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排序方式: 共有903条查询结果,搜索用时 31 毫秒
1.
Objective: To determine whether packed red blood cell (PRBC) transfusion affects post-prandial superior mesenteric artery blood flow velocities (SMA BFVs) in very-low birth weight (VLBW) neonates and if so, at what time point after transfusion restoration of previous SMA BFV patterns occurs.

Design/Methods: VLBW pre-term neonates, older than 14 days and tolerating bolus enteral feedings administered every 3?h were enrolled in this prospective observational study. Pulsed Doppler ultrasound was used to measure pre- and post-prandial (at 45?min) time-averaged mean, peak and end diastolic velocities (TAMV, PSV, EDV) immediately before and after 15?ml/kg of PRBC transfusion was given over 3?h; patent ductus arteriosus (PDA) status was also evaluated. Subsequent pre- and post-prandial SMA BFVs were recorded 24 and 48?h after the transfusion.

Results: Pre- and post-prandial measurements were obtained for 21 out of 25 enrolled infants. Post-prandial SMA BFVs were attenuated during the feedings immediately after transfusion; at 24 and 48?h after transfusion, changes in post-prandial SMA BFVs were similar to those measured prior to transfusion; the presence of the PDA did not affect results.

Conclusions: PRBC transfusion blunted SMA BFV responses to feedings immediately after the transfusion with normalization observed 24?h post-transfusion.  相似文献   
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Healthcare information systems (HISs) are often implemented to enhance the quality of care and the degree to which it is patient-centered, as well as to improve the efficiency and safety of services. However, the outcomes of HIS implementations have not met expectations. We set out to organize the knowledge gained in qualitative studies performed in association with HIS implementations and to use this knowledge to outline an updated structure for implementation planning. A multi-disciplinary team performed the analyses in order to cover as many aspects of the primary studies as possible. We found that merely implementing an HIS will not automatically increase organizational efficiency. Strategic, tactical, and operational actions have to be taken into consideration, including management involvement, integration in healthcare workflow, establishing compatibility between software and hardware and, most importantly, user involvement, education and training. The results should be interpreted as a high-order scheme, and not a predictive theory.  相似文献   
4.
Dactylolysis spontanea is an idiopathic condition affecting the fifth toe, and sometimes other toes, that is frequently bilateral, with lesions in different stages. Between 1977 and 1999, a total 6000 radiographic studies of the feet were reviewed in a mainly African American population in Chicago, Illinois. After an initial screening based on the Cole criteria, 581 patients were selected and re-examined, and amplification techniques were performed. After reviewing the complementary exams, 102 patients were diagnosed with dactylolysis spontanea or ainhum. Soft-tissue constriction was the most frequently presented radiological sign on the initial screening. Kurtosis at the digit plantar fold and marked rotation of the fifth toe were normal findings in asymptomatic patients. Demographics, comorbidities, and radiological findings were analyzed in the selected population. Associated diseases occurring in these patients appeared to have no specific etiologic correlation with ainhum. African Americans and the dark-skinned population are affected exclusively by this condition, presumably due to the fibrogenic tendency of these individuals. Early diagnosis and accurate staging of ainhum are facilitated by radiological examination of the feet. The findings suggest that this condition is underdiagnosed and overlooked because its low prevalence and variable clinical presentations that might mimic more common etiologies, including localized trauma.  相似文献   
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Nociceptin/orphanin FQ (N/OFQ), the endogenous ligand of the opioid receptor-like receptor or nociceptin receptor (NOP), has been shown to induce feeding, locomotion, anti-stress and anxiolytic effects in rodents after central nervous system injection. In this study, the effect of intracerebroventricular (icv) injection of N/OFQ on feeding and locomotion behavior was evaluated in male broiler-type chickens. The icv injection of N/OFQ caused a moderate but significant increase in feed intake similar to the classical opioid peptides in rats. It also increased feed pecking frequency and feeding time 1 h after injection. Stepping, wing flapping and preening were not affected by N/OFQ. These results suggest that N/OFQ can act within the central nervous system of chickens to increase feed intake.  相似文献   
