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Summary A modified solute exclusion technique was used to pressure impregnate a polystyrene molecular weight (MW) series dissolved in styrene into red maple samples at approximately the fiber saturation point (FSP) and oven dry (OD). Radial penetration was less than tangential and FSP less than OD. There was a marked change in radial OD penetration at 900,000 MW. There was no marked penetration change with MW in the tangential direction, although there appeared to be a slight decrease in FSP penetration at the higher MW tested.  相似文献   
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INTRODUCTION: Oxidation of low density lipoprotein (LDL) has been strongly implicated in the phathogenesis of atherosclerosis. The use of oxidants in dietary food stuff may lead to the production of oxidized LDL and may increase both the development and the progression of atherosclerosis. The present work investigated the effects of some elements including: copper (Cu), iron (Fe), vanadium (V) and titanium (Ti) on in vitro LDL oxidation quantitatively. METHODS: The first LDL fraction was isolated from fresh plasma by single vertical discontinuous density gradient ultracentrifugation. The formation of conjugated dienes and thiobarbituric acid reactive substances and increase in electrophoretic mobility of LDL were monitored as markers of the oxidation of LDL. RESULTS: It was demonstrated that Cu, Fe, V and Ti exhibited strong oxidant activity in this respect (P<0.001). Oxidation of LDL in the presence of Cu was more and appeared to be in this order Cu>Fe>V>Ti. DISCUSSION: Cu, Fe, V and Ti are redox-active transition metals that may cause oxidative damage to lipids, proteins and DNA molecules. We suggest that these elements may also influence the oxidation of LDL in vivo, which could increase both the development and progression of atherosclerosis.  相似文献   
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Aim

This review focuses on plants currently used and those with a high potency for the future development of anti-acne products.

Methods

All relevant literature databases were searched up to 25 March 2011. The search terms were plant, herb, herbal therapy, phytotherapy, and acne, acne vulgaris and anti-acne. All of the human, animal, and in vitro studies, and reviews were included. Anti-bacterial, anti-inflammatory, anti-oxidant, and anti-androgen effects were the key outcomes.

Results

Studies on cell lines revealed that flavonoid, alkaloid, essential oil, phenol and phenolic compound, tannin, xanthone and xanthone derivative, and the bisnaphthquione derivative are effective in treatment of acne. Animal studies showed that diterpene acid, phenylpropanoid glycosides, acteoside and flavonoids have anti-inflammatory activity. Eleven human studies revealed that Camellia sinensis has 5α-reductase inhibitory and anti-inflammatory activities. Also anti-bacterial effect was shown by oleoresin of Commiphora mukul.

Conclusion

In addition to the standardization of these herbs, screening herbs as anti-acne agents may help to find new sources of therapy for acne.  相似文献   
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Journal of Plant Diseases and Protection - Beet black scorch virus (BBSV) was surveyed in major sugar beet cultivation areas in Iran in 2008–2013 growing seasons. A total of 148 out of 308...  相似文献   
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This paper examines the changes in the population ecology parameters and biomass of golden grey mullet (Liza aurata) in Iranian waters of the Caspian Sea from 1991 to 2005. For most years during this 14-year period, we estimated the age structure of the catch, length–weight relationship, von Bertalanffy growth parameters, condition factor, natural and fishing mortality and biomass. Growth parameters were estimated as L = 62.7 cm, K = 0.15 year−1, t0 = −0.23 year−1. The instantaneous coefficient of natural mortality was estimated as 0.350 year−1 and the instantaneous coefficient of fishing mortality varied during the 14-year period between 0.111 to 0.539 year−1. Biomass estimates of golden grey mullet, from the biomass-based cohort analysis were increased from 13,527 mt in 1991–1992 to 23,992 mt in 2002–2003. In 2004–2005, it was estimated to be 23,658 mt. We concluded that at the present time, the stock of golden grey mullet is not being over-fished.  相似文献   
37.
The interactive influences of water quality and surge-flow irrigation (intermittent application of water) on infiltration into a bare loam soil, packed into a long metal flume, were measured with a laboratory recirculating infiltrometer devised for the experiments. Cumulative infiltration and final infiltration rates were measured over three irrigation episodes using synthetic waters of different qualities. Four water-quality combinations of low and high salinity levels (i.e., electrical conductivity, EC=1.5 and 7.5 dS/m) and low and high degree of sodicity [i.e., sodium adsorption ratio in the range of 5-10 and 25-35 mmol1/2 l-1/2] were tested. Results showed that surge-flow cumulative infiltration of low saline waters - especially during the first irrigation episode - was lower than the corresponding continuous-flow cumulative infiltration. Conversely, it was higher for high saline and high saline-sodic waters. Effects of the water-quality treatments on final infiltration rate were similar to and in agreement with the effects on cumulative infiltration. However, the range of the final infiltration rates among surge-flow treatments was larger than with the continuous-flow treatments. Overall, infiltration was higher with surge-flow application of high saline and high saline-sodic waters than with the continuous-flow treatment. The observed contrasting results for the surge effect with the low saline, high saline, and high saline-sodic water-quality treatments were attributed to soil consolidation, formation of a depositional seal layer, and the different levels of irrigation water salinity and sodicity. It was concluded that the "surge effect" phenomena (reduction in soil infiltration caused by surge flow) under brackish (saline, sodic, and saline-sodic) water application was not pronounced and had adverse effects, in comparison to the low saline-sodic water application. Consequently, from theory, practical application of surge-flow irrigation under these circumstances, from viewpoints of infiltration reduction and irrigation efficiency improvements, is questionable.  相似文献   
38.
Data have been collected from slaughterhouses in three provinces across the Northern Iran (Gilan, Mazandaran and Golestan) from March 2004 to March 2008. These data were collected to evaluate the prevalence of hydatidosis in slaughtered cattle, sheep and goats. During the study, 3,347,797 animals were slaughtered. These included 621,686 cattle, 1,719,725 sheep and 1,006,386 goats. The prevalence of infection in cattle, sheep and goats was 12%, 14.6% and 10.1%, respectively. The association of condemnation rates with seasons was not proven statistically.  相似文献   
39.
In the very large areas of arid highlands in West Asia, of which land over 1000 m in Balochistan is typical, as a result of rapidly increasing numbers of small ruminants and subsequent overgrazing of natural rangelands, severe shortages in animal feed are being experienced. To address this problem the And Zone Research Institute (AZRI) have been evaluating annual forage legume germplasm for adaptability to the harsh climatic conditions of highland Balochistan. Due to the marginality of the environment for sustained crop production an unconventional germplasm evaluation strategy has been adopted which emphasizes the introduction of landraces, particularly of the genus Vicia. The substantial risk of crop failure from either cold or drought, in any year, makes continuity of seed supply of selected lines a major problem. Support from ICARDA in Syria for re-supply of seed is a major advantage to the AZRI program.
In the last three years some tangible progress has been made in selection. V. villosa ssp. dasycarpa Ace. 683 has with autumn sowing shown sufficient cold tolerance and is highly productive in wet years. V. ervilia Ace. 2542 has shown some potential for drought tolerance which could be exploited for spring sowing.  相似文献   
40.
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