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211.
The antibacterial, antifungal, acute cytotoxicity, phytotoxicity and insecticidal profile of the crude extract and various fractions of Indigofera gerardiana have been studied. Six bacterial and fungal strains were used, of which Samonella typhi and Microsporum canis were the most susceptible strains with MICs 0.37 mg/mL and 0.09 mg/mL, respectively. The crude extract and the fractions showed low insecticidal activity against Sitophilus oryzae, Rhyzopertha dominica and Callosbruchus analis but no activity against Tribolium castaneum. The brine shrimp lethality assay showed absence of any measurable cytotoxicity of the crude extract and fractions, showing a good safety profile at a preliminary level. All the fractions except crude extract revealed profound and highly significant herbicidal activity against Lemna minor at the concentration of 1000 microg/mL. Indigofera gerardiana was shown by in-vitro assays to be a potential source for natural antifungal, antibacterial and herbicidal agents.  相似文献   
212.
The sensitivity of the 197Au Mössbauer isomer shift and quadrupole splitting to gold oxidation state has enabled characterization of new stable, water—soluble Au(I) and Au(III) complexes of dimercaptosuccinic acid. The Au(I) complex exhibits a curious asymmetric line—broadening effect. Comparisons are also made with dimercaptopropanol and dithiocarbamate complexes. Relationships to existing and potential gold drugs are discussed.  相似文献   
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In most taxa, halving of chromosome numbers during meiosis requires that homologous chromosomes (homologues) pair and form crossovers. Crossovers emerge from the recombination-mediated repair of programmed DNA double-strand breaks (DSBs). DSBs are generated by SPO11, whose activity requires auxiliary protein complexes, called pre-DSB recombinosomes. To elucidate the spatiotemporal control of the DSB machinery, we focused on an essential SPO11 auxiliary protein, IHO1, which serves as the main anchor for pre-DSB recombinosomes on chromosome cores, called axes. We discovered that DSBs restrict the DSB machinery by at least four distinct pathways in mice. Firstly, by activating the DNA damage response (DDR) kinase ATM, DSBs restrict pre-DSB recombinosome numbers without affecting IHO1. Secondly, in their vicinity, DSBs trigger IHO1 depletion mainly by another DDR kinase, ATR. Thirdly, DSBs enable homologue synapsis, which promotes the depletion of IHO1 and pre-DSB recombinosomes from synapsed axes. Finally, DSBs and three DDR kinases, ATM, ATR and PRKDC, enable stage-specific depletion of IHO1 from all axes. We hypothesize that these four negative feedback pathways protect genome integrity by ensuring that DSBs form without excess, are well-distributed, and are restricted to genomic locations and prophase stages where DSBs are functional for promoting homologue pairing and crossover formation.  相似文献   
215.
Abstract

Calotropis procera is a perennial big shrub that has the potential to accumulate high concentrations of heavy metals. Metal sequestration in old organs has been considered as a mechanism for plant survival in polluted soils. The aim of the present study was to assess the role of the old leaves as a sink for HMs accumulation in C. procera. Two instruments were used: atomic absorption spectroscopy (AAS) and X-ray fluorescence (XRF) microscopy. Soil and plant samples were collected from around one of the worst congested traffic areas in the United Arab Emirates (UAE). Samples from roots, stem, and green and old leaves were prepared and analyzed by both instruments. Calotropis procera was able to concentrate Fe, Mn, Sr, and Zn in the roots, but their translocation to stem and green leaves was low. Old leaves had greater ability to accumulate significantly higher concentrations of different metals, especially Fe and Sr, than other parts of the plants, indicating that C. procera uses these metabolically less-active leaves as sinks for heavy metals. Fe and Sr attained higher bioconcentration and accumulation values, compared to Zn and Mn. There were significant positive correlations between XRF and AAS for all elements in the different organs.  相似文献   
216.
Although extensive research has been conducted to solve design and operational problems of automated manufacturing systems, many of the problems still remain unsolved. This article investigates the scheduling problems of flexible manufacturing systems (FMSs). Specifically, the relative performances of machine and automated guided vehicle (AGV) scheduling rules are analyzed against various due-date criteria. First, the relevant literature is briefly reviewed, and then the rules are tested under different experimental conditions by using a simulation model of an FMS. The sensitivity to AGV workload, buffer capacity, and processing-time distribution is also investigated to assess the robustness of the scheduling rules.  相似文献   
217.
Summary A triparental conjugation technique (using pRL10630 plasmid) was used in creation and characterization of three transposon-induced mutants of Anabaena PCC7120 which are capable of extracellular ammonia liberation in the absence and /or presence of a glutamate analogue (MSX). Results suggest that such mutants can potentially serve as suitable biofertilizer to support crops without addition of the glutamate analogue.  相似文献   
218.
Ali  Haider  Unar  Ahsanullah  Dil  Sobia  Ali  Imtiaz  Khan  Khalid  Khan  Ihsan  Shi  Qinghua 《Molecular biology reports》2022,49(7):6261-6268
Molecular Biology Reports - Fascins belong to a family of actin-bundling proteins that are involved in a wide range of biological functions. FSCN3, a newly identified testis-specific actin-bundling...  相似文献   
219.
220.
Abstract

Purpose

To evaluate the genotoxic effects of gold jewellery fumes and its association with GSTM1 and GSTT1 genetic polymorphisms.  相似文献   
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