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991.
Polymorphic microsatellite markers for stock identification in Japanese anchovy (Engraulis japonica)
Tai‐Sheng Chiu Yann‐Jium Lee Shiao‐Wei Huang Hon‐Tsen Yu 《Molecular ecology resources》2002,2(1):49-50
Japanese anchovy (Engraulis japonica) is a migratory marine fish of high economic significance in Taiwan. The adult Japanese anchovies migrate from the East China sea to spawn in coastal waters of Taiwan; the larvae then drift back to the East China Sea to complete their life cycle. We developed six highly polymorphic microsatellites for E. Japonica (expected heterozygosity ranging from 0.751 to 0.971) and these microsatellites can be used as genetic markers for identifying stocks to establish regulations in fishing management. Moreover, the markers will be useful in inferring the stock origins and migration routes in the future. 相似文献
992.
Jay Ram Lamichhane Yann Devos Hugh J. Beckie Micheal D. K. Owen Pascal Tillie Antoine Messéan 《Critical reviews in biotechnology》2017,37(4):459-475
Conventionally bred (CHT) and genetically modified herbicide-tolerant (GMHT) crops have changed weed management practices and made an important contribution to the global production of some commodity crops. However, a concern is that farm management practices associated with the cultivation of herbicide-tolerant (HT) crops further deplete farmland biodiversity and accelerate the evolution of herbicide-resistant (HR) weeds. Diversification in crop systems and weed management practices can enhance farmland biodiversity, and reduce the risk of weeds evolving herbicide resistance. Therefore, HT crops are most effective and sustainable as a component of an integrated weed management (IWM) system. IWM advocates the use of multiple effective strategies or tactics to manage weed populations in a manner that is economically and environmentally sound. In practice, however, the potential benefits of IWM with HT crops are seldom realized because a wide range of technical and socio-economic factors hamper the transition to IWM. Here, we discuss the major factors that limit the integration of HT crops and their associated farm management practices in IWM systems. Based on the experience gained in countries where CHT or GMHT crops are widely grown and the increased familiarity with their management, we propose five actions to facilitate the integration of HT crops in IWM systems within the European Union. 相似文献
993.
Papa Ibnou Ndiaye Yann Quilichini Adji Mama Marigo Cheikh Tidiane Bâ Vasyl V. Tkach Bernard Marchand 《Tissue & cell》2017,49(1):15-21
The mature spermatozoon of Sclerodistomum italicum is filiform, tapered at both ends and shows the following features: 2 axonemes of the 9 + “1” pattern of the Trepaxonemata, mitochondrion, nucleus and parallel cortical microtubules. The specific features of the spermatozoon of S. italicum include the simultaneous presence of two types of extramembranous ornamentations, the presence of short cortical microtubules in the anterior part of the spermatozoon and the presence of only one bundle of cortical microtubules in the median part of the spermatozoon. Thus far these structures are known only in the Hemiuroidea. The presence of filamentous ornamentation in the anterior extremity of the spermatozoon has not previously been described in the Sclerodistomidae. Similar to spermatozoa of other hemiuroideans, S. italicum lack spine-like bodies described in spermatozoa of many digenean taxa. The posterior extremity of the spermatozoon exhibits the same ultrastructural characteristics typical of the Hemiuroidea. 相似文献
994.
Humans are constantly exposed to mycotoxins (e.g. aflatoxins, ochratoxins), mainly via food intake of plant and animal origin. The health risks stemming from mycotoxins may result from their toxicity, in particular their carcinogenicity. In order to prevent these risks, the International Agency for Research on Cancer (IARC) in Lyon (France)—through its IARC Monographs programme—has performed the carcinogenic hazard assessment of some mycotoxins in humans, on the basis of epidemiological data, studies of cancer in experimental animals and mechanistic studies. The present article summarizes the carcinogenic hazard assessments of those mycotoxins, especially aflatoxins (aflatoxin B1, B2, G1, G2 and M1), fumonisins (fumonisin B1 and B2) and ochratoxin A (OTA). New information regarding the genotoxicity of OTA (formation of OTA-DNA adducts), the role of OTA in oxidative stress and the identification of epigenetic factors involved in OTA carcinogenesis–should they indeed provide strong evidence that OTA carcinogenicity is mediated by a mechanism that also operates in humans–could lead to the reclassification of OTA. 相似文献
995.
