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41.
This study investigates satisfaction with care among elderly Medicare beneficiaries enrolled in a health maintenance organization (HMO) and beneficiaries in fee-for-service (FFS) care in the same geographic area. Satisfaction with two dimensions of care, access/quality and costs, are examined, to investigate differences in enrollee/FFS evaluation of these dimensions of care as well as predictors of satisfaction with care. In addition, satisfaction among healthy and chronically ill elderly people in these two care settings is explored. Results indicate higher satisfaction with access/quality of care among those in FFS and higher satisfaction with costs among HMO enrollees. These relationships hold controlling for other variables and among the chronically ill elderly. Sources of variation in satisfaction are somewhat different among the HMO and FFS elderly. Satisfaction with paperwork and ease of getting to care, however, influences satisfaction with other aspects of care in both populations. 相似文献
42.
Targeted gene disruption of murine CD7 总被引:2,自引:0,他引:2
CD7 is a 40 kDa type I transmembrane glycoprotein member of the Ig
superfamily. CD7 is a marker of mature human T cells and NK cells, and is
expressed early in their development. Cross-linking CD7 positively
modulates T cell and NK cell activity as measured by calcium fluxes,
expression of adhesion molecules, cytokine secretion and proliferation. CD7
associates directly with phosphoinositol 3'-kinase, and CD7 ligation
induces production of D-3 phosphoinositides and tyrosine phosphorylation.
Severe combined immunodeficiency has been associated with a lack of
lymphocyte surface CD7. The CD7 ligand is unknown. The murine CD7 homolog
is encoded by a single gene on chromosome 11. In order to characterize the
role of CD7 in lymphocyte development and function we have eliminated the
CD7 gene by targeted disruption. CD7- deficient mice display normal
histology of thymus and spleen, normal lymphocyte populations in primary
and secondary lymphoid tissues, and normal serum Ig levels. Specific
antibody responses after immunization with T-dependent and T-independent
antigens are equivalent in wild-type and CD7 knockout mice. CD7-deficient
lymphocytes respond normally to T cell mitogenic and allogeneic stimuli,
and display normal NK cell cytotoxicity.
相似文献
43.
Multiclonal Leishmania braziliensis population structure and its clinical implication in a region of endemicity for American tegumentary leishmaniasis
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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)
Schriefer A Schriefer AL Góes-Neto A Guimarães LH Carvalho LP Almeida RP Machado PR Lessa HA de Jesus AR Riley LW Carvalho EM 《Infection and immunity》2004,72(1):508-514
In Corte de Pedra (CP), northeastern Brazil, Leishmania braziliensis causes three distinct forms of American tegumentary leishmaniasis (ATL). To test the hypothesis that strain polymorphism may be involved in this disease spectrum and accurately characterize the parasite population structure in CP, we compared one L. major, two non-CP L. braziliensis, one CP L. amazonensis, and 45 CP L. braziliensis isolates, obtained over a 10-year period from localized cutaneous, mucosal, and disseminated leishmaniasis patients, with randomly amplified polymorphic DNA (RAPD). Electrophoretic profiles were mostly unique across species. All typing protocols revealed polymorphism among the 45 CP L. braziliensis isolates, which displayed eight different RAPD patterns and greater than 80% overall fingerprint identity, attesting to the adequacy of the tools to assess strain variability in CP's geographically limited population of parasites. The dendrogram based on the sum of RAPD profiles of each isolate unveiled nine discrete typing units clustered into five clades. Global positioning showed extensive overlap of these clades in CP, precluding geographic sequestration as the mechanism of the observed structuralization. Finally, all forms of ATL presented a statistically significant difference in their frequencies among the clades, suggesting that L. braziliensis genotypes may be accompanied by specific disease manifestation after infection. 相似文献
44.
Serodiagnosis of Helicobacter hepaticus infection in mice by an enzyme-linked immunosorbent assay. 总被引:2,自引:0,他引:2
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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)
R S Livingston L K Riley E K Steffen C L Besch-Williford R R Hook Jr C L Franklin 《Journal of clinical microbiology》1997,35(5):1236-1238
Helicobacter hepaticus is a newly recognized bacterium associated with chronic active hepatitis, hepatic carcinoma, and inflammatory bowel disease in mice. Currently, fecal or tissue PCR, fecal culture, or histologic examination of silver-stained liver sections is used to diagnose H. hepaticus infection. In this report, we describe an enzyme-linked immunosorbent assay (ELISA) for serodiagnosis of H. hepaticus infection in mice with a membrane digest preparation of H. hepaticus as the antigen. Sera from mice positive for H. hepaticus by PCR or histologic examination (n = 88), positive for Helicobacter bilis by PCR (n = 13), positive for other helicobacters (not identifiable to species level) by PCR (n = 25), or negative for all Helicobacter species by PCR (n = 162) were used to evaluate the ELISA. Results indicated that ELISA provided 93.2% sensitivity, 94% specificity, 87.2% positive predictive value, and 96.9% negative predictive value. Cross-reactive antibodies were detected in some mice infected with helicobacters not identifiable to species level. To further define ELISA sensitivity and specificity, groups of 10 C57BL/6 mice were inoculated per os with H. hepaticus, Helicobacter muridarum, or H. bilis. Sera were collected and examined by the ELISA. H. hepaticus-infected mice seroconverted by 2 weeks and maintained ELISA reactivity throughout the 18-week study, while mice infected with H. muridarum and H. bilis were negative by ELISA. These results indicate that this reported ELISA is highly sensitive and specific for the serodiagnosis of H. hepaticus infection in mice. 相似文献
45.
