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排序方式: 共有1731条查询结果,搜索用时 15 毫秒
131.
Sickle cell disease: imaging of cerebrovascular complications 总被引:3,自引:0,他引:3
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134.
Regional myocardial dysfunction: evaluation of patients with prior myocardial infarction with fast CT 总被引:1,自引:0,他引:1
Lipton MJ; Farmer DW; Killebrew EJ; Bouchard A; Dean PB; Ringertz HG; Higgins CB 《Radiology》1985,157(3):735-740
A prototype ultrafast cine computed tomographic (CT) scanner, designed specifically for cardiac imaging, was used to evaluate a preliminary series of patients with prior myocardial infarction (n = 21) and a control group without coronary artery disease (n = 5). Multilevel 50-msec CT scan exposures were obtained during peripheral intravenous bolus injections of contrast medium. A comparison was made between cine-CT scans and standard left ventriculographic images in assessing segmental left ventricular motion. Results indicate that cine CT, performed at sufficiently rapid speeds (20 scans per second) to allow useful analysis of regional ventricular wall motion, can provide adequate image quality. Analysis of 110 segments revealed a good correlation (90.9%) between the two techniques in characterizing normal from abnormal regional wall motion. Cine CT, based on this initial study, demonstrates considerable potential for evaluating not only cardiac chamber dimensions but also segmental wall dynamics. 相似文献
135.
A new needle-wire system has been developed for localization of nonpalpable breast lesions. The curved-end wire, which is made of a tough pseudoelastic alloy, eliminates many of the pitfalls of this procedure for both the radiologist and the surgeon. Advantages of this new system include the ability to anchor the needle during filming, the ability to easily reposition the needle if necessary, the option of injecting dye, the inability to transect the wire during surgery, and the option of leaving both the needle and wire in place in the subject to allow easier dissection during biopsy. 相似文献
136.
Woodrum DT Ford JW Ailawadi G Pearce CG Sinha I Eagleton MJ Henke PK Stanley JC Upchurch GR 《Journal of the American College of Surgeons》2005,201(3):398-404
BACKGROUND: A predilection exists for men to develop abdominal aortic aneurysms (AAAs), but the reasons for this gender predisposition are not known. Matrix metalloproteinase-9 (MMP-9) has been implicated in both human and experimental AAAs. This investigation tested the hypothesis that male and female gender differences exist in the production of MMP-9 by rat aortic smooth muscle cells (RASMCs). STUDY DESIGN: In the first set of experiments, cultured male and female RASMCs were stimulated with interleukin-1 beta (IL-1beta) at 2 ng/mL. Messenger RNA was extracted from the RASMCs and gene expression of MMP-9 and tissue inhibitor of metalloproteinase-1 (TIMP-1), an MMP-9 inhibitor, was measured by quantitative real-time polymerase chain reaction. Cell culture media were collected for measurement of MMP-9 protein levels and MMP-9 activity by Western blotting and gelatin zymography, respectively. In the second set of experiments, male RASMCs were treated with 17-beta-estradiol (10(-10) to 10(-6) mol/L) and MMP-9 activity was measured. In the third set of experiments, male rats were pretreated with estradiol, and MMP-9 activity was measured in the media from explanted aortas. RESULTS: MMP-9 gene expression was 10-fold higher in male versus female RASMCs (p=0.003). MMP-9 protein levels (p=0.005) and gelatinolytic activities (p=0.01) were also greater in male than female RASMCs. TIMP-1 expression was fourfold higher in male versus female RASMCs (p<0.001). Estradiol-treated male RASMCs did not exhibit a decrease in MMP-9 activity. But aortic explants from male rats pretreated with 17-beta-estradiol had 60% less MMP-9 activity than explants from male controls (p=0.03). CONCLUSIONS: MMP-9 and TIMP-1 are greater in male than in female RASMCs. These findings support the tenet that gender-related differences in MMP-9 may contribute to AAA formation. 相似文献
137.
Herpetic esophagitis 总被引:1,自引:0,他引:1
138.
139.
Brown AS Calachanis M Evdoridis C Hancock J Wild S Prasan A Nihoyannopoulos P Monaghan MJ 《Irish journal of medical science》2004,173(1):13-17
Background Stress echocardiography is useful for assessing patients with coronary artery disease unable to undergo formal exercise testing.
Considerable skill is required to avoid large intra- and inter-observer variability due to poor endocardial definition. Intravenous
ultrasound contrast agents are now available which may improve this variability.
Aim To study intravenous Sonovue in assessing wall motion score and ejection fraction (EF) during stress echocardiography.
Methods Thirty-eight patients undergoing arbutamine stress echocardiography for known or suspected coronary artery disease were studied.
Echocardiographic analysis of wall motion score index, endocardial border detection (EBD) and EF was performed at rest and
at peak stress before and after intravenous injection of Sonovue, by experienced and inexperienced observers.
Results All three observers noted an improvement in endocardial border definition following Sonovue (p=<0.001). At baseline, there
was a significant difference in wall motion score index between experienced and inexperienced observers at rest (p=0.01) and
at peak stress (p=0.001). Following Sonovue administration this was no longer significant (p=0.07, p=0.114). Intra-observer
variability of end diastolic, end systolic volumes (ESV) and EF improved following contrast (p<0.05) at rest and during stress.
Conclusion Sonovue significantly improved EBD and reduced intra-observer variability of EF at rest and during peak arbutamine infusion. 相似文献
140.
BACKGROUND: Through the 1990s, governments across Canada shifted health care funding allocation and organizational foci toward a community-based population health model. Major concerns of reform based on this model include ensuring equitable access to health and health care, and enhancing preventive and community-based resources for care. Reforms may act differentially relative to specific conditions and services, including those geared to chronic versus acute conditions. The present study therefore focuses on health service utilization, specifically cancer hospitalizations, in British Columbia during a decade of health system reform. METHODS: Data were drawn from the British Columbia Linked Health Data resource; income measures were derived from Statistics Canada 1996 Census public use enumeration area income files. Records with a discharge (separation) date between 1 January 1991 and 31 December 1998 were selected. All hospitalizations with ICD-9 codes 140 through 208 (except skin cancer, code 173) as principal diagnosis were included. Specific cancers analyzed include lung; colorectal; female breast; and prostate. Hospitalizations were examined in total (all separations), and as divided into first and all other hospitalizations attributed to any given individual. Annual trends in age-sex adjusted rates were analyzed by joinpoint regression; longitudinal multivariate analyses assessing association of residence and income with hospitalizations utilized generalised estimating equations. Results are evaluated in relation to cancer incidence trends, health policy reform and access to care. RESULTS: Age-sex adjusted hospitalization rates for all separations for all cancers, and lung, breast and prostate cancers, decreased significantly over the study period; colorectal cancer separations did not change significantly. Rates for first and other hospitalizations remained stationary or gradually declined over the study period. Area of residence and income were not significantly associated with first hospitalizations; effects were less consistent for all and other hospitalizations. No interactions were observed for any category of separations. CONCLUSIONS: No discontinuities were observed with respect to total hospitalizations that could be associated temporally with health policy reform; observed changes were primarily gradual. These results do not indicate whether equity was present prior to health care reform. However, findings concur with previous reports indicating no change in access to health care across income or residence consequent on health care reform. 相似文献