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51.
The presence of excessive amounts of heavy metals such as arsenic in the environment is a problem in many parts of the world. Many countries e.g., Bangladesh are already severely affected by arsenic contamination of soil and groundwater. Phytoaccumulation is a method in which plants are used to uptake heavy metals from soil. The genus Brassica has many species that can efficiently accumulate arsenic. Despite many studies on phytoaccumulation, little is known about the genetics of phytoaccumulation of Brassica. This study investigated the genetic effect on phytoaccumulation of arsenic in Brassica juncea L. and attempted to identify any morphological trait(s) for phytoaccumulation. Two cultivars of B. juncea namely, B. juncea cv. Rai and B. juncea cv. BARI-11 were chosen as parents for the study. A set of their morphological characteristics were selected to evaluate their potential as marker(s) for phytoaccumulation. A single concentration, 15 ppm of arsenic was used to study the genetic effect on phytoaccumulation using quantitative genetics. The results revealed that phytoaccumulation of arsenic (by the root and shoot systems) is heritable in the broad sense and polygenic in nature. The stem diameter was also found to be heritable in the broad sense and path analysis indicated that it has a significant direct effect on the shoot uptake. It is concluded that phytoaccumulation of arsenic in B. juncea (cvs. Rai and BARI-11) is a genetic phenomenon and stem diameter may be a potential marker of phytoaccumulation of arsenic in B. juncea (cvs. Rai and BARI-11). 相似文献
52.
The Sheanut tree (Vitellaria paradoxa Gaertn.), a multi-purpose species highly valued for the oil obtained from its seeds, is commonly maintained in the semi-arid
parklands of sub-Saharan West Africa. An inventory in the West Gonja District, Northern Region, Ghana, revealed that on intensively
farmed land this species constituted 79.7 ± 7.2% (Basal area = 2.19 ± 0.64 m2 ha−1) of the woody biomass, on low intensity farmland 84.2 ± 10.0% (2.16 ± 0.57 m2 ha−1) and only 10.2 ± 3.3% (0.92 ± 0.23 m2 ha−1) in unmanaged woodland, with similar environmental characteristics. No significant differences were found between total Sheanut
tree densities on different land use intensities, although as a proportion of all trees surveyed, large trees were more common
on farmed land. Participatory surveys revealed that these populations are a direct result of anthropic selection as local
farmers eliminate unwanted woody species on farmland, leaving only those Sheanut trees that meet criteria based on spacing,
size, growth, health, age and yield. Characteristics that could affect population dynamics during traditional management and
harvesting including short viability seeds and cryptogeal germination are also discussed with reference to unconscious selection.
Tree improvement is currently constrained, as true to type varieties are difficult to propagate. It is proposed that Sheanut
trees on farmland are semi-domesticated having been subject to long-term anthropic selection during cycles of traditional
fallow and crop cultivation.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
53.
Mirja Kaizer Ahmmed Shuva Bhowmik Stephen G. Giteru Md. Nazmul Hasan Zilani Parise Adadi Shikder Saiful Islam Osman N. Kanwugu Monjurul Haq Fatema Ahmmed Charlene Cheuk Wing Ng Yau Sang Chan Md. Asadujjaman Gabriel Hoi Huen Chan Ryno Naude Alaa El-Din Ahmed Bekhit Tzi Bun Ng Jack Ho Wong 《Marine drugs》2022,20(7)
Lectins are a unique group of nonimmune carbohydrate-binding proteins or glycoproteins that exhibit specific and reversible carbohydrate-binding activity in a non-catalytic manner. Lectins have diverse sources and are classified according to their origins, such as plant lectins, animal lectins, and fish lectins. Marine organisms including fish, crustaceans, and mollusks produce a myriad of lectins, including rhamnose binding lectins (RBL), fucose-binding lectins (FTL), mannose-binding lectin, galectins, galactose binding lectins, and C-type lectins. The widely used method of extracting lectins from marine samples is a simple two-step process employing a polar salt solution and purification by column chromatography. Lectins exert several immunomodulatory functions, including pathogen recognition, inflammatory reactions, participating in various hemocyte functions (e.g., agglutination), phagocytic reactions, among others. Lectins can also control cell proliferation, protein folding, RNA splicing, and trafficking of molecules. Due to their reported biological and pharmaceutical activities, lectins have attracted the attention of scientists and industries (i.e., food, biomedical, and pharmaceutical industries). Therefore, this review aims to update current information on lectins from marine organisms, their characterization, extraction, and biofunctionalities. 相似文献
54.
