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1.
The retinylpalmitate-hydrolase activity in the small intestine of healthy and lambliae infected rats was determined. Infection of rats with Giardia lambliae is shown to result in a fall of the retinylpalmiate-hydrase activity, which is restored, in part, on application of a specific therapy (0.1 g/kg of chinacrine) and then practically does not differ from that in healthy animals, when the specific therapy is employed in conjunction with an elevated dose of the vitamin "A" (2000 m. u. of retinyl-palmitate per day).  相似文献   

2.
Overproduction of sebum is very common and results in an undesirable oily, shiny complexion with enlarged pores. Sebum secretion is basically under the control of 5‐α reductase, and more particularly under that of type 1 isozyme. But it is also highly sensitive to environmental factors such as temperature, humidity and food. Moreover, in Asia, the edicts of a flawless facial skin turn oily skin into a major concern for Asian women. We identified Orthosiphon stamineus leaf extract as an interesting ingredient for reducing the oily appearance of skin thanks to its ability to reduce 5‐α reductase type 1 expression in normal human epidermal keratinocytes in vitro. This was confirmed ex vivo, where Orthosiphon stamineus leaf extract was shown to reduce 5‐α reductase activity as well as the production of squalene, one of the main components of sebum that was used as a tracer of sebum. To evaluate the efficacy of Orthosiphon stamineus leaf extract at reducing sebum‐related skin imperfections in vivo, we performed two different clinical studies, one in France on a panel of Caucasian volunteers and the other one in Thailand on a panel of Asian volunteers. Using instrumental techniques as well as clinical evaluation and self‐evaluation, we could highlight that an O/W cosmetic formula containing 2% of Orthosiphon stamineus leaf extract could visibly reduce the oily appearance of skin as well as the size of pores, thus leading to a significant improvement of complexion evenness and radiance. Overall, the results obtained were better than those observed with the same formula containing 1% of zinc gluconate, an ingredient frequently used in oily skin care products.  相似文献   

3.
为明确不同产区影响上部烟叶内在品质的关键外观指标,制备我国5个生态二级区上部烟叶品质梯度样品,对不同生态区上部烟叶外观特征与感官品质、外观特征与化学成分间的相互关系进行分析。结果表明:①不同生态区上部烟叶的多数外观特征指标分值差异显著。②在一定范围内,上部烟叶随颜色加深,香气饱满程度提升,总氮含量(质量分数)增加,糖碱比值、糖含量和淀粉含量下降;随柔软度改善、油润感增强或身份趋于中等,香气质感和口感舒适程度改善,糖含量和糖碱比值升高。③随机森林特征贡献率分析发现,豫中和豫西生态区影响上部烟叶感官品质的关键外观特征指标为身份、油润感和成熟度,湘南生态区为叶片结构、身份和颜色深浅,滇东生态区为柔软度、叶片结构和颜色深浅,渝东南生态区为油润感、叶片结构和成熟度。影响上部烟叶感官品质的关键外观指标在不同生态区间存在差异。   相似文献   

4.
A representative blood sample from the mammary vein depends on the functional integrity of the valves in the external pudic vein (EPV). To determine if the EPV valves maintain blood flow into the inguinal direction during the second and subsequent lactations, we used eight lactating cows catheterized in the EPV, the lateral branch of the cranial mammary vein (MV), and the external pudic artery (EPA). The averaged daily milk yields were 25.0 +/- 1.8 kg in cows in second lactation and 31.5 +/- 2.9 kg in older cows. The relative time taken by a pulse dose of p-amino hippuric acid (PAH) injected into the EPV, to reach the EPA and the MV, was measured in a first trial. In a second trial, we assessed the extent of alteration of the mammary PAH blood concentration with blood originating from other tissues using a continuous infusion of PAH into the EPA simultaneously with blocking or not any EPV backflux. From the first experiment, the PAH injected into the EPV appeared first in the EPA and then in the MV in cows in second lactation, suggesting that blood flow was towards the inguinal region. But in a third-lactation cow, the order of appearance was reversed. In parallel, the occlusion trial demonstrated that the concentration of PAH in the MV was diluted by 14 to 39% with blood draining nonmammary tissues only in cows in third or fourth lactation. This resulting reversed flow from the EPV towards the MV would have a detrimental impact on conclusions of mammary gland metabolism studies conducted with cows in their third lactation or higher.  相似文献   

5.
Experiments on dogs with gastric fistula after Basov and Pavlov pouch demonstrated that introduction into the blood by the drip method of solutions of L-amino acids and their mixtures tends to induce gastric secretion. This effect is produced by nonessential acids somewhat more intensively than by essential ones. A complete mixture of amino acids yields the least secretory effect. Among individual amino acids under study, taken in isomolar quantities, the most intensive gastric secretion induce glycin, alanine and proline. The least active in this respect proved to be lysine.  相似文献   

