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51.
Meckel's diverticulum is the most common congenital gastrointestinal anomaly. Axial torsion of the diverticulum is rare and may produce nonspecific abdominal signs and symptoms. We describe a case of torsion of a Meckel's diverticulum that was noted as a pelvic mass on CT images. Received: 9 April 2001/Accepted: 15 August 2001  相似文献   
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Extraneural relapse of medulloblastoma is an uncommon event which has typically been associated with a fatal outcome. We present a case of a 2 1/2-year-old male who developed extensive bone marrow and bone metastases 19 months after diagnosis and treatment of a medulloblastoma. This patient was successfully treated with a sequentially scheduled combination of vincristine, cyclophosphamide, and doxorubicin and remained free of disease for more than 5 years from the time of relapse.  相似文献   
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1. Mechanisms involved in the plasma extravasation observed following thermal injury of rat dorsal skin were investigated. 2. Heat applied to the dorsal skin of anaesthetized rats by a temperature-controlled skin heater (1 cm diameter) for 5 min induced temperature-dependent plasma protein extravasation a. 48–48.5°C, measured for up to 4 h following initiation of heat. 3. A tachykini. NK1 receptor antagonist (SR140333), a bradykinin B2 receptor antagonist (HOE 140) and a cyclooxygenase inhibitor (indomethacin), when given as cotreatments prior to the selected measurement period, markedly suppressed oedema formation observed over 0–1 h (P < 0.05) but not that observed over 3–4 h after injury. 4. These results indicate that although neurokinins, bradykinin and cyclo-oxygenase products may be important for the early response to thermal injury, they do not appear to play an important role in the ongoing oedem. response. 5. Neutrophils accumulate at the inflammatory site by 4h after thermal injury. Therefore, the effect of depletion of circulating neutrophils by a rat anti-neutrophil antiserum on oedema formation over the 0–4 h period was investigated. The results show that oedema formation was similar in control and antineutrophil-treated rats. 6. In conclusion, the data from the present study indicate that neuropeptides as well as other vasoactive mediators play a role in the acute plasma extravasation observed after thermal injury, but not in the ongoing inflammatory injury. Neutrophils, despite their presence at sites of thermal injury, do not appear to be involved in mediating the oedema formation observed up to 4 h after thermal injury.  相似文献   
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Thrombopoietin (Tpo), the ligand for c-mpl, has been shown to be the principal regulator of megakaryocytopoiesis and platelet production. The ability of Tpo to potently stimulate the growth of committed megakaryocyte (Mk) progenitor cells has been studied in detail. Murine fetal liver cells, highly enriched in primitive progenitors, have been shown to express c-mpl, but little is known about the ability of Tpo to stimulate the growth and differentiation of primitive multipotent bone marrow (BM) progenitor cells. Here, we show that Tpo alone and in combination with early acting cytokines can stimulate the growth and multilineage differentiation of Lin- Sca-1+ BM progenitor cells. In particular, Tpo potently synergized with the ligands for c-kit (stem cell factor [SCF]) and flt3 (FL) to stimulate an increase in the number and size of clones formed from Lin- Sca-1+ progenitors. When cells were plated at 1 cell per well, the synergistic effect of Tpo was observed both in fetal calf serum-supplemented and serum-depleted medium and was decreased if the addition of Tpo to cultures was delayed for as little as 24 hours, suggesting that Tpo is acting directly on the primitive progenitors. Tpo added to SCF + erythropoietin (Epo)-supplemented methylcellulose cultures potently enhanced the formation of multilineage colonies containing granulocytes, macrophages, erythrocytes, and Mks. SCF potently enhanced Tpo-stimulated production of high-ploidy Mks from Lin- Sca-1+ progenitors, whereas the increased growth response obtained when combining Tpo with FL did not translate into increased Mk production. The ability of Tpo and SCF to synergistically enhance the growth of Lin- Sca-1+ progenitors was predominantly observed in the more primitive rhodamine 123(lo) fraction. Tpo also enhanced growth of Lin- Sca-1+ progenitors when combined with interleukin-3 (IL-3) and IL-11 but not with IL-12, granulocyte colony-stimulating factor, granulocyte-macrophage colony- stimulating factor, or Epo. Epo, which has high homology to Tpo, was unable to stimulate the growth of Lin- Sca-1+ progenitors alone or in combination with SCF or FL, suggesting that c-mpl is expressed on more primitive stages of progenitors than the Epo receptor. Thus, the present studies show the potent ability of Tpo to enhance the growth of primitive multipotent murine BM progenitors in combination with multiple early acting cytokines and documents its unique ability to synergize with SCF to enhance Mk production from such progenitors.  相似文献   
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Bender B  Korn A  Ioanoviciu SD  Horger M  曹毅媛   《放射学实践》2012,27(11):1282-1283
肠脂垂为沿结肠带两侧分布的许多小突起,长度0.5-5.0cm,  相似文献   
60.
