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61.
Infertility is a growing public health problem. Consumption of antioxidant bioactive food compounds (BFCs) that include micronutrients and non-nutrients has been highlighted as a potential strategy to protect against oxidative and inflammatory damage in the male reproductive system induced by obesity, alcohol, and toxicants and, thus, improve spermatogenesis and the fertility parameters. Paternal consumption of such dietary compounds could not only benefit the fathers but their offspring as well. Studies in the new field of paternal origins of health and disease show that paternal malnutrition can alter sperm epigenome, and this can alter fetal development and program an increased risk of metabolic diseases and breast cancer in adulthood. BFCs, such as ascorbic acid, α-tocopherol, polyunsaturated fatty acids, trace elements, carnitines, N-acetylcysteine, and coenzyme Q10, have been shown to improve male gametogenesis, modulate epigenetics of germ cells, and the epigenetic signature of the offspring, restoring offspring metabolic health induced by stressors during early life. This indicates that, from a father’s perspective, preconception is a valuable window of opportunity to start potential nutritional interventions with these BFCs to maximize sperm epigenetic integrity and promote adequate fetal growth and development, thus preventing chronic disease in adulthood.  相似文献   
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63.
作为肠外营养的重要组成部分,脂肪乳剂具有避免必需脂肪酸缺乏和作为高密度能量来源的作用。选择脂肪乳剂非常复杂,主要是因为不同的脂肪乳剂由不同的脂肪酸构成,可通过不同途径改变机体的免疫反应。同时其生物化学特性不同,对炎症反应有明显影响。应依据患者的代谢状态选择脂肪酸的类型和脂肪乳剂的供给量。越来越多的证据提示,对处于高代谢状态的危重患者,应避免使用以大豆油为原料的标准脂肪乳剂,而选择含中链甘油三酯、橄榄油或鱼油的脂肪乳剂,以减少具有促进炎症反应和免疫抑制作用的ω-6多不饱和脂肪酸的比例。尽管目前证据尚不足以作出对某种脂肪乳剂的特殊推荐意见,但作为二十碳五烯酸和二十二碳六烯酸的来源,含鱼油的脂肪乳剂能更好地调节免疫反应,对减少危重患者住ICU时间有重要作用。  相似文献   
64.
目的 观察眼内硅油填充2至5年严重乳化,硅油抽出联合白内障摘出人工晶状体植入,术中和术后情况.方法 对于25例(26眼)硅油眼内填充2~5年后严重乳化者,先冲洗出前房硅油乳化油滴,及进行房角分离术,再行晶状体超声乳化吸出术,缝合角膜切口,再经巩膜切口抽吸硅油,查看视网膜情况后,最后经角膜切口植入人工晶状体.结果 术后随访6 ~18个月,角膜均未见水肿或失代偿.眼压升高12例(12眼),噻吗心安滴眼,2周后眼压恢复正常.均未出现视网膜再次脱离或人工晶状体移位,术后视力均较术前提高.结论 对于严重硅油乳化且无法观察眼底者要及时取出硅油,手术步骤的安排和手术技巧是成功的关键,而且必须联合晶体摘出,减少再次手术.  相似文献   
65.
目的研究两种丁酸氯维地平制剂在大鼠体内的药动学特点。方法将24只大鼠随机均分为4组,分别静脉滴注低、中、高剂量的丁酸氯维地平受试制剂及参比制剂,采用HPLC法测定全血中的丁酸氯维地平,计算药动学参数,评价其在大鼠体内的药动学特点。结果丁酸氯维地平低、中、高剂量受试制剂和参比制剂在大鼠血浆中的主要药动学参数为:Cmax分别为46.16±10.65、82.99±9.34、177.80±38.32、80.31±3.04 ng·m L-1;AUC0-t分别为2.309±0.628、4.221±0.988、9.339±1.759、3.968±0.411 min·μg·m L-1;t1/2分别为12.20±4.65、16.74±6.93、15.13±4.81、18.34±4.43 min。结论丁酸氯维地平受试制剂和参比制剂在大鼠体内药动学参数差异无统计学意义,受试制剂在0.36~3.24 mg·kg-1剂量范围内呈非线性动力学特征。  相似文献   
66.
在“渐进前沿模型”的基础上 ,建立并推导了乳状液膜法提取青霉素的非稳态传质数学模型。实验条件下乳状液膜法提取青霉素的过程属扩散控制 ,其阻力主要来源于膜相。青霉素在膜相中的扩散是提取过程的速控步骤  相似文献   
67.
