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991.
The ethanolic extract from the stem of Brosimum potabile afforded (-)-centrolobin (1), isolated for the first time in this genus. The identification of this compound included COSY and NOESY two-dimensional NMR data. 相似文献
992.
993.
Association between the presence of serum antibodies against Neospora spp. and fetal loss in equines
Villalobos EM Ueno TE de Souza SL Cunha EM do Carmo Custódio de Souza Hunold Lara M Gennari SM Soares RM 《Veterinary parasitology》2006,142(3-4):372-375
A study of the association between the presence of serum antibodies against Neospora spp. and fetal loss was performed using serum samples of horses submitted to the laboratory for the detection of antibodies to Equine Herpesvirus-1 and Equine Infectious Anemia Virus. The sera submitted for equine infectious anemia testing were from horses declared healthy and those submitted for the detection of antibodies to Equine Herpesvirus-1 were from mares with late clinical signs of reproductive disorders or males living in close contact with diseased mares. For the detection of Neospora spp. infection, the immunofluorescent antibody test was employed, using a cut-off titer of 50 as significant for the presence of antibodies. Among the 483 mares in the diseased group, 15.1% (73/483) was reactant, while 5.8% (19/325) was seropositive in the healthy group. The results show that late clinical signs of reproductive disorders in mares are positively associated (p<0.001) to infection with protozoa belonging to the genus Neospora and point to the fact that the participation of this group of coccidia in the genesis of reproductive disorders in equine must be investigated. 相似文献
994.
995.
Talles Iwasawa Neves Claudio Augusto Uyeda Cleiton de Souza Silva Raphael Abrahão 《Water, air, and soil pollution》2018,229(4):132
Biosolid, i.e., dehydrated sludge from effluent treatment stations, has been progressively used as an agricultural fertilizer due to its high organic matter and nutrient contents. Elephant grass (Cenchrus purpureus (Schumach.) Morrone) presents easy adaptation and high yields, being used for animal feeding and for energy purposes. The objective of this work was to analyze the production and bromatological parameters of elephant grass with four different doses of biosolid, one of chemical fertilizer and a control plot, with two replicates each. A field experiment was carried out using a randomized block design with three blocks, totaling 18 plots, which received biosolid fertilization at 1×, 2×, 4×, and 8× the levels recommended by the Brazilian National Environment Council, along with conventional chemical fertilization and no fertilization, all under similar drip irrigation. Tukey’s test indicated a significant difference at p?<?0.01 for total production in the first cut and acid detergent fiber in the second cut. At p?<?0.05, significant differences were detected for total nitrogen and total protein in the first cut. The elephant grass yield under “1× biosolid” was similar to that reached with chemical fertilization. Physical and bromatological characteristics indicated potential use as animal feed and energy source. For doses higher than specified by Brazilian standards (2×, 4×, and 8×), further studies are required to verify possible contamination from heavy metals, pathogenic microorganisms, and n. 相似文献
996.
Adriana Reatto Ary Bruand Eder de Souza Martins Fabrice Muller Euzebio Medrado da Silva Osmar Abílio de Carvalho Jr. Michel Brossard Guy Richard 《CATENA》2009
Brazilian Latosols are characterized by low activity clay, little horizon differentiation, a weak macrostructure and a strong microgranular structure. The development of the latter that was reported as being possibly related to the fine material mineralogy, location in the landscape, parental material and biological activity is still under discussion. The aim of this study is to discuss the origin of the microgranular structure of Latosols located in the Brazilian Central Plateau. Ten Latosols (L) developed in different parent materials were selected along an approximately 350-km long regional toposequence across the South American Surface (SAS) (L1 to L4) and Velhas Surface (VS) (L5 to L10). The structure of the Latosols was studied in the field and samples of the diagnostic Bw horizons were collected for laboratory analyses. Basic soil characterization was performed on the < 2-mm material according to the Brazilian standard procedures. The SiO2, AL2O3, Fe2O3 and TiO2 content was determined after dissolution with 1:1 H2SO4. The microstructure was studied in optical microscopy and scanning electron microscopy in thin sections. The results showed a varying compound strong microgranular structure and weak to moderate medium sub-angular blocky structure independently of the landscape position as well as the parental material, except for the Latosol developed on a quartzite. The Latosols were classified as gibbsitic-sesquioxidic, kaolinitic non-sesquioxid, or kaolinitic-sesquioxid Latosols but there was no relationship between their composition and the development of the microgranular structure in the Bw horizon. The analyses showed indeed several types of microgranular structure with different proportions but without any relationship with their texture and mineralogy. Actually, the types of microgranular structure appeared to be mainly related to soil bioturbation by termites and eventually secondarily by ants. Thus, the weak macrostructure and strong microgranular structure of the Latosols studied, the little vertical differentiation of the horizons, and the lack of a clear relationship between their landscape position and parent material characteristics would result from long-term biotic action with high probability. 相似文献
997.
