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91.
Naldoni J Arana S Maia AA Silva MR Carriero MM Ceccarelli PS Tavares LE Adriano EA 《Veterinary parasitology》2011,177(3-4):247-255
A new myxosporean species, Henneguya eirasi n. sp., is described parasitizing the gill filaments of Pseudoplatystoma corruscans and Pseudoplatystoma fasciatum (Siluriformes: Pimelodidae) caught in the Patanal Wetland of the state of Mato Grosso, Brazil. The parasite formed white, elongated plasmodia measuring up to 3mm. Mature spores were ellipsoidal in the frontal view, measuring 37.1 ± 1.8 μm in total length, 12.9 ± 0.8 μm in body length, 3.4 ± 0.3 μm in width, 3.1 ± 0.1 μm in thickness and 24.6 ± 2.2 μm in the caudal process. Polar capsules were elongated and equal in size, measuring 5.4 ± 0.5 μm in length and 0.7 ± 0.1 μm in width. Polar filaments had 12-13 coils. Histopathological analysis revealed that the parasite developed in the sub-epithelial connective tissue of the gill filaments and the plasmodia were surrounded by a capsule of host connective tissue. The plasmodia caused slight compression of the adjacent tissues, but no inflammatory response was observed in the infection site. Ultrastructure analysis revealed a single plasmodial wall connected to the ectoplasmic zone through numerous pinocytotic canals. The plasmodial wall exhibited numerous projections and slightly electron-dense material was found in the ectoplasm next to the plasmodial wall, forming a line just below the wall. Partial sequencing of the 18S rDNA gene of H. eirasi n. sp. obtained from P. fasciatum resulted in a total of 1066 bp and this sequence did not match any of the Myxozoa available in the GenBank. Phylogenetic analysis revealed the Henneguya species clustering into clades following the order and family of the host fishes. H. eirasi n. sp. clustered alone in one clade, which was the basal unit for the clade composed of Henneguya species parasites of siluriform ictalurids. The prevalence of the parasite was 17.1% in both fish species examined. Parasite prevalence was not influenced by season, host sex or host size. 相似文献
92.
Gordon A Jungfer E da Silva BA Maia JG Marx F 《Journal of agricultural and food chemistry》2011,59(14):7688-7699
The Amazon region comprises a plethora of fruit-bearing species of which a large number are still agriculturally unimportant. Because fruit consumption has been attributed to an enhanced physical well-being, interest in the knowledge of the chemical composition of underexplored exotic fruits has increased during recent years. This paper provides a comprehensive identification of the polyphenolic constituents of four underutilized fruits from the Amazon region by HPLC/DAD-ESI-MS(n). Arac?a? ( Psidium guineense ), jambola?o ( Syzygium cumini ), muruci ( Byrsonima crassifolia ), and cutite ( Pouteria macrophylla ) turned out to be primarily good sources of hydrolyzable tannins and/or flavonols. Additionally, different flavanonols and proanthocyanidins were identified in some fruits. The antioxidant capacity was determined by using the total oxidant scavenging capacity (TOSC) assay. Cutite showed the highest antioxidant capacity followed by jambola?o, arac?a?, and muruci. 相似文献
93.
RJ Schoelkopf P Wahlgren AA Kozhevnikov P Delsing DE Prober 《Science (New York, N.Y.)》1998,280(5367):1238-1242
A new type of electrometer is described that uses a single-electron transistor (SET) and that allows large operating speeds and extremely high charge sensitivity. The SET readout was accomplished by measuring the damping of a 1.7-gigahertz resonant circuit in which the device is embedded, and in some ways is the electrostatic "dual" of the well-known radio-frequency superconducting quantum interference device. The device is more than two orders of magnitude faster than previous single-electron devices, with a constant gain from dc to greater than 100 megahertz. For a still-unoptimized device, a charge sensitivity of 1.2 x 10(-5) e/hertz was obtained at a frequency of 1.1 megahertz, which is about an order of magnitude better than a typical, 1/f-noise-limited SET, and corresponds to an energy sensitivity (in joules per hertz) of about 41 Planck's over 2pi. 相似文献
94.
95.