6.
Disseminated Pneumocystis carinii in thymic alymphoplasia   总被引:2,自引:0,他引:2  
  相似文献   
7.
AIMS--(1) To assess the diagnostic relevance of peripheral blood immunocytochemistry in hairy cell leukaemia (HCL); (2) to compare the immunostaining of bone marrow biopsy specimens with bone marrow and peripheral blood cytospins; (3) to evaluate the sensitivity of the different markers used; (4) to identify the ultrastructural localisation of DBA.44 in HCL variant. METHODS--Immunoenzymatic staining procedures, immunoperoxidase and immunoalkaline phosphatase, were used with a panel of monoclonal antibodies directed to HCL associated antigens. Ultrastructural immunostaining was performed using colloidal gold conjugated antibodies. RESULTS--HCL showed strong cytoplasmic reactivity for CD22, CD25, CD103, DBA.44, kappa, or lambda light chains. Peripheral blood diagnostic hairy cells were found in all the cases with absolute counts ranging from 0.11 x 10(9)/l up to 6.4 x 10(9)/l and values increasing with the size of the spleen. A median of 36.5% of leukaemic cells was found in bone marrow aspirates and 70% in bone marrow trephine specimens. The monoclonal antibodies CD22 and DBA.44 showed the highest and the lowest percentage of positive hairy cells, respectively; this difference was statistically significant (p = 0.0025). Ultrastructural immunolabelling with DBA.44 showed a cytoplasmic membrane localisation of the antigen in one case of HCL variant. CONCLUSIONS--(1) Immunocytochemistry is a useful technique which enhances the accuracy of diagnosis in HCL; (2) peripheral blood immunocytochemistry is recommended because it highlights hairy cells in all cases; (3) CD22 appears to be the most sensitive of the markers tested; (4) ultrastructural analysis is a useful tool in selected cases of HCL variant.  相似文献   
8.
Mahogunin Ring Finger 1 (Mgrn1) encodes a RING-containing protein with ubiquitin ligase activity that has been implicated in pigment-type switching. In addition to having dark fur, mice lacking MGRN1 develop adult-onset spongy degeneration of the central nervous system and have reduced embryonic viability. Observation of complete situs inversus in a small proportion of adult Mgrn1 mutant mice suggested that embryonic lethality resulted from congenital heart defects due to defective establishment and/or maintenance of the left-right (LR) axis. Here we report that Mgrn1 is expressed in a pattern consistent with a role in LR patterning during early development and that many Mgrn1 mutant embryos show abnormal expression of asymmetrically expressed genes involved in LR patterning. A range of complex heart defects was observed in 20-25% of mid-to-late gestation Mgrn1 mutant embryos and another 20% were dead. This finding was consistent with 46-60% mortality of mutants by weaning age. Our results indicate that Mgrn1 acts early in the LR signaling cascade and is likely to provide new insight into this developmental process as Nodal expression was uncoupled from expression of other Nodal-responsive genes in Mgrn1 mutant embryos. Our work identifies a novel role for MGRN1 in embryonic patterning and suggests that the ubiquitination of MGRN1 target genes is essential for the proper establishment and/or maintenance of the LR axis.  相似文献   
9.
Objectifying donor lung quality is difficult and currently there is no consensus. Several donor scoring systems have been proposed in recent years. They all lack large-scale external validation and widespread acceptance. A retrospective evaluation of 2201 donor lungs offered to the lung transplant program at the Medical University of Vienna between January 2010 and June 2018 was performed. Five different lung donor scores were calculated for each offer (Oto, ET, MALT, UMN-DLQI, and ODSS). Prediction of organ utilization, 1-year graft survival, and long-term outcome were analyzed for each score. 1049 organs were rejected at the initial offer (group I), 209 lungs declined after procurement (group II), and 841 lungs accepted and transplanted (group III). The Oto score was superior in predicting acceptance of the initial offer (AUC: 0.795; CI: 0.776–0.815) and actual donor utilization (AUC: 0.660; CI: 0.618–0.701). Prediction of 1-year graft survival was best using the MALT score, Oto score, and UMN-DLQI. Stratification of early outcome by MALT was significant for length of mechanical ventilation (LMV), PGD3 rates, ICU stay and hospital stay, and in-hospital-mortality, respectively. To the best of our knowledge, this study is the largest validation analysis comparing currently available donor scores. The Oto score was superior in predicting organ utilization, and MALT score and UMN-DLQI for predicting outcome after lung transplantation.  相似文献   
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