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81.
82.
Effects of single and multiple herbivory by host and non‐host caterpillars on the attractiveness of herbivore‐induced volatiles of sugarcane to the generalist parasitoid Cotesia flavipes
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Maria Fernanda G.V. Peñaflor Felipe G. Gonçalves Camila Colepicolo Patricia A. Sanches José Mauricio S. Bento 《Entomologia Experimentalis et Applicata》2017,165(1):83-93
It is well known that parasitoids are attracted to volatiles emitted by host‐damaged plants; however, this tritrophic interaction may change if plants are attacked by more than one herbivore species. The larval parasitoid Cotesia flavipesCameron (Hymenoptera: Braconidae) has been used intensively in Brazil to control the sugarcane borer, Diatraea saccharalisFabricius (Lepidoptera: Pyralidae) in sugarcane crops, where Spodoptera frugiperda (JE Smith) (Lepidoptera: Noctuidae), a non‐stemborer lepidopteran, is also a pest. Here, we investigated the ability of C. flavipes to discriminate between an unsuitable host (S. frugiperda) and a suitable host (D. saccharalis) based on herbivore‐induced plant volatiles (HIPVs) emitted by sugarcane, and whether multiple herbivory (D. saccharalis feeding on stalk + S. frugiperda feeding on leaves) in sugarcane affected the attractiveness of HIPVs to C. flavipes. Olfactometer assays indicated that volatiles of host and non‐host‐damaged plants were attractive to C. flavipes. Even though host‐ and non‐host‐damaged plants emitted considerably different volatile blends, neither naïve nor experienced wasps discriminated suitable and unsuitable hosts by means of HIPVs emitted by sugarcane. With regard to multiple herbivory, wasps innately preferred the odor blend emitted by sugarcane upon non‐host + host herbivory over host‐only damaged plants. Multiple herbivory caused a suppression of some volatiles relative to non‐host‐damaged sugarcane that may have resulted from the unaltered levels of jasmonic acid in host‐damaged plants, or from reduced palatability of host‐damaged plants to S. frugiperda. In conclusion, our study showed that C. flavipes responds to a wide range of plant volatile blends, and does not discriminate host from non‐host and non‐stemborer caterpillars based on HIPVs emitted from sugarcane. Moreover, we showed that multiple herbivory by the sugarcane borer and fall armyworm increases the attractiveness of sugarcane plants to the parasitoids. 相似文献
83.
ecospat: an R package to support spatial analyses and modeling of species niches and distributions
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Valeria Di Cola Olivier Broennimann Blaise Petitpierre Frank T. Breiner Manuela D'Amen Christophe Randin Robin Engler Julien Pottier Dorothea Pio Anne Dubuis Loic Pellissier Rubén G. Mateo Wim Hordijk Nicolas Salamin Antoine Guisan 《Ecography》2017,40(6):774-787
The aim of the ecospat package is to make available novel tools and methods to support spatial analyses and modeling of species niches and distributions in a coherent workflow. The package is written in the R language (R Development Core Team) and contains several features, unique in their implementation, that are complementary to other existing R packages. Pre‐modeling analyses include species niche quantifications and comparisons between distinct ranges or time periods, measures of phylogenetic diversity, and other data exploration functionalities (e.g. extrapolation detection, ExDet). Core modeling brings together the new approach of ensemble of small models (ESM) and various implementations of the spatially‐explicit modeling of species assemblages (SESAM) framework. Post‐modeling analyses include evaluation of species predictions based on presence‐only data (Boyce index) and of community predictions, phylogenetic diversity and environmentally‐constrained species co‐occurrences analyses. The ecospat package also provides some functions to supplement the ‘biomod2’ package (e.g. data preparation, permutation tests and cross‐validation of model predictive power). With this novel package, we intend to stimulate the use of comprehensive approaches in spatial modelling of species and community distributions. 相似文献
84.
85.
