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91.
The estrogenic isoflavones of soybeans and their glycosides are products of the shikimate pathway, the target pathway of glyphosate. This study tested the hypothesis that nonphytotoxic levels of glyphosate and other herbicides known to affect phenolic compound biosynthesis might influence levels of these nutraceutical compounds in glyphosate-resistant soybeans. The effects of glyphosate and other herbicides were determined on estrogenic isoflavones and shikimate in glyphosate-resistant soybeans from identical experiments conducted on different cultivars in Mississippi and Missouri. Four commonly used herbicide treatments were compared to a hand-weeded control. The herbicide treatments were (1) glyphosate at 1260 g/ha at 3 weeks after planting (WAP), followed by glyphosate at 840 g/ha at 6 WAP; (2) sulfentrazone at 168 g/ha plus chlorimuron at 34 g/ha applied preemergence (PRE), followed by glyphosate at 1260 g/ha at 6 WAP; (3) sulfentrazone at 168 g/ha plus chlorimuron at 34 g/ha applied PRE, followed by glyphosate at 1260 g/ha at full bloom; and (4) sulfentrazone at 168 g/ha plus chlorimuron at 34 g/ha applied PRE, followed by acifluorfen at 280 g/ha plus bentazon at 560 g/ha plus clethodim at 140 g/ha at 6 WAP. Soybeans were harvested at maturity, and seeds were analyzed for daidzein, daidzin, genistein, genistin, glycitin, glycitein, shikimate, glyphosate, and the glyphosate degradation product, aminomethylphosphonic acid (AMPA). There were no remarkable effects of any treatment on the contents of any of the biosynthetic compounds in soybean seed from either test site, indicating that early and later season applications of glyphosate have no effects on phytoestrogen levels in glyphosate-resistant soybeans. Glyphosate and AMPA residues were higher in seeds from treatment 3 than from the other two treatments in which glyphosate was used earlier. Intermediate levels were found in treatments 1 and 2. Low levels of glyphosate and AMPA were found in treatment 4 and a hand-weeded control, apparently due to herbicide drift.  相似文献   
92.
Faecal contamination on lettuce growing in the open as indicated by the presence of Escherichia coli I was demonstrated for up to 21 days after irrigation with sewage effluent, although the level of contamination usually decreased after 3–7 days. Recovery of other coliform bacteria gave parallel results ; counts of these organisms and of other bacteria also indicated the persistence of more general pollution.  相似文献   
93.
Aminomethylphosphonic acid (AMPA) is the most frequently detected metabolite of glyphosate in plants. The objective of this study was to determine if there is any correlation of metabolism of glyphosate to AMPA in different plant species and their natural level of resistance to glyphosate. Greenhouse studies were conducted to determine the glyphosate I 50 values (rate required to cause a 50% reduction in plant growth) and to quantify AMPA and shikimate concentrations in selected leguminous and nonleguminous species treated with glyphosate at respective I 50 rates. Coffee senna [ Cassia occidentalis (L.) Link] was the most sensitive ( I 50 = 75 g/ha) and hemp sesbania [ Sesbania herbacea (P.Mill.) McVaugh] was the most resistant ( I 50 = 456 g/ha) to glyphosate. Hemp sesbania was 6-fold and Illinois bundleflower [ Desmanthus illinoensis (Michx.) MacM. ex B.L.Robins. & Fern.] was 4-fold more resistant to glyphosate than coffee senna. Glyphosate was present in all plant species, and its concentration ranged from 0.308 to 38.7 microg/g of tissue. AMPA was present in all leguminous species studied except hemp sesbania. AMPA concentration ranged from 0.119 to 4.77 microg/g of tissue. Shikimate was present in all plant species treated with glyphosate, and levels ranged from 0.053 to 16.5 mg/g of tissue. Non-glyphosate-resistant (non-GR) soybean accumulated much higher shikimate than glyphosate-resistant (GR) soybean. Although some leguminous species were found to be more resistant to glyphosate than others, and there was considerable variation between species in the glyphosate to AMPA levels found, metabolism of glyphosate to AMPA did not appear to be a common factor in explaining natural resistance levels.  相似文献   
94.
Research suggests that polyphenolic compounds contained in fruits and vegetables that are rich in color may have potent antioxidant and anti-inflammatory activities. The present studies determined if stilbene (e.g., resveratrol) compounds would be efficacious in reversing the deleterious effects of aging in 19 month old Fischer 344 rats. Experiment I utilized resveratrol and six resveratrol analogues and examined their efficacies in preventing dopamine-induced decrements in calcium clearance following oxotremorine-induced depolarization in COS-7 cells transfected with M1 muscarinic receptors (MAChR) that we have shown previously to be sensitive to oxidative stressors. Experiment II utilized the most efficacious analogue (pterostilbene) from experiment I and fed aged rats a diet with a low (0.004%) or a high (0.016%) concentration of pterostilbene. Results indicated that pterostilbene was effective in reversing cognitive behavioral deficits, as well as dopamine release, and working memory was correlated with pterostilbene levels in the hippocampus.  相似文献   
95.
