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81.
Corkwing wrasse, Symphodus melops, is one of the main species used as cleaner fish to combat sea lice infestation in salmon aquaculture; however, there is little knowledge about its biology. Here, we describe the embryonic development of this species and examine the viability of the eggs under three temperature regimes. The experiments were conducted at three water temperature regimes, 12, 15, and 18°C, which resemble common sea water temperatures registered during the spawning season of corkwing wrasse at different latitudes along the Norwegian coast. Corkwing wrasse spawn small spherical eggs of 0.75–0.80 mm in diameter (mean 0.78, CV = 3.6%) with several oil droplets and go through eight developmental stages until hatching. The shortest hatching time was registered after 144 hr at 18°C and after 222 and 372 hr at 15 and 12°C, respectively. These observations provide important baseline biological information to advance the establishment of commercial rearing techniques and sustainable fishing management practices for this heavily exploited species.  相似文献   
82.
Fisheries Science - A correction to this paper has been published: https://doi.org/10.1007/s12562-021-01502-z  相似文献   
83.
The fatty acid profile of the subcutaneous fat of pigs and its evolution throughout fattening as affected by dietary conjugated linoleic acid (CLA), monounsaturated fatty acids (MUFA), and their interaction (CLAxMUFA) were studied. Three levels (0, 1, and 2%) of an enriched CLA oil (28% cis-9, trans-11 and 28% trans-10, cis-12 CLA) were combined with two levels of MUFA (low, 19% average; and high, 39% average) for pig feeding (288 gilts). Subcutaneous shot-biopsies were taken from 48 animals at the beginning of the trial (S1, 70 kg), 14 days later (S2, 80 kg), and at slaughter (S3, 107 kg). Inclusion of CLA in the diet caused an increase during fattening in cis-9, trans-11 CLA, trans-10, cis-12 CLA, and saturated fatty acids (SFA) contents of pig backfat and a decrease in MUFA and polyunsaturated fatty acids (PUFA). MUFA supplementation also led to a MUFA enrichment of backfat. The interaction CLAxMUFA affected the SFA content. The rates of accumulation of CLA isomers, SFA, and MUFA throughout the trial did not follow a linear behavior, such rates being higher from S1 to S2 than from S2 to S3. These rates were also influenced by dietary CLA and MUFA levels. The increase in the ratio of saturated to unsaturated fatty acids of backfat caused by dietary CLA might be balanced by supplementation of pig diets with MUFA.  相似文献   
84.
The effects of two exogenous fibrolytic enzyme products on ruminal disappearance and fermentation of oat straw-wheat middlings based diets were evaluated. Six steers (322 ± 34.4 kg body weight) fitted with ruminal cannulas were used in a 3 × 3 Latin square replicated. The treatments consisted of: 1) control, 2) Fibrozyme (2 g/kg dry matter), and 3) Promote (3 ml/kg dry matter). Both, Fibrozyme (Alltech Inc.) and Promote NET (Cargill Corp.) were sprayed as liquid onto diets and feeds 24 h before feeding. Samples of diets were ruminally incubated from 0 to 72 h. Enzymes did not change dry matter intake, average daily gain and feed conversion. Fibrozyme increased crude protein (CP) disappearance rate of diet, while Promote increased CP total disappearance. In diets, enzymes did not affect ruminal neutral detergent fiber (NDF) and acid detergent fiber (ADF) fractions. Fibrozyme and Promote did increase CP total disappearance, ADF potential disappearance and ADF disappearance rate of wheat middlings, as well as dry matter (DM) and CP total disappearance, NDF disappearance rate, ADF potential disappearance and ADF disappearance rate of oat straw. Ruminal pH values were higher with enzymes, as compared to control. Total volatile fatty acids concentration and molar proportion of acetate and butyrate were not affected by both enzymes, but molar proportion of propionate was lower and acetate:propionate ratio higher with Promote than control. Fibrozyme and Promote did increase DM and CP soluble fractions of diets, as well as, ADF potential disappearance of wheat middling and oat straw.  相似文献   
85.
