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991.
ObjectiveTo evaluate the physiological effect and response to noxious stimulation at five concentrations of MS-222 in koi (Cyprinus carpio).Study designProspective experimental study.AnimalsTwenty-one healthy adult unknown sex koi fish weighing mean 450 ± SD 120 g.MethodsEach fish was exposed to five different concentrations of MS-222 (50, 70, 110, 150 and 190 mg L?1) in a random sequence during the same anaesthetic event. For each concentration of MS-222, vital functions such as heart rate (HR) (via Doppler) and opercular rate (OpR) were recorded after a standardized induction period. Response to two noxious stimuli in the form of haemostat clamp pressure applied on the tail and the lip was evaluated, and blood was drawn to measure biochemical and blood gas values.ResultsDecrease in response to noxious stimulation with an increase of MS-222 concentration both for the lip (p = 0.0027) and the tail (p < 0.0001) stimulus was observed. Biochemical values were unaffected by the concentration of MS-222 with the exception of lactate concentration which was weakly correlated with the duration of anaesthesia (r = 0.31, p < 0.001) and the number of times the fish was clamped or bled prior to sampling (r = 0.23, p < 0.001). Opercular rate decreased with the increase in anaesthetic concentration, and HR was not affected.Conclusions and clinical relevanceOur results indicated a decrease in response to stimulus and a decrease in OpR that were associated with increased concentrations of MS-222. This may assist in establishing anaesthetic protocols using MS-222 in fish and supports the use of supramaximal pressure stimuli to teleost fish under variable MS-222 concentrations as a model for future studies.  相似文献   
992.
993.
994.
ObjectiveTo investigate the contribution of K+ channels on peripheral antinociception induced by ketamine.Study designProspective experimental study.Animals110 male Wistar rats weighing 160–200 g.MethodsThe paw pressure required to elicit limb flexion was designated as the nociceptive threshold. Hyperalgesia was induced by intraplantar injection of prostaglandin E2. All drugs were administered locally into the right hind paw of rats. Ketamine was administered into the right hind paw 2 hours and 55 minutes after local injection of PGE2. Tetraethylammonium was administered 30 minutes prior to ketamine and the other K+ channel blockers, glibenclamide, dequalinium and paxilline, were administered 5 minutes prior to ketamine.ResultsProstaglandin E2 (2 μg per paw) induced hyperalgesia. Ketamine (10, 20, 40 and 80 μg per paw) elicited a local peripheral antinociceptive effect that was antagonized by a specific blocker of ATP‐sensitive K+ channels, glibenclamide (20, 40 and 80 μg per paw). In another experiment, the non‐selective voltage‐dependent K+ channel blocker tetraethylammonium (30 μg per paw) and small and large conductance blockers of Ca2+‐activated K+ channels, dequalinium (50 μg per paw) and paxilline (20 μg per paw), were ineffective at blocking the effect of a local ketamine injection.Conclusions and clinical relevanceAnalysis of these results provides evidence that ketamine, may in part, induce peripheral antinociceptive effects by ATP‐sensitive K+ channel pathway activation.  相似文献   
995.
Studies of displays in the Charadrii (= waders or shorebirds) show that the same posture in different species, even quite closely related, may have a different function in a given context. As a corollary to this, two species even in the same genus may have quite different display postures to convey the same message. The problem is thus twofold: (a) to interpret the function of the display in the bird's world and (b) to trace the evolution of the display within a single well-defined suborder of birds such as the Charadrii. Threat displays are especially informative in such studies, but courtship, distraction and other displays are also useful. The value of display postures in the systematics of the waders is discussed.  相似文献   
996.
《African Zoology》2013,48(2):302-303
Sociality confers many benefits to gregarious animals, but group-living does not come without associated costs. Social living can cause anxiety, which if prolonged can lead to stress. We investigate correlates of anxiety and stress among wild adult male olive baboons (Papio hamadryas anubis) in Gashaka-Gumti National Park, Nigeria, and present the first examination of these correlates for male baboons living in forested environments. We used rates of self-directed behaviours (SDB) to quantify anxiety, and faecal glucocorticoid (FGC) concentrations to quantify physiological stress. We first examined the relationship between SDB rates and FGC concentrations, and then examined each measure in relation to a range of variables previously linked to anxiety or stress. We found that SDB rates and FGC concentrations were not correlated with each other, nor were they related to any measure of grooming or receiving aggression. SDB rates were negatively correlated with time spent with an adult female as nearest neighbour, but were unrelated to time with another adult male as closest conspecific. FGC concentrations were unrelated to time with adult nearest neighbours of either sex. Our results add to the growing body of literature examining the psychological and physiological costs of social living among wild primates.  相似文献   
997.
《African Zoology》2013,48(3):249-257
Understanding fish movement patterns and migrations is important for fisheries management as well as the identification and conservation of critical habitats. Data collected by the Oceanographic Research Institute's Cooperative Fish Tagging Project (ORI-CFTP) were used to describe the large-scale movement patterns of Lichia amia along the South African coastline. A total of 10 762 L. amia were tagged between 1984 and 2012, of which 744 (7%) were recaptured. Most tagging effort, mainly on juvenile and subadult individuals, took place along the south-eastern (i.e. Eastern Cape) and south-western (i.e. Western Cape) regions of the country during summer. Conversely, more L. amia were tagged and recaptured (mostly adults) during winter and spring (July to November) along the north-east coast (i.e. KwaZulu-Natal). Movements (dispersal distance in kilometres) by juveniles were restricted and largely confined to estuaries within the south-eastern and south-western regions of the country. There was a significant effect of fish size on distance moved (ANOVA: p<0.001), with evidence of a distinct seasonal (winter) longshore migration by adults to KwaZulu-Natal. The consequences of juvenile residency in estuarine habitats and high recapture rate of adults during a directed, seasonal spawning migration are discussed in light of improving current fisheries management.  相似文献   
998.
Summary

