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991.
H. Seyer J. Honegger W. Schott M. Küchle W. J. Huk R. Fahlbusch H. Frisch 《Acta neurochirurgica》1994,131(1-2):157-159
Summary Inferior petrosal sinus sampling (IPSS) is used to evaluate the pituitary-dependency of Cushing's disease, and to predict the laterality of a microadenoma prior to transsphenoidal operation. A serious complication occured in a 14-year-old boy: he suffered brain stem ischaemia with abducens nerve palsy and hemiparesis (Raymond's syndrome). The case prompted us to reconsider the indication for this investigation. 相似文献
992.
993.
Pui-Yin Lee Wai-Hong Chen William Ng Chu-Pak Lau 《Catheterization and cardiovascular interventions》2003,60(4):558-561
Subclavian artery lesion that is associated with low complication rate could be treated by percutaneous intervention effectively. However, the success of endovascular therapy for occlusive lesion may be limited by failure to cross with a guidewire. We describe the use of a system using optical coherence reflectometry for navigation and radiofrequency ablation to enable wire passage through subclavian artery occlusion that could not be crossed by conventional guidewires. 相似文献
994.
同步记录72例拟诊冠心病患者头胸导联(HC)及常规导联(wilson)心电图(ECG),并与冠脉造影结果对照。结果:HC与Wilson导联ECG对冠心病诊断的敏感性分别为88.9%与81.5%,特异性33.3%与27.8%,准确性75%与68.1%;二组导联对比无明显差异(P>0.05);对右心室梗塞、缺血及左心室后壁缺血.HC导联的敏感性(91.7%)及准确性(94.4%)均显著高于Wilson导联(12.5%、70.8%,P<0.01),并与冠状动脉病变程度呈高度正相关。HC导联优于Wilson导联。 相似文献
995.
996.
Plasma volume estimation using indocyanine green with biexponential regression analysis of the decay curves 总被引:2,自引:0,他引:2
We studied seven analytical methods of estimating the plasma volume from the decay curves of indocyanine green. Fifteen volunteers received 1.0 mgkg−1 of the dye by intravenous injection and the plasma concentration was measured continuously using spectrophotometry. Plasma volumes were calculated using three single-regression methods (1-a, 1-b, 1-c) and four biexponential regression methods (2-a, 2-b, 2-c, 2-d). The means (SD) of 1-a, 1-b and 1-c were 39 (5.0), 44 (5.7) and 54 (11.5) mlkg−1 , respectively, and these were significantly different from each other (p < 0.05). The values for methods 2-b, 2-c and 2-d were similar to each other: 39 (4.6), 40 (4.1) and 40 (4.0) mlkg−1 , respectively. These required more than 3 min circulation or mixing time. When the time allowed for mixing was less than 3 min (method 2-a) the plasma volume was underestimated. We conclude that plasma volume estimation using indocyanine green and spectrophotometry is most accurate when the mixing time is adequate (3–5 min) and the decay curves are analysed using biexponential regression. 相似文献
997.
998.
Gianmauro Sacchetti Eugenio Inglese Angelo S Bongo Franco Aina Marco Brambilla Alberto Baroli Carmelo Cernigliaro Pierfranco Dellavesa Edgardo Pittaluga Marco Rudoni 《European journal of nuclear medicine and molecular imaging》1997,24(10):1230-1236
The aim of this study was to determine the diagnostic accuracy of technetium-99m tetrofosmin myocardial imaging for the localization
of coronary artery stenoses of different degrees of severity. Stress-rest single-photon emission tomography (SPET) was performed
on separate days in 80 patients (64 males, 16 females; mean age 61 years; 43 patients with previous myocardial infarction;
18 patients with pharmacological stress), within 6 months of coronary angiography. Scintigraphic images were blindly and independently
evaluated by three observers. Coronary stenosis was defined as a >50% narrowing in luminal diameter; severe stenosis was defined
as a proximal stenosis of >75% or a peripheral stenosis of >90%. Coronary angiography revealed normal coronary arteries or
insignificant coronary stenosis in 13 patients and significant coronary stenoses in 67 patients. The sensitivity and specificity
of 99mTc-tetrofosmin SPET in respect of severely stenosed vessels were, respectively, 80% and 65% for the left anterior descending
artery (LAD), 100% and 46% for the right coronary artery (RCA) and 58 and 78% for the left circumflex artery (LCx) territories.
