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Margarita Tejada Horst Karl Cristina de las Heras Sanja Vidacek Maria Teresa Solas Maria Luisa Garcia 《Journal Of Aquatic Food Product Technology》2013,22(3):221-236
The distribution of Anisakis larvae in fresh caught hake was studied, and the influence of three infection levels of the viscera (low, medium, high) on quality changes of deep frozen muscle was followed over 220 days. Differences in quality were attributed more to the size of the individuals than to the infection degree of the three groups. The removal of belly flaps diminished the risk of consumers’ infection and sensitization as prevalence and intensity was reduced to 75.6 and 5.9%, respectively. Allergens were detected after 220 days frozen storage, which represents a risk for consumers already allergic to Anisakis. 相似文献
154.
Zhao X Corrales M Zhang C Hu X Ma Y Tauscher B 《Journal of agricultural and food chemistry》2008,56(22):10761-10766
Chinese purple corn extracts ( Zea mays L., Zhuozhou, Hebei, China) (EZPC) were selected among five Chinese purple corn hybrids due to their higher anthocyanin content, and their thermal stability was evaluated. The total anthocyanin content and total phenolic content of EZPC were 304.5 +/- 16.32 mg of cyanidin-3-glucoside equiv/100 g of dry seeds and 489.8 +/- 24.90 mg of gallic acid equiv/100 g of dry seeds, respectively. Moreover, the individual anthocyanins of EZPC were determined by HPLC-DAD/ESI-MS analysis. Seven main compounds were determined, including cyanidin-3-(malonylglucoside), cyanidin-3-O-glucoside-2-malonylglucoside, cyanidin-3-O-glucoside, peonidin-3-O-glucoside, peonidin-3-(malonylglucoside), pelargonidin-3-(6'-malonylglucoside), and peonidin-3-(dimalonylglucoside). The thermal stability of EZPC was studied by differential scanning calorimetry. Thermodynamic analysis showed that the conversion of EZPC followed an Arrhenius relationship, where the delta enthalpy (H) and activation energy (E(a)) were 97.0 J/g and 204 +/- 2.72 kJ/mol, respectively. Furthermore, the relationships between the degree of conversion of EZPC and time or temperature were reported. This study demonstrated that the evaluated Chinese purple corn hybrids are a natural source of anthocyanins and are stable over a wide range of temperatures and times. 相似文献
155.
María Menéndez-Gutiérrez Margarita Alonso Gabriel Toval Raquel Díaz 《Annals of Forest Science》2017,74(4):76
Key message
Pinus pinaster Ait. susceptibility to pinewood nematode significantly differed among provenances, and the two Atlantic provenances of the Iberian Peninsula being the most affected. However, significant provenance × environment interaction was found. Provenance susceptibility was related to basal diameter, number of branches and oleoresin flow, and some climatic parameters.Context
The pinewood nematode Bursaphelenchus xylophilus, native to North America, is an important pest affecting pine forests throughout Eurasia. In Europe, it has been detected in Portugal and Spain and is primarily associated with Pinus pinaster, an important Mediterranean tree species.Aims
We have investigated the differences in susceptibility among several P. pinaster provenances in the Iberian Peninsula and France, as well as their relationship to certain growth traits and physiological parameters.Methods
Three independent inoculation tests were performed on 3 to 4-year-old trees, followed by assessment of growth traits and physiological variables, along with time course destructive sampling for nematode quantification.Results
The results showed significant differences among provenances for almost all growth traits, wilting, and mortality, though a significant provenance × environment interaction was also detected. Two Atlantic provenances, Noroeste-Litoral and Leiria, displayed the largest susceptibility to pinewood nematode. Changes in susceptibility to B. xylophilus between experiments were influenced by temperature and seasonality. Autumn precipitation and mean maximum temperature during summer at the original provenance sites could be related to provenance susceptibility.Conclusion
Noroeste-Litoral and Leiria were the most disease-affected provenances. This study emphasizes the need for further research on how tree growth stage influences susceptibility and on the possibility of cross-breeding among provenances.156.
157.
Naber N Minehardt TJ Rice S Chen X Grammer J Matuska M Vale RD Kollman PA Car R Yount RG Cooke R Pate E 《Science (New York, N.Y.)》2003,300(5620):798-801
We have used adenosine diphosphate analogs containing electron paramagnetic resonance (EPR) spin moieties and EPR spectroscopy to show that the nucleotide-binding site of kinesin-family motors closes when the motor.diphosphate complex binds to microtubules. Structural analyses demonstrate that a domain movement in the switch 1 region at the nucleotide site, homologous to domain movements in the switch 1 region in the G proteins [heterotrimeric guanine nucleotide-binding proteins], explains the EPR data. The switch movement primes the motor both for the free energy-yielding nucleotide hydrolysis reaction and for subsequent conformational changes that are crucial for the generation of force and directed motion along the microtubule. 相似文献
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159.
Bacillus thuringiensis Berliner var. israelensis de Barjac (Serotype H-14) (B.t.i.) at a concentration of 1.6 ppm/10 min and a toxicity of 1500 AAU/mg was tested against Simulium chutteri Lewis larvae in the Orange River near Prieska, South Africa. Samples of benthic fauna from the stones-in-current biotope were collected before application of the product and at various intervals up to 80 h afterwards at 4 stations from 200 m to 11 km downstream of the application site. Fauna drift increased slightly after the arrival of the Bacillus at 2 stations 1.4 and 6 km respectively downstream of the application site. Large numerical decreases in benthic simuliid larval numbers after the application of B.t.i. in the Orange River were not statistically different (P greater than 0.05). This indicated that the size of replicated samples that showed significant decreases (P less than 0.05) of simuliid numbers in the Vaal River was not adequate to show statistical differences in the Orange River. The quantity of dead larvae on stones collected from rapids after application of the B.t.i., and the numerical decreases found by comparing median values of larval counts on stones indicated that B.t.i. effectively killed simuliid larvae. Three days after application of the Bacillus, recruitment of small simuliid larvae on stones 1.4 km downstream of the application site was discernible again. Tanytarsini were also numerically reduced after B.t.i. application. At a flow rate of 38 m3/s B.t.i. was visibly effective in killing S. chutteri up to 6 km downstream of the application site and statistically significant decreases (P less than 0.05) in numbers of larvae were seen at a site 11 km downstream of the application site.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
160.