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排序方式: 共有1042条查询结果,搜索用时 15 毫秒
51.
KP Morris JR Skinner C Wren S Hunter MG Coulthard 《Archives of disease in childhood》1993,68(5):637-643
Thirteen anaemic children on dialysis were assessed to determine the incidence of cardiac changes in end stage renal failure. Nine children had an increased cardiothoracic ratio on radiography. The electrocardiogram was abnormal in every case but no child had left ventricular hypertrophy as assessed by voltage criteria. However, left ventricular hypertrophy, often gross, was found on echocardiography in 12 children and affected the interventricular septum disproportionately. Cardiac index was increased in 10 patients as a result of an increased left ventricular stroke volume rather than heart rate. Left ventricular hypertrophy was significantly greater in those on treatment for hypertension and in those with the highest cardiac index. Abnormal diastolic ventricular function was found in 6/11 children. Children with end stage renal failure have significant cardiac abnormalities that are likely to contribute to the high cardiovascular mortality in this group. Anaemia and hypertension, or its treatment, probably contribute to these changes. Voltage criteria on electrocardiogram are of no value in detecting left ventricular hypertrophy. Echocardiography must be performed, with the results corrected for age and surface area, in order to detect and follow these abnormalities. 相似文献
52.
Vlassenko AG Thiessen B Beattie BJ Malkin MG Blasberg RG 《Journal of neuro-oncology》2000,46(3):249-259
Changes in [18F]-2-fluoro-2-deoxyglucose (FDG) uptake and gadopentetate dimeglumine (Gd-DTPA) enhancement before and after the first course of treatment with a cytostatic agent SU101 (N-[(4-trifluoromethyl)-phenyl]-5-methylisoxazole-4-carboxamide, SUGEN) were assessed using positron emission tomography (PET) and magnetic resonance imaging (MRI) in a pilot study of 8 patients with recurrent supratentorial malignant gliomas. The localization and the volume of Gd-DTPA enhancement and FDG hypermetabolism were analyzed. PET and MRI studies were performed one week before and 7.6±3.7 weeks after administration of SU101. The ratios of mean tumor nobreak activity to mean contralateral white matter and ipsilateral cerebellar activity were calculated for tumor regions, and SUV values corrected to the subjects' body surface area and glucose level (SUVbsa*glu) were calculated for non-tumor regions. Five patients had a substantial increase of tumor volume on both PET and MRI during the first course of SU101. PET and MRI showed roughly equivalent volume changes. Large tumor volume increases were associated with a short time to clinical progression. The metabolic change in the tumor following the first course of SU101 varied from patient to patient, ranging from a 31% reduction to a 43% increase in FDG uptake ratio. Changes in FDG uptake were not predictive of time to progression or survival. In 2 patients with marked clinical deterioration and rapid tumor growth, there were differences in localization of Gd-DTPA enhancement and FDG hypermetabolism suggesting that hypermetabolism beyond the area of contrast enhancement may be of value in predicting rapid progression of high-grade glioma. SU101 did not induce any appreciable changes in SUVbsa*glu for non-tumor brain in 6 of 8 patients. 相似文献
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54.
Screening for germ line TP53 mutations in breast cancer patients. 总被引:10,自引:0,他引:10
A L B?rresen T I Andersen J Garber N Barbier-Piraux S Thorlacius J Eyfj?rd L Ottestad B Smith-S?rensen E Hovig D Malkin 《Cancer research》1992,52(11):3234-3236
The constant denaturant gel electrophoresis technique was used to screen for TP53 germ line mutations in 237 women with breast carcinoma (167 unselected patients, 30 patients with at least one first-degree relative with breast cancer, and 40 women diagnosed with breast cancer before age 35). A germ line mutation at codon 181 was noted in one of the unselected patients and a codon 245 mutation in one of the early-onset patients. Both had a family history of breast cancer and other malignancies suggestive of Li-Fraumeni syndrome. The codon 245 mutation was also present in this patient's affected mother. 相似文献
55.
Altitude chamber experiments have shown that the quantity of oxygen consumption in the posthypoxic period as an index of adaptation to hypoxia is of a low informative value: during the normal course of adaptation, oxygen consumption changes insignificantly or decreases slightly; it increases somewhat if the hypoxic atmosphere contains CO2 (pCO2 = 19 - 27 mm Hg) and declines significantly (by 22.6%) only if adaptation is disordered. At the same time oxygen consumption can be a highly informative index, characterizing the efficiency of adaptation to hypoxia only if it is measured immediately after exposure to acute hypoxia. In this experimental design the magnitude of oxygen consumption increases with increasing oxygen debt which, as follows from our experiments, shows the degree of conditioning to altitude hypoxia. 相似文献
56.
Between June 1986 and April 1988, 86 sonographic examinations of the shoulder were performed on patients suspected of having rotator cuff tears. Major sonographic diagnostic criteria included (a) a well-defined discontinuity usually visible as a hypoechoic focus within the cuff, (b) nonvisualization of the cuff and (c) an echogenic focus within the cuff. Seventy-five patients underwent both sonography and arthrography. Compared with arthrography alone, ultrasound examinations enabled detection of 92% of rotator cuff tears (24 of 26 tears), with a specificity of 84% and a negative predictive value of 95%. Correlation was obtained in 30 of these patients who underwent surgery for rotator cuff tear or other soft-tissue abnormality. In this group, the sensitivity of sonography for detection of a tear was 93%, with a specificity of 73%, while for arthrography sensitivity was 87% and specificity was 100%. These data indicate that sonography is a useful, noninvasive screening procedure for patients suspected of having rotator cuff injury. 相似文献
57.
58.
Computed tomography of the pancreas 总被引:2,自引:0,他引:2
59.