variant of
butyrylcholinesterase (BCHE-K) was 0.17 in 74 subjects with late-onset (age
> 65 years) histopathologically diagnosed Alzheimer's disease (AD),
which was higher than the frequencies in 104 elderly control subjects
(0.09), in 14 early-onset cases of confirmed AD (0.07) and in 29 confirmed
cases of other dementia (0.10). The association of BCHE-K with late-onset
AD was limited to carriers of the epsilon 4 allele of the apolipoprotein E
gene (APOE), among whom the presence of BCHE-K gave an odds ratio of
confirmed late-onset AD of 6.9 (95% C.I. 1.65-29) in subjects > 65 years
and of 12.8 (1.9-86) in subjects > 75 years. In APOE epsilon 4 carriers
over 75 years, only 1/22 controls, compared with 10/24 confirmed late-onset
AD cases, had BCHE-K. We suggest that BCHE-K, or a nearby gene on
chromosome 3, acts in synergy with APOE epsilon 4 as a susceptibility gene
for late-onset AD.
相似文献
115.
Immunochemical analysis of immune response to Chlamydia trachomatis in Reiter''s syndrome and nonspecific urethritis. 总被引:6,自引:0,他引:6
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R D Inman M E Johnston B Chiu J Falk M Petric 《Clinical and experimental immunology》1987,69(2):246-254
Chlamydia trachomatis (Ct) has been proposed as a causative agent in Reiter's syndrome (RS) when an infection occurs in a susceptible host. To assess whether this susceptibility is reflected in a characteristic humoral immune response we compared patients with complicated (RS) and uncomplicated courses of nonspecific urethritis (NSU). Geometric mean titres of antibodies to C. trachomatis by immunofluorescence were 89.6 for RS, 80.0 for NSU and 16.0 for normals. 125I-Protein A probing of immunoblotted antigens of C. trachomatis revealed no band unique to RS. 125I-anti-IgA probing of immunoblots demonstrated reactivity with the 59,000 dalton antigen in 11/11 RS and 2/6 NSU. The major outer membrane protein of C. trachomatis (40,000 daltons) bound immunoglobulin nonspecifically. There was no clearly differentiating feature between HLA-B27-positive and B27-negative RS. One sequentially studied patient revealed an augmentation in synovial fluid IgA reactivity during the course of disease. No pattern of humoral immune response to C. trachomatis could be regarded as specific for RS nor for HLA B27-positivity. The study did not identify a Reiter's-specific antigen in C. trachomatis but demonstrates the usefulness of applying blotting techniques to population studies of HLA modulation of immune response to infectious agents. 相似文献
116.
117.
118.
Torous DK Hall NE Illi-Love AH Diehl MS Cederbrant K Sandelin K Pontén I Bolcsfoldi G Ferguson LR Pearson A Majeska JB Tarca JP Hynes GM Lynch AM McNamee JP Bellier PV Parenteau M Blakey D Bayley J van der Leede BJ Vanparys P Harbach PR Zhao S Filipunas AL Johnson CW Tometsko CR Dertinger SD 《Environmental and molecular mutagenesis》2005,45(1):44-55
An interlaboratory study was performed to validate an anti-CD71/flow cytometry-based technique for enumerating micronucleated reticulocytes (MN-RETs) in mouse peripheral blood. These experiments were designed to address International Workshop on Genotoxicity Test Procedures validation criteria by evaluating the degree of correspondence between MN-RET measurements generated by flow cytometry (FCM) with those obtained using traditional microscopy-based methods. In addition to these cross-methods data, flow cytometric MN-RET measurements for each blood sample were performed at two separate sites in order to evaluate the reproducibility of data between laboratories. In these studies, groups of male CD-1 mice were treated with vehicle (saline or vegetable oil), a negative control (saline or vegetable oil), or four dose levels of five known genotoxicants (clastogens: cyclophosphamide, benzo[a]pyrene, 5-fluorouracil, methotrexate; aneugen: vincristine sulfate). Exposure occurred on 3 consecutive days via intraperitoneal injection, and blood samples were obtained approximately 24 hr after the final treatment. MN-RET frequencies were determined for each sample based on the analysis of 2,000 (microscopy) and 20,000 (FCM) reticulocytes. Regardless of the method utilized, each genotoxic agent was observed to cause statistically significant increases in the frequency of MN-RETs, and each response occurred in a dose-dependent manner. Spearman's correlation coefficient (rs) for FCM versus microscopy-based MN-RET measurements (nine experiments, 252 paired measurements) was 0.740, indicating a high degree of correspondence between methods. The rs value for all flow cytometric MN-RET measurements performed at the two independent sites was 0.857 (n = 248), suggesting that the automated method is highly transferable between laboratories. Additionally, the flow cytometric system offered advantages relative to microscopy-based scoring, including a greater number of cells analyzed, much faster analysis times, and a greater degree of objectivity. Collectively, data presented in this report suggest that the overall performance of mouse peripheral blood micronucleus tests is enhanced by the use of the flow cytometric scoring procedure. 相似文献
119.
Cindy Johnston Stephan Eliez Jennifer Dyer‐Friedman David Hessl Bronwyn Glaser Christine Blasey Annette Taylor Allan Reiss 《American journal of medical genetics. Part A》2001,103(4):314-319
There have been contradictory findings in the fragile X (fraX) literature about possible neurocognitive and psychological symptoms due to the fraX premutation (pM). The purpose of the present study was to investigate the relationship between CGG repeat length and neurobehavioral functioning in carriers of the fraX pM. Eighty‐five female carriers of the pM with allele sizes ranging from 59–166 were administered a comprehensive IQ test (WAIS‐III) and completed a questionnaire designed to measure psychopathology (Symptom Checklist (SCL)‐90‐R). No relationship between allele size and cognition was identified. A significant negative relationship between allele size and age was found, as well as a positive relationship between allele size and depression. Follow‐up analyses separating small and large allele sizes (below and above 100 CGG repeats) indicated that individuals with larger allele sizes scored significantly higher on the Interpersonal Sensitivity and Depression subscales of the SCL‐90‐R. Despite the limitation of few individuals with high CGG repeat lengths, our findings suggest that females with larger premutated alleles (≥ 100 repeats) display some clinical manifestations of fraX syndrome. © 2001 Wiley‐Liss, Inc. 相似文献
120.
Cholinergic, serotoninergic and neuropeptidergic components of the nervous system were examined and compared in the progenetic metacercaria and adult gasterostome trematode, Bucephaloides gracilescens in order to provide baseline information on neuronal control of the musculature involved in egg-assembly. Enzyme cytochemistry and indirect immunocytochemical techniques interfaced with confocal scanning laser microscopy demonstrated all three classes of neuroactive substance throughout the central and peripheral nervous systems. A comparable orthogonal arrangement of the central nervous system (CNS) and peripheral array of nerve plexuses was observed in both metacercaria and adult. Staining patterns for cholinergic and peptidergic substances showed significant overlap, while the serotoninergic system was confined to a separate set of neurons. Immunostaining for FMRFamide-related peptides (FaRPs) was strong in the CNS and peripheral innervation to the attachment apparatus of metacercaria and adult but was only found in the innervation of the ootype in ovigerous adults, implicating FaRPs in neuronal control of the muscle of the female reproductive tract during egg-assembly. 相似文献