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11.
Journal of Plant Growth Regulation - Salinity stress is one of the most important global problems that afflicts and limits the growth and development of turfgrass in arid and semi-arid areas....  相似文献   
12.

Low-temperature and high humidity are typical environmental factors in the plastic tunnel and solar greenhouse during the cold season that restricts plant growth and development. Herein, we investigated the impact of different combinations of low-temperature and high humidity (day/night: T1 15/10 °C?+?95%, T2 12/8 °C?+?95%, and T3 9/5 °C?+?95%) along with a control (CK 25/18 °C?+?80%) on cucumber cultivars viz: Zhongnong37 (ZN37: resistant) and Shuyanbailv (SYB: sensitive). The low-temperature and high humidity stresses increased electrolyte leakage (EL), malondialdehyde (MDA), hydrogen peroxide (H2O2) and intercellular concentration of carbon dioxide (Ci), and reduced morphological indices, relative water content (RWC), net photosynthesis rate (Pn), stomatal conductance (Gs), transpiration rate (E) and leaf pigments in both cultivars as compared to control (CK). Superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), ascorbate peroxidase (APX), monodehydroascorbate reductase (MDHAR), dehydroascorbate reductase (DHAR), and glutathione reductase (GR) were decreased in cv. SYB under stress conditions as compared to cv. ZN37. Low-temperature and high humidity treatments showed an increase in proline and soluble protein content in cv. ZN37 as compared to cv. SYB. Abscisic acid (ABA) and jasmonic acid (JA) were augmented while indole-3-acetic acid (IAA), zeatin (ZT), zeatin riboside (ZR), and gibberellic acid (GA) were decreased in both cultivars. Under T3 (9/5 °C?+?95%), Pn, protoporphyrin, and ZT were extremely decreased by 71.3%, 74.3%, and 82.4%, respectively, in cv. SYB compared to control. Moreover, principal component analysis (PCA) based on physiochemical traits confirmed that cv. ZN37 had the strongest correlation with antioxidant enzymes, proline, and soluble protein content than cv. SYB under low-temperature and high humidity treatments. Our results suggest that a stress-tolerant cultivar mitigates stress damage in cucumber transplants by regulating photosynthetic efficiency, antioxidant capacity and hormonal profile when compared to a stress-sensitive cultivar.

  相似文献   
13.
Cancer is one of the main challenges of the health system around the world. This disease is increasing in developing countries and imposes heavy costs on patients and governments. On the other hand, despite various drugs, the death rate among cancer patients is still high and the current treatments have many harmful effects. In the traditional medicine of different countries, there are many medicinal plants that can be effective in the treatment of cancer. Ferula plants are traditionally used as spices and food or for medicinal purposes. Ferula assa-foetida is one of the famous plants of this genus, which has been used for the treatment of various diseases since ancient times. Among the main compounds of this plant, we can mention monoterpenes, sulfide compounds and polyphenols, which can show different therapeutic effects. This article has been compiled with the aim of collecting evidence and articles related to the anti-cancer effects of extracts, derived compounds, essential oils and nanoparticles containing Ferula assa-foetida. This review article was prepared by searching the terms Ferula assa-foetida and cancer, and relevant information was collected through searching electronic databases such as ISI Web of Knowledge, PubMed, and Google Scholar. Fortunately, the results of this review showed that relatively comprehensive studies have been conducted in this field and shown that Ferula assa-foetida can be very promising in the treatment of cancer.  相似文献   
14.
15.
Summary In previous papers it was shown that the bacterium Zymomonas mobilis might be an interesting alternative for industrial alcohol production from sugar, compared to Saccharomyces bayanus. Factors that might increase the glucose to ethanol conversion efficiency and which are in favour of the bacterium, are the production of less biomass and less by-products such as glycerol, succinic acid, butanediol, acetoin, and acetic acid. In order to reduce the synthesis of biomass three metabolic inhibitors were now studied: dinitrophenol, azide and arsenate. Their effects on the alcoholic fermentation in batch and in immobilized cell system were investigated, using three yeasts: Saccharomyces bayanus, Schizosacharomyces pombe, and Saccharomyces diastaticus. It was found that dinitrophenol in 0.1 mM concentration was effective in increasing the conversion of glucose to ethanol especially with Saccharomyces bayanus while azide in 0.1 mM concentration was better with Schizosaccharomyces pombe. In immobilized systems high steady state ethanol production from 15% glucose media was obtained by inclusion into the media of dinitrophenol or azide. Arsenate had less effect at the concentration used. Arsenate had less effect at the concentrations used. As a result ethanol productivity in g·l-1·h-1 was increased from around 70 in the absence of inhibitor to around 74 in the presence of dinitrophenol with Saccharomyces bayanus. With Schizosaccharomyces pombe the productivity was increased from around 65 in the absence of inhibitor to around 74 in the presence of azide. The specific ethanol productivity expressed as g ethanol formed per hour and per g viable cells was increased from 0.87 to 1.37 for Schizosaccharomyces pombe and from 1.02 to 1.66 for Saccharomyces bayanus.  相似文献   
16.
