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241.
The frequency of isoniazid slow inactivators is very high among Eqyptians, 82% have more than 0.91 γ/ml of free INH in serum specimens obtained six hours after a single dose of 10 mgm/kgm. The incidence of the allele for INH acetylase enzyme deficiency is estimated at 0.9059 and that of the heterozygous carrier of this allele at 0.1705.  相似文献   
242.
Journal of Plant Research - Potato plants are often exposed to biotic and abiotic stresses that negatively impact their growth, development, and yield. Plants respond to different stresses by...  相似文献   
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The aim of the present study was to investigate the protective role of grape seed extract (containing proanthocyandin) against the adverse effects of plant growth regulators (GA3 (gibberellic acid) and IAA (indoleacetic acid)). The present data showed that the administration of either GA3 and IAA caused undesirable changes in both hepatic and testicular structure. This was evidenced by a disturbed hepatic strands, pyknotic nuclei, central vein with collapsed endothelium, dilatation in bile sinusoids, congested blood vessel, binucleatd hepatocytes, lymphocytic infiltration, vacuolation, giant hepatic cells, increased Kupffer cells and karyoryxis. Additionally, it was shown that degenerative changes in the testis, spermatogenic arrest, moderate tubular necrosis, Leydig cell degeneration and reduction in the number and size of the seminiferous tubules with some spermatogonia detached from the basement membrane. Concerning flow cytometric study of the liver a significant decrease in G0/1 % and a significant increase in S phase %, G2/M  %, P53 % and apoptosis % (sub G1) were detected. However, in testis the data recorded a significant decrease in the percentage of mature sperm (percentage of haploid cells) and a significant increase in the percentage of spermatide, diploid cells, P53 and of apoptotic cells. On the other hand, a distinct recovery of the mentioned hepatic and testicular histopathological and cytogenetic disorders was observed when proanthocyanidin was supplemented to rats administered either of the plant growth hormones (GA3 and IAA).  相似文献   
245.
A continuous enrichment culture procedure was used to isolate bacteria from various soil sources capable of suppressing summer patch disease of turfgrass. Cultures consisted of a minimal salts medium supplemented with the mycelium of Magnaporthe poae, the causal agent of summer patch, as the sole carbon source. Percentages of chitinolytic bacteria increased in all enrichments over time. Approximately 30% of randomly selected isolates from enrichment cultures significantly reduced summer patch symptom development compared with untreated controls. Six isolates consistently suppressed summer patch in Kentucky bluegrass by more than 50% compared with controls in repeated experiments. All six isolates colonized the turfgrass rhizosphere in high populations. The six isolates ranged in the spectrum of extracellular enzymes that they expressed. The best disease-suppressing isolate, N4-7, expressed chitinase, glucanase, lipase, and protease activity, and inhibited the growth of M. poae in vitro.  相似文献   
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Calendula suffruticosa Vahl subsp. boissieri Lanza is well-known for its medicinal properties in northeastern Algeria. As far as literature has been able to prove, no study has attempted to make a phytochemical or biological activity evaluation (antioxidants, enzyme inhibitors and antimicrobial potential). This work intends to evaluate, for the first time, the chemical constituents and study the previously mentioned biological activities of C. suffruticosa boissieri essential oil and different sections (flowers, leaves, roots) as well as the effect of changing the solvent (ethanol 70 %) and (methanol 70 %) on these activities. The essential oil of aerial parts of this plant was investigated using GC/MS, and 45 compounds were discovered, accounting for 98.01 % of the essential oil, including 23 monoterpenes, 6 sesquiterpenes, 12 diterpenes, 1 coumarin, 3 alkanes, methyl-cyclohexane (23.73 %), limonene (25.02 %), and o-cymene (13.20 %). Five methods were used to study the antioxidant activity (ABTS, DPPH, CUPRAC, reducing power, and β-carotene bleaching assay), where the results were impressive, especially for the essential oil. In addition, the hydroethanolic solvent (70 %) was found to be the most effective solvent for extraction in general compared to the hydromethanolic solvent (70 %). The extracts and essential oils of C. suffruticosa boissieri also showed a strong inhibiting ability against cholinesterase, tyrosinase, anti-α-amylase, α-glucosidase, and antimicrobials, a very valuable antioxidant, which is a real discovery. Based on these results, it can be said that this plant has important biological activities, so it can be used in the phytotherapy, food, or pharmaceutical sectors.  相似文献   
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