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排序方式: 共有759条查询结果,搜索用时 343 毫秒
81.
Maike Timm‐Heinrich Xuebing Xu Nina Skall Nielsen Charlotte Jacobsen 《European Journal of Lipid Science and Technology》2003,105(8):436-448
Traditional sunflower oil (SO), randomized lipid (RL) and specific structured lipid (SL), both produced from SO and tricaprylin/caprylic acid, respectively, were stored for up to 12 wk to compare their oxidative stabilities by chemical and sensory analyses. Furthermore, the effect of adding a commercial antioxidant blend Grindox 117 (propyl gallate/ citric acid/ascorbyl palmitate) or gallic acid to the SL was investigated. The lipid type affected the oxidative stability: SL was less stable than SO and RL. The reduced stability was most likely caused by both the structure of the lipid and differences in production/ purification, which caused lower tocopherol content and higher initial levels of primary and secondary oxidation products in SL compared with RL and SO. Grindox 117 and gallic acid did not exert a distinct antioxidative effect in the SL oil samples during storage. 相似文献
82.
B N Jacobsen D Kjersgaard M Winther-Nielsen K Gustavson 《Water science and technology》2004,50(5):37-43
Influent--effluent monitoring by comprehensive chemical analyses was conducted at the Avedoere wastewater treatment plant (WWTP) during 2002. In one programme, the same samples were tested for algal toxicity by the ISO 8692 method. Based on evaluation of 17 hazardous substances (including 7 heavy metals), there was a quite good agreement between calculated and measured toxic units. In another programme, influent--effluent monitoring for 11 pharmaceuticals and specific hormones showed high removal rates, except for sulphamethizol and furosemide. High removal is probably due to WWTP operation with long SRTs. Effluent biomonitoring of freshwater mussels showed only bioaccumulation for: diethylphthalate, LAS, EOX as well as Cr and Ni. Surprisingly, no bioaccumulation could be observed for 100 other specific organic compounds and 8 other heavy metals (including Hg, Cd and Pb). 相似文献
83.
PB Jacobsen MR Widows DM Hann MA Andrykowski LE Kronish KK Fields 《Canadian Metallurgical Quarterly》1998,60(3):366-371
Hormonal treatments which have an androgenic effect have the potential to cause vocal changes. The changes in vocal fold structure and voice quality are considered to be irreversible. To date, studies have documented subjective vocal changes or documented single cases without detailed, baseline voice assessments. The impact on laryngeal function of women taking these androgenic treatments requires further detailed, objective assessment. The need for increased awareness of the actions of androgenic hormones on womens' voices, and the benefits of a thorough voice assessment are discussed. 相似文献
84.
The aim of the study was the definition of the clinical features and survival of 27 resected cases of distal bile duct carcinoma. This neoplasm accounted for 14% of all periampullary malignancies treated by pancreaticoduodenectomy between 1990 and 1996. Jaundice was present in 96% of patients, but was the first symptom only in 78%. Preoperative investigations allowed to recognize distal bile duct cancer in a minority of patients (41%). Operative mortality and morbidity were 3.7 and 44%, respectively. Most patients (88%) were assigned to UICC stage IV-A. Postoperative survival was not significantly better than survival of 101 patients undergoing pancreaticoduodenectomy for pancreatic ductal carcinoma; median survival was 22 months, with a 13% 5-year survival rate. Determinants of a better prognosis were UICC stage 相似文献
85.
