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31.
Transmission computed tomography (TCT) data provides useful complementary information to single-photon emission computed tomography (SPECT) reconstructions, especially for cardiac studies. In particular, TCT data has been used to correct for nonuniform attenuation in the chest. Typically the transmission data are acquired in a separate acquisition, but simultaneous acquisition is preferable both to save time and to avoid difficulties involved with registration. In this work, we present a technique for simultaneously acquiring 201Tl SPECT and TCT data using a 99mTc sheet source that requires only minor equipment modifications. The use of these isotopes results in cross-contamination of the emission and transmission data. We present a practical technique to compensate for this contamination using post-acquisition image processing. This technique was evaluated by performing phantom and patient studies. The resulting images compare well with data obtained from separate emission and transmission studies. 相似文献
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33.
W. G. Selley FDS Hon FCST R. E. Ellis MPhil F. C. Flack PhD C. R. Bayliss MB B Chir FRCR V. R. Pearce MB FRCP 《Dysphagia》1994,9(3):162-167
Simultaneous recording of adult subjects sipping small amounts of fluid from a cup have been obtained by videofluoroscopy together with feeding respiratory patterns and swallow sounds from the Exeter Dysphagia Assessment Technique (EDAT). These allowed visual representations of respiration and swallow sounds to be superimposed on a videofluoroscopy recording using a split-screen technique. Sequentially numbered, 1/50 sec, half-frame photographic prints were examined and schematic drawings of the relevant radiographs were made. These were superimposed on to the actual EDAT printed chart of the same swallow event, theri exact time relationship with respiration and cervical swallow sounds being preserved. The results allow events in the barium videofluoroscopy to be related to events in the feeding respiratory pattern and swallow sounds recorded by EDAT. 相似文献
34.
R F Peppard W R Martin G D Carr E Grochowski M Schulzer M Guttman P L McGeer A G Phillips J K Tsui D B Calne 《Archives of neurology》1992,49(12):1262-1268
Although cognitive impairment is commonly associated with Parkinson's disease, the relative importance of cortical and subcortical pathologic changes to the development of dementia is controversial. Characteristic abnormalities in cortical glucose metabolism have been reported previously in Alzheimer's disease, a disease in which cortical changes predominate. We measured cerebral glucose metabolism with positron emission tomography in 20 control subjects and in 14 patients with PD with mental status ranging from normal to severely demented to determine whether changes in cortical glucose metabolism occur in early PD and whether the degree and pattern of metabolic change relate to the severity of dementia. The patients were divided into demented and nondemented groups according to the results of neuropsychological assessment. Age-adjusted covariance analyses were performed, since the age distribution varied between groups. The nondemented patients with PD showed widespread cortical glucose hypometabolism without any selective temporoparietal defects. The pattern of glucose hypometabolism seen in the demented patients with PD resembled that described in patients with Alzheimer's disease; ie, there was a global decrease in glucose metabolism, with more severe abnormalities observed in the temporoparietal regions. 相似文献
35.
Rectus sheath haematoma is a well‐documented but unusual cause of acute abdomen. Combination of clinical features and appropriate radiological investigations can make for a prompt diagnosis. Most authors advocate conservative management and it has been reported that patients were directly discharged from the emergency department. We report a case of rectus sheath haematoma which progressed with clinical deterioration and necessitated surgical intervention for clot evacuation. Causes, physical signs, radiological features and classification of rectus sheath haematoma are discussed. It may be necessary to continue close clinical monitoring after diagnosis of rectus sheath haematoma. 相似文献
36.