6.
Recent observations on the occurrence of fishy flavour in bacon   总被引:1,自引:0,他引:1  
An examination of reject bacon samples supplied directly from a factory showed that some samples described by a sensory panel as oily and fishy contained significantly higher levels of long chain polyunsaturated fatty acids (PUFA) in their fat than normal samples. When bacon samples obtained from retail outlets were similarly analysed and then subjected to sensory assessment, those found to contain long chain PUFA were given significantly higher scores for oily and fishy flavour. Observations on the fatty acid composition of fishy bacon samples as compared to non-fishy ones and further investigation into the diets of pigs producing suspect carcasses led to the conclusion that too high a content of fish products in the diet was the main cause of the problem. Contrary to what had been believed, fresh non-fishy bacon samples did not develop fishy flavour after storage at ?20°C for 15 weeks. Perceived fishiness was not related to total copper content as determined by atomic absorption spectroscopy.  相似文献   

7.
目的 探究尾静脉注射短链酰基辅酶A脱氢酶(SCAD)重组腺病毒能否改善自发性高血压大鼠(SHR)血管重构。方法 实验分为6组:Wistar+NS组、Wistar+GFP组、Wistar+Ad-SCAD组、SHR+NS组、SHR+GFP组和SHR+Ad-SCAD组。腺病毒包装的SCAD和GFP纯化后,以尾静脉方式注射给药8周。采用超声心动图检测大鼠心功能情况;采用无创血压仪检测大鼠的血压变化;主动脉HE染色、天狼星红染色、DHE染色、TUNEL染色、EVG染色,观察血管重构。采用实时荧光定量PCR检测相关基因mRNA表达变化、Western blot检测相关蛋白表达变化,观察游离脂肪酸、一氧化氮(NO)和ATP含量变化。结果 (1)尾静脉注射SCAD重组腺病毒,大鼠主动脉中SCAD蛋白出现过表达,mRNA水平增高,SCAD酶活性增加;(2)在病理状态下,增加主动脉中SCAD表达,可以降低血压,改善心功能,改善血管管腔大小,减少胶原沉积,减少血管活性氧(ROS)的生成和细胞凋亡;(3)在病理状态下,SCAD的表达增加可减少血清和主动脉中游离脂肪酸的含量,增加组织中的ATP水平,激活内皮型一氧化氮合酶(eNOS)磷酸化,增加主动脉NO的生成。结论 自发性高血压大鼠主动脉SCAD的表达增加能逆转高血压血管重构,可能与其减少血清中游离脂肪酸的含量、增加NO水平、减少活性氧生成、消除氧化应激有关。  相似文献   

8.
目的建立电感耦合等离子体质谱法(inductively coupled plasma mass spectrometry,ICP-MS)测定烘焙纸中13种元素的方法,分析13种元素在几种模拟液中的迁移情况。方法将13种元素单标标准溶液,用4%乙酸逐级稀释,配制成不同浓度的混合标准溶液,按照选定的仪器工作条件进行上机分析,绘制标准工作曲线。对13种元素分别进行高、中、低3个浓度水平的加标回收实验,计算回收率和精密度。检测20个烘焙纸样品的13种元素含量,分别采用4%乙酸、10%乙醇和异辛烷作为迁移模拟液,在一定条件下对烘焙纸进行迁移实验,测定元素的迁移量。结果该方法线性范围为0.2~200μg/L,相关系数均>0.999、检出限0.0002~0.055mg/kg。加标回收率在82.6%~116.9%之间,相对标准偏差(relative standard deviation,RSD)1.6%~4.3%,烘焙纸中铝、钡、铜3种元素含量较高,尤其是铝元素,平均含量为559mg/kg;元素在3种迁移模拟液中迁移量的大小顺序为4%乙酸>10%乙醇>异辛烷,在4%乙酸中锂的最大迁移量可高达94.4%,在10%乙醇中迁移量最大的是钴元素,迁移量40.9%,在异辛烷中迁移量最大的是铬元素,迁移量6.9%。结论ICP-MS法测定烘焙纸中13种元素,具有线性范围宽、灵敏度高等优点,该法适用于烘焙纸等食品接触用纸中多元素的检测分析。各元素在酸性食品模拟液4%乙酸中更易迁移,在油性食品模拟液异辛烷中迁移最小,说明烘焙纸接触油脂类食品时,元素迁移的风险较低。  相似文献   

