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In a preterm infant, chest tubes were inserted for treatment of bilateral pneumothoraces. Hemorrhagic pericardial effusion with cardiac tamponade developed, probably resulting from traumatic injury by the left chest tube. The infant survived due to timely diagnostic and therapeutic intervention. No recurrence of pericardial effusion was seen and follow-up showed normal psychomotor development. 相似文献
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Edo O. Schraa Sylvia N. Schotman Marcel Scheringa Mohamed R. Daha Richard L. Marquet Jan N.M. IJzermans 《Xenotransplantation》1996,3(4):321-327
Abstract: Discordant grafting, the best alternative for future transplantation, is hampered by hyperacute rejection (HAR). Yet, there might be a difference in susceptibility to HAR between organs. In allogeneic transplantation the liver is less sensitive to antibody mediated rejection. In order to investigate whether this might also occur in discordant xenotransplantation, we performed orthotopic liver transplantation (OLT) from Dunkin Hartley guinea pigs (GP) to Brown Norway rats. Five groups were studied. In group 1, untreated controls survived for 1.5 to 4.5 hr (n = 5). In order to investigate how long a recipient could survive without a functioning graft, animals in group 2 underwent total hepatectomy (tHx) with portal-caval shunt, resulting in survival times ranging from 2 to 7 hr (n = 5). Antibody reduction by splenectomy (Spx) on day -5 (group 3) did not increase survival time (1 to 2 hr, n = 5). Complement depletion by cobra venom factor (CVF) prolonged the survival time up to 35 hr (n = 7, group 4). One animal lived for 4 days. The combined treatment of Spx and CVF resulted in similar survival times as following CVF alone, ranging from 2 hr to 6 days (n = 6, group 5). Surprisingly, none of the grafts in either of the groups showed classical signs of hyperacute rejection, like hemorrhage, edema, or obstruction of capillaries and veins as seen in the GP to rat heart transplantation model. Also liver enzyme parameters indicated no ongoing rejection. Immunohistochemistry revealed deposits of complement factors C1q, C3, and C6 on Kupffer cells but not on endothelial cells. These results indicate that, in this particular discordant model, the liver is not affected by the classical features of HAR. The beneficial effect of CVF on recipient survival therefore may rather be due to inhibition of a lethal secondary response evoked by the graft than to inhibition of HAR. 相似文献
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Synthesized and directly acquired spin-echo images were compared in order to assess the validity of magnetic resonance (MR) image synthesis as a method enabling retrospective formation of images by interactive manipulation of scan parameters. Synthetic images subjectively compared favorably in both accuracy and precision with acquired images when formed for the same values of echo (TE) and repetition times (TR) and for interpolated and extrapolated values of both TE and TR. Plots of synthetic and acquired signals within the same pixel sectors quantitatively showed comparable values for several regions of interest in the brain. Percent error and noise-normalized differences between acquired and synthetic images were tested as a quantitative measure of accuracy. Percent error was consistently less than 5% for brain parenchyma, and synthetic signals were accurate to within four times the noise level at acquisition. The apparent signal-to-noise ratio of synthetic images was comparable, superior, or inferior to similar acquired images, depending on the values of TE and TR. Total acquisition time required for synthetic formation of images for arbitrary values of TE and TR was equivalent to that of a single direct acquisition with a TR of 2,500 msec. 相似文献
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During a 20-month period, fractures of the clivus occurring after craniocerebral trauma were diagnosed with computed tomography (CT) in 11 patients. Five patients had longitudinally oriented fractures; these were fatal in four patients due to either vertebral-basilar artery occlusion, brain stem trauma, or both. Six other patients had transversely oriented fractures that extended through the carotid canal and petrous temporal bone. While less frequently contributing directly to mortality, transverse fractures were also associated with cerebrospinal fluid leaks (two patients) and a cavernous sinus-carotid fistula (one patient). They were not as frequently associated with Horner syndrome or cranial nerve deficits as suggested in the current literature. This retrospective evaluation reveals two distinct injury patterns that demonstrate a difference in related morbidity and mortality. 相似文献
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