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851.
Somatic embryogenesis of cucumber was affected by auxin and light during the induction phase. In the light, 2,4-dichlorophenoxyacetic acid (2,4-D) alone induced little embryogenesis, while combined with naphthaleneacetic acid (NAA) it induced 1.25 somatic embryos (SEs) per callus. In the dark 2,4-D alone induced 5 times more SEs per callus.  相似文献   
852.
BackgroundPeripheral neuropathy (PN) is the damage and dysfunction of neurons of the peripheral nervous system. The present study was conducted to estimate the effectiveness of low-power laser therapy (LPLT) in the management of PN in a rats’ model.MethodsPN was induced by giving dichloroacetate (DCA) (250 mg/kg/day) for up to 12 weeks. Four groups of rats were used: control group, PN group, PN group treated with gabapentin and PN group treated with LPLT. The study was conducted for 8 weeks. The management of PN was estimated by behavioral tests which included hot plate and Morris water maze tests. Blood biochemical analysis were carried out.ResultsUsing of hot plate test indicated thermal hypoalgesia and using Morris water maze test showed cognitive decline in PN rats. Treatment with LPLT or gabapentin improved both the pain sensations and deteriorated memory that occurred in the PN rats. Biochemical analysis showed that LPLT significantly decreased the elevated beta-endorphin level in PN rats, while gabapentin could not reduce it. Treatment PN rats with LPLT or gabapentin shifted the high levels of TNF-α, IL-1β and IL-10 cytokines back to their normal values. Serum nitric oxide and MDA significantly increased in the PN group together with significant reduction in the rGSH level, these values were significantly improved by LPLT application while this was not the case with gabapentin treatment. Furthermore, treatment with gabapentin or LPLT significantly reduced serum ALAT and ASAT activities which are otherwise increased in the PN group. S100B, PGE2, total cholesterol, triglycerides, LDL-cholesterol, HDL-cholesterol, urea and creatinine showed insignificant changes among all groups.ConclusionsOur results showed that treatment with LPLT is more efficient than gabapentin in ameliorating the peripheral neuropathy induced by xenobiotics.  相似文献   
853.
Summary A research program to develop an in vitro culture technique adapted to very immature Phaseolus zygotic embryos indicated that osmolality within young pods in vivo ranged from 580 to 350 mosm during the first 10 d after pollination. Different culture techniques for 2-d-old Phaseolus pods are described using a modified Phillips medium for maturation. The application of high and variable osmolality conditions, similar to what is observed in vivo, during pod culture (1 wk) and before extracting the embryos, gave the best results in terms of ovule and embryo development. To solve contamination problems affecting pod development during these investigations, a sterilizing technique was tested combining various concentrations of polyoxyethylenesorbitan monolaurate (Tween 20) and a broad-spectrum industrial biocide, Plant Preservative Mixture (PPM). The PPM sterilizing method totally eliminated pod contamination and did not affect ovule growth, but significantly reduced the embryo germination rate.  相似文献   
854.
855.
The present paper will focus on the developments in our lab related to the origin of the code since the Israel meeting (1,2). Principally these items are: (a) a new set of correlations (3) which include ranked hydrophobicities of amino acids and dinucleotides; (b) binding constants (4) of Phe for the four mononucleotides; and (c) binding constants (5) of Phe, Leu, Ile, Val, and Gly for polyadenylic acid (poly A). The data continue to support a model for the origin of the code based on relationships between amino acids and their anticodons.  相似文献   
856.
Metabolites of azo dyes are often carcinogenic, teratogenic, mutagenic and recalcitrant in nature. In this study, four biofilm consortia such as C1 (Vitreoscilla sp. ENSG301, Acinetobacter lwoffii ENSG302, Klebsiella pneumoniae ENSG303 and Pseudomonas fluorescens ENSG304), C2 (Escherichia coli ENSD101, Enterobacter asburiae ENSD102 and E. ludwigii ENSH201), C3 (E. asburiae ENSD102, Vitreoscilla sp. ENSG301 and Bacillus thuringiensis ENSW401), and C4 (E. coli ENSD101, E. ludwigii ENSH201 and B. thuringiensis ENSW401) were applied to degrade and detoxify methyl orange (MO), a carcinogenic, sulfonated mono azo dye, used in textile dyeing industry worldwide. The consortia of C1, C2, C3 and C4 showed 97.30, 98.75, 99.51 and 99.29% decolorization, respectively in yeast extract peptone (YEP) broth containing 200 mg L−1 MO within 60 h of incubation in static condition. The optimum pH and temperature for decolorization was 7.0 and 28 °C, respectively. Some divalent metal ions including Mg2+, Ca2+, Zn2+ and Mn2+ could stimulate MO decolorization. UV–Vis spectral analysis showed that the absorption peak at 465 nm originated from the azo (N Created by potrace 1.16, written by Peter Selinger 2001-2019 N) bond was completely disappeared within 60 h of incubation. Fourier transform infrared spectroscopy (FTIR) results also revealed that several major peaks including azo bond peak at 1602.6 cm−1 are completely or partly vanished, deformed or shifted. Activities of azoreductase, NADH-DCIP reductase and laccase were significantly increased in the bacterial cells within 60 h of incubation in comparison to that of control (0 h). The chemical oxygen demand was incredibly reduced by 85.37 to 91.44% by these consortia. Accordingly, plant (wheat seed germination) and microbial (growth of the plant probiotic bacteria such as Pseudomonas cedrina ESR12 and Bacillus cereus ESD3 on biodegraded products) toxicity studies showed that biodegraded products of MO are non-toxic. Thus, all these consortia can be utilized in bioremediation of MO from wastewater for safe disposal into environment. To our knowledge, this is the first report on degradation and detoxification of MO from wastewater by bacterial biofilm consortia.  相似文献   
857.

