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991.
992.
High levels of in vitro igm rheumatoid factor synthesis correlate with hla–dr4 in normal individuals
Nancy J. Olsen MD Peter Stastny MD Hugo E. Jasin MD 《Arthritis \u0026amp; Rheumatology》1987,30(8):841-848
The association between the HLA–DR4 histocompatibility antigen and in vitro synthesis of IgM and IgM rheumatoid factor (IgM-RF) by blood mononuclear cells was investigated in 35 normal subjects. In vitro cultures of T and B cells were stimulated with pokeweed mitogen, and the secreted IgM-RF, tetanus antibody, and total IgM protein were measured by solid-phase radioimmunoassay. In cultures containing unseparated T cells, IgM-RF production in the DR4+ and DR4–subgroups was not significantly different. However, depletion of OKT8+ cells containing T suppressor cells resulted in significantly higher IgM and IgM-RF synthesis in the DR4+ subgroup. Moreover, 6 of the 8 highest levels of IgM-RF were produced by DR4+ individuals, while only 7 of the remaining 27 individuals were DR4+ (P = 0.035). Ratios of secreted IgM-RF : IgM indicated that there was a relative enrichment for IgM-RF–specific B cell precursors in DR4+ high responders, although total numbers of circulating B cells were not increased. High responder B cells had high levels of responsiveness when mixed with T helper cells from low responders, whereas low responder B cells consistently produced low responses, even when cocultured with T helper cells from high responder donors. The data suggest that a subset of normal individuals has a pokeweed mitogen–responsive lymphocyte population that contains a B cell subpopulation specific for IgM-RF synthesis and that this condition is associated with HLA–DR4. In certain individuals who have the DR4 type, there may be a component of a susceptible genetic background, upon which other factors act to induce IgM-RF synthesis and which may produce clinical manifestations of rheumatoid arthritis. 相似文献
993.
Nancy Winnik Berland J. Kevin Thompson Patrick H. Linton 《The International journal of eating disorders》1986,5(3):569-574
The 40-item Eating Attitudes Jest, the 26-item Eating Attitudes Test, the Restrained Eating Inventory (El), and the Eating Disorders Inventory (EDI) were given to 81 women who were participating in an eating disorders study. The EAT-26 totals and the scores of the three factors were intercorrelated. The scores of the EAT-26 were also correlated with the scores of the EAT-40, and El, and the EDI. The EAT-26 correlated significantly with all three of its factors as well as with the EAT-40. These results suggest that the EAT-26 is a reliable and economical substitute for the EAT-40. The EAT-26 correlates highly with the eight subscales of the EDI and with the El, suggesting concurrent validity. 相似文献
994.
Tim Boogaerts Siel Van den Bogaert Laura A. E. Van Poelvoorde Diala El Masri Naomi De Roeck Nancy H. C. Roosens Marie Lesenfants Lies Lahousse Koenraad Van Hoorde Alexander L. N. van Nuijs Peter Delputte 《Viruses》2022,14(3)
Since the beginning of the COVID-19 pandemic, the wastewater-based epidemiology (WBE) of SARS-CoV-2 has been used as a complementary indicator to follow up on the trends in the COVID-19 spread in Belgium and in many other countries. To further develop the use of WBE, a multiplex digital polymerase chain reaction (dPCR) assay was optimized, validated and applied for the measurement of emerging SARS-CoV-2 variants of concern (VOC) in influent wastewater (IWW) samples. Key mutations were targeted in the different VOC strains, including SΔ69/70 deletion, N501Y, SΔ241 and SΔ157. The presented bioanalytical method was able to distinguish between SARS-CoV-2 RNA originating from the wild-type and B.1.1.7, B.1.351 and B.1.617.2 variants. The dPCR assay proved to be sensitive enough to detect low concentrations of SARS-CoV-2 RNA in IWW since the limit of detection of the different targets ranged between 0.3 and 2.9 copies/µL. This developed WBE approach was applied to IWW samples originating from different Belgian locations and was able to monitor spatio-temporal changes in the presence of targeted VOC strains in the investigated communities. The present dPCR assay developments were realized to bring added-value to the current national WBE of COVID-19 by also having the spatio-temporal proportions of the VoC in presence in the wastewaters. 相似文献
995.
996.
Nancy McKinley 《The Physician and sportsmedicine》2013,41(12):88-89
Sled-skiing is easy to learn and allows individuals with mobility impairments to share the slopes with Alpine skiers. 相似文献
997.
998.
ABSTRACT: The European Network for Breast Development and Cancer (ENBDC) meeting on 'Methods in Mammary Gland Development and Cancer' has become an annual international rendezvous for scientists with interests in the normal and neoplastic breast. The fourth meeting in this series, held in April in Weggis, Switzerland, focused on proteomics, epigenetics, symmetric division, and metastasis. 相似文献
999.
1000.