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21.
An integrated analytical system consisting of combined scanning electron microscopy and x-ray analysis, atomic absorption, colorimetry and coulometry was used to study rain water chemistry. The coulometry facilitated the determination in molarities of strong and non-volatile and volatile weak acids. The pH of individual rains in St. Paul — Minneapolis, Minnesota ranged from 4.0 to 5.65 during the summer of 1974. Samples of a given rain from different sites had different qualitative and quantitative bases for the measured pH. Increase in strong acid concentrations with a decrease in pH was not an exclusive phenomenon. Molarities of weak acids (volatile and/or non-volatile) also increased with an increase in the acidity. Studies conducted on Twin Cities rain samples indicated that the total salt content expressed from the electrical conductivity could not be accounted for by the total concentrations of individual metals quantified (Fe, Pb, Zn, Mn, Cu, Cr, Cd, Ca, Mg, Na, and K). In addition, no correlation could be shown between the contents of S04 ?, NO3 ?, Cl2 ?, and PO4 ? and the observed changes in pH. 相似文献
22.
Castro-Tirado AJ Zapatero-Osorio MR Caon N Cairos LM Hjorth J Pedersen H Andersen MI Gorosabel J Bartolini C Guarnieri A Piccioni A Frontera F Masetti N Palazzi E Pian E Greiner J Hudec R Sagar R Pandey AK Mohan V Yadav RK Nilakshi Bjornsson G Jakobsson P Burud I et al 《Science (New York, N.Y.)》1999,283(5410):2069-2073
Broad-band (ultraviolet to near-infrared) observations of the intense gamma ray burst GRB 990123 started approximately 8.5 hours after the event and continued until 18 February 1999. When combined with other data, in particular from the Robotic Telescope and Transient Source Experiment (ROTSE) and the Hubble Space Telescope (HST), evidence emerges for a smoothly declining light curve, suggesting some color dependence that could be related to a cooling break passing the ultraviolet-optical band at about 1 day after the high-energy event. The steeper decline rate seen after 1.5 to 2 days may be evidence for a collimated jet pointing toward the observer. 相似文献
23.
Interferon-beta-related DNA is dispersed in the human genome 总被引:6,自引:0,他引:6
A D Sagar P B Sehgal L T May M Inouye D L Slate L Shulman F H Ruddle 《Science (New York, N.Y.)》1984,223(4642):1312-1315
Interferon-beta 1 (IFN-beta 1) complementary DNA was used as a hybridization probe to isolate human genomic DNA clones lambda B3 and lambda B4 from a human genomic DNA library. Blot-hybridization procedures and partial nucleotide sequencing revealed that lambda B3 is related to IFN-beta 1 (and more distantly to IFN-alpha 1). Analyses of DNA obtained from a panel of human-rodent somatic cell hybrids that were probed with DNA derived from lambda B3 showed that lambda B3 is on human chromosome 2. Similar experiments indicated that lambda B4 is not on human chromosomes 2, 5, or 9. The finding that DNA related to the IFN-beta 1 gene (and IFN-alpha 1 gene) is dispersed in the human genome raises new questions about the origins of the interferon genes. 相似文献
24.
Sagar Sharath V. Saini Kuldeep Sharma Anil Kumar Kumar Sachin Kumar Rinesh Fular Ashutosh Shakya Mukesh Upadhaya Deepak Nagar Gaurav C. Shanmuganath Samanta Subhamoy Kumar Suman Ghosh Srikant 《Tropical animal health and production》2020,52(2):611-618
Tropical Animal Health and Production - The isolates of Rhipicephalus microplus collected from Madhya Pradesh (MP), Punjab (PJB) and Uttar Pradesh (UP) states of India were characterized using... 相似文献
25.