Background  

Two potential migratory routes followed by modern humans to colonize Eurasia from Africa have been proposed. These are the two natural passageways that connect both continents: the northern route through the Sinai Peninsula and the southern route across the Bab al Mandab strait. Recent archaeological and genetic evidence have favored a unique southern coastal route. Under this scenario, the study of the population genetic structure of the Arabian Peninsula, the first step out of Africa, to search for primary genetic links between Africa and Eurasia, is crucial. The haploid and maternally inherited mitochondrial DNA (mtDNA) molecule has been the most used genetic marker to identify and to relate lineages with clear geographic origins, as the African Ls and the Eurasian M and N that have a common root with the Africans L3.  相似文献   
858.
Summary Frequency estimates were determined on seventeen blood group, serum protein, and red-cell enzyme markers on random samples of 193 individuals from two Bedouin tribes in addition to the general population in Kuwait. Genetic heterogeneity between the three communities is evident from the significant differences in allelic distribution of the polymorphic markers.Genetic distance measurements were used to compare the results with the oral history of descent of the two tribal communities. Results were in agreement with tribal history.  相似文献   
859.
Cytotoxic T-lymphocytes (CTLs) kill abnormal cells. CTLs recognize major histocompatibility complex class I molecules in complex with peptides derived from relevant antigens. The identification of tumor associated antigen peptides enabled the design of anti-tumor and anti-metastatic vaccines in a murine lung carcinoma.  相似文献   
860.
Abstract

The levels of some potentially toxic metals (Cr, Mn, Fe, Co, Cu, Zn, Cd, and Pb) were quantified in 60 street dust samples from Khamees-Mushait city, Saudi Arabia. Samples were taken from three locations at each functional area (total 18 including traffic, industrial, residential, and workshops) and at each control area (total two including a park and a new domestic planner). Heavy metals concentrations were quantified in less than 106 µm particle-size using inductively-coupled plasma-optical emission spectrometer after microwave wet digestion. The total concentrations (µg/g) were in the ranges of Cr 128.48–277.53, Mn 589.43–1091.45, Fe 43478.26–99151.63, Co 23.04–55.22, Cu 10.46–176.13, Cd 0.30–1.99, and Pb 9.36–340.56. The accuracy of results was examined using standard quality control samples, spiking, and a certified reference material. The overall recovery was in the range of 86.2–113.3%. The enrichment factors and the geoaccumulation indices, besides principal component analysis, reveal various levels of enrichment by Fe, Cu, Zn, and Pb from functional areas of congested traffic, commercial activities, and metallic workshops activities. In contrast, no significant enrichment by Cr, Mn, and Co was recorded. The cluster analysis revealed that the metallic workshops and the vehicle scrap workshops are the hottest functional areas.  相似文献   
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