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Dipyridamole thallium scanning (DTS) is an imaging technique with good sensitivity for coronary artery disease (CAD). The purpose of this study was to compare the haemodynamic courses and the correlation between pulmonary capillary wedge pressure (PCWP) and central venous pressure (CVP) in patients with normal DTS (Group 1: n = 12) with those whose scans demonstrated CAD (Group2: n = 11). Haemodynamic profiles were obtained prior to anaesthesia and at several times during surgery. The haemodynamic courses in both groups were similar with significant decreases in cardiac index, stroke index, and left ventricular stroke work index during aortic cross-clamping compared with values prior to anaesthesia. There were no significant changes in PCWP and CVP throughout the study. The correlations between PCWP and CVP were significant in both groups as were the correlations between the changes in PCWP and the changes in CVP observed at the time of cross-clamping. These correlations all had large standard errors of the estimate, however, making it impossible to predict the PCWP from the CVP with precision. It is concluded that, in a limited study population, an abnormal DTS did not identify patients in whom the PCWP and CVP correlated poorly during abdominal aortic aneurysmectomy.  相似文献   
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Central serotonin (5-HT) metabolism during embryogenesis and a 3-day post-hatching period was analyzed using high performance liquid chromatography in the directly developing frog, Eleutherodactylus coqui. This anuran bypasses the free-swimming larval stage and embryos hatch as miniature frogs in the adult phenotype. During embryogenesis and for a short time immediately after hatching, male E. coqui provide paternal care by brooding and guarding eggs/embryos to prevent desiccation and predation. Serotonin and its catabolite, 5-HIAA, were measured from whole brain during embryogenesis and at 3 days post-hatch to identify critical periods in 5-HT development and to determine the relationship between 5-HT and life history events such as hatching and frog dispersal from the nest site. Serotonergic activity was highest during the early-mid embryonic stages as indicated by the ratio of 5-HIAA/5-HT, a general indicator of turnover and metabolism. There were significant increases in tissue concentrations of 5-HT during the latest or terminal embryonic stage, just prior to hatching, and also at 3 days post-hatch, shortly before neonates disperse into the rainforest. These two increases probably represent different functional requirements during development. The first may occur as a result of the surge of development in the 5-HT system during late embryogenesis that occurs in E. coqui and the second may be from the increase demand in sensory and motor neural development required before dispersal from the nest site.  相似文献   
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BACKGROUND AND PURPOSE: The appropriate application of 3-D CRT and IMRT for HNSCC requires a standardization of the procedures for the delineation of the target volumes. Over the past few years, two proposals--the so-called Brussels guidelines from Grégoire et al., and the so-called Rotterdam guidelines from Nowak et al.--emerged from the literature for the delineation of the neck node levels. Detailed examination of these proposals however revealed some important discrepancies. MATERIALS AND METHODS: Within this framework, the Brussels and Rotterdam groups decided to review their guidelines and derive a common set of recommendations for delineation of neck node levels. This proposal was then discussed with representatives of major cooperative groups in Europe (DAHANCA, EORTC, GORTEC) and in North America (NCIC, RTOG), which, after some additional refinements, have endorsed them. The objective of the present article is to present the consensus guidelines for the delineation of the node levels in the node-negative neck. RESULTS AND CONCLUSIONS: First a short discussion of the discrepancies between the previous Brussels and the Rotterdam guidelines is presented. The general philosophy of the consensus guidelines and the methodology used to resolve the various discrepancies are then described. The consensus proposal is then presented and representative CTVs that are consistent with these guidelines are illustrated on CT sections. Last, the limitations of the consensus guidelines are discussed and some concerns about the direct applications of these guidelines to the node-positive neck and the post-operative neck are described.  相似文献   
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PURPOSE: To explore the safety and therapeutic activity of combination anti-B-cell monoclonal antibody therapy in non-Hodgkin's lymphoma (NHL). PATIENTS AND METHODS: Twenty-three patients with recurrent B-cell lymphoma received anti-CD22 epratuzumab 360 mg/m(2) and anti-CD20 rituximab 375 mg/m(2) monoclonal antibodies weekly for four doses each. Sixteen patients had indolent histologies (15 with follicular lymphoma) and seven had aggressive NHL (all diffuse large B-cell lymphoma [DLBCL]). Indolent patients had received a median of one (range, one to six) prior treatment, with 31% refractory to their last therapy and 81% with high-risk Follicular Lymphoma International Prognostic Index scores. Patients with DLBCL had a median of three (range, one to eight) prior regimens (14% resistant to last treatment) and 71% had high intermediate-risk or high-risk International Prognostic Index scores. All patients were rituximab na?ve. RESULTS: Treatment was well tolerated, with toxicities principally infusion-related and predominantly grade 1 or 2. Ten (67%) patients with follicular NHL achieved an objective response (OR), including nine of 15 (60%) with complete responses (CRs and unconfirmed CRs). Four of six assessable patients (67%) with DLBCL achieved an OR, including three (50%) CRs. Median time to progression for all indolent NHL patients was 17.8 months. CONCLUSION: The full-dose combination of epratuzumab with rituximab was well tolerated and had significant clinical activity in NHL, suggesting that this combination should be tested in comparison with single-agent treatment.  相似文献   
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In brief: To determine what public and individual efforts might reduce bicycling accidents and injuries, a survey was conducted during the primary cycling months (April through September) in Boulder, Colorado. Of 253 patients (87 women, 166 men, average age 22) treated for injuries in bicycling accidents, almost 30% of the accidents were caused by gravel, and nearly half involved a motor vehicle. The most frequent types of injury were abrasions, contusions, lacerations, and fractures. The survey results confirm the need for adequate head protection, satisfactory lighting, and increased awareness on the bicyclist's part. In addition, improved street maintenance will drastically reduce the number of cycling injuries and accidents.  相似文献   
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