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11.
Brzozowski Lauren J. Weber Donald C. Wallingford Anna K. Mazourek Michael Agrawal Anurag A. 《Journal of pest science》2022,95(1):327-338
Journal of Pest Science - Co-occurring herbivorous pests may have shared or divergent responses to plant- and insect- derived cues, creating challenges for effective pest management in... 相似文献
12.
Treatment of wheat straw using tannase and white-rot fungus to improve feed utilization by ruminants
Background
Current research to enrich cattle feed has primarily focused on treatment using white rot fungi, while there are scarce reports using the enzyme tannase, which is discussed only in reviews or in the form of a hypothesis. In this context, the aim of the present study was to evaluate the effect of tannase on wheat straw (WS) and also the effect of lyophilized tannase at concentrations of 0.1%, 0.2%, and 0.3% (w/w) on WS followed by fermentation with Ganoderma sp. for 10 d and compared in relation to biochemical parameters, crude protein (CP) content, and nutritional value by calculating the C/N ratio in order to improve the nutritional value of cattle feed.Results
Penicillium charlesii, a tannase-producing microorganism, produced 61.4 IU/mL of tannase in 54 h when 2% (w/v) tannic acid (TA) was initially used as a substrate in medium containing (% w/v) sucrose (1.0), NaNO3 (1.0), and MgSO4 (0.08 pH, 5.0) in a 300-L fermentor (working volume 220 L), and concomitantly fed with 1.0% (w/v) TA after 24 h. The yield of partially purified and lyophilized tannase was 5.8 IU/mg. The tannin-free myco-straw at 0.1% (w/w) tannase showed 37.8% (w/w) lignin degradation with only a 20.4% (w/w) decrease in cellulose content and the in vitro feed digestibility was 32.2%. An increase in CP content (up to 1.28-fold) along with a lower C/N ratio of 25.0%, as compared to myco-straw, was obtained.Conclusions
The use of tannin-free myco-straw has potential to improve the nutritional content of cattle feed. This biological treatment process was safe, eco-friendly, easy to perform, and was less expensive as compared to other treatment methods. 相似文献13.
A. S. Khehra B. S. Dhillon N. S. Nalhi S. S. Pal V. K. Saxena V. V. Malhotra 《Euphytica》1986,35(3):817-822
Summary Reciprocal recurrent selection was carried out with two populations of maize (Zea mays L.) having good combining ability. We selected for higher grain yield, early maturity, shorter plant height and lodging resistance. Two cycles were completed in two years (four seasons), by resorting to late planting of S1 lines for recombination in the main season in which top-cross families were assessed. Top-crosses and selfings were made in the off-season. The original and improved versions of the populations and their crosses were evaluated in multilocation trials. The superiority of the population hybrid was 10.3% for grain yield, 5.5% for plant height and 1.8 days to silk. The improved hybrid had delayed leaf senescence and better resistance to lodging and post-flowering stalk rots. Among the yield components, only ear girth showed improvement. Syn 2 of the improved population cross showed a yield reduction of 6.2% in comparison to Syn 1. Intrapopulation gains were not significant except for lodging resistance in one population. 相似文献
14.
Cajanus reticulatus var. grandifolius, endemic to Australia and a wild relative of the cultivated species, C. cajan, was successfully crossed with the latter as the female parent. The major wild species characters such as persistent stipules,
long pod hairs, pod shattering, brown seeds with grey speckles, and presence of seed strophiole were dominant in the hybrid.
For growth and branching habit, and leaflet, flower, pod, and seed size, the hybrid was intermediate between the parents.
The meiotic cells of the hybrid were found to have quadrivalents, trivalents, univalents,and showed reduced chromosome pairing
as revealed by the increased number of rod bivalents per cell at metaphase-I, and stickiness and precocious movement of chromosomes
to poles in the second division. In comparison to the parents, the hybrid had fewer pods and seeds. However,these anomalies
in the interspecific hybrid are not significant enough to preclude the gene transfer from C. reticulatus to the cultivated species through a sexual route.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
15.
Tetrahymena pyriformis, a common freshwater ciliate concentrated the four common HCH (Hexachlorocyclohexane) isomers viz., α, β, δ, and γ to varied extent. Bioconcentration factor [as expressed by the ratio of cellular insecticide in ng mg?1 (dry weight) to supernatant in ng μL?1 ranged from 342 to 2260 for α-HCH, 37 to 831 for β-HCH, 326 to 2806 for δ-HCH and from 106 to 1214 ppm for γ-HCH. 相似文献
16.
The Influence of Glutathione on Physiological Effects of Lead and its Accumulation in Moss Sphagnum Squarrosum 总被引:1,自引:0,他引:1
An attempt has been made to study the physiological andbiochemical responses and to evaluate the bioaccumulationpotential of moss Sphagnum to environmental lead. Supply of0.1 to 100 mM lead acetate caused a loss in chlorophyll andnitrogen content of moss and in nitrate reductase activity in themoss, although the peroxidase activity was increased. Partialrecovery in the above parameters was recorded upon simultaneoustreatment with glutathione. Results also indicate that treatmentwith glutathione increased the bioaccumulation potential bylowering the lead toxicity, which could be the result of inductionof metal binding capabilities of cells as the heavy metal alsoinduced the synthesis of phytochelatins. The moss accumulated asignificant amounts of Pb under both experimental and fieldconditions. The heavy metal accumulated by moss was positivelycorrelated to the soil metal content. The experiments demonstratethat Sphagnum is able to accumulate and tolerate higheramounts of Pb and therefore, it can be used as a bioindicator andphytoremediator of lead contaminated environment. 相似文献
17.
18.
The charnockite geotherm 总被引:1,自引:0,他引:1
Saxena SK 《Science (New York, N.Y.)》1977,198(4317):614-617
Charnockite, a hypersthene-bearing granite, and other associated rocks of the charnockite series have a global distribution. These rocks, according to evidence from mineral-chemical and experimental phase equilibrium relations, formed or recrystallized at temperatures between 800 degrees and 900 degrees C and at relatively shallow depths of 6 to 12 kilometers. This evidence indicates the existence of geothermal gradients of 70 degrees to 100 degrees C per kilometer probably at various times, the latest being around 1300 x 10(6) years ago. 相似文献
19.
A gonadotropin similar to human chorionic gonadotropin or luteinizing hormone has been demonstrated in rabbit blastocyst prior to implantation. The gonadotropin has been detected by a radioreceptor assay for human chorionic gonadotropin with the use of the plasma membranes of bovine corpora lutea obtained during the first trimester of pregnancy. The concentrations of the human chorionic gonadotropin or luteinizing hormone per milliliter of blastocyst fluid were tenfold higher than those in the blood of pregnant rabbits on days 5 and 6 after mating. 相似文献
20.
Dubrovinsky LS Dubrovinskaia NA Saxena SK Annersten H Hålenius E Harryson H Tutti F Rekhi S Le Bihan T 《Science (New York, N.Y.)》2000,289(5478):430-432
We have heated ferropericlases (Mg(0.60)Fe(0.40))O and (Mg(0.50)Fe(0.50))O to temperatures of 1000 kelvin at pressures of 86 gigapascals, simulating the stability of the solid solution at physical conditions relevant to Earth's lower mantle. The in situ x-ray study of the externally heated samples in a Mao-Bell-type diamond anvil cell shows that ferropericlase may dissociate into magnesium-rich and iron-rich oxide components. The result is important because the decomposition of ferropericlase into lighter and heavier phases will cause dynamic effects that could lead to mantle heterogeneity. 相似文献