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41.
Tetrasomic plants with two additional small chromosomes were identified, with a frequency about 2.5%, in the trisomic pea
line TRUST-R, which normally contains one extra chromosome covering a sporophyte lethal in the regular chromosome set. As
compared to trisomics, tetrasomics exhibited an enhanced expression of the traits resulting from extra chromosome addition:
slow growth, enlarged bracts, shortened peduncles, wavy leaflets and stipulae. They were almost sterile, their pollen contained
a variable proportion of empty grains and some anomalously large, small or deformed grains. In metaphase I, two extra chromosomes
did not form a stable bivalent and only in some cases were situated close to each other. In anaphase I, the extra chromosomes
migrated independently to either pole or retarded in the equatorial plain, the same was observed for chromatids in anaphase
II. This retardation resulted in anomalous cytokinesis, so that triads, dyads and half-divided or non-divided monads appeared.
The retarded extra chromosomes may form small extra nuclei either included into one of the microspores or forming a separate
miniature cell; in this way tetrasomics may eliminate extra chromosomes. One of the tetrasomics analysed formed an exceptionally
high proportion of microspore pentads. In the regluar TRUST-R trisomics, the sole extra chromosome retarded in the equatorial
plain in anaphases I and II. The retardation in anaphase II often makes cytokinesis in trisomics (in general more regular
than in tetrasomic) to proceed in two steps: at first cell wall formation separates a pollen mother cell into two dyads and
then each of them into two microspores. 相似文献
42.
Chandra-Hioe Maria V. Elvira Jenny Arcot Jayashree 《Plant foods for human nutrition (Dordrecht, Netherlands)》2019,74(1):34-39
Plant Foods for Human Nutrition - Lutein is a xanthophyll, a bioactive phytochemical that presents itself as colourful pigments in plants. Australian sweet lupin flour has been... 相似文献
43.
Elvira Sereda Theo Blick Wolfgang H.O. Dorow Volkmar Wolters Klaus Birkhofer 《Pedobiologia》2012,55(5):241-245
Describing the biotic and abiotic processes that are responsible for the formation of spatial patterns in predators and their prey is crucial for improving our understanding of food–web interactions. We studied the spatial distribution of four abundant spider species and three common groups of epedaphic Collembola prey in a beech-dominated (Fagus sylvatica) forest floor habitat and related the observed patterns to environmental heterogeneity, overall predator activity (all ground beetles and spiders) and prey availability (all Collembola) at the local scale. Spiders and epedaphic Collembola were sampled over 392 days in a spatially explicit design based on a regular grid of 25 pitfall traps (inter-trap distance 100 m). Environmental heterogeneity was characterized by cover of moss and litter as well as the amount of dead wood at each trap location. We first used the index of dispersion to characterize the spatial distribution of spider species and Collembola and then related the observed patterns to environmental heterogeneity, predator and prey availability while testing for spatial autocorrelation within the same models. All taxa were significantly more aggregated than expected from the assumption of random distribution. The distribution of spider species was positively (Coelotes terrestris) or negatively (Tenuiphantes zimmermanni and Tapinocyba insecta) related to the cover of moss and negatively related to litter cover (C. terrestris) or the local availability of prey (T. insecta). The distribution of Collembola was negatively related to local litter cover (Lepidocyrtus spp.) and positively related to the amount of medium deadwood pieces (all other Entomobryidae). Our study suggests that none of the spider species preferred areas of low overall predator activity density. Moreover, it does not indicate association of spider species to prey-rich areas at the analyzed scale of 100 m. It further highlights the importance of environmental heterogeneity, as different habitat properties differentially affected the local activity density of spiders and Collembola and thus considerably contributed to the understanding of distribution patterns. 相似文献
44.