Maria Ivanilda de Aguiar Stoécio Malta Ferreira Maia Francisco Alisson da Silva Xavier Eduardo de Sá Mendonça João Ambrósio Araújo Filho Teógenes Senna de Oliveira 《Agroforestry Systems》2010,79(3):277-289
Inadequate soil management practices adopted in the Brazilian semi-arid region contribute to erosive processes. Agroforestry
systems (AFs) have been considered an alternative to reduce water erosion. This study aimed to evaluate the impact of two
alternatives AFs, a traditional and an intensive cropping system on the losses of sediments, water, organic carbon and nutrients
caused by water erosion in comparison to the natural vegetation (caatinga) in a semi-arid region of northeastern Brazil. The
agroecosystems studied were: agrosilvopasture (AGP) which consisted of an alley cropping system, cultivated with Leucaena leucocephala and maize, within an area composed by 22% of native trees (200 native trees per hectare) which was grazed during the dry
season; silvopasture (SILV) that was composed by 38% of native trees (260 trees per hectare) with a stocking rate of 20 ewes
during whole year; traditional agrosilvopasture (TRAG) being managed as following: total deforestation, burning of the residues,
cropped with maize for 2 years (1998 and 1999) and fallow during 8–10 years; and intensive cropping (IC) system which was
deforested and burned in 1997 followed by cultivation of maize from 1998 to 2002, and thereafter by a fallow period of 8–10 years
similar to TRAG. Two areas of native forest (NF1, NF2) known as ‘caatinga’, used as grassland during the dry season and as
a source of wood, were selected and used as reference of steady state in the comparative study in relation to the cultivated
sites. Sediment and water losses as a result of erosion were collected during two rainy seasons, i.e. 2003 and 2004, and nutrients
and organic carbon contents were determined. Soil samples were collected and organic carbon, pH in water, pH in KCl, water
dispersible clay (WDC) and hydraulic conductivity (K0) were measured. In 2003, sediment and water losses did not differ significantly among all treatments. However, in 2004, TRAG
(0.70 Mg ha−1) and NF1 (1.37 Mg ha−1) showed the highest sediment losses, whereas TRAG and IC presented the highest water losses. On average, nutrients losses
in cropped areas were lower than in natural vegetation (NF1, NF2). The alternative AFs (AGP, SILV) were efficient to reduce
water erosion effects when compared to the most common agricultural practices adopted in the region, being highly recommended
as sustainable technical alternatives for food production in the region. 相似文献
96.
F.J.N. Maia V.G.P. RibeiroD. Lomonaco F.M.T. LunaS.E. Mazzetto 《Industrial Crops and Products》2012,36(1):271-275
This work describes the synthesis and study of the antioxidant activity in mineral oils of new thiophosphorylated compound derived from cashew nut shell liquid (CNSL), a by-product of the process of improvement of cashew nuts. This study was conducted through the thermal analysis observing the Tonset variations and the accelerated oxidation experiments observing the induction time variations. The results of thermogravimetric and acceleration oxidative experiments showed a significant improvement in the oxidative stability of the doped oils. These results suggest that this new compound acts efficiently in the stabilization of the naphthenic mineral oils. 相似文献
97.
Regina Coimbra Rola Luis Fernando Marins Luiz Eduardo Maia Nery Carlos Eduardo da Rosa Juliana Zomer Sandrini 《Fish physiology and biochemistry》2014,40(6):1817-1825
Fish are commonly exposed to environmental pollutants, which in turns could induce an oxidative stress. So, it is important to understand the effects and the responses elicited by these toxicants in fish species, being fish cell lines important tools for this purpose. Thus, the aim of the present study was to compare the effects of copper and UV-B radiation exposure on zebrafish hepatocytes (ZFL lineage) in terms of reactive oxygen species (ROS) levels, sulfhydril groups content and mRNA levels of important genes related to cellular response to toxic agents. Exposure of ZFL cells to UV-B radiation (23.3 mJ/cm2) significantly increased levels of intracellular ROS and mRNA of both superoxide dismutase isoforms (sod1 and sod2), three glutathione S-transferase isoforms (gstα, gstµ and gstπ) and a heat shock protein (hsp70). However, no changes in nonprotein sulfhydryl groups (NP-SH) content, as well as in the mRNA levels of genes related to glutathione (GSH) synthesis and recycling, were observed. Contrary to this, copper exposure (20 mg/L) diminished NP-SH content and increased the levels of mRNA of genes related to GSH synthesis (gclc and gs). Moreover, copper exposure increases the mRNA levels of some genes related to antioxidant defenses (gpx and gstπ), biotransformation reactions (cyp1a1) and protein repair (hsp70). In conclusion, these results demonstrated that both toxicants could increase ROS levels in ZFL cell line, but the responses are different, which could be related to activation of different signaling pathways. 相似文献
98.