One‐pot synthesis of carbon dots using two different acids and their respective unique photoluminescence property 下载免费PDF全文
Elaine Loi Roy Wei Chao Ng Melissa May Fung Chang Jessica Fung Yee Fong Yann Huey Ng Sing Muk Ng 《Luminescence》2017,32(1):114-118
Carbon dots, a new class of nanomaterial with unique optical property and have great potential in various applications. This work demonstrated the possibility of tuning the emission wavelength of carbon dots by simply changing the acid type used during synthesis. In particular, sulfuric and phosphoric acids and a mixture of the two were used to carbonize the same starting precursor, sucrose. This resulted in the isolation of carbon dots with blue (440 nm) and green (515 nm) emission. Interestingly, the use of an acid mixture at various ratios did not shift the initial emission profile, but did obviously alter the fluorescence efficiency of the peaks. This clearly showed that acid type can be used as an alternative tool to produce carbon dots that have different emissions using the same starting precursor. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
996.
Clotilde Jumelle Thibaud Garcin Anne Sophie Gauthier Yaël Glasson Aurélien Bernard Yann Gavet Jacques Klossa Zhiguo He Sophie Acquart Philippe Gain Gilles Thuret 《Cell and tissue banking》2017,18(2):185-191
The posterior side of the cornea is covered by the endothelial monolayer, which governs corneal transparency but cannot proliferate. Determination of endothelial cell density (ECD) is therefore the minimal and mandatory quality control in all eye banks. It avoids primary graft failures caused by endothelial insufficiency, and allows allocation of corneas to surgical techniques requiring different numbers of endothelial cells (ECs). Corneas stored in organ culture (17% of grafts worldwide), are characterized by heavy stromal swelling and numerous deep endothelial folds, up to 200 µm high. During microscopic en face observation, flat surfaces are thus exceptional and EC counting is biased by parallax errors, resulting in overestimated eye bank ECD (ebECD). We used a motorized transmitted light microscope to acquire Z-stacks of images every 10 µm, and processed them to reconstruct the 3D surface of the folded endothelium. This method (3D-ECD) takes into account the local point-by-point slope in order to correct ECD. On a set of 30 corneas, we compared 3D-ECD and ebECD determined on five identical zones at the center of the cornea. 3D reconstruction allowed us to visualize twice as many cells, and ebECD was 8.1 ± 4.5% (95%CI 6.4–9.7) higher than 3D-ECD, with 1744 ± 488 versus 1606 ± 473 cells/mm2. 3D counting makes it possible to increase cell sampling and to correct overestimation by the conventional en face counting still routinely performed in eye banks. 相似文献
997.
998.
Guérardel Y Leleu D Coppin A Liénard L Slomianny C Strecker G Ball S Tomavo S 《Microbes and infection / Institut Pasteur》2005,7(1):41-48
The obligate intracellular protozoan Toxoplasma gondii belongs to the phylum Apicomplexa, which is composed of numerous parasites causing major diseases such as malaria, toxoplasmosis and coccidiosis. The life cycle of T. gondii involves developmental processes from one stage to another with both asexual and sexual parasitic forms. Throughout their life cycle, some apicomplexan parasites accumulate a crystalline storage polysaccharide analogous to amylopectin within the cytoplasm. In T. gondii, both the slowly dividing encysted bradyzoites and the sporozoites of the sexual stage contain a high number of amylopectin granules (AG), while the rapidly replicating tachyzoites are devoid of amylopectin. It is thought that this storage polysaccharide may represent an energy reserve that could fuel the transition from one developmental stage to another one. At present, by comparison to glycogen and plant starch, little is known about the biosynthesis, structure and biological functions of amylopectin in T. gondii. Here, we describe an in vitro system allowing the production and purification of a large amount of amylopectin, which has been subjected to detailed biochemical and structural analyses. Our data indicate that T. gondii synthesizes a genuine amylopectin following changes in the environmental conditions and that this storage polysaccharide differs from glycogen and starch in terms of glucan chain length. 相似文献
999.
1000.
Functional compartmentalization of dendrites is thought to underlie afferent-specific integration of neural activity in laminar brain structures. Here we show that in the lateral nucleus of the amygdala (LA), an area lacking apparent laminar organization, thalamic and cortical afferents converge on the same dendrites, contacting neighboring but morphologically and functionally distinct spine types. Large spines contacted by thalamic afferents exhibited larger Ca(2+) transients during action potential backpropagation than did small spines contacted by cortical afferents. Accordingly, induction of Hebbian plasticity, dependent on postsynaptic spikes, was restricted to thalamic afferents. This synapse-specific effect involved activation of R-type voltage-dependent Ca(2+) channels preferentially located at thalamic inputs. These results indicate that afferent-specific mechanisms of postsynaptic, associative Hebbian plasticity in LA projection neurons depend on local, spine-specific morphological and molecular properties, rather than global differences between dendritic compartments. 相似文献