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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  

While risk factors of osteoporosis in Western populations have been extensively documented, such a profile has not been well studied in Caucasians of non-European origin. This study was designed to estimate the modifiable distribution and determinants of bone mineral density (BMD) among Iranian women in Australia.  相似文献   
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When (not) to stop a clinical trial for benefit   总被引:4,自引:0,他引:4  
Pocock SJ 《JAMA》2005,294(17):2228-2230
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A P Kirk  S Jain  S Pocock  H C Thomas    S Sherlock 《Gut》1980,21(1):78-83
A long-term follow-up of at least 10 years or until death of 44 patients taking part in a controlled prospective trial of prednisolone therapy in hepatitis B antigen negative chronic active hepatitis (lupoid hepatitis) has been performed at the Royal Free Hospital, London. Patients presenting between 1963 and 1967 were randomly allocated into control and treatment groups. Ten year life table survival curves showed a significantly improved survival in the treatment group where 63% of patients were alive at 10 years compared with only 27% in the control group (log rank test, P = 0.03). The median survival in the treatment group was 12.2 years compared with 3.3 years in the control group. The mean duration of treatment was 4.5 years. Age, presence of antinuclear factor, cirrhosis, or level of serum transaminases at presentation did not appear to affect survival. Male patients if untreated had a poorer prognosis than females (P = 0.02). The natural history of chronic active hepatitis appeared from clinical, biochemical, and histological findings to be from an active hepatitis or cirrhosis to inactive macronodular cirrhosis. Prednisolone therapy significantly improved survival by reducing mortality in the early active phase of the disease.  相似文献   
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The auscultatory signs in 90 subjects with hypertrophic obstructive cardiomyopathy are described. The late-onset ejection systolic murmur and its responses to vaso-active manoeuvres reflect a volume-dependent outflow tract obstruction. Late vibrations of the systolic murmur, not uncommonly recorded at the apex, are due to associated mitral incompetence. Non-ejection systolic clicks may occur, and the likely explanation is inequality of the functional length of the mitral chordae tendineae secondary to asymmetrical myocardial hypertrophy. The second heart sound is often abnormal, usually with delay in the aortic component. Some correlation was demonstrated between the relative degrees of left and right ventricular outflow obstruction and the pattern of splitting of the second heart sound. Reversed or partially reversed splitting is usually associated with a more severe left ventricular outflow obstruction. Ejection systolic clicks and early diastolic murmurs occur infrequently, but are not incompatible with the diagnosis of hypertrophic obstructive cardiomyopathy.  相似文献   
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GOALS: To assess the incidence of oral complementary and alternative medicine (CAM) usage by gastroenterology patients at a single university center and compare against controls. BACKGROUND: The public awareness and usage of CAM have increased. The use of CAM has been described in patients with functional bowel disorders; however, their role in patients with gastrointestinal disease is less clear. STUDY: Patients attending luminal gastroenterology clinics and customers at local supermarkets completed a 30-point, structured questionnaire assessing their use of CAM. RESULTS: A total of 1,409 subjects were recruited. The incidence of CAM use was 49.5% for inflammatory bowel disease, 50.9% for irritable bowel syndrome, 20% for general gastrointestinal diseases, and 27% for controls. Pearson's chi(2) tests showed that patients with inflammatory bowel disease (IBD) or irritable bowel syndrome were more likely to use CAM than controls (P < 0.001). Binary logistic regression analysis showed that females were more likely to take CAM than men (P < 0.05). CONCLUSIONS: The percentage of CAM users among patients with IBD is similar to those with a functional diagnosis. Increasing numbers of IBD patients are using CAM in addition to conventional therapy. Awareness of this may prevent adverse CAM and conventional drug interactions.  相似文献   
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