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461.
J M Reynes J L Soares C Keo S Ong N Y Heng B Vanhoye 《The Onderstepoort journal of veterinary research》1999,66(2):129-133
In order to provide relevant therapeutic answers to human patients exposed to risk of rabies infection who visit the Institut Pasteur du Cambodge for post-exposure treatment and to improve control of rabies in Cambodia, a pilot study was carried out in Phnom Penh Province in November and December 1997 with three objectives: characterization of the population of animals responsible for the exposure to rabies, observation of the animals concerned, and confirmation of the presence of rabies virus in the province. Between 18 November 1997 and 19 December 1997, 409 of the 741 patients treated at the Institut Pasteur du Cambodge because of an exposure to a known rabies vector were included in the study. The animals concerned were: 401 dogs (98%), six monkeys (1.5%) and two cats (0.5%). Three-hundred-and-seventy of the animals (90.5%) were owned, 4 (1%) were unowned but were available for characterization and observation, and 35 (8.6%) had an unknown ownership status and were not available for further study. The exposures occurred on private property in 84% of the cases, and 80 of the 370 owned animals (22%) lived in the same home as had the patient. The 374 animals with known ownership status were examined. Five were already dead and two of these five dogs had presented clinical signs typical of those of rabies. The male:female sex ratio of the dogs was 2.1:1. The 369 live animals were placed under observation for 10 d immediately after exposure of the humans had taken place. At the end of the period none of the animals had developed clinical signs of rabies, three had died of diseases other than rabies, and one was lost. Tests for the rabies nucleocapsid antigen were positive in two cases (the two suspected rabid dogs), confirming the presence of rabies in Phnom Penh Province. Consequently, we recommend measures to improve the control of rabies in Cambodia. 相似文献
462.
L M Soares D B Rodriguez-Amaya 《Journal of the Association of Official Analytical Chemists》1989,72(1):22-26
A previously published method for ochratoxin A was evaluated and proved appropriate for simultaneous determination of aflatoxins, ochratoxin A, sterigmatocystin, and zearalenone, with considerable savings in time and reagent costs. The detection limits were 2, 5, 15, and 55 micrograms/kg, respectively. The recoveries and coefficients of variation obtained with artificially contaminated samples were 91-101% and 0-16% for aflatoxin B1, 98-117% and 0-17% for sterigmatocystin, and 96-107% and 0-17% for zearalenone, respectively. The coefficients of variation for naturally contaminated samples (aflatoxins in rice and ochratoxin A in beans) ranged from 0 to 8%. The method was used to survey 296 samples that included 10 cultivars of dried beans, 8 types of corn products, 3 types of cassava flour, and both polished and parboiled rice between May 1985 and June 1986 in Campinas, Brazil. Only aflatoxin B1 (9 samples, 20-52 micrograms/kg), aflatoxin G1 (4 samples, 18-31 micrograms/kg), and ochratoxin A (5 samples, 32-160 micrograms/kg) were found. The average contamination percentage was 4.7%; beans showed the highest (6.6%) and rice showed the lowest (3.3%) incidence rates. Zearalenone and sterigmatocystin were not detected. Positive samples were confirmed by chemical derivatization, corroborated by development in 3 solvent systems. 相似文献
463.
Weeds have a great economic impact on agricultural production because they compete with crops for resources and are alternative hosts for pests, microbial pathogens and plant-parasitic nematodes. This study aimed to investigate the susceptibility of weeds to the root-knot nematodes Meloidogyne javanica and Meloidogyne incognita and assess the effect of aqueous weed extracts on M. javanica egg hatching. Four experiments were conducted, two for each nematode species. Weeds were inoculated with 2000 nematode eggs and grown for 60 days under greenhouse conditions. Soyabean cv. Monsoy 7110 was used as control. The weeds Ipomoea grandifolia, Solanum americanum, Digitaria horizontalis, Amaranthus deflexus, Sorghum halepense and Commelina benghalensis were susceptible to M. javanica and M. incognita in at least one experiment (reproduction factor, RF >1). Crotalaria juncea and Eleusine indica were susceptible to M. incognita in one experiment, and Digitaria insularis, Sida rhombifolia, Bidens pilosa, Urochloa decumbens, Crotalaria breviflora, Cenchrus echinatus, Crotalaria ochroleuca and Crotalaria spectabilis were immune or resistant (RF <1 or RF = 0). Alternanthera tenella, C. juncea, S. rhombifolia, C. ochroleuca, C. spectabilis, C. breviflora, B. pilosa, E. indica, U. decumbens and C. echinatus were resistant or immune to M. javanica (RF <1 or RF = 0). Compared with the control (water), all weed extracts reduced M. javanica egg hatch. Our results highlight the importance of weed control in agricultural systems, as nematodes can survive and multiply in weed roots during the off-season. Weed leaves and shoots, however, may be an interesting source of compounds with nematicidal activity. 相似文献
464.
