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111.
Enio Tarso de Souza Costa Luiz Roberto Guimarães Guilherme Guilherme Lopes Nilton Curi 《Water, air, and soil pollution》2012,223(4):1661-1670
Assessing multielement adsorption of trace metals on materials having potential to be used as soil amendments is an essential
stage for the remediation success, as soil contamination rarely occurs with a single element. This study evaluated mono-/multielement
adsorption of Zn, Cu, Cd, and Pb on aluminum (AMB) and iron mining by-products (IMB, used for comparison). Prior to adsorption,
these products were characterized by X-ray diffraction, isoelectric point, infrared spectroscopy, scanning electron microscopy,
and microwave furnace digestion. Sorption experiments comprised: (1) pH adjustment (5.5, 6.5, and natural suspension pH),
(2) mono- and multielement adsorption, and (3) desorption. Rising pH from 5.5 to natural suspension values (9.5) increased
monoelement adsorption of Zn, Cu, Cd, and Pb on AMB up to 3.8-, 1.4-, 6.2-, and 1.1-fold, whereas multielement adsorption
was increased up to 17.3-, 2.0-, 20.3-, and 1.2-fold, respectively. Zinc and Cd were less adsorbed than Cu and Pb and more
affected by competition. Multielement adsorption at 5.5 pH in AMB resulted in smaller adsorption of Zn (up to 4.6-fold), Cu
(1.4-fold), Cd (3.3-fold), and Pb (1.1-fold) when compared with monoelement adsorption. The lower the pH, the smaller the
adsorption and the higher the desorption. The AMB showed higher capacity to maintain the elements adsorbed than the IMB. 相似文献
112.
Paulo Renato Matos Lopes Renato Nallin Montagnolli Ederio Dino Bidoia 《Water, air, and soil pollution》2012,223(7):3673-3688
Electrochemical processes in industrial effluents have been studied as a means to obtain higher efficiency in wastewater treatment. Heterogeneous photocatalysis appears as a low-cost alternative through the use of lower wattage lamps and thermal TiO2 films. Photocatalysis became a clean process for water treatment due to hydroxyl radicals generated on semiconductor surface. Such radicals are able to degrade several organic compounds. This study used different electrodes and analytical methods for degradation of phenol molecules to reduce treatment costs, improve efficiency, and identify compounds formed during the decomposition of phenolic molecules. Thermal growth of TiO2 film was observed on the titanium electrode in rutile form. Application of an electrical potential on the Ti/TiO2 working electrode increases efficiency in reducing concentration of phenol after photocatalytic treatment. Still, high energy radiation (UVC) showed best degradation rates in photolytic process. Different compounds formed during the degradation of phenol were also identified in the UVC?CPE treatment. 相似文献
113.
I. N. Kurganova V. O. Lopes de Gerenyu J. F. Gallardo Lancho C. T. Oehm 《Eurasian Soil Science》2012,45(1):68-79
The processes of the organic matter (OM) mineralization in forest soils developed under temperate continental (Moscow oblast,
Russia), Mediterranean (the central and western parts of Spain), and tropical monsoon (southern Vietnam) climates were studied
under laboratory conditions. The potential and specific rates of the OM mineralization (PR
min and PR
min/Corg, respectively), the ecophysiological parameters of the microbial communities status (Cmic, qCO2, and Cmic/Corg), and the sensitivity of the rate of the OM mineralization to the rise in temperature were evaluated by the temperature coefficients
(Q
10) determined in the humus horizons (0–10 cm, without forest litter). The average values of PR
min for the climatic zones decreased in the following order: Mediterranean (57.1 ± 10.6 mg C/kg per day) > temperate continental
(23.8 ± 7.1 mg C/kg per day) > tropical monsoon (10.4 ± 1.6 mg C/kg per day). The lowest resistance of the soil OM to mineralization
as evaluated by the PR
min/Corg values was found in the Albeluvisol and Phaeozem of the temperate continental climate and in the Acrisol of the Mediterranean
climate. The highest Q
10 coefficients were attributed to the OM mineralization in the forest soils of the temperate continental climate. This allowed
us to conclude that the observed and expected climate changes with an increase in the mean annual air temperature should lead
to the maximum intensification of the OM mineralization processes in the forest soils of northern regions. 相似文献
114.
Marc Babut Christelle Lopes Sébastien Pradelle Henri Persat Pierre-Marie Badot 《Journal of Soils and Sediments》2012,12(2):241-251
Purpose
Since 2005, freshwater fish contamination by polychlorobiphenyls (PCBs), polychlorodibenzodioxins, and polychlorodibenzofurans has been assessed in the Rhone River basin (France). A large database of surface sediment contamination by PCBs is also available, opening the way to the study of biota-to-sediment accumulation factor (BSAF) distribution throughout this basin. The ultimate goal of the study was to determine a sediment quality guideline (SQG) corresponding to the regulatory fish consumption limit. 相似文献115.
