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61.
Salicylic acid (SA) is an inducer of systemic acquired resistance (SAR) and could be a potential candidate in the control of plant virus diseases. In this study we assayed under controlled conditions the potential effect of three doses of exogenous SA treatment on tomato plants infected with Potato virus X (PVX) and measured their effects on: different physiological parameters (gas exchange, stable isotopes, chlorophyll content), the activation of secondary metabolism, viral accumulation and induction of the expression of pathogenesis-related proteins (PRs) such as ß-1, 3-glucanase (PR2) and chitinase (PR3). SA treatment increased the expression of PR2, the activity of phenylalanine ammonia lyase (PAL) and the concentration of antioxidant compounds at 7 days post-treatment. Earlier expression of PR3 compared to PR2 was observed. SA treatment delayed the detection of PVX by ELISA in uninoculated leaves of mechanically infected tomato plants. Although the effect of PVX infection on physiological parameters was weak, moderate SA treatments showed enhanced photosynthesis, particularly for infected plants. The results obtained confirm that SA promotes major changes in the induction of resistance in tomato plants and suggest that treatment with exogenous SA could be considered to reduce the infections caused by PVX.  相似文献   
62.
Reasons for performing study: Treadmill locomotion is frequently used for training of sport horses, for diagnostic purposes and for research. Identification of the possible biomechanical differences and similarities between the back movement during treadmill (T) and over ground (O) locomotion is essential for the correct interpretation of research results. Objectives: To compare the kinematics of the thoracolumbar vertebral column in treadmill and over ground locomotion in healthy horses. Methods: Six sound Dutch Warmblood horses trotted on a T and O during 10 s at their own preferred velocity (mean ± s.d. 3.6 ± 0.3 m/s T and 3.6 ± 0.1 m/s O), which was the same in both conditions. Kinematics of the vertebral column was captured by infrared cameras using reflective skin markers attached over the spinous processes of selected vertebrae and other locations. Flexion‐extension and lateral bending range of motion (ROM), angular motion pattern (AMP) and intravertebral pattern symmetry (IVPS) of 5 vertebral angles (T6‐T10‐T13, T10‐T13‐T17, T13‐T17‐L1, T17‐L1‐L3 and L1‐L3‐l5) were calculated. Neck angle, linear and temporal stride parameters and protraction‐retraction angles of the limbs were also calculated. Results: The vertical ROM (flexion‐extension) was similar in both conditions, but the horizontal ROM (lateral bending) of the lumbar angles T17‐L1‐L3 and L1‐L3‐L5 was less during T locomotion (mean ± s.d. difference of 1.8 ± 0.6 and 1.7 ± 0.9°, respectively, P>0.05). During O locomotion, the symmetry pattern of the lumbar vertebral angles was diminished from 0.9 to 0.7 (1 = 100% symmetry) indicating increased irregularity of the movement (P>0.05). No differences were found in the basic linear and temporal stride parameters and neck angle. Potential relevance: Vertebral kinematics during treadmill locomotion is not identical to over ground locomotion, but the differences are minor. During treadmill locomotion lumbar motion is less, and caution should be therefore taken when interpreting lumbar kinematics.  相似文献   
63.
