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41.

Introduction

Extremely high glucose concentrations have been shown to interfere with creatinine assays especially with Jaffe method in peritoneal dialysate. Because diabetes is the fastest growing chronic disease in the world, laboratories study with varying glucose concentrations. We investigated whether different levels of glucose spiked in serum interfere with 21 routine chemistry and thyroid assays at glucose concentrations between 17-51 mmol/L.

Materials and methods

Baseline (group I) serum pool with glucose concentration of 5.55 (5.44-5.61) mmol/L was prepared from patient sera. Spiking with 20% dextrose solution, sample groups were obtained with glucose concentrations: 17.09, 34.52, and 50.95 mmol/L (group II, III, IV, respectively). Total of 21 biochemistry analytes and thyroid tests were studied on Abbott c8000 and i2000sr with commercial reagents. Bias from baseline value was checked statistically and clinically.

Results

Creatinine increased significantly by 8.74%, 31.66%, 55.31% at groups II, III, IV, respectively with P values of < 0.001. At the median glucose concentration of 50.95 mmol/L, calcium, albumin, chloride and FT4 biased significantly clinically (-0.85%, 1.63%, 0.65%, 7.4% with P values 0.138, 0.214, 0.004, < 0.001, respectively). Remaining assays were free of interference.

Conclusion

Among the numerous biochemical parameters studied, only a few parameters are affected by dramatically increased glucose concentration. The creatinine measurements obtained in human sera with the Jaffe alkaline method at high glucose concentrations should be interpreted with caution. Other tests that were affected with extremely high glucose concentrations were calcium, albumin, chloride and FT4, hence results should be taken into consideration in patients with poor diabetic control.Key words: assay interference, glucose interference, preanalytical phase, creatinine, Jaffe kinetic assay, thyroid function tests  相似文献   
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PURPOSE: This paper examines individual, family, and neighborhood level predictors of resilience in adolescence and young adulthood and describes changes in resilience over time from adolescence to young adulthood in abused and neglected children grown up. METHOD: We use documented cases of childhood physical and sexual abuse and neglect (n=676) from a Midwestern county area during the years 1967-1971 and information from official records, census data, psychiatric assessments, and self-reports obtained through 1995. Analyses involve logistic regressions, replicated with Mplus to test for possible contextual effects. RESULTS: Almost half (48%) of the abused and neglected children in adolescence and nearly one-third in young adulthood were resilient. Over half of those who were resilient in adolescence remained resilient in young adulthood, whereas 11% of the non-resilient adolescents were resilient in young adulthood. Females were more likely to be resilient during both time periods. Being white, non-Hispanic decreased and growing up in a stable living situation increased the likelihood of resilience in adolescence, but not in young adulthood. Stressful life events and a supportive partner promoted resilience in young adulthood. Neighborhood advantage did not exert a direct effect on resilience, but moderated the relationship between household stability and resilience in adolescence and between cognitive ability and resilience in young adulthood. CONCLUSIONS: Ecological factors appear to promote or interfere with the emergence and stability of resilience following childhood maltreatment.  相似文献   
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IPv4, the workhorse protocol of the currently popular TCP/ IP protocol suite, is fast becoming obsolete. The exponential growth of the Internet is the main reason that has required the creation of the next generation of Internet Protocol-IPv6. IPv6 is much more flexible and promises to take care of the address space and security issues in the foreseeable future. Part 1 of the paper lays the foundation of the various issues involved in designing the Internet Protocol and motivates the need for an upgraded version of this protocol.  相似文献   
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In many Western science systems, funding structures increasingly stimulate academic research to contribute to practical applications, but at the same time the rise of bibliometric performance assessments have strengthened the pressure on academics to conduct excellent basic research that can be published in scholarly literature. We analyze the interplay between these two developments in a set of three case studies of fields of chemistry in the Netherlands. First, we describe how the conditions under which academic chemists work have changed since 1975. Second, we investigate whether practical applications have become a source of credibility for individual researchers. Indeed, this turns out to be the case in catalysis, where connecting with industrial applications helps in many steps of the credibility cycle. Practical applications yield much less credibility in environmental chemistry, where application-oriented research agendas help to acquire funding, but not to publish prestigious papers or to earn peer recognition. In biochemistry practical applications hardly help in gaining credibility, as this field is still strongly oriented at fundamental questions. The differences between the fields can be explained by the presence or absence of powerful upstream end-users, who can afford to invest in academic research with promising long term benefits.  相似文献   
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