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91.
In this article, I examine the variable representation of Saami (Lapp) prehistory in several Nordic museums. The analysis is situated at the intersection of (1) the examination of the ideology of archaeological practice, (2) the discourse about creation of indigenous identity, and (3) the visual culture of museum exhibitions. I describe and analyze displays about archaeology and prehistory from seven museums in Sweden, Finland, and Norway. The presentation of Saami prehistory differs significantly between majority community museums and those run by Saami communities. These presentations reflect ideologies implicated in building indigenous, nationalist, and pannational identities as well as in establishing legitimacy of Saami claims to land and heritage. Representations of the past are inevitably political because they are about linking people, place, and legitimacy. Ambiguities in these uses of prehistory are discussed, as is the globalizing role of the European Union.  相似文献   
92.
CLADISTIC ANALYSIS OF THE OCTOPODS BASED ON ANATOMICAL CHARACTERS   总被引:2,自引:0,他引:2  
Parsimony analysis of 29 finned and finless octopod taxa considered66 anatomical and morphological characters to discover synapomorphiesthat unite monophyletic groups. The resultant cladogram (177equally parsimonious trees at 191 steps, CI 0.429) resolvedall relationships except those among the 16 exemplars of theOctopodidae included and those among Tremoctopus, Ocythoe andArgonauta. Bootstrap values of over 90% support the monophylyof the finned and finless octopods, relationships among thefinned octopods, the bolitaenids and the monophyly of Haliphron,Tremoctopus, Ocythoe and Argonauta; bootstrap values for othernodes range from 57 to 79%. Among finned octopods, specimensrepresenting Grimpoteuthis are basal, as Voss (1988a) suggested.Specimens of Opisthoteuthis represent a distinct lineage, andare sister taxon, in this analysis, of Cirroteuthis (althoughspecimens of Stauroteuthis could not be included). New definitionsof the genera Opisthoteuthis and Grimpoteuthis are providedto reflect their separate evolutionary histories rather thantheir overt morphological similarity. Among finless octopods,bolitaenids are basal. The monophyletic Octopodidae is the sistertaxon to the clade containing the sister taxa Vitreledonellaand Amphitretus, and Haliphron, Tremoctopus, Ocythoe and Argonauta.The Ctenoglossa and Heteroglossa, families grouped by sharedradular dentition, are diphyletic and paraphyletic, respectively.The cladistic relationships demonstrate that both the Vitrele-donellidaeand Idioctopodidae are junior synonyms of the Amphitretidae;despite conspicuous morphological differences separating thesetaxa, they share a recent evolutionary history.  相似文献   
93.
1. From a single founder virgin female of each species, nine and seven successive parthenogenetic generations of Cloeon dipterum and Cloeon simile, respectively, were reared: all offspring were female. Eggs were removed from final instar nymphs, subimagos and virgin imagos of each generation and their development assessed. The life cycles of 487 individual C. dipterum and 315 C. simile were recorded, together with details of growth rate, egg production and adult size of these and other representatives of each generation. In order to distinguish between the effects of parthenogenesis and the effects of culture conditions, fertilized eggs of both species were reared under the same laboratory conditions. 2. Fewer unfertilized than fertilized eggs hatched. There was no consistent trend in the percentage hatch in successive parthenogenetic generations. In both species the time taken for parthenogenetic individuals to complete a generation varied considerably, and no relationship was found between generation length and the number of parthenogenetic generations that had passed, the developmental stage of the donor, or the time taken for the eggs to hatch. After 50 weeks there was, in both species, an overlap of up to six generations. The number of eggs produced by both species was significantly greater in the first parthenogenetic generation than in later generations but the numbers for later generations lie within the recorded range of egg number in imagos captured in the field. 3. To find if parthenogenetic individuals occur in the field, the sex ratios of last instar nymphs and subimagos of C. simile were measured in samples collected over 13 successive years from a set of small isolated pools. There was a female bias both in winter and at the start of the emergence season. It is possible that, when mature nymphs and emerging subimagos are damaged by predators, the eggs which are released from them survive and develop. 4. Mature, egg-containing nymphs of both species were present in the field throughout the year, although their numbers were small at the beginning of winter. 5. Oviposition by imagos captured from mating swarms and by virgin imagos, of both species, was recorded for the first time, showing that C. dipterum is not always ovoviviparous. It is suggested that early instar nymphs occurring in mid-winter come not only from unfertilized eggs released from injured nymphs and subimagos, but also from fertilized eggs laid in autumn.  相似文献   
94.
