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131.
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
132.
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
133.
Baća I Perko Z Bokan I Mimica Z Petricević A Druzijanić N Situm M 《Surgical endoscopy》2005,19(5):650-655
Background The role of laparoscopic colon resection in the management of colon cancer is still controversial. In this article, the surgical strategy and techniques are described, with further consideration of the oncologically relevant aspects.Methods Between March 1993 and July 2003, we performed laparoscopic right hemicolectomy in 56 patients with right colon carcinoma. Average age was 74.5 years (range, 17–92). We performed a standardized surgical procedure that included mobilization from the vascularized mesenteric bridges with a window technique, transection of the ileocolic lymphovascular pedicle, and lateral and proximal mobilization of the ileocecum, ascending colon, right flexure, and proximale transversum. After enlargement of one of the trocar incisions the exteriorized colon was resected and an extracorporeal anastomosis was performed in the standard manner.Results There were no conversions to open. The mean operating time was 119 ± 38 min, the mean length of resected colon was 27.8 ± 4.48 cm, and the average width of the clear margins was 6.8 ± 5.3 cm. One patient died. Lymph nodes were positive in 21 patients. The 5-year survival rate in the 48 patients who were operated on with curative intent was 75%. We have had two local recurrences. The overall 5-year mortality-free fraction was 63%. Cox multivariate analysis showed that the mortality-prognostic factors were tumor stage and length of resected colon, whereas Kaplan-Meier analysis showed that the mortality-prognostic factors were positive lymph nodes and tumor stage.Conclusions Our results show that laparoscopic right hemicolectomy for colon cancer can be performed safely. Complications and recurrence rates are comparable to those for left-sided laparoscopic and open procedures. Therefore, we recommend this procedure as the method of choice. Laparoscopically treated patients with stage II and stage III disease have almost the same cumulative rate of survival. 相似文献
134.
Herpetic esophagitis 总被引:1,自引:0,他引:1
135.
136.
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
137.
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
138.
OBJECTIVE:
Inflammation plays an important role in the development of chronic lung disease (CLD), which has become a major cause of morbidity in surviving infants less than 1250 g at birth. The authors hypothesized that the progression of this inflammation and, therefore, the establishment of CLD would be decreased with the use of early prophylactic inhaled corticosteroids. Short, and long term respiratory and neurodevelopmental outcomes were also examined.DESIGN:
A double-blind, randomized placebo controlled trial.SETTING:
Level-III neonatal intensive care unit.POPULATION STUDIED:
Sixty infants less than 1250 g at birth, diagnosed with respiratory distress syndrome and requiring ventilatory support at 72 h of age were enrolled in the study.INTERVENTION:
Infants enrolled received either placebo or beclomethasone diproprionate by a metered dose inhaler, which was used in-line with the ventilator circuit while the infant was ventilated and then via a spacer until 28 days of age.RESULTS:
Thirty infants were given beclomethasone and 30 were given placebo. There were two deaths in each group. Among the surviving infants, the frequency of moderate-to-severe CLD was 17% in each study group. Mean time to extubation was not different for beclomethasone compared with placebo at 16.4 and 12.5 days (P=0.12), respectively. The requirement for intravenous corticosteroids was lower in the beclomethasone-treated group (RR 0.67, 95% CI 0.43 to 1.04), although this difference was not statistically significant. The incidence of growth failure, infection and intraventricular hemmorhage did not differ between the two groups. Long term outcomes were not different with respect to the incidence of respiratory re-admissions, cerebral palsy, developmental delay, blindness or deafness.CONCLUSIONS:
Early treatment with inhaled beclomethasone diproprionate did not reduce the incidence of CLD or decrease the duration of mechanical ventilation. The decrease in intravenous corticosteroid use was not statistically significant. Long term outcome was not affected. 相似文献139.
The breast is a complex anatomical structure where achieving a homogeneous dose distribution with radiation treatment is difficult. Despite obvious similarities in the approach to such treatment (using tangents) there is variation in the process of simulation, planning and treatment between radiation oncologists. Previous Australasian studies in the treatment of lung cancer, prostate cancer and Hodgkin’s disease highlighted considerable variation in many areas of treatment. As part of a multicentre breast phantom study involving 10 radiation oncology departments throughout New South Wales (NSW) and the Australian Capital Territory (ACT), a 22-question survey was distributed. The aim of the survey was to assess the extent of variation in the approach to the simulation, planning and treatment of early breast cancer using tangents. Responses from 10 different radiation oncology departments revealed variation in most areas of the survey. There is no reason to assume similar variations do not occur Australasia wide. Studies involving overseas radiation oncologists also reveal a wide variation in treating early breast cancer. The consequences of such variations remain unclear. 相似文献
140.
A patient with progressive osteolysis of the carpal and tarsal bones with glomerulonephritis of unusual severity is described. There was a notable absence of osteodystrophy in this and other reported cases who had chronic renal failure. 相似文献