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M A Garre J M Boles P Y Youinou 《JPEN. Journal of parenteral and enteral nutrition》1987,11(3):309-313
Protein-calorie malnutrition (PCM) adversely affects more or less all immune competent cells. Nonspecific immunity is impaired, particularly adherence and chemotaxis of phagocytes, although the responsiveness of circulating cells may not be the same as that of noncirculating cells. PCM results in numerical and functional impairment in lymphocytes. PCM markedly affects IgG class antibodies which have the highest affinity when directed against T-dependent antigens. These impairments are interrelated, since cooperation between T-helper cell and B-cells is depressed, and the antigen presentation to T-helper cells by macrophages is deficient. 相似文献
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Short-Ti inversion-recovery pulse sequence: analysis and initial experience in cancer imaging 总被引:2,自引:0,他引:2
Inversion recovery (IR), commonly considered a pulse sequence capable of producing T1-weighted images with excellent display of normal anatomy, is versatile: The null point and peak time provide a useful, succinct summary of the properties of IR and its capacity for producing both T1- and T2-weighted images. Shortening of the inversion time (TI) and creation of a short-TI inversion-recovery (STIR) pulse sequence increases sensitivity to malignancy and other abnormalities by making the effects of prolonged T1 and T2 on signal intensity additive and by nulling the signal from fat. The authors examined over 300 patients with various malignancies and compared STIR images with T1- and T2-weighted images obtained at 0.5 T. In 43 cases, signal-difference-to-noise ratios (SD/Ns) were calculated between tumor, fat, and muscle. In general, STIR images demonstrated tumor as a conspicuously high-intensity area in a background of muted, discernible anatomic detail. The good contrast achieved with STIR sequences between tumor and fat (SD/N = 18.1) and tumor and muscle (SD/N = 12.9) consolidated into a single image the information contained separately on T1- and T2-weighted images, which facilitates efficient detection and localization of malignancy. 相似文献
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D A Frambach C E Roy J L Valentine S F Boles J J Weiter C L Schepens 《Ophthalmic surgery》1988,19(2):98-100
The prevalence of cardiovascular disease (by EKG criteria) in patients with rhegmatogenous retinal detachments has been reported to be more than four times that found in age-matched controls. Adhesion between the retinal pigment epithelium (RPE) and the photoreceptors is facilitated by RPE transport. Because RPE transport is driven by a Na-K ATPase, it has been suggested that the correlation of EKG abnormalities and retinal detachment may be due to clinical use of digoxin, a Na-K ATPase inhibitor frequently given to patients with cardiovascular disease. The prevalence of EKG abnormalities in 299 consecutive patients with primary retinal detachment is about the same as that reported previously. However, 92% of these patients with EKG abnormalities did not take digoxin. Therefore, clinical use of digoxin cannot account for the reported association of EKG abnormalities and rhegmatogenous retinal detachment. 相似文献
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Sixteen cases of histopathologically proved solitary rectal ulcer syndrome were encountered. Fifteen patients underwent barium enema study; in nine cases the findings--including rectal stricture, granularity of the mucosa, and thickened rectal folds-were nonspecific. In six cases the study was normal. All patients had a long history of defecation disorders, and defecography was performed in all. In seven cases, intussusception of the rectal wall was seen; in another case the intussusception was accompanied by a rectocele. One case showed rectal prolapse. In four cases, failed relaxation of the puborectalis occurred and prevented the passage of the bolus; in another case there was abnormal perineal descent. In two patients studies were normal. In patients with defecation disorders, the possibility of this syndrome should be considered. Defecography is the method of choice for establishing the diagnosis. 相似文献
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