Serão NV Veroneze R Ribeiro AM Verardo LL Braccini Neto J Gasparino E Campos CF Lopes PS Guimarães SE 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2011,128(1):28-34
Seventy-two pigs of three genetic groups (Brazilian indigenous breed Piau, Commercial line and Crossbred) of both sexes were slaughtered at four live weights (30, 60, 90 and 120 kg). Intramuscular fat (IMF) content in Longissimus dorsi muscle of each animal was extracted and correlated with candidate gene mRNA expression (ATN1, EEF1A2, FABP3, LDLR, MGP, OBSCN, PDHB, TRDN and RYR1). Within slaughter weight of 120 kg, Piau and Crossbred pigs showed higher IMF content (p < 0.05) than commercial animals, with 2.48, 2.08 and 1.00% respectively. Barrows presented higher values of IMF (p < 0.05) than gilts (1.54 and 1.30% respectively). Gene expression of EEF1A2, FABP3, LDLR, OBSCN, PDHB, TRDN and RYR1 were correlated with IMF (p < 0.05) using the whole dataset. For Piau data only, expression of FABP3, LDLR, MGP, OBSCN, PDHB, TRDN and RYR1 showed correlation with IMF (p < 0.05). Genes that have important roles in lipid transportation inside the cell (FABP3) and tissues (LDLR) showed correlation with IMF of, respectively, 0.68 and 0.63 using the whole data set, and 0.90 and 0.91 using data from Piau animals. The highly positive correlation of the LDLR and FAPB3 expression with IMF content may confirm that these genes are important for fat deposition in the porcine L. dorsi muscle. 相似文献
116.
Duarte Mde S Paulino PV Valadares Filho Sde C Paulino MF Detmann E Zervoudakis JT Monnerat JP Viana Gda S Silva LH Serão NV 《Tropical animal health and production》2011,43(4):877-886
The effects of two levels of concentrate and ruminally undegradable protein (RUP) on performance, intake, digestibility, carcass
characteristics, meat quality traits, and commercial cuts yield were assessed. Twenty crossbred heifers (240 kg average body
weight) were used. At the beginning of the trial, four animals were slaughtered as reference group and the 16 remaining animals
were randomly assigned to four treatments, in a 2 × 2 factorial design: two levels of concentrate (40% and 80%, dry matter
(DM) basis) and two levels of RUP (48.79% and 27.19% of CP). At the end of the trial, all the animals were slaughtered. There
was no interaction (P > 0.05) between concentrate and RUP levels. Dry matter intake and nutrients digestibility was not affected (P > 0.05) by RUP level. Heifers fed the highest RUP level had greater (P < 0.05) average daily gain (ADG). Concentrate level did not affect (P > 0.05) DMI and ADG. Heifers fed diets with 80% concentrate had greater intake of TDN and EE, and lower intake of NDF (P < 0.05). The digestibilities of all nutrients, except the NDF, were greater (P < 0.05) for the 80% concentrate diets. The RUP levels did not affect (P > 0.05) the carcass characteristics and carcass gain composition. Heifers fed 80% concentrate diets had larger (P < 0.05) longissimus muscle area and lower gain of bones (P < 0.05). Concentrate level did not affect (P > 0.05) the composition of carcass gain. There was no effect (P > 0.05) of RUP and concentrate levels on meat quality traits and commercial cut yields. 相似文献
117.
Soares RM Lopes EG Keid LB Sercundes MK Martins J Richtzenhain LJ 《Veterinary parasitology》2011,175(1-2):168-172
Toxoplasma gondii, Hammondia hammondi, Neospora caninum, Neospora hughesi and Hammondia heydorni are members of the Toxoplasmatinae sub-family. They are closely related coccidians with similarly sized oocysts. Molecular diagnostic techniques, especially those based on polymerase chain reaction (PCR), can be successfully applied for the differentiation of Hammondia-like oocysts. In this paper, we describe a rapid and simple method for the identification of H. heydorni oocysts among other members of the Toxoplasmatinae sub-family, using a heminested-PCR (hnPCR-AP10) based on a H. heydorni RAPD fragment available in molecular database. DNA of oocysts of H. heydorni yielded a specific fragment of 289-290 bp in the heminested-PCR assay. No product was yielded when the primers were used for the amplification of DNA extracted from T. gondii, N. caninum, N. hughesi and H. hammondi, thus allowing the differentiation of H. heydorni among other members of the Toxoplasmatinae sub-family. The hnPCR-AP10 was capable of detecting H. heydorni genetic sequences from suspensions with at least 10 oocysts. In conclusion, the hnPCR-AP10 proved to be a reliable method to be used in the identification of H. heydorni oocysts from feces of dogs. 相似文献
118.
