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71.
Recent studies have shown that vasodilator-induced ischemic electrocardiographic (ECG) changes have incremental prognostic value over normal SPECT myocardial perfusion imaging (MPI) and identify patients at higher risk for cardiac events. The prognostic value of vasodilator-induced ischemic ECG changes in the setting of normal PET MPI has yet to be determined. We sought to determine the prognostic importance of dipyridamole-induced ischemic ECG changes in patients with normal 82Rb PET myocardial perfusion images. METHODS: Between 2000 and 2003, 2,029 consecutive patients undergoing dipyridamole stress 82Rb PET at the University of Ottawa Heart Institute were evaluated. Patients with normal PET MPI and interpretable ECGs were enrolled. Electrocardiograms were assessed for ST depression or elevation and patients were categorized into those with and without dipyridamole-induced ischemic ECG changes. Images were graded using the 17-segment model. Follow-up information was obtained by telephone interview, from hospital records, or from treating physicians. All cardiac events (cardiac death, nonfatal myocardial infarction [MI], percutaneous coronary intervention, coronary artery bypass grafting, or angiography) were verified with hospital records. RESULTS: Of the 629 enrolled patients with normal PET MPI, 72 patients had dipyridamole-induced ischemic ECG changes. There was no significant difference between the 2 groups in the combined endpoint (cardiac death, nonfatal MI, and revascularization) at follow-up (mean +/- SD, 27.1 +/- 13 mo). There were no cardiac deaths in either group. One (1.4%) patient with ischemic ECG changes had a nonfatal MI (0.6% annual event rate). Two (2.8%) patients with ischemic ECG changes required revascularization compared with 11 (2.0%) in the nonischemic ECG group. CONCLUSION: Normal 82Rb PET confers an excellent prognosis regardless of dipyridamole-induced ST depression.  相似文献   
72.
BACKGROUND: We examined whether pulse wave velocity (PWV), determined by brachial ankle arterial pressure wave measurements, using a newly developed, fully automated device could be a surrogate measure for carotid femoral PWV. METHODS & RESULTS: This device (AT-form PWV/ABI, Nippon Colin, Komaki, Japan) can simultaneously monitor bilateral brachial and ankle pressure wave forms using the volume plethysmographic method, with two optional tonometry sensors for carotid and femoral arterial wave measurements. We examined the right brachial-right ankle PWV and left carotid-left femoral PWV in 89 normotensive and untreated hypertensive patients. The brachial ankle PWV correlated well with carotid femoral PWV (r = 0.755, P <.00001). The Bland-Altman plots of the two variables, however, showed a significant difference exists between the two techniques over the range of measurement. The within-observer and between-observer coefficients of variation of the brachial ankle PWV were 6.5% +/- 4.1% and 3.6% +/- 3.9%, respectively. To determine the factors affecting brachial ankle PWV, we studied treated and untreated hypertensive patients with World Health Organization stage I (n = 146), stage II (n = 74), or stage III (n = 54). In multiple regression analysis, age, brachial ankle PWV, and the presence of diabetes were significant predictors of the severity of hypertensive organ damage. Age, systolic blood pressure, and the stage of hypertensive organ damage were major determinants of brachial ankle PWV. CONCLUSIONS: Although the brachial ankle PWV does not agree with the carotid femoral PWV, this parameter may yet become a new, useful measure for arterial stiffness. Further longitudinal studies are necessary to confirm the clinical significance of the brachial ankle PWV.  相似文献   
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An 80-year-old man was under annual surveillance esophagogastroduodenoscopy after endoscopic submucosal dissection(ESD) for early gastric cancer(EGC).Two years after the initial ESD, a 0-Ⅱc type metachronous EGC lesion, 8 mm in size, without an ulcer scar, was found in the gastric antrum.The estimated tumor depth was up to the mucosa, and biopsy revealed well and poorly differentiated adenocarcinoma.ESD was performed for this lesion and en bloc resection with negative margins was achieved.Histopathological examination revealed an adenosquamous carcinoma 8 mm in size invading the deep submucosal layer(1600 μm), with lymphovascular invasion, consistent with the diagnosis of non-curative resection.Additional gastrectomy was recommended for this patient; however, two months after the ESD, preoperative computed tomography revealed multiple liver metastases, and the patient was considered as an unsuitable candidate for surgical resection.Systemic chemotherapy was therefore started; however, the patient died of gastric cancer 27 mo after the second ESD.Early gastric adenosquamous carcinoma localized to the mucosa and submucosa is extremely rare and its clinical behavior is not well known.The present report is very significant in that it underscores the distinct possibility of gastric adenosquamous carcinoma being very aggressive and fatal even when detected at an early cancer.  相似文献   
75.
