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991.
Italian Network for Quality Assurance of Tumor Biomarkers 《The International journal of biological markers》2005,20(3):189-194
The clinical interest in HER-2/neu is related to trastuzumab, a drug used to treat patients with invasive breast carcinoma overexpressing the HER-2/neu protein. It is very important to correctly identify those patients who may benefit from trastuzumab by accurate assessment of the HER-2/neu status. Of the various methods available, the Dako Herceptest for immunohistochemical assay is considered the most reliable to reach this goal. The aim of this study was to investigate within a group of Italian laboratories the reproducibility of the results of HER-2/neu assessment by means of the Dako scoring system on slides stained with the Herceptest kit. This study was also conceived as the continuation of one of our previous studies, which was similar in its aims but different in the classification criteria adopted. Our results show that, whereas the intra-observer reproducibility was generally satisfactory, the interobserver reproducibility was not. Moreover, our findings confirm that the two extreme classes (0 and 3+) are more easy to identify than the other two and that the Herceptest does not allow to discriminate optimally between scoring classes 2+ and 3+. These findings are relevant in clinical practice where the treatment choice is based on categories defined by this assay, suggesting the need of adopting educational programs and/or new reference materials to improve the assay performance. 相似文献
992.
Italian Network for Quality Assessment of Tumor Biomarkers Group 《The International journal of biological markers》2005,20(4):264-268
Chromogranin A (CgA) is a secretory protein produced by many neuroendocrine cells. Circulating levels of CgA have been found to be elevated in a variety of neuroendocrine tumors and may facilitate the diagnosis and management of patients with functioning as well as non-functioning forms. However, up to now the analytical methods used for assaying intact CgA and CgA-derived peptides in the circulation of patients have not been monitored in Italy by an external quality control program. Within the framework of a Ministry of Health project an external quality control program was developed to investigate the state of the art of CgA determination in Italy and to monitor the performance of laboratories carrying out this assay. This paper deals primarily with the former of these aspects. Every laboratory received the study protocol together with a questionnaire to be returned before receipt of the samples to be assayed. Serum and plasma samples obtained from a pool of routine specimens were prepared at three different concentrations of CgA, aliquoted, frozen at -80 degrees C and mailed in dry ice to the participating laboratories. Of the 43 laboratories, 21 used IRMA, 21 used ELISA and one used RIA. There was a wide range in the time of kit utilization and the number of samples assayed per year, which indicated that the participating group was heterogeneous with regard to their experience in the determination of CgA. Most laboratories routinely used serum and plasma for IRMA and ELISA, respectively, and different data fitting approaches were employed. Further analyses will investigate the possible influence of these preanalytical factors on laboratory performance. 相似文献
993.
BACKGROUND/AIM: Central precocious puberty (CPP) is more common in females than in males. During the last few decades a new group of patients with CPP has been seen frequently in Northern Europe, namely children adopted from developing countries. GnRH analogue preparations, administered either as intranasal spray or as depot preparations, are the drugs of choice for inhibiting the release of gonadotropins. The aim of this study was to compare the effect of buserelin given by intranasal spray with that of the same compound given as a subcutaneous depot preparation. METHODS: The study group comprised 46 pubertal girls below the age of 9.5 years, adopted from a developing country. During the first 2 years, the treatment used was buserelin acetate 300 microg 6 times daily as a nasal spray. During the third year the treatment was changed to Suprefact Depot, 6.3 mg, given as a subcutaneous implant every 8 weeks. Half of the girls were randomized to growth hormone treatment in addition to the pubertal inhibition. RESULTS: GnRH provocation tests after 6 weeks, 1 year and 2 years of treatment with intranasal GnRH analogue showed suppression of gonadotropin secretion except in 1 case of noncompliance. During the third year, when the long-acting depot preparation was used, suppression was more pronounced. The peak LH response, especially, was considerably lower than during treatment with the nasal spray preparation. In all cases the clinical inhibition of puberty was adequate both during the first two years and during the third year. CONCLUSION: Even though the clinical suppression of puberty was adequate with both modes of administration, the effect of the depot preparation, in this study Suprefact Depot, was more pronounced in terms of gonadotropin suppression and less dependent on patient compliance. 相似文献
994.
