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121.
Members of Veronica subg. Pseudolysimachium are widely known and cultivated for their large and dense ornamental inflorescences. Their success as cultivated plants stems in part to the cross‐compatibility of members of the subgenus and in part to their wide ecological amplitude ranging from species growing in wetlands to those of semi‐deserts. Due to large morphological variation and the presence of intermediate forms growing in sympatry of their putative parents, hybridization between the species is believed to be frequent. The Russian Altai is a center of diversity for the subgenus and many hybrid taxa have been described from there based on morphology. Here, we test these hybrid hypotheses using dominant SRAP markers. The method relies on primers anchored in open reading frames and amplifying intronic regions, which are scored as fragment length polymorphisms. Using seven primer pairs, we analyzed 63 loci without missing data. Our data support a close relationship of V. × grisea, V. × schmakovii and V. taigischensis with V. longifolia while the influence from the other suggested parents V. incana, V. porphyriana and V. pinnata was weak (at most). Similarly, V. × sessiliflora shows strong genetic similarity with V. porphyriana but only slight influence from V. pinnata. Overall, the methodology worked reliably and provided a large number of variable polymorphisms. The lack of support for the hybrid hypotheses may be due to the relatively low number of loci analysed and/or possible backcrossing with one of the parents. 相似文献
122.
E. VENDRAMIN M. T. DETTORI J. GIOVINAZZI S. MICALI R. QUARTA I. VERDE 《Molecular ecology resources》2007,7(2):307-310
Twenty‐one expressed sequence tag–simple sequence repeat (EST–SSR) markers were developed in peach from a mesocarp cDNA library. Eighteen of them gave successful amplification in 22 peach genotypes and produced one to three alleles each with an average of 1.8 alleles per locus. The average value of expected and observed heterozygosities was 0.24 and 0.20, respectively. All the primers gave successful amplification in other six Prunus species (almond, apricot, sweet cherry, Japanese plum, European plum and Prunus ferganensis). 相似文献
123.
Immuno-gold localization of IAA in leaf cells of Prunus persica at different stages of development 总被引:1,自引:0,他引:1
Subcellular localization of indole-3-acetic acid (IAA) in leaf cells of peach ( Prunus persica [L.] Batsch 'Hakuho') was investigated using imuno-gold electron microscopy. The distribution pattern of the gold particles, which detected IAA, changed as cells matured. The most prominent feature was the accumulation of the gold label in the chloroplasts and mitochondria of the parenchyma cells of opened leaves. Throughout the development, the cytosol, nuclei, and cell wall were labelled, although the level was low and no significant changes occurred. The density of colloidal gold at each stage of leaf development was well correlated with the analytical data obtained by high-performance liquid chromatography (HPLC). 相似文献
124.
On the relationship between leaf anatomy and CO2 diffusion through the mesophyll of hypostomatous leaves 总被引:11,自引:8,他引:3
J. P. SYVERTSEN J. LLOYD C. McCONCHIE P. E. KRIEDEMANN G. D. FARQUHAR 《Plant, cell & environment》1995,18(2):149-157
Internal conductances to CO2 transfer from the stomatal cavity to sites of carboxylation (gi) in hypostomatous sun-and shade-grown leaves of citrus, peach and Macadamia trees (Lloyd et al. 1992) were related to anatomical characteristics of mesophyll tissues. There was a consistent relationship between absorptance of photosynthetically active radiation and chlorophyll concentration (mmol m?2) for all leaves, including sclerophyllous Macadamia, whose transmittance was high despite its relatively thick leaves. In thin peach leaves, which had high gi, the chloro-plast volume and mesophyll surface area exposed to intercellular air spaces (ias) per unit leaf area were similar to those in the thicker leaves of the evergreen species. Peach leaves, however, had the lowest leaf dry weight per area (D/a), the lowest tissue density (Td) and the highest chloro-plast surface area (Sc) exposed to ias. There were negative correlations between gi and leaf thickness or D/a, but positive correlations between gi and Sc or Sc/Td. We developed a one-dimensional diffusion model which partitioned gi into a gaseous diffusion conductance through the ias (gias) plus a liquid-phase conductance through mesophyll cell walls (gcw). The model accounted for a significant amount of variation (r2=0.80) in measured gi by incorporating both components. The gias component was related to the one-dimensional path-length for diffusion across the mesophyll and so was greater in thinner peach leaves than in leaves of evergreen species. The gcw component was related to tissue density and to the degree of chloroplast exposure to the ias. Thus the negative correlations between gi and leaf thickness or D/a related to gias whereas positive correlations between gi and Sc or Sc/Td, related to gcw. The gcw was consistently lower than gias, and thus represented a greater constraint on CO2 diffusion in the mesophylls of these hypostomatous species. 相似文献
125.
Avni Öztürk 《Plant Systematics and Evolution》1978,130(3-4):293-298
Veronica allahuekberensis
A. Öztürk, spec. nova, probably endemic to the Allahuekber mountain in N.E. Anatolia, belongs toV. orientalis group of sectionVeronica and resemblesV. cuneifolia
D. Don subsp.cuneifolia, endemic to S.W. Anatolia. 相似文献
126.
127.
Ethylene biosynthesis in peach fruitlet abscission 总被引:5,自引:0,他引:5
128.
Søren Rosendal Jensen Charlotte Held Gotfredsen Renée J. Grayer 《Biochemical Systematics and Ecology》2008
In a chemosystematic investigation of three Southern hemisphere species of Veronica, namely the Australian Veronica derwentiana Andrews and Veronica perfoliata R.Br. (formerly Derwentia species), and the New Zealand Veronica catarractae G. Forster (formerly a species of Parahebe), the water-soluble constituents were isolated and identified by spectroscopic methods. Apart from other iridoid glucosides common to the genus, three unusual substituted benzoyl esters of aucubin (derwentiosides A–C) were obtained from V. derwentiana and a chlorinated iridoid glycoside (catarractoside) from V. catarractae in addition to other iridoids common to the genus. The chemical profile of V. perfoliata is similar to that of Northern hemisphere species of Veronica because of the presence of characteristic 6-O-catalpol esters. The profile of V. derwentiana is unique, since 6-O-esters of aucubin rather than of catalpol dominate, however, the acyl groups are the same as those present in catalpol esters found in some other Veronica sections. V. catarractae also contains one of the catalpol esters characteristic of Veronica, but in addition three 6-O-rhamnopyranosyl substituted iridoid glycosides, one of which is 6-O-rhamnopyranosylcatalpol. Esters of the latter compound are previously only known from the more derived species in recent phylogenetic trees of sect. Hebe to which V. catarractae now also belongs, but as a more basal member. 相似文献
129.