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91.
Soil structure is a key indicator for soil quality. Often, a degradation of the soil structure is the result of inappropriate land management. This investigation was carried out in the Western Siberian forest steppe, because soil degradation is an important issue in this part of the Siberian Grain Belt. Therefore, soil structure and further soil properties were examined in the vicinity of the city of Tyumen, Russia. Arable and non‐arable sites were compared by means of the soil fingerprint code (SFC). With SFC the soil surface conditions, chemical and physical parameters of the topsoil were recorded and evaluated in two depths: 0–5 cm and 5–30 cm. The suitability of the SFC to quantify changes of the soil structure of the topsoil was tested. The SFCs of arable and non‐arable sites show that soil structure deteriorates due to arable use. The percentage of granular aggregates decreases and the percentage of subangular blocky and angular blocky aggregates increases. Furthermore, ploughing leads to strong clod formation. Differences in soil structure between 0–5 cm and 5–30 cm soil depth were smaller at arable sites in comparison to non‐arable sites. It was ascertained the SFC is suitable to quantify changes of the soil structure.  相似文献   
92.
Verticillium wilt is a devastating disease in hops and causes considerable crop losses. V. albo-atrum is the most widespread species, whereas V. dahliae is rarely found. Due to the survival of the fungus for several years in soil by resting structures and the lack of effective chemical control, a fast detection method is needed. One aim of this study was to evaluate the occurrence of Verticillium spp. in the Hallertau region (Germany). Therefore, 76 hop plants, with or without wilt symptoms, were analyzed using a real time PCR (polymerase chain reaction) assay. V. albo-atrum was identified in 57 bine samples. The pathogen can sporadically appear without showing visual symptoms. The abundance of the fungus inside the plants was analyzed. Furthermore, four beneficial bacteria, Burkholderia terricola ZR2-12, Pseudomonas poae RE*1-1-14, Serratia plymuthica 3Re4-18, and Stenotrophomonas rhizophila DSM14405T, were evaluated as biological control agents in hops. The colonization competence in the root system, plant growing promotion, and antagonistic effects were assessed. All strains colonized the endorhiza and the rhizosphere. The bacterial strains B. terricola ZR2-12, S. plymuthica 3Re4-18, and S. rhizophila DSM14405T are promising candidates for further biocontrol strategies. Thus, first steps towards the biological control of Verticillium wilt were presented.  相似文献   
93.
OBJECTIVE: To evaluate time-dependent alterations in gene expression of chemokines in bronchial epithelium of recurrent airway obstruction (RAO)-affected horses and whether alterations resulted from increases in gene expression of interleukin (IL)-17 in cells isolated from bronchoalveolar lavage fluid (BALF). ANIMALS: 8 RAO-susceptible horses and 9 control horses. PROCEDURE: In 2 experiments, both groups of horses were evaluated after being maintained on pasture and after being stabled and fed dusty hay for 1, 14, 35, and 49 days (experiment 1) or 14 and 28 days (experiment 2). In experiment 1, gene expression of IL-8, chemokine (C-X-C motif) ligand 1 (CXCL1), granulocyte-macrophage colony-stimulating factor (GM-CSF), granulocyte colony-stimulating factor (G-CSF), and Toll-like receptor 4 (TLR4) in epithelium and IL-8, IL-17, and TLR4 in BALF cells was measured. In experiment 2, bronchial biopsy specimens were evaluated for IL-8 immunoreactivity. RESULTS: In RAO-susceptible horses after 14 days of challenge exposure, there was a 3- and 10-fold increase in gene expression of IL-8 for epithelial and BALF cells and an increase in IL-8 immunoreactivity in epithelial cells. Challenge exposure failed to alter gene expression of CXCL1, GM-CSF, G-CSF, and TLR4 in epithelial cells of any horses at any time point. During challenge exposure, gene expression of BALF cell IL-17 was downregulated in control horses (day 1) and upregulated in RAO-affected horses (day 35). CONCLUSIONS AND CLINICAL RELEVANCE: Epithelial-derived IL-8 may promote airway neutrophilia, but the inciting stimulus is unlikely to be IL-17 because upregulation of this gene is subsequent to that of IL-8 in epithelial cells.  相似文献   
94.
Interest in new sources of anti-inflammatory and antioxidant compounds has recently become a major research issue, with the cornelian cherry (Cornus mas L.) receiving particular attention for its significant amounts of phenolic compounds and vitamins, which exhibit a wide range of biological and pharmacological properties. This study was aimed at increasing knowledge regarding the cornelian cherry in Italy through the analysis of biologically active substances in the locally available genotype “Chieri”. Spectrophotometric methods were applied to evaluate antioxidant activity, total anthocyanin content and total polyphenolic content. Identification and quantification of the main phytochemical compounds (polyphenols, monoterpenes, organic acids and vitamin C) was performed via high performance liquid chromatography coupled to a diode array detector. C. mas extracts showed high levels of total soluble solids and low acidity. High amounts of phenolic secondary metabolites were observed, with particular reference to anthocyanins (134.71 mgC3G/100 gFW), which confer remarkable nutraceutical properties to the analysed samples. These results highlight the potential of C. mas fruits as a good source of natural antioxidants, suggesting their use as a functional food. Future studies should focus on identifying other specific phytochemical compounds and the genetic traits of local varieties in order to improve cornelian cherry cultivars for food and medicine production.  相似文献   