The importance of kastom to national identity in Vanuatu has been recognized. In this paper I identify plaiting technology in general and basketry in particular — which once served to distinguish ethnic groups in Vanuatu — as emerging symbols of ni-Vanuatu unity. I argue that unlike these kastom traditions often discussed in the literature, plaiting and basketry need not be reinvented. Plaiting is a customary practice which has rich contemporaneous expressions. Plaited products may be fully elaborated in local detail and yet, as shared productions of a technology with common features, can simultaneously represent ni-Vanuatu identity.  相似文献   
95.
As little as 0.8 kg aldicarb ha-1 applied to bands of soil 15 cm wide × 15 cm deep, in which sugar beet seeds were sown, increased beet yields as much as did 2.6 or 5.0 kg ha-1 rotary cultivated into the top 15 cm of soil lightly or moderately infested with beet cyst-nematode, Heterodera schachtii. In a very heavily infested soil, 1.7 kg ha-1 applied to the bands of soil increased beet yields as much as 2.6 kg ha-1 rotavated into the top 15 cm of the soil; yields were further increased by 5.0 and 9.9 kg ha-1 rotavated in but not by 3.5 kg ha-1 in the bands of soil. Soil populations of the nematode increased little or not at all whether the soil was treated with aldicarb or not. The band treatment was achieved by a vertical band- reciprocating harrow technique, which is described. The advantages of this new technique for the control of beet cyst-nematode and other soil pests of widely spaced row crops are safer application of less pesticide, thereby minimising cost of treatment and any risk to the environment, faster seedbed preparation and adequate control of pest population increase on the susceptible crop, especially if coupled with biological control.  相似文献   
96.
Dicotyledonous plants were reliably inoculated with stem nematodes by placing drops of 1.3% carboxymethylcellulose containing the surface sterilised worms between the cotyledons or in the leaf axils of recently emerged seedlings raised in pots of cool, moist soil. Inoculating onion leaves, bean stems and potato tubers or potato leaves gave variable results and inoculating onion, tulip and narcissus bulbs and lucerne and red clover stems was usually unsuccessful. An attempt to characterise 67 stem nematode populations by the reactions of a number of different plants failed for lack of useful differential hosts. Lucerne was, however, resistant to all but lucerne populations. Multiplication of stem nematode populations varied greatly between cultivars of lucerne or red clover. Some cultivars were resistant to some populations of lucerne or red clover stem nematodes and susceptible to others. These differences could not be ascribed to differences in viability of the nematodes or to differences in success of the inoculations. They indicate the presence of different pathotypes or biotypes in different populations of a so-called ‘host race’ and indicate the need for new resistant cultivars to be tested against a range of populations before they are released for general use. Amongst lucerne cultivars tested, Vertus was resistant to some lucerne stem nematode populations and susceptible to others. The supposedly resistant lucerne cultivars Euver and Lifeuil were as susceptible as was Europe. Amongst red clover cultivars tested, Redhead, Kühn, Changins and Mt Calme were susceptible, Britta, Lucrum and Temara were the least resistant, Renova, Rittinova and Quin were intermediate and susceptible to one or more of the populations tested but Norseman and especially Sabtoron were very resistant.  相似文献   
97.
