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21.
Use of Jeffries acid-oxalate treatment in particle-size analyses of Ando soils for breaking up the sand- and silt-size aggregates bound by allophane, allophane-like constituents and hydrous iron oxides was studied. The analyses by this method and those by a method using sonic-wave oscillation were compared for nine Ando soil samples having different clay-mineral compositions and organic-matter contents. There were minor differences in the sand contents between the two analyses, but the clay contents were higher and the silt contents were lower after Jeffries acid oxalate treatment.
Characterization of the silt-size separates by an X-ray powder method, water vapor adsorption and electron microscopy indicated that the lower silt contents after Jeffries acid oxalate treatment were mainly due to dissolution of allophane and allophane-like constituents, whereas the silt-size separates after sonic-wave treatment still contained these mineral constituents. The proposed procedure for particle-size analysis was also useful for two ferruginous soils representing the Hydrandept and Torrox. 相似文献
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Summary Four species of amphistomes were recorded from buffaloes in Peshawar region. The incidence of different species was determined.
The significance of amphistomes in causing disease is discussed.
Sumario Se registraron cuatro especies de Paramfistomas de bufalos en la región de Peshawar. Se determinó la incidencia de las diferentes especies. Se discute el significado de los amfistomas como causantes de Enfermedates.
Résumé 4 espèces d'amphistomes sont signalées chez les buffles de la région de Peshawar. L'incidence de ces différentes espèces est déterminée. L'importance de ces amphistomes sous l'angle de leur pouvoir pathogène est discutée.相似文献
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Allison Leyton Liset Flores Carolina Shene Yusuf Chisti Giovanni Larama Juan A. Asenjo Roberto E. Armenta 《Marine drugs》2021,19(7)
Eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and carotenoids are needed as human dietary supplements and are essential components in commercial feeds for the production of aquacultured seafood. Microorganisms such as thraustochytrids are potential natural sources of these compounds. This research reports on the lipid and carotenoid production capacity of thraustochytrids that were isolated from coastal waters of Antarctica. Of the 22 isolates, 21 produced lipids containing EPA+DHA, and the amount of these fatty acids exceeded 20% of the total fatty acids in 12 isolates. Ten isolates were shown to produce carotenoids (27.4–63.9 μg/g dry biomass). The isolate RT2316-16, identified as Thraustochytrium sp., was the best producer of biomass (7.2 g/L in five days) rich in carotenoids (63.9 μg/g) and, therefore, became the focus of this investigation. The main carotenoids in RT2316-16 were β-carotene and canthaxanthin. The content of EPA+DHA in the total lipids (34 ± 3% w/w in dry biomass) depended on the stage of growth of RT2316-16. Lipid and carotenoid content of the biomass and its concentration could be enhanced by modifying the composition of the culture medium. The estimated genome size of RT2316-16 was 44 Mb. Of the 5656 genes predicted from the genome, 4559 were annotated. These included genes of most of the enzymes in the elongation and desaturation pathway of synthesis of ω-3 polyunsaturated fatty acids. Carotenoid precursors in RT2316-16 were synthesized through the mevalonate pathway. A β-carotene synthase gene, with a different domain organization compared to the gene in other thraustochytrids, explained the carotenoid profile of RT2316-16. 相似文献
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A micropropagation protocol was established for a medicinal plant Vitex negundo. Genetic stability of micropropagated plants was investigated. Multiple shoots were induced from nodal explants cultured on Murashige and Skoog (MS) medium with 0.53 μM naphthalene acetic acid (NAA) and 11.0 μM benzyl aminopurine (BAP) along with additives (ascorbic acid, 283.9 μM; citric acid, 130.1 μM; and arginine, 143.6 μM). Shoots were further multiplied by repeated transfer of the mother explant. The shoots were further multiplied on MS medium + 0.57 μM indole-3-acetic acid (IAA) and 6.6 μM BAP. The micropropagated shoots were pulse treated with 122.5 μM indole-3-butyric acid (IBA), in liquid MS medium and then transferred to autoclaved soilrite. These rooted ex vitro. Shoots were also rooted in vitro on a half-strength MS medium + 2.45 μM IBA. The survival rate of in vitro rooted plantlets was poor during hardening compared to ex vitro rooted plantlets. About 95% of the ex vitro rooted, hardened plantlets survived in the field. Genetic stability of micropropagated plants was tested by using 25 random amplified polymorphic DNA primers. The cloned plants exhibited no variation in banding pattern in comparison with the mother plant. 相似文献
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Ahmad Ibrahim Kudi Caleb Ayuba Babashani Mohammed Chafe Umar Mohammed Yakubu Yusuf Shittu Aminu 《Tropical animal health and production》2019,51(1):73-78
Tropical Animal Health and Production - In comparison with other livestock, tuberculosis (TB) in camels has not been extensively studied in Nigeria. Camels in the hands of Nigerian pastoralists... 相似文献
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Yusuf Ucar Abdullah Kadayıfcı Mehmet Atilla Aşkın Abdullah Kankaya Ulaş Şenyiğit Fatma Yıldırım 《Erwerbs-Obstbau》2016,58(3):169-175
This study was conducted in 2007 and 2008 in order to determine the effects of irrigation frequency on the yield and quality parameters of dwarf trees of the apple cultivar ‘Gala, Galaxy’ in the first and second year of cultivation. Irrigation water was applied at 3?, 5?, 7?, and 10-day intervals as much as the amount of water consumed from the field capacity. Statistical analysis revealed that the effects of irrigation frequency on yield were significant. Since the trees used in the experiment showed mainly vegetative growth, the effects of irrigation frequency on the fruit quality characteristics varied. Irrigation water amount was applied as 355.7–446.5 mm and 359.2–538.9 mm to the experimental treatments in 2007 and 2008, respectively. The evapotranspiration measured was in the range 400.7–491.5 mm in 2007 but in the range 440.2–600.5 mm in 2008, while the yields in the same years ranged from 1.54 to 2.84 t ha?1 and from 2.61 to 6.06 t ha?1. Water use efficiency varied between 2.40 and 4.80 t ha?1mm?1 in the first year of the experiment but between 3.45 and 7.08 t ha?1mm?1 in the second year. The I2 treatment, in which the highest yield and water use efficiency were recorded in both years of the experiment under the experimental conditions, was determined as the irrigation scheduling. 相似文献