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101.
Recombinant cDNA probe from bluetongue virus genome segment 10 for identification of bluetongue virus 总被引:2,自引:0,他引:2
C A de Mattos C C de Mattos B I Osburn 《Journal of veterinary diagnostic investigation》1989,1(3):237-241
Genome segment 10 of bluetongue virus (BTV) serotype 11 UC8 strain was cloned and subsequently hybridized to viral double-stranded RNA extracted from 90 field isolates of BTV serotypes 10, 11, 13, and 17; the prototype strains of BTV 2, 10, 11, 13, and 17; the prototype strain epizootic hemorrhagic disease virus (EHDV) serotype 1; and 4 field isolates of EHDV serotype 2. The 90 field isolates were obtained from different counties in California, Louisiana, and Idaho during the years 1979, 1980, and 1981. The cloned genetic probe hybridized with all the BTV samples tested, showing different degrees of cross-hybridization at the stringency conditions used in this study. This indicated that BTV genome segment 10 has conserved nucleotide sequences among the BTV serotypes 2, 10, 11, 13, and 17. No cross-hybridization signals were detected between the cloned genome segment 10 of BTV 11 UC8 strain and the prototype strain of EHDV serotype 1 and the field isolates of serotype 2. This probe recognized a wide variety of BTV isolates. 相似文献
102.
Geisa Lima Mesquita Francisco Andr�� Ossamu Tanaka Heitor Cantarella Dirceu Mattos Jr 《Water, air, and soil pollution》2011,219(1-4):143-156
Fluoride (F) is an air pollutant that causes phytotoxicity. Besides the importance of this, losses of agricultural crops in the vicinity of F polluting industries in Brazil have been recently reported. Injuries caused to plant leaf cell structures by excess F are not well characterized. However, this may contribute to understanding the ways in which plant physiological and biochemical processes are altered. A study evaluated the effects of the atmospheric F on leaf characteristics and growth of young trees of sweet orange and coffee exposed to low (0.04 mol L?1) or high (0.16 mol L?1) doses of HF nebulized in closed chamber for 28 days plus a control treatment not exposed. Gladiolus and ryegrass were used as bioindicators in the experiment to monitor F exposure levels. Fluoride concentration and dry mass of leaves were evaluated. Leaf anatomy was observed under light and electron microscopy. High F concentrations (~180 mg kg?1) were found in leaves of plants exposed at the highest dose of HF. Visual symptoms of F toxicity in leaves of citrus and coffee were observed. Analyses of plant tissue provided evidence that F caused degeneration of cell wall and cytoplasm and disorganization of bundle sheath, which were more evident in Gladiolus and coffee. Minor changes were observed for sweet orange and ryegrass. Increase on individual stomatal area was also marked for the Gladiolus and coffee, and which were characterized by occurrence of opened ostioles. The increased F absorption by leaves and changes at the structural and ultrastructural level of leaf tissues correlated with reduced plant growth. 相似文献
103.
Helio Garcia Leite Mayra Luiza Marques da Silva Daniel Henrique Breda Binoti Leonardo Fardin Fausto Hissashi Takizawa 《European Journal of Forest Research》2011,130(2):263-269
The objective of this study was to obtain neural networks that would precisely estimate inside-bark diameter (d ib ) and heartwood diameter (d h ) and compare to the results obtained by the Taper models. The databank was formed so as to eliminate inconsistent and biased data, and stratified: minimum d ib of 4, 6 and 8 cm and minimum d h of 10, 15 and 20 cm. The adjusted Taper model used was the Kozak model. For the fitting of artificial neural networks (ANN), tests were performed to identify the independent variables and the database scope level, i.e., the following input variables were tested: diameter at breast height (dbh), total height (H), height at diameter d ib or d h (h) and outside-bark diameter at h (d ob ), bark thickness at 1.3 m and project, and the scope at database level or project level. The estimates obtained by the neural networks and Kozak model were evaluated by residual graphs in function of the respective diameter observed and graph of the observed versus estimated values. ANN were found to be more efficient in estimating inside-bark and heartwood diameters for Tectona grandis trees than the Kozak model. The variables that must be used to fit the networks are dbh, H, h and d ob . Stratification by project results in precision gain, with precision being higher for wider commercial diameters. Thus, linear-type artificial neural networks can be efficient in describing the taper of Tectona grandis trees. 相似文献
104.
C C de Mattos C A de Mattos B I Osburn M Ianconescu R Kaufman 《American journal of veterinary research》1991,52(11):1794-1798
A recombinant cDNA probe from genome segment 5 obtained from a virulent US bluetongue virus strain (BTV-11 strain UC8) was hybridized to US and Israeli BTV prototypes and field isolates. The cloned genetic probe hybridized with US BTV prototype 10, but not with US prototypes 2, 11, 13, and 17; with the avirulent BTV-11 strain UC2; and with the Israeli prototype 10. When the probe was hybridized to field isolates from the US serotypes, it hybridized to 12 of 14 BTV-10 isolates and 4 of 17 BTV-11 samples, but not to the BTV-13 and BTV-17 samples tested. Hybridization was not observed with the Israeli field isolates studied. Results indicate that a reassortant event occurred between a strain of US BTV-10 and US BTV-11 that originated the BTV-11 strain UC8. 相似文献
105.