95.
Grape varieties with resistance to downy mildew (DM) carry alien chromosome segments in Vitis vinifera backgrounds. We previously showed that the largest descent group shares a non‐vinifera haplotype at the locus Rpv3. Here, we performed a common garden experiment with 76 varieties to evaluate the level of field resistance across four years. All varieties exhibited effector‐triggered immunity (ETI)‐associated necrosis. On a scale of 1–9, the median OIV452 value for foliar resistance was 7.1 in the resistant lineage vs. 3.2 in vinifera controls. Genotype, year and their interaction significantly affected the level of resistance. Some resistant genotypes showed high mean values of OIV452 and low variance among years. Other resistant genotypes showed lower mean OIV452 and higher variance. They were capable of activating ETI, but the intensity was inadequate to restrict pathogen growth under highly conducive conditions. Rpv3‐dependent responses were stronger in highly native genetic backgrounds and tended to attenuate in late backcross generations. Genetic backgrounds donated by European winegrapes of the convarietas occidentalis provided on average higher levels of Rpv3 resistance than backgrounds of orientalis table grapes.  相似文献   
96.
<正>水便综合征对家禽生产造成的的影响是巨大的。除了疾病,饲料质量、垫料和环境温度,包括通风都对粪便质量产生影响。其中,饲料的影响是主要因素之一。非淀粉多糖酶早就作为饲料添加剂应用于改善水便综合征,另外一个可能的  相似文献   
97.
The present study investigated the effects of intramuscularly administered beta-carotene on reproductive parameters in female pigs. A total of 216 multiparous sows were observed from weaning of their litters until the next farrowing. On the day of weaning, the animals were allocated to two groups. Sows of the treatment group were injected with 70 mg beta-carotene both at the day of weaning and after the last insemination, sows of the control group were left untreated. For all sows, intramuscular injection of beta-carotene resulted in a significant increase of the total number of piglets born per litter by 1.2 (p < 0.05). When sows were divided by parity, beta-carotene treatment in second parity sows increased the total number of piglets per litter (beta-carotene 13.7 +/- 1.2, control 11.2 +/- 3.7, p < 0.01) and the number of piglets born alive (beta-carotene 12.0 +/- 2.7, control 10.0 +/- 3.4, p < 0.05). No such effect was seen in sows of third or higher parity. No other reproductive parameters were affected by beta-carotene supplementation. Tolerability and safety of the administered preparation were good. No side effects related to the medication were observed. The effect of beta-carotene on reproduction is thus affected by parity of the sows. This effect seems to be exerted mainly during early pregnancy and is most likely beta-carotene-specific and independent from its role as a vitamin A precursor.  相似文献   
98.
A 6-year-old intact female Labrador Retriever had diabetes mellitus, which had been difficult to control with insulin. The dog also had a solid ductal mammary carcinoma with very rapid growth, which was temporally related to onset of hypoglycemia. Eight months after initial diagnosis of diabetes, the dog had a hypoglycemic crisis. Insulin administration was stopped and serum glucose concentration returned to normal. Three months after discontinuing insulin, another hypoglycemic crisis occurred. During subsequent months, serum glucose concentrations remained at life-threatening levels (1.64-2.12 mmol/L, reference interval 4.44-6.66 mmol/L) simultaneously with an increase in the size of the mammary tumor, which reached a diameter of about 16 cm. At the time of surgery for removal of the tumor serum glucose concentration was 2.20 mmol/L and was then monitored every 3 hours after excision of the tumor. The glucose concentration continued to rise and reached 9.99 mmol/L 12 hours after the removal of the mammary tumor. Immunohistochemical staining demonstrated expression of insulin growth factor-2 by tumor cells, which apparently had caused the hypoglycemia during tumor growth even in a diabetic dog. Hyperglycemia associated with diabetes was pronounced after excision of the tumor and had been masked by the paraneoplastic effect of the tumor.  相似文献   
99.
Great interest is currently centred on the biologic activities of pycnogenol a standardized plant extract obtained from the bark of the French maritime pine Pinus pinaster (formerly known as Pinus maritima), Aiton, subspecies Atlantica des Villar (Pycnogenol®, Horphag Research Ltd., UK, Geneve, Switzerland), which grows in the coastal southwest France. The quality of this extract is specified in the United States Pharmacopeia (USP 28). Between 65% and 75% of Pycnogenol are procyanidins comprising of catechin and epicatechin subunits with varying chain lengths. Other constituents are polyphenolic monomers, phenolic or cinnamic acids and their glycosides. As many studies indicate, pycnogenol components are highly bioavailable. Uniquely, pycnogenol displays greater biologic effects as a mixture than its purified components do individually indicating that the components interact synergistically. Pycnogenol is now utilized throughout the world as a nutritional supplement and as a phytochemical remedy for various diseases ranging from chronic inflammation to circulatory dysfunction, including several impaired psycho-physiological functions. Owing to the basic chemical structure of its components, the most obvious feature of pycnogenol is its strong antioxidant activity. In fact, phenolic acids, polyphenols, and in particular flavonoids, are composed of one (or more) aromatic rings bearing one or more hydroxyl groups and are therefore potentially able to quench free radicals by forming resonance-stabilized phenoxyl radicals.  相似文献   
100.

