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91.
AIM: To evaluate the relationship between dietary diversity score (DDS) and cardiovascular risk factors in Tehranian adults. METHODS: In this population-based cross-sectional study, a representative sample of 581 subjects (295 males and 286 females) aged over 18 years, residents of Tehran, participated. Hypercholesterolaemia, hypertriglyceridaemia and low high-density lipoprotein cholesterol were defined according to the Adult Treatment Panel III guidelines of the National Cholesterol Education Program. Diabetes was defined as fasting plasma glucose concentration > or = 126 mg dl(-1) or 2-h post challenge glucose concentration > or = 200 mg dl(-1). Hypertension was defined on the basis of the sixth report of the Joint National Committee on Prevention, Detection, Evaluation and Treatment of High Blood Pressure. Dietary diversity was defined according to the Diet Quality Index revised. RESULTS: Mean (+/- standard deviation) DDS was 6.15 +/- 1.02. The probability of having diabetes (odds ratio (OR) among quartiles: 1.45, 1.26, 1.11 and 1.00, respectively; P for trend = 0.04) and hypertriglyceridaemia (OR = 1.41, 1.23, 1.05 and 1.00, respectively; P for trend=0.04) decreased with increasing quartile of the diversity score for whole grains. The probability of having obesity (OR among quartiles: 1.39, 1.06, 1.03 and 1.00, respectively; P for trend = 0.03), hypercholesterolaemia (OR = 1.46, 1.28, 1.11 and 1.00, respectively; P for trend = 0.03), hypertension (OR = 1.32, 1.17, 1.13 and 1.00, respectively; P for trend = 0.03) and high low-density lipoprotein cholesterol (LDL-C) (OR = 1.25, 1.12, 1.07 and 1.00, respectively; P for trend = 0.04) decreased with increasing quartile of the diversity score for vegetables. The probability of having hypercholesterolaemia, high LDL-C, hypertension and diabetes decreased with quartile of the DDS. But the probability of being obese increased with quartile of the DDS (P for trend = 0.03). CONCLUSION: DDS was inversely associated with cardiovascular risk factors in this cross-sectional study. Increased diversity scores of diets, to increase the variety score for vegetables, may be emphasised in programmes attempting to bring about changes in lifestyle. 相似文献
92.
OBJECTIVE: To determine the nutritional behaviour of Tehranian adolescents. SUBJECTS AND METHODS: This study was undertaken on 7669 adolescents (4070 boys and 3599 girls) of 22 junior high schools and high schools as a representative sample of Tehranian adolescents. A validated knowledge, attitudes and practices (KAP) questionnaire and a food-frequency questionnaire (FFQ) were used. Factor analysis was used to determine the key questions. RESULTS: The mean ( +/- standard deviation) age and body mass index of the adolescents was 14 +/- 1 years and 27.2 +/- 11 kg m- 2. Although 82% of girls and 75% of boys had good nutritional knowledge, only 25% of boys and 15% of girls had good nutritional practice. Eighty-five per cent of adolescents knew that drinking too many soft beverages resulted in overweight or obesity, but only 4.5% of them did not drink soft beverages. Although 89% of adolescents knew that crisps and corn balls are not healthy snacks, 45% of them used such snacks during their break time. Thirty-seven per cent of adolescents preferred whole-grain biscuits to creamy wafer ones but only 10% of adolescents used whole-grain biscuits as a snack. The most frequently consumed snacks among Tehranian adolescents were sausage sandwiches, cocoa cola, crisps and corn balls, creamy wafers, cakes, chocolate and toffee. CONCLUSION: A low percentage of Tehranian adolescents have good nutritional behaviour and in most of them their nutritional practice does not accord with their nutritional knowledge. These results indicate the necessity of nutritional intervention in Tehranian adolescents. 相似文献
93.
94.
Felled palm trunks are susceptible to fungi as long as their moisture content is above fibre saturation. During this period, palm wood has to be protected against mould and rot fungi. The study was aimed at testing environment-friendly organic acids for their protecting efficiency. Small samples of date palm (Phoenix dactylifera) and oil palm (Elaeis guineensis) wood were treated with weak organic acids and subsequently infected by moulds and wood-decay fungi. Short dipping of the samples in solutions of 5% acetic acid and propionic acid, respectively, protected all samples for two months from colonization by Aspergillus niger, Penicillium sp., Cladosporium sp. and by a natural infection. Boric acid (4%) used in practice for protection was ineffective. Decay tests with the white-rot fungus Pleurotus ostreatus, the brown-rot species Coniophora puteana and the soft-rot fungus Chaetomium globosum showed that both acids prevented most samples from fungal colonization for three weeks and reduced the decay considerably during two months. 相似文献
95.
