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991.
Diabetes is a disease characterized by a hyperglycemic stage that leads to a chronic inflammatory state. We evaluated the in vivo effect of a diet supplemented with 25 % cooked black bean cultivar Negro 8025 (N8025) flour in streptozotocin-induced diabetic rats. The effect was assessed before (preventive-treatment) and after (treatment) the onset of diabetes. There is a significant decrease of total phenolic, tannins and anthocyanins content after cooking, and the concentration of most of the single phenols analyzed are only slightly decreased. The treatment group showed a significant reduction of glucose (22.8 %), triglycerides (21.9 %), total cholesterol (29.9 %) and LDL (56.1 %) that correlates with a protection of pancreatic ß-cells. The diet with N8025 flour before the induction of diabetes did not exert a protective effect (glucose levels are similar to the diabetic control) but they have low levels of total cholesterol (47.5 %) and LDL (56.1 %). The preventive-treatment group did not inhibit the increase of TNF-α and IL-1β, whereas the treatment group did, compared to the diabetic control. Therefore, N8025 bean supplementation can be recommended to control diabetes.  相似文献   
992.
Human consumption of flaxseed is increasing due to its health benefit properties and extrusion processes can enhance its nutritional quality. Extruded flaxseed meal (EFM) obtained in a pilot plant was characterized and incorporated in flour mixes and cereal-based bars to demonstrate its nutritious usefulness. Amino acid content was not affected by extrusion and, despite lysine was the limitating amino acid, the chemical score (CS) was 83 %. Thiamin and riboflavin decreased slightly as consequence of extrusion, phytic acid did not change and trypsin inhibitor activity was undetectable. Proximate composition and nutritional quality determined by biological and chemical indexes were compared among EFM, flour mixes (FM) and cereal bars (CB). They presented high protein levels (26, 20 and 17 %, respectively), good biological value (BV) (80, 79 and 65, respectively), acceptable true protein digestibility (TD) (73, 79 and 78, respectively), and high dietary fiber (33, 20.5 and 18 %, respectively). The ratio of ω6:ω3 for CB was within the WHO/FAO recommendations. These results open a new venue for the usefulsess of nutritious/healthy extruded flaxseed flours into ready-to-eat cereal-based products with improved nutritional quality.  相似文献   
993.
Several reports have focused on utilization of post-harvest residues of crops, while neglecting those residues produced by mango processing. These residues represent a waste of nutrients and a source of environmental contaminants. Such by-products could be valuable sources of dietary fiber (DF), antioxidant compounds, and single carbohydrates. The aim of this study was to evaluate some functional properties (FP), and the content of DF and polyphenols (PP) of the peel and coarse material obtained from residues during the industrial processing of Ataulfo and Tommy Atkins mangoes. The total dietary fiber (TDF) content was about 225 mg/g and 387 mg/g (dry weight) for the coarse material and the peel, respectively, from which soluble dietary fiber represented 23 and 42 %, respectively. The main neutral sugar identified was rhamnose, especially in peels; the klason lignin (KL) content was 92 mg/g, which highlights the Ataulfo peel (Ataulfo-P) and the Tommy Atkins peel (Tommy Atkins-P). The extractable PP content in Ataulfo-P was higher than in Tommy-Atkins-P, and interesting data for non-extractable PP were obtained in the residues. FP as swelling, water holding, oil holding, and glucose absorption in the residues was studied, obtaining better functional properties when compared to cellulose fiber. The results show that mango industrial by-products, mainly from the Ataulfo-P variety, could be used as ingredients in food products because of their functional properties as well as their DF and PP content.  相似文献   
994.
A study was conducted to investigate the presence of Cryptosporidium and Giardia in Antarctic marine mammals. A total of 270 faecal samples from different species of pinnipeds from different locations in the South Shetland Islands and Antarctic Peninsula were analysed by immunofluorescence microscopy and PCR. Cryptosporidium was detected by PCR in three samples from Southern elephant seals (Mirounga leonina) and 2 Weddell seals (Leptonychotes weddellii). However, no oocysts were observed in any of the samples by immunofluorescence microscopy. Molecular characterisation of the isolates, using the 18S rDNA, the HSP70 and the COWP loci, revealed the presence of a Cryptosporidium sp., previously reported from an Antarctic Southern elephant seal, in the elephant seals and a novel genotype in Weddell seals. Giardia could not be detected in any of the samples analysed.  相似文献   
995.
The ovine brucellosis caused by Brucella ovis has tropism for reproductive tissues but until now the mechanism of bacterial persistence is not understood. Cytokine expression profiles were studied for 8 months in rams after being experimentally infected with the rough virulent strain of B. ovis (R-B. ovis) to study the pathogenesis of B. ovis and immune mechanism possibly associated to bacteria tropism and persistence. The messenger RNA (mRNA) expression levels of interleukin-1α (IL-1α), IL-1β, IL-6, IL-10, IL-12, interferon-γ (INF-γ) and tumour necrosis factor-α (TNF-α) cytokines were quantified by real-time quantitative RT-PCR (qRT-PCR) in reproductive tissues (epididymus, testicles, ampolae, vesicular glands and bulbourethral glands), and non-reproductive (liver, spleen and kidneys) tissues at 30, 60, 120 and 240 days post infection (dpi). During the acute phase of infection at 30 dpi, the host immune response was most notable demonstrating an up-regulation of several cytokines in reproductive tissues, including the epididymus (IL-6, IL-1β and IL-1α), testicles (INF-γ and IL-12), bulbourethral glands (IL-6 and TNF-α) and ampolae (INF-γ, IL-10, IL-1β and IL-1α). During the development of infection, cytokine gene expression levels decreased, providing evidence of immunosuppression and evidence of immune evasion that favoured persistence of chronic R-B. ovis infection. During the chronic phase of R-B. ovis infection (120 and 240 dpi), cytokine production was down-regulated in the epididymus (IL-1β and IL-1α), testicles (INF-γ and IL-12), and ampolae (INF-γ, IL-10, IL-1β and IL-1α), with the exception of the bulbourethral glands (IL-6 and TNF-α) and epididymus (IL-6); in these tissues, R-B. ovis infection resulted in up-regulation of the pro-inflammatory cytokine IL-6. Herein, we report cytokine expression profiles in tissues of rams experimentally infected with the rough strain of B. ovis, which are associated with bacterial persistence and macrophage activation.  相似文献   
996.
