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21.
Mechanical airway obstruction secondary to retropharyngeal bleeding is rare. In most cases such a complication is described after head and neck trauma. Complicating factors include anticoagulant therapy, tumour, aneurysm, infection or major cervical spine injury. A precise initial diagnosis is necessary to avoid a life-threatening situation. Lateral X-ray and computed tomography is essential for safe management. Treatment depends upon size of the haematoma as well as the clinical course of the patient. Smaller haematomas may be observed. Lager haematomas and those that fail to reabsorb should undergo drainage.   相似文献   
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OBJECTIVES: to report our experience with hybrid vascular procedures in patients with pararenal and thoracoabdominal aortic pathologies. METHODS: 68 patients were treated for thoracoabdominal aortic pathologies between October 1999 and February 2004; 19 patients (16 men; mean age 68, range 40-79) with high risk for open thoracoabdominal repair were considered to be candidates for combined endovascular and open repair. Aortic pathologies included five thoracoabdominal Crawford I aneurysms, one postdissection expanding aneurysm, three symptomatic plaque ruptures (Crawford IV), five combined thoracic descending and infrarenal aneurysms with a healthy visceral segment, three juxtarenal or para-anastomotic aneurysms, and two patients with simultaneous open aortic arch replacement and a rendezvous maneuver for thoracic endografting. Commercially available endografts were implanted with standardized endovascular techniques after revascularization of visceral and renal arteries. RESULTS: Technical success was 95%. One patient developed a proximal type I endoleak after chronic expanding type B dissection and currently is waiting conversion. Nine patients underwent elective, five emergency and five urgent (within 24 h) repair. 17 operations were performed simultaneously, and 2 as a staged procedure. Postoperative complications include two retroperitoneal hemorrhages, and one patient required long-term ventilation with preexisting subglottic tracheal stenosis. Thirty-day mortality was 17% (one multiple organ failure, one secondary rupture after open aortic arch repair, one myocardial infarction). Paraplegia or acute renal failure were not observed. Total survival rate was to 83% with a mean follow-up of 30 months. CONCLUSIONS: Midterm results of combined endovascular and open procedures in the thoracoabdominal aorta are encouraging in selected high risk patients. Staged interventions may reduce morbidity.  相似文献   
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Purpose To determine the systemic effects of local fibrinolytic therapy with low-dose recombinant tissue-type plasminogen activator (rt-PA). Methods Ten patients received intrathrombal infusion of 20 mg rt-PA and heparin for local thrombolysis and had subsequent percutaneous transluminal angioplasty (PTA). Eight controls underwent PTA and received heparin alone. We measured t-PA, D-Dimer, and fibrinogen levels before, directly after, and 20, 40, and 60 min and 24 hr after therapy. Results In the thrombolysis group the t-PA level peaked immediately after infusion and then declined within 1 hr. D-Dimer increased and remained elevated, whereas in the control group only t-PA levels increased, and only after 24 hr. Fibrinogen remained within the normal range in both groups. Eight of ten patients in the thrombolysis group and seven of eight with PTA had clinical improvement after the procedure. Conclusions The increase in D-Dimer in the rt-PA group indicates a good local fibrinolytic effect. The fact that fibrinogen levels remained unchanged indicates that there is a lack of systemic fibrinogenolysis.  相似文献   
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The temporal structure of spike trains recorded from optic fibers and single units of the lateral geniculate nucleus (LGN) and primary visual cortex of the cat was studied with a novel method of inter-spike interval analysis. ON type relay cells of the LGN exhibited a multimodal interval distribution preferring a distinct interval (fundamental interval) and its multiples during the sustained light response, whereas most OFF cells showed a broad, unimodal distribution. The general pattern of the interval distribution was relatively independent of stimulus size and contrast and the degree of light adaptation. Simultaneously recorded S-potentials originating from the retinal input generally produced only a single peak at the fundamental interval length. Therefore, the multimodal interval distribution of LGN cells seems to be a result of intra-geniculate inhibition. Cortical cells also showed a weak tendency to fire with spike intervals similar to LGN cells. Therefore, the regular firing pattern observed at peripheral stages of the visual pathway can persist at higher levels and might promote the occurrence of oscillatory activity.  相似文献   
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Activation with lipopolysaccharide induces macrophages to produce the enzymes arginase and nitric oxide (NO) synthase. Both enzymes use as a substrate the amino acid L-arginine, which can be either hydrolyzed by arginase to urea and ornithine or oxidized by NO synthase to NO and citrulline. NO is important in the bactericidal and cytotoxic activities of macrophages. An equivalent functional role of arginase and its products is not known. We tested the induction of arginase in bone marrow-derived macrophages by endogenous mediators that are known to induce NO synthase, such as interferon-γ (IFN-γ), or suppress the induction of this enzyme, such as interleukin (IL)-4, IL-10, and prostaglandin E2 (PGE2). We find that PGE2 and the TH2 cytokines IL-4 and IL-10 are potent inducers of arginase. In contrast, the TH 1 cytokine IFN-γ does not induce arginase. Simultaneous application of both types of mediators leads to reduced induction of both arginase and NO synthase. Exposure of macrophage cultures to inducers of NO synthase exhausts their ability to respond subsequently to inducers of arginase. Conversely, exposure of the cells to inducers of arginase exhausts their ability to respond subsequently to inducers of NO synthase. The results are consistent with a competition of both enzymes for their substrate, L-arginine, with a reciprocal inhibition in the induction of both enzymes, or a combination of both phenomena. The enzymes NO synthase and arginase appear to define two alternate functional states of macrophages, induced by TH 1 and TH 2 cytokines, respectively.  相似文献   
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Acute ischaemia of the vertebrobasilar circulation leads to a variety of clinical manifestation and is mostly due to cardiogenic or artery-to-artery embolism. We describe four neurological emergency situations involving vertebrobasilar artery aclusion of other origins: basilar migraine, extrinsic compression by rheumatoid inflammatory tissue, generalized vasculitis in subacute rheumatic fever and basilar artery dissection. The differential diagnosis of acute vertebrobasilar artery occlusion may have an important impact on patient management.  相似文献   
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A cDNA encoding a transmembrane 140 kDa isoform of the neural cell adhesion molecule, NCAM, was transfected into the rat glioma cell line BT4Cn. Transfectants with a homogeneously high expression of NCAM-B showed a decreased capacity for penetration of an artificial basement membrane when compared to cells transfected with expression-vector alone or untransfected cells. However, when injected subcutaneously into nude mice, both NCAM expressing cells and control cells produced invasive tumors. Nude mice injected with NCAM positive cells developed tumors with slower growth rates as compared to those induced by NCAM negative cells. This implies that NCAM may not only be involved in adhesive and motile behaviour of glioma cells, but also in their growth regulation.  相似文献   
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