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961.
Genetic variation in the DNA repair pathway as a potential determinant of response to platinum‐based chemotherapy in breast cancer
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![点击此处可从《Journal of cellular physiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
962.
The current status and perspectives regarding the clinical implication of intracellular calcium in breast cancer
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![点击此处可从《Journal of cellular physiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
963.
964.
Mona Eslami Mansour Bayat Amir Sasan Mozaffari Nejad Azar Sabokbar Amir Ali Anvar 《Saudi Journal of Biological Sciences》2016,23(3):341-347
Crocus sativus L. (saffron) is a valuable plant which is native to Iran. Saffron is the dried stigmata of the flowering part of the plant that is usually contaminated with different bacteria and fungi through production process. Antimicrobial properties of silver nanoparticles are well recognized. To survey the effects of nanosilver packaging on microbiological status of spiked, saffron samples over a six month period were chosen. Saffron samples from five regions of Khorasan province were purchased and de novo frequencies of microbial contaminants were determined using standard procedures. Totally 35 g of saffron was spiked with known numbers of four bacterial and two fungal species and packaged into one gram packets. The packaging materials consisted of polyethylene polymers containing 0, 400, 800, 1200 or 4000 ppm nanosilver (as Ag). Total and differential numbers of spiked microorganisms in the packaged saffrons were enumerated at initial and at six time points of seven, 14, 28, 64, 90 and 180 days. Baird-Parker agar (BP agar), Kenner Fecal (KF), Salmonella–Shigella agar (SS agar), Violet Red Bile Glucose Agar (VRBGA), and Sabouraud Dextrose agar (SD agar) media were used for enumeration of the six spiked microorganisms including Staphylococcus aureus, Enterococcus faecalis, Salmonella Enteritidis, Enterobacter species and Escherichia coli, Fusarium oxysporum and Aspergillus flavus, respectively. Direct antibacterial activity of the composites was also determined. De novo frequencies of microorganisms in five saffron samples were at acceptable levels with dominance of fungi species. Nanosilver embedded packages accelerated the reduction in live microbial numbers in saffron samples and the efficacy was the best in packages containing 4000 ppm nanosilver particles. Nanosilver packaging can significantly reduce microbial burden of saffron. 相似文献
965.
Tom Levy Ohad Rosen Brit Eilam Dudu Azulay Eliahu D. Aflalo Rivka Manor Assaf Shechter Amir Sagi 《Marine biotechnology (New York, N.Y.)》2016,18(5):554-563
Monosex culture, common in animal husbandry, enables gender-specific management. Here, production of all-female prawns (Macrobrachium rosenbergii) was achieved by a novel biotechnology comprising three steps: (a) A single injection of suspended hypertrophied androgenic gland cells caused fully functional sex reversal of females into “neo-males” bearing the WZ genotype; (b) crossing neo-males with normal females (WZ) yielded genomically validated WW females; and (c) WW females crossed with normal males (ZZ) yielded all-female progeny. This is the first sustainable biotechnology for large-scale all-female crustacean aquaculture. The approach is particularly suited to species in which females are superior to males and offers seedstock protection, thereby ensuring a quality seed supply. Our technology will thus revolutionize not only the structure of the crustacean aquaculture industry but can also be applied to other sectors. Finally, the production of viable and reproducible females lacking the Z chromosome questions its role, with respect to sexuality. 相似文献
966.
Development of broad virus resistance in non‐transgenic cucumber using CRISPR/Cas9 technology
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![点击此处可从《Molecular Plant Pathology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Jeyabharathy Chandrasekaran Marina Brumin Dalia Wolf Diana Leibman Chen Klap Mali Pearlsman Amir Sherman Tzahi Arazi Amit Gal‐On 《Molecular Plant Pathology》2016,17(7):1140-1153
Genome editing in plants has been boosted tremendously by the development of CRISPR/Cas9 (Clustered Regularly Interspaced Short Palindromic Repeats) technology. This powerful tool allows substantial improvement in plant traits in addition to those provided by classical breeding. Here, we demonstrate the development of virus resistance in cucumber (Cucumis sativus L.) using Cas9/subgenomic RNA (sgRNA) technology to disrupt the function of the recessive eIF4E (eukaryotic translation initiation factor 4E) gene. Cas9/sgRNA constructs were targeted to the N′ and C′ termini of the eIF4E gene. Small deletions and single nucleotide polymorphisms (SNPs) were observed in the eIF4E gene targeted sites of transformed T1 generation cucumber plants, but not in putative off‐target sites. Non‐transgenic heterozygous eif4e mutant plants were selected for the production of non‐transgenic homozygous T3 generation plants. Homozygous T3 progeny following Cas9/sgRNA that had been targeted to both eif4e sites exhibited immunity to Cucumber vein yellowing virus (Ipomovirus) infection and resistance to the potyviruses Zucchini yellow mosaic virus and Papaya ring spot mosaic virus‐W. In contrast, heterozygous mutant and non‐mutant plants were highly susceptible to these viruses. For the first time, virus resistance has been developed in cucumber, non‐transgenically, not visibly affecting plant development and without long‐term backcrossing, via a new technology that can be expected to be applicable to a wide range of crop plants. 相似文献
967.
