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61.
Increased fibrinolytic activity is a well recognized constant finding observed during cardiopulmonary bypass (CPB). The purpose of the present work was to study and estimate the factors involved in the plasminogen activation and prekallikrein-kallikrein systems in a population of adult patients undergoing open heart surgery with CPB. Plasminogen activator activity determinations with a fibrinolytic method as well as plasminogen activation and prekallikrein-kallikrein determinations with synthetic substrates were carried out. Our results indicate that no active fibrinolysis but a fibrinolytic potential, similar to that observed in blood obtained after venous occlusion, can be demonstrated in circulating plasma during CPB. This fibrinolytic potential is related to the presence of vascular plasminogen activator released from endothelial cells by the CPB stimulus. 相似文献
62.
Ocular symptoms in internal carotid artery occlusion] 总被引:1,自引:0,他引:1
The internal carotid artery occlusion causing an insufficiency of the cerebral circulation manifests itself--besides the neurological symptoms--by disorders of the visual organ. One can distinguish among them early, functional symptoms in the form of transient unilateral hemianopia on the side opposite to the occluded carotid artery and the attacks of transient amblyopia. Signs of fixed ischaemia of the eye ball appear afterwards in the form of oculomotor and pupillary disturbances, neovascularization of the iris, disturbances of the IOP, central retinal artery occlusion, ischaemic optic atrophy. The authors emphasize the value of Doppler's diagnostic ultrasonography, a fast and non-invasive method of direct evaluation of the blood flow in the internal carotid artery system. 相似文献
63.
64.
Michelle Lucinda DeOliveira M.D. Tarcisio Triviño M.D. Ph.D. Gaspar de Jesus Lopes Filho M.D. Ph.D. 《Journal of gastrointestinal surgery》2006,10(8):1140-1143
Carcinoma of the papilla of Vater is classified as periampullary cancer representing 5% of all gastrointestinal tract malignancies.
Early and accurate diagnosis is important for those patients with a tumor of the papilla, as the prognosis is more favorable
than in other periampullary neoplasms. Endoscopically obtained biopsies from suspicious papillae can detect an early tumor,
although even for skilled pathologists it is often difficult to differentiate carcinomas from noninvasive lesions on the basis
of forceps biopsies. The purpose of this study was to assess the preoperative diagnostic accuracy of duodenoscopy appearance
and biopsy in all cases with suspicion of tumor. Thirty patients with suspicion of carcinoma of the papilla of Vater and with
final diagnosis established by pancreatoduodenectomy were included in this retrospective study. In each case, a comparison
was made between endoscopic biopsy and duodenoscopic appearance. Duodenoscopic appearance sensitivity and accuracy for malignancy
were 86% and 83%, respectively, whereas endoscopic biopsy sensitivity and accuracy were 65% and 67%, respectively. Although
preoperative diagnosis of carcinoma of the papilla of Vater is useful for making therapeutic decisions, the diagnostic value
of the endoscopic appearance was superior to endoscopic biopsy in this series.
Presented at the 2003 American Hepato-Pancreato-Biliary Association Congress, Miami, Florida, February 27-March 3, 2003.
Supported by FADA-CAPES/PROP 200J (M.L.D.). 相似文献
65.
José A Pe?agarícano Nikos Papanikolaou Yulong Yan Emad Youssef Vaneerat Ratanatharathorn 《Radiotherapy and oncology》2005,76(1):72-78
BACKGROUND AND PURPOSE: Helical tomotherapy can eliminate the need for junction lines. The goal of this study is to evaluate tomotherapy in the delivery of CSA radiation and measurement of plan quality using physical parameters in comparing conventional (CSA-RT) and helical tomotherapy (CSA-TOMO) plans. PATIENTS AND METHODS: CSA-TOMO and CSA-RT plans were created for dosimetric comparison. Integral dose values were calculated. The ratios D50% (dose received by 50% of the organ at risk's volume) and D10% (dose received by 10% of the organ at risk's volume) were calculated representing large volumes and small volumes of organs at risk receiving significant dose. RESULTS: When considering D50% and D10%, CSA-TOMO has a dosimetric advantage over CSA-RT for most organs at risk. The body integral dose was higher for the CSA-TOMO plan by approximately 6.5%. CONCLUSIONS: Tomotherapy is a feasible alternative for treatment of CSA. Analysis shows that tomotherapy improves dose ratios over conventional radiation for most organs at risk. The impact of a small increase in whole body integral dose is unknown. Long-term follow-up will be needed to answer this question as others have argued of the possibility of increased risk of secondary malignancies due to delivery of radiotherapy with IMRT. 相似文献
66.