Artificial sweeteners (ASs) are calorie-free chemical substances used instead of sugar to sweeten foods and drinks. Pregnant women with obesity or diabetes are often recommended to substitute sugary products with ASs to prevent an increase in body weight. However, some recent controversy surrounding ASs relates to concerns about the risk of obesity caused by a variety of metabolic changes, both in the mother and the offspring. This study addressed these concerns and investigated the biodistribution of ASs in plasma and breast milk of lactating women to clarify whether ASs can transfer from mother to offspring through breast milk. We recruited 49 lactating women who were provided with a beverage containing four different ASs (acesulfame-potassium, saccharin, cyclamate, and sucralose). Blood and breast milk samples were collected before and up to six hours after consumption. The women were categorized: BMI < 25 (n = 20), BMI > 27 (n = 21) and type 1 diabetes (n = 8). We found that all four ASs were present in maternal plasma and breast milk. The time-to-peak was 30–120 min in plasma and 240–300 min in breast milk. Area under the curve (AUC) ratios in breast milk were 88.9% for acesulfame-potassium, 38.9% for saccharin, and 1.9% for cyclamate. We observed no differences in ASs distributions between the groups.  相似文献   
68.
While the history of nutrition support dates to the ancient world, modern home parenteral and enteral nutrition (HPEN) has been available since the 1960s. Home enteral nutrition is primarily for patients in whom there is a reduction in oral intake below the amount needed to maintain nutrition or hydration (i.e., oral failure), whereas home parenteral nutrition is used for patients when oral-enteral nutrition is temporarily or permanently impossible or absorption insufficient to maintain nutrition or hydration (i.e., intestinal failure). The development of home delivery of these therapies has revolutionized the field of clinical nutrition. The use of HPEN appears to be increasing on a global scale, and because of this, it is important for healthcare providers to understand all that HPEN entails to provide safe, efficacious, and cost-effective support to the HPEN patient. In this article, we provide a comprehensive review of the indications, patient requirements, monitoring, complications, and overall process of managing these therapies at home. Whereas some of the information in this article may be applicable to the pediatric patient, the focus is on the adult population.  相似文献   
69.
Dried mushrooms might be a source of mineral components, which are indispensable for human health. The aim of this study was to determine the contents of calcium (Ca), magnesium (Mg), iron (Fe), zinc (Zn), copper (Cu), manganese (Mn), and selenium (Se) in dried wild-grown mushrooms (Boletus edulis and Xerocomus badius) available for sale, and to evaluate these mushrooms’ contribution to the daily reference intake of the studied bioelements. The concentrations of mineral components in the mushroom samples were determined by the flame method (Ca, Mg, Fe, Zn, Cu, Mn) and the electrothermal (Se) atomic absorption spectrometry method. The mean Ca, Mg, Fe, Zn, Cu, Mn (in mg/kg), and Se concentrations (in µg/kg) in B. edulis were 82.1, 964.1, 233.4, 97.9, 25.3, 22.1, and 6501.6, respectively, whereas in X. badius: 67.5, 1060.2, 87.8, 197.2, 33.9, 19.8, and 282.4, respectively. We have shown that dried B. edulis can be considered a source of Se. In the case of the other microelements, the tested mushrooms may serve only as additional supplements. Therefore, the studied species of mushrooms cannot be regarded as potential nutritional sources of the macroelements in question. Consumers should be properly informed about this, which should be guaranteed by appropriate legal regulations.  相似文献   
70.
Background: Excess body adipose tissue accumulation is a common and growing health problem caused by an unbalanced diet and/or junk food. Although the effects of dietary fat and glucose on lipid metabolism regulation are well known, those of essential amino acids (EAAs) have been poorly investigated. Our aim was to study the influence of a special diet containing all EAAs on retroperitoneal white adipose tissue (rpWAT) and interscapular brown adipose tissue (BAT) of mice. Methods: Two groups of male Balb/C mice were used. The first was fed with a standard diet. The second was fed with an EAAs-rich diet (EAARD). After 3 weeks, rpWAT and BAT were removed and prepared for subsequent immunohistochemical analysis. Results: EAARD, although consumed significantly less, moderately reduced body weight and BAT, but caused a massive reduction in rpWAT. Conversely, the triceps muscle increased in mass. In rpWAT, the size of adipocytes was very small, with increases in leptin, adiponectin and IL-6 immunostaining. In BAT, there was a reduction in lipid droplet size and a simultaneous increase in UCP-1 and SIRT-3. Conclusions: A diet containing a balanced mixture of free EAA may modulate body adiposity in mice, promoting increased thermogenesis.  相似文献   
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