968.
Traditional marijuana,high‐potency cannabis and synthetic cannabinoids: increasing risk for psychosis
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![点击此处可从《World psychiatry》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Robin M. Murray Harriet Quigley Diego Quattrone Amir Englund Marta Di Forti 《World psychiatry》2016,15(3):195-204
Epidemiological evidence demonstrates that cannabis use is associated with an increased risk of psychotic outcomes, and confirms a dose‐response relationship between the level of use and the risk of later psychosis. High‐potency cannabis and synthetic cannabinoids carry the greatest risk. Experimental administration of tetrahydrocannabinol, the active ingredient of cannabis, induces transient psychosis in normal subjects, but this effect can be ameliorated by co‐administration of cannabidiol. This latter is a constituent of traditional hashish, but is largely absent from modern high‐potency forms of cannabis. Argument continues over the extent to which genetic predisposition is correlated to, or interacts with, cannabis use, and what proportion of psychosis could be prevented by minimizing heavy use. As yet, there is not convincing evidence that cannabis use increases risk of other psychiatric disorders, but there are no such doubts concerning its detrimental effect on cognitive function. All of the negative aspects are magnified if use starts in early adolescence. Irrespective of whether use of cannabis is decriminalized or legalized, the evidence that it is a component cause of psychosis is now sufficient for public health messages outlining the risk, especially of regular use of high‐potency cannabis and synthetic cannabinoids. 相似文献
969.
Guillermo Martínez Pérez Vivian Cox Tom Ellman Ann Moore Gabriela Patten Amir Shroufi Kathryn Stinson Gilles Van Cutsem Maryrene Ibeto 《PloS one》2016,11(4)
Reaching universal HIV-status awareness is crucial to ensure all HIV-infected patients access antiretroviral treatment (ART) and achieve virological suppression. Opportunities for HIV testing could be enhanced by offering self-testing in populations that fear stigma and discrimination when accessing conventional HIV Counselling and Testing (HCT) in health care facilities. This qualitative research aims to examine the feasibility and acceptability of unsupervised oral self-testing for home use in an informal settlement of South Africa. Eleven in-depth interviews, two couple interviews, and two focus group discussions were conducted with seven healthcare workers and thirteen community members. Thematic analysis was done concurrently with data collection. Acceptability to offer home self-testing was demonstrated in this research. Home self-testing might help this population overcome barriers to accepting HCT; this was particularly expressed in the male and youth groups. Nevertheless, pilot interventions must provide evidence of potential harm related to home self-testing, intensify efforts to offer quality counselling, and ensure linkage to HIV/ART-care following a positive self-test result. 相似文献
970.
Xue Qing Holly Bik Timur M. Yergaliyev Jianfeng Gu Pamela Fonderie Sigal Brown‐Miyara Amir Szitenberg Wim Bert 《Molecular ecology resources》2020,20(1):318-332
Ribosomal RNA genes have long been a favoured locus in phylogenetic and metabarcoding studies. Within a genome, rRNA loci are organized as tandem repeated arrays and the copies are homogenized through the process of concerted evolution. However, some level of rRNA variation (intragenomic polymorphism) is known to persist and be maintained in the genomes of many species. In nematode worms, the extent of rRNA polymorphism (RP) across species and the evolutionary and life history factors that contribute to the maintenance of intragenomic RP is largely unknown. Here, we present an extensive analysis across 30 terrestrial nematode species representing a range of free‐living and parasitic taxa isolated worldwide. Our results indicate that RP is common and widespread, ribosome function appears to be maintained despite mutational changes, and intragenomic variants are stable in the genome and neutrally evolving. However, levels of variation were varied widely across rRNA locus and species, with some taxa observed to lack RP entirely. Higher levels of RP were significantly correlated with shorter generation time and high reproductive rates, and population‐level factors may play a role in the geographic and phylogenetic structuring of rRNA variants observed in genera such as Rotylenchulus and Pratylenchus. Although RP did not dramatically impact the clustering and recovery of taxa in mock metabarcoding analyses, the present study has significant implications for global biodiversity estimates of nematode species derived from environmental rRNA amplicon studies, as well as our understanding of the evolutionary and ecological factors shaping genetic diversity across the nematode Tree of Life. 相似文献