9.
Active plasticized banana flour nanocomposite film (APBNF) incorporated with a different garlic essential oil (GO) content was formed using a solution casting to determine the film properties prior to the investigation of its effectiveness to preserve the roasted peanut quality. The GO concentration was positively correlated with the ultraviolet (UV) light barrier property and antioxidant activity indicating the ability to protect the packed food product from lipid oxidation. Additionally, incorporation of 1 mg/mL GO into APBNF showed the highest antioxidant activity and completely inhibited the growth of Aspergillus flavus. Fourier-transform infrared spectroscopy confirmed the functional group interactions between the film matrix and GO which act as an antioxidant and antimicrobial agent. Thus, APBNF incorporated with 1 mg/mL GO as an active packaging to preserve the quality of roasted peanuts was investigated comparing with a commercial plastic packaging of polyethylene terephthalate/low-density polyethylene (PET/LDPE; PET). The shelf life estimation of roasted peanuts packed in both packaging materials (APBNF and PET) based on the peroxide value (PV) was similar at high storage temperature (45 °C). Therefore, APBNF shows a multifunctional primary food packaging to maintain the quality of roasted peanuts or oily food products.  相似文献   

10.
Feeding rumen-protected fat (RPF) is an alternative to increase energy density of the diet and therefore energy intake in dairy cows. To investigate metabolic and endocrine changes in dairy cows fed either a diet containing RPF (FD) or a control diet with an increased amount of cornstarch (SD), 3 Holstein cows (83 ± 1 d in milk) were fitted with catheters in the portal vein, a mesenteric artery, and 2 mesenteric veins. Cows were fed consecutively SD and FD for 3 wk, respectively. In FD, cornstarch [92 g/kg of dry matter (DM)] was replaced by 50 g of RPF/kg of DM (mainly C16:0 and C18:1). Tracer infusions of NaH13CO3 and d-[U-13C6]glucose were performed into a jugular vein to measure rate of appearance and oxidation of glucose. Arterial and portal blood samples were collected to measure concentrations of glucose, lactate, volatile fatty acids, nonesterified fatty acids, β-hydroxybutyrate, triglycerides, AA, insulin, and glucagon. Concomitantly, para-aminohippurate was infused into a mesenteric vein for measurement of portal plasma flow. Although DM intake was slightly lower in FD, protein and energy intakes were unaffected by diets. Milk and lactose yields were higher in FD than SD. Arterial plasma glucose concentration was lower with FD than SD, whereas nonesterified fatty acid and triglyceride concentrations were higher in FD. Glucagon concentration and glucagon-to-insulin ratio were both augmented by FD feeding. When feeding FD, greater milk and lactose yields, but not energy-corrected milk, were associated with elevated lipid status and higher glucagon concentrations but occurred despite lower plasma glucose concentration and were not linked with changes in whole body glucose rate of appearance. This study suggests a glucose-sparing effect allowing an enhanced lactose synthesis when feeding RPF.  相似文献   

11.
The hypocholesterolaemic effect of Cassia fistula was investigated using hypercholesterolaemic male albino rats. Hypercholesterolaemia was induced by feeding on a mixture of cholesterol plus cholic acid for a 12 weeks period. Hypercholesterolaemia was characterized by significant increase in the average levels of total lipids, total cholesterol, and triglycerides and significant decrease in phospholipids content. Administration of Cassia fistula significantly reduced blood and liver total lipids. Brain, spleen, kidneys and heart followed nearly the same trend but with moderate effect. Blood, liver, kidneys, spleen and heart total cholesterol was significantly reduced, while that of brain was not affected. The level of triglycerides was markedly improved. There was a moderate rise, however, in phospholipids content in all studied organs. That is to say a marked progress in the correction of lipid metabolism occurred. Also, administration of Cassia fistula induced a significant decrease in the high activities of serum GOT, GPT, alkaline and acid phosphatase and the values nearly returned the initial values. Total serum protein, albumin (A), globulin (G), A/G, free amino acids, uric acid and creatinine were also determined and their values were improved and attained nearly the normal values of the control group.  相似文献   

12.
This paper simulates the optics of oily coatings on textiles and proposes ways of minimising their visual perception. The simulation allows the design of formulations that incorporate oily benefit agents for fabrics with no perceptible stain marks. The prime optical factor in stain visibility is reduction in the reflection of light from the coated surface. We model the reflectivity of fabrics using the geometric model which Tsoutseos and Nobbs developed for colour appearance of textiles. We then modify this approach to deal with textiles of different thickness and coatings of different refractive indices, n. The use of Mie light scattering with an extended version of the geometric model enables us to simulate the effect of the coating microstructure on substrates. The model predicts that for thick substrates reflectivity is much less sensitive to the refractive index of the staining material compared to thinner substrates in which the loss in reflectivity is monotonous with the oil refractive index. However, beyond a threshold value of n the thicker fabrics also show a precipitous loss of reflection. The model shows that the reflectivity can be increased to make the stain invisible by modification of a fraction of the oil deposits into particulate form, by crystallisation for example. Fabric softener compositions for tumble dryer applications illustrate the model calculations.  相似文献   

