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饮食中微量元素砷的分布规律与人体健康关系   总被引:3,自引:1,他引:2  
采用催化动力学光度法测定了六大类(共三十种)样品中的总砷含量,探讨了砷在食品中的分布规律,建立了砷在人体中的安全系效和积累系效的效学评价公式,用于评价砷与人体健康的关系,这对人们选择食物有一定的指导意义。  相似文献   
3.
Abstract

Total Diet Studies on pesticide residues in foods carried out in Italy in the last two decades are briefly summarized and data are discussed. Health risk assessment is expressed by the ratio total intake/ADI (%ADI ingested) for each compound and by the sum of the percentages of ADI for each compound within the same class of pesticides.

The total dietary intake of chlorinated pesticides, that was almost 100% of ADI in the years 1970-74, decreased down to 10% in the period 1978-84. This trend was confirmed for DDT in recent years, while data on Lindane and Heptachlor seem to be constant.

As regards the organophosphorus pesticides the sum of the percentages of ADI ingested for each compound, extrapolated from recent data (1990-1991) is about 20% and can be regarded as reasonably acceptable because the study included practically all the mainly used compounds.

Only few data are available for some pesticides like dithiocarbamates, especially EBDCs and their derivatives (e.g. ETU), other carbamates (e.g. aldicarb), paraquat etc. Moreover, analytical methods for these compounds should be improved.

The need for a considerable improvement in the number and organization of monitoring structures, in the use of standardized analytical procedures, in good laboratory practice standards and in the realibility of “monitoring protocols” and their homogeneity is evidenced.  相似文献   
4.
Betulinic acid is one such natural pentacyclic triterpenoid compound, holding various pharmacological properties but its poor bioavailability is the only limitation. One of the biological macromolecules such as Lignin is a plant-derived aromatic, eco-friendly and low-cost polymer that certainly self-assembles into nano-sized colloids. Therefore, onto the current investigation, we increased the bioavailability of betulinic acid by coating on to a nanopolymer prepared with poly vinyl alcohol, lignins and methyl acrylate. Betulinic acid loaded polyvinyl alcohol/ethylacrylate grafted Lignin polymer (PVA/Lig-g-MA) nanoformulation was characterized using FTIR, XRD, SEM and TEM analysis and also the drug entrapment, in vitro drug releasing capacity was done to examine the efficiency of the nanoformulation of a drug. The MTT assay was evaluated the cytotoxicity of synthesized nanoformulation against normal endothelial cells HUVEC and HAPEC to confirm the side effects of the drug. The anti-atherosclerotic property of the nanoformulation was ascertained in both in vitro condition (with HUVEC and HPAEC) and in vivo studies (with Wistar rats). As a result, the characterization studies and in vitro studies clearly confirmed the Betulinic acid loaded PVA/Lig-g-MA nanoformulation is an ideal nanopolymer and it doesn’t cause any cytotoxic effect in normal endothelial cells. It also decreased the lipopolysaccharides induced inflammation through the down-regulation of NFκB and MAP/JNK signaling molecule expressions. Following in vivo results confirmed the synthesized nanoformulation effectively decreased the hyperchlostremia, inflammation and vasoconstriction, which induced over high fat diet. The results of histopathological analysis of cardiac tissues also confirmed the cardioprotective role of synthesized nanoformulation. Overall, both the in vitro and in vivo studies authentically proven the Betulinic acid loaded PVA/Lig-g-MA nanoformulation would be a potent cost effective anti-atherosclerotic nanodrug.  相似文献   
5.
Changes in the nutritional status of mothers may predispose their offspring to neuromuscular disorders in the long term. This study evaluated the effects of maternal protein restriction during pregnancy and lactation on the muscle fibers and neuromuscular junctions (NMJs) of the soleus muscle in the offspring of rats at 365 days of age that had undergone nutritional recovery. Wistar rats were divided into two groups: control (CG) – the offspring of mothers fed a normal protein diet (17%) and restricted (RG) – offspring of mothers fed a low protein diet (6%). After lactation, the male pups received standard chow ad libitum. At 365 days, samples of soleus muscle were collected for muscle fiber analysis (HE staining, NADH-TR reaction and ultrastructure), intramuscular collagen quantification (picrosirius red staining) and NMJs analysis (non-specific esterase technique). The cross-sectional area of type I fibers was reduced by 20% and type IIa fibers by 5% while type IIb fibers increased by 5% in the RG compared to the CG. The percentage of intramuscular collagen was 19% lower in the RG. Disorganization of the myofibrils and Z line was observed, with the presence of clusters of mitochondria in both groups. Regarding the NMJs, in the RG there was a reduction of 10% in the area and 17% in the small diameter and an increase of 7% in the large diameter. The results indicate that the effects of maternal protein restriction on muscle fibers and NMJs seem to be long-lasting and irreversible.  相似文献   
6.
Abstract