Iatrogenic proximal urethral obstruction after inadvertent prostatectomy during bilateral perineal herniorrhaphy in a dog 下载免费PDF全文
Sereda C Fowler D Shmon C 《The Canadian veterinary journal. La revue veterinaire canadienne》2002,43(4):288-290
Proximal urethral obstruction was diagnosed 2 days after bilateral perineal herniorrhaphy in a 12-year-old male Pomeranian-cross dog. The obstruction was caused by ligation of the proximal urethra during resection of a presumed paraprostatic cyst. Surgical repair involved reconstruction of the urethra and bladder wall, but urinary incontinence persisted. 相似文献
45.
Frias J Song YS Martínez-Villaluenga C González de Mejia E Vidal-Valverde C 《Journal of agricultural and food chemistry》2008,56(1):99-105
Food allergy has become a public health problem that continues to challenge both the public and the food industry. The objective of this research was the detection and quantification of the major human allergenic soy proteins and to study the reduction in immunoreactivity and improvement of amino acid content after fermentation of soybean flour. Fermentation was carried out in the solid state of cracked seeds inoculated with Aspergillus oryzae, Rhizopus oryzae, and Bacillus subtilis and in the liquid state of milled soybean flours fermented naturally by microorganisms present only in the seeds or by inoculation with Lactobacillus plantarum. ELISA and Western blot were used to quantify IgE antibody response, and HPLC was used to identify and quantify total amino acids. L. plantarum fermented soy flour showed the highest reduction in IgE immunoreactivity (96-99%) depending upon the sensitivity of the plasma used. Among the solid fermented products, the lowest reduction in immunoreactivity was obtained when mold strains, R. oryzae and A. oryzae, were used (66 and 68%, respectively, for human plasma 97.5 kUA/L). Among the solid fermented products, those inoculated with B. subtilis yielded a 81 and 86% reduction in immunoreactivity against both human plasma 97.5 IgE kUA/L and human pooled plasma samples, respectively. When soybean was subjected to liquid fermentation, most of the total amino acids increased significantly ( p < or = 0.05). In solid fermentation with R. oryzae, only Ala and Thr content improved. Fermentation can decrease soy immunoreactivity, and there is potential of developing nutritious hypoallergenic soy products. 相似文献
46.
A greenhouse experiment was carried out during the spring–summer 2009 to test the hypotheses that: (1) arbuscular‐mycorrhizal (AM) inoculation with a biofertilizer containing Glomus intraradices gives an advantage to overcome alkalinity problems, (2) mineral fertilization is more detrimental to AM development than organic fertilization on an equivalent nutrient basis. Arbuscular mycorrhizal (AM) and non‐AM of zucchini (Cucurbita pepo L.) plants were grown in sand culture with two pH levels in the nutrient solution (6.0 or 8.1) and two fertilization regimes (organic or mineral). The high‐pH nutrient solution had the same basic composition as the low‐pH solution, plus an additional 10 mM NaHCO3 and 0.5 g L–1 CaCO3. Increasing the concentration of NaHCO3 from 0 to 10 mM in the nutrient solution significantly decreased yield, plant growth, SPAD index, net assimilation of CO2 (ACO2), N, P, Ca, Mg, Fe, Mn, and Zn concentration in leaf tissue. The +AM plants under alkaline conditions had higher total, marketable yield and total biomass compared to –AM plants. The higher yield and biomass production in +AM plants seems to be related to the capacity of maintaining higher SPAD index, net ACO2, and to a better nutritional status (high P, K, Fe, Mn, and Zn and low Na accumulation) in response to bicarbonate stress with respect to –AM plants. The percentage root colonization was significantly higher in organic‐fertilized (35.7%) than in mineral‐fertilized plants (11.7%). Even though the AM root colonization was higher in organic‐fertilized plants, the highest yield and biomass production were observed in mineral‐fertilized plants due to the better nutritional status (higher N, P, Ca, and Mg), higher leaf area, SPAD index, and ACO2. 相似文献
47.
