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11.
目的:比较国产和进口的3种口服补钙剂对健康志愿者的生物等效性。方法:10名健康志愿者随机4组交叉,不服药或po单剂量1000mg元素钙的补钙剂后,采集测定8h内的血清钙浓度和24h内的尿钙浓度。结果:空白和服用制剂A,B,C后的血清药-时曲线下面积AUC0h~8h分别为(674.2±49.08)mg·h·L-1,(728.7±42.47)mg·h·L-1,(717.5±51.34)mg·h·L-1,(697.3±52.73)mg·h·L-1;0h~4h和0h~24h尿钙排泄量分别为(13.06±9.88)mg,(65.20±24.97)mg;(34.07±17.67)mg,(138.25±57.35)mg;(34.11±25.97)mg,(147.41±85.79)mg,(25.77±12.49)mg,(99.37±48.20)mg。结论:经统计学判定,本方法检测可见,服用制剂A,B,C后血钙浓度和尿钙排量与不服药组有明显差异,但3种制剂间无显著性差异。表明国产和进口的钙制剂对体内钙行为的影响是一致的。 相似文献
12.
微量元素和人体免疫功能 总被引:7,自引:0,他引:7
施咏梅 《中华临床营养杂志》2004,12(1):66-71
微量元素对正常免疫功能的维持具有重要作用。反复感染时不仅有免疫功能受损,而且伴有多种微量元素缺乏或失衡,临床上及时补充多种维生素、微量元素制剂,能改善免疫功能,防治反复感染。 相似文献
13.
中国成年居民营养补充剂的消费现状 总被引:11,自引:0,他引:11
目的:分析我国成年居民使用营养补充剂的现状,为有针对性地制定干预策略和相关政策提供基础资料。方法:使用2002年中国居民营养与健康状况调查数据,对53159名18岁及以上居民的营养补充剂使用率及其中钙制品、铁剂、维生素和其他保健食品的使用率进行分析。结果:我国18岁及以上居民营养补充剂的使用率为5.1%,其中钙制品、铁剂、维生素和其他保健食品的使用率分别为3.4%、1.3%、2.4%和2.2%。营养补充剂的使用率表现为城市高于农村,女性高于男性,60岁及以上年龄组、45-59岁年龄组、18-44岁年龄组使用率依次降低。结论:我国成年居民中使用营养补充剂尚不普遍。 相似文献
14.
《Nutrition (Burbank, Los Angeles County, Calif.)》2014,30(6):713-718
ObjectivesThe aim of this study was to evaluate the flavonoid content of an ethanolic leaf extract from the medicinal plant Rourea induta Planch. (RIEE) and to investigate its hepatoprotective potential and in vivo antioxidant effects.MethodsUsing samples from carbon tetrachloride-treated Wistar female rats treated orally with or without RIEE, we evaluated the aspartate aminotransferase, alanine aminotransferase, and total bilirubin levels in plasma; the levels of the hepatic oxidative stress markers catalase, superoxide dismutase, glutathione peroxidase, and reduced glutathione in liver homogenates; and the thiobarbituric acid reactive substance levels. A histopathology study was performed. A quantitative analysis of the RIEE extract was performed using high-performance liquid chromatography to evaluate its flavonoid content.ResultsOral administration of RIEE significantly reduced carbon tetrachloride-induced elevations in the levels of plasma markers of hepatic damage and lipid peroxidation. It also rescued histopathologic alterations observed in the liver and levels of oxidative stress markers.ConclusionsRIEE exhibits antioxidant and hepatoprotective activities in vivo, which may be attributable to its flavonoids composition [hyperin (2), quercetin-3-O-β-xyloside (4), quercetin-3-O-α-arabinofuranoside (5), and quercetin (6)]. 相似文献
15.
