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71.
Diagnosis and staging of pancreatic cancer: comparison of mangafodipir trisodium-enhanced MR imaging and contrast-enhanced helical hydro-CT 总被引:17,自引:0,他引:17
Schima W Függer R Schober E Oettl C Wamser P Grabenwöger F Ryan JM Novacek G 《AJR. American journal of roentgenology》2002,179(3):717-724
OBJECTIVE: The purpose of this study was to compare mangafodipir trisodium-enhanced MR imaging performed with a phased array coil and contrast-enhanced single-detector helical CT for accuracy in the detection and local staging of pancreatic adenocarcinoma and in the differentiation between cancer and focal pancreatitis. SUBJECTS AND METHODS: Forty-two patients with suspected pancreatic masses underwent contrast-enhanced helical CT and mangafodipir trisodium-enhanced MR imaging at 1.5 T. The images were assessed for the presence or absence of tumors; characterization of masses; and presence of vascular invasion, lymph node metastases, or liver metastases. Imaging findings were correlated with findings at laparotomy, laparoscopy, biopsy, or follow-up. RESULTS: Focal masses were present in 36 patients (cancer, n = 26; focal pancreatitis, n = 7; other, n = 3). The sensitivity for lesion detection of MR imaging was 100% and of CT, 94%. Two small malignant lesions were missed on CT. For the diagnosis of tumor nonresectability, the sensitivity of MR imaging and CT was 90% and 80%, respectively. Liver metastases were missed on MR imaging in one of the eight patients and on CT in four. For differentiation between adenocarcinoma and nonadenocarcinoma, the sensitivity of MR imaging was 100% (positive predictive value, 90%; negative predictive value, 100%), and the sensitivity of CT was 92% (positive predictive value, 80%; negative predictive value, 67%). Receiver operating characteristic analysis revealed that the mean area under the curve for MR imaging was 0.920 and for CT, 0.832 (not significant). CONCLUSION: Mangafodipir trisodium-enhanced MR imaging is as accurate as contrast-enhanced helical CT for the detection and staging of pancreatic cancer but offers improved detection of small pancreatic metastases and of liver metastases compared with CT. 相似文献
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G Rooth U Ewald F Caligara 《Scandinavian journal of clinical and laboratory investigation》1985,45(5):393-396
It is shown how the anaerobic energy production of the skin may be calculated from a transcutaneous PCO2 curve obtained at 37 degrees C during arterial occlusion. Thirty healthy volunteers were studied three times. The inter-individual differences in estimated ATP production were highly significant, but the intra-individual ones were not. The grand mean of the triplicate experiments of all the 30 subjects was an ATP production rate of 0.33 mmol X l-1 X min-1. Assuming no initial metabolic acidosis or alkalosis, the estimated mean extracellular fluid pH was 7.33 before and 7.26 after 4 min of stasis. 相似文献
74.
Ewald Frick 《Journal of molecular medicine (Berlin, Germany)》1962,40(3):152-153
Zusammenfassung Es werden Untersuchungen mit einem Kaninchenserum gegen normale Liquoreiweißkörper vorgelegt. Im Vergleich mit einem Immunserum gegen normale Serumproteine ließ sich eine weitgehende Übereinstimmung der Befunde feststellen, insbesondere war eine liquorspezifische Eiweißkomponente nicht nachzuweisen. 相似文献
75.
The specific aspects of the respiratory cycle during mechanical ventilation that allow for optimum gas exchange are still controversial. To further clarify the relationship of inspiratory:expiratory ratio and positive end expiratory pressure to optimum ventilation and oxygenation, five premature lambs with severe hyaline membrane disease were ventilated with volume-present infant ventilators at I:E ratios of 1:4 and 1:1 and PEEP levels of 0, 5, and 10 cm H2O. For each I:E ratio/PEEP combination, pH, Pao2, PaCO2, PAO2, PACO2, peak inspiratory pressure, mean inspiratory pressure, and mean airway pressure were measured and compared. Optimum ventilation and oxygenation were related to MAP, but not to I:E ratio, PIP, or MIP. As MAP increased from 6 to 14 cm H2O, progressive improvement in Pao2, PaCO2 (A-a) DO2 and (a-A) DCO2 was evident. Above 14 cm H2O, there was progressive deterioration in these measurements. There was also a direct relationship between MAP and mean pleural pressure. These results indicate that during mechanical ventilation there is an optimum MAP at which gas exchange is best. Since MAP changes with any change in PIP, PEEP, or I:E ratio, it provides a useful composite measure of all pressures transmitted to the airways by the ventilator. 相似文献
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OBJECTIVE: This article reviews the concept of difficult-to-treat depression and outlines some principles of pharmacologic management. METHODS: The authors conducted a MEDLINE review for the years 1999 to 2004, using the key words refractory, resistant, and difficult-to-treat depression. RESULTS: Only a small body of evidence-based literature exists to guide the management of difficult-to-treat depression. Nevertheless, clinicians often need to make treatment decisions in the absence of clear data. Depression should not be considered resistant, refractory, or difficult to treat in the absence of trials in which an appropriate drug is given in a dosage and duration sufficient to produce a response. Nevertheless, inadequate antidepressant trials are a relatively common phenomenon. Nonresponse may also result from pharmacokinetic or pharmacogenomic factors. Principals for assessing difficult-to-treat depression include preventing pseudo-resistant cases, recognizing that finding the best treatment option is a process, developing a systematic step-by-step approach, and preserving hope. A review of the literature demonstrated a two-step approach for managing difficult-to-treat depression. The first step is to evaluate for factors that contribute to nonresponse, such as comorbid medical and psychiatric conditions. The second step involves using the four classical strategies for enhancing antidepressant efficacy: optimization, augmentation, combination, and switching. CONCLUSION: Advances have been made in the treatment of depression, but a great deal more research needs to be done. It is hoped that new alternatives and promising developments in methods will contribute to the improved management of what we now call difficult-to-treat depression. 相似文献
80.
Pyomyositis is a common disease in the tropics that is reported with increasing frequency in the United States. We describe an unusually fulminant, fatal case in a previously healthy adolescent male. This case illustrates the clinical progression of pyomyositis from localized muscle infection to disseminated disease, and highlights the importance of considering this rare diagnosis in any stage of occult sepsis. 相似文献