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861.
Ismail BS  Ampong N  Omar O 《Microbios》2000,103(405):73-83
Effects of metsulphuron-methyl on the activities of amylase, invertase and xylanase in loamy sand and clay were evaluated for up to 28 days under laboratory conditions. Metsulphuron-methyl at 1.0 microg/g caused a significant reduction in amylase, invertase and xylanase activities for the entire period of study, especially at 28 days incubation in both soils. The lowest activities of the three enzymes were observed in the presence of 5.0 microg/g at 28 days incubation.  相似文献   
862.
Functional & Integrative Genomics - Congenital diaphragmatic hernia (CDH) is an anomaly characterized by a defect in the diaphragm, leading to the passage of intra-abdominal organs into the...  相似文献   
863.
Aortoiliac disease often coexists with coronary artery disease. It is not uncommon to subject a patient to two separate interventions. We report two cases in which in simultaneous off-pump coronary artery bypass grafting was done with an ascending aortobifemoral bypass graft through the ventral abdominal route without any additional morbidity. Combining a technically simple method of limb bypass with an off-pump cardiac surgery is a promising procedure for revascularization of myocardium and lower limbs. We discuss the merits of combining an off-pump coronary artery bypass grafting procedure with a limb bypass.  相似文献   
864.
865.
866.
Tragopogon dubius and Tussilago farfara are consumed as vegetables and used in folk medicine to manage common diseases. Herein, the chemical compositions and biological activities of different leaf extracts (ethyl acetate, methanol, and water) of T. dubius and T. farfara were evaluated. The antibacterial, antifungal, and antioxidant abilities of the extracts were tested using different assays including free radical scavenging, reducing power, phosphomolybdenum, and metal chelating assays. Enzyme inhibitory potentials were evaluated against cholinesterases, tyrosinase, α-amylase and α-glucosidase. Complexes of bioactive compounds (chlorogenic and rosmarinic acid) were docked into the enzymatic cavity of α-glucosidase and subjected to molecular dynamic calculation, enzyme conformational stability, and flexibility analysis. T. dubius and T. farfara extracts showed remarkable antioxidant potentials. Ethyl acetate extracts of T. dubius and T. farfara were the most potent inhibitors of acetylcholinesterase and butyrylcholinesterase. T. dubius ethyl acetate extract and T. farfara methanolic extract showed noteworthy activity against α-glucosidase. High performance liquid chromatography analysis revealed the abundance of some phenolic compounds including chlorogenic and rosmarinic acids. Ethyl acetate extract of T. dubius showed notable antifungal activity against all strains. Docking studies showed best pose for chlorogenic acid was stabilized by a network of hydrogen bonds with residues Asp1157, Asp1279, whereas rosmarinic acid showed several hydrogen bonds with Asp1157, Asp1420, Asp1526, Lys1460 and Trp1369. This study further validates the use of T. dubius and T. farfara in traditional medicine, as well as act as a stimulus for further studies for future biomedicine development.

Communicated by Ramaswamy H. Sarma  相似文献   

867.
Insomnia is a condition characterized by three nocturnal symptoms: problems with sleep onset or maintenance and early morning awakenings (terminal insomnia). Affected individuals may present one or more of these symptoms. Several studies have shown that insomnia is moderately heritable and that proxy phenotypes for the three insomnia symptoms show different heritabilities. This suggests that different nocturnal symptoms of insomnia may arise from different genetic and biological backgrounds. Circadian genes are good candidates to account for these differences as they regulate the periodicity of several physiological functions including sleep. Evidence from studies in animals and humans have suggested that circadian genes might be involved in sleep disturbances such as insomnia. In this study, we investigated the association between Single Nucleotide Polymorphisms (SNPs) in circadian genes and individual symptoms of insomnia and their combinations using data from the Nord-Trøndelag Health Study 3 (the HUNT3 study, N = 50807). Participants (N = 6029) provided information about sleep onset insomnia, maintenance insomnia, and terminal insomnia. Participants who responded “several times a week” to at least one question regarding the mentioned symptoms were classified as cases (N = 3577) and categorized in seven subgroups according to possible symptom combinations. Controls (N = 2452) answered “Never/Seldom” to all sleep-related questions. Using multinomial regression, we assessed 73 SNPs in nine circadian genes (PER1, 2, 3, CRY1, 2, TIMELESS, CLOCK, REV-ERBα, ARNTL) for differences among symptoms subgroups. Twenty-five SNPs showed significant p-values and supportive odds-ratios. All significant SNPs in PER3 were associated with reporting all three symptoms simultaneously. SNPs in CRY genes were associated with terminal insomnia alone or in combination with other symptoms. Genes PER1 and two were mostly associated with sleep maintenance insomnia. However, none of the SNPs remained significant after False Discovery Rate (FDR) correction for multiple statistical testing. In conclusion, even though none of the SNPs remained significant after FDR correction, the clustering of some genes around specific symptoms points to the need for additional research on these relationships.  相似文献   
868.