Breakfast habits affect the nutritional status and health of people, in particular children and adolescents. This is the second part a previous study about the adherence to the Mediterranean diet in a Sicilian (Italy) student population. The investigation analysed both normal weight and overweight subjects in order to understand how eating habits, number of meals and daily calorie intakes could affect their body mass indexes (BMI). The aim of this second part was to analyse the breakfast nutritional profiles of this student population. The results highlighted that breakfast was regularly consumed by a percentage ranging from a maximum of 84% (in normal subjects) to a minimum value of 57.4% (in overweight/obese students). Milk, yoghurt, sugar, bread/rusk and tea contributed as main foods to the breakfast composition. The results highlighted that subjects who consumed breakfast showed lower BMI values with significant differences between normal and overweight/obese students.  相似文献   
7.
Obesity is a foremost health issue that affects about 1.6 million people out of which 400 million worldwide. Epidemiological evidences prove obesity is the primary cause for various metabolic ailments e.g. diabetes. Poria cocos possess extensive biological actions, for instance, antioxidant, anti-inflammatory, antitumor, immunomodulatory actions. The primary limitation of all phytomedicine was their poor bioavailability hence in this investigation, we bio-fabricated the gold nanoparticles from Poria cocos aqueous extract and inspected their potency to treat obesity. Obese rat model were produced via fed the young female rats with high fat food for 8 weeks regimen. Further to confirm the potency of Poria cocos gold nanoparticles against obesity induced metabolic disorders we treated obese rats with low dose streptozotocin in the conclusion of the investigational time. The synthesis of Poria cocos gold-nanoparticles was evidenced via the UV-Spectroscopic study and characterized with SEM, TEM and EDAX studies. The anti-obesity actions of Poria cocos gold-nanoparticles were investigated by estimating the glucose profile, kidney markers, lipid profile, inflammatory cytokines, adipocyte markers, antioxidants in the Poria cocos gold nanoparticles treated obese rats. To confirm the Poria cocos gold nanoparticles role on inhibiting the obesity induced metabolic disorders we analyzed the histopathological changes in cardiac tissues. Our physical characterization confirms the synthesized Poria cocos gold nanoparticles assure the distinctions of influential nanoparticles to be utilized for the treatment. The results from biochemical and histopathological analysis confirms Poria cocos gold nanoparticles is a persuasive antidiabetic, anti-inflammatory, antioxidant, anti-obesity drug. Overall our results authentically confirm Poria cocos gold nanoparticles is a potent anti-obesity drug and it also protects from obesity induced metabolic disorders.  相似文献   
8.
There is currently a worldwide consensus and recognition of the undoubted health benefits of the so-called Mediterranean diet, with its intake being associated with a lower risk of mortality. The most important characteristics of this type of diet are based on the consumption of significant amounts of fruit, vegetables, legumes, and nuts, which provide, in addition to some active ingredients, fiber and a proportion of vegetable protein, together with extra virgin olive oil (EVOO) as the main sources of vegetable fat. Fish and meat from poultry and other small farm animals are the main sources of protein. One of the main components, as already mentioned, is EVOO, which is rich in monounsaturated fatty acids and to a lesser extent in polyunsaturated fatty acids. The intake of this type of nutrient also provides an important set of phytochemicals whose health potential is widely spread and agreed upon. These phytochemicals include significant amounts of anthocyanins, stilbenes, flavonoids, phenolic acids, and terpenes of varying complexities. Therefore, the inclusion in the diet of this type of molecules, with a proven healthy effect, provides an unquestionable preventive and/or curative activity on an important group of pathologies related to cardiovascular, infectious, and cancerous diseases, as well as those related to the metabolic syndrome. The aim of this review is therefore to shed light on the nutraceutical role of two of the main phytochemicals present in Olea europaea fruit and leaf extracts, polyphenols, and triterpenes, on healthy animal growth. Their immunomodulatory, anti-infective, antioxidant, anti-aging, and anti-carcinogenic capabilities show them to be potential nutraceuticals, providing healthy growth.  相似文献   
9.
人体微量元素平衡与健康饮食   总被引:4,自引:0,他引:4  
综述了人体微量元素平衡与健康饮食的关系。微量元素参与机体内的各种代谢,在维持人的生命活动中发挥着重要的作用。正确理解微量元素的生理功能,树立科学的平衡营养观,是引导人们自觉地实现多样化饮食、促进健康长寿的关键。  相似文献   
10.
The purpose of this study was to investigate the effect of radiation on the content of animal diet constituents using global metabolomics. Aqueous methanolic extracts of control and cobalt‐60‐irradiated Teklad 7001 diets were comprehensively analyzed using nano‐liquid chromatography–MS/MS. Among the over 2000 ions revealed by XCMS followed by data preprocessing, 94 positive and 143 negative metabolite ions had greater than 1.5‐fold changes and p‐values <0.01. Use of MetaboAnalyst statistical software demonstrated complete separation of the irradiated and non‐radiated diets in unsupervised principal components analysis and supervised partial least squares discriminant analysis. Irradiation led to an increase in the content of phytochemicals such as glucosinolates and oxidized lipids in the diet. Twenty‐eight metabolites that were significantly changed in the irradiated samples were putatively identified at the level of molecular formulae by MS/MS. MS/MSALL analysis of chloroform–methanol extracts of the irradiated diet showed increased levels of a number of unique linoleic acid‐derived branched fatty acid esters of hydroxy fatty acids. These data imply that gamma irradiation of animal diets causes chemical changes to dietary components, which in turn may influence the risk of mammary cancer. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
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