Clara Medeira Virgínia Quartin Isabel Maia Inês Diniz Ma Céu Matos José Nobre Semedo Paula Scotti-Campos José C. Ramalho Isabel P. Pais Paula Ramos Elvira Melo António E. Leit?o Alfredo Cravador 《European journal of plant pathology / European Foundation for Plant Pathology》2012,134(1):145-159
The decline of cork oak (Quercus suber) stands in Iberian Peninsula is associated with infection by Phytophthora cinnamomi. Most Phytophthora species secrete elicitins, which can enhance defence reactions against some pathogens. Here cytological and physiological effects of the elicitins cryptogein and capsicein on cork oak root infection by P. cinnamomi were evaluated. The progression of the pathogen in root tissue and its effects on total fatty acid (TFA) composition of roots and leaves were analysed in seedlings. Net photosynthesis (P n ), stomatal conductance (g s ), chlorophyll a fluorescence measurements (quantum yield of linear electron transport ? e , photochemical quenching q P, non-photochemical quenching NPQ) and carotenoid determinations were carried out in well established (4?months) plants. In elicitin-treated roots, 2?days after inoculation, the pathogen which presented loss of viability and membrane degradation was mainly restricted to the intercellular spaces of the cortical parenchyma, and did not reach the vascular cylinder. Electron dense materials accumulated in the intercellular spaces of the cortex next to disorganized hyphae, suggested to be related with defence reactions. Cryptogein (or its interaction with P. cinnamomi) induced enhanced lipid synthesis in leaves, which may contribute to preserve membrane stability. P. cinnamomi decreased P n , g s , ? e , and q P, whereas elicitin-treated plants displayed values similar to controls. Overall, the results indicated a resistance response of cork oak against this oomycete, induced by the elicitins. 相似文献
48.
Gómez-Couso H Méndez-Hermida F Castro-Hermida JA Ares-Mazás E 《Veterinary parasitology》2005,133(1):13-18
Giardia cyst contamination of mussels (Mytilus galloprovincialis), raw and treated waste waters and water from rivers that flow into four Galician estuaries (NW Spain), where bivalve molluscs are cultured for human consumption, was studied. The high prevalence of contamination in mussels (41.8%, n=184), raw waste water (90.9%, n=11), treated waste water (87.5%, n=16) and in samples of river water (85.7%, n=7), with cyst counts of 9.8-1800.0, 7.0-2541.0 and 1.0-29.3 cysts l(-1), respectively, illustrate the wide distribution of this enteropathogen in the environment and the potential risk to public health associated with the consumption of raw or undercooking bivalves and use of these estuaries for recreational purposes. 相似文献
49.
This paper assesses the guanta (Cuniculus paca) as a source of edible bushmeat under the frame of Buen Vivir, an Ecuadorian official paradigm that postulates, among other things, a single harmonized relationship between wildlife species and society. Three econometric models are estimated using a 2014 survey of Flavio Alfaro (Manabí, Ecuador) hunters. The results showed that estimates of private value fail to reflect the intrinsic social value of guanta, as they only take into account conventional production costs, ignoring other subjective features such as the mix of cultural factors as an unequivocal reflection of the ancestral ethos distinctive of communities living under subsistence conditions. Some important aspects are proposed for consideration when preparing public policy toward the sustainable management of guanta and other closely related species. 相似文献
50.
Barbara De Lucia Lorenzo Vecchietti Simona Rinaldi Carlos Mario Rivera Alessandra Trinchera Elvira Rea 《Journal of plant nutrition》2013,36(6):863-876
The objective of this work was to study the use of four composts, obtained by agro-industrial, urban and green wastes, as growing media components on Rosmarinus officinalis L. Substrates were obtained by mixing each compost with peat in different proportions. Main physical and chemical characteristics of prepared substrates have been compared and, at the end of growing cycle, the biometric survey on main growing parameters and plant nutritional status was performed. The obtained results showed that substrates with 30% compost have main physical and chemical parameters comparable with those of the control. Best quality plants have been obtained substituting peat with 30% of compost, except with the olive mill compost. At the end, the green pruning compost can be recommended as growing media component (up to 50%) for the growth of Rosmarinus officinalis L., being able to determine high quality plants, together with an implemented plant nutrient efficiency. 相似文献