Tatiana da Silva Souza Dejanira de Franceschi de Angelis Carmem Silvia Fontanetti 《Water, air, and soil pollution》2011,221(1-4):235-244
Diplopods are components of the edaphic fauna, which makes them suitable bioindicators of soil quality. Some characteristics of the fat body of diplopods make it suitable for ecotoxicological studies. This organ, composed of diffuse tissue, fills the body cavity; it presents intense metabolic activity associated with lipid, glycogen, protein, and uric acid storage, being also responsible for storage, neutralization, and excretion of substances that are not useful to the organism. The present study aimed to investigate whether the perivisceral fat body of Rhinocricus padbergi can be used as a target organ in ecotoxicological studies and to identify possible histological and histochemical biomarkers in this organ. Upon examining the perivisceral fat body of individuals of R. padbergi exposed to different concentrations of industrial soil contaminated with polycyclic aromatic hydrocarbons (?? 2,749.0 mg/kg) and metals (?? 40,355.8 mg/kg), we have found evidence that this organ is sensitive to environmental pollutants present in the soil. The loss of integrity of the cell boundary associated with cytoplasmatic disorganization and depletion in total proteins, neutral polysaccharides, calcium, and lipids can be considered stress biomarkers for R. padbergi. 相似文献
998.
Ramos Vda S Silva Gde S Freire Md Machado OL Parra JR Macedo ML 《Journal of agricultural and food chemistry》2008,56(23):11348-11355
A novel trypsin inhibitor (PFTI) was isolated from Plathymenia foliolosa (Benth.) seeds by gel filtration chromatography on a Sephadex G-100, DEAE-Sepharose, and trypsin-Sepharose columns. By SDSPAGE, PFTI yielded a single band with a M(r) of 19 kDa. PFTI inhibited bovine trypsin and bovine chymotrypsin with equilibrium dissociation constants (K(i)) of 4 x 10(-8) and 1.4 x 10(-6) M, respectively. PFTI retained more than 50% of activity at up to 50 degrees C for 30 min, but there were 80 and 100% losses of activity at 60 and 70 degrees C, respectively. DTT affected the activity or stability of PFTI. The N-terminal amino acid sequence of PFTI showed a high degree of homology with various members of the Kunitz family of inhibitors. Anagasta kuehniella is found worldwide; this insect attacks stored grains and products of rice, oat, rye, corn, and wheat. The velvet bean caterpillar (Anticarsia gemmatalis) is considered the main defoliator pest of soybean in Brazil. Diatraea saccharalis, the sugar cane borer, is the major pest of sugar cane crops, and its caterpillar-feeding behavior, inside the stems, hampers control. PFTI showed significant inhibitory activity against trypsin-like proteases present in the larval midguts on A. kuehniella and D. saccharalis and could suppress the growth of larvae. 相似文献
999.
Dutra PM Rodrigues CO Romeiro A Grillo LA Dias FA Attias M De Souza W Lopes AH Meyer-Fernandes JR 《Phytopathology》2000,90(9):1032-1038
ABSTRACT In the present work ectophosphatase activities of three trypanosomatid parasites of plants were characterized using intact cells. Phytomonas fran?ai, Phytomonas mcgheei, and Herpetomonas sp. hydrolyzed p-nitro-phenylphosphate at a rate of 5.40, 7.28, and 25.58 nmol Pi/mg of protein per min, respectively. Experiments using classical inhibitors of acid phosphatases such as sodium orthovanadate (NaVO(3)) and sodium fluoride (NaF) showed a decrease in phosphatase activities. Lithium fluoride (LiF) and aluminum chloride (AlCl(3)) were also used. Although AlCl3 had no effect, LiF was able to promote a decrease in the phosphatase activities. Interestingly, the inhibition caused by LiF was enhanced by the addition of AlCl3 during the reaction, probably due to the formation of fluoroaluminate complexes. This effect was confirmed by cytochemical analysis. In this assay, electron-dense cerium phosphate deposits were visualized on the external surface of the three parasites. 相似文献
1000.