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21.
A. Karami A. Christianus Z. Ishak S. C. Courtenay M. A. Syed M. Noor Azlina H. Noorshinah 《Aquaculture International》2010,18(5):851-858
Triploid African catfish (Clarias gariepinus) produced through cold shock 3 min post fertilization were compared to diploid offspring of the same parentage at 66 days
of age. Triploid fish were significantly shorter (11%) and weighed less (18%) than diploids but showed no significant difference
in mortality or cannibalism, which can be an important source of losses under aquaculture conditions. Erythrocytes of triploid
fish were more oval shaped than the normal spherical shape of diploid erythrocytes, were significantly larger (38%) and had
nuclei that were significantly larger (25%) than observed in diploid fish. Erythrocyte morphological characteristics show
potential as an indicator for the detection of triploidy in African catfish. 相似文献
22.
Azam Ali Vijay Baheti Jiri Militky Zaman Khan Syed Qummer Zia Gilani 《Fibers and Polymers》2018,19(3):607-619
The present work described the development of multifunctional, electrically conductive and durable fabrics by coating of silver and copper particles using a dipping-drying method. The particles were directly grown on fabric structure to form electrically conductive fibers. Particles were found to fill the spaces between the microfibers, and were stacked together to form networks with high electrical conductivity. The electrically conductive fabrics showed low resistance with high stretch ability. The utility of conductive fabrics was analyzed for electromagnetic shielding ability over frequency range of 30 MHz to 1.5 GHz. The EMI shielding was found to increase with increase in concentration of copper and silver particles. Furthermore, the heating performance of the copper and silver coated fabric was studied through measuring the change in temperature at the surface of the fabric while applying a voltage difference across the fabric. The maximum temperature (119°C for silver and 112°C for copper) were obtained when the applied voltage was 10 V. Moreover, the role of deposited particles on antibacterial properties was examined against pathogenic bacteria such as Staphylococcus aureus and Escherichia coli. At the end, the durability of coated fabrics was examined against several washing cycles. The fabrics showed good retention of the particles, proved by small loss in the conductivity of the material after washing. 相似文献
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25.
Iqra Javid Mahroze Fatima Syed Zakir Hussain Shah Muhammad Afzal 《Aquaculture Nutrition》2021,27(1):217-224
The effect of organic acids (OA) and dicalcium phosphate (Pi) supplementation in the feed of Labeo rohita fingerlings was studied by formulating seven practical diets, designed as D1 with no feed additives {dicalcium phosphorus (Pi) and organic acid (OA) blend} while, D2, D3, D4 and D5 were supplemented with Pi at the graded levels of 5, 10, 15 and 20 g/kg, respectively, whereas D6 and D7 contained blend of OA at 15 and 30 g/kg, respectively. The diet supplemented with OA blend exhibited increase (p < .05) in growth of L. rohita fingerlings compared with the diet supplemented with Pi. The OA supplementation at both levels showed significant improvement in nutrients digestibility and minerals absorption in fingerlings. Moreover, in case of muscle proximate composition, crude fat (CF) and crude protein (CP) were increased (p < .05) with the inclusion of OA blend in the diet while crude ash (CA) was improved by Pi supplementation. Additionally, digestive enzyme activities were not affected (p ? .05) by OA blend supplementation while increased activities were observed in the fingerlings fed with Pi diet. Consequently, supplementation of OA blend in the diet improved the growth performance and nutrient status while Pi enhanced digestive enzyme activities of L. rohita fingerlings. 相似文献
26.
Gyula Vida Mariann Gál Andrea Uhrin Ottó Veisz Naeem Hasan Syed Andrew J. Flavell Zhulin Wang Zoltán Bedő 《Euphytica》2009,170(1-2):67-76
The resistance genes Lr9, Lr24, Lr25, Lr29, Lr35 and Lr37, which were not previously utilised in Hungary, have been incorporated into four Martonvásár winter wheat cultivars using marker-assisted selection with PCR-based markers. In the course of a backcross programme, the genes were transferred into Martonvásár wheat varieties and various BC generations were produced. Work aimed at pyramiding resistance genes is currently underway in Martonvásár, and plants containing the gene combinations Lr9 + Lr24, Lr9 + Lr25 and Lr9 + Lr29 are now available. From the BC2F4 generation of the ‘Mv Emma’*3/’R.L.6010’ combination (‘R.L.6010’ is the donor of the Lr9 gene) 287 lines were tested for leaf rust resistance in an artificially inoculated nursery. A co-dominant primer combination was designed to identify both resistant and susceptible offsprings. The results of resistance tests and molecular marker detection agreed in most cases. Designated leaf rust resistance genes were identified with molecular markers in wheat varieties and breeding lines. The Lr26 and Lr34 resistance genes occur frequently in the Martonvásár gene pool, and the presence of the Lr37 gene has also been detected in a number of Hungarian genotypes. 相似文献
27.