《Drug testing and analysis》2018,10(2):350-356
Consumption of Ephedra alkaloids is prohibited in‐competition by the World Anti‐Doping Agency (WADA). In Taiwan, colds are often treated with Chinese herbal formulae containing Herba Ephedrae. We screened products sold in Taiwan and preliminarily assessed their relationships with WADA threshold violations. Fifty‐six concentrated powder products, including 19 Chinese herbal formulae that contained Herba Ephedrae, were collected. The content of Ephedra alkaloids, namely ephedrine (E), methylephedrine (ME), norpseudoephedrine (NPE; cathine), pseudoephedrine (PE), and norephedrine (NE; phenylpropanolamine), was determined using a validated high‐performance liquid chromatography method. The results revealed that the phenotypic indicators of the collected products, E/PE and E/total ratios, were 1.52–4.70 and 0.49–0.72, respectively, indicating that the Herba Ephedrae species in these products was probably E. sinica or E. equisetina, but not E. intermedia. The contents of E, ME, NPE, PE, and NE and the total alkaloid contents in the daily doses of the products were 0.45–34.97, 0.05–4.87, 0.04–3.61, 0.15–12.09, and 0.01–2.00 mg and 0.68–53.64 mg, respectively. The alkaloid contents followed a relatively consistent order (E > PE > ME ≈ NPE > NE), even for products from different manufacturers. We calculated that single doses of 50.0% and 3.6% of the products would result in the WADA thresholds of E and NPE being exceeded, respectively. Our data provide critical information for athletes and medical personnel, who should be wary of using complex Chinese herbal formulae in addition to over‐the‐counter products. 相似文献
16.
17.
《Environmental and molecular mutagenesis》2018,59(5):416-426
Black cohosh extract (BCE) is a widely used dietary supplement marketed to women to alleviate symptoms of gynecological ailments, yet its toxicity has not been well characterized. The National Toxicology Program (NTP) previously reported significant increases in micronucleated erythrocytes in peripheral blood of female Wistar Han rats and B6C3F1/N mice administered 15–1,000 mg BCE/kg/day by gavage for 90 days. These animals also developed a dose‐dependent nonregenerative macrocytic anemia characterized by clinical changes consistent with megaloblastic anemia. Both micronuclei (MN) and megaloblastic anemia can arise from disruption of the folate metabolism pathway. The NTP used in vitro approaches to investigate whether the NTP's test lot of BCE, BCEs from various suppliers, and root powders from BC and other cohosh species, were genotoxic in general, and to gain insight into the mechanism of action of BCE genotoxicity. Samples were tested in human TK6 lymphoblastoid cells using the In Vitro MicroFlow® MN assay. The NTP BCE and a BC extract reference material (XRM) were tested in the MultiFlow® DNA Damage assay, which assesses biomarkers of DNA damage, cell division, and cytotoxicity. The NTP BCE and several additional BCEs were tested in bacterial mutagenicity assays. All samples induced MN when cells were grown in physiological levels of folic acid. The NTP BCE and BC XRM produced activity patterns consistent with an aneugenic mode of action. The NTP BCE and five additional BCEs were negative in bacterial mutagenicity tests. These findings show that black cohosh preparations induce chromosomal damage and may pose a safety concern. Environ. Mol. Mutagen. 59:416–426, 2018. © 2018 Published 2018. This article is a US Government work and is in the public domain in the USA. 相似文献
18.
