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41.
European Journal of Plant Pathology - Tea (Camellia sinensis) is a popular and extensively consumed beverage in Malaysia along with many other countries around the world. Grey blight is one of the...  相似文献   
42.
Use of an event scale MUSLE model for obtaining accurate long-term annual sediment yield estimates from micro-watersheds was evaluated. Such estimates are extremely important for designing appropriate soil/water conserving measures. For easy extraction and inputting of model input parameters, the proposed model was interfaced to an Arc-View/Spatial Analyst geographic information system. Application of this GIS interfaced MUSLE model on two gauged (pine and oak forest) hilly micro-watersheds viz., Salla Rautella (0.47 km2) and Naula (0.42 km2), in Almora district of Uttaranchal, India showed that it could estimate annual sediment yields with absolute mean relative errors ranging between 12-14%. Even long-term average sediment yields for Salla Rautella (observed: 9.58 tons and estimated: 10.92 tons) and Naula: (Observed: 23.89 tons and estimated: 26.61 tons) micro-watersheds could be quite realistically simulated by the proposed model.  相似文献   
43.
Marine bio-sourced chitosan nanoparticles (CSNP) are antimicrobial and immunomodulatory agents beneficial for fish medicine. Herein, dietary CSNP was investigated for the amelioration of the systemic inflammatory responses of an induced fish model. One hundred and forty-four rainbow trout were assigned to one pathogen-free and non-supplemented group (negative control), and three challenged groups: non-supplemented (positive control), CSNP-preventive, and CSNP-therapeutic. After a feeding experiment extended for 21 days, the organosomatic indices (OSI) and molecular aspects were assessed. After a challenge experiment extended for further 28 days, CSNP-therapeutic intervention was assessed on fish survival and systemic inflammatory responses on pathology, histo-morphology, and molecular aspects. With CSNP administration, OSI nonsignificantly decreased and the relative expression of targeted inflammatory-mediator genes was significantly increased. The CSNP-therapeutic fish showed an RPS of 80% as compared to the positive control group, and CSNP-therapeutic administration retained the highest gene expression augmentation up to 28 days after the challenge. Notably, the splenic reticulin fibers framework of the CSNP-therapeutic group retained the highest integrity among the groups during the infection. After recovery, reticulin fibers density in the CSNP-therapeutic samples was significantly higher than in the negative control group, which indicates high innate immunity. Thus, CSNP showed promising biotherapeutic features enhancing fish resistance against infections.  相似文献   
44.
Quercetin triglycoside from Capparis spinosa.   总被引:8,自引:0,他引:8  
In addition to rutin, quercetin 3-O-glucoside and quercetin 3-O-glucoside-7-O-rhamnoside, the methanolic extract of the aerial parts of Capparis spinosa yielded the new flavonoid quercetin 3-O-[6'"-alpha-L-rhamnosyl-6"-beta-D-glucosyl]-beta-D-glucoside (1).  相似文献   
45.
Field experiments have been carried out to evaluate the potency of the biological control agentBacillus thuringiensis (Dipel), the pyrethroid Fenvalerate and their combinations for the control of the lesser cotton leafwormSpodoptera exigua on soybeans in Qualubia governorate. Molasses was combined with all treatments to enhance their effectiveness. One spray application with either Dipel or Fenvalerate showed an obvious reduction in larval counts ofS. exigua, associated with a significant increase in the crop yield but in varying degrees, in correlation with the tested dose. Treatments with combinations of both biological and chemical insecticides at the lowest tested doses (62 g ofB. t. +50 ml of Fenvalerate/feddan) showed to be highly potential, and caused 2.8 fold increase in the crop yield. It may be recommended that a combination of both preparations may be used for the control ofS. exigua.  相似文献   
46.
Tests were conducted to evaluate the larvicidal effectiveness of three controlled-release plastic formulations of both chlorpyrifos and sumithion against mosquito larvae ofCulex pipiens. Excellent control with 90–100% larval mortality was achieved for 85, 77, 73, and 64, 54, 48 days posttreatment by using the non-expanded, expanded and foamed formulations of chlorpyrifos and sumithion, respectively. Apart from lethal action, larval treatments with the above formulations led to an increase in the mean number of basal follicles developed by mosquito females which survived from these treatments. The increase in this mean per female was in respect 23.4, 30.0, 18.7% in case of chlorpyrifos formulations, and 21.8, 17.2, 26.8% in case of sumithion formulations.  相似文献   
47.
New flavonoids from Avicennia marina   总被引:8,自引:0,他引:8  
In addition to luteolin 7-O-methylether, chrysoeriol 7-O-glucoside and isorhamnetin 3-O-rutinoside, the methanol extract of the aerial parts of Avicennia marina yielded two new flavonoids identified as luteolin 7-O-methylether 3'-O-beta-D-glucoside and its galactoside analogue 2.  相似文献   
48.
Field tests were conducted to determine the effectiveness of wheat-brain baits based onBacillus thuringiensis var.kurstaki HD-1 (dipel 2x) compared to the organophosphorous insecticide Hostathion against the greasy cutwormAgrotis ypsilon infestations on horse bean (Vicia fabae) cultivations. Significant larval reductions were observed in all treated plots after one application with a significant increase in the yield (1.45–1.60 folds) compared to the control plots. The yield was not obviously affected by varying the dose of dipel in the bait between 150–250 g/feddan. The addition of the adjuvant potassium carbonate to the dipel bait caused a significant larval reduction, 10 days after application and showed to be as efficient as baits based on Hostathion.  相似文献   
49.
This study aimed to determine the erythrocytic lipid peroxidation and haemoglobin oxidation as contributory factors causing anaemia in cattle (Friesian × Egyptian native breed) infected with Babesia bigemina. Blood was collected from 32 cows infected with B. bigemina along with 18 healthy cows as controls for determination of erythrocytic malondialdehyde (MDA), blood methaemoglobin (MetHb), plasma free haemoglobin (PHb), corpuscular osmotic fragility (COF), red blood cell count (RBC), total haemoglobin (Hb) and packed cell volume (PCV). Percentage of parasitaemia varied from 14% to 36%. MDA, MetHb, COF and PHb were significantly increased (P < 0.001) in infected cows versus controls. Parasitaemia was positively correlated (P < 0.001) with MDA, MetHb, COF and PHb. MDA was positively correlated (P < 0.001) with COF and PHb and negatively correlated (P < 0.001) with RBC, Hb and PCV. MetHb was negatively correlated (P < 0.001) with RBC, Hb and PCV and positively correlated (P < 0.001) with COF. In conclusion, B. bigemina infection in cattle is associated with a parasitic burden-dependent corpuscular oxidative damage as indicated by membrane lipid peroxidation and methaemoglobin formation, which are contributed to COF and intravascular haemolysis.  相似文献   
50.
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