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991.
992.
This paper describes the morphology of the immature stages (egg, larva and pupa) and larval behavior of the butterfly Hermeuptychia atalanta, a common and widespread species of satyrinae in South America. Eggs are white and spherical, laid singly on leaves of grasses. The first instar has a light-green body and dark-brown head; all remaining instars present body and head capsule light green. Larvae have no spines, and general morphology is similar to other species of the subtribe Euptychiina.  相似文献   
993.
Studies on phytoplankton production conducted in lakes of the middle Rio Doce basin demonstrated significant diurnal and seasonal variations with high phytoplankton production rates recorded in the morning hours during the dry periods. Bacterial production data for these lakes had not been recorded until now. The present study had as working hypothesis that bacterial production may contribute significantly to carbon fixation, particularly in lakes rich in organic matter and that this production varies diurnal and seasonally thus altering BP/PP ratios. In order to test this hypothesis the study had as objective to estimate phytoplankton and bacterioplankton production rates along with the concentrations of carbon, nitrogen, and phosphorus in two periods of the day (morning and afternoon) and in two seasons (dry and rainy), in four lakes, being two lakes within the Rio Doce State Park