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A. G. WHITEHEAD D. J. TITE JANET E. FRASER EILEEN M. FRENCH 《The Annals of applied biology》1973,73(2):203-210
Applied to potato ridge soil in spring, before potatoes were planted, small amounts of aldicarb (10-3 kg/ha or less) controlled potato cyst-nematodes (Heterodera rostochiensis Woll.) better than large amounts of dazomet (110–466 kg/ha) or D-D (102–439 kg/ha). Applied in spring 1968 and 1969 to heavily infested sandy clay soil 466 kg dazomet/ha allowed Majestic potatoes to grow and yield well in both years without increasing the number of nematodes in the soil after harvest, but in peaty loam dazomet was toxic to potato plants and, when applied in autumn, killed fewer nematodes. D-D in potato ridges in spring controlled nematodes less well than dazomet or aldicarb, but 896 kg D-D/ha injected in sandy clay soil in autumn increased potato yield the following year without increasing the number of nematodes after harvest. 相似文献
63.
A Comparison of Seed and Seedling Phytochrome in Avena sativa L. using Monoclonal Antibodies 总被引:1,自引:0,他引:1
Hilton, J.R. and Thomas, B. 1985. A comparison of seed and seedlingphytochrome in Avena saliva L.using monoclonal antibodies.J.exp. Bot. 36: 19371946.The kinetics of phytochrome accumulationduring imbibition and germination of seeds of Avena saliva L.cv. Saladin has been determined in vivo by spectrophotometryand in extracts by using EnzymeLinked Immunosorbent Assay(EL1SA). In vivo measurements show two phases of phytochromeincrease. The first occurs during the initial 2 h of imbibitionand is associated with the hydration of the seed proteins; thesecond larger increase begins after 16 h, due probably to denovo synthesis. An ELISA using monoclonal antibodies purifiedfrom dark grown Avena seedlings detected only the second increasein phytochrome content. Mixing experiments indicate that theinability to detect phytochrome by ELISA during the first 16h is not due to the presence of inhibitors in the extracts.It is concluded that preexistent seed phytochrome isantigenically dissimilar to seedling phytochrome. These twopools of phytochrome are stable and unstable respectively withregard to Pfr destruction. Key words: Immunology, phytochrome, seed 相似文献
64.
A. G. WHITEHEAD D. J. TITE P. H. FINCH JANET E. FRASER EILEEN M. FRENCH 《The Annals of applied biology》1979,92(1):73-79
In peaty loam soils, aldicarb or oxamyl mixed with the top 15 cm of the soil in spring before sugar beet seeds were sown, minimised invasion of the roots by larvae of the beet cyst-nematode, Heterodera schachtii, so preventing injury to the seedlings, and greatly increased sugar yields in heavily infested soil. Small amounts of both compounds were often as effective as larger amounts. Nematode increase on sugar beet roots was slow. Aldicarb or oxamyl lessened nematode increase in four years out of five. Fumigating predetermined row positions with dichloropropene mixtures (D-D, Telone) or incorporating aldicarb or methomyl shallowly in soil, later occupied by the roots of sugar beet seedlings, did not control the nematode, although sugar yields were sometimes increased. 相似文献
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The biases towards eusociality, female workers and maternal care in haplodiploid versus diploid insects may result from the relatively low probabilities that rare mutant, partially dominant alleles promoting these behaviours will be lost by genetic drift in haplodiploid populations (Reeve, 1993). A generalization of this 'protected invasion' theory also predicts that parental and alloparental care will tend to be associated with the homogametic sex in diploid populations if the Y chromosome of the heterogametic sex is absent or largely inert. Sex differences in (allo)parental care (i.e. either parental or alloparental care) should increase with increased asymmetry between the sexes in the fraction of behaviour-influencing loci occurring on their characteristic sex chromosomes. The theory explains the strong predisposition towards female (allo)parental care in mammals, a contrasting tendency towards male (allo)parental care in birds, the propensity for joint male and female (allo)parental care in termites, and biases towards female cooperation in social spiders. The theory also explains the apparent rarity or absence of alloparental care in marsupials, an intriguing consequence of preferential paternal X-chromosome inactivation in this taxon. Thus protected invasion theory possibly provides new insights into the relationship between social structure and the genetic system. The theory does not compete with ecological or kin-selective hypotheses for the advantages of (allo)parental care; indeed, such advantages must exist for protected-invasion biases to operate. 相似文献
67.
JANET L. FINN 《American anthropologist》2007,109(2):408-409
Welfare Reform in Persistent Rural Poverty: Dreams, Disenchantments, and Diversity . Kathleen Pickering, Mark H. Harvey, Gene F. Summers, and David Mushinski. University Park: Pennsylvania State University Press, 2006. 243 pp. 相似文献
68.
The root apices of Allium sativum have been examined by continuous-and pulse-labelling with tritiated thymidine and by colchicinetreatment to measure the time parameters of the mitotic cyclein various parts of the meristem. There is a quiescent centre of 3050 cells whose averagerate of mitosis is low because the G1 period is extended toabout 140 h compared with about 4 h in the othe regions of themeristem. The stele just above the quiescent centre and at 200microns above it and the cap initials just below the quiescentcentre are very similar in their mitotic cycles, the total lengthsof which are about 30 h of which nearly half is taken up byDNA synthesis. Allium thus differs from Zea in having root capinitials whose mitotic cycle is not telescoped by the eliminationof the G1 phase. These facts are discussed in relation to theradiosensitivity of the meristem. 相似文献
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