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991.
The purpose of this study was to determine an association between packed red blood cell (PRBC) transfusions for anemia and necrotizing enterocolitis (NEC) in a subset of stable, growing, premature neonates. As part of a survey of current clinical practices over a 17-month period from June 1999 to October 2000, a chart review was performed to determine the relationship between elective PRBC transfusions and the occurrence of NEC. Demographic data were tabulated and compared between the NEC patients with a prior history of immediate blood transfusion (within 48 hours of onset of symptoms) and those NEC patients without a prior history of immediate blood transfusion. A total of 908 (inborn) neonatal admissions had received 751 PRBC transfusions during the study period; of these, 17 patients (1.8%) had developed radiographic, clinical, or surgical signs of NEC. Six cases of NEC (35%; six of 17 patients) were associated with PRBC transfusions (0.8%; six of 751 transfusions). The transfusion-associated NEC group developed presenting signs within 22 +/- 5 hours (median, 19; range, 12 to 38) of a PRBC transfusion at a mean age of 32 +/- 7 days. In contrast, the non-transfusion-associated NEC group (n = 11) had onset of NEC at a mean age of 12 +/- 7 days ( P < 0.05) after 185 +/- 91 hours (median, 180; range, 96 to 312; P < 0.02] of a transfusion. Prior to the onset of NEC, all of the neonates in the transfusion-associated NEC group were stable, growing, not ventilated, receiving full enteral feedings, and had no other active medical problems except anemia (hematocrit, 24 +/- 3%). In contrast, the nontransfusion NEC group was more often ventilated, was receiving < 50% of fluids by mouth, had lower Apgar scores, and was transfused for an average hematocrit of 37 +/- 7% ( P < 0.05). There was no significant difference in the type, storage, volume, or preservative used between the blood products in the two groups. We identified an unanticipated relationship between late-onset NEC in stable, growing, premature neonates who were transfused electively for anemia of prematurity.  相似文献   
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An 8-year-old girl with linear scleroderma “en coup de sabre” is reported who, at preschool age, presented with intractable simple partial seizures more than 1 year before skin lesions were first noticed. MRI revealed hippocampal atrophy, controlaterally to the seizures and ipsilaterally to the skin lesions. In the following months, a mental and motor regression was noticed. Cerebral CT scan showed multiple foci of calcifications in the affected hemisphere. In previously reported patients the skin lesions preceded the neurological signs. To the best of our knowledge, hippocampal atrophy was not earlier reported as presenting symptom of linear scleroderma. Linear scleroderma should be included in the differential diagnosis in patients with unilateral hippocampal atrophy even when the typical skin lesions are not present.  相似文献   
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 Variations in dietary phosphate (Pi) intake in rats lead to alterations of renal Pi reabsorption. These effects are associated with corresponding changes in the abundance of the type II Na/Pi-cotransporter protein in proximal tubular brush-border membranes. In the present study we investigated the regulation of the type II Na/Pi-cotransporter in response to high- and low-Pi medium in opossum kidney (OK) cells, an epithelial cell-line of proximal tubular origin. We show that ”acute” (4 h) and ”chronic” (24 h) exposures of OK cells to high- or low-Pi medium lead to decreases or increases, respectively, in Na/Pi-cotransport activity which are paralleled by alterations in the total cellular amount of the corresponding type II Na/Pi-cotransporter protein (NaPi-4), but not by changes in the amount of the NaPi-4 mRNA. Also in OK cells transfected with the corresponding rat renal type II Na/Pi-cotransporter (NaPi-2) alterations in the Pi concentration in the medium lead to changes in the amount of NaPi-2 protein but not in the amount of NaPi-2 mRNA. Furthermore we show that lysosomal inhibitors prevent the degradation of the transporter, but do not interfere with its inhibition, in response to ”acute” exposure of OK cells to high-Pi medium. Inhibition of lysosomal degradation also leads, in control conditions, to an accumulation of the transporter detectable on Western blot. It is concluded that the lysosomal proteolytic pathway is not only involved in the Pi-induced downregulation of the type II Na/Pi-cotransporter but also in its basic turnover. Received: 7 October 1997 / Received after revision and accepted: 5 December 1997  相似文献   
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Background  

Accurate histopathological evaluation of resected lymph nodes (LN) is essential for the reliable staging of colorectal carcinomas (CRC). With conventional sectioning and staining techniques usually only parts of the LN are examined which might lead to incorrect tumor staging. A molecular method called OSNA (One Step Nucleic Acid Amplification) may be suitable to determine the metastatic status of the complete LN and therefore improve staging.  相似文献   
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