Screening and quantitation of ochratoxin A in corn, peanuts, beans, rice, and cassava 总被引:1,自引:0,他引:1
L M Soares D B Rodriguez-Amaya 《Journal of the Association of Official Analytical Chemists》1985,68(6):1128-1130
To answer the need for simple, economical, rapid methods for mycotoxins, a procedure for screening and quantitation of ochratoxin A was developed. A methanol-aqueous KCl extraction is used, followed by cleanup with clarifying agents and partition into chloroform. Part of the chloroform extract is used for screening and the other part for quantitation by thin layer chromatography (TLC). The screening procedure takes 40 min, using a silica gel/aluminum oxide minicolumn developed for this purpose. The limits of detection are 80 and 10 micrograms/kg, respectively, for minicolumn screening and TLC quantitation. Ammonium sulfate is efficient in cleaning samples of corn and cassava; cupric sulfate is better with peanuts, beans, and rice. Tests were conducted on triplicate spiked samples of yellow corn meal, raw peanuts, dried black beans, polished rice, and cassava flour at different levels (400, 200, 80, 40, and 10 micrograms/kg). Recoveries ranged from 86 to 160% and the coefficients of variation ranged from 0 to 26%. 相似文献
465.
Amanda Oliveira Magalhães Eliane Teixeira Mársico Manoel Soares Soares Júnior Márcio Caliari 《Journal Of Aquatic Food Product Technology》2020,29(7):661-670
ABSTRACT This work evaluated the technological, bacteriological, and sensorial quality of cookies produced with increasing levels (0%, 10%, 20%, 30%, and 40%) of mechanically separated meat flour from tilapia (MSMF) to replace rice flour (RF) in order to identify the optimal level without compromising the overall quality of the product. The cookies were analyzed for expansion index (EI), specific volume (SV), hardness, color, water activity (aw ), coagulase-positive staphylococci, coliforms at 45°C, Salmonella spp., and sensory acceptance. The inclusion of MSMF affected (P < .05) some characteristics such as EI, SV, aw , hardness, and color (L*, a*, b*), but all formulations met the legal bacteriological standards. Cookies with 20% substitution of RF by MSMF presented 58.82% carbohydrates, 18.53% proteins, and 11.31% lipids, and was the most accepted (P < .05); 51% of consumers rated it with a score of six or higher (above I liked slightly). It is concluded that the substitution of 20% of RF by MSMF can be used for nutritional enrichment of widely consumed conventional products. 相似文献
466.
Lucas Silva Padovani Alcione Maria Soares Dutra Oliveira Bernardo Carvalho Dutra Fernando Oliveira Costa Peterson Antônio Dutra Oliveira 《Anatomia, histologia, embryologia》2020,49(6):798-804
The knowledge of anatomical variations of the posterior superior alveolar artery (PSAA) is very important in surgeries for maxillary sinus (MS) elevation and subsequent insertion of dental implants, avoiding common and serious surgical complications. The main objective of this study was to analyse important anatomical variations of the PSAA by means of cone beam computed tomography (CBCT) examinations. 180 tomographic CBCT were analysed, and MS was divided into three equal regions: (I) anterior, (II) intermediate and (III) posterior. Variables evaluated were the visualisation of the artery, distance from the artery to the ridge crest, distance from the artery to the sinus floor, alveolar ridge height and arterial diameter. The PSAA visualisation was more prevalent in males and region III (76.7%). The distance from the artery to the sinus floor presented no significant difference between regions II and III, with both regions showing significantly lower values than region I. A significant difference was observed in the diameter of the arteries with higher prevalence of diameters >1.0 mm in males and <1.0 mm in females. The PSAA can be well visualised frequently with a CBCT, and differences in artery diameter were observed in relation to gender (males > females). Additional care is recommended when it is necessary to extend surgeries to the posterior MS region, avoiding haemorrhages that are associated with failures in these procedures. 相似文献
467.
