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551.
Seed coat sculpture in Comanthera (Eriocaulaceae) and its implications on taxonomy and phylogenetics
Leilane C. Barreto Livia Echternacht Queila S. Garcia 《Plant Systematics and Evolution》2013,299(8):1461-1469
Eriocaulaceae occurs primarily in the Neotropics, diversifying mostly in mountainous areas in southeastern Brazil. They are popularly known as everlasting plants, because once dried, they retain the appearance of living structures, being widely used as ornamentals. Most of the commercialized species belong to the genus Comanthera L.B.Sm., which was reestablished from Syngonanthus Ruhland. Comanthera groups 41 species, 26 in Comanthera subg. Comanthera and 15 in C. subg. Thysanocephalus, all restricted to South America. Phylogenetic analyses show Syngonanthus and Comanthera, as well as both Comanthera subgenera, as monophyletic and sister groups. Seed coat ornamentation proved to be useful and informative to help in determining taxonomic relationships in many plant groups. This study aims to characterize the external morphology of the seed coat of Comanthera and its subgenera using scanning electron microscopy, and discuss its taxonomic and phylogenetic implications. Seeds from nine species of Comanthera were analyzed, seven of which belong to C. subg. Comanthera and two to C. subg. Thysanocephalus. The results were compared with four species of Syngonanthus and one of Leiothrix. In Comanthera and Leiothrix the external periclinal walls remain intact, whereas they degenerate in the remaining genera. However, seed coat ornamentation in Leiothrix and Comanthera has distinct origins, as in the former, it comes from projections of the external layer of the outer integument, forming a striate pattern, and in the latter, from projections of the inner layer, conferring a rough pattern. Comanthera subg. Comanthera shows a rugose undulatory pattern, whilst C. subg. Thysanocephalus has a rugose micropapillate pattern. The newly reported features of the seed coat provide support for the Comanthera subgenera, thus presenting taxonomic and phylogenetic value. 相似文献
552.
Julia Rodrigues Barreto Erika Berenguer Joice Ferreira Carlos A. Joly Yadvinder Malhi Marina Maria Moraes de Seixas Jos Barlow 《Ecology and evolution》2021,11(9):4012
- Studies on the effects of human‐driven forest disturbance usually focus on either biodiversity or carbon dynamics but much less is known about ecosystem processes that span different trophic levels. Herbivory is a fundamental ecological process for ecosystem functioning, but it remains poorly quantified in human‐modified tropical rainforests.
- Here, we present the results of the largest study to date on the impacts of human disturbances on herbivory. We quantified the incidence (percentage of leaves affected) and severity (the percentage of leaf area lost) of canopy insect herbivory caused by chewers, miners, and gall makers in leaves from 1,076 trees distributed across 20 undisturbed and human‐modified forest plots in the Amazon.
- We found that chewers dominated herbivory incidence, yet were not a good predictor of the other forms of herbivory at either the stem or plot level. Chewing severity was higher in both logged and logged‐and‐burned primary forests when compared to undisturbed forests. We found no difference in herbivory severity between undisturbed primary forests and secondary forests. Despite evidence at the stem level, neither plot‐level incidence nor severity of the three forms of herbivory responded to disturbance.
- Synthesis. Our large‐scale study of canopy herbivory confirms that chewers dominate the herbivory signal in tropical forests, but that their influence on leaf area lost cannot predict the incidence or severity of other forms. We found only limited evidence suggesting that human disturbance affects the severity of leaf herbivory, with higher values in logged and logged‐and‐burned forests than undisturbed and secondary forests. Additionally, we found no effect of human disturbance on the incidence of leaf herbivory.
553.
Visnu C. Sarmento Aliny F. S. Barreto Paulo J. P. Santos 《Biodiversity and Conservation》2013,22(11):2645-2663
The present study experimentally determined the short-term effect of different trampling intensities on the phytal habitat and associated meiofauna, and assessed the recovery of these communities on a coral reef. The experiment was conducted within the protected area on the reef of Porto de Galinhas Beach, northeastern Brazil. Within three areas, 30 × 30 cm2 plots were subjected to different experimental trampling intensities: 0 (control), 32 (low intensity) and 79 (high intensity) footsteps applied during 3 consecutive days. Samples were taken before trampling started and then 1 day and 1, 2 and 3 months after the end of trampling. Multivariate and univariate analyses were used to test for changes in the phytal substrate, the densities of the main meiofaunal major taxa, and the diversity, comparing the trampling intensities and the time periods. The immediate impact of trampling negatively affected the phytal substrate, causing large reductions in sediment content, total substrate weight, and algal turf height. Trampling also drastically decreased the density of the associated meiofauna and modified the community structure. The major meiofauna groups showed different patterns of recovery during the first and second months. However, 3 months after trampling ended, no impact was found for densities of total meiofauna and for most major taxa, and no differences were observed in the community structure among all trampling intensities. Finally, the results for trampling susceptibility and resilience allowed us to extend the discussion to management strategies for the use of reef areas for recreation. 相似文献
554.