A pig was in left lateral recumbency with limb spasticity, accentuated prostration, and strabismus, and was euthanized. During autopsy, yellowing of the leptomeninges at the ventral pons to medulla oblongata was noted. In the cerebellar peduncles, there was a focally extensive black-to-yellow area at the level of the vestibular nuclei. Histologic examination revealed a cross-section of a nematode larva, consistent with Stephanurus dentatus, bordered by edema and marked infiltration of mononuclear cells, plasma cells, and a few eosinophils. Vacuolation of the neuropil, with rare gitter cells and axonal spheroids, was also observed. We diagnosed parasitic encephalitis caused by S. dentatus migration based on the pathology findings and characterization of the parasite.  相似文献   
86.
Activated sodium peroxydisulfate has the potential to in situ destruct many organic contaminants because of the generation of the stronger oxidant sulfate radical. From photochemical activation of peroxydisulfate in flash-photolysis experiments, the bimolecular rate constants for the reaction of sulfate radical with glyphosate (1.6 × 10(8) M(-1) s(-1)) and paraquat (1.2 × 10(9) M(-1) s(-1)) at 25 °C were obtained. Thermal activation of peroxydisulfate was shown to degrade the herbicides clomazone, paraquat, and glyphosate. Although the herbicide degradation was observed to take place in less than 1 h, the mineralization of the organic carbon required longer reaction times, because of the formation of stable organic intermediates. For similar initial total organic carbon (TOC) values, TOC profiles were similar for experiments with different substrates (the herbicides, humic acids, and a mixture of glyphosate and humic acids), which indicates that the mineralization of all of the samples is limited by the production of SO(4)(?)?(-) radicals. A linear correlation between the initial amount of SO(4)(?)?(-) needed per mole of C and the average oxidation state was found.  相似文献   
87.
A Taenia saginata oncosphere-derived adhesion protein (HP6) with surface and secreted localization was used to successfully vaccinate calves against oral challenge with T. saginata eggs. In contrast, vaccination using a combination of T. saginata oncosphere-derived peptides, selected on the basis of their antigenic index, and including three derived from the HP6 molecule (HP6-1, HP6-2 and HP6-3), was unsuccessful. This either indicated that the wrong peptides were selected or, in the case of the HP6 protein, that the protective epitope is conformational in nature. The protection experiments were monitored using a parasite antigen detection ELISA (HP10 Ag-ELISA), which allowed the early determination of the success of the vaccination protocol, subsequently confirmed at autopsy. PCR assays were used for the first time to confirm the presence of T. saginata DNA in lesions recovered at autopsy and thus verify the parasite origin of the lesions.  相似文献   
88.
Infection with a retrovirus, Jaagsiekte sheep retrovirus (JSRV), causes ovine pulmonary adenocarcinoma (OPA). The excess production of surfactant proteins by alveolar tumour cells results in increased production of pulmonary fluid, which is characteristically expelled through the nostrils of affected sheep. The immune response to JSRV and the tumour is poorly understood: no JSRV-specific circulating antibodies or T cells have been detected to date. The aim of the present study was to obtain phenotypic evidence for a local immune response in OPA lungs. Specific-pathogen free lambs were infected intratracheally with JSRV. When clinical signs of OPA were apparent, the lungs were removed at necropsy and immunohistochemistry (IHC) was performed on lung sections using a panel of mouse anti-sheep mAbs. No influx of dendritic cells, B cells, CD4, CD8 or gammadelta T cells was seen in the neoplastic nodules or in their periphery. MHC Class II-positive cells were found intratumourally, peritumourally and in the surrounding alveolar lumina. In the tumours, many of these cells were shown to be fibroblasts and the remainder were likely to be mature macrophages. In the alveolar lumen, the MHC Class II-positive cells were CD14-positive and expressed high levels of IFN-gamma. They appeared to be immature monocytes or macrophages which then differentiated to become CD14-negative as they reached the periphery of the tumours. A high level of MHC Class I expression was detected on a range of cells in the OPA lungs but the tumour nodules themselves contained no MHC Class I-positive cells. On the basis of these findings, it is proposed that the lack of an effective immune response in OPA could result from a mechanism of peripheral tolerance in which the activity of the invading macrophages is suppressed by the local environment, possibly as a consequence of the inhibitory properties of the surfactant proteins.  相似文献   
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