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111.
Fessas  P; Anagnou  NP; Loukopoulos  D 《Blood》1980,55(4):564-569
L-alpha-Glycerol-3-phosphate dehydrogenase (EC 1.1.1.8) has been reported to be absent in the erythrocytes of normal adults, but can be found in those of cord blood and of thalassemia major. The aid of this study was to investigate whether there is any relation between GDH and gamma-chain synthesis. Erythrocyte GDH activity was determined on 118 different blood samples. It was undetectable in normal adult erythrocytes and definitely high in cord blood cells (23.6 UI/10(11) RBC). Considerable GDH activity was also noted in patients with thalassemia major (11.0 IU10(11) RBC) as well as in cases with pronounced reticulocytosis (11.4 IU/10(11) RBC). Red cells from beta- thalassemia heterozygotes exhibited moderate but distinct GDH activity (5.2 IU/10(11) RBC). After fractionation into young and old erythrocyte populations, clearly higher GDH activity was found in the younger cells; however, there was no significant correlation with the reticulocyte count. Presence of reticulocytes alone appears insufficient to explain the values obtained in cord blood and the thalassemias, especially heterozygous. Furthermore, no direct correlation between GDH and fetal hemoglobin (HbF) was obtained in cord and thalassemic erythrocytes.  相似文献   
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This study aimed to investigate the influence of antiretroviral therapy on methylation markers, in a group of HIV infected, heavily treated patients. Immune and molecular methods were used to investigate potential changes in methylation profile in DNA isolated from peripheral blood mononuclear cells collected from antiretroviral-experienced HIV infected patients and healthy controls. The percentage of 5-methylcytosine was inversely correlated with proviral DNA and active replication while DNMT1 (p = 0.01) and DNMT3A (p = 0.004) independently correlated with active viral replication. DNMT3A expression increased with total treatment duration (p = 0.03), number of antiretroviral drugs ever used (p = 0.003), and cumulative exposure to protease inhibitors (p = 0.02) even in currently HIV undetectable patients.  相似文献   
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This article describes childbirth simulation design and implementation within the nurse‐midwifery education program at the University of California, San Francisco. Nurse‐midwife and obstetrician faculty coordinators were supported by faculty from multiple professions and specialties in curriculum review and simulation development and implementation. The primary goal of the resulting technology‐enhanced simulations of normal physiologic birth and obstetric emergencies was to assist learners’ development of interprofessional competencies related to communication, teamwork, and patient‐centered care. Trainees included nurse‐midwifery students; residents in obstetrics, pediatrics, and family medicine; medical students; and advanced practice nursing students in pediatrics. The diversity of participant types and learning levels provided benefits and presented challenges to effective scenario‐based simulation design among numerous other theoretical and logistical considerations. This project revealed practical solutions informed by emerging health sciences and education research literature, faculty experience, and formal course evaluations by learners. Best practices in simulation development and implementation were incorporated, including curriculum revision grounded in needs assessment, case‐ and event‐based clinical scenarios, optimization of fidelity, and ample time for participant debriefing. Adequate preparation and attention to detail increased the immersive experience and benefits of simulation. Suggestions for fidelity enhancement are provided with examples of simulation scenarios, a timeline for preparations, and discussion topics to facilitate meaningful learning by maternity and newborn care providers and trainees in clinical and academic settings. Pre‐ and postsimulation measurements of knowledge, skills, and attitudes are ongoing and not reported. This article is part of a special series of articles that address midwifery innovations in clinical practice, education, interprofessional collaboration, health policy, and global health.  相似文献   
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Purpose: To evaluate the factors affecting the sensitivity and specificity of the stereometric optic nerve head (ONH) parameters of the Heidelberg Retina Tomograph (HRT) to glaucomatous progression in stereoscopic ONH photographs. Methods: The factors affecting the sensitivity and specificity of the vertical cup : disc ratio, the cup : disc area ratio, the cup volume, the rim area and a linear discriminant function to progression were analysed. These parameters were the best indicators of progression in a retrospective study of 476 eyes. The reference standard for progression was the masked evaluation of stereoscopic ONH photographs. Results: The factors having the most significant effect on the sensitivity and specificity of the stereometric ONH parameters were the reference height difference and the mean topography standard deviation (TSD), indicating image quality. Also, the change in the TSD and age showed consistent, but variably significant, influence on all parameters tested. The sensitivity and specificity improved when there was little change in the reference height, the image quality was good and stable, and the patients were younger. The sensitivity and specificity of the vertical cup : disc ratio was improved by a large disc area and high baseline cup : disc area ratio. The rim area showed a better sensitivity and specificity for progression with a small disc area and low baseline cup : disc area ratio. Conclusion: The factors affecting the sensitivity and specificity of the stereometric ONH parameters to glaucomatous progression in disc photographs are essentially the same as those affecting the measurement variability of the HRT.  相似文献   
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