Renato Lahos Romano Cleber Wanderlei Liria M. Terêsa Machini Pio Colepicolo Leonardo Zambotti-Villela 《Journal of applied phycology》2017,29(2):811-820
The toxic effects of metals on the aquatic environment are documented and well known. Metals are able to unbalance the intracellular redox potential and, therefore, induce the oxidative stress in living organisms. In this study, the responses of glutathione [reduced (GSH) and oxidized (GSSG)] and the structurally GSH-related peptides phytochelatins 3 and 4 (PC3 and PC4) were examined in the marine dinoflagellate Lingulodinium polyedrum exposed to cadmium (Cd). A novel method for PC3 and PC4 synthesis is described here based on a Boc strategy, yielding peptides with purities higher than 97 %. Analytical detection of GSH, GSSG, PC3, and PC4 applying liquid chromatography-tandem mass spectrometry (LC-MS/MS) method had been developed and described as robust and accurate with a detection limit of nmol g?1 dry weight (DW) for PC3 and PC4. The intracellular levels of GSH and GSSG decreased dramatically over 24 and 48-h exposure to 18 μmol L?1 Cd. These decreases were followed by the enhancement of intracellular PC3 and PC4 levels, in which syntheses started to be detected after 2 and 8-h exposure, respectively. Moreover, the PC4/PC3 ratio reached its maximum over 24-h exposure, being 8 to 75-fold higher than the one observed for other microalgae. This seems to be an efficient strategy of L. polyedrum to be protected against Cd environment contamination, since PC4 has more chelating sites and is structurally more stable than PC2 and PC3, the most abundant for other microalgae. 相似文献
86.
Claudio M. P. Pereira Camila F. P. Nunes Leonardo Zambotti-Villela Nivia M. Streit Daiane Dias Ernani Pinto Carolina B. Gomes Pio Colepicolo 《Journal of applied phycology》2017,29(2):751-757
This study reports for the first time the extraction and quantification of sterols in six species of brown macroalgae from Antarctica: Adenocystis utricularis, Ascoseira mirabilis, Cystosphaera jacquinotii, Desmarestia anceps, Desmarestia antarctica, and Himantothallus grandifolius. Ultrasound irradiation was used as a promotor to extract sterols from algal biomass. The extracts were analyzed by high-performance liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) for sterol quantization (ergosterol, brassicasterol, fucosterol, β-sitosterol, campesterol, cholesterol, and stigmasterol). In general, fucosterol was the most abundant (6.60 to 48.13 mg kg?1), followed by β-sitosterol (5.29 to 16.49 mg kg?1), stigmasterol (2.69 to 14.84 mg kg?1) in five of the six examined algae. The sterol campesterol was found in lower concentrations (0.07 to 0.15 mg kg?1) in all studied samples. 相似文献
87.
Harry R. Chobanian Yan Guo Barbara Pio Haifeng Tang Nardos Teumelsan Matthew Clements Jessica Frie Ronald Ferguson Zach Guo Brande S. Thomas-Fowlkes John P. Felix Jessica Liu Martin Kohler Birgit Priest Caryn Hampton Lee-Yuh Pai Aaron Corona Joseph Metzger Alexander Pasternak 《Bioorganic & medicinal chemistry letters》2017,27(4):1109-1114
A spirocyclic class of ROMK inhibitors was developed containing a structurally diverse heterocyclic sulfone moiety and spirocyclic core starting from lead 1. These compounds not only displayed exquisite ROMK potency but significantly improved selectivity over hERG. The lead compounds were found to have favorable pharmacokinetic properties and displayed robust diuretic, natriuretic and blood pressure lowering effects in spontaneously hypertensive rats. 相似文献
88.