The benefits provided by underutilised fruit tree species such as baobab (Adansonia digitata L.) in combating increasing malnutrition and poverty become more apparent as awareness grows regarding concerns of climate
change and food security. Due to its multiple uses, its high nutritional and medicinal value, drought tolerance and relatively
easy cultivation, baobab has been identified as one of the most important edible forest trees to be conserved, domesticated
and valued in Africa. In order to contribute towards the cultivation of the species, suitability of sites in Africa and worldwide
was evaluated for potential cultivation using species’ locality data and spatial environmental data in MAXENT modelling framework.
A total of 450 geo-referenced records of the baobab tree were assembled from herbarium records, commercial firm’s databases
and fieldwork for modelling site suitability for global cultivation of the baobab tree. Climatic and topographic data were
acquired from the Worldclim data while soil data was obtained from the Harmonized World Soil Database. MAXENT was found to
be a successful modelling method for studying cultivation potential. The main variables that contributed towards predicting
baobab’s global cultivation potential were annual precipitation and temperature seasonality. Results suggest that baobab tree
could be widely cultivated in most countries in southern Africa and in the Sudano-Sahelian zone of West Africa from Senegal
to Sudan. Angola and Somalia were found to be highly suitable for cultivating baobab in Africa. Model suggests, India, where
the baobab tree already exists and is used, to be the most suitable country for baobab cultivation outside Africa. North-west
Australia, Madagascar, north-east Brazil and Mexico resulted to be other suitable places for cultivating the tree species.
Although it is recommended model results be validated with in situ seedling experiments, there seems to be a great potential
for the cultivation of this species globally. 相似文献
55.
Akhtar K. P. Ryu K. H. Saleem M. Y. Asghar M. Jamil F. F. Haq M. A. Khan I. A. 《植物病害和植物保护杂志》2008,115(1):2-3
Journal of Plant Diseases and Protection - Infection of tomato in Faisalabad, Pakistan with subgroup IA strain of Cucumber mosaic virus (CMV) is reported for the first time. The virus was detected... 相似文献
56.
Thirty progenies of mungbean were produced by crossing 10 true-breeding genotypes with three testers (NM 92, 6601, and their
F1) in a Triple Test cross (TTC) fashion and evaluated with parents in the kharif (July-October) and spring/summer (March-June)
seasons. The data on parents and F1s were analysed for pod clusters on main stem, pod clusters on branches, node of the first peduncle, nodes on main stem and
average internode length to detect epistasis and estimate additive and dominance components of genetic variation. Epistasis
was observed for node of the first peduncle and nodes on main stem in the kharif season. Partitioning of total epistasis revealed
that both additive × additive (i type), and additive × dominance, and dominance × dominance (j and l types) interactions were
significant with prevalent influence of i type interactions on these traits. Both additive and dominance components of genetic
variation were significant for all those traits not significantly influenced by epistasis in either or both seasons. The additive
component was predominant for pod clusters on main stem, pod clusters on branches and average internode length in the kharif
season, and for the node of the first peduncle and nodes on main stem in spring/summer season whereas dominance component
was important for pod clusters on main stem, pod clusters on branches, and average internode length in spring/summer season.
These results suggested that particular generation of segregating population and specific breeding method for selection might
be adopted in each season for the improvement of these traits in mungbean.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
57.
