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排序方式: 共有73条查询结果,搜索用时 15 毫秒
31.
Yu W Jia L Wang P Lawson KA Simmons-Menchaca M Park SK Sun L Sanders BG Kline K 《Molecular nutrition & food research》2008,52(4):447-456
The goal of these studies was to investigate the potential anticancer properties of two naturally occurring plant sources and two manufactured synthetic forms of vitamin E, i. e., RRR-alpha-tocopherol (alphaT), RRR-gamma-tocopherol (gammaT), all-rac-alpha-tocopherol (all-rac-alphaT), and all-rac-alpha-tocopheryl acetate (all-rac-alphaTAc) in breast cancer models. Vitamin E compounds were evaluated in vitro for inhibition of colony formation and induction of apoptosis in human MDA-MB-435 and MCF-7 breast cancer cells and murine 66cl-4 mammary cancer cells and in vivo for ability to reduce tumor growth and lung and lymph node metastases using the transplantable syngeneic BALB/c mouse 66cl-4-GFP mammary cancer model. gammaT inhibited colony formation and induced apoptosis in all three cancer cell lines. alphaT and all-rac-alphaT were less effective and all-rac-alphaTAc was ineffective. gammaT-induced apoptosis was correlated with activation of caspases-8 and -9 and down-regulation of protein expression of c-FLIP and survivin. In vivo study 1 analyses showed that all-rac-alphaT and all-rac-alphaTAc significantly inhibited tumor growth and inhibited both visible and microscopic size lung metastases. In vivo study 2 analyses showed that alphaT and gammaT reduced tumor growth, but only gammaT reduced tumor growth significantly in comparison to control. In conclusion, synthetic, but not natural, vitamin E exhibits promising anti-cancer properties in vivo. 相似文献
32.
The study was constructed to monitor representative inflow and outflow from infiltration and non-infiltration type best management practice (BMP) sites developed at a university campus, allowing the determination of overall performance efficiency in terms of runoff reduction and pollutant removal. Based on the monitored storm events, the runoff and discharged volume and flow rates exhibited high positive correlations with total rainfall depth (p<0.001). Findings revealed that as the total rainfall increases, the amount of volume reduction and pollutant removal decreases for both types of BMP. Infiltration BMP showed a higher ability in treatment performance especially during small storm events than non-infiltration type; however, the differences were not significant. Pollutant removal rates of infiltration type were in the range of 70-90% while between 35 and 80% for the non-infiltration type for storm events with less than 10 mm rainfall depth. Average volume reductions were 71 ± 33% and 32 ± 32% for the infiltration and non-infiltration type, respectively. The ratio of the discharge volume was significantly greater than the ratio of discharge pollutant load indicating a high potential for water quality improvement. Design recommendations were provided considering sizing and cost for on-site application of similar BMP designs in the future. 相似文献
33.
A high-energy laser attenuator in the range of 250 mJ (20 ns pulse width, 10 Hz repetition rate, 1064 nm wavelength) is described. The optical elements that constitute the attenuator are mirrors with relatively low reflectance, oriented at a 45 degrees angle of incidence. By combining three pairs of mirrors, the incoming radiation is collinear and has the same polarization orientation as the exit. We present damage testing and polarization-dependent reflectance measurements for 1064 nm laser light at 45 degrees angle of incidence for molybdenum, silicon carbide, and copper mirrors. A six element, 74 times (18 dB) attenuator is presented as an example. 相似文献
34.
