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Christie A.M. Peebles Jacqueline V. Shanks Ka‐Yiu San 《Biotechnology and bioengineering》2009,103(6):1248-1254
The octadecanoid pathway is responsible for producing jasmonic acid an important signaling molecule in plants, which controls the production of a variety of secondary metabolites. Previously the exogenous addition of jasmonic acid to Catharanthus roseus hairy roots caused an increase in terpenoid indole alkaloid (TIA) accumulation. The role of the endogenous production of jasmonic acid by the octadecanoid pathway in the production of TIAs in C. roseus hairy roots is examined. Feeding of octadecanoid pathway inhibitors suggests that the octadecanoid pathway does not actively control TIA production under normal growth conditions or during the UV‐B stress response in C. roseus hairy roots. Biotechnol. Bioeng. 2009;103: 1248–1254. © 2009 Wiley Periodicals, Inc. 相似文献
505.
The breeding biology of the endemic Coquerel’s Coua (Coua coquereli), a non-parasitic cuckoo species for which few ecological data are available, was studied in the dry deciduous forest of
western Madagascar. Nestling C. coquereli remain in the nest for only a short time after hatching. At approximately 9 days old and still unable to fly, they were observed
to leave the nest and then remained on the ground where they were fed by both parents. This behaviour is probably a strategy
used to reduce nestling predation. 相似文献
506.
Richard R. Lawler Hal Caswell Alison F. Richard Joelisoa Ratsirarson Robert E. Dewar Marion Schwartz 《Oecologia》2009,161(3):491-504
In this study, we use deterministic and stochastic models to analyze the demography of Verreaux’s sifaka (Propithecus verreauxi verreauxi) in a fluctuating rainfall environment. The model is based on 16 years of data from Beza Mahafaly Special Reserve, southwest
Madagascar. The parameters in the stage-classified life cycle were estimated using mark-recapture methods. Statistical models
were evaluated using information-theoretic techniques and multi-model inference. The highest ranking model is time-invariant,
but the averaged model includes rainfall-dependence of survival and breeding. We used a time-series model of rainfall to construct
a stochastic demographic model. The time-invariant model and the stochastic model give a population growth rate of about 0.98.
Bootstrap confidence intervals on the growth rates, both deterministic and stochastic, include 1. Growth rates are most elastic
to changes in adult survival. Many demographic statistics show a nonlinear response to annual rainfall but are depressed when
annual rainfall is low, or the variance in annual rainfall is high. Perturbation analyses from both the time-invariant and
stochastic models indicate that recruitment and survival of older females are key determinants of population growth rate. 相似文献
507.
Vieites DR Chiari Y Vences M Andreone F Rabemananjara F Bora P Nieto-Román S Meyer A 《Molecular ecology》2006,15(6):1617-1625
Mantella bernhardi is an endemic species of Malagasy poison frog threatened by loss and fragmentation of its natural habitat and collection for the pet trade. It is classified as threatened according to the International Union for Conservation of Nature and Natural Resources (IUCN) categories and included in Appendix II of the Convention on the International Trade of Endangered Species (CITES). A recent survey has increased the known distributional range of the species from one to eight populations across southeastern Madagascar, but little is known about its biology and genetic diversity. Here we estimate inter- and intrapopulation mitochondrial genetic variation of four populations. Populations from the northern and southern parts of the distributional range showed a high degree of divergence (maximum of 11.35% in cytochrome b) and were recovered as reciprocally monophyletic groups. Nine haplotypes were detected in the northern and 12 in the southern populations. The population from Ranomafana National Park showed the lowest number of haplotypes and nucleotide diversity, and shared its most common haplotype with the second northern population from Tolongoina. All the other detected haplotypes were unique to each of the four populations. This suggests the existence of important barriers to gene flow, pre-dating human colonization of Madagascar at about 2000 years ago, in distinct contrast to other Mantella species that show a high degree of haplotype sharing throughout their range. The continued habitat fragmentation within the distribution range of M. bernhardi prevents any connection between its populations. Our data indicate the existence of at least two different management units for conservation in this species, corresponding to the North and South of its distribution range, and highlight the existence of strong regional endemism in southeastern Madagascar. 相似文献
508.
We review aspects of the distributional patterns of Malagasy scorpions belonging to the endemic genus Pseudouroplectes (family Buthidae), restricted to dry forests formations in the south and southwest. One species is described here as new to science. We propose that the observed distributional pattern of members of this genus is not only a consequence of recent ecological features of the landscape, but also of historical biogeographical factors associated with the antiquity of this scorpion lineage. 相似文献
509.
Chouteau P 《Comptes rendus biologies》2006,329(9):691-701
I studied the foraging ecology of Coquerel's Coua (Coua coquereli) and Giant Coua (Coua gigas), which occur in the dry forest in west Madagascar. This kind of forest is characterised by an alternating of a dry and a rainy season. The foraging behaviour was described in several dimensions: i.e. height and proportion of perching, rate of capture (estimating the food availability), foraging techniques, substrates used, type and size of the captured prey. Their foraging behaviour was different according to the season and to the proximity of water. Habitat structure was important to take in consideration to study their foraging behaviour. They tended to use the same pattern of techniques and substrates, but differed by the proportions they used these variables and also by the possibility to climb into the dense understorey vegetation. Seasonal variation has probably an important effect on the prey availability and the nature of prey captured. The diet of both species is also discussed. I suggest that change in habitat structure and resources levels could be important to take in consideration for the conservation of these forest birds. 相似文献
510.
GILBERT RAKOTOARISOA GARY E. SHORE SUSIE M. MCGUIRE SHANNON E. ENGBERG JR EDWARD E. LOUIS RICK A. BRENNEMAN 《Molecular ecology resources》2006,6(4):1122-1125
The Verreaux's sifaka (Propithecus verreauxi) is one of the species of Propithecus, living in the dry forest of southwest Madagascar. This species is endangered due to the loss and fragmentation of its natural habitat, a consequence of deforestation. Thirteen novel nuclear microsatellite loci were isolated and characterized in three populations of Verreaux's sifaka. The marker suite proved informative with an average of 8.9 alleles per locus and observed heterozygosity across the three populations of 0.675. 相似文献