Data from a divergent experiment for birthweight (BrW) environmental variability were used to estimate genetic parameters for BrW trait and its environmental variability by fitting both homoscedastic (HO) and heteroscedastic (HE) models. A total of 5 475 records of BrW from animals born from inbred dams, and 7 140 pedigree records were used. The heritability of BrW using the model HO was 0.27, with the litter effect much more important, 0.43. The model HE provided a genetic correlation between the trait and its environmental variability that was very high and negative, ?0.97, and a high value for the additive genetic variance for environmental variability, suggesting an artefact in the model. The residual skewness was found to be essentially null. A model considering the genetic correlation null was also fitted, and used to obtain the breeding values for the selection process. Moreover, the trait was considered as maternal resulting in similar estimates under the model HO, but more reasonable for the genetic correlation between the trait and its environmental variability of 0.48 with a value of 0.25 for the additive genetic variance regarding environmental variability under the model HE. This led to the conclusion that environmental variability of BrW in mice must be selected via dams. Estimated parameters in a reduced dataset without inbred animals did not substantially change this conclusion.  相似文献   
997.
A reliable indication of pollen fertility is the number of seeds per fruit produced following artificial pollination, but this method is laborious, and very slow because sampling needs ripe fruits. To seek faster techniques to test the fertility of tomato pollen produced at low temperatures, we cultivated a large collection of tomato cultivars and lines of related wild species under cold conditions with minimum nocturnal temperatures below 10°C. We compared numbers of seeds per fruit with: number of pollen tubes at the base of the style, index of natural fruit-set, percentage of pollen grains stained with acetocarmine, percentage of pollen grains giving fluorochromatic reaction with fluoresceine diacetate, and percentage of pollen grains which germinated in vitro. All these variates correlated positively and significantly between themselves. The number of pollen tubes at the base of the style most closely correlated with number of seeds. This technique is equally laborious, but is good for precise testing of small numbers of genotypes and results are quickly available. Both acetocarmine staining and fluorochromatic reaction were simple, fast techniques with potential for screening large collections to detect genotypes with highly fertile pollen at low temperature; acetocarmine was the best, but neither test would identify genotypes with low-fertile pollens. Index of natural fruit-set and germination in vitro did not effectively determine the fertility of pollen produced at low temperature.  相似文献   
998.
999.

Deltamethrin, a pyrethroid insecticide, was tested in both the laboratory and the field, with the aim of controlling the olive bark beetle, Phloeotribus scarabaeoides (Bernard), in living olive trees. In the laboratory, bark beetle adults were exposed to olive twigs treated with different concentrations of deltamethrin. Among these concentrations, dosage at 0.05% produced 100% mortality in the scolytids after 13 weeks. This dosage of deltamethrin, applied in the field, protected olive trees from scolytid attack during the whole emergence period.  相似文献   
1000.
Avocado processing by the food and cosmetic industries yields a considerable amount of phenolic-rich byproduct such as peels and seeds. Utilization of these byproducts would be favorable from an economic point of view. Methanolic (80%) extracts obtained from lyophilized ground peels and seeds of avocado (Persea americana Mill.) of the Hass and Shepard varieties were characterized for their phenolic compound profiles using the HPLC-PAD technique. The structures of the identified compounds were subsequently unambiguously confirmed by ESI-MS. Compositional analysis revealed that the extracts contained four polyphenolic classes: flavanol monomers, proanthocyanidins, hydroxycinnamic acids, and flavonol glycosides. The presence of 3-O-caffeoylquinic acid, 3-O-p-coumaroylquinic acid, and procyanidin A trimers was identified in seeds of both varieties. Intervarietal differences were apparent in the phenolic compound profiles of peels. Peels of the Shepard variety were devoid of (+)-catechin and procyanidin dimers, which were present in the peels of the Hass variety. Peels of both varieties contained 5-O-caffeoylquinic acid and quercetin derivatives. The differences in the phenolic profiles between varietals were also apparent in the different antioxidant activity of the extracts. The peel extracts had a higher total phenolic compound content and antioxidant activity when compared to the seed extracts. The highest TEAC and ORAC values were apparent in peels of the Haas variety in which they amounted to 0.16 and 0.47 mmol Trolox/g DW, respectively. No significant (p > 0.05) differences were apparent between the TEAC values of seeds of the two varieties but the ORAC values differed significantly (p < 0.05). Overall these findings indicate that both the seeds and peel of avocado can be utilized as a functional food ingredient or as an antioxidant additive.  相似文献   
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