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981.
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RA Benedikt JS Jelinek MJ Kransdorf RP Moser BH Berrey 《Canadian Metallurgical Quarterly》1994,4(3):485-490
To assess the effectiveness of gadopentetate dimeglumine in the magnetic resonance (MR) imaging evaluation of soft-tissue masses without osseous involvement, 30 patients underwent MR imaging before and after administration of contrast material (0.1 mmol/kg). Of the 30 lesions, 22 were benign and eight were malignant; histologic confirmation was available in all lesions except one benign lesion. Overall, enhancement was detected in 26 (87%) of 30 lesions: 18 (82%) of the 22 benign lesions and eight (100%) of eight malignant lesions. Enhancement was characterized as homogeneous (two [11%] benign lesions, two [25%] malignant lesions), inhomogeneous (11 [61%] benign lesions, six [75%] malignant lesions), or peripheral (five [28%] benign lesions, no malignant lesions). Of the 19 lesions assessed for a change in enhancement over time, seven (37%) showed an increase and two (11%) showed a decrease in signal intensity. The authors conclude that benign and malignant soft-tissue lesions could not be differentiated solely on the basis of enhancement (pattern, degree, or time course). 相似文献
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OBJECTIVE: In 1995, we presented our experience in hysteroscopic resection of hemorrhagic submucous fibroids in 196 patients. The objective of the present work was to analyze functional outcome three years later. PATIENTS: One hundred ninety-six patients with abnormal uterine bleeding were treated between 1987 and 1993. Equipment, techniques, characteristics of the procedures and early results were detailed in the previous article. RESULTS: With a mean follow-up of 73 months (range 50,104), results were: 13.8% of the patients were lost to follow-up; 68.4% had symptomatic improvement and failure was observed in 17.8% (subsequent hysterectomy in 12.7%). Forty-nine patients had repeat resection in this series; 61 became menopausal after surgery, and 21 were taking hormone replacement therapy with good results. CONCLUSION: Developed as an alternative to hysterectomy, operative hysteroscopy has proven to be a safe and effective procedure. This treatment modality appears to give satisfactory long-term results, with a low rate of complications. 相似文献
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987.
To determine the effect of age on the regulation of intestinal nutrient absorption, we fed young (7.6-mo-old) and aged (24.8-mo-old) C57BL mice diets designed to stimulate in vitro sugar or amino acid uptake in the isolated small intestine. In each age group, diet had no effect on feeding rates and body weights. D-Glucose and D-fructose uptakes by the small intestine each increased by about two times in young and 1.5 times in aged mice fed high carbohydrate diets as compared with those fed no carbohydrate. Adaptive increases in uptake by the aged group were not only reduced but also restricted to more proximal regions of the small intestine. In both age groups, diet-stimulated increases in D-glucose transport were accompanied by parallel increases in number of Na(+)-D-glucose cotransporters as estimated by specific phlorizin binding. Diet had no effect on transporter Kd for phlorizin, turnover rate of each transporter, mucosal mass or mucosal permeability. A high protein diet stimulated the uptake of L-aspartate and L-proline in young mice and of only L-aspartate in aged mice. Uptake of essential amino acids and of nonessential amino acids sharing transporters with essential ones were not regulated. Although aged mice possess adaptive mechanisms to diet that are similar to those in young mice, the effectiveness of these mechanisms may be impaired with age and may result in malabsorption symptoms so prevalent in the elderly. 相似文献
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JT Thompson CJ Hiner BM Glaser AJ Gordon RP Murphy RN Sjaarda 《Canadian Metallurgical Quarterly》1994,117(3):291-301
We evaluated the fluorescein angiographic features of full-thickness macular holes before and after vitrectomy, fluid-gas exchange, and instillation of transforming growth factor beta-2 in 43 eyes in a masked fashion to evaluate the angiographic characteristics of macular holes preoperatively and the changes that occur with successful and unsuccessful closure of the macular hole. Hyperfluorescence was present in the base of the macular hole preoperatively in 34 of 43 eyes (79.1%), was questionable in eight of 43 eyes (18.6%), and was definitely absent in only one of 43 eyes (2.3%). The hyperfluorescence in the base of the macular hole disappeared in 19 of 20 eyes (95%) with successful closure of the macular hole (P < .00001) and appeared to be caused by blocked fluorescence at the site of the macular hole. The photographic features of eyes with unsuccessful closure of the macular hole changed little, except that the size of the cuff of neurosensory detachment around the hole increased and was associated with decreased postoperative visual acuity. These angiographic changes support the presence of a glial tissue plug bridging a small defect in the fovea of eyes with successful closure of a macular hole. 相似文献
990.