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71.
Chrysin is a bioflavonoid compound found in passion flower, chamomile, propolis and honey at high levels. Post‐thawed sperm quality and fertility of Chrysin‐fed roosters were assessed in this study. Twenty 40‐week‐old male broiler breeders were randomly divided into four groups and fed basal diet supplemented with different levels of Chrysin including 0 (Ch‐0), 25 (Ch‐25), 50 (Ch‐50) or 75 (Ch‐75) mg/day for 12 consecutive weeks. Semen samples were weekly collected from 6th to 9th week of experiment to evaluate some sperm quality parameters including total and progressive motility, plasma membrane integrity and functionality (in fresh and post‐thawed samples) and mitochondrial activity (only in post‐thawed samples). Also, collected semen samples from 10th, 11th and 12th week of experiment were frozen and then artificially inseminated to test fertility rate. According to the results, an improvement in both fresh and post‐thawed sperm quality including total [fresh: 88.00 ± 0.58 and 87.25 ± 0.67 (p < .01); post‐thawed: 51.07 ± 2.05 and 52.72 ± 1.96 (p < .01)] and progressive motility [fresh: 76.00 ± 0.58 and 78.25 ± 0.65 (p < .01); post‐thawed: 40.61 ± 2.01 and 39.88 ± 2.01 (p < .01)], plasma membrane integrity [fresh: 91.60 ± 0.58 and 89.85 ± 0.59 (p < .01); post‐thawed: 56.99 ± 1.86 and 54.39 ± 1.86 (p < .01)] and functionality [fresh: 75.40 ± 0.42 and 77.90 ± 0.96 (p < .01); post‐thawed: 45.69 ± 1.71 and 46.35 ± 1.71 (p < .01)] was noted for both Ch‐50 and Ch‐75, respectively, groups compared to control group. Despite no significant change in mitochondrial activity, fertility rate of post‐thawed spermatozoa was significantly improved in all Chrysin‐fed groups compared to Ch‐0 group. In conclusion, oral Chrysin administration to roosters could ameliorate cryopreservation‐induced impairment of sperm quality and fertility rate.  相似文献   
72.
Cannabis sativa is a plant that produces an oil with psychoactive and stress reduction effects and thus illegal in many nations. Lately, the beneficial properties of the plant extract are becoming better understood and perceptions are changing. As the aquaculture industry matures from a primitive extensive pond system to an industrialized intensive system, fish stress and disease incidence are increasing, with negative economic results. A nutritional ingredient that could reduce stress and disease incidence in aquacultured fish would thus be opportune. In the present work we investigated whether ether extracted cannabis oil would relieve stress, improve growth and feed conversion, and/or improve haematological indicators of disease resistance. Three diets were made to contain either soy oil, industrial hemp oil or cannabis oil and offered to tilapia for 8 weeks. At termination, survival, growth, feed conversion and blood parameters were assessed. Fish were returned to their tanks, offered the same feeds as during the experiment and respiration assessed. Cannabis extract was found to increase metabolism and thus increase feed conversion. On the other hand, cannabis had no effect on blood cell counts, total plasma protein, haematocrit or lysozyme activity. Results thus suggest that cannabis does not improve immune response of tilapia or body composition but does reduce growth rate by increasing metabolic rate.  相似文献   
73.
The release of alachlor from controlled-release formulations (CRFs) based on alginate-montmorillonite matrices into aqueous polyethylene glycol (PEG) solutions of different concentrations and into a soil at different moisture contents was studied. In distilled water and in PEG-containing solutions displaying -0.1 MPa potential and up, the beads imbibe water and swell. The ensuing increase in weight is about 5%, and the increase in the bead's diameter is about 10%. At water potentials of -0.5 MPa and lower, loss of weight and shrinkage of the beads were observed. The changes in weight and diameter of the alginate-clay beads incubated in a Hamra loamy sand soil at 26.5% moisture content (w/w; -0.18 MPa) were similar to those observed in PEG solutions of >-0.5 MPa moisture potential. The weight and diameter losses observed in the drier soils (12.0 and 7.1% water content; -0.49 and -1.11 MPa) were similar to those in the more concentrated PEG solutions. A decrease in the rate of release of the active ingredient from the beads into soil was observed as the water potential decreased (drier soils). The release of the active ingredient from the investigated CRFs displayed a linear relationship to the square root of time, suggesting a diffusion-controlled-release rate. Data extracted from this relationship enabled the formulation of a mathematical model that correlates rate of release to water content.  相似文献   
74.
The research was performed to investigate the effect of zeolite and zinc on the qualitative characteristics of canola cultivars at different moisture regimes. Factorial split plot experiment was performed on the basis of the randomized complete blocks design with three replications in Karaj, Iran. The treatments were: 1) irrigation (I): complete (normal irrigation) (I1), and restricted irrigation (I2) applied at the pod formation stage, 2) zeolite (Z): 0 (Z1), and 15 t ha?1 (Z2), and 3) Zn: zinc sulfate concentrations of 0%, 0.1%, and 0.2% (Zn1, Zn2, and Zn3) on Opera, Licord, and RGS003 cultivars. The highest rate of all studied traits was obtained by applying Z2Zn2 (15 ton ha?1 zeolite and 0.1% zinc sulfate) in both irrigation regimes. Opera cultivar in normal irrigation and RGS003 cultivar in stress conditions had the highest yield and yield components, oil yield, and oil content.  相似文献   
75.
