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Coronary artery bypass grafts: visualization with MR imaging   总被引:1,自引:0,他引:1  
Gomes  AS; Lois  JF; Drinkwater  DC  Jr; Corday  SR 《Radiology》1987,162(1):175
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Survival of patients with surgically treated malignancy may be adversely affected by blood transfusion. Immune suppression due to transfusion has been implicated but remains unproven. We conducted a study of 240 patients with squamous cell carcinoma of the larynx undergoing laryngectomy to assess the effect of per-operative blood transfusion on survival.  相似文献   
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The mapping of 5-HT2 receptors in the brain using functional imaging techniques has been limited by a relative lack of selective radioligands. Iodine-123 labelled 4-amino-N-[1-[3-(4-fluorophenoxy)propyl]-4-methyl-4-piperidinyl]-5-iodo-2-methoxybenzamide (123I-5-I-R91150 or123I-R93274) is a new ligand for single-photon emission tomography (SPET), with high affinity and selectivity for 5-HT2A receptors. This study reports on preliminary123I-5-I-R91150 SPET, wholebody and blood distribution findings in five healthy human volunteers. Maximal brain uptake was approximately 2% of total body counts at 180 min post injection (p.i.). Dynamic SPET sequences were acquired with the brain-dedicated, single-slice multi-detector system SEM-810 over 200 min p.i. Early peak uptake (at 5 min p.i.) was seen in the cerebellum, a region free from 5HT2A receptors. In contrast, radioligand binding in the frontal cortex increased steadily over time, up to a peak at approximately 100–120 min p.i. Frontal cortex-cerebellum activity ratios reached values of 1.4, and remained stable from approximately 100 min p.i. onwards. Multi-slice SPET sequences showed a pattern of regional variation of binding compatible with the autoradiographic data on the distribution of 5-HT2A receptors in (cerebral cortex>striatum>cerebellum). These findings suggest that123I-5-I-R91150 may be used for the imaging of 5-HT2A receptors in the living human brain with SPET.  相似文献   
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This article discusses the problems facing nuclear medicine in the coming decade and outlines the areas in which new developments or expansion can be expected. The questions considered include legislative requirements, the need to educate the public and the medical profession on the strengths of nuclear medicine, approaches to cost-benefit analysis, and development of new technologies and new radiopharmaceuticals. There is also an evaluation of expansion in nuclear medicine using both existing methodology and new methodologies.  相似文献   
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A. May  C. Ell   《Digestive and liver disease》2006,38(12):932-938
Push-and-Pull enteroscopy/Double balloon enteroscopy (PPE/DBE) allows enteroscopy of the entire small bowel, or at least a substantial part of it. The complication rate is acceptably low. Severe complications such as pancreatitis and perforation were encountered in the literature in approximately 1% of all diagnostic PPE/DBEs. It can be expected that the complication rate of therapeutic PPE/DBEs is higher, comparable with the conventional endoscopy. The diagnostic yield is high, at approximately 75%, as is the therapeutic yield. The option of carrying out endoscopic therapy (in approximately 40%–50% of cases in the Western hemisphere) is an important aspect. Angiodysplasias are the main bleeding source, at least in Western countries. Using the PPE/DBE device, endoscopic treatments such as endoscopic hemostasis using injection and argon plasma coagulation, polypectomy, endoscopic resection, balloon dilation, and foreign-body extraction have become feasible even in the small intestine and can generally be performed safely and without relevant technical problems. Medical therapy can be started in up to 20% of cases—e.g., after a new or changed diagnosis of Crohn's disease. Surgical therapy is required in 10–20% of cases, due to malignant tumors or complex stenoses, for example. The main indication is mid-gastrointestinal bleeding.  相似文献   
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