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Laying hens are very efficient producers of antibodies and provide an interesting alternative for large-scale production of specific antibodies. These antibodies also have biochemical advantages over mammalian antibodies (e.g. rabbit antibodies) that can be used to improve immunoassays where antibodies are used. The concentration of IgY in egg yolk is an important production parameter. The purpose of this study was to investigate the genetic variation of IgY levels in egg yolk. We have compared IgY concentrations in egg yolks from two lines, selected for egg production traits at the Swedish University for Agricultural Sciences (Single Comb White Leghorn and Rhode Island Red) and a cross between the two lines (SLU-1392). Single Comb White Leghorns have the highest mean concentration of yolk IgY, 2.21 mg ml-1 compared to SLU-1392 1.95 mg ml-1 and Rhode Island Red 1.68 mg ml-1. The cross thus had an intermediate IgY concentration in relation two the two other lines. There were great differences between individual animals within each line. Our results indicate that it should be possible to increase yolk antibody production by using a high producing chicken line and by genetic selection within the line. We found three individuals with very low yolk IgY concentrations among the Rhode Island Red hens. Newly hatched chickens with limited amounts of IgY from the hen may be more susceptible to infections.  相似文献   
104.
Renal transplant recipients treated with cyclosporine (CS) have been reported to be at increased risk of thrombotic complications. The present study was intended to examine the blood coagulation, fibrinolytic, and inhibitory systems in such patients. Eight transplant recipients on maintenance immunosuppression with CS and prednisone were studied. Five transplant recipients maintained on azathioprine (AZA) and prednisone and 32 normal volunteers served as controls. Plasma antigen concentrations and/or activities of various proteins in the above pathways were measured. Both the CS and AZA groups exhibited significant elevations of factor IX activity, von Willebrand factor (vWF), D-dimer, protein C and tissue type plasminogen activator (t-PA) levels when compared with the normal controls. In addition, CS group showed a significant elevation of alpha 2-macroglobulin activity and AZA group showed a significant reduction in factor XII activity when compared with the normal controls. Comparison of data from CS and AZA groups revealed higher factor XII activity and vWF concentration in the former group. In conclusion, transplant recipients treated with long-term cyclosporine and prednisone exhibited significant elevation of plasma vWF, D-dimer and protein C concentrations. In addition, both CS and AZA-treated transplant recipients showed increased plasma concentrations of D-dimer and t-PA. The latter observations suggest in vivo thrombin generation, fibrin formation and degradation.  相似文献   
105.
Alex  Neil 《JAMA》2004,291(24):3017
  相似文献   
106.
OBJECTIVE: To assess the effectiveness of enriched intervention (EI) on symptomatic and functional outcomes, compared with standard care (SC). METHOD: Studies were retrieved from search engines and, using a metaanalytic approach, we compared El trials with SC trials. Eleven EI sample trials (1053 patients) and 6 SC sample trials (500 patients), totalling data from 1553 patients (69% male), were examined. We calculated the effect sizes (ESs) of both symptomatic and functional improvement over a follow-up period of about 1 year. RESULTS: Significant differences between El and SC were observed at follow-up for the improvement of both positive and negative symptoms, respectively: positive, EI = -1.54 (95%CI, -1.63 to -1.45 ) and SC = -1.07 (95%CI, -1.19 to -0.94) (Qbetween = 40.3, df 1, P < 0.001); negative, EI= -0.44 (95%CI, -0.53 to -0.35) and SC = -0.18 (95%Cl, -0.31 to -0.05) (Qbetween = 10.6, df 1, P < 0.01). We also observed a significant difference between the El and the SC groups for functional improvement over the follow-up period with mean EI = 1.11 (95%CI, 0.99 to 1.23) and SC = 0.63 (95%CI, 0.49 to 0.77) (Qbetween = 24.5, df 1, P < 0.001). CONCLUSIONS: There is now quantitative evidence across multiple studies and sites to indicate that Els for patients with recent-onset psychosis are significantly more effective than SC for symptomatic and functional improvement over a period of about 1 year.  相似文献   
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108.
Human bites. Guidelines for prompt evaluation and treatment   总被引:1,自引:0,他引:1  
Human bites are a relatively common injury. They often involve the hand and may have serious sequelae because of the structures involved, the bacteriologic spectrum, or poor patient compliance with the treatment regimen. A careful history and physical examination are important, and treatment involves good local wound care, appropriate antibiotic coverage (including both a penicillin and a penicillinase-resistant penicillin), immobilization and elevation of the injured area, and close follow-up, as well as early rehabilitation.  相似文献   
109.
Age is a potential source of variation that contributes to differences between, but not within, twin pairs. In most genetic analyses of twin data, linear and other functions of age are usually removed prior to model fitting. This correction is typically applied only within twin groups of the same sex and zygosity, and no heterogeneity test of age regressions is performed. Here we include age as a variable in the model-fitting procedure and allow for tests of heterogeneity of age regressions across sex and zygosity groups. The LISREL formulation of the approach is illustrated with data collected from Australian twins on subjective impressions of drunkenness following alcohol consumption. The results indicate significant negative covariation of impressions of drunkenness with age. The data support a simple model of additive genetic and unique environmental variation. No evidence was found for sex differences in genetic or environmental components of variation.The theoretical work and data analysis described in this paper were made possible by NATO Grant 86/0823 and grants from the Belgian National Research Fund, the State University of Gent, and the Catholic University of Leuven. We are also grateful to Drs. R. Vlietinck and R. Derom for excellent organization of the successful workshop. Data collection was made possible by a grant from the Australian Associated Brewers to N.G.M. and Drs. J. G. Oakeshott, J. B. Gibson, and G. A. Starmer and by grants from the Australian National Health and Medical Research Council. The authors were supported by NIH Grants MH-40828 and AA-06781.  相似文献   
110.
Objectives
To explore medical students' use of computer tutorials embedded in a busy clinical setting; to demonstrate that such tutorials can increase knowledge gain over and above that attributable to the clinical rotation itself.
Methods
Six tutorials were installed on a computer placed in a central area in an emergency department. Each tutorial was made up of between 33 and 85 screens of information that include text, graphics, animations, and questions. They were designed to be brief (10 minutes), focused, interactive, and immediately relevant. The authors evaluated the intervention using quantitative research methods, including usage tracking, surveys of faculty and students, and a randomized pretest-posttest study.
Results
Over 46 weeks, 95 medical students used the tutorials 544 times, for an overall average of 1.7 times a day. The median time spent on completed tutorials was 11 minutes (average [SD], 14 [±12] minutes). Seventy-four students completed the randomized study. They completed 65% of the assigned tutorials, resulting in improved examination scores compared with the control (effect size, 0.39; 95% confidence interval = 0.15 to 0.62). Students were positively disposed to the tutorials, ranking them as "valuable." Fifty-four percent preferred the tutorials to small group teaching sessions with a preceptor. The faculty was also positive about the tutorials, although they did not appear to integrate the tutorials directly into their teaching.
Conclusions
Medical students on rotation in a busy clinical setting can and will use appropriately presented computer tutorials. The tutorials are effective in raising examination scores.  相似文献   
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