Considering all the significantly stenosed vessels, a significant decrease in sensitivity was observed for LAD territories
(to 59%, P=0.05), and a nonsignificant decrease for RCA (88%) and LCx (47%) territories while specificity values remained essentially
unchanged. No significant changes in sensitivity or specificity were observed when regions with previous myocardial infarction
were excluded. In conclusion, the sensitivity of 99mTc-tetrofosmin SPET for the localization of individual stenosed vessels is only moderate when all significant stenoses are
considered, but the ability of this technique to predict the location of severe coronary artery stenoses seems satisfactory,
with the exception of the low specificity in respect of RCA territories.
Received 26 April and in revised form 7 June 1997 相似文献
999.
Kengo Yoshimitsu Hiroshi Honda Kuniyuki Kaneko Toshiro Kuroiwa Hiroyuki Irie Takashi Ueki Kazuo Chijiiwa Kenji Takenaka Kouji Masuda 《Journal of magnetic resonance imaging : JMRI》1997,7(4):696-701
Forty-nine pathologically proven gallbladder lesions were evaluated in 45 patients using dynamic MRI with a spoiled gradient pulse sequence (SPGR), to access the ability of this technique to differentiate benign from malignant gallbladder lesions. The studies were reviewed retrospectively. Signal intensity of the lesions were measured. Twenty-one malignant and 28 benign lesions were classified into three categories: polypoid, diffuse wall thickening, and exophytic. Early and delayed enhancement patterns were evaluated. For the polypoid masses, malignant lesions (n = 9) demonstrated early and prolonged enhancements, whereas benign lesions (n = 14) had early enhancement with subsequent washout (P < .05). For diffuse gallbladder wall thickening, malignant lesions (n = 6) demonstrated early and prolonged enhancement and benign lesions (n = 14) showed relatively slow, prolonged enhancement (P < .05). The exophytic masses (n = 6) all were malignant and demonstrated early and prolonged enhancement. Dynamic MRI can help differentiate benign from malignant gallbladder lesions. 相似文献
1000.
T. KRANTZ F. SZTUK F. SWIATEK J. JACOBSEN N. H. SECHER 《Acta anaesthesiologica Scandinavica》1997,41(6):719-724
Background: We evaluated the ability of the standards issued by the Danish Society of Anaesthesiologists to reflect a blood loss.
Methods: In 9 pigs bled (0–24 ml kg-1 ) and retransfused (to 28 ml kg-1 ) during halothane anaesthesia, central cardiovascular, thoracic electrical impedance (TI), oxygen, acid-base and temperature variables were recorded.
Results: With the recommendation for minor surgery (mean arterial pressure (MAP) and heart rate (HR)), the correlation to the blood loss was 0.74 ( P < 0.001) and with that for major surgery (MAP, HR, central venous pressure (CVP) and rectal temperature (Tempr )) it was 0.79 ( P < 0.001). With the recommendation for extensive surgery (MAP, HR, CVP, pulmonary artery catheter variables and the central-peripheral temperature difference (ΔTempr-t )), the correlation was 0.84 ( P < 0.001). Non-invasive monitoring (MAP, HR, ΔTempr-t TI and near-infrared spectroscopy of the brain (Sinvos O2 )) was only slightly better than basal monitoring (r=0.76, P < 0.001). However, adding arterial base excess (BE), TI and peripheral temperature (Tempt ) to the recommendation for major surgery resulted in a correlation of 0.87 ( P < 0.001), while adding BE and TI to the recommendation for extensive surgery raised correlation to only 0.88 ( P < 0.001).
Conclusion: When the recommendations were followed the correlation to the blood loss ranged from 0.74–0.84. However, with the recording of MAP, HR, CVP, ΔTempr-t, BE and TI a correlation of 0.87 was achieved, indicating that a pulmonary artery catheter may not be in need for patients undergoing surgical procedures with expected haemorrhage. 相似文献
Methods: In 9 pigs bled (0–24 ml kg
Results: With the recommendation for minor surgery (mean arterial pressure (MAP) and heart rate (HR)), the correlation to the blood loss was 0.74 ( P < 0.001) and with that for major surgery (MAP, HR, central venous pressure (CVP) and rectal temperature (Temp
Conclusion: When the recommendations were followed the correlation to the blood loss ranged from 0.74–0.84. However, with the recording of MAP, HR, CVP, ΔTemp