The aim of this work was to determine the influence of different processing procedures and preparations on the viability and infectivity of Trichinella spiralis ML. The muscles of limbs tongue and masseters of pigs experimentally infected were collected, splitted to pieces, and pooled. Five batches were used for the following processing procedures: (1) seasoning with “adobo”, commercially acquired chilli and several other spices, (2) “wet-curing” by immersion of meat pieces in 3% brine during 24 hours, (3) cold storage without any further processing or preparation, (4) freezing to -20°C and, (5) drying for 24 hours at 60°C. Samples were stored at 4°C for 15, 45, 60, 75, 90, 105 or 266 days after preparation. At the last-mentioned dates, ML were recovered and used to determine the reproductive capacity by infecting naïve mice. The state of meat conservation or spoilage respectively was tested by visual and tactile examination. In samples treated by freezing or drying no motile larvae were found after artificial digestion and, following inoculation of mice with larvae recovered from these groups, no ML were founded after 40 days of infection. After the artificial digestion of the cold stored samples, the ones seasoned with “adobo” and “wet-cured”, a number of motile ML were consistently obtained. Initial reproductive capacity index was as of 80±0.5, then rates decreased to 60 – 70 between days 15 and 105 PT and dropped to 40±6.7 at day 266 for seasoned, 33±2.7 for cold-stored and 33±2.5 for cured samples. The influence of storage time (p=0.000005; factorial ANOVA) but not for processing procedure (p=0.724; factorial ANOVA) were statistically significant. The sensorial examination of the meat samples showed severe changes caused by spoilage in odour, texture and colour from day 45 of storage. Data reported from this trial proves that curing or flavoring do not inactivate the Trichinella Mexican strain, although cold storage for more than three months led to a partial decrease of the reproductive capacity. Freezing and drying seemed to be effective measures to eliminate the ML infectivity.  相似文献   
64.
Common beans are rich in phenolic compounds, which can provide health benefits to the consumer. The objective of this work was to study the relationship among antimutagenicity, antioxidant and enzymatic activities of methanolic extract and trolox by principal components multivariate analysis. Antimutagenicity of phenolic compounds present in methanolic extract from the seed coat of common beans (P. vulgaris, Flor de Mayo Bajío cultivar) and trolox against AFB1 mutagenicity were evaluated in the Salmonella typhimurium microsuspension assay. Antioxidant capacity of methanolic extract and trolox were evaluated using β-carotene and 1,1-diphenyl-2-picryhydrazyl (DPPH) in vitro model assays. Cythrome P450 activity was measured by fluorometric assay. For phenolic extract, trolox and phenolic extract + trolox, the inhibition on AFB1 mutagenicity in tester strain TA100 was 47, 59 and 69%, respectively. While in TA98 was 39, 48 and 68%. The inhibition of phenolic compounds, trolox and phenolic compounds + trolox on cytochrome P450 (CYP450) activity was 48, 59 and 88%, respectively. Correlation analysis showed that phenolic extract and trolox have high antimutagenic and antioxidant activity and also inhibited enzymatic activity. The results suggest that the primary mechanism of action of phenolic compounds in beans against AFB1 mutagenicity may be extra-cellular in the microsuspension assay.  相似文献   
65.
Fish Physiology and Biochemistry - Inflammation is one of the main causes of loss of homeostasis at both the systemic and molecular levels. The aim of this study was to investigate in silico the...  相似文献   
66.
Since 1980, over 20,000 Irish landowners have afforested land, for the first time, as part of an afforestation programme subsidised by the Government and the EU. A survey of 99 private forest owners was conducted to determine their knowledge of broad aspects of forest management. Key questions were scored so as to test whether respondents had passed or failed a forestry knowledge test. Over two-thirds of private forest owners passed the test. Success in this test was shown to be related to whether respondents had (a) attended extension field days; (b) been active in forest operations in the early stages of the forest cycle and (c) been members of farming and/or forestry groups. Younger respondents (i.e., ≤50 years) were more likely to pass the knowledge test than older respondents.  相似文献   
67.
The objective of this article is to present a new way to incorporate the sectoral dimension within the components of regional growth provided by the traditional shift–share analysis. The new methodology elaborates the way that the dynamics of a specific sector in a region are influenced by the performance of other sectors, the latter decomposed between national, structural, and differential effects. To illustrate this extension of the shift–share method, an application is provided using data for the Spanish region of Extremadura for the period 1990–2004. The results highlight how these new components can shed new insights into the analysis of sectoral and regional economic growth processes.  相似文献   
68.
