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141.
142.
González-Sarrías A Gromek S Niesen D Seeram NP Henry GE 《Journal of agricultural and food chemistry》2011,59(16):8632-8638
Research has shown that members of the Carex genus produce biologically active stilbenoids including resveratrol oligomers. This is of great interest to the nutraceutical industry given that resveratrol, a constituent of grape and red wine, has attracted immense research attention due to its potential human health benefits. In the current study, five resveratrol oligomers (isolated from Carex folliculata and Carex gynandra ), along with resveratrol, were evaluated for antiproliferative effects against human colon cancer (HCT-116, HT-29, Caco-2) and normal human colon (CCD-18Co) cells. The resveratrol oligomers included one dimer, two trimers, and two tetramers: pallidol (1); α-viniferin (2) and trans-miyabenol C (3); and kobophenols A (4) and B (5), respectively. Although not cytotoxic, the resveratrol oligomers (1-5), as well as resveratrol, inhibited growth of the human colon cancer cells. Among the six stilbenoids, α-viniferin (2) was most active against the colon cancer cells with IC(50) values of 6-32 μM (>2-fold compared to normal colon cells). Moreover, α-viniferin (at 20 μM) did not induce apoptosis but arrested cell cycle (in the S-phase) for the colon cancer but not the normal colon cells. This study adds to the growing body of knowledge supporting the anticancer effects of resveratrol and its oligomers. Furthermore, Carex species should be investigated for their nutraceutical potential given that they produce biologically active stilbenoids such as α-viniferin. 相似文献
143.
Orobanche amethystea Thuill.,O. loricata Reichenb. andO. pubescens D’Urv. were found to parasitize the roots of cultivated plants in Israel.Orobanche pubescens is known from the local flora, and was now found to cause damage in parsley fields and toTropaeolum majus L. (nasturtium) in ornamental gardens.Orobanche amethystea andO. loricata are known as occasional weeds in Europe and were recently found for the first time in Israel.Orobanche amethystea densely populated vetch fields in Israel, andO. loricata was found in ornamental gardens. A key for the identification ofOrobanche species in cultivated areas in Israel is given, based on morphological features.
http://www.phytoparasitica.org posting Jan. 13, 2002. 相似文献
144.
John M. MacGregor John E. Rush Nancy J. Laste Rebecca L. Malakoff Suzanne M. Cunningham Natalie Aronow Daniel J. Hall Justin Williams Lori L. Price 《Journal of Veterinary Cardiology》2011,13(4):251-260
Hypothesis/ObjectivesTo describe the therapeutic use of pimobendan in cats, describe the patient population to which it was administered, document potential side effects and report the clinical course following administration of pimobendan in conjunction with standard heart failure therapy. It is hypothesized that cats with advanced heart disease including congestive heart failure from a variety of causes will tolerate pimobendan with a minimum of side effects when used in treatment in conjunction with a variety of other medications.Animals, materials and methodsOne hundred and seventy client owned cats with naturally occurring heart disease, one hundred and sixty four of which had congestive heart failure. Medical records were reviewed and owners and referring veterinarians were contacted for follow-up data. Data collected included pimobendan dose, other medications administered concurrently, data collected at physical examination, presence or absence of heart failure, adverse effects, classification of heart disease, echocardiographic data and survival time. The data were analyzed for significance between the initial visit and any follow-up visits.ResultsAll cats were treated with pimobendan. The median pimobendan dose was 0.24 mg/kg q 12 h. Pimobendan was used in combination with multiple concurrent medications including angiotensin converting enzyme inhibitors, diuretics and anti-thrombotics. Five cats (3.0%) had potential side effects associated with pimobendan. One cat (0.6%) had presumed side effects severe enough to discontinue pimobendan use. Median survival time for 164 cats with congestive heart failure after initiation of pimobendan was 151 days (range 1–870).ConclusionPimobendan appears to be well tolerated in cats with advanced heart disease when used with a variety of concurrent medications. Randomized controlled studies need to be performed to accurately assess whether it is efficacious for treatment of congestive heart failure in cats. 相似文献
145.
Nicolas Marron Cécilia Gana Dominique Gérant Pascale Maillard Pierrick Priault Daniel Epron 《植物养料与土壤学杂志》2018,181(2):296-304
Estimating symbiotic di‐nitrogen (N2) fixation is challenging, especially when working with woody N2 fixers in field trials. Fortunately, isotope methods based on 15N natural abundance or on 15N artificial enrichment (dilution method) make it possible to estimate the proportion of nitrogen derived from the atmosphere (Ndfa) in N2‐fixing species. These methods have been extensively used in the field for herbaceous species, much less for tree species such as alder and acacia, and rarely for black locust (Robinia pseudoacacia). The objectives of this study were to characterize the fixation potential of black locust in a plantation by using the two 15N isotope methods in the field, and to document values of isotope fractionation occurring during N2 fixation (the B value). B values were estimated both by growing trees on an N‐free medium in controlled conditions (Blab) and by making Ndfa calculated with the natural abundance method converge with Ndfa calculated with the 15N dilution method in the field (Bfield). The two methods gave consistent estimates of the B value. B values ranging between –1.4 and –3.2‰ were found, varying with the age of the plant material. Up to 76% of the N in the black locust trees came from the atmosphere, representing more than 45 kg N ha?1 over five years and confirming that black locust may be well adapted to N‐poor soils. 相似文献
146.