D. P. Cherukuri S. K. Gupta A. Charpe S. Koul K. V. Prabhu R. B. Singh Q. M. R. Haq S. V. S. Chauhan W.E. Weber 《Plant Breeding》2003,122(3):204-208
The leaf rust resistance gene Lr19, transferred from Agropyron elongatum into wheat (Triticum aestivum L.) imparts resistance to all pathotypes of leaf rust (Puccinia recondita f.sp. tritici) in South‐east Asia. A segregating F2 population from a cross between the leaf rust resistant parent ‘HW 2046’ carrying Lr19 and a susceptible parent ‘Agra Local’ was screened in the phytotron against a virulent pathotype 77‐5 of leaf rust with the objective of identifying the molecular markers linked to Lr19. The gene was first tagged with a randomly amplified polymorphic DNA (RAPD) marker S73728. The RAPD marker linked to the gene Lr19 which mapped at 6.4 ± 0.035 cM distance, was converted to a sequence characterized amplified region (SCAR) marker. The SCAR marker (SCS73719) was specific to Lr19 and was not amplified in the near‐isogenic lines (NILs) carrying other equally effective alien genes Lr9, Lr28 and Lr32 enabling breeders to pyramid Lr19 with these genes. 相似文献
58.
Summary Amphidiploidy was induced by colchicine treatment of cuttings from the F1 interspecific hybrid Phaseolus vulgaris L. x Ph. coccineus L.. Pollen stainability rose from about 50% in the raw amphidiploid to 76% in some C5 individuals; similar improvement in seed fertility was also observed. It is suggested that both genic and chromosomal factors are implicated in the control of fertility in the amphidiploid.The amphidiploid is apparently unable to cross successfully with either parental species; difference in ploidy level is apparently an effective isolating mechanism between the amphidiploid and its parents. 相似文献
59.
With the aim of helping to select superior planting material for drought characteristics, baobab seedlings from two countries, one in western and one in south-eastern Africa, were grown in a greenhouse and their growth and morphology were studied. Seedlings were grown for 18 weeks and several morphological characteristics (length, diameter and dry weights of different plant parts, number of leaves, stomatal density, among others) were recorded at different harvesting times. Biomass allocation changed with time: seedlings invested more in fine roots and leaves in the beginning of their growth while later they invested more in the development of the taproot. In general, at any harvest time, seedlings from Malawi were larger; but seedlings from Mali had higher relative growth rates and a faster ontogeny. Seedlings from Mali had shorter hypocotyls, their stems were thicker, they had fewer leaves, lower leaf area ratios and, in general, they had a higher stomatal density than those from Malawi. Significant differences between provenances within one country could also be observed. In general, seedlings from drier provenances were smaller overall, they had fewer leaves, higher taproot water content and stomatal density, characteristics often related to drought adaptation. Seedlings from drier provenances also invested more in their taproot, a key organ for baobab seedling survival. Although our seedlings were only grown under optimal conditions in a greenhouse, results from this study indicate that there is a great variation in baobab seedling growth, biomass allocation to plant parts and morphology, which gives opportunities to select high quality planting material. 相似文献
60.
Vista Budiariati Ratih Rinendyaputri Ariyani Noviantari Noer Muhammad Dliyaul Haq Dwi Budiono Diah Nugrahani Pristihadi Berry Juliandi Mokhamad Fahrudin Arief Boediono 《Journal of veterinary science (Suw?n-si, Korea)》2021,22(6)
BackgroundConditioned medium is the medium obtained from certain cultured cells and contained secretome from the cells. The secretome, which can be in the form of growth factors, cytokines, exosomes, or other proteins secreted by the cells, can induce the differentiation of cells that still have pluripotent or multipotent properties.ObjectivesThis study examined the effects of conditioned medium derived from E17 rat brain cells on cells with pluripotent properties.MethodsThe conditioned medium used in this study originated from E17 rat brain cells. The CM was used to induce the differentiation of primary colonies of mice blastocysts. Primary colonies were stained with alkaline phosphatase to analyze the pluripotency. The morphological changes in the colonies were examined, and the colonies were stained with GFAP and Neu-N markers on days two and seven after adding the conditioned medium.ResultsThe conditioned medium could differentiate the primary colony, beginning with the formation of embryoid-body-like structure; round GFAP positive cells were identified. Finally, neuron-like cells testing positive for Neu-N were observed on the seventh day after adding the conditioned medium.ConclusionsConditioned medium from different species, in this case, E17 rat brain cells, induced and promoted the differentiation of the primary colony from mice blastocysts into neuron-like cells. The addition of CM mediated neurite growth in the differentiation process. 相似文献