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Templeton AW; Johnson JA; Anderson WH; Cook LT; Dwyer SJ d; Preston DF; Lee KR; Rosenthal SJ; Batnitzky S; Levine E 《Radiology》1984,151(2):527-528
The increasing use of digitally formatted imaging systems requires high-quality interactive gray-scale computer raster graphics systems for the management, display, and analog film recording of digital image and alphanumeric information. These systems are a combination of computer hardware and software and implement a set of graphics protocols. This paper describes a set of interactive graphics protocols that has been developed for clinical use. 相似文献
63.
In a patient with primary hyperparathyroidism an attempt was made to ablate a middle mediastinal parathyroid gland by forceful staining with radiographic contrast material. The gland was stained on two separate occasions, two weeks apart. Both times the serum calcium level temporarily fell to the normal range but reverted to abnormal levels. The patient ultimately required surgery for correction of hypercalcemia. The mechanism of staining and possible reasons for failure as well as potential complications are discussed. 相似文献
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Gallium-67 lung uptake: conjugate-view technique 总被引:1,自引:0,他引:1
A conjugate-view technique is derived for calculation of absolute gallium-67 (Ga-67) uptake from scintillation-camera images. The technique combines counts of posterior and anterior images of the lung with an attenuation correction obtained from cobalt-57 (Co-57) transmission imaging. The formulation is such that the effects of Compton scatter build-up are accounted for. Studies utilizing a canine model indicated that, normally, more activity is located in the chest wall than in the lungs. The quantitative technique must therefore accurately account for a variety of Ga-67 distributions, including that in the chest wall. Calculations were performed using a three-component model comparing results obtained with the conjugate-view approach to the actual uptake. These calculations suggest that an assumption of uniform activity distribution allows an accuracy of approximately +/- 10% over a broad range of body-part thicknesses and uptake by the lungs. It was concluded that the conjugate-view technique is necessarily approximate but can provide clinically useful results. 相似文献
67.
Background
Haemorrhage after Cardio Pulmonary Bypass (CPB) Surgery is a well recognised complication that leads to significant morbidity and mortality. The incidence varies between 5-25% depending upon the clinical situation. Several factors are implicated as causative but none have been precisely proved.Methods
Our study was an attempt to evaluate the haemostatic defect with particular reference to platelet function abnormalities during cardio pulmonary bypass surgery, in order to reduce the morbidity and mortality associated with post CPB haemorrhage. Flow cytometric evaluation of different platelet glycoproteins like GPIb/IX, GPIIb/IIIa and GMP-140 was done.Results
The marker expression showed deregulation during surgery which returned to base after bypass was terminated. In contrast, the cases with bleeding showed significant variation. P-Selectin (GMP 140) expression decreased progressively till 3rd post-operative day showing lack of activation of platelets in cases of severe bleeding.Conclusion
Longer duration of CPB initiates plasmin generation through heparin, which raises the PAI-1-tPA complex and thereby down regulating the functions of platelets. This suggests a link between duration of CPB, bleeding, platelet dysfunction and fibrinolysis. Hence serial estimations of the levels of GMP-140 and tPA can predict severe bleeding.Key Words: CardioPulmonary Bypass, Platelet dysfunction, flowcytometry, platelet glycoproteins, haemorrhage 相似文献68.
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葛根素对高血压患者血浆内皮素和一氧化氮的影响 总被引:29,自引:0,他引:29
目的:检测正常人与高血压病(EH)患者血浆内皮素、一气体氮的变化及葛根素对其的干预效应。方法:EH对照组口服苯磺酸氨氯地平5mg/d,或合和盐酸苯那普利10mg/d,每日一次,15d为一疗程。EH伍用治疗组同时合用5%GNS250ml+葛根素注射液400mg静滴,两组治疗前后检测血浆ET、NO水平变化。结果:EH各组血浆ET较正常人组均显著增高(P〈0.01),血浆NO水平及NO/ET比值除轻度E 相似文献