Autologous stem cell transplantation (ASCT) is a treatment option for HIV-positive patients with non-Hodgkin lymphoma (NHL) and multiple myeloma (MM). However, the prognosis after ASCT in HIV-positive Japanese patients remains unclear. The aim of this study was to evaluate the impact of HIV infection on transplant outcomes after ASCT in Japan. Using the national database of the Japan Society for Hematopoietic Cell Transplantation, we retrospectively evaluated patients with NHL (n?=?3862) and MM (n?=?2670) who underwent their first ASCT between 2001 and 2014. The presence of HIV antibody was used to diagnose HIV infection. Fifty-six patients with NHL (1.4%) and 23 with MM (.8%) were positive for HIV antibody. Among patients with NHL overall survival (OS) was lower in HIV-positive patients than in HIV-negative patients (5-year OS: HIV-positive patients, 44% versus HIV-negative patients, 65%; P?<?.001). In a multivariate analysis HIV infection was significantly associated with an increased risk of overall mortality (hazard ratio, 2.30; P?<?.001). The incidence of relapse was higher in HIV-positive patients (P?=?.036), whereas there was a similar incidence of nonrelapse mortality (P?=?.879). OS in patients with MM was similar between those with/without HIV infection (5-year OS: HIV-positive patients, 61% versus HIV-negative patients, 63%; P?=?.988). HIV infection was associated with a higher risk of overall mortality and relapse after ASCT for NHL in a Japanese population.  相似文献   
76.
Volumetric detection and accurate quantification of fluorescent proteins in entire animals would greatly enhance our ability to monitor biological processes in vivo. Here we present a quantitative tomographic technique for visualization of superficial and deep-seated (>2-3 mm) fluorescent protein activity in vivo. We demonstrate noninvasive imaging of lung tumor progression in a murine model, as well as imaging of gene delivery using a herpes virus vector. This technology can significantly improve imaging capacity over the current state of the art and should find wide in vivo imaging applications in drug discovery, immunology, and cancer research.  相似文献   
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OBJECTIVES: To investigate the disruption of neural circuits in the frontal lobes and limbic structures in late-life depressed patients compared with healthy controls, and to examine the correlation between the degree of microstructural abnormalities of white matter and clinical symptom severity in late-life depression. METHODS: Thirteen patients with late-life depression and matched control subjects underwent diffusion tensor imaging. Fractional anisotropy (FA), an index of the integrity of white matter tracts, was determined in the white matter of frontal, temporal, and occipital brain regions and the corpus callosum. RESULTS: A significant reduction was found in white matter FA values of widespread regions of the frontal and temporal lobes of depressed patients. Also, there was some evidence suggesting that white matter FA values of the inferior frontal brain region are inversely related to severity of depression. CONCLUSIONS: These results suggest the possible loss of integrity within frontal and temporal white matter fibre tracts and implicate the orbitofrontal circuit in symptom severity in late-life depression.  相似文献   
80.
Iodine-131 metaiodobenzylguanidine (131I-MIBG) therapy is an effective treatment for patients with malignant paraganglioma for which surgical resection is not indicated. We performed high-dose 131I-MIBG therapy on two patients with malignant paraganglioma and multiple bone metastases. The bone metastases were diagnosed by magnetic resonance imaging (MRI). Metastatic bone lesions were evaluated by whole-body 131I-MIBG imaging and bone scintigraphy. Whole-body 131I-MIBG imaging showed extensive metastatic bone lesions, whereas conventional bone scintigraphy did not. There was a remarkable discrepancy between 131I-MIBG imaging and bone scintigraphy in the diagnosis of metastatic bone lesions of malignant paraganglioma in our two patients. High-dose 131I-MIBG imaging may detect early stages of bone metastases, compared with bone scintigraphy, in patients with malignant paraganglioma.  相似文献   
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