The purpose of this study was to evaluate the hypolipidemic effect of a methanolic extract from Opuntia joconostle seeds fed to mice in a hypercholesterolemic diet. Acute toxicity of the methanolic extract was investigated by an established method. Phenolic composition and antioxidant activity were determined by high-performance liquid chromatography and DPPH, respectively. The total phenolic content of Opuntia joconostle seeds was 47.85?±?1.29 mg gallic acid equivalents/g dry weight. The main phenolic compounds were identified as quercetin, rutin, and cafeic acid. Percent inhibition of DPPH+ was 49.76?±?0.49 %. The oral LD50 for the methanolic extract from the Opuntia joconostle seeds was >5,000 mg/kg BW. Mice fed a hypercholesterolemic diet for six days exhibited significantly (P?≤?0.001) higher plasma lipid levels than mice fed a normal diet. Remarkably, supplementation with methanolic extract from Opuntia joconostle at doses of 1, 2, and 5 g/kg body weight significantly (P?≤?0.001) prevented the increase in total cholesterol, low-density lipoprotein cholesterol, triglycerides level, and atherogenic index. Similar concentrations of the HDL cholesterol were observed in both treated and control groups. A significant dose-dependent reduction in lipid levels was noted for treated groups compared to the hypercholesterolemic group. We attribute this result to the seeds’ phenolic composition. This methanolic extract has potential to be included in short-term hypercholesterolemia treatment regimens as it exhibits hypolipidemic activity with no apparent toxic manifestations.  相似文献   
69.
Two experiments were conducted on the effects of bronopol in the artificial incubation of crayfish eggs (Pacifastacus leniusculus) with the aim to search an alternative to formaldehyde. In the first experiment, 50, 250, 500 and 1000 ppm bronopol and 3000 ppm formaldehyde (control) in periodical administrations were tested on a density of 6.6 eggs cm?2. After 44 days of incubation, the highest survival was obtained with 1000 ppm bronopol (81.9% to stage 2 juvenile, with no significant difference from formaldehyde), whereas lower bronopol concentrations resulted in significantly lower survival. In the second experiment, 1000, 3000 and 5000 ppm bronopol and 3000 ppm formaldehyde (control) administered for 15 min every second day were tested on eggs at a density of 20 eggs cm?2. After 78 days of incubation, bronopol at 3000 ppm allowed for a stage 2 juvenile survival rate of 65.0% (with no significant difference from formaldehyde), whereas significantly lower survival was obtained with 1000 ppm or 5000 ppm. This study shows that bronopol may constitute an alternative to formaldehyde in the artificial incubation of crayfish eggs. A concentration of 3000 ppm administered for 15 min every second day may be adequate even on long incubations at high densities (at least 20 eggs cm?2, one complete layer).  相似文献   
70.
We assessed by numerical modeling the coastal fish larval dispersion along the southern coast of Mallorca (Balearic Islands, NW Mediterranean) with the objective of determining the factors that contribute to successful recruitment. We assumed that fish larvae dispersal is mainly regulated by physical transport. Currents are mainly wind driven in this area; therefore, changes in wind forcing have a first‐order impact on larval transport. The synoptic wind patterns were systematically analyzed based on self‐organizing map analysis. The wind fields were clustered using a neural network pattern recognition approach into two modes, producing opposite along‐shelf flow. The seasonal changes between spring and summer in the dominance of either mode modulate the along‐shelf circulation, producing flow shifts under some circumstances. This variability in the wind regime was consistent throughout the 10 years analyzed (2000–2009). Using the Princeton Ocean Model (POM) and a particle‐tracking algorithm, we analyzed the effect of wind‐forced currents in the connectivity among near‐shore habitats. We show that, at the spatial scale considered, the coastal morphology and stochastic wind forcing favor local recruitment (mean of 30% self‐recruitment). Maximum transport distances of 20–30 km were typically associated with particles left to drift for 21 days. The implications for the performance of the four marine protected areas near SW Mallorca Island are discussed. Our results suggest that, although wind episodes determine the fate of short‐time spawning events, on a seasonal basis, regular larval supply to coastal zones is ensured by wind stochasticity.  相似文献   
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