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91.
Landscape Ecology - Landscape ecology as an interdisciplinary science has great potential to inform landscape planning, an integrated, collaborative practice on a regional scale. It is commonly...  相似文献   
92.
Three new furostanol saponins named capsicoside E (1), capsicoside F (2), and capsicoside G (5) were obtained from the seeds of Capsicum annuum L. var. acuminatum along with known oligoglycosides (3, 4, and 6-10). On the basis of chemical and spectroscopic analyses, the structures of these new furostanol oligoglycosides were elucidated as 26-O-beta-D-glucopyranosyl-22-O-methyl-5alpha-furost-25(27)-en-2alpha,3beta,22xi,26-tetraol-3-O-beta-D-glucopyranosyl(1-->3)-beta-D-glucopyranosyl(1-->2)-[beta-D-glucopyranosyl(1-->3)]-beta-D-glucopyranosyl(1-->4)-beta-D-galactopyranoside (1), 26-O-beta-D-glucopyranosyl-(25R)-5alpha-furost-20(22)-en-2alpha,3beta,26-triol-3-O-beta-D-glucopyranosyl (1-->3)-beta-D-glucopyranosyl(1-->2)-[beta-D-glucopyranosyl(1-->3)]-beta-D-glucopyranosyl(1-->4)-beta-D-galactopyranoside (2), and 26-O-beta-D-gluco-pyranosyl-(25R)-5alpha-furosta-3beta,22xi,26-triol-3-O-beta-D-glucopyranosyl(1-->3)-beta-D-glucopyranosyl(1-->2)-[beta-D-glucopyranosyl(1-->3)]-beta-D-glucopyranosyl(1-->4)-beta-D-galactopyranoside (5). The isolated saponins showed higher antimicrobial activity against yeasts than against common fungi. Data indicated that the antiyeast activity was related to the combination of the oligosaccharide chain (S1, S2, or S3) with an O-methyl group at R(3) and the presence of a hydroxyl group at the C-2 position.  相似文献   
93.
The incidence of cardiovascular disease and endothelial dysfunction is low in the Mediterranean area, where the major proportion of daily calories comes from plant food, high in antioxidant polyphenols. It has been shown that a reduced production or enhanced inactivation of endothelium-derived nitric oxide (NO) is involved in the onset of endothelial dysfunction. We investigated the effects of Mediterranean wild plant, that is, wild artichoke and thyme, phenolic-rich extracts on NO release by porcine aortic endothelial cells (PAECs; by using indirect methods) and by cerebral cell membrane homogenates (by using direct NO detection). NO release by PAECs was significantly potentiated by 234% and 135% by wild artichoke and thyme extracts (10(-6) mol/L), respectively. Direct detection of NO release by brain membranes also showed significantly increased NO production after wild artichoke addition (+35.4%). Further, the release of another vasorelaxant factor by PAECs, that is, prostacyclin, was significantly increased by wild artichoke and thyme (10(-6) mol/L) (+269% and +190%, respectively). Investigation of the mechanism(s) of action of wild artichoke and thyme suggests maintenance of an intracellular reduced environment, as previously shown for ascorbate. Even though these data require in vivo confirmation, they suggest that regular intake of bioactive compounds from Mediterranean wild plants contributes to maintenance of proper vasomotion and to the low incidence of atherosclerosis and endothelial dysfunction recorded in the Mediterranean area.  相似文献   
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Urban green infrastructure supports resilience in cities and promotes sustainable resource management. Small green areas, including school green areas (SGAs), are an important component of urban green infrastructure, playing a key role in supplying cities with educational services. This article describes how SGAs can amplify an urban green area's connectivity and multifunctionality. The analysis was performed in Bucharest as a case study. A survey based on questionnaires was used to obtain data regarding green spaces within public schools. A total of 411 administrators from 461 public schools participated in the survey for a response rate of 89.1%. Information from the questionnaires was augmented with spatial data of SGAs and public green spaces, i.e., parks and city gardens. Using parametric and nonparametric statistical analysis, we first identified the variables that determine an SGA's presence and size. Potential connectivity assessment results showed that most of the schools that lack or have small-sized SGAs have the possibility to cover their green space deficit by developing activities within nearby public green spaces. A structural connectivity assessment of SGAs toward other public urban green areas revealed that SGAs are an important element of the urban environment by serving as stepping stones to species flow. The multifunctionality of the SGAs was emphasized through the educational services they provide, being involved in pupils’ daily activities. The increased connectivity and multifunctionality of urban green infrastructure through small, specialized green areas, such as SGAs, is an indicator of the fact that such areas can be used to ameliorate the deficit of green space in major urban areas.  相似文献   
97.