Landys-Ciannelli MM Ramenofsky M Piersma T Jukema J Wingfield JC;Castricum Ringing Group 《Physiological and biochemical zoology : PBZ》2002,75(1):101-110
The specific roles of corticosterone in promotion of avian migration remain unclear even though this glucocorticosteroid is elevated in many migrating bird species. In general, glucocorticosteroids promote metabolic homeostasis and may elicit effects on feeding and locomotion. Because the migratory stages of refueling and flight are characterized by distinct behaviors and physiology, the determination of corticosterone levels during each stage should help identify potential processes in which corticosterone is involved. We measured baseline levels of corticosterone in bar-tailed godwits (Limosa lapponica) during two distinct stages of migration: (1) immediately after arrival at a false stopover site just short of the Wadden Sea and (2) throughout the subsequent 4-wk refueling period on the Wadden Sea. Plasma corticosterone was higher in arriving than in refueling birds. In addition, corticosterone increased with size-corrected body mass during the refueling phase, suggesting that corticosterone rises as birds prepare to reinitiate flight. Therefore, elevated corticosterone appears associated with migratory flight and may participate in processes characterizing this stage. We also performed a capture stress protocol in all birds and found that corticosterone increased in both arriving and refueling godwits. Therefore, the normal course of migration may be typified by corticosterone concentrations that are lower than those associated with stressful and life-threatening episodes. 相似文献
995.
bZIP transcription factors in Arabidopsis 总被引:28,自引:0,他引:28
996.
Johanneson B Lima G von Salomé J Alarcón-Segovia D Alarcón-Riquelme ME;Collaborative Group on the Genetics of SLE The BIOMED II Collaboration on the Genetics of SLE Sjögrens syndrome 《American journal of human genetics》2002,71(5):1060-1071
A set of 87 multicase families with systemic lupus erythemathosus (SLE) from European (Iceland, Sweden, England, Norway, Italy, and Greece) and recently admixed (Mexico, Colombia, and the United States) populations were genotyped and analyzed for 62 microsatellite markers on chromosome 1. By parametric two-point linkage analysis, six regions (1p36, 1p21, 1q23, 1q25, 1q31, and 1q43) were identified that have LOD scores of Z>or=1.50, with different contributions, depending on the population of origin of the families (European or admixed American). All of the regions have been described previously and have therefore been confirmed in this analysis. The locus at 1q31 showed a significant three-point LOD score of Z=3.79 and was contributed by families from all populations, with several markers and under the same parametric model. Analysis of a known mutation in the CD45 gene did not support the role that this mutation plays in disease. We conclude that the locus at 1q31 contains a major susceptibility gene, important to SLE in general populations. 相似文献
997.
Diagnostic and prognostic value of flow cytometric immunophenotyping in malignant hematological diseases 总被引:11,自引:0,他引:11
Chianese R Brando B Gratama JW;European Working Group on Clinical Cell Analysis 《Journal of biological regulators and homeostatic agents》2002,16(4):259-269
Flow cytometry is a diagnostic cell analysis technique with ever increasing applications in modern hematological practice. To date immunophenotyping of clonal hematological diseases represents one of the primary clinical applications of flow cytometry. Immunophenotyping of abnormal cells is now considered a fundamental tool to establish the cell lineage assignment and to obtain a more precise identification of the various cell subtypes. A number of observations have emerged showing strong association between specific immunophenotypes and genetic recurrent abnormalities underlying the malignant transformation, with prognostic value. 相似文献
998.
999.
Sharleen L. O’Reilly James A. Dunbar Vincent Versace Edward Janus James D. Best Rob Carter Jeremy J. N. Oats Timothy Skinner Michael Ackland Paddy A. Phillips Peter R. Ebeling John Reynolds Sophy T. F. Shih Virginia Hagger Michael Coates Carol Wildey MAGDA Study Group 《PLoS medicine》2016,13(7)
BackgroundGestational diabetes mellitus (GDM) is an increasingly prevalent risk factor for type 2 diabetes. We evaluated the effectiveness of a group-based lifestyle modification program in mothers with prior GDM within their first postnatal year.ConclusionsAlthough a 1-kg weight difference has the potential to be significant for reducing diabetes risk, the level of engagement during the first postnatal year was low. Further research is needed to improve engagement, including participant involvement in study design; it is potentially more effective to implement annual diabetes screening until women develop prediabetes before offering an intervention.
Trial Registration
Australian New Zealand Clinical Trials Registry ACTRN12610000338066 相似文献1000.
Paula Elouafkaoui Linda Young Rumana Newlands Eilidh M. Duncan Andrew Elders Jan E. Clarkson Craig R. Ramsay Translation Research in a Dental Setting Research Methodology Group 《PLoS medicine》2016,13(8)
BackgroundDentists prescribe approximately 10% of antibiotics dispensed in UK community pharmacies. Despite clear clinical guidance, dentists often prescribe antibiotics inappropriately. This cluster-randomised controlled trial used routinely collected National Health Service (NHS) dental prescribing and treatment claim data to compare the impact of individualised audit and feedback (A&F) interventions on dentists’ antibiotic prescribing rates.ConclusionsA&F derived from routinely collected datasets led to a significant reduction in the antibiotic prescribing rate of dentists.