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1.
Piophila megastigmata McAlpine (Diptera: Piophilidae) is recorded for the first time from Algeria, northern Africa. This is the first Palaearctic record of the species outside the Iberian Peninsula, and the only record from Africa apart from its type locality in eastern South Africa. The current report extends significantly the known distribution in the Palaearctic Region of a species of forensic interest and of potential economic importance as a food pest.  相似文献   
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Plant and Soil - Plant growth promoting bacteria (PGPB) containing 1-aminocyclopropane-1-carboxylate (ACC) deaminase can play an important role in abiotic stress tolerance in plants, particularly...  相似文献   
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Saifi B  Ferat JL 《PloS one》2012,7(3):e33613
Replicative helicases unwind double-stranded DNA in front of the polymerase and ensure the processivity of DNA synthesis. In Escherichia coli, the helicase loader DnaC as well as factors involved in the formation of the open complex during the initiation of replication and primosomal proteins during the reactivation of arrested replication forks are required to recruit and deposit the replicative helicase onto single-stranded DNA prior to the formation of the replisome. dnaC2 is a thermosensitive allele of the gene specifying the helicase loader; at non-permissive temperature replication cannot initiate, but most ongoing rounds of replication continues through to completion (18% of dnaC2 cells fail to complete replication at non-permissive temperature). An assumption, which may be drawn from this observation, is that only a few replication forks are arrested under normal growth conditions. This assumption, however, is at odds with the severe and deleterious phenotypes associated with a null mutant of priA, the gene encoding a helicase implicated in the reactivation of arrested replication forks. We developed an assay that involves an abrupt inactivation of rounds of synchronized replication in a large population of cells, in order to evaluate the ability of dnaC2 cells to reactivate arrested replication forks at non-permissive temperature. We compared the rate at which arrested replication forks accumulated in dnaC2 priA(+) and dnaC2 priA2 cells and observed that this rate was lower in dnaC2 priA(+) cells. We conclude that while replication cannot initiate in a dnaC2 mutant at non-permissive temperature, a class of arrested replication forks (PriA-dependent and DnaC-independent) are reactivated within these cells.  相似文献   
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We describe a novel mutation in the coding region of theSRY gene in a 46, XY female with Swyer syndrome. Analysis ofSRY was carried out by direct sequencing of a 780-bp PCR product that included theSRY open reading frame (ORF). This revealed the presence of a point mutation, ins 108A, in the coding region 5’ to the HMG box which results in a frame shift and premature termination of the encoded protein. No other mutation was found in theSRY ORF. We infer that sex reversal in this individual is a result of this insertion. In none of the 13 other 46, XY females that were studied was a mutation detected inSRY, confirming earlier findings that most cases of XY femaleness are due to causes other than mutation inSRY. These observations and those of others are discussed in relation to the aetiology of XY sex reversal.  相似文献   
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We describe here the results of a search of Mendelian inheritance in man, GENDIAG and other sources which suggest that, in comparison with autosomes 1, 2, 3, 4 and 11, the X chromosome may contain a significantly higher number of sex- and reproduction-related (SRR) genes. A similar comparison between X-linked entries and a subset of randomly chosen entries from the remaining autosomes also indicates an excess of genes on the X chromosome with one or more mutations affecting sex determination (e.g. DAX1), sexual differentiation (e.g. androgen receptor) or reproduction (e.g. POF1). A possible reason for disproportionate occurrence of such genes on the X chromosome could be that, during evolution, the 'choice' of a particular pair of homomorphic chromosomes for specialization as sex chromosomes may be related to the number of such genes initially present in it or, since sex determination and sexual dimorphism are often gene dose-dependent processes, the number of such genes necessary to be regulated in a dose-dependent manner. Further analysis of these data shows that XAR, the region which has been added on to the short arm of the X chromosome subsequent to eutherian-marsupial divergence, has nearly as high a proportion of SRR genes as XCR, the conserved region of the X chromosome. These observations are consistent with current hypotheses on the evolution of sexually antagonistic traits on sex chromosomes and suggest that both XCR and XAR may have accumulated SRR traits relatively rapidly because of X linkage.  相似文献   
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Two new bi-pyridine compounds, [1,4'] Bipiperidinyl-1'-yl-naphthan-2-yl-methanone (I) and [1,4'] Bipiperidinyl-1'-yl-4-methylphenyl-methane (II) were synthesized and examined for inhibition of the catecholase activity of mushroom tyrosinase in 10 mM phosphate buffer pH 6.8, at 293 K using UV spectrophotometry. Inhibition kinetics indicated that they were uncompetitive inhibitors and the value of the inhibition constants were 5.87 and 1.31 microM for I and II, respectively, which showed high potency. Fluorescent studies confirmed the uncompetitive type of inhibition for these two inhibitors. The inhibition mechanism presumably comes from the presence of a particular hydrophobe site which can accommodate these inhibitors. This site could be formed due to a probable conformational change that was induced by binding of substrate with the enzyme.  相似文献   
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Sensing stress and activating the downstream signaling pathways is the imperative step for stress response. Lectin receptor-like kinase (LecRLK) is an important family that plays a key role in sensing stress conditions through lectin receptor and activates downstream signaling by kinase domain. We identified the role of OsLecRLK gene for salinity stress tolerance and hypothesized its role in Na+ extrusion from cell. OsLecRLK overexpression and downregulation (through artificial miRNA) transgenic lines were developed and its comparison with wild-type (WT) plants were performed overexpression transgenic lines showed better performance, whereas downregulation showed poor performance than WT. Lower accumulation of reactive oxygen species (ROS), malondialdehyde and toxic ion, and a higher level of proline, RWC, ROS scavengers in overexpression lines lead us to the above conclusion. Based on the relative expression of stress-responsive genes, ionic content and interactome protein, working model highlights the role of OsLecRLK in the extrusion of Na+ ion from the cell. This extrusion is facilitated by a higher expression of salt overly sensitive 1 (Na+/K+ channel) in overexpression transgenic line. Altered expression of stress-responsive genes and changed biochemical and physiological properties of cell suggests an extensive reprogramming of the stress-responsive metabolic pathways by OsLecRLK under stress condition, which could be responsible for the salt tolerance capability.  相似文献   
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Background