We examined the effects of malathion, an organophosphorus (OP) insecticide, on glucagon, C-peptide, and insulin content or secretion from isolated rat Langerhans islets in vitro. Islets were isolated from the pancreas of rats by standard collagenase digestion, separation by centrifugation, and hand-picking technique. Then islets were cultured in medium and supplemented with various concentrations of malathion (25, 125, and 625 μg/ml) for 1, 3, and 5 h. In vitro exposure to malathion increased insulin and C-peptide contents at doses of 25, 125, and 625 μg/ml following 5 h incubation as compared to control. All doses of malathion increased glucagon content after 3 and 5 h as compared to control. Increase of the glucagon content at all doses in the fifth hour was higher than that of third hour. Malathion also decreased 2.8 and 16.7 mM glucose-stimulated insulin secretion at all doses after 30 min as compared to control.It is concluded that malathion reduce insulin exocytose in a short time (first hour) but after a long time (e.g., 5 h), the content of insulin is increased by compensating mechanisms such as resynthesize of insulin or aggregation of insulin. The present in vitro study for the first time proposes the involvement of subcellular non-cholinergic mechanisms in malathion-induced changes in Langerhans islets insulin and glucagon.  相似文献   
76.
Hyperglycemia is observed with exposure to organophosphorus (OP) pesticides. The aim of this study was to investigate the effects of malathion on secretion of insulin from rat pancreatic islets in vitro and in vivo. Malathion was administered through food for 4 weeks at concentrations of 100, 200, and 400 ppm. For in vivo experiment, at the end of treatment, blood sample was obtained and plasma was separated. For in vitro experiment, the treated rats were anesthetized and underwent a laparatomy. The common bile duct was cannulated and the pancreas distended by injecting of cold collagenase V using peristaltic infusion pump. Islets were then hand picked under a stereomicroscope and cultured in the presence of various doses of glucose and KCl. Malathion at doses of 200 and 400 ppm increased plasma glucose and insulin concentrations and lowered activity of erythrocyte acetylcholinesterase. The isolated islets from pretreated animals with malathion 200 and 400 ppm showed lower glucose-stimulated insulin secretion while no change was observed in the presence of KCl. Light microscopic examination revealed that malathion causes patchy degenerative changes in pancreatic islets. Combination of in vivo and in vitro findings suggests that malathion induces a kind of insulin resistance that cannot overwhelm hyperglycemia. This action of malathion is mediated through disruption of islets mitochondrial function.  相似文献   
77.
The impact of the density of Sunn Pest egg parasitoids, Trissolcus grandis Thomson (Hymenoptera: Scelionidae), at three levels of Sunn Pest, Eurygaster integriceps Puton (Hemiptera: Scutelleridae), infestation was assessed on bread wheat variety Cham 6 in screened cages in the field for percentage of egg parasitism and grain quality. Percent parasitism ranged from 60.1 to 83.9%. No statistically significant differences were detected at parasitoid densities of 1, 2, or 3 insects per square meter at Sunn Pest densities of 2 or 4 insects per square meter. The quality of grain collected from all Sunn Pest infested cages without egg parasitoids was unacceptable for baking purposes and was significantly lower than grain from both non-infested plots and plots where either two or three egg parasitoids were present. The abundance of egg parasitoids in Al Hassakeh province in Syria was also determined. Egg parasitism was observed 1 week after the initiation of Sunn Pest oviposition and ranged between 22 and 59% in non-insecticide treated fields, while no parasitoids were recovered from insecticide treated areas within the same region. The impact of feeding by Sunn Pest on different wheat stages indicated that only feeding prior to the spike stage does not affect the bread-making quality of the grain.  相似文献   
78.
79.
Microplot experiments were carried out during the autumn and winter of 1995 to determine the effects of soil moisture and levels of organic matter on the carpogenic germination of Sclerotinia sclerotiorum and subsequent infection of Phaseolus vulgaris . Soil moisture treatments were established by irrigation to field capacity: (a) when soil had dried to − 25 KPa, (b) when soil had dried to − 54 KPa, and (c) eight days after the soil had dried to − 54 KPa. Three levels of organic matter were established by mixing compost and yellow-red latosol in the following proportions (by volume): (a) 0% compost and 100% soil, (b) 50% compost and 50% soil, and (c) 100% compost and 0% soil. More apothecia and diseased plants were observed in the plots with higher moisture levels. Drier treatments resulted in a reduction in number (in the winter experiment) or elimination (in the autumn experiment) of apothecia. Other experiments were designed to examine the effect of grass mulching and organic matter levels on the carpogenic germination of S. sclerotiorum . In one experiment, grass mulching was compared with no mulching, and in another, the effects of different depths of mulch on the soil surface (0, 1.5, 3, 6 and 9 cm) were examined. Fewer apothecia were formed in mulched soil and the effect was most pronounced with 6 and 9 cm of mulch. The highest level of mulch (9 cm) impaired the vigour and yield of bean plants. In these experiments, carpogenic germination was increased by high soil organic matter content. Control of soil moisture and grass mulching may reduce the production of apothecia of S. sclerotiorum even in soils rich in organic matter.  相似文献   
80.
This study examines how institutional varieties at the subnational (state) level influence firm-level innovation in an emerging economy—India. Knowledge of how institutional varieties influence firm-level innovation is derived principally from country-level studies involving multiple developed countries. Research on emerging economies is sparse and tends to follow country-level approaches involving multiple countries. Research involving a single emerging economy where there are substantial institutional varieties between regions is thin. The institutional varieties of some emerging countries are so striking that they can be viewed as several countries within a country, for example, India, China. This study contributes to the innovation literature on the role of institutional varieties on firm-level innovation by focusing on a different level of analysis—a single, emerging economy with substantial institutional varieties across the different states of India. Innovation in emerging economies is a topic of increasing academic interest. A multilevel study involving regional- and firm-level factors is employed. Firm-level data are from the World Bank Enterprise Survey and regional-level data are from statistical agencies in India. The results confirm that institutional varieties have major impacts on firm-level innovation. The research, policy, and managerial implications are discussed.  相似文献   
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