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51.
A. Janeczko J. Biesaga‐Kościelniak J. Oklešt'ková M. Filek M. Dziurka G. Szarek‐Łukaszewska J. Kościelniak 《Journal of Agronomy and Crop Science》2010,196(4):311-321
Brassinosteroids are plant steroid hormones important for plant growth and development. They include more then 70 compounds. Their physiological effect and possibilities of practical use are still being investigated. In this study, we evaluated the effects of exogenously applied 24‐epibrassinolide, one of the brassinosteroids, on the grain yield and grain chemical composition (carbohydrates, proteins, fats and minerals) of wheat. Moreover, we analysed the presence of brassinosteroids in newly formed wheat grains after exogenous plant treatment with 24‐epibrassinolide. Experiments were performed in a vegetation hall (plants cultivated in pots) and in the field. The tested regulator was applied via 48 h seed soaking (1 mg·dm?3) or spraying plants at the heading stage (0.25 mg·dm?3). 24‐epibrassinolide increased grain yield in plants growing in the field (by about 20 %), but not in plants cultivated in vegetation hall. Grain chemical composition was altered by 24‐epibrassinolide in wheat growing in the vegetation hall; the content of soluble sugars was higher while that of total fats and calcium was lowered, whereas the starch and soluble protein content was not affected. The effect of the hormone was in these cases dependent on the method of its application. As for plants cultivated in the field, the hormone impact on the amount of carbohydrates, proteins, fats and minerals contained in the grains was rather negligible. In wheat grains, the presence of brassinolide, castasterone and 24‐epicastasterone was found. 24‐Epibrassinolide applied exogenously to plants was not accumulated in newly formed grains. Additionally, significance of ethanol as a hormone solvent is discussed. 相似文献
52.
53.
Łukasz Wolko Wojciech Antkowiak Elżbieta Lenartowicz Jan Bocianowski 《Genetic Resources and Crop Evolution》2010,57(6):801-806
The aim of this study was to identify the group of highly polymorphic microsatellite markers for the identification of six
pear cultivars (P. communis) and two individuals of wild pear (P. pyraster). From among 40 tested SSR markers, 19 were selected to profile genetic diversity in pear genotypes due to high polymorphisms.
These markers showed high heterozygosity levels (0.5–1) and, on average, 6.4 alleles per marker were found. The set of microsatellite
markers employed in this study demonstrated usefulness of microsatellite markers for the identification of pear genotypes.
The examined wild forms were represented in this study by only two individuals of P. pyraster. It can be assumed that these forms were distinctly different from the cultivated pear cultivars. 相似文献
54.
Forlani G Obojska A Berlicki Ł Kafarski P 《Journal of agricultural and food chemistry》2006,54(3):796-802
A series of phosphinothricin derivatives with a modified methyl group, designed on the basis of the crystal structure of the complex formed by the inhibitor and the target enzyme from Salmonella typhimurium, were evaluated as potential inhibitors of plant glutamine synthetase. These compounds were previously shown to be equipotent or slightly weaker inhibitors to the lead compound against the bacterial enzyme. Because of the presence in higher plants of at least two enzyme forms with different subcellular localization and possible separate metabolic functions, plastidial and cytosolic glutamine synthetases were purified to electrophoretic homogeneity from spinach chloroplasts and cultured tobacco cells, respectively. Kinetic analysis confirmed the ability of the phosphinothricin analogues to inhibit both isoenzymes in the micromolar range, with a mechanism of a competitive type with respect to glutamate. Interestingly, some of them exerted a differential effect against either the two plant isoforms, or against the plant versus the bacterial enzyme. 相似文献
55.
The contents of ascorbate, thiols, and phenolic compounds and antioxidative enzyme activity were measured in the apple peel of 56 genotypes after harvest in two vegetation seasons, 2003 and 2004. The main reason of great interest in these bioactive compounds is their well-established physiological role in all living systems. The biggest differences between tested genotypes were noted for ascorbate peroxidase and glutathione reductase (GR) activity, followed by total ascorbate, phenolics, and glutathione concentration; the least difference was observed in the case of catalase. A large cultivar variation was noted in the anthocyanins and flavonols contents. Distinguishing the cultivars with the lowest, highest, relatively stable or those in which antioxidant content greatly differed depending on growing seasons was attempted. The GR activity is proposed as an environmental stress marker of apple fruit. 相似文献
56.