Claubert W. G. de Menezes Suzan K. V. Bertolucci José E. B. P. Pinto Geraldo A. Carvalho Marcus A. Soares 《Phytoparasitica》2013,41(5):611-613
Vernonia condensata Baker, 1875 (Asteraceae) is a medicinal plant from Brazil considered as a host plant of leafhopper pests in agricultural crops. Aethalion reticulatum Linnaeus, 1767 (Hemiptera: Aethalionidae) was observed in V. condensata in Lavras county, Minas Gerais State, Brazil. Immature and adult individuals of A. reticulatum were collected from V. condensata for identification, which represents the first recording of this pest in this plant. The presence of eggs, nymphs and adults of this insect on the plant shows that A. reticulatum has completed its life cycle, indicating that V. condensata is a potential host plant for A. reticulatum. 相似文献
468.
Mónica J. B. Amorim Susana I. L. Gomes Amadeu M. V. M. Soares Janeck J. Scott-Fordsmand 《Water, air, and soil pollution》2012,223(1):477-482
Energy intake and allocation are mainly used to maintain body functions, such as locomotion, growth, and reproductive output.
It has been observed that environmental pollutants can affect the energy allocation either due to a cost of handling toxicants
or because the toxicant interacts with the storage processes within the organisms. Less than a handful of studies are available
reporting the effect of toxicants on energy reserves in enchytraeids and no studies have dealt with the influence of nanomaterials.
The present paper shows results on the basal energy reserves (lipids, carbohydrates, and proteins) in Enchytraeus albidus and the influence of copper (Cu) salt and Cu nanoparticles on these reserves for two exposure durations. The energy allocation
levels follow what has been reported for other worm species, although lower carbohydrate levels were observed. There were
clear differences between worms exposed to control soils and those exposed to Cu for 3 weeks, but no difference after 6 weeks
exposure. There was no apparent difference between the impacts of the two Cu exposure forms. 相似文献
469.
CA Guymon EN Hoggan NA Clark TP Rieker DM Walba CN Bowman 《Science (New York, N.Y.)》1997,275(5296):57-59
Photopolymerizable diacrylate monomers dissolved in fluid-layer smectic A and smectic C liquid crystal (LC) hosts exhibited significant spatial segregation and orientation that depend strongly on monomer structure. Small, flexible monomers such as 1,6-hexanediol diacrylate (HDDA) oriented parallel to the smectic layers and intercalated, whereas rod-shaped mesogen-like monomers such as 1,4-di-(4-(6-acryloyloxyhexyloxy)benzoyloxy)-2-methylbenzene (C6M) oriented normal to the smectic layers and collected within them. Such spatial segregation caused by the smectic layering dramatically enhanced photopolymerization rates; for HDDA, termination rates were reduced, whereas for C6M, both the termination and propagation rates were increased. These polymerization precursor structures suggest novel materials-design paradigms for gel LCs and nanophase-separated polymer systems. 相似文献
470.
Soares HS Minervino AH Barrêto-Júnior RA Neves KA Oliveira MF Santos JR van Sauers AR Dubey JP Gennari SM 《Journal of zoo and wildlife medicine》2011,42(4):763-765
In this study, the occurrence of antibodies to Toxoplasma gondii in Brazilian agouti (Dasyprocta aguti) was compared by modified agglutination test (MAT) and indirect fluorescent antibody test (IFAT) using anti-capybara conjugate. Sera from 109 animals were tested using MAT (1:25 cut-off) and IFAT (1:16 cut-off); 19% were positive by MAT, and 18% were positive by IFAT. Overall, the 17 IFAT-positive samples were also positive for MAT. The four positive MAT samples with a titer < or = 200 were IFAT negative. All negative samples obtained by MAT matched with the results of the IFAT. Comparing both tests, and considering MAT as the gold standard, the sensitivity of IFAT was 81%, the specificity was 100%, the accuracy was 97%, the positive predictive value (PPV) was 100%, and the negative predictive value 96%. The kappa value agreement was 87.3% (75.1-99.6%). The anti-capybara conjugate can be successfully used to perform IFAT in Brazilian agouti with maximum specificity and PPV. 相似文献