Nasrin Nasiri Mohammad R.Marvie Mohadjer Vahid Etemad Kiomars Sefidi Leila Mohammadi Maryam Gharehaghaji 《林业研究》2018,(4)
For developing nature-based silvicultural practices in a beech forest to promote, abundance, height,vitality, and preferred growth form, regenerated trees growing in gaps were compared with those under closed canopies.A systematic 50×50 m grid was plotted in a beech stand in the Kheyrud Experimental Forest for selecting trees to measure variables in gaps and under closed canopies.Abundance and mean height of regenerated beech trees were significantly higher in closed canopies than in canopy gaps.Beech seedlings with excurrent growth were significantly taller within regeneration patches under closed canopy.Moreover, regenerated trees with high vitality were more abundant in closed canopy areas than in gaps.Thus, beech regeneration should improve under closed canopies; hence, gaps in a near natural forest should be created only after adequate regeneration and appropriate growth under the parent tree in a closed canopy area is ensured.The results of this research have profound implications for the sustainable management of the forest and for ensuring sustainable beech regeneration.The presence of a closed canopy cover likely will reduce potential stresses on oriental beech regeneration. 相似文献
96.
Nader Goodarzi Mohsen Akbari Bazm Leila Naseri Morteza Hosseinipour 《Anatomia, histologia, embryologia》2019,48(5):444-448
The Persian squirrel (Sciurus anomalus) is habitat in the Middle East countries and feed on pine acorns and other seeds. The present study was carried out to investigate the histological and volumetric features of the oesophagus in Persian squirrels. Five adult male Persian squirrels were included in the study. The cervical, thoracic and abdominal oesophagus of all subjects were processed routinely and sectioned in a serial manner. Then, the total volume of the oesophagus and its different layers were estimated using Cavalieri's principle. Histological assessment revealed a non‐keratinized stratified squamous epithelium lining the mucosa. No glands were seen in the lamina propria and submucosa. Lamina muscularis was present as a distinct layer of smooth muscle cells separating the lamina propria from the tunica submucosa. The tunica muscularis consisted of two distinct layers of striated muscle fibres: inner circular and outer longitudinal that was intermingled with few scattered smooth muscle fibres especially in the abdominal region. The thoracic region contained more amount of the lamina muscularis and tunica muscularis in comparison to the cervical or abdominal regions. The obtained results revealed that the histological structure of the Persian squirrel oesophagus has differences and similarities with other rodents and even with other species of squirrel. These findings would be useful to improve the knowledge in the areas of histological structure of the rodent digestive system. 相似文献
97.
Leila Moradkhannejhad Majid Abdouss Nasser Nikfarjam Saeedeh Mazinani Pantea Sayar 《Fibers and Polymers》2017,18(12):2349-2360
Herein, a biodegradable and biocompatible composite comprising of support membrane based on crosslinked PVA/PEG film and curcumin loaded electrospun poly(lactic acid) (PLA) nanofiber mat is introduced. The membrane film was prepared from PVA/PEG blend followed by crosslinking with an optimum amount of citric acid, 15 wt.%. After then, PLA solutions with different curcumin content, 0-11 wt.%, were electrospinned on the prepared membrane substrate. The prepared film showed high water absorption, water vapor transmission rate and superior mechanical properties with improved elastic modulus, tensile strength and with an elongation of around 320 % with respect to the non-crosslinked one. Also, the scanning electron microscopy was revealed uniformly dispersed pores throughout the membrane film with a nearly narrow in size distribution centered at 36 μm. As well, a nanostructure porous morphology was found for the electrospun fibrous curcumin loaded PLA from the scanning electron microscopy micrographs and the average fiber diameter was decreased with curcumin content. In vitro drug release from the prepared flexible composite into the vertical diffusion cell was recorded by the measuring curcuminoids content using high performance liquid chromatography and drug release kinetic evaluations were revealed that the release pattern of all prepared samples, containing different content of curcumin, well fitted to the Higuchi’s model signifying diffusion-controlled release mechanism. As well, the determined release rate at the second release stages, i.e. steady state flux (J), was varied from 0.31 to 43.53 μg·cm-2·h-1 with increasing drug content from 1 to 11 wt.%. Regarding this results, this flexible composite by providing the moist environment along with miraculous healing properties of curcumin, can be potential candidate for transdermal drug delivery. 相似文献
98.