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556.
B. Almeida H. Kjeldal I. Lolas A. D. Knudsen G. Carvalho K. L. Nielsen M. T. Barreto Crespo A. Stensballe J. L. Nielsen 《Biodegradation》2013,24(5):615-630
Ibuprofen is the third most consumed pharmaceutical drug in the world. Several isolates have been shown to degrade ibuprofen, but very little is known about the biochemistry of this process. This study investigates the degradation of ibuprofen by Patulibacter sp. strain I11 by quantitative proteomics using a metabolic labelling strategy. The whole-genome of Patulibacter sp. strain I11 was sequenced to provide a species-specific protein platform for optimal protein identification. The bacterial proteomes of actively ibuprofen-degrading cells and cells grown in the absence of ibuprofen was identified and quantified by gel based shotgun-proteomics. In total 251 unique proteins were quantitated using this approach. Biological process and pathway analysis indicated a number of proteins that were up-regulated in response to active degradation of ibuprofen, some of them are known to be involved in the degradation of aromatic compounds. Data analysis revealed that several of these proteins are likely involved in ibuprofen degradation by Patulibacter sp. strain I11. 相似文献
557.
Tumoral pancreatic islet cells of the RINm5F line are equipped with two classes of [3H]cytochalasin B binding sites with respective Kd of 0.4 and 7 microM. The binding of the fungal metabolite and its dissociation from the binding sites display rapid time courses. The binding is inhibited by D-glucose, more than by L-glucose, by phlorizin and by cytochalasin E. These findings are considered in the light of the dual action of cytochalasin B upon hexose transport and motile activity in islet cells. 相似文献
558.
Fred Bernardes Filho Claudia Maria Lincoln Silva Glauber Voltan Marcel Nani Leite Ana Laura Rosifini Alves Rezende Natlia Aparecida de Paula Josaf Gonalves Barreto Norma Tiraboschi Foss Marco Andrey Cipriani Frade 《PLoS neglected tropical diseases》2021,15(6)
BackgroundThis study evaluates implementation strategies for leprosy diagnosis based on responses to a Leprosy Suspicion Questionnaire (LSQ), and analyzes immunoepidemiological aspects and follow-up of individuals living in a presumptively nonendemic area in Brazil.Methodology/Principal findingsQuasi-experimental study based on LSQ throughout Jardinópolis town by community health agents, theoretical-practical trainings for primary care teams, dermatoneurological examination, anti-PGL-I serology, RLEP-PCR, and spatial epidemiology. A Leprosy Group (LG, n = 64) and Non-Leprosy Group (NLG, n = 415) were established. Overall, 3,241 LSQs were distributed; 1,054 (32.5%) LSQ were positive for signs/symptoms (LSQ+). Among LSQ+ respondents, Q2-Tingling (pricking)? (11.8%); Q4-Spots on the skin? (11.7%); Q7-Pain in the nerves? (11.6%); Q1-Numbness in your hands and/or feet? (10.7%) and Q8-Swelling of hands and feet? (8.5%) were most frequently reported symptoms. We evaluated 479 (14.8%) individuals and diagnosed 64 new cases, a general new case detection rate (NCDR) of 13.4%; 60 were among 300 LSQ+ (NCDR-20%), while 4 were among 179 LSQ negative (NCDR-2.23%). In LG, Q7(65%), Q2(60%), Q1(45%), Q4(40%) and Q8(25%) were most frequent. All 2x2 crossings of these 5 questions showed a relative risk for leprosy ranging from 3 to 5.8 compared with NLG. All patients were multibacillary and presented hypochromatic macules with loss of sensation. LG anti-PGL-I titers were higher than NLG, while 8.9% were positive for RLEP-PCR. The leprosy cases and anti-PGL-I spatial mappings demonstrated the disease spread across the town.Conclusions/SignificanceImplementation actions, primarily LSQ administration focused on neurological symptoms, indicate hidden endemic leprosy in a nonendemic Brazilian state. 相似文献
559.
M G Fauth K P Barreto G F Wassermann 《Comparative biochemistry and physiology. A, Comparative physiology》1991,98(3-4):513-515
1. Insulin stimulated the [1-14C] methylaminoisobutyric acid and [1-14C] aminoisobutyric acid uptake in the bovine adrenal cortex or in the glomerulosa zone through the A system. 2. Verapamil nullified the insulin stimulatory action indicating that this hormonal action is probably related to the voltage-dependent Ca2+ channels. 相似文献
560.