Shahid Iqbal Awan Muhammad Shahzad Ahmed Jehanzeb Farooq Syed Dilnawaz Ahmad Muhammad Ilyas Asad Hussain Shah Muhammad Fareed Khan Sardar Ali Lutful Hasan 《Frontiers of Agriculture in China》2011,5(4):486-496
An experiment was conducted to access the genetic variability among early vigour and quantitative traits under limited moisture
in F2 generation of a 5 × 5 diallel cross of bread wheat. The results indicated that there was significant genotypic variation
among the genotypes. Additive dominance model revealed full fitness of the data for RL, DSW, FRW, DRW, spike length, and 1000-grain
weight but was partially fit for SL, FSW, R/S, tillers per seedling, plant height, tillers per plant, spikelets per spike,
and grain yield per plant. The partially adequate models for these plant characters might be due to the presence of non-allelic
interaction, linkage, and non-independent distribution of the genes in the parents. Additive genes coupled with moderate to
high narrow sense heritability were involved in the heritage of all the traits, which indicated a higher scope of selection
in early generations. 相似文献
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Morteza Kamrani Yaser Hoseini Asgar Ebadollahi 《Archives of Agronomy and Soil Science》2018,64(1):38-45
Heat stress is a major environmental stress limiting wheat productivity in most cereal growing areas of the world. The objective of this study was to evaluate heat stress tolerance in durum wheat (Triticum turgidum var. durum) genotypes. For this purpose, 45 genotypes were grown during two growing seasons (2012–2013 and 2013–2014) under non-stress (normal sowing) and heat-stress (late sowing) conditions. The heat tolerance indices were calculated based on grain yield under normal sowing (Yp) and late sowing (Ys) conditions. Results of combined analysis of variance showed the significant influences of heat stress on grain yield as well as significant differences among genotypes for grain yield and the indices. Results of correlation coefficients and multivariate analyses revealed that the stress tolerance index (STI), geometric mean productivity and mean productivity (MP) indices were the most profitable criteria for selection of heat tolerant and high yielding genotypes. Using STI, GMP and MP, the genotypes G29, G41 and G10 were found to be the best genotypes with relatively high yield and suitable for both normal and heat stressed conditions. Based on biplot analysis using Yp, Ys and the indices, it was possible to identify superior genotypes across the conditions. 相似文献
30.
Ashton Lim Suelee Sharifah Nur Munirah Syed Hasan Faradiella Mohd Kusin Ferdaus Mohamat Yusuff Zelina Zaiton Ibrahim 《Water, air, and soil pollution》2017,228(4):158
Phytoremediation using vetiver grass (Vetiveria zizanioides) has been regarded as an effective technique for removing contaminants in polluted water. This study was conducted to assess the removal efficiency of heavy metals (Cu, Fe, Mn, Pb, Zn) using vetiver grass (VG) at different root lengths and densities and to determine metals uptake rate by plant parts (root and shoot) between treatments (low and high concentration). Removal efficiency for heavy metals in water by VG is ranked in the order of Fe>Pb>Cu>Mn>Zn. Results showed that VG was effective in removing all the heavy metals, but removals greatly depend on root length, plant density and metal concentration. Longer root length and higher density showed greater removals of heavy metals due to increased surface area for metal absorption by plant roots. Results also demonstrated significant difference of heavy metals uptake in plant parts at different concentrations indicating that root has high tolerance towards elevated concentration of heavy metals. However, the effects were less significant in plant shoot suggesting that metals uptake were generally higher in root than in shoot. The findings have shown potential of VG in phytoremediation for heavy metals removal in water thus providing significant implication for treatment of metal-contaminated water. 相似文献