Background, aim, and scope

An innovative stabilization/solidification (S/S) process using high-performance additivated concrete technology was developed for remediating soil contaminated by metals from abandoned industrial sites. In order to verify the effectiveness of this new ex situ S/S procedure, an area highly contaminated by metallic pollutants (As, Cd, Hg, and Pb), due to the uncontrolled discharge of waste generated from artistic glass production on the island of Murano (Venice, Italy), was selected as a case study. The technique transforms the contaminated soil into an aggregate material suitable for reuse as on-site backfill. This paper reports the main results of the demonstration project performed in collaboration with the local environmental protection agency (ARPAV).

Materials and methods

An ex situ treatment for brownfield remediation, based on the transformation of contaminated soil into very dense, low porous, and mechanically resistant granular material, was set up and tested. Specific additives (water reducers and superplasticizers) to improve the stabilized material properties were developed and patented. A demonstration plant assembled on the study area to treat 6 m3 h–1was then tested. After excavation, the contaminated soil was screened to remove coarse material. The fraction Ø?>?4 mm (coarse fraction), mainly composed of glass, brick, concrete, and stone debris, was directly reused on site after passing through a washing treatment section. The highly polluted fraction Ø?≤?4 mm (fine fraction) was treated in the S/S treatment division of the plant (European patent WO/2006/097272). The fine fraction was mixed with Portland cement and additives defined on the basis of the high performance concrete technique. the mixture was then granulated in a rolling-plate system. After 28 days curing in an onsite storage area to allow for cement hydration, the stabilized material was monitored before its in situ relocation. The chemical, mechanical, and ecotoxicological reliability and performance of the treatment was checked. Metal leachability was verified according to four leaching test methods: Italian Environmental Ministry Decree (1998), EN 12457 (2002) tout court, amended only with MgSO4 and, lastly, with artificial sea water. The mechanical properties were measured according to BS (1990) and AASHTO (1999) to obtain the Aggregate Crushing Value and California Bearing Ratio, in that order. Moreover, leachate samples prepared with artificial seawater were assessed via the Crassostrea gigas embryotoxicity test and Vibrio fischeri bioluminescence inhibition test to discriminate the presence of potential ecotoxicological effects for the brackish and saltwater biota.

Results

Outcomes from all leachate samples highlighted the effectiveness of the remediation treatment, fully complying with the Italian legislation for non-hazardous material reuse under a physicochemical viewpoint. The stabilized granular material demonstrated high mechanical strength, low porosity, and leachability. Moreover, ecotoxicological surveys indicated the presence of low toxicity levels in leachate samples according to both toxicity tests.

Discussion

Remediated soil samples revealed a significant decrease in leachability of heavy metals as a consequence of the application of additivated cement that enhanced granular material properties, resulting in improved compactness due to the reduction in water content. The toxicity data confirmed this state-of-the-art technique, indicating that leachates could be deemed as minor acutely toxic.

Conclusions

The proposed S/S treatment proved to be able to remediate soil contaminated by heavy metals through trapping pollutants in pellet materials presenting adequate physicochemical, mechanical, and ecotoxicological properties in order to prevent leachability phenomena, their reclamation, and reuse being made easier by its granular form.

Recommendation and perspectives

This project foresees long-term monitoring activity over several years (until 2014) to consider treatment durability.  相似文献   
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