The Benzodiazepine Withdrawal Symptom Questionnaire 总被引:5,自引:0,他引:5
A self-report questionnaire is described which records the main symptoms experienced during withdrawal from benzodiazepines in pharmacologically dependent patients. The questionnaire consists of 20 items; evidence is given that these are reasonably independent and are sensitive in detecting withdrawal symptoms from a study of 68 patients undergoing slow withdrawal from benzodiazepines. 相似文献
46.
Franks S Baton L Tetteh K Tongren E Dewin D Akanmori BD Koram KA Ranford-Cartwright L Riley EM 《Infection and immunity》2003,71(6):3485-3495
Diversity in the surface antigens of malaria parasites is generally assumed to be a mechanism for immune evasion, but there is little direct evidence that this leads to evasion of protective immunity. Here we show that alleles of the highly polymorphic merozoite surface protein 2 (MSP-2) can be grouped (within the known dimorphic families) into distinct serogroups; variants within a serogroup show extensive serological cross-reactivity. Cross-reactive epitopes are immunodominant, and responses to them may be boosted at the expense of responses to novel epitopes (original antigenic sin). The data imply that immune selection explains only some of the diversity in the msp-2 gene and that MSP-2 vaccines may need to include only a subset of the known variants in order to induce pan-reactive antibodies. 相似文献
47.
Astrid LA. Kuijpers Rolph Pfundt Patrick LJM Zeeuwen Henri OF. Molhuizen Edwin CM. Mariman Peter CM. van de Kerkhof Joost Schalkwijk 《Clinical genetics》1998,54(1):96-101
Psoriasis is a multifactorial skin disease characterised by epidermal abnormalities and infiltration by lymphocytes and polymorphonuclear leukocytes (PMN). Skin-derived antileukoproteinase (SKALP), also known as elafin, is a potent inhibitor of human leukocyte elastase and proteinase 3, two PMN-derived proteinases implicated in tissue destruction and leukocyte migration. We have shown that, at least at the protein level, SKALP is significantly decreased in lesional skin of patients with pustular psoriasis compared with plaque-type psoriasis. This finding raised the possibility that SKALP could be one of the candidate genes for pustular forms of psoriasis. We therefore performed single strand conformation polymorphism (SSCP) analysis on the SKALP gene to screen for mutations/polymorphisms in the exons of 30 patients with plaque-type psoriasis, 15 patients with pustular psoriasis and 48 healthy controls. In exon 1 a polymorphism was detected at position + 43 relative to the translation start site, resulting in a substitution of threonine for alanine in the signal peptide. In the promoter region a dinucleotide repeat polymorphism was identified. Both polymorphisms were not associated with pustular psoriasis, or psoriasis in general. Our data indicate that the decrease in SKALP activity in pustular psoriasis is not caused by mutations in the coding region of the gene, and that there is no allelic association between pustular psoriasis and SKALP gene polymorphisms. 相似文献
48.
Analysis of two IL-4 promoter polymorphisms in a cohort of atopic and asthmatic subjects 总被引:2,自引:0,他引:2
Hook S Cheng P Holloway J Riley G Sawyer G Le Gros G Beasley R 《Experimental and clinical immunogenetics》1999,16(1):33-35
The Th2 cytokine interleukin 4 (IL-4) has been identified as having a central role in driving the inflammatory immune responses which are present in atopic airway disease. This study examined the distribution of two putative IL-4 promoter polymorphisms (-285 C-T and -81 A-G) in groups of patients with severe and moderate asthma, non-asthmatic atopy and control subjects. Neither polymorphism was identified in any of the samples tested. The data suggest that either the polymorphisms are present at very low frequencies or are artefacts of the B cell lines from which they were identified. 相似文献
49.
Upregulation of TGF-beta, FOXP3, and CD4+CD25+ regulatory T cells correlates with more rapid parasite growth in human malaria infection 总被引:8,自引:0,他引:8
Walther M Tongren JE Andrews L Korbel D King E Fletcher H Andersen RF Bejon P Thompson F Dunachie SJ Edele F de Souza JB Sinden RE Gilbert SC Riley EM Hill AV 《Immunity》2005,23(3):287-296
Understanding the regulation of immune responses is central for control of autoimmune and infectious disease. In murine models of autoimmunity and chronic inflammatory disease, potent regulatory T lymphocytes have recently been characterized. Despite an explosion of interest in these cells, their relevance to human disease has been uncertain. In a longitudinal study of malaria sporozoite infection via the natural route, we provide evidence that regulatory T cells have modifying effects on blood-stage infection in vivo in humans. Cells with the characteristics of regulatory T cells are rapidly induced following blood-stage infection and are associated with a burst of TGF-beta production, decreased proinflammatory cytokine production, and decreased antigen-specific immune responses. Both the production of TGF-beta and the presence of CD4+CD25+FOXP3+ regulatory T cells are associated with higher rates of parasite growth in vivo. P. falciparum-mediated induction of regulatory T cells may represent a parasite-specific virulence factor. 相似文献
50.
Helicobacter hepaticus causes disease in the liver and lower intestinal tract of mice. It is strongly urease positive, although it does not live in an acidic environment. The H. hepaticus urease gene cluster was expressed in Escherichia coli with and without coexpression of the Helicobacter pylori nickel transporter NixA. As for H. pylori, it was difficult to obtain enzymatic activity from recombinant H. hepaticus urease; special conditions including NiCl2 supplementation were required. The H. hepaticus urease cluster contains a homolog of each gene in the H. pylori urease cluster, including the urea transporter gene ureI. Downstream genes were homologs of the nik nickel transport operon of E. coli. Nongastric H. hepaticus produces urease similar to that of H. pylori. 相似文献