This study was undertaken to investigate the protective effects of melatonin against formaldehyde-induced neurotoxicity in prefrontal cortex of rats. For this purpose, 21 male Wistar rats were divided into three groups. The rats in Group I were used as a control, while the rats in Group II were injected every other day with formaldehyde. The rats in Group III received melatonin daily while exposed to formaldehyde. At the end of 14-day experimental period, all rats were killed by decapitation. The brains of the rats were removed and the prefrontal cortex tissues were obtained from all brain specimens. Some of the prefrontal cortex tissue specimens were used for determination of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and malondialdehyde (MDA) levels. The remaining prefrontal cortex tissue specimens were used for immunohistochemical evaluation. The levels of SOD and GSH-Px were significantly decreased, and MDA levels, were significantly increased in rats treated with formaldehyde compared with those of the controls. In the immunohistochemical evaluation of this group, apoptotic cells were observed. However, increased SOD and GSH-Px enzyme activities, and decreased MDA levels, were detected in the rats administered melatonin while exposed to formaldehyde. Furthermore, apoptotic changes caused by formaldehyde were decreased in these rats. The results of our study suggest that melatonin treatment prevents formaldehyde-induced neuronal damage in prefrontal cortex.  相似文献   
869.
Rice brown spot, caused by Bipolaris oryzae, can be a serious disease causing a considerable yield loss. Trichoderma harzianum is an effective biocontrol agent for a number of plant fungal diseases. Thus, this research was carried out to investigate the mechanisms of action by which T. harzianum antagonizes Bipolaris oryzae in vitro, and the efficacy of spray application of a spore suspension of T. harzianum for control of rice brown spot disease under field conditions. In vitro, the antagonistic behavior of T. harzianum resulted in the overgrowth of B. oryzae by T. harzianum, while the␣antifungal metabolites of T.␣harzianum completely prevented the linear growth of B. oryzae. Light and scanning electron microscope (SEM) observations showed no evidence that mycoparasitism contributed to the aggressive nature of the tested isolate of T. harzianum against B. oryzae. Under field conditions, spraying of a spore suspension of T. harzianum at 108 spore ml−1 significantly reduced the disease severity (DS) and disease incidence (DI) on the plant leaves, and also significantly increased the grain yield, total grain carbohydrate, and protein, and led to a significant increase in the total photosynthetic pigments (chlorophyll a and b and carotenoids) in rice leaves.  相似文献   
870.
Cadmium (Cd) accumulation in durum wheat grain is a growing concern. Among the factors affecting Cd accumulation in plants, soil chloride (Cl) concentration plays a critical role. The effect of leaf NaCl application on grain Cd was studied in greenhouse-grown durum wheat (Triticum turgidum L. durum, cv. Balcali-2000) by immersing (10 s) intact flag leaves into Cd and/or NaCl-containing solutions for 14 times during heading and dough stages. Immersing flag leaves in solutions containing increasing amount of Cd resulted in substantial increases in grain Cd concentration. Adding NaCl alone or in combination with the Cd-containing immersion solution promoted accumulation of Cd in the grains, by up to 41%. In contrast, Zn concentrations of grains were not affected or even decreased by the NaCl treatments. This is likely due to the effect of Cl complexing Cd and reducing positive charge on the metal ion, an effect that is much smaller for Zn. Charge reduction or removal (CdCl20 species) would increase the diffusivity/lipophilicity of Cd and enhance its capability to penetrate the leaf epidermis and across membranes. Of even more significance to human health was the ability of Cl alone to penetrate leaf tissue and mobilize and enhance shoot Cd transfer to grains, yet reducing or not affecting Zn transfer.  相似文献   
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