Tight glycemic control in the ICU has been shown to reduce mortality in some but not all prospective randomized control trials. Confounding the interpretation of these studies are differences in how the control was achieved and underlying incidence of hypoglycemia, which can be expected to be affected by the introduction of continuous glucose monitoring (CGM). In this issue of Critical Care, a consensus panel provides a list of the research priorities they believe are needed for CGM to become routine practice in the ICU. We reflect on these recommendations and consider the implications for using CGM today.Continuous glucose control in the ICU: report of a 2013 Round Table meeting, published in this issue of Critical Care[1], summarizes the discussion and recommendations of a round table meeting on the management of blood glucose levels in the ICU. The self-selected panel of authors recommends eight areas where it believes research is needed, beginning with head-to-head comparisons of different continuous glucose monitoring (CGM) devices and ending with randomized controlled studies validating closed-loop insulin delivery.Appropriately, the recommendations focus on what is needed to advance CGM into the ICU and do not address whether tight glycemic control is beneficial or what the appropriate target range should be. Nonetheless, the answers to these questions will impact the importance of the recommendations. Of the prospective randomized controlled studies performed to date, many have failed to show a clinical benefit to tight glycemic control (TGC) - including our own study in children less than 3 years of age following cardiac surgery [2]. Our current study assessing the possible benefit of TGC in hyperglycemic critically ill children with cardiovascular and/or respiratory failure (NCT01565941) seeks to answer the question whether control in the target range 80 to 110 mg/dL results in better outcomes than control in the 150 to 180 mg/dL target range. Clearly, if the 80 to 110 mg/dL range proves beneficial, the need to introduce CGM into the ICU will be paramount as this target range is difficult to achieve without increasing the incidence of hypoglycemia. This may be less important if the 150 to 180 mg/dL range is shown to be equally effective. It is possible that TGC with CGM will reduce glucose variability irrespective of the target range, and the panel’s recommendations appropriately call for study of the effect of different treatment algorithms on this metric. However, it should be noted that the evidence the authors cite supporting the importance of glycemic variability [3] is based on retrospective analysis, which cannot be used to infer causality.Still, the question remains as to how best to manage glucose levels in critically ill patients today. Putting aside whether control in a low target range is better than in a higher range, or whether a reduction in glucose variability per se improves clinical outcomes, there are low and high glucose levels that would be treated today in virtually every ICU. Every effort needs to be made to avoid these ends of the spectrum. To this end, one might ask whether CGM devices should be used in the ICU now. One can correctly infer from the recommendations that there have been no head-to-head comparisons of different CGM devices, and that the trends reported have also not been validated. Likewise, investigators who have established insulin protocols at their institutions might ask whether the protocols need to be re-evaluated given the marked differences in insulin recommendations noted by Wilson and colleagues [4] in work highlighted by the consensus panel. Our own review of TGC protocols concurs with that of Wilson and colleagues [4] in that we also noted substantive differences among the existing protocols [5]; however, we concluded that virtually all the protocols could be expected to achieve and maintain their desired target glucose ranges and each could be reasonably expected to benefit from the use of CGM devices.  相似文献   
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