John Parry Zhigang Hao Marla Luther Lan Su Kequan Zhou Liangli Yu 《Journal of the American Oil Chemists' Society》2006,83(10):847-854
Cold-pressed onion, parsley, cardamom, mullein, roasted pumpkin, and milk thistle seed oils were characterized for their fatty
acid (FA) composition, tocopherol content, carotenoid profile, total phenolic content (TPC), oxidative stability index (OSI),
color, physical properties, and radical-scavenging capacities against peroxyl (oxygen radical-scavenging capacity) and stable
DPPH (diphenylpicrylhydrazyl) radicals. Parsley seed oil had the highest oleic acid content, 81 g/100 g total FA, and the
lowest saturated fat among the tested oils. Roasted pumpkin seed oil contained the highest level of total carotenoids, zeaxanthin,
β-carotene, cryptoxanthin, and lutein at 71 μmol/kg and 28.5, 6.0, 4.9, and 0.3 mg/kg oil, respectively. Onion seed oil exhibited
the highest levels of α- and total tocopherols under the experimental conditions. One of the parsley seed oils exhibited the
strongest DPPH scavenging capacity and the highest oxygen radical absorbance capacity (ORAC) value of 1098 μmol Trolox equiv/g
oil. However, ORAC values of the tested seed oils were not necessarily correlated to their DPPH scavenging capacities under
the experimental conditions. The highest TPC of 3.4 mg gallic acid equiv/g oil was detected in one of the onion seed oils.
The OSI values were 13.3, 16.9–31.4, 47.8, and 61.7 h for the milk thistle, onion, mullein, and roasted pumpkin seed oils,
respectively. These data suggest that these seed oils may serve as dietary sources of special FA, tocopherols, carotenoids,
phenolic compounds, and natural antioxidants.
An erratum to this article is available at . 相似文献
35.
The absorption of equivalent doses of eicosapentaenoic and docosahexaenoic acids was compared in rats when administered as
the ethyl ester concentrate, ethyl ester concentrate plus olive oil, free fatty acid or triacylglycerol (menhaden oil). Lymph
was collected from a thoracic duct cannula for 24 hr after dosing via an indwelling duodenal catheter. After 24 hr, the absorption
of eicosapentaenoic acid was greater for the free fatty acid and menhaden oil than for the ethyl ester form, but docosahexaenoic
acid absorption was comparable for all forms. Other rats had greater plasma levels of eicosapentaenoic and docosahexaenoic
acids 5 hr after oral gavage dosing with menhaden oil than did rats dosed with the ethyl ester form. 相似文献
36.
Marla Karolyne dos Santos Horta Francisco José Moura Marilza Sampaio Aguilar Cecília Buzatto Westin Daniel Navarro da Rocha José Brant de Campos 《International Journal of Applied Ceramic Technology》2021,18(6):1930-1937
This study reports the obtainment of bioactive hydroxyapatite (HAp) extracted from scales of arowana fish (FSHA) (Osteoglossum bicirrhosum) by alkaline treatment followed by calcination at 600 and 800°C. The cell viability and bioactivity of hydroxyapatite particles (FSHA) were investigated and compared with those of HAp synthesized (s.HA) by the precipitation method. The HAp particles from fish scales showed non-toxic behavior to dental pulp stem cells similar to HAp synthesized. Additionally, bioactivity assays show that the Hap from natural source forms the bone-like apatite layer faster than s.HA sample, after being incubated in McCoy medium for 3 days. The results illustrate that HAp obtained from Osteoglossum bicirrhosum fish scale bio-waste showed excellent biocompatibility. Besides, this study provides an effective method for converting low-cost bio-waste into a value-added and it can be a potential alternative biomaterial for various biomedical applications. 相似文献
37.
Odorants that Induce Hygienic Behavior in Honeybees: Identification of Volatile Compounds in Chalkbrood-Infected Honeybee Larvae 总被引:3,自引:0,他引:3
Jodi A. I. Swanson Baldwyn Torto Stephen A. Kells Karen A. Mesce James H. Tumlinson Marla Spivak 《Journal of chemical ecology》2009,35(9):1108-1116
Social insects that live in large colonies are vulnerable to disease transmission due to relatively high genetic relatedness
among individuals and high rates of contact within and across generations. While individual insects rely on innate immune
responses, groups of individuals also have evolved social immunity. Hygienic behavior, in which individual honeybees detect
chemical stimuli from diseased larvae and subsequently remove the diseased brood from the nest, is one type of social immunity
that reduces pathogen transmission. Three volatile compounds, collected from larvae infected with the fungal pathogen Ascosphaera apis and detected by adult honey bees, were identified by coupled gas chromatography-electroantennographic detection and gas chromatography-mass
spectrometry. These three compounds, phenethyl acetate, 2-phenylethanol, and benzyl alcohol, were present in volatile collections
from infected larvae but were absent from collections from healthy larvae. Two field bioassays revealed that one of the compounds,
phenethyl acetate is a key compound associated with Ascosphaera apis-infected larvae that induces hygienic behavior. 相似文献
38.
