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2.
25种常用食物总脂质、总磷脂和主要磷脂含量的比较 总被引:1,自引:0,他引:1
<正> 磷脂是构成生物细胞膜的基本组分,以其规律的结构保证细胞的正常形态和功能。因而经常有一定质量的磷脂保证,是维持所有细胞健康生长和生理功能的基础。磷脂已被广泛应用为食品添加剂,由于磷脂是一种天然产物,更加适应当今世界对“非化学添加物”的需要。但目前的食物成分表均无磷脂的含量,为此对云南、陕西、辽宁等地常用食物中总脂质、总磷脂和主要磷脂的含量进行了分析。 相似文献
3.
《Nutrition reviews》1987,45(10):246-248
Increasing dietary 18:2 n-6/18:3 n-3 causes similar relative changes in fatty acid profiles of phosphatidylethanolamine and phosphatidylcholine from rat neural and erythrocyte membranes. 相似文献
4.
Fibrate for treatment of primary biliary cirrhosis 总被引:1,自引:0,他引:1
Shinji Iwasaki Naoaki Akisawa Toshiji Saibara Saburo Onishi 《Hepatology research》2007,37(S3):S515-S517
Recent studies of the effectiveness of ursodeoxycholic acid (UDCA) therapy in patients with primary biliary cirrhosis (PBC) reported that UDCA therapy did not necessarily stop the progression of liver fibrosis in all patients, even those with early stage PBC. Thus, there is a need for more effective treatments that could prevent asymptomatic PBC from progressing to the icteric stage. Bezafibrate is effective in approximately two-thirds of non-icteric patients who have not shown a complete response to UDCA. Serum bilirubin, aspartate aminotransferase and γ-guanosine 5'-triphosphate levelswere significantly lower in patients who responded to additional bezafibrate on univariate analysis. The putative mechanism by which bezafibrate acts in cholestasis is by increasing phospholipid output into bile, which forms micelles with the hydrophobic bile acid that reduces its toxicity. 相似文献
5.
C. F. POETS A. ARNING W. BERNHARD C. ACEVEDO & H. VON DER HARDT 《European journal of clinical investigation》1997,27(4):293-298
Alveolar surfactant is well known for its ability to reduce minimal surface tension at the alveolar air–liquid interface to values below 5 mN m?1. In addition, it has been suggested that surfactant is also present in the airways, particularly in the perinatal period. We isolated surfactant from pharyngeal aspirates obtained from 33 neonates immediately after delivery and analysed it for both phospholipid (PL) composition and surface tension function. PL classes and phosphatidylcholine (PC) molecular species were determined by normal and reversed-phase high-performance liquid chromatography (HPLC), respectively. Static and dynamic surface properties of the surfactant were studied in a pulsating bubble surfactometer. Sample volume was 1.3 ± 0.5 mL (mean ± SD) with a total amount of 2.5 ± 1.3 μmol of PL and a concentration of 2.1 ± 1.0 μmol mL?1 PL. HPLC analyses of PL classes revealed a composition identical with surfactant prepared from alveolar washes, i.e. PC 83.6 ± 2.1%, sphingomyelin 1.4 ± 0.5%, phosphatidylglycerol 8.1 ± 1.6%, phosphatidylethanolamine 2.1 ± 0.5% and phosphatidylinositol 2.6 ± 1.1%. Thin-layer chromatography showed almost identical results but was more time-consuming and needed more material for analysis. Analysis of PC molecular species revealed a composition typical of human alveolar surfactant with 54.7 ± 3.9% dipalmitoyl PC, 10.3 ± 1.9% palmitoyloleoyl PC and 9.1 ± 1.5% palmitoylmyristoyl PC. Minimal surface tension fell to values below 5 mN m?1 within 5 min of cycling in all subjects. The methods used in this study allowed for complete PL and surface tension analyses of surfactant obtained during routine pharyngeal suctioning after delivery at term. Whether they are also applicable to preterm neonates with respiratory distress remains to be determined. 相似文献
6.
