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991.
A 70-year-old male with a superficial granulomatous ulcer is reported. Histopathological findings were the same as those described for superficial granulomatous pyoderma, a recognized variant of classic pyoderma gangrenosum. The differences between pyoderma gangrenosum and its variant superficial granulomatous pyoderma are highlighted.  相似文献   
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Ketamine, an N-methyl-D-aspartate (NMDA) receptor antagonist, is used as a general pediatric anesthetic. Recent data suggest that anesthetic drugs may cause neurodegeneration during development. The purpose of this study was to determine the robustness of ketamine-induced developmental neurotoxicity using rhesus monkey frontal cortical cultures and also to determine if dysregulation of NMDA receptor subunits promotes ketamine-induced cell death. Frontal cortical cells collected from the neonatal monkey were incubated for 24 h with 1, 10, or 20 microM ketamine alone or with ketamine plus either NR1 antisense oligonucleotides or the nuclear factor kB translocation inhibitor, SN-50. Ketamine caused a marked reduction in the neuronal marker polysialic acid neural cell adhesion molecule and mitochondrial metabolism, as well as an increase in DNA fragmentation and release of lactate dehydrogenase. Ketamine-induced effects were blocked by NR1 antisenses and SN-50. These data suggest that NR1 antisenses and SN-50 offer neuroprotection from the enhanced degeneration induced by ketamine in vitro.  相似文献   
996.
BACKGROUND: Because the Rh antigens E (Rh3) and c (Rh4) are relatively immunogenic, it has been suggested that R1R1 (E-, c-) patients who present with anti-E alone receive prophylactic c- (Rh: -4) red cell transfusions. STUDY DESIGN AND METHODS: To determine the utility of this approach, the transfusion records of 100 consecutive R1R1 patients with anti-E identified over a 6-year period were reviewed. RESULTS: Thirty-two (32%) had anti-c concurrent with anti-E. Twenty-seven of the 68 patients who presented with anti-E alone received random (i.e., not typed for c [Rh4]) red cell transfusions. Five (18.5%) of the 27 subsequently developed anti-c 13 to 193 days (mean, 50) after transfusion of 2 to 14 (mean, 8) red cell units. None of the five had clinical evidence of hemolysis that could be attributed to a delayed hemolytic transfusion reaction. Twenty-two (81.5%) of the 27 failed to develop anti-c even after transfusion of 1 to 41 (mean, 9; median, 7) red cell units. CONCLUSION: The overall rate of immunization to c (Rh4) antigen in R1R1 patients with anti-E was 37 percent. Production of anti- c following transfusion to R1R1 patients with anti-E occurred in 18.5 percent of the cases in this series, which could have been avoided by the prophylactic use of R1R1 (E-, c-) blood for transfusion. The prophylactic use of c- (Rh: -4) blood in this patient population may be justified by the high immunization rate and the potential risk of delayed hemolytic transfusion reaction.  相似文献   
997.
Marrow graft failure is a significant cause of morbidity following bone marrow transplantation. A case is reported of marrow graft failure due to neutrophil antibodies. A 13-year-old girl with a large granular lymphocytosis and chronic neutropenia was treated with granulocyte transfusions prior to undergoing a transplant with bone marrow from a partially matched, unrelated donor. Following the transplant, a bone marrow biopsy showed engraftment of donor myeloid cells, but the recipient remained neutropenic. Testing of the serum for neutrophil antibodies found that the recipient's serum had a high-titer neutrophil antibody. Immunoprecipitation studies using the marrow recipient's serum and 125I surface-labeled neutrophils showed that the antibody reacted to the neutrophil-specific antigen NB1. Phenotyping of neutrophils from the marrow donor found that they expressed NB1 antigen, and, in a crossmatch assay, the recipient's serum reacted with donor neutrophils. Despite treatment with granulocyte-macrophage– colony-stimulating factor, the marrow transplant recipient remained neutropenic and died of polymicrobial sepsis and aspergillosis 38 days after the transplant. The presence of high-titer antibodies to neutrophil-specific antigen NB1 in this patient following transplant likely prevented the recovery of her peripheral blood neutrophils and contributed to her death.  相似文献   
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The purpose of this study is to assess the impact of a primary health care strengthening intervention on bypassing behavior in Albania, a middle-income country that has experienced substantial structural changes that affect PHC and where bypassing among health care clients is common. The intervention aimed to improve the quality of health care in low-level facilities through improved availability and use of health information, the adoption of clinical practice guidelines, and provider training. The study employs a quasi-experimental research design to evaluate the impact of the intervention on health care utilization. The survey findings suggest that the pilot areas outperformed the control areas with respect to a number of key population-based indicators of health care utilization. For example, in the 2-year period between December 2002 and December 2004, bypassing for treatment of simple acute health problems during the month prior to the survey decreased by 47%, and the percentage of chronically ill health care clients who utilized PHC facilities for treatment in the month prior to the survey increased by 29%. These differences, which are statistically significant at the 10% level or better, suggest that the improved performance in the pilot areas is attributable to the intervention.  相似文献   
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