Daniel Kohl C. von Boyneburgk M. Feldmann H.-P. Heim S. Böhm 《Wood material science & engineering》2020,15(3):130-139
ABSTRACTDue to its naturally grown properties, wood has played a rather subordinate role as a material for technical applications up to now. In this paper, multi-material systems based on veneers of beech (Fagus sylvatica) with different reinforcing variants were investigated. In addition to the influence of different adhesive systems (urea formaldehyde and polyurethane), the effect of reinforcing by aramid fiber fabric and stainless steel foil in different climates was examined. At the center of the investigations were dynamically sudden loads, in the form of impact bending and dart drop tests (penetration and impact mode). It has been shown that the use of the reinforcing materials leads to a significant improvement in material properties. The penetration energy of the composites reinforced with the aramid fiber fabric could be increased by 43%. The maximum force in the dart drop test (impact mode) could be increased by 29% with the stainless steel foil, the damping decreased by 48%. The aramid fiber reinforcement achieved an increase in impact resistance by 27% in impact bending test, the steel reinforced achieved an increase of 39%. A clear dependency on both, the climate and the adhesive within the composite, could be demonstrated. 相似文献
147.
Impacts of resource extraction on forest structure and diversity in Bardia National Park,Nepal 总被引:1,自引:0,他引:1
Repeated biomass harvesting for human livelihood needs can cause significant changes in forest structure, composition and diversity. Such impacts have often been associated with the distance to villages and their size, but the effects of individual villages in relation to their characteristics have been little studied. Focussing on the issues around communities’ impacts on the forest, this research aimed to understand how resource extraction by two Buffer Zone villages in Nepal's Bardia National Park affects forest structure and diversity. Tree density, basal area, diameter at breast height (DBH), species richness, two diversity indices and disturbance indices were recorded in 108 plots in 12 transects, from March till May 2005, within the park along the village boundaries, where resource extraction occurs, and in the core park area which is isolated from human disturbance. Forest subject to resource extraction had a lower density of trees, smaller DBH and lower species richness and diversity. Forest disturbance declined with distance from the villages but the two villages differed widely in their impact on the forest. Resource use was more intensive in Shivapur village and percentage of trees lopped, average lopping intensity and numbers of dung piles were statistically significant. This was mainly due to the lack of access to Buffer Zone community Forest for Shivapur households. Interviews with villagers suggested that there have been changes in species availability compared to 5 years ago. Households also underestimated the impact of their resource extraction, which may prevent them from changing their behaviour to benefit conservation. It is clear that understanding rural communities’ needs, their framing of resource extraction and utilisation, and dependence on forest resources will be very helpful for long term conservation measures. 相似文献
148.
149.
Daniel W. Gladish Daniel E. Pagendam Luk J. M. Peeters Petra M. Kuhnert Jai Vaze 《Journal of Agricultural, Biological & Environmental Statistics》2018,23(1):39-62
Complex, mechanistic hydrological models can be computationally expensive, have large numbers of input parameters, and generate multivariate output. Model emulators can be constructed to approximate these complex models with substantial computational savings, making activities such as sensitivity analysis, calibration and uncertainty analysis feasible. Success in the use of an emulator relies on it making accurate and precise predictions of the model output. However, it is often unclear what type of emulation approach will be suitable. We present a comparison of reduced-rank, multivariate emulators built upon different ‘emulation engines’ and apply them to the Australian Water Resource Assessment System model. We examine first-order and second-order approaches which focus on specifying the mean and covariance, respectively. We also introduce a nonparametric approach for quantifying the uncertainty associated with the emulated prediction where this has bounded support. Our results demonstrate that emulation engines based on second-order approaches, such as Gaussian processes, can be computationally burdensome and may be comparable in performance to computationally efficient, first-order methods such as random forests.Supplementary materials accompanying this paper appear online. 相似文献
150.
Robert C Cole Federica Morandi James Avenell Gregory B Daniel 《Veterinary radiology & ultrasound》2005,46(2):146-152
The purpose of this study was to (1) establish a technique for ultrasound-guided trans-splenic portal scintigraphy (TSPS) using 99mTcO4(-), (2) evaluate portal vein morphology, (3) compare the radiation exposures for TSPS vs. per-rectal portal scintigraphy (PRPS), and (4) compare the quality of numerical data from the TSPS vs. PRPS. Eight juvenile dogs underwent PRPS and TSPS (minimum of 48h between studies) after initial screening tests. PRPS was done according to established protocol using 425 +/- 36MBq (mean +/- SD) of 99mTcO4(-). TSPS was done with the dogs in right lateral recumbency over the gamma camera. 99mTcO4(-) (57 +/- 13.9 MBq) was injected into the spleen 1-2s following initiation of the dynamic acquisition. The frame rate was 4 frames/s for 5 min. There was significantly lower radioactivity of 99mTcO4(-) given and significantly higher total counts recorded in the liver and heart during the TSPS compared with PRPS. The total counts for the TSPS and PRPS were 7120 +/- 4386 and 830 +/- 523, respectively. Percent absorption from the spleen was 52.5 +/- 19.1% compared with 9.2 +/- 5.7% for the colon. Calculated transit time for the TSPS studies was 7 +/- 2.3s. In TSPS studies, the splenic and portal veins were clearly identified. Radiation exposure levels of the dogs were significantly lower following TSPS than after PRPS. TSPS appears superior to PRPS as a method to image the portal venous system representing a valid alternative diagnostic test for animals with suspected portosystemic shunts. 相似文献