Iraci Sinski Daniela Dal Bosco Neiva Izabel Pierozzi João Dimas Garcia Maia Patrícia Silva Ritschel Vera Quecini 《Euphytica》2014,196(2):299-311
The efficiency of in vitro polyploidization depends on several variables associated to the plant, the antimicrotubule agent and the interactions between them. In the present work, we have used response-surface methodology to determine the best operating conditions for plant recovery in polyploidization assays for shoot apices and somatic embryos of two seedless grape cultivars, employing colchicine and oryzalin. Explant type, tubulin-interfering compound and concentration were the critical factors determining plant recovery. Linear reduction in viable plant regeneration via organogenesis and somatic embryogenesis was obtained by increasing oryzalin concentrations and treatment time, whereas the effects of colchicine were better described by a quadratic design for both explants types. The conditions promoting higher rates of plant recovery were used in chromosome doubling experiments with oryzalin and colchicine for shoot apices and somatic embryos of ‘Crimson seedless’ and ‘BRS Clara’. The established protocols allowed the recovery of non-chimerical autotetraploid plants at rates higher than 30 % for both cultivars. Stomata size parameters statistically correlate to the ploidy level of the regenerants and were effective for preliminary polyploidy screening. Autotetraploid lines of seedless grapes were incorporated into the Vitis germplasm bank for further agronomical evaluations. To our knowledge, this is the first report of in vitro oryzalin induced polyploidization of grapevine and of the use of mathematical modeling to optimize chromosome doubling in plants. 相似文献
99.
Julimar do Sacramento Ribeiro Luana Lira Santos Dorgival Morais de Lima Júnior Tobyas Maia de Albuquerque Mariz Márcio Machado Ladeira Paulo Sérgio de Azevedo Carolyny Batista Lima Maria Josilaine Matos dos Santos Silva 《Tropical animal health and production》2017,49(5):995-1000
The effect of the replacement of corn silage with spineless cactus associated with Tifton 85 hay or sugarcane bagasse was evaluated on the performance, body weight components and sheep meat quality. Twenty-one Santa Inês male sheep with initial body weight of 22.9 ± 2.9 kg were used. They were confined in individual stalls for 74 days receiving the following diets: corn silage + concentrate (CS); spineless cactus + Tifton 85 hay + concentrate (TH); spineless cactus + sugarcane bagasse + concentrate (SB). After the feedlot period, the animals were slaughtered and their body components were weighed and sampled. Data were submitted to Tukey’s test at 5% probability. The average daily gain (0.25 vs 0.14 kg), cold carcass weight (13.3 vs 13.7 kg), loin muscularity (0.6 vs 0.4 kg) and liver weight (0.7 vs. 0.5 kg) were higher (P < 0.05) for the TH diet when compared to that for the CS. The physical-chemical parameters of meat were not influenced (P > 0.05) by the treatments and presented about 20.1% of crude protein, 6.1% of crude fat and shear force of 2.0 kgf/cm2. In complete diets for sheep, Tifton 85 hay associated with spineless cactus provides greater weight gain, cold carcass muscularity and organ weight when compared to those for animals fed with corn silage as exclusive roughage. Sugarcane bagasse associated with spineless cactus may replace corn silage in complete diets for sheep. 相似文献
100.
Maia Lesosky Sarah Dumas Ilana Conradie Ian Graham Handel Amy Jennings Samuel Thumbi Phillip Toye Barend Mark de Clare Bronsvoort 《Tropical animal health and production》2012,45(1):311-316
The accurate estimation of livestock weights is important for many aspects of livestock management including nutrition, production and appropriate dosing of pharmaceuticals. Subtherapeutic dosing has been shown to accelerate pathogen resistance which can have subsequent widespread impacts. There are a number of published models for the prediction of live weight from morphometric measurements of cattle, but many of these models use measurements difficult to gather and include complicated age, size and gender stratification. In this paper, we use data from the Infectious Diseases of East Africa calf cohort study and additional data collected at local markets in western Kenya to develop a simple model based on heart girth circumference to predict live weight of east African shorthorn zebu (SHZ) cattle. SHZ cattle are widespread throughout eastern and southern Africa and are economically important multipurpose animals. We demonstrate model accuracy by splitting the data into training and validation subsets and comparing fitted and predicted values. The final model is weight0.262?=?0.95?+?0.022 × girth which has an R 2 value of 0.98 and 95 % prediction intervals that fall within the ±20 % body weight error band regarded as acceptable when dosing livestock. This model provides a highly reliable and accurate method for predicting weights of SHZ cattle using a single heart girth measurement which can be easily obtained with a tape measure in the field setting. 相似文献