T J Tucker W C Lumma L S Payne J M Wai S J de Solms E A Giuliani P L Darke J C Heimbach J A Zugay W A Schleif 《Journal of medicinal chemistry》1992,35(14):2525-2533
A series of HIV-1 protease inhibitors containing a novel hydroxyethyl secondary amine transition state isostere has been synthesized. The compounds exhibit a strong preference for the (R) stereochemistry at the transition state hydroxyl group. Molecular modeling studies with the prototype compound 11 have provided important insights into the structural requirements for good inhibitor-active site binding interaction. N-Terminal extension of 11 into the P2-P3 region led to the discovery of 19, the most potent enzyme inhibitor in the series (IC50 = 5.4 nM). 19 was shown to have potent antiviral activity in cultured MT-4 human T-lymphoid cells. Comparison of analogs of 19 with analogs of 1 (Ro31-8959) demonstrates that considerably different structure-activity relationships exist between these two subclasses of hydroxyethylamine HIV-protease inhibitors. 相似文献
37.
Janine Barden-O'Fallon Chirayath Suchindran Amy O Tsui 《American journal of human biology》2006,18(2):214-218
This study uses data from a population-based survey to examine the fertility schedules of 704 women in a rural district of Malawi. The main objective is to assess self-reported fecundity status as a measure of fertility impairment. Life tables are used to examine the timing and tempo of births for women reporting difficulty getting pregnant as compared to women with no reported fecundity difficulties. Results of the analysis indicate that women with self-reported fecundity difficulties are older at each birth and have longer median birth intervals than do women with no reported difficulties. Cox proportional hazards models show that the report of a difficulty getting pregnant is significantly associated with at least a 30% lower likelihood of a first, second, or third birth. The relationships are not modified when accounting for demographic characteristics, previous sexual behaviors, or STI status. 相似文献
38.
Edmo Atique Gabriel Rafael Fagionato Locali Carla Cristina Romano Alberto José da Silva Duarte José Honório Palma Enio Buffolo 《European journal of cardio-thoracic surgery》2007,31(3):406-412
OBJECTIVE: The objective of this study is to evaluate the inflammatory response caused by endovascular stents in the treatment of aortic aneurysms. METHODS: Twenty-five patients underwent endovascular stent treatment from March through December 2005. The evolution of mediators (sedimentation velocity, C reactive protein, interleukin-6, interleukin-8, tumor necrosis factor-alpha, intercellular adhesion molecule-1, l-selectin), inflammatory cells (leukocytes, lymphocytes, platelets), serum creatinine and body temperature within preoperative period and in the following postoperative periods--1, 6, 24 and 48 h, 7 days, 1-3 months, was analyzed. In order to achieve statistic significance, Friedman test and Wilcoxon test were used, with index of significance of 5% (p<0.05). RESULTS: Peak values of sedimentation velocity, C reactive protein and interleukin-6 were observed at 7 days (p<0.0001), 48 h (p<0.0001) and 24h (p<0.0001), respectively. Tumor necrosis factor-alpha and interleukin-8 did not show statistically significant variability during the entire follow-up. In terms of intercellular adhesion molecule-1 and l-selectin, their expressive values were found in late phase of follow-up, although without statistical significance. Elevation of leukocytes count occurred in premature phase of follow-up (p<0.0001), while lymphocyte and platelet count occurred in a late phase of follow-up (p<0.0001). Serum levels of creatinine did not show significant variability during follow-up. The period between 24 and 48 h corresponded to major frequency for fever (p<0.0001). CONCLUSION: Individual mediators analysis and inflammatory cells demonstrated variability of their values during postoperative follow-up. This could help in the analysis of the inflammatory response evolution caused by endovascular stent treatment for aortic aneurysms in premature and late phases after implantation of the vascular prosthesis. 相似文献
39.
40.
Spinal extradural cavernous hemangioma 总被引:10,自引:1,他引:9
Three cases of isolated spinal extradural cavernous hemangiomas are reported, two in the thoracic and one in the lumbar region. One of them manifested as acute cord compression, the other two as chronic progressive myelopathy or radiculopathy. A total excision or subtotal excision with irradiation was performed. All of them had good functional recovery. The clinical picture, radiological diagnosis, and optimal method of treatment are discussed. The relevant literature is reviewed. 相似文献