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991.
Cerebrovascular and metabolic perturbations in delayed heavy charged particle radiation injury 总被引:5,自引:0,他引:5
E H Lo K A Frankel R L Delapaz A Poljak K H Woodruff K M Brennan M H Phillips P E Valk G K Steinberg J I Fabrikant 《Brain research》1989,504(1):168-172
Focal heavy charged particle irradiation of the rabbit brain created defined lesions which were observable by nuclear magnetic resonance (NMR) and positron emission tomography (PET) imaging techniques. The lesions appeared approximately 9-11 months after left partial hemibrain irradiation with 30 Gy (230 MeV/u helium ions), and were restricted to the white matter tracts and deep perithalamic and thalamic regions. 82Rubidium PET and Gadolinium DTPA enhanced NMR imaging were used to detect blood-brain barrier perturbations. 18Fluordeoxyglucose PET studies demonstrated widespread decreases in cerebral glucose uptake in the cortex and thalamus of the irradiated hemisphere. NMR and PET imaging results correlated well with histological findings. Rabbits irradiated with 15 Gy did not demonstrate any abnormalities in the brain with sequential NMR scans through 14 months post-irradiation. 相似文献
992.
S Maggi G M Giuseppetti G Spiga M Macchini G Procaccini S Gregori F Amici 《La Radiologia medica》1989,78(1-2):101-106
The last generation of mammographic equipment allows mammography to be performed with direct magnification techniques, thanks to such technical features as microfocus, high focus-film distance, high-power generators. The authors compared the diagnostic yield of two different equipment sets, with 1.4x and 2x magnification respectively, and verified the utility of magnification radiography. A significant reduction was obtained in questionable diagnoses (42 to 18) in a group of 63 patients, with no evidence of substantial differences in the diagnostic yield of the images obtained with different magnification ratios. An objective analysis of the system resolution power privileges 2x magnification ratio, which however implies an increase in the average dose to the breast. The use of faster recording systems reduces the dose by 50%, though maintaining good image quality. 相似文献
993.
994.
M T Hegel G G Abel M Etscheidt S Cohen-Cole C I Wilmer 《Journal of behavior therapy and experimental psychiatry》1989,20(1):31-39
The hyperventilation syndrome is present in as many as 50% of patients with non-cardiac chest pain. This study evaluated a behavioral treatment of this disorder in three adult females. They had long histories of chest pain and were documented to be free of coronary artery disease. Each subject met the DSM-III-R diagnostic criteria for an anxiety disorder. Following treatment, all subjects showed a marked decrease in the frequency and intensity of chest pain episodes and in the frequency of shortness of breath episodes. Two subjects maintained their progress at one-year follow-up. The results lend support to the efficacy of controlled breathing and relaxation training for the treatment of hyperventilation-related chest pain and to the inclusion of a hyperventilation provocation test in the diagnosis of the syndrome as well as its role in changing cognitions regarding cardiac status. Also discussed is the rationale for treating hyperventilation related chest pain in a medical care setting. 相似文献
995.
Sixty chronic alcoholic patients, aged 35.6 +/- 0.7 years and an average alcoholic history of 9.3 +/- 0.5 years were examined. Atrial fibrillation was detected at 24 h ECG monitoring in 2 (3.45%) patients, and paroxysms of atrial fibrillation or flutter were detected by intracardiac electrophysiologic investigation in 6 (22.2%). Fourteen (44.8%) patients with alcoholic heart damage demonstrated atrial vulnerability, indicative of a predisposition to atrial fibrillation even at earlier stages of alcoholic heart damage. 相似文献
996.
997.
Geoffrey G. Hallock M.D. 《Aesthetic plastic surgery》1989,13(4):285-289
Reconstitution of the nasal scaffolding with maintainence of soft tissue proportions either following severe facial trauma or as a sequela to aesthetic rhinoplasty misadventures frequently is best achieved using the stability afforded by bone grafts. Split cranial bone grafts offer many advantages and may be the donor site of choice, and may even allow such surgery to be performed on an outpatient basis in some cases. The use of miniplate or screw osteosynthesis, now commonly accepted as a superior technique in craniomaxillofacial procedures, may simplify fixation of these calvarial nasal bone grafts with an apparent decrease in the risk of resorption. 相似文献
998.
The epidemiology of viral hepatitis in US Navy enlisted personnel was reviewed for the years 1975-1984. Hospital discharge summaries of all active duty enlisted personnel admitted to a US Navy treatment facility were used for the study. From 1975 to 1984, total first hospitalizations for viral hepatitis declined from 128 per 100,000 personnel (95% confidence interval (Cl) 118-139) to 56 per 100,000 personnel (95% Cl 50-63). The highest incidence of acute viral hepatitis (115 per 100,000 personnel) was found in the youngest age groups aged 24 years and less. Risk factors for acute hepatitis included a previous hospitalization with either drug abuse (relative risk = 363) or a sexually transmitted disease (relative risk = 25) listed among the discharge diagnoses. Having a medical job classification was also associated with an increased risk of acute hepatitis. The steep decline in the incidence of viral hepatitis during this 10-year period may have been due to decreasing drug abuse in the US Navy. Immunization of high-risk groups in the US Navy with hepatitis B vaccine could be an effective policy for the prevention of acute viral hepatitis. 相似文献
999.
1000.