Balloon occlusion of the internal carotid artery in 40 cases of giant intracavernous aneurysm: technical aspects,cerebral monitoring,and results 总被引:13,自引:2,他引:11
V. Vazquez Añon A. Aymard Y. P. Gobin A. Casasco D. Rüffenacht M. H. Khayata E. Abizanda A. Redondo J. J. Merland 《Neuroradiology》1992,34(3):245-251
Summary We have studied the results of carotid occlusion in the treatment of giant intracavernous carotid artery (ICA) aneurysms in 40 patients. Clinical, angiographic, Doppler and cerebral blood flow (CBF) criteria for tolerance of occlusion are discussed. The patients had headaches (47.5%), cranial nerve compression (87.5%), decreased visual acuity (20%), ruptured aneurysm (15%) and 5% were asymptomatic. Balloon occlusion tests were performed under light sedation anaesthesia: a successful test required perfect clinical tolerance and adequate angiographic collateral circulation in arterial, parenchymatous, and venous phases. Additional criteria include xenon 133 CBF measurements, and transcranial Doppler sonography of the middle cerebral artery. According to these criteria, 5 patients did not tolerate test occlusion and required an extra-intracranial (EC-IC) bypass. Mean follow-up was 4.7 years. All patients were radiologically cured of their ancurysm, and in 35 the symptoms resolved, although 3 had persistent ocular motor nerve palsies, and in 4 visual defects were unchanged. Complications were 1 permanent and 3 transient neurological deficits. Balloon occlusion of the ICA is an effective, reliable form of treatment for intracavernous giant aneurysm and should replace surgical ligation of the cervical carotid artery. With CBF or Doppler monitoring, the risk of neurological deficit is diminished. EC-IC bypass prior to ICA occlusion is indicated if test occlusion is not tolerated. 相似文献
67.
68.
M I Arranz Pe?a E Saenz Lope 《Zeitschrift für klinische Chemie und klinische Biochemie》1988,26(11):791-793
A nitrogen-specific gas-chromatographic method is described for the quantitative analysis of soluphylline without the need for derivatization or evaporation of solvent, and using only 50 microliters of serum. The analysis is performed isothermally on a silicone stationary phase, 2% SP 2250 DA (Supelco). After a single neutral extraction with ethyl acetate containing the internal standard (beta-hydroxypropyl theophylline), an aliquot of the organic solvent is injected directly into the gas chromatograph. The detector sensitivity (least measurable amount) for soluphylline was 1 ng. 相似文献
69.
F. J. Barbado J. J. Vázquez J. M. Pe?a F. Arnalich J. Ortiz-Vázquez 《Postgraduate medical journal》1992,68(805):884-887
Comparison was made of the aetiology and methods of diagnosis in two series of patients meeting the classic criteria of pyrexia of unknown origin during 1968-1981 and during 1982-1989 seen in the Department of Internal Medicine at La Paz University Hospital, Madrid, Spain. There was a statistically significant decrease in the percentage of infections and an increase in neoplasms and connective tissue disorders in the second series. The percentage of patients diagnosed by laparatomy was similar in both series but the diagnosis yield at laparotomy was greater in the second period. Pyrexia of unknown origin continues to be a condition which can defy clinical expertise in in spite of advances in diagnostic techniques. 相似文献
70.
J. Sanchez Burson J. Graña Gil M. Rosales Rodriguez A. Atanes Sandoval C. Alonso Blanco F. Galdo Fernandez 《Clinical rheumatology》1992,11(2):261-264
Summary We have studied the characteristics of arthritis present in 32 patients with Behçet's disease (BD), and how this arthritis is related to the HLA markers class I. 84% of the patients presented arthritis, the most common being monoarthritis as the initial presentation, and oligoarthritis in subsequent episodes. In 63% of the cases, the development was in episodes of acute/subacute arthritis. We found statistically significant association between antigens B-5 and B-51, and the group with BD, with a relative risk of 3.89 and 4.71 respectively. The attempt to relate markers B-5, B-51 and B-27 to the presence of arthritis as well as to its manifestation and further development was not conclusive. 相似文献