Spore suspensions from 7 day old cultures of Curvularia lunata (Wakker) Boedijn var. aeria (Batista, Lima and Vasconcelos) M.B. Ellis were added to soil samples originally devoid of Curvularia propagules. The test fungus disappeared after six weeks of inoculation irrespective of soil amendments, like the application of green manure, urea, superphosphate, or soil cropped to Sorghum (dura) or cotton seedlings.  相似文献   
17.
Of 10 species of Nile fishes collected during the summer of 1975 at Giza near Cairo, Egypt, 7 harbored 7 helminth species. Recovered material includes 3 species of nematodes: Camallanus kirandensis Baylis 1928 (new host and geographical record), Cucullanus barbi Baylis 1923, and Rhabdochona congolensis Campana-Rouget 1961 (new host record); three species of cestodes: Khawia sp. (new in Africa), Polyonchobothrium clarias (Woodland 1925) Meggitt 1930, and Bothriocephalus aegyptiacus Rysavy and Moravec 1975; and one acanthocephalan species, Acanthosentis tilapiae Baylis 1947 (new geographical record). Morphologic observations of each species are reported. C. kirandensis and B. aegyptiacus are redescribed.  相似文献   
18.
Portulaca oleracea leaves were found to contain 0.42% of a mucilage mixture. The mucilage was fractionated into an acidic and a neutral fraction. The acidic fraction consists of galacturonic acid residues joined by α-(1→4)-linkages; 60% of these residues are present as the calcium salt, and esterified galacturonic acid residues are absent. The neutral fraction is composed of 41% of arabinose and 43% of galactose residues, besides traces of rhamnose residues.  相似文献   
19.
The effect of the tus protein-terB sequence complex of Escherichia coli on the movement of the SV40 large tumor antigen (T antigen)-mediated replication fork during SV40 DNA replication in vitro has been examined. In the monopolymerase and dipolymerase systems, the tus protein-terB complex efficiently blocked the replication fork movement in a polar fashion, as observed in prokaryotic replication systems. With crude cytosolic extracts of HeLa cells, the same polarity of fork arrest was observed, but the block of replication fork movement was inefficient. These results indicate that the structure of the prokaryotic tus protein-terB complex allows it to block replication fork movement in an orientation-dependent manner. We also show that the tus protein-terB complex blocks the 3'----5' helicase action of T antigen in a polar fashion, using substrates comprised of single-stranded M13 DNA with either a 52-base pair (bp) or 29-bp duplex containing the terB sequence. The tus protein-terB complex formed on the 52-bp duplex was less effective than the complex formed on the 29-bp duplex in blocking the helicase action of T antigen. With the 52-bp duplex substrate, T antigen movement was only partially (30%) blocked by the tus protein-terB sequence complex in the active orientation, whereas the E. coli dnaB helicase moving 5'----3' was blocked more than 90% by the complex in the active orientation. However, with the shorter 29-bp duplex substrate, the complex blocked the T antigen helicase activity about 75%, whereas the dnaB helicase activity was completely blocked. Altogether, these results suggest that the T antigen helicase activity, when coupled to DNA replication, is more susceptible to arrest by the tus protein-terB complex than the T antigen functioning as a helicase alone.  相似文献   
20.
Summary The possibility of usingZymomonas mobilis as the microorganism, in solid-state fermentation of sugar-beet particles was investigated. The major factors affecting the process were investigated and related to ethanol yield and productivity. Ethanol yield of 0.48 g/g sugar, volumetric productivity of 12 g/L h, and final ethanol concentration of 130 g/L show the good performance ofZ.mobilis in a solid-state fermentation.  相似文献   
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