A comparative food ethnobotanical study was carried out in fifteen local communities distributed in five districts in the Palestinian Authority, PA (northern West Bank), six of which were located in Nablus, two in Jenin, two in Salfit, three in Qalqilia, and two in Tulkarm. These are among the areas in the PA whose rural inhabitants primarily subsisted on agriculture and therefore still preserve the traditional knowledge on wild edible plants.

Methods

Data on the use of wild edible plants were collected for one-year period, through informed consent semi-structured interviews with 190 local informants. A semi-quantitative approach was used to document use diversity, and relative importance of each species.

Results and discussion

The study recorded 100 wild edible plant species, seventy six of which were mentioned by three informants and above and were distributed across 70 genera and 26 families. The most significant species include Majorana syriaca, Foeniculum vulgare, Malvasylvestris, Salvia fruticosa, Cyclamen persicum, Micromeria fruticosa, Arum palaestinum, Trigonella foenum-graecum, Gundelia tournefortii, and Matricaria aurea. All the ten species with the highest mean cultural importance values (mCI), were cited in all five areas. Moreover, most were important in every region. A common cultural background may explain these similarities. One taxon (Majoranasyriaca) in particular was found to be among the most quoted species in almost all areas surveyed. CI values, as a measure of traditional botanical knowledge, for edible species in relatively remote and isolated areas (Qalqilia, and Salfit) were generally higher than for the same species in other areas. This can be attributed to the fact that local knowledge of wild edible plants and plant gathering are more spread in remote or isolated areas.

Conclusion

Gathering, processing and consuming wild edible plants are still practiced in all the studied Palestinian areas. About 26 % (26/100) of the recorded wild botanicals including the most quoted and with highest mCI values, are currently gathered and utilized in all the areas, demonstrating that there are ethnobotanical contact points among the various Palestinian regions. The habit of using wild edible plants is still alive in the PA, but is disappearing. Therefore, the recording, preserving, and infusing of this knowledge to future generations is pressing and fundamental.  相似文献   
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