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排序方式: 共有112条查询结果,搜索用时 15 毫秒
1.
This review provides an evaluation of the correlates and/or risk factors associated with disordered eating and the pursuit of muscularity among adolescent boys. One of the main conclusions is that similar factors and processes are associated with both behavioral problems. Several factors found to be consistently associated with disordered eating among boys are also similar to those found with girls. These include body mass index, negative affect, self-esteem, perfectionism, drug use, perceived pressure to lose weight from parents and peers, and participation in sports that focus on leanness. However, as many of the findings have only been verified using cross-sectional designs, prospective studies are now needed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
2.
Miia Turpeinen Jouko Uusitalo Terhi Lehtinen Marita Kailaj?rvi Olavi Pelkonen Jouni Vuorinen Pasi Tapanainen Camilla Stjernschantz Risto Lammintausta Mika Scheinin 《International journal of molecular sciences》2013,14(7):14064-14075
The objective of these investigations was to determine the possible effects of the novel selective estrogen receptor modulator, ospemifene, on cytochrome P450 (CYP)-mediated drug metabolism. Ospemifene underwent testing for possible effects on CYP enzyme activity in human liver microsomes and in isolated human hepatocytes. Based on the results obtained in vitro, three Phase 1 crossover pharmacokinetic studies were conducted in healthy postmenopausal women to assess the in vivo effects of ospemifene on CYP-mediated drug metabolism. Ospemifene and its main metabolites 4-hydroxyospemifene and 4′-hydroxyospemifene weakly inhibited a number of CYPs (CYP2B6, CYP2C9, CYP2C19, CYP2C8, and CYP2D6) in vitro. However, only CYP2C9 activity was inhibited by 4-hydroxyospemifene at clinically relevant concentrations. Induction of CYPs by ospemifene in cultured human hepatocytes was 2.4-fold or less. The in vivo studies showed that ospemifene did not have significant effects on the areas under the plasma concentration-time curves of the tested CYP substrates warfarin (CYP2C9), bupropion (CYP2B6) and omeprazole (CYP2C19), demonstrating that pretreatment with ospemifene did not alter their metabolism. Therefore, the risk that ospemifene will affect the pharmacokinetics of drugs that are substrates for CYP enzymes is low. 相似文献
3.
Yurong Ma Qingguo Wang Gyunghoon Hong Marita Cantwell 《International Journal of Food Science & Technology》2010,45(7):1486-1494
The cultivar Pacific Russet with high browning susceptibility was used for most testing. Controlled atmospheres (0.3%, 3% and 21% O2 in combination with 0%, 6% or 12% CO2) and anti‐browning chemicals were studied in relation to quality retention and wound‐induced phenolic metabolism of fresh‐cut slices for up to 16 days at 5 °C. The 3% O2+ 12% CO2 atmosphere was most effective among those tested, and retarded increases in phenolics and phenylalanine ammonia lyase activity, but had only slight benefit on visual quality. A 1.25% ascorbic acid +1.25% citric acid treatment was ineffective, but when combined with 3% O2+ 12% CO2, it was comparable with 0.025% sodium bisulphite. Bisulphite concentrations from 0.05% to 0.25% provided similar effective control of discolouration. Bisulphite as low as 0.025% with 3% O2+ 12% CO2 resulted in a visual quality score at the limit of marketability after 8 days at 5 °C. Chemical treatments did not retard increases in phenolic concentrations or phenolic enzyme activities. 相似文献
4.
This paper aims to clarify current knowledge on the contribution of communication to crisis management in the case of terrorism incidents. This is done by means of a systematic review of the scientific literature on terrorism communication over the last 10 years to identify the many challenges facing communication in such crises, and represents the first attempt of its kind. To date, within the literature on terrorism communication, much attention has been paid to chemical, biological, radiological or nuclear hazards. Terrorism crises are complex and challenging. Preparedness for such diverse low‐probability high‐impact crises can best be included in a wider educative approach. Terrorism crises call for fast information updates that, using a multi‐channel approach, can be tailored to fit different needs and (social) media habits. 相似文献
5.
Temperature‐dependent coefficient of thermal expansion (CTE) of injection molded,short‐glass‐fiber‐reinforced polymers
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A deep understanding of the anisotropic, composite‐, geometry‐, and temperature‐dependent coefficient of thermal expansion (CTE) of short‐fiber‐reinforced polymers is often needed in material development and at early stages of the design process of injection molded parts. Usually, the data available does not reflect the complex behavior and the knowledge about the influences and interactions are missing. This paper deals with a method for calculating the composite‐, geometry‐, and temperature‐dependent anisotropic CTE of parts made from short‐fiber reinforced polymers without respectively low preload to create an understanding of its origins and influential factors. Here, a good accordance between the measurements and calculations was achieved. POLYM. ENG. SCI., 55:2661–2668, 2015. © 2015 Society of Plastics Engineers 相似文献
6.