Marla Nelson 《Journal of the American Planning Association. American Planning Association》2014,80(4):426-437
Problem, research strategy, and findings: Although many researchers frame post-disaster reconstruction as an opportunity to build safer communities less vulnerable to natural hazards, widespread land use change and relocations are rare in the United States. Residents often resist relocation and attempt to recreate the city as it was before the disaster. In this study, I examine the potential of land swaps to encourage post-disaster redevelopment that is more concentrated and less vulnerable to hazards, while expanding resettlement options for displaced residents. This article is based on a case study of an innovative land swap program developed in New Orleans after Hurricane Katrina by a nonprofit housing organization, Project Home Again (PHA). PHA's land swap program concentrated redevelopment during a time of uncertain population return and expanded resettlement options for nearly 100 low- and moderate-income households devastated by Hurricane Katrina's floodwaters. I describe the operation of PHA's land swap program and identify three conditions that can increase the viability and impact of land swaps in other disaster recovery settings: the incorporation of land swaps into housing recovery policy; cross-sector collaboration in the implementation of land swaps; and coordination with public or quasi-public land banks.Takeaway for practice: Land swaps can be a useful tool in disaster recovery by helping to guide redevelopment while expanding resettlement options for displaced residents. Increasing the range of relocation and resettlement tools available to planners is essential as repeated extreme weather events, sea level rise, and coastal erosion threaten the habitability of more and more cities and communities. 相似文献
39.
Examined the relative contributions of visual and nonvisual sensory information to place navigation performance. In Exp 1, 48 undergraduates walked without vision to a target location they had either previously viewed, were led to and from blindfolded, or both viewed and were led to and from blindfolded. In Exp 2, 24 undergraduates estimated the distance of a target they either viewed or were led to blindfolded. When vision was available, men overestimated target distance and women underestimated it. A course to the target could be set and held without vision only if prior vision of its location was available. The locomotor group reproduced the heading and distance to the target less accurately than the other groups, which did not differ significantly. However, when nonvisual information accompanied vision of the target location, it served to subtly influence performance. When target distance was learned nonvisually, no sex differences in distance estimations emerged. The findings suggest that deriving navigation information from nonvisual locomotion is difficult and may be dependent on prior visual information. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
40.
Belay Hiwote; Burton Christie L.; Lovic Vedran; Meaney Michael J.; Sokolowski Marla; Fleming Alison S. 《Canadian Metallurgical Quarterly》2011,125(2):150
Despite its importance for development, relatively little is known about how allelic variation interacts with both pre- and postnatal stress. We examined the interaction between serotonin transporter (5-HTT) genotype, prenatal and postnatal stress on glucocorticoid receptor (GR) mRNA expression, corticosteroid stress responses, and behavior in adult male rats. Prenatal stress involved a daily restraint of pregnant dams from gestational Day 10–21. Postnatal stress involved raising pups after parturition either by their mothers (MR) or in the artificial rearing (AR) paradigm, with or without additional “licking-like” stroking stimulation. 5-HTT genotype, hippocampal GR mRNA level, corticosteroid stress response, and behaviors including startle response, prepulse inhibition (PPI), and locomotor activity were measured in adult male rat offspring. We found significant genotype by prenatal stress interactions for hippocampal GR mRNA levels and for the corticosterone stress responses in adulthood. In contrast, behavioral endpoints tended to be more clearly affected by an interaction between genotype and postnatal environment. These findings suggest that allelic variation in the 5-HTT gene interacts with the prenatal environment to affect the hypothalamic-pituitary-adrenal (HPA) axis physiology and the postnatal environment to affect behavior. These results are the first to indicate a role for genetic variation in the 5-HTT gene in physiology and behavior in the rat. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献