Revisiting the history of Oregon politics, especially environmental policy, shows that populist tradition and innovative government are tied together. Political innovation through massive reform led to the Oregon System, a governmental approach that allows a good deal of direct, or participatory, democracy. The degree of direct democracy in Oregon, or at least the threat of voters bypassing the legislature, led to a series of environmental laws passed in the 1970s. Along with similar federal laws, these set a regulatory baseline from which to build a watershed protection strategy. Key to this Watershed Health Program is the role of community-based watershed councils, which provide a good example of local, inclusive, participatory democracy. Utilizing watershed councils as the key component of a state watershed restoration strategy within the context of a regulatory baseline is an example of a hybrid centralized/decentralized approach to environmental policy. This hybrid approach is a political innovation that serves as an incremental response to competing environmental and anti-government populism. This approach will be severely tested by the 1997 Oregon Plan for Salmon and Healthy Watersheds, a state conservation plan designed to head off a listing of salmonid species under the Endangered Species Act. If this approach is successful, community-based ecosystem management groups and states that wish to copy Oregon's example will have new ideas to foster maintenance and restoration of ecosystems through state-administered conservation plans.  相似文献   
999.
Ten Nubian goats were given oral doses of the fresh fruits and leaves of Cassia senna at 1, 5, and 10 g / kg /day. Eight goats died within 30 days and two others were slaughtered in a moribund condition on days 18 and 29. The clinical signs of diarrhoea, inappetence, loss of condition, and dyspnoea were well correlated with the pathological findings. There was an increase in G.O.T., ammonia, urea, and total cholesterol and a decrease in total protein in the serum of Cassia‐poisoned goats. Blood sugar level was reduced and the increase in the values of Hb, PCV, and RBC was due to haemoconcentration.  相似文献   
1000.
Summary

The effect of 60 minutes’ intravenous infusions, before morning feeding, of ammonium acetate (18.6 micromole/min/kg of body weight) and ammonium acetate with propranolol (11 μg/min/kg of body weight) on the ruminal motility of sheep was examined. Ammonia has an adrenaline‐like action therefore propranolol, a beta‐receptor blocking agent, was administered in order to eliminate the possible effect of adrenaline on ruminal motility. The contractions of the dorsal sack of the rumen were registered by means of the balloon method, with the gauge inserted through the rumen fistula. The infusion of ammonium acetate caused an increase of the ammonia concentration in the blood to 0.6 mmolel/at the end of 60 minutes’ infusion. Already during the first 5 minutes of the intravenous infusion of ammonium acetate there was a decreased frequency of ruminal contractions, which was observed throughout the infusion. After the infusion there was a radical decrease of the concentration of ammonia in the blood, and at the same time an increase in the frequency of rumen contraction was observed.

Blocking of the beta‐adrenergic receptors by propranolol did not eliminate the inhibiting action of ammonium ion on rumen motility. The infusion of the ammonium acetate caused an increase of adrenaline and glucose concentration. This response was eliminated by propranolol in the case of adrenaline but not glucose. It is assumed that the action of ammonium ion on the rumen motility is derived primarily by the central nervous system.  相似文献   
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