Reducing sodium intake from meat products 总被引:4,自引:0,他引:4
Sodium intake exceeds the nutritional recommendations in many industrialized countries. Excessive intake of sodium has been linked to hypertension and consequently to increased risk of stroke and premature death from cardiovascular diseases. The main source of sodium in the diet is sodium chloride. It has been established that the consumption of more than 6g NaCl/day/person is associated with an age-increase in blood pressure. Therefore, it has been recommended that the total amount of dietary salt should be maintained at about 5-6g/day. Genetically salt susceptible individuals and hypertensives would particularly benefit from low-sodium diets, the salt content of which should range between 1 and 3g/day. In industrialized countries, meat products and meat meals at home and in catering comprise one of the major sources of sodium, in the form of sodium chloride. Sodium chloride affects the flavour, texture and shelf life of meat products. The salt intake derived from meat dishes can be lowered by, whenever possible, adding the salt, not during preparation, but at the table. In most cases, salt contents of over 2% can be markedly lowered without substantial sensory deterioration or technological problems causing economical losses. Salt contents down to 1.4% NaCl in cooked sausages and 1.75% in lean meat products are enough to produce a heat stable gel with acceptable perceived saltiness as well as firmness, water-binding and fat retention. A particular problem with low-salt meat products is, however, that not only the perceived saltiness, but also the intensity of the characteristic flavour decreases. Increased meat protein content (i.e. lean meat content) in meat products reduces perceived saltiness. The required salt content for acceptable gel strength depends on the formulation of the product. When phosphates are added or the fat content is high, lower salt additions provide a more stable gel than in non-phosphate and in low-fat products. Small differences in salt content at the 2% level do not have marked effects on shelf life of the products. By using salt mixtures, usually NaCl/KCl, the intake of sodium (NaCl) can be further reduced. 相似文献
7.
Marita Wittkowski Werner Baltes Wolfhard Krönert und Rudolf Weber 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1983,177(6):447-453
Zusammenfassung Es wird eine Phasenumkehr-HPLC-Methode beschrieben, die es gestattet, dieAlternaria-Toxine Alternariol (AOH), Alternariolmonomethylether (AME), Altenuen (ALT) und Altertoxin I (ATX-I) in Obst- und Gemüseerzeugnissen mit guter Empfindlichkeit zu bestimmen. Die Ergebnisse werden dünnschichtchromatographisch abgesichert. Sie wurde an ca. 50 Handelsprodukten Bowie an ca. 20 verschimmelten Früchten erprobt. Keines der Handelsprodukte war mit den o. g. Mykotoxinen kontaminiert, während zwei der verschimmelten Proben (Äpfel) 160 ppb AOH, bzw. 250 ppb AME enthielten.
Determination of alternaria toxins in fruit and vegetable products
Summary A reverse phase HPLC method for the determination of theAlternaria mycotoxins alternariol (AOH), alternariol monomethyl ether (AME), altenuene (ALT) and altertoxin I (ATX-I) in fruit and vegetable products is described. The procedure has good sensitivity. The results are corroborated by TLC. About 50 commercial products and about 20 mouldy fruits were analysed. None of the commercial products was contaminated with the toxins whereas two of the mouldy samples (apples) contained 160 ppb AOH respectively 250 ppb AME.相似文献
8.
In light of IASB??s statement to drop stewardship as a separate objective of financial accounting and the ongoing debate about increasing the disclosure of soft information, we investigate the economic consequences of publicly reported soft information from a stewardship perspective. In an LEN model we include market price as a performance measure and investigate whether the principal benefits from disclosing additional information. While the principal can only use contractible performance measures in the contract with the agent, capital market participants can only use disclosed information when pricing firm value. We find that the disclosure of information can decrease the principal??s expected net profit. This result follows from either a noisier or a less congruent market price as a consequence of disclosing additional information. Thus, we present a rationale for partial disclosure in the absence of proprietary costs or the uncertainty of information endowment. 相似文献
9.
JR Mault EG Whitaker JS Heinle AJ Lodge WJ Greeley RM Ungerleider 《Canadian Metallurgical Quarterly》1994,57(1):96-100; discussion 100-1
During repair of congenital heart defects, extended periods of hypothermic circulatory arrest (CA) have been shown to cause short-term cerebral metabolic and flow abnormalities as well as long-term neuropsychologic dysfunction. Occasionally, a second period of CA is required during the same operative setting to revise a complicated repair. However, the metabolic effects of two consecutive periods of CA on the brain are unclear. In this study, we compared the recovery of cerebral metabolism after 60 minutes of CA with that after two sequential 30-minute periods of CA separated by a brief period of rewarming (30'SEQ). Fifteen neonatal piglets (2 to 3 kg) were placed on cardiopulmonary bypass at 100 mL.kg-1 x min-1 and cooled to 18 degrees C. Each animal then underwent either 60 minutes of uninterrupted cardiopulmonary bypass at 18 degrees C, 60 minutes of CA, or two 30-minute periods of CA separated by a brief period of rewarming. After these experimental periods, animals were rewarmed to 37 degrees C and weaned from cardiopulmonary bypass. Data were obtained before cardiopulmonary bypass and after cardiopulmonary bypass at 37 degrees C and included measurements of cerebral blood flow by xenon 133 clearance, arterial and sagittal sinus blood gases, and cerebral metabolism (mL O2.100 g-1 x min-1). Our results demonstrated that acute recovery of cerebral metabolism was significantly impaired after 60 minutes of CA and that recovery of cerebral metabolism after two sequential 30-minute periods of CA was significantly better than after 60 minutes of continuous CA.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
10.
This study examined factors that influence body image and strategies to either lose weight or increase muscle among children. Participants were 237 boys and 270 girls. Body mass index (BMI), body dissatisfaction, cognitions and behaviors to both lose weight and increase muscles, as well as self-esteem and positive and negative affect, were evaluated. Self-esteem was associated with body satisfaction, positive affect predicted strategies to lose weight and increase muscles, and negative affect predicted body dissatisfaction and cognitions to lose weight and increase muscles. Boys were more likely to focus on changing muscles. Respondents with higher BMIs were more focused on losing weight but not muscle. The discussion focuses on health risk behaviors related to eating and exercise among children. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献