Piotr Sobkowicz Ewa Tendziagolska Agnieszka Łagocka 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2020,70(4):307-317
ABSTRACTIn experiments with weed harrowing crops are negatively affected by competing weeds but also by the destructive effect of used implement. This research was carried out to find growth stages during which mixture of oat (Avena sativa L.) and triticale (× Triticosecale Wittm.) was resistant to harrowing and was able to effectively recover from this physical disturbance. Plots were harrowed 1–3 times on the same day at six consecutive stages of mixture growth with spring-tine harrow. After the latest harrowing, all plots were sprayed with herbicide to exclude competitive effect of weeds on the mixture. Compared to non-harrowed plots plant density of mixture was significantly reduced after a single cultivation at 1- and 2-leaf stage (20% and 23% respectively), two cultivations at 3-leaf stage (22%) and three at the beginning of the tillering (21%). No yield penalty was noticed for the density reductions, thus showing high ability of mixture to recover from physical disturbance. We recommend plant emergence as an appropriate growth stage for single harrowing of oat-triticale mixture. Two cultivations on the same day should not be planned earlier than at the beginning of tillering. 相似文献
57.
58.
Tae-Won Kim Irene Sartini Beata Łebkowska-Wieruszewska Andrzej Lisowski Amnart Poapolathep Mario Giorgi 《Journal of veterinary pharmacology and therapeutics》2020,43(1):13-18
Use of drug in lactating animal should be carefully considered due to its possibility of changes in pharmacokinetics as well as drug penetration in milk. The aim of this study was to assess the effect of lactation on pharmacokinetics of meloxicam after IV and IM administrations in goats. A crossover design (2 × 2) was used for each lactating and nonlactating group of goats with a 3-week washout period. Meloxicam (0.5 mg/kg) was administered into the jugular vein and upper gluteal muscle by IV and IM routes, respectively. The plasma and milk drug concentrations were determined by high-performance liquid chromatography with diode array detector, and the pharmacokinetic analysis was carried out by noncompartmental analysis. The pharmacokinetic parameters of meloxicam in lactating and nonlactating goats were not significantly different. The IM bioavailability of meloxicam was relatively lower in lactating (75.3 ± 18.6%) than nonlactating goats (103.8 ± 34.7%); however, the difference was not statistically significant. Moreover, AUC ratio between milk and plasma, which represent drug milk penetration, for both IV and IM administrations was less than 1 (about 0.3). In conclusion, pharmacokinetic parameters of meloxicam are not significantly altered by lactation for either the IV or IM routes of administration and this drug does not require a different dosage regimen for lactating animals. 相似文献
59.
Michalczyk Ł Millard AL Martin OY Lumley AJ Emerson BC Chapman T Gage MJ 《Science (New York, N.Y.)》2011,333(6050):1739-1742
The widespread phenomenon of polyandry (mating by females with multiple males) is an evolutionary puzzle, because females can sustain costs from promiscuity, whereas full fertility can be provided by a single male. Using the red flour beetle, Tribolium castaneum, we identify major fitness benefits of polyandry to females under inbreeding, when the risks of fertilization by incompatible male haplotypes are especially high. Fifteen generations after inbred populations had passed through genetic bottlenecks, we recorded increased levels of female promiscuity compared with noninbred controls, most likely due to selection from prospective fitness gains through polyandry. These data illustrate how this common mating pattern can evolve if population genetic bottlenecks increase the risks of fitness depression due to fertilization by sperm carrying genetically incompatible haplotypes. 相似文献
60.
Teresa Ostaszewska MichaŁ Korwin-Kossakowski Jacek Wolnicki 《Aquaculture International》2006,14(1-2):113-126
The aim of the study was to evaluate the effect of short-term starvation on the morphology of the digestive system of juvenile
tench Tinca tinca (L.). The morphological changes in digestive structures of juveniles, fed 70 days starter or Chironomidae larvae, were examined after 1, 12, 24 and 48 h of starvation at 28 °C. The morphological changes in the organisation of the
digestive structures were as follows: (1) Intestine – proteolysis of the intestinal mucosa, especially of enterocytes in apical
part of mucosal folds; (2) Liver – progressive reduction of lipid vacuoles and glycogen granules, and, in effect, volume reduction
of hepatocytes cytoplasm; (3) Pancreas – progressive degeneration of exocrine pancreatic cells, parallel with decrease of
zymogen activity. The fish fed natural food prior to starvation seem to be more resistant to starvation than those fed starter. 相似文献