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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   
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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   
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OBJECTIVE: to determine the effect of dance-based aerobic exercise on indices of falling in older women. DESIGN: an exercise intervention trial with participants assigned either to an exercise group or to a control group. SETTING: an exercise hall at a community centre for senior citizens. PARTICIPANTS: thirty-eight healthy women aged 72-87 years, living independently in the community. INTERVENTION: twenty women performed dance-based aerobic exercise for 60 minutes, 3 days a week, for 12 weeks. The exercise included single-leg standing, squatting, marching, and heel touching; and targeted balance, strength, locomotion/agility, and motor processing. MAIN OUTCOME MEASURES: single-leg balance with eyes open/closed and functional reach as balance, hand-grip strength and keeping a half-squat position as strength, walking time around two cones and 3-minute walking distance as locomotion/agility, and hand-reaction time and foot tapping as motor processing. RESULTS: at the pre-test, both exercise and control groups performed similarly in all tests. At the end of the intervention, the exercise group showed significantly greater single-leg balance with eyes closed, functional reach, and walking time around two cones. In contrast, there were no significant improvements in any of the test measures in the control group. CONCLUSIONS: dance-based aerobic exercise specifically designed for older women may improve selected components of balance and locomotion/agility, thereby attenuating risks of falling.  相似文献   
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