Community economies in Monsoon Asia: Keywords and key reflections   总被引:1,自引:1,他引:0       下载免费PDF全文
A diversity of place‐based community economic practices that enact ethical interdependence has long enabled livelihoods in Monsoon Asia. Managed either democratically or coercively, these culturally inflected practices have survived the rise of a cash economy, albeit in modified form, sometimes being co‐opted to state projects. In the modern development imaginary, these practices have been positioned as ‘traditional’, ‘rural’ and largely superseded. But if we read against the grain of modernisation, a largely hidden geography of community economic practices emerges. This paper introduces the project of documenting keywords of place‐based community economies in Monsoon Asia. It extends Raymond William’s cultural analysis of keywords into a non‐western context and situates this discursive approach within a material semiotic framing. The paper has been collaboratively written with co‐researchers across Southeast Asia and represents an experimental mode of scholarship that aims to advance a post‐development agenda.  相似文献   
96.
The efficacy of ultrasound-guided cholagogue-induced gallbladder emptying for differentiating obstructive from non-obstructive hepatobiliary diseases was studied in icteric dogs. In 7 healthy Beagle dogs, Lipofundin 20% infusion (2 ml/kg orally) evoked a vigorous gallbladder contraction of 44.2% (range: 35.3-57.6%) and proved to be a useful, well-tolerable meal for routine use. In 24 icteric dogs, gallbladder contraction was evoked by different cholagogues: the maximum reduction in gallbladder volume (%) for the three non-obstructive icteric dogs was 43.9% (range, 39.0-46.5%). The average gallbladder contraction of the 21 dogs with biliary obstruction was less than 5%. In conclusion, the stimulation of gallbladder contraction with orally applied magnesium sulphate (MgSO4) or Lipofundin can be well demonstrated by ultrasound in dogs. The examination of cholagogue-induced gallbladder emptying is a valuable technique in icteric patients to indicate surgical intervention.  相似文献   
97.
An 11 yr old spayed female Labrador retriever was diagnosed with a right adrenal tumor. At surgery, adhesions to the right kidney were dissected, allowing the right kidney to be preserved. The tumor showed extensive invasion into the suprarenal vena cava. It was felt that thrombus removal via venotomy could not be performed. Instead, the vena cava was ligated caudal to the liver and cranial to the right renal vein. The neoplastic gland was then excised en bloc together with the portion of the invaded caudal vena cava. Hind limb edema had developed preoperatively and increased transiently in the first days postoperatively. The animal was discharged 6 days postoperatively with no other clinical disorders, and hind limb edema resolved over time. Histopathology identified a pheochromocytoma. The dog died 49 mo later. A neoplastic thrombus of the vena cava may require venotomy to allow thrombus removal. Occasionally, removal of the thrombus by venotomy may prove impossible. In such a situation, en bloc removal of the concerned portion of the vena cava may be performed with a good long-term outcome provided that gradual occlusion of the vena cava by the thrombus has allowed time for collateral circulation to develop.  相似文献   
98.
The enteropathogenicity of avian reoviruses (ARVs), isolated from chickens affected with malabsorption syndrome (MAS) from The Netherlands and Germany was studied. In the first trial seven different ARVs isolated from MAS cases were inoculated in 1-day-old specific pathogenic free (SPF) white leghorns. The pathogenicity was compared with 2 ARVs isolated from cases of tenosynovitis, namely reference strain S1133 and a Dutch strain. Although a difference in the severity of the clinical disease was observed, all reoviruses could induce vacuolar degeneration and sloughing of the epithelium of the small intestine at day 2 post inoculation (PI) till day 7 PI. Two Dutch and one German ARV derived from MAS causing the most severe intestinal lesions at day 2 PI, were further studied in the second trial using SPF broilers. These reoviruses did not cause weight gain depression in the broilers although lesions in the small intestine were present from day 1 up to day 4 PI and were more severe than in the white leghorn chickens. In one of the inoculated groups apical denuded villi were already present at day 1 PI. At day 7 PI the small intestine of the infected broilers appeared to be normal. Reovirus antigen was detected in the cytoplasm of the enterocytes at the tip and middle section of the affected villi both in layers and in broilers. To study the role of intestinal CD4+ and CD8+ T-cells and macrophages/monocytes in the pathogenesis of ARV, the numbers of these cells of the jejunal villi of one infected and the control broiler groups were compared. CD4+ T-cells were detected in low numbers and only in the infected broiler group at day 14 PI. The numbers of CD8+ T-cells and macrophages/monocytes were significantly higher in the infected broiler group than in the control broiler group at day 7 and 14 PI and at day 7 PI respectively. Our study indicates that the reovirus alone cannot induce intestinal lesions as found in MAS chickens. Moreover, CD8+ T-cells may play a major role in the pathogenesis and or reovirus clearance in the small intestine.  相似文献   
99.
The absorption of ethanol from the rumen was studied in three British Milk sheep equipped with a rumen cannula. After removal of the rumen content and washing the forestomachs several times the reticulo-omasal orifice was closed and through the cannula 20 or 60 ml ethanol and 2 ml Cr-EDTA were infused in physiological saline. The entire fluid volume was 3000 ml. At the start of the experiment (0 min) and subsequently in the 5th, 15th, 30th, 45th, 60th and 75th minutes samples were taken from the fluid present in the forestomachs. During the 75-min experiment the amount of ethanol gradually decreased in the rumen. The rate of disappearance varied according to concentration. The graph depicting the change of ruminal ethanol concentration shows a curve typical of passive transport. The equation describing the disappearance of ethanol was y = -0.0474x2 + 5.6544x + 10.869 after the administration of 20 ml ethanol, and y = -0.1377x2 + 19.541x - 24.606 after the infusion of 60 ml ethanol. It was established that ethanol was absorbed through the rumen wall by a passive transport process.  相似文献   
100.
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