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OBJECTIVE: To determine the effectiveness of a 10-day subcutaneous erythropoietin (rHuEpo) course of 300 units per kg per dose plus oral iron compared to oral iron alone in anemic infants during their convalescent phase of illness. STUDY DESIGN: Prospective, randomized trial performed at a 40-bed, teaching, referral, level III, neonatal intensive care unit. Infants with a gestational age at birth of less than 32 weeks, hematocrit of less than or equal to 28% with a corrected reticulocyte count of less than or equal to 5%, postconceptual age of less than 48 weeks or 5 months chronological age, and a diagnosis of anemia of prematurity were considered for inclusion. Major outcome parameters included hematocrit, corrected reticulocyte count and red cell transfusion requirements. RESULTS: A total of 60 infants were enrolled (n=30 per group). Infants randomized to rHuEpo had a significantly higher post-treatment hematocrit and corrected reticulocyte count than infants in the iron only group (p<0.001). There was a trend towards fewer red cell requirements in the rHuEpo group. CONCLUSIONS: The rHuEpo regimen studied here was associated with an acute improvement in hematocrit and corrected reticulocyte counts. This study did not demonstrate a statistically significant decrease in transfusion therapy, in part related to increased subsequent use of rHuEpo in the control group. Taken together, these data demonstrate that this regimen can effectively treat anemia in convalescent premature infants.  相似文献   
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Castleman disease in an 11-year-old girl appeared as a neck mass that grew despite antibiotic treatment. MR showed a well-defined solid mass, isointense with muscle on short-repetition-time/short-echo-time images, with a stellate area of central hypointensity on long-repetition-time/long-echo-time images, that did not enhance with gadolinium.  相似文献   
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Melatonin reduces nitric oxide synthase activity in rat hypothalamus   总被引:2,自引:0,他引:2  
Abstract: In this report, rat hypothalamic nitric oxide synthase (NOS) activity is shown to be partially inhibited by physiological concentrations of the pineal hormone melatonin. In vitro studies demonstrate that 1 nM melatonin, which approximates the physiological concentration of the hormone at night, significantly inhibited NOS activity. In vivo studies show that administering melatonin or collecting the hypothalamus from animals at night, when endogenous melatonin levels are elevated, results in a significant decrease of NOS activity. Results also show that calmodulin may be involved in this process since its presence in the incubation medium prevents the inhibitory effect of melatonin on NOS activity.  相似文献   
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PURPOSE: To assess the consistency of ratings assigned by health sciences faculty members relative to community members during an innovative admissions protocol called the Multiple Mini-Interview (MMI). METHOD: A nine-station MMI was created and 54 candidates to an undergraduate MD program participated in the exercise in Spring 2003. Three stations were staffed with a pair of faculty members, three with a pair of community members, and three with one member of each group. Raters completed a four-item evaluation form. All participants completed post-MMI questionnaires. Generalizability Theory was used to examine the consistency of the ratings provided within each of these three subgroups. RESULTS: The overall test reliability was found to be .78 and a Decision Study suggested that admissions committees should distribute their resources by increasing the number of interviews to which candidates are exposed rather than increasing the number of interviewers within each interview. Divergence of ratings was greater within the pairing of community member to faculty member and least for pairings of community members. Participants responded positively to the MMI. CONCLUSION: The MMI provides a reliable protocol for assessing the personal qualities of candidates by accounting for context specificity with a multiple sampling approach. Increasing the heterogeneity of interviewers may increase the heterogeneity of the accepted group of candidates. Further work will determine the extent to which different groups of raters provide equally valid (albeit different) judgments.  相似文献   
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Axillary artery-to-coronary artery bypass using reversed saphenous vein provides a simple method of applying the minimally invasive coronary bypass grafting procedure when the internal thoracic artery is not an adequate conduit. Although this may allow extended use of the minimally invasive coronary bypass procedure, the long-term patency of this technique is unknown.  相似文献   
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Summary. Bone mineralisation during and after limb lengthening procedures on the femur or tibia using unilateral fixators has been monitored quantitatively using dual energy X-ray absorptiometry (DEXA). We measured the bone mineral density (BMD) prospectively in the newly formed callus, in the bone adjacent to the callus and in the proximal femur. In twenty-one patients we showed a typical course with a peak value at 4 – 6 weeks after beginning distraction and a minimum value at maximum distraction. In the consolidation period the BMD in the distraction gap increased until the fixator was removed. The BMD in the regenerated bone increased faster in the regions of interest (ROI) opposite the fixator compared to those near it. Dynamisation caused more homogeneous regeneration equalising V BMD in the different ROIs. The BMD in the proximal femur of the leg which was operated on decreased to 67% and in the opposite leg to 87% of the preoperative value. DEXA provides a precise and quantitative assessment of callus and bone mineralisation during limb lengthening and helps in understanding what is happening during these procedures.
Résumé. Le processus de la minéralisation peut précisément être étudié d’une manière quantitative pendant et après la distraction du cal au moyen de l’absorptiométrie en énergie-binaire (DEXA) en créant une petite radioexposition. Des patients (n = 21) avec une distraction du cal, auxquels nous avons mesuré prospectivement la densité minérale de l’os (bone mineral density = BMD) dans et autour du cal nouvellement formé, étaient traités avec des fixateurs externes unilatéraux. La minéralisation a montré une courbe typique avec une première pointe de valeur [0,365 +/– 0,196 g/cm 2 (30,9% de la première valeur)] à 4 – 6 semaines après le début de la distraction. Une valeur minimale apparut à la distraction maximale. Dans la période de consolidation la BMD est montèe jusqu’au moment de l’enlèvement du fixateur à 1,020 +/– 0,234 g/cm2 (87%). La minéralisation du cal, mésurée grace à la technique des ?regions of interest (ROIs)?, augmenté plus vite aux ROIs éloignées qu’aux ROIs très proches du fixateur. De la dynamisation du fixateur résulte une vitesse de minéralisation plus homogène. Nous considérons la DEXA comme une méthode précise pour étudier les processus de la minéralisation et du développement du cal pendant la distraction avec un fixateur unilatéral. En tenant compte des limites de la technique, la DEXA – qui nous livre des valeurs quantitatives – nous aide à comprendre ce qui se passe pendant la distraction.


Accepted: 11 July 1996  相似文献   
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