Ivanete Kotait Rafael de Novaes Oliveira Maria Luiza Carrieri Juliana G. Castilho Carla Isabel Macedo Patrícia Mariano Cruz Pereira Vanner Boere Lúcia Montebello Charles E. Rupprecht 《Zoonoses and public health》2019,66(1):47-59
Rabies virus (RABV) does not persist in the environment as it is a very fragile agent. The primary hosts are mammalian species in the orders Carnivora and Chiroptera. Since the late 1980s, RABV has been isolated from non‐human primates, Callithrix jacchus (the white‐tufted marmoset), in four coastal states (Rio Grande do Norte, Ceará, Piauí and Pernambuco) in north‐eastern Brazil, where this species is indigenous. The original habitat of C. jacchus consisted of two Brazilian biomes, the Atlantic Forest and the Caatinga. However, these marmosets have since adapted to other ecosystems as a result of human activities. Between 1988 and 1989, RABV isolates were obtained from white‐tufted marmosets in the state of Rio Grande do Norte, but antigenic and genetic identification studies were not conducted at that time. In the following years, three additional states reported cases (Ceará, Piauí and Pernambuco). In two of these states (Ceará and Piauí), human cases of rabies transmitted by marmosets were reported. According to Brazilian Health Ministry data, at least 19 human cases in which this species was the source of infection were registered in between 1990 and 2016. Recent findings in laboratory tests of 12 rabid samples from humans and marmosets and the regional transmission among these animals for over 20 years, together with the gradual increase in the affected geographic area, support the concept of the emergence of a new RABV reservoir. Regional tourism, the wild animal trade and the cultural practice of maintaining these animals as pets, particularly in coastal regions, appear to be major risk factors for the increase in human cases. Additional epidemiological and ecological studies are required to better understand local disease dynamics and to identify ideal opportunities for prevention and control of this fatal infection. 相似文献
106.
107.
Detection of Vaccinia virus during an outbreak of exanthemous oral lesions in Brazilian equids 下载免费PDF全文
108.
Gabriela Almeida Bastos Leydiana Duarte Fonseca Adriano Vinícius de Paiva Ferreira Marco Aurélio Morais Soares Costa Maria Luiza França Silva Viviane de Oliveira Vasconcelos Rogério Marcos de Sousa Eduardo Robson Duarte 《Tropical animal health and production》2017,49(5):937-943
In this study the helminthiasis and anthelmintic effectiveness in ewes and lambs were evaluated in a semiarid region of Brazil. Twelve sheep farms were investigated using semi-structured questionnaires and fecal egg count (FEC) reduction test was employed to analyze the profile of anthelmintic resistance. Groups of at least 10 animals with FEC ≥ 300 were selected. After 12 h of fasting, homogeneous groups of lambs or ewes were treated with albendazole, levamisole moxidectin, or oxfendazole and control groups were not treated. Feces were collected before treatments and 14 days after, and larvae genera were identified after cuprocultures in both periods. Extensive grazing was the predominant creation system, using hybrid Santa Ines animals. The separation by age was promoted in 75% of herds; however, maternity pickets there were only in three farms. The strategic treatments were performed only in 8.4% of sheep farms and 16.6% used the anthelmintic efficacy test and alternated anthelmintic classes after 1 year. The initial FEC means for lambs were significantly higher than ewe FEC averages. For lamb tests, moxidectin and levamisole showed higher efficacy (p ≤ 0.05) than benzimidazoles. For ewe tests, moxidectin and levamisole showed efficiencies >75%. Haemonchus spp. and Trichostrongylus spp. were the most frequent nematodes before treatments and the genus Haemonchus was the most prevalent after anthelmintic treatments (p < 0.05). Variations of anthelmintic susceptibility were observed for categories and herds evaluated, which emphasizes the importance of the effectiveness tests for the choice of anthelmintics for ewes and lambs. 相似文献
109.
Boaventura MA Pereira RG de Oliveira Freitas LB Dos Reis LA da Silva Vieira H 《Journal of agricultural and food chemistry》2008,56(9):2985-2988
Novel kaurane ditepene monoamides were synthesized in good yields directly from kaurenoic ( 1) and grandiflorenic ( 2) acids and unprotected symmetrical diamines, using a modified protocol for monoacylation. Amides from 1 and 2 and monoamines were also obtained and tested against seed germination and growth of radicle and shoot of Lactuca sativa (lettuce), at 10 (-3), 10 (-5), and 10 (-7) M. Amides from symmetrical diamines showed significant inhibitory activity at higher concentrations. 相似文献
110.
Geometric approach to evaluate the energy/protein balance in tambaqui (Colossoma macropomum): Can fish ensure nutritional intake targets by postingestion signals? 下载免费PDF全文
E.C.T.N. Filho B.O. Mattos A.A. Santos K.A. Barreto R.C.B. Albinati L.V. Oliveira Vidal F.J. Sánchez‐Vázquez R. Fortes‐Silva 《Aquaculture Nutrition》2018,24(2):741-747
The aim of this study was to investigate the ability of tambaqui (Colossoma macropomum) to balance the energy (E) and protein (P) ratio by encapsulated diets (without sensory properties). Thirty fish (71.37 ± 2.58 g) were distributed in six 250‐litre tanks. Protein (P), carbohydrate (C) and fat (F) were encapsulated separately to ensure the same sensory properties of each macronutrient. Diets varied in terms of macronutrients to allow the maximal/minimal possibility of ingesting each nutrient following a geometric approach. P, C and F capsules were provided for 40 days (phase 1). After this procedure, fish were subjected to fixed low and poor protein challenges (200 g/kg), and freely to C + F, to evaluate whether they maintained a given intake target (phase 2). As a result, tambaqui showed an intake target at 300 g/kg of crude protein and 16.74 MJ per kg. Give the possibility of freely feeding protein, fish regulated their feed intake and showed a constant E/P ratio pattern (5.024‐5.861 MJ/kg). When protein was restricted and fixed at 200 g/kg, fish maintained similar feed consumption until the end of phase 1, probably to keep a minimal protein amount according to their nutritional requirements. 相似文献