Leila Izadi Najafabadi Alain Le-Bail Nasser Hamdami Jean-Yves Monteau Javad Keramat 《Journal of Cereal Science》2014
Bread staling involves a combination of physico-chemical phenomena that leads to a reduction of quality. This study aims at evaluating the impact of baking conditions (280 °C, 8 min; 310 °C, 5.5 min; 340 °C, 4 min), baking type (of fully baked (FB) and part-baked (PB)) and storage temperature (−18, 4 and 20 °C) on the staling of Sangak bread. Results showed that lower baking temperature with longer baking time produced drier bread with higher firmness. In FB Sangak breads, amylopectin retrogradation, amount of unfreezable water and firmness (measured by compression test) increased during storage at positive temperatures but hardness (determined by Kramer shear test) decreased significantly during first day of storage. The recrystallized amylopectin traps the free water resulting in crumb hardening. Water is also absorbed by the dry crust resulting in changes of rheological properties in the crust and crumb, and finally in staling. Storage at 4 °C resulted in increasing melting enthalpy of amylopectin crystallite in comparison with storage at 20 °C. Also it was found that firmness of PB breads due to rebaking was significantly lower than FB breads. There were no significant changes in staling parameters of FB and PB stored at −18 °C. 相似文献
99.
Leila Beigom Hejazian Banafshe Esmaeilzade Fatima Moghanni Ghoroghi Fatemeh Moradi Marzieh Beigom Hejazian Anahita Aslani Mehrdad Bakhtiari Masoud Soleimani Maliheh Nobakht 《Iranian Biomedical Journal》2012,16(4):193-201
Background
The aim of this study was to fabricate the poly caprolactone (PCL) aligned nanofiber scaffold and to evaluate the survival, adhesion, proliferation, and differentiation of rat hair follicle stem cells (HFSC) in the graft material using electrospun PCL nanofiber scaffold for tissue engineering applications.Methods
The bulge region of rat whisker was isolated and cultured in DMEM: nutrient mixture F-12 supplemented with epidermal growth factor. The morphological and biological features of cultured bulge cells were observed by light microscopy using immunocytochemistry methods. Electrospinning was used for production of PCL nanofiber scaffolds. Scanning electron microscopy (SEM), 3-(4, 5-di-methylthiazol- 2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay, and histology analysis were used to investigate the cell morphology, viability, attachment and infiltration of the HFSC on the PCL nanofiber scaffolds.Results
The results of the MTT assay showed cell viability and cell proliferation of the HFSC on PCL nanofiber scaffolds. SEM microscopy images indicated that HFSC are attached, proliferated and spread on PCL nanofiber scaffolds. Also, immunocytochemical analysis showed cell infiltration and cell differentiation on the scaffolds.Conclusion
The results of this study reveal that PCL nanofiber scaffolds are suitable for cell culture, proliferation, differentiation and attachment. Furthermore, HFSC are attached and proliferated on PCL nanofiber scaffolds.Key Words: Nanofiber, Electrospinning, Stem cells, Tissue engineering 相似文献100.
Leila ALIDOKHT Shahin OUSTAN Alireza KHATAEE Mohammad R. NEYSHABURI Adel REYHANITABAR 《土壤圈》2021,31(4):645-657
Chromium (Cr)-contaminated soils pose a great environmental risk, with high solubility and persistent leaching of Cr(VI). In this study, hydroxysulfate green rust (GRSO4), with the general formula Fe(II)4Fe(III)2(OH)12SO4·8H2O, was evaluated for its efficiency in Cr(VI) stabilization via Cr(VI) reduction to Cr(III) in four representative Cr(VI)-spiked soils. The initial concentrations of phosphate buffer-extractable Cr(VI) (Cr(VI)b) in soils 1, 2, 3, and 4 were 382.4, 575.9, 551.3, and 483.7 mg kg-1, respectively. Reduction of Cr(VI) to Cr(III) by structural Fe(II) (Fe(II)s) in GRSO4 in all studied soils was fast, wherein the application of GRSO4 markedly decreased the amount of Cr(VI)b at the Cr(VI)b/Fe(II)s stoichiometric mole ratio of 0.33. The kinetics of Cr(VI) reduction by GRSO4 could not be determined as this reaction coincided with the release of Cr(VI) from soil during the experiment. The concentration of Cr(VI)b decreased, as the Cr(VI)b/Fe(II)s ratio decreased from 0.46 to 0.20, generally to below 10 mg kg-1. Back-transformation of the generated Cr(III) was examined in the presence of manganese oxide birnessite at the birnessite/initial Cr(III) mole ratio of 4.5. The results of batch tests showed that only 5.2% of the initial Cr(III) was converted to Cr(VI) after two months, while under field capacity moisture conditions, less than 0.05% of the initial Cr(III) was oxidized to Cr(VI) after six months. The results illustrated that remediation of Cr(VI)-contaminated soils would be fast, successful, and irreversible with an appropriate quantity of fresh GRSO4. 相似文献