P Fürst 《Journal of the American College of Nutrition》2013,32(4):310-323
The uremic syndrome is multifactorial, and affects most tissues and organs. Disturbances in protein and amino acid metabolism may play important roles, especially in chronic uremia, either directly or by production of toxic metabolites, with resultant negative nitrogen (N) balance, muscle wasting, reduced protein synthesis, and characteristically abnormal intracellular free amino acid concentrations. There are also grossly abnormal amino acid levels in the plasma of uremic patients, e.g., increases in conjugated amino acids, high levels of several nonessential and low levels of essential amino acids. The ratios of tyrosine/phenylalanine and of valine/glycine are decreased. The low tryptophan levels may contribute to encephalopathy as a result of an imbalance in neurotransmitter synthesis. Citrulline is found in excess; the explanation is unresolved. There are elevated concentrations of the sulfur-containing amino acids: cystine, taurine, cystathionine, and homocysteine. Excess of the latter is implicated in the atherogenesis of renal failure. Disturbed metabolism and interorgan exchange of amino acids in the uremic state explains some of the abnormalities in tissue and plasma concentrations of individual amino acids. Enzymatic defects are involved in the disturbed metabolism of branched chain amino acids (BCAA), with possible antagonism among them, which impairs growth and amino acid utilization. Carbohydrate intolerance, associated with insensitivity of peripheral tissues to insulin and hyperinsulinemia, elicits decreased plasma BCAA. Protein synthesis rates in normal and pathological conditions are more closely related to the intracellular amino acid pool than to plasma amino acid levels. Concentrations of individual amino acids in the plasma pool are poor indicators of their intracellular concentrations. Muscle contains the largest pool of protein and free amino acids in the body. In chronic renal failure patients, the intracellular concentrations of valine, threonine, lysine, and carnosine are low. With low protein diets and in hemodialysis, serine, tyrosine, and taurine often are also low. The low taurine may be related to fatigue and to uremic cardiomyopathies. The commonly used amino acid supplements generally fail to correct the intracellular amino acid deficits. A “New Formula” has been developed to correct these intracellular amino acid abnormalities, and to supplement a low protein diet. It provides more valine than leucine, increased tyrosine and threonine, and less histidine, leucine, isoleucine, lysine, methionine, and phenylalanine than in formulas customarily used for patients with chronic renal failure. It is uncertain whether other ap 相似文献
19.
《International journal of food sciences and nutrition》2013,64(3):293-299
AbstractMany reports have shown promising beneficial effects of long-chain polyunsaturated fatty acids (L-PUFAs) of the omega 3 series in several brain diseases. In the present study, we tested the hypothesis that omega 3 fatty acids supplement reduced pro-inflammatory functions in vitro and in vivo. We demonstrated that a supplement rich in PUFAs (SRP) increased cell viability in a dose-dependent manner suggesting its protective role against lipopolysaccharide (LPS)-induced cell death in BV2 microglial cell line. In the same cultures, the supplement rich in PUFAs reduced the reactive oxygen species (ROS) and nitric oxide (NO) production. A most prominent target for ROS management is the family of peroxisome proliferator-activated receptors (PPARs). The co-treatment with SRP and LPS increased significantly the nuclear immunoreactivity of PPAR-γwhen compared the LPS treatment alone. Moreover, the chronic administration of the SRP in rats, increased the immunoreactivity of the PPAR-γ1 protein confirming its potential neuroprotective effect. 相似文献
20.
R. Stafford M.D. Farrar R. Kift M.T. Durkin J.L. Berry A.R. Webb L.E. Rhodes 《The British journal of dermatology》2010,163(4):817-822
Background Photosensitivity disorders involve an abnormal skin reaction to sunlight exposure and affect a substantial percentage of the population. No previous studies have directly compared lifestyle attributes between photosensitive and healthy individuals. Objectives To assess the impact of photosensitivity on time spent outdoors in the U.K., holiday behaviour, use of sunscreens and vitamin D supplements, and employment status. Methods Questionnaires were completed by ambulant photosensitive and healthy adults aged 18–60 years residing in Greater Manchester. Results Forty‐five adults with moderate–severe photosensitivity and 124 healthy adults completed the questionnaire. This revealed that photosensitive subjects spent significantly less time outdoors in the U.K. on both summer weekdays (P < 0·01) and summer weekends (P < 0·0001) than healthy subjects, took fewer holidays per year (P < 0·05), and spent less time outdoors on a sunny holiday (P < 0·0001). They wore clothing that covered a wider skin area (P < 0·0001), and use of sunscreen was greater (both frequency of application and area covered) in the photosensitive group outside of holiday time (P < 0·0001), but not when on a sunny holiday, as healthy people increased their sunscreen use at this time. Despite the reduced sun exposure, photosensitive subjects were no more likely to take vitamin D supplements than healthy subjects were; they also exhibited a significantly higher rate of unemployment (P < 0·05). Conclusions Photosensitivity disorders negatively influence lifestyle including employment status; more attention is required to the socioeconomic impact of these conditions. 相似文献