Bessem Chouaia Nizar Goda Giuseppe Mazza Sumer Alali Fiorella Florian Fabrizia Gionechetti Matteo Callegari Elena Gonella Giulia Magoga Marco Fusi Elena Crotti Daniele Daffonchio Alberto Alma Francesco Paoli Pio Federico Roversi Leonardo Marianelli Matteo Montagna 《Environmental microbiology》2019,21(11):4343-4359
Popillia japonica Newman (Coleoptera: Scarabaeidae) is a highly polyphagous invasive beetle originating from Japan. This insect is highly resilient and able to rapidly adapt to new vegetation. Insect-associated microorganisms can play important roles in insect physiology, helping their hosts to adapt to changing conditions and potentially contributing to an insect's invasive potential. Such symbiotic bacteria can be part of a core microbiota that is stably transmitted throughout the host's life cycle or selectively recruited from the environment at each developmental stage. The aim of this study was to investigate the origin, stability and turnover of the bacterial communities associated with an invasive population of P. japonica from Italy. Our results demonstrate that soil microbes represent an important source of gut bacteria for P. japonica larvae, but as the insect develops, its gut microbiota richness and diversity decreased substantially, paralleled by changes in community composition. Notably, only 16.75% of the soil bacteria present in larvae are maintained until the adult stage. We further identified the micro-environments of different gut sections as an important factor shaping microbiota composition in this species, likely due to differences in pH, oxygen availability and redox potential. In addition, P. japonica also harboured a stable bacterial community across all developmental stages, consisting of taxa well known for the degradation of plant material, namely the families Ruminococcacae, Christensenellaceae and Lachnospiraceae. Interestingly, the family Christensenallaceae had so far been observed exclusively in humans. However, the Christensenellaceae operational taxonomic units found in P. japonica belong to different taxonomic clades within this family. 相似文献
89.
From April of 2000 to May of 2003, 28 consecutive patients with chronic osteomyelitis of the lower extremity underwent surgical debridement and reconstruction with anterolateral thigh perforator flaps (six cases were combined with vastus lateralis muscle flaps). All wounds were open for a minimum period of 6 weeks (average, 24.7 months; range, 6 weeks to 52 months). The average patient age was 42.8 years (range, 18 to 71 years), there were 21 male and seven female patients, and the average follow-up period was 18.2 months (range, 5 to 41 months). The cause of injury was an open fracture in 10 cases, secondary wound complications after reduction in eight cases, and diabetic foot in 10 cases. The surface defects ranged from 50 to 153 cm. The wounds were debrided an average of 2.5 times and then reconstructed with flap and treated with antibiotics for 6 weeks. Antibiotic beads were used in six cases and secondary bone graft procedures were performed in seven cases 3 months after the flap coverage. All 28 flaps were successful without any signs of recurrences or persistent osteomyelitis, but partial wound dehiscence was observed during early rehabilitation in two cases suspected of delayed healing caused by diabetes. These wounds healed spontaneously. All patients achieved acceptable gait function after rehabilitation. No debulking procedure was necessary in any case. Although the muscle flap is known to provide superior vascular supply, the type of flap used for coverage seems to be less critical in the final outcome, provided that total debridement and obliteration of dead spaces are achieved. A well-vascularized anterolateral thigh perforator flap was successfully used to combat infection and bring stability to wounds with chronic osteomyelitis. 相似文献
90.
Conformational flexibility and crystallization of tandemly linked type III modules of human fibronectin.
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A. Lombardo Y. Wang C. Z. Ni X. Dai C. D. Dickinson R. Kodandapani S. Chiang C. A. White F. Pio N. H. Xuong R. C. Hamlin E. Ruoslahti K. R. Ely 《Protein science : a publication of the Protein Society》1996,5(9):1934-1938
Fibronectin is a large cell adhesion molecule that is composed of several functional domains. The cell-binding domain that binds to cell surface integrins consists of repeated homologous type III modules. In this study, recombinant fragments from the cell-binding domain of human fibronectin that participate in a newly characterized fibronectin-fibronectin interaction with FNIII1 were crystallized. In each case, the crystals had more than one fibronectin fragment in the asymmetric unit. Crystals of FNIII10-11 grew in the space group C2 with a = 117.1 A, b = 38.6 A, c = 80.6 A, beta = 97.2 degrees, and two molecules in the asymmetric unit. These crystals diffracted to 2.5 A resolution. Fragment FNIII8-11 and a shorter fragment, FNIII8-10, crystallized in hexagonal space groups with large unit cells and two to four molecules per asymmetric unit. Even very large crystals of these fragments did not diffract beyond 4 A. The crystal packing for this collection of fibronectin fragments suggests conformational flexibility between linked type III modules. The functional relevance of this flexibility for elongated versus compact models of the cell-binding domain of fibronectin is discussed. 相似文献