Mitra Sirsha Firake D. M. Umesh K. P. Pandey Prashasti P. Pandit Sagar 《Journal of pest science》2021,94(4):1091-1103
Journal of Pest Science - Trap crops are used for pulling the pest load from the main crops toward themselves. Here, we report a switching by a polyphagous pest, Spodoptera litura, from trap crop... 相似文献
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Soils are the third biggest sink of carbon on the earth. Hence, suitable land uses for a climatic condition are expected to sequester optimum atmospheric carbon in soils. But, information on how climatic conditions and land uses influence carbon accumulation in the soils on the Himalayan Mountains is not known. This study reports the impact of four climatic conditions (sub-tropical, altitude: 500–1200 m; temperate 1200–2000 m; lower alpine 2000–3000 m; upper alpine, 3000–3500 m) and four land uses (forest, grassland, horticulture, agriculture) on the concentrations and stocks of soil organic carbon (SOC) in upper (0–30 cm) and deeper (30–100 cm) soil depths on the western Himalayan Mountains of India. The study also explored the drivers which influenced the SOC stock build up on the mountains. Rainfall and soil moisture showed quadratic relations, whereas temperature declined linearly with the altitude. SOC stock as well as concentration was the highest (101.8 Mg ha− 1 in 0–30 cm, 227.97 Mg ha− 1 in 0–100 cm) in temperate and the lowest in sub-tropical climate (37 Mg ha− 1 in 0–30 cm, 107.04 Mg ha− 1 in 0–100 cm). Pattern of SOC stock build up across the altitude was: temperate > lower alpine > upper alpine > sub-tropical. SOC stocks in all land uses across the climatic conditions, except agriculture in lower alpine, was higher (0.7 to 41.6%) in the deeper than upper soil depth. SOC stocks in both the depths showed quadratic relations with soil temperature and soil moisture. Other factors like fine soil particles, land-use factor and altitude influenced positively whereas slope and pH, negatively to the SOC stocks. In all climatic conditions, other than temperate, SOC stocks were greater in natural ecosystems like forests and pastures (112.5 to 247.5 Mg ha− 1) than agriculture (63 to 120.4 Mg ha− 1). In temperate climate, SOC stock in agriculture (253.6 Mg ha− 1) on well formed terraces was a little higher than forest (231.3 Mg ha− 1) on natural slope. These observations, suggest that land uses on temperate climate may be treated as potential sinks for sequestration of the atmospheric carbon. However, agriculture in subtropical climate need to be pursued with due SOC protection measures like the temperate climate for greater sequestration of the atmospheric carbon. 相似文献
29.
Yogesh Chander Simone Oliveira Sagar M. Goyal 《Veterinary journal (London, England : 1997)》2011,187(1):139-141
A PCR based method was developed for the identification of ceftiofur resistance genes (blaCMY-2, blaTEM-1, and ampC) in swine bacterial pathogens. Using this method, the ceftiofur resistant (n = 76) and susceptible (n = 45) strains of Bordetella bronchiseptica, Salmonella spp., Escherichia coli, and Pasteurella multocida were screened for the presence of these three genes. The resistant genes were detected in 70% (blaTEM-1), 68% (blaCMY-2) and 45% (ampC) of the resistant isolates and in 18% (blaTEM-1), 27% (blaCMY-2), and 36% (ampC) of the susceptible isolates. Results obtained in the present study showed widespread distribution of these three resistance genes in ceftiofur-resistant swine pathogens. It was also observed that more pathogens are acquiring these resistance genes. 相似文献
30.
The trophic and spatial inter-relations between 2 small native fish (Galaxias vulgaris Stokell and G. paucispondylus Stokell, Galaxiidae) and juveniles of 2 introduced fish (Oncorhynchus tshawytscha Walbaum and Salmo trutta L., Salmonidae) were investigated in a New Zealand stream. Interspecific overlap in timing of feeding among these four fish species was greatest between pre-dusk and pre-dawn (1730-0530). Aquatic invertebrates were consumed exclusively by all fish species except O. tshawytscha, which also preyed on Trichoptera imagos, particularly at night. Dietary similarities were least between galaxiids, moderate between galaxiids and salmonids, and greatest between salmonid species. Both galaxiid species were found primarily in riffles, with G. vulgaris occupying slightly deeper (≤0.3 m) and slower (0.5–0.8 m. s?1) waters than did G. paucispondylus (≤0.2 m deep and 0.7-1.0 m. s?1 water velocity); salmonids were mostly in pools and runs, with O. tshawytscha occupying slightly slower (0.1-0.2 m. s?1) and deeper (≤0.5 m) waters than those occupied by S. trutta (0.2–0.5 m. s?1 water velocity and ≤0.4 m deep). The interspecific differences in feeding and microdistribution presumably reduce interaction between sympatric populations of galaxiids and salmonids. 相似文献