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We have developed a sandwich-type ELISA system for measuring total IgD levels in the serum of atopics and non-atopic controls. In this ELISA system, affinity purified goat anti-human IgD was used for capture. Results were superior to those obtained with monoclonal anti-human IgD antibody. No cross-reactivity could be demonstrated to IgG, IgM, IgA or IgE. The assay showed minimal non-specific binding even with initial serum dilutions of 1:2. The results obtained were reproducible among replicates (Mean CV +/- SEM = 0.03 +/- 0.002; n = 251), between dilutions (CV = 0.08 +/- 0.006; n = 108), and between assays (CV = 0.05 +/- 0.12; n = 5). We used routine radioimmunoassay for measuring total serum IgE. Using these assays total serum IgD and IgE levels were measured in 75 atopic patients and 33 normal subjects. None of the atopics had recent immunotherapy. As expected, the geometric mean serum IgE in atopics (373 ng/ml) was significantly higher than that in normal subjects (49 ng/ml) (P less than 0.01). However, geometric mean serum IgD was also significantly higher in atopics (20.3 micrograms/ml) than that in normal subjects (8.4 micrograms/ml) (P less than 0.02). In both atopic and normal groups, mean serum IgD level did not differ significantly on the bases of age, sex or asthmatic status. Furthermore, total serum IgD was not significantly correlated with total serum IgE (r = 0.14; P = 0.14; n = 108), indicating that immunoregulatory control of the basal levels of the two isotypes is not linked.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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An RNA-binding motif (RBM) gene family has been identified on the human Y chromosome that maps to the same deletion interval as the 'azoospermia factor' (AZF). We have identified the homologous gene family (Rbm) on the mouse Y with a view to investigating the proposal that this gene family plays a role in spermatogenesis. At least 25 and probably >50 copies of Rbm are present on the mouse Y chromosome short arm located between Sry and the centromere. As in the human, a role in spermatogenesis is indicated by a germ cell-specific pattern of expression in the testis, but there are distinct differences in the pattern of expression between the two species. Mice carrying the deletion Yd1, that maps to the proximal Y short arm, are female due to a position effect resulting in non-expression of Sry ; sex-reversing such mice with an Sry transgene produces males with a high incidence of abnormal sperm, making this the third deletion interval on the mouse Y that affects some aspect of spermatogenesis. Most of the copies of Rbm map to this deletion interval, and the Yd1males have markedly reduced Rbm expression, suggesting that RBM deficiency may be responsible for, or contribute to, the abnormal sperm development. In man, deletion of the functional copies of RBM is associated with meiotic arrest rather than sperm anomalies; however, the different effects of deletion are consistent with the differences in expression between the two species.   相似文献   
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A sample of 82 delinquent boys in two institutions and a matched sample of 82 nondelinquent boys from three secondary schools ranked values from the Rokeach Value Survey in their order of importance for self, mother and father. Order of rankings was counter-balanced. Results indicated that the sets of rankings (value systems) were more discrepant between boys and their parents and between the parents themselves in the delinquent sample than in the non-delinquent sample, but only in regard to the set of terminal values. Marked differences in the relative importance of particular values occurred between the two groups both in relation to rankings for self and for parents, and (for both groups) between the boys and their parents (generational) and between mother and father (parental). Favourability towards father correlated positively with degree of value similarity between sons and fathers but only for the terminal values.  相似文献   
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Heart rate reactivity to mental stress is substantially blunted early after heart transplantation, suggesting that the loss of neural modulation limits the cardiovascular response to mental stress. We tested whether reactivity to mental stress recovers during the first year after heart transplantation. Hemodynamic and respiratory responses to mental arithmetic challenge were studied in 20 heart transplant recipients 3, 6, and 12 months after surgery. A normal comparison group was studied at equivalent intervals. Heart rate reactivity to mental arithmetic was significantly reduced in the cardiac transplant group compared to the normal subjects. This effect persisted up to 1 year after transplantation. Heart period variability in the heart transplant recipients was minimal in all three-test sessions. The findings suggest that no functional reinnervation or other compensatory adaptation occurs up to 1 year after heart transplantation.  相似文献   
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IgG antibody to gE, the Fc gamma-binding herpes simplex 1 (HSV-1) viral glycoprotein, was studied in 49 rheumatoid arthritis (RA) patients and 43 normal controls. Antibody to gD, another important HSV-1 antigen, was assayed in parallel. No difference between RA patients and normal controls was found in levels of anti-gE antibody measured by reactivity of IgG F(ab')2 fragments reacting with gE coated to ELISA plates. No difference in anti-gD antibody was recorded between normals and patients with RA. Levels of IgG anti-IgE antibody did not correlate with quantitative elevations of serum rheumatoid factor (RF) in RA patients. When IgG anti-gE and anti-gD were assayed in 20 patients with juvenile rheumatoid arthritis and 22 children controls, no significant differences were noted. However, when individual RFs from patients with RA were tested for reactivity against a panel of affinity-isolated F(ab')2 antibodies to gE, some evidence for individual autospecificity was obtained. Four of 20 monoclonal IgM RFs produced from RA patients' B cells showed marked elevations of reactivity with some RA patients' F(ab')2 antibodies to gE. All four of the monoclonal RFs showing this specificity were derived from RA synovial tissue B cells. These findings may provide support for the concept that some RFs in patients with RA show individual specificity for internal image determinants of IgG antibodies to viral Fc gamma-binding proteins.  相似文献   
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Candida dubliniensis is an opportunistic fungal pathogen that has been linked to oral candidiasis in AIDS patients, although it has recently been isolated from other body sites. DNA sequence analysis of the internal transcribed spacer 2 (ITS2) region of rRNA genes from reference Candida strains was used to develop molecular beacon probes for rapid, high-fidelity identification of C. dubliniensis as well as C. albicans. Molecular beacons are small nucleic acid hairpin probes that brightly fluoresce when they are bound to their targets and have a significant advantage over conventional nucleic acid probes because they exhibit a higher degree of specificity with better signal-to-noise ratios. When applied to an unknown collection of 23 strains that largely contained C. albicans and a smaller amount of C. dubliniensis, the species-specific probes were 100% accurate in identifying both species following PCR amplification of the ITS2 region. The results obtained with the molecular beacons were independently verified by random amplified polymorphic DNA analysis-based genotyping and by restriction enzyme analysis with enzymes BsmAI and NspBII, which cleave recognition sequences within the ITS2 regions of C. dubliniensis and C. albicans, respectively. Molecular beacons are promising new probes for the rapid detection of Candida species.  相似文献   
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