The modification of the biobased polymer chitosan is a broad and widely studied field. Herein, an insight into the hydrophobization of low-molecular-weight chitosan by substitution of amino functionalities with hexanoyl chloride is reported. Thereby, the influence of the pH of the reaction media was investigated. Further, methods for the determination of the degree of substitution based on 1H-NMR, FTIR, and potentiometric titration were compared and discussed regarding their accuracy and precision. 1H-NMR was the most accurate method, while FTIR and the potentiometric titration, though precise and reproducible, underlie the influence of complete protonation and solubility issues. Additionally, the impact of the pH variation during the synthesis on the properties of the samples was investigated by Cd2+ sorption experiments. The adjusted pH values during the synthesis and, therefore, the obtained degrees of substitution possessed a strong impact on the adsorption properties of the final material.  相似文献   
98.
The effects of transport for 5 hr by road and lairage for 48 hr on acute phase protein in Limousine feedlot beef cattle (n = 10, 14-16 months old, body weight 620 ± 70 kg) were examined. Blood was collected at before loading, immediately after unloading and 12, 24 and 48 hr after the initiation of transportation. Serum was collected for assay of haptoglobin (Hp) and serum amyloid A (SAA), plasma was obtained for assay fibrinogen (Fb) and the white blood cell count (WBC) was determined in whole blood at each time point. A significant effect of experimental conditions on Hp, SAA and WBC was observed. In particular, this effect was found 24 hr after transport for Hp and SAA and after 48 hr for WBC. Application of a linear regression model showed a high correlation between WBC and Hp and SAA. Lairage in a slaughterhouse represents a stressful condition that can compromise animal welfare and meat quality. Monitoring of SAA with the highest sensitivity and specificity could be a useful marker of welfare condition in this period.  相似文献   
99.
Changes in fruit growth rate, carbohydrate content (glucose, fructose, sucrose and starch) and enzyme activity (sucrose synthase, UDPglucose pyrophosphorylase, fructokinase, glucokinase, sucrose phosphate synthase, ADPglucose pyrophosphorylase and invertases), in the external pericarp of kiwifruit, were measured throughout the growing season. Sucrose synthase showed the highest activity among the sucrose cleaving enzymes during large part of the growing season. The activity of invertases were much lower than that of sucrose synthase until ripening started. Sucrose synthase showed a tight although not linear relationship with the fruit RGR. Furthermore, sucrose synthase showed linear and significant correlations with the activities of both fructokinase and UDPglucose pyrophosphorylase indicating a strong co-regulation of the activities of these three enzymes involved in sucrose cleavage and sink strength, in kiwifruit. Sucrose synthase is suggested to be the dominating enzyme in the cleavage of imported carbon in kiwifruit, in tight coordination with fructokinase and UDPglucose pyrophosphorylase.  相似文献   
100.
The purpose of this study was to evaluate in vitro the effects of hydrocortisone and aminophylline on adenosine diphosphate (ADP)-induced platelet aggregation in horses. Blood samples from 30 healthy Thoroughbred horses were collected by via jugular venipuncture to assess platelet aggregation. Platelet-rich and platelet-poor plasma were prepared from all samples by centrifugation and divided into three different aliquots. In the first aliquot, platelet aggregation was measured after platelet activation with 1 µM and 0.5 µM ADP (Group A). In the other two aliquots, the effect of a 10 min preincubation with hydrocortisone (Group B) or aminophylline (Group C) on ADP-induced aggregation at final ADP concentrations of 1 µM and 0.5 µM was observed. Platelet aggregation, recorded by an aggregometer, was evaluated by measuring the maximum degree of platelet aggregation and the initial velocities of platelet aggregation were obtained. Our results demonstrated the inhibitory effect of hydrocortisone and the induction effect of aminophylline on equine platelet responses in vitro.  相似文献   
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