TA Nicklas L Myers C Reger B Beech GS Berenson 《Canadian Metallurgical Quarterly》1998,98(12):1432-1438
OBJECTIVE: To evaluate the impact of breakfast consumption patterns on the nutritional adequacy of diets of young adults and determine possible ethnic and gender differences. DESIGN AND SETTING: Cross-sectional survey of young adults in Bogalusa, La. SUBJECTS: Twenty-four-hour dietary recalls were collected from October 1988 through October 1991 on 504 young adults (mean age=23 years, 58% women, 70% white). STATISTICS: Analysis of variance and logistic regression techniques were used to investigate the relationship of breakfast consumption, ethnicity, and gender on dietary adequacy. The P values are from an analysis of variance model that adjusted for gender and ethnicity. RESULTS: Thirty-seven percent of young adults skipped breakfast. Of those who ate breakfast, 75% ate at home, 10% ate a fast-food breakfast, and 15% reported other sources. Mean energy intake from breakfast was 485 kcal; men consumed more energy than women (P<.001), and blacks consumed more energy than whites (P<.01). The breakfast meal provided an average of 13% of energy from protein, 55% from carbohydrate, 14% from sucrose, 34% from fat, and 12% from saturated fat. Whites consumed a breakfast higher in carbohydrate and sucrose than blacks, who consumed a breakfast higher in fat and saturated fat. Variations in breakfast foods consumed explained the racial differences in the nutrient composition of the breakfast meal. Young adults who skipped breakfast had lower total daily intakes of energy (P<.0001), protein per 1,000 kcal (P<.05), and saturated fat per 1,000 kcal (P<.01) than those who consumed breakfast. For all vitamins and minerals studied, a higher percentage of young adults who skipped breakfast did not meet two thirds of the Recommended Dietary Allowance than those who consumed a breakfast. APPLICATIONS: Encouraging consumption of breakfast, along with selection of more healthful breakfast food choices or snacks that are culturally appropriate, may be important strategies for improving the nutritional quality of young adults' diets. 相似文献
86.
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88.
Ochratoxin A concentrations in rye and wheat in Denmark for 1992-99 are reported. The results show that the concentration of ochratoxin A is higher in rye than in wheat for both conventionally and organically grown rye and wheat. The levels in organically grown rye are higher than in conventionally grown based on multiyear mean contents. However, the difference between the two groups of cereals has decreased since the Danish food-monitoring system for ochratoxin A was started in 1986; 2.0% of all samples exceeded the Danish maximum limit of 5 µg kg -1 introduced in 1995. For rye samples, 3.2% exceeded the maximum limit, and for wheat samples, 0.5% exceeded the maximum limit. 相似文献
89.
We report here a case in which for hemoptysis during menstruation (catamenial hemoptysis) right middle lobectomy was performed thoracoscopically under a preoperative diagnosis of pulmonary endometriosis with a successful outcome. The patient was a 27-year-old housewife who from the age of 24 years experienced hemoptysis during menstruation, and was diagnosed as having pulmonary endometriosis on the basis of detailed examinations including bronchoscopy and chest CT. From the age of 26 years hormone therapy was administered, but the hemoptysis recurred with the menstruation following its cessation. After admission to this department bronchoscopy performed at the time of menstruation revealed bleeding from right B4 while chest CT showed an abnormal shadow in right S4 b. Right middle lobectomy was then performed thoracoscopically under a diagnosis of right middle lobe endometriosis. In the resected specimen findings of pulmonary hemosiderosis, granulomatous phlebitis and micrometastases from a thyroid cancer were noted. The postoperative course was favorable with no further episodes of hemoptysis occurring. In this case histological proof of endometriosis could not be obtained, but the diagnosis of pulmonary endometriosis was strongly suggested by the clinical course and objective findings such as pulmonary hemosiderosis. 相似文献
90.
Alan R. Jacobsen 《Color research and application》1986,11(4):263-269
The effect of background raster luminance on the ability to learn and recall color-coded information was studied via a paired-associates paradigm. Twenty variously colored circles, paired with two-digit numbers, were presented on a color-graphics CRT terminal. On test trials each colored circle was presented by itself and observers were required to recall verbally the two-digit number that was previously paired with the target color. Time to recall as well as actual responses were both recorded. Two raster luminance levels were tested: dark or perceptual black and one that appeared to be a shade of middle gray. Ten out of 10 observers reached the learning criterion with the middle-gray background, while only 10 out of 15 were able to reach the criterion with the black background. In addition, those observers who reached the criterion on the black background still made significantly more errors than the observers presented with the middle-gray background. There were no significant differences, however, in time to recall between the two types of backgrounds for observers who reached the learning criterion. These results are discussed in light of the CIELUV color-difference metric AE*uv. 相似文献