. Ornithine decarboxylase and trypanothione reductase are the key enzymes in polyamine and trypanothione metabolism in kinetoplastids. Using a heterologous Trypanosoma brucei brucei probe for ornithine decarboxylase and a mixed synthetic probe of 29 oligonucleotides for trypanothione reductase, we have detected the putative genes for these enzymes by Southern blot hybridization using genomic DNA of Leishmania braziliensis guyanensis MHOM/SR/80/CUMC I. The trypanothione reductase probe was constructed both from the conserved codon usage of the redox active site for other flavin oxidoreductases over a wide evolutionary scale, and the preferred codon usage for other genes in species of Leishmania .  相似文献   
98.
Stem canker (Rhizoctonia solani) of maincrop potatoes.   总被引:1,自引:0,他引:1  
In two years, potato plants were sampled at 1- or 2- weekly intervals from plots planted with seed tubers bearing sclerotia of Rhizoctonia solani (black scurf) and with seed without sclerotia either infested or not with cultures of R. solani at planting. Sprouted King Edward seed was used in 1981 and sprouted and non-sprouted King Edward and Pentland Crown seed in 1982. In both years 60–80% of shoots from seed with sclerotia and 90% of shoots from seed inoculated at planting were affected with stem canker. Most disease developed before shoots emerged although it gradually increased later when new shoots arising both from seed tubers or as branches on shoots with damaged apices (pruned shoots) became infected before they emerged. Sprouting seed tubers bearing sclerotia decreased the disease on both cultivars but with soil-applied inoculum the disease was more severe on plants from sprouted than non-sprouted seed. Some stolons were infected by R. solani soon after they developed and incidence of infection later increased. Thirty to 50% of stolons were infected on plants from infected seed tubers and 60% on plants with soil-applied inoculum. With both cultivars and sources of inoculum about 70% of the infected stolons had their apices killed (pruned).  相似文献   
99.
(1) Parallel evolution from separate marine ancestors has given rise to two groups of genera of terrestrial nemerteans, representative of at least two different family stocks. They have colonized land by the direct route, moving up the shore on widely separated oceanic islands. The relationships between the known terrestrial and semi-terrestrial nemerteans, comprising seven genera and 15 species, are defined and their geographic distribution is discussed.
(2) In fresh water, three heteronemertean and nine hoplonemertean species are known. The hoplonemerteans arise from two different families representing two different evolutionary routes to fresh water, one by way of estuaries and the other via land. The distribution of freshwater nemerteans and the characters common to all species are discussed.
(3) Very little is known about the comparative physiology of land and freshwater nemerteans. However, information about the physiology of marine forms is combined with morphological differences from them found in terrestrial and freshwater species to suggest profitable lines of future research.
(4) Water relations pose a major problem for both terrestrial and freshwater nemerteans. The role of the cerebral organs, the blood and the excretory system in the osmotic physiology of some littoral nemerteans is beginning to be understood. These systems in land and freshwater forms have clearly distinctive features which need to be thoroughly investigated.
(5) Suggestions are given for valuable lines of investigation of the mucous glands, digestive physiology and general behaviour of terrestrial and freshwater nemerteans.  相似文献   
100.
Light, fluorescence and electron microscopy were employed to follow the development of the endodermis in cluster roots and lateral roots of Grevillea robusta A. Cunn. ex R. Br. Endodermal cells had three different origins: rootlet endodermis arose from the rootlet meristem; endodermis covering the primordium shortly after initiation came from division of parental endodermis; cells at the junction between parent and rootlet endodermis developed from re-differentiated rootlet cortical cells. In the cluster root, the Casparian band formed in three ways, and was not initially present opposite the two sets of single xylem elements in the rootlet stele. A new clearing technique was developed that allowed visualization of xylem, suberized endodermis, Casparian band formation and phenolic compounds. In lateral roots, endodermal differentiation was asynchronous, but was related to position relative to protoxylem poles. However, the observed delay began before these poles had differentiated. At the tip of mature rootlets, which are determinate, the endodermis terminates in a 'dome' of cells, with the initial cell differentiating as an endodermal cell. Results are discussed in terms of determinate development in roots and the spatial and temporal contexts within which this development takes place.  相似文献   
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