姚展成 《中国医师进修杂志》2003,(19)
目的 评价易善复加丹参在病毒性肝炎合并脂肪肝的临床疗效。方法 选择病毒性肝炎合并脂肪肝 98例 ,随机分成治疗组和对照组 ,治疗组 68例 ,应用易善复加丹参治疗 ,疗程 3个月。结果 治疗组血脂 (TC、TG)、肝功能 (ALT、γ -GT)、B超脂肪肝图象及临床症状等项目的改善均明显优于对照组 (P <0 .0 1~ 0 .0 5) ,且无明显副作用。结论 易善复加丹参治疗病毒性肝炎合并脂肪肝对促进肝脏脂肪代谢、降低血脂、修复损伤的肝细胞 ,且阻止或改善肝纤维化均有明显的功效 相似文献
7.
8.
The relative entry of eicosapentaenoic acid (EPA) and arachidonic acid (AA) via 1-acylglycerophosphorylcholine and 1-acylglycerophosphorylinositol acyltransferase activity into phosphatidylcholine (PC) and phosphatidylinositol (PI), respectively, was studied in human platelets. A known mixture of [14C]EPA and [3H]AA along with an acyl-CoA generating system and lyso-acceptor phospholipids were incubated with a platelet mixed membrane preparation. The radioactivities in the products were determined following lipid extraction and thin-layer chromatographic separations. The [3H]AA/[14C]EPA ratios in the products, PC and PI, indicated some preference of both acyltransferase pathways for EPA over AA at 50 μM exogenously-added lysoPC or lysoPI. Altering the concentration of lysoPC (10–50 μM) did not significantly affect the selectivity for EPA. In contrast, reducing the concentration of lysoPI from 50 μM to 10 μM changed the selectivity of the acyltransferase pathway from favouring EPA to slightly favouring AA. The presence of a mixture of lysoPC and lysoPI resulted in a partitioning of EPA more towards PC and less towards PI which may account, in some part, for the greater AA/EPA mass ratio observed in the PI from human subjects consuming fish oil. The magnitude of the differences between PC and PI in their AA/EPA mass ratios observed in vivo, however, cannot be explained by the selectivity demonstrated herein by the acyltransferase pathways. 相似文献
9.
M. Vandenbranden J.L. de Coen R. Jeener L. Kanarek J.M. Ruyschaert 《Molecular immunology》1981,18(7):621-631
Interactions between rabbit-γ-immunoglobulins and model membranes (lipid monalayers, planar lipid bilayers, liposomes) have been investigated. No significant interaction was observed with immunoglobulins. However, immunoglobulins dialysed first vs aqueous buffer having pH 2 or 3 and then dialysed against pH 7 buffer presumably adopt a new conformation which allows their bindings to model membranes. This binding is hydrophobic and the immunoglobulin region interacting with the lipid acyl chains is probably located in the heavy chain, as suggested by labelling in this region by a photosensitive probe previously incorporated into the lipid hydrophobic core. Cleavage at the hinge region by papain or pepsin, or heating above 38°C, induces the loss of the hydrophobic conformation responsible for hydrophobic bindings. The binding capacity of immunoglobulins heated above 38°C is restored after momentary dialysis at pH 2. The possible existence of two Ig isomers is discussed in relation to the mechanism of γ-immunoglobulin passage through the endoplasmic membrane and fixation into the plasma membrane. 相似文献
10.
The major phospholipids present in the phospholipid extract of Schistosoma mansoni were phosphatidylcholine (28%), phosphatidylethanolamine (25%), phosphatidylserine (15%) and phosphatidylglycerol (8%). The synthesis of phosphatidylcholine in S. mansoni adults occurred by the choline to phosphatidylcholine or Kennedy pathway. Incorporation of CDPcholine and choline into the phosphatidylcholine of worm slices appeared linear over time with no demonstrable sex differences in choline incorporation. A slight difference in the incorporation of CDPcholine by separate sexes was evident. Methylation of phosphatidylethanolamine to phosphatidylcholine could not be demonstrated. 相似文献