13.
目的建立油豆腐中山梨酸和苯甲酸的毛细管柱气相色谱检测方法。方法在碱性条件下,样品利用硫酸锌去除基体干扰,水溶液提取,提取液经酸化后乙醚提取,浓缩后乙醇定容,用气相色谱进行分离测定。结果浓度在50~300μg/ml时,各组分线性良好(苯甲酸r=0.999 6,山梨酸r=0.999 4)。方法的相对标准偏差为1.07%~3.14%,回收率为90.6%~101.8%。结论该方法简便、快速、准确、稳定,适用于油豆腐中山梨酸和苯甲酸的检测。  相似文献   

14.
在关于芍药属油用植物研究的文献统计分析基础上,结合本课题组的已有研究成果,综述了芍药属油用植物种质资源及牡丹组的研究现状,同时为了全面汇总芍药属油用植物的研究进展,本文介绍目前研究较为有限的芍药组。主要包括芍药属油用植物种质资源简介及分布,芍药属油用植物种籽结实特性、生化成分、活性物质以及含油率,籽油主要理化指标、油脂提取工艺、脂肪酸组成、营养保健功能及所提油脂的加工利用、籽粕化学成分及功能特性。最后总结芍药属油用植物研究现状中存在的问题,并对其应用前景进行了展望。  相似文献   

15.
The content of RNA in secretory cells of the salivary glands was studied after administration of different doses of vitamin A. The experiments were carried out on 60 male albino mice weighing 20-25 g. The mice were given orally 1000, 3000, 5000 and 8000 IU of a 3.44% oily solution of retinol acetate for 10 days. The control animals received amygdalic oil. RNA content was determined by cytophotometry on a Reichert cytospectrophotometer (single-wave technique) after the sections were stained with gallocyanine-chromine alum. It was demonstrated that vitamin A given in doses that did not provoke that clinical symptoms of hypervitaminosis are capable of increasing RNA concentration in secretory cells of the salivary glands. Higher doses of the vitamin responsible for hypervitaminosis could diminish RNA concentration. In both cases vitamin A exerted a more powerful effect on secretory cells showing more intensive protein metabolism, i. e. on glandulocytes as compared to the effect on the cells of convoluted granular tubes.  相似文献   

16.
目的:制备具有较高血管紧张素转换酶(ACE)活性体外抑制率的冠突散囊菌发酵茶,并考察发酵茶液对自发性高血压大鼠(SHR)的急性降压作用。方法:考察葛根添加量、基质含水量和孢子悬浮液对ACE酶活性体外抑制率的影响,并采用正交试验进行发酵工艺优化;水提法制备发酵茶液,选择SHR模型研究发酵茶的降血压作用。结果:最优发酵工艺为20 g绿茶中添加2 g葛根量,20%基质含水量,5%孢子悬浮液接种量。与对照组相比,不同剂量的葛根降血压茶对SHR在24 h内均有降低收缩压和舒张压作用。结论:300~600 mg/kg日用剂量的葛根降血压茶的急性降压效果最显著,可在短期内降低SHR血压。  相似文献   

17.
Microfine titanium dioxide (TiO(2)) has become a frequently used physical UV filter in sunscreen formulations. Penetration of microfine TiO(2) into human skin seems to be possible because of the mean particle size of 20 nm. The small particle size results in a high surface activity of the primary particles and causes a formation of agglomerates in the formulation. The aim of this study was to investigate the in vivo and in vitro penetration behaviour of the physical UV filter into human skin. Furthermore, a stable sunscreen formulation with microfine TiO(2) which does not penetrate into the skin should be developed. According to our experiments, microfine TiO(2) penetrates deeper into human skin from an oily dispersion than from an aqueous one. Therefore, an o/w emulsion containing the dispersed micropigment in the aqueous phase was manufactured. Microfine TiO(2) cannot penetrate into human skin from this emulsion, but the storage stability of the formulation is very low at different temperatures. The encapsulation of the micropigment into liposomes does not result in a better stability but it causes a higher penetration depth of the particles into the skin.  相似文献   

18.
It was established in the experiments determining the influence of the mushroom powder on acidity of the HCl solution by means of ionometrical method that in 15 minutes after introduction 3 gram of the powder pH of the solution increases from 1.62 up to 2.64. The stable meaning of the solution pH (without fall) can be (held) the same in the presence of the powder more than 23 hours. The mushroom powder reduces the high content of the ions Pb2+ and Cu2+ in the solution from 8.8 x 10(-6) up to 3.3 x 10(-6) and from 11.8 x 10(-6) up to 8.6 x 10(-6) mole/ml correspondingly. The trustworthy reduction (fall) of the concentration of the ions Zn2+ and Cd2+ in the filtrate was not discovered (found out). To determine the content of metal in the solution the method of flaming atomic adsorption.  相似文献   

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