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The effect of chemical shift on magnetic resonance (MR) imaging of the pituitary fossa was studied. Healthy volunteers underwent conventional MR imaging of the pituitary fossa and then imaging with the frequency-encoding gradient reversed or with the phase- and frequency-encoding gradients interchanged. Comparison of the image pairs in each subject showed that the thin, black stripe evident at the water-fat interface within the pituitary fossa was altered when the gradients were changed. Therefore, the low-intensity signal within the pituitary fossa is a chemical shift misregistration effect. 相似文献
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Distribution of ferritin, transferrin and lactoferrin in breast carcinoma tissue. 总被引:3,自引:0,他引:3 下载免费PDF全文
An immunoperoxidase staining technique was used for detecting three major iron binding proteins (ferritin, transferrin and lactoferrin) in 40 breast carcinoma cases and six benign breast proliferative lesions. Ferritin staining was detected mainly in connectival stroma and in histiocytes surrounding neoplastic cells. Few and faint ferritin positivities were also detected in neoplastic cells of 20 carcinoma cases. Transferrin was found inconsistently in myoepithelial cells surrounding normal ductules, or around neoplastic ducts of ductal in situ carcinoma. In eight carcinoma cases, transferrin staining was also positive in neoplastic cells. Lactoferrin was detected only in normal breast epithelial cells and in benign breast proliferative lesions. These immunohistochemical findings may suggest that raised serum ferritin concentrations in breast carcinoma patients might be attributed to stromal reaction rather than to tumour synthesis. Transferrin staining of neoplastic cells in these carcinoma cases appears to be very intriguing, particularly since transferrin is considered an obligate requirement for growing cells, and transferrin receptors have been demonstrated only in dividing cells. On the basis of the immunohistochemical data, lactoferrin might be used as a pointer to benign lesions. 相似文献
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Familial occurrence of gastric cancer in the 2-year experience of a population-based registry 总被引:17,自引:0,他引:17
G Zanghieri C Di Gregorio C Sacchetti R Fante R Sassatelli G Cannizzo A Carriero M Ponz de Leon 《Cancer》1990,66(9):2047-2051
The authors studied the familial occurrence of tumors in 154 individuals with gastric cancer by reviewing the clinical data and the genealogical tree of all patients registered in 1986 through 1987 in the Local Health Care District of Modena, Italy, for cancer of the stomach. Crude and age-adjusted (world population) incidence rates of gastric cancer were 34.0 and 21.4 new cases/100,000/year, respectively, in men, and 24.5 and 10.9 in women, respectively. Among first-degree relatives of the registered patients there were 30 cases of gastric carcinoma versus 15 cases in a control group matched for age and sex (Mantel-Haenszel odds ratio [M-H OR] 3.14, P less than 0.01). This excess of gastric neoplasms was observed in siblings (17 versus 7, M-H OR 4.33, P less than 0.02) but not in parents (13 versus 8, not significant). Besides gastric cancer, there was no significant excess of other type of tumors in case families. The familial occurrence of gastric cancer tended to be more frequent in patients with "diffuse" carcinoma (52%) than in subjects with "intestinal" cancer (33%), although the difference was not statistically significant. In conclusion, the current investigation suggests that a "family history" for gastric neoplasms is usually observed in approximately 10% to 15% of the registered cases. As already described for other common malignancies, therefore, the familial occurrence of gastric carcinoma suggests the existence of a genetic susceptibility to cancer of the stomach, at least in a fraction of these patients. 相似文献
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A Di Massa R Cappelletti D Carriero O Pede A Cozzolino 《Minerva anestesiologica》1999,65(7-8):555-559
The aim of this work was to explain the reasons of two unsuccessful blocks of sciatic nerve even if anaesthetic solution was injected through insulated needle on elicited twitch. The clinical cases were two outpatients undergoing diagnostic arthroscopy of knee under anaesthetic block of sciatic and femoral nerves. In both patients, the muscular twitch appeared when the ischiatic bone was kept in unexpected touch with needle tip. In spite of the attempt to locate correctly the needle (the touch with bone means that the nerve is not in front of the needle tip), the injection of anaesthetic solution was unsuccessful. In clinical environment, when electroinsulated needles gathered total amount of administered current on the needle tip, it was not possible to elicit a twitch just at the moment of touch of the needle with the bone. Referred events disagree with some experimental works performed out of clinical environment, which found that total amount of administered current through an insulated needle gathers always in front of the tip. Our clinical observations seems to confirm an electrolocation mistake called "electrical shadow". The ability of sheathed needles to work as occasional capacitor due to the alternation of two conductor layers (needle shaft and tissue) and of a dielectric (coating material) can explain some missing electrolocations, as the appearance of electric fields within dielectric needle sheathing. 相似文献
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Elio Ricchi M.D. Salvatore Fundarò M.D. Andrea Spallanzani M.D. Alfonso Carriero M.D. Alberto Farinetti M.D. Francesco Ferrara M.D. Carlo Pezcoller M.D. 《Diseases of the colon and rectum》1996,39(3):353-357
PURPOSE: Loss of a certain amount of cutaneous tissue of the perineal region may be remedied by first intention with creation of cutaneous flaps, thus preventing second intention healing. METHODS: We present three emblematic cases in which the posterior perineal region was reconstructed by means of vertical subcutaneous pedicle flaps, subsequent to cutaneous tissue loss after surgery for extensive condilomas or neoplastic pathologies. RESULTS: Tissue loss was repaired by means of a V-Y type vertical subcutaneous pedicle flap, constructed laterally of the extirpation zone and advanced in a median direction. In all cases, no ischemia or infection of flaps occurred; sphincteral continence and long-term aesthetic results have proved to be satisfactory. CONCLUSIONS: Vertical pedicle subcutaneous flaps are well vascularized, extremely mobile, and easy to perform and have no serious postoperative complications. 相似文献
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Anisha Mahajan Jess Haines Alex Carriero Jaimie L. Hogan Jessica Yu Andrea C. Buchholz Alison M. Duncan Gerarda Darlington David W. L. Ma 《Nutrients》2022,14(10)
There is limited research on the intake of non-nutritive sweeteners (NNS) among preschool-aged children. Canada’s Food Guide suggests limiting intake of NNS for all population groups and Health Canada recommends that young children (<2 years) avoid consuming beverages containing NNS. The aim of this study was to investigate the frequency and type of non-nutritive sweetener (NNS) intake in preschool-aged children participating in the Guelph Family Health Study pilots. Parents (n = 78 families) completed 3-day food records (n = 112 children; n = 55 females, n = 57 males; 3.6 years ± 1.3). Nineteen children (17%) reported consumption of foods or beverages containing NNS. Food sources with NNS included: freezies, oral nutritional supplements, flavored water, carbonated drinks, sugar free jam and protein powder. The majority of NNS contained in these foods were identified as stevia leaf extract, acesulfame K, sucralose, monk fruit extract and aspartame. Future research should continue to study NNS intake patterns longitudinally in children and examine the association of NNS intake with diet quality and health outcomes. 相似文献
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