Ivan Carvalho Filho Daniele Botelho Diniz Marques Carolina Filardi de Campos José Domingos Guimarães Simone Eliza Facioni Guimarães Paulo Sávio Lopes Fabyano Fonseca e Silva Renata Veroneze 《Reproduction in domestic animals》2020,55(1):38-43
Nellore is the main cattle breed used in Brazil, being the largest commercial herd in the world. Beyond the importance of male reproductive efficiency for farm profit, the use of reproductive techniques, mainly artificial insemination, turns the evaluation of male reproductive traits even more important. Estimation of genetic parameters increases the knowledge on traits variances and allows envisaging the possibility of the inclusion of new traits as selection criterion. Genetic parameters for fifteen traits that can be classified as testicular biometry or physical and morphological semen traits were estimated for a Nellore bull population ranging from 18 to 36 months. Single-trait and bi-trait animal models were used for (co)variance components estimation. The contemporary group was considered as fixed effect and age at measurement as covariable. Scrotal circumference presented heritability of 0.47 ± 0.12. This value is similar to the heritabilities found for all testicular biometry traits (0.34–0.48). Sperm progressive motility, which has a direct effect on bull fertility, presented low heritability (0.07 ± 0.08). Major and total sperm defects presented moderate to high heritabilities (0.49 ± 0.18 and 0.39 ± 0.15, respectively), indicating that great genetic gain can be obtained through selection against sperm defects. High and positive genetic correlations were observed among testicular biometry traits, which also presented favourable genetic correlations with physical and morphological traits of the semen with magnitude ranging from high to low. Scrotal circumference presented moderate to high and favourable genetic correlations with sperm progressive motility, sperm turbulence, major sperm defects and total sperm defects. Thus, the selection for scrotal circumference results in favourable correlated genetic response for semen quality. The results show that the use of scrotal circumference as reference trait for bull fertility is appropriate, since it presents high heritability and favourable genetic correlation with semen quality. 相似文献
119.
Moura Lais Micaelle Lopes da Silva Pereira Flávia Denise de Lima Patrícia Rodrigues Nascimento Júlio Cesar Silva dos Santos de Oliveira Andresca de Souza Rodrigues Rafael Torres Ferreira Clébio Pereira Moraes Salete Alves Queiroz Mário Adriano Ávila Menezes Daniel Ribeiro 《Tropical animal health and production》2020,52(5):2433-2441
Tropical Animal Health and Production - The aim of this study was to evaluate the effect of adding different concentrations of either urea or NaOH in dehydrated acerola (Malpighia emarginata) fruit... 相似文献
120.
Marcelo Grandi Teixeira José Guilherme Marinho Guerra Dejair Lopes de Almeida Adelson Paulo Araújo Avilio Antonio Franco 《Journal of plant nutrition》2013,36(10):1599-1611
Abstract An experiment was conducted in the greenhouse to evaluate the effects of seed phosphorus (P) concentration on growth, nodulation, and nitrogen (N) and P accumulation of three common bean (Phaseolus vulgaris L.) cultivars. Seeds were produced under low or high soil P levels, and soaked, or not, in 200 mM KH2PO4 solution. The experiment had a 3×3×2×2 factorial block design: three cultivars (ICA Col 10103, Carioca and Honduras 35), three levels of applied P (15, 30 and 45 mg P kg?1 soil), two native seed P concentrations, and two seed soaking treatments. Plants were harvested at flowering. Soaked seeds increased the number, dry mass and P content of nodules, but did not affect plant growth. Plants originated from seeds with high native P concentration presented higher shoot dry mass and nodule number and mass at every soil P level, and were less responsive to increased soil P supply, than plants from low seed P. In plants from seeds with high P, soil P levels did not alter significantly root dry mass, while in plants from seeds with low P bean cultivars expressed wider differences in root dry mass. The genotypic variability of nodulation was influenced by soil P levels and seed P concentration. Both higher soil or seed P supply enhanced N and P accumulation in shoots. These results indicate that a high seed P concentration produces plants less dependent on soil P supply, and can enhance nodulation and N2 fixation of common bean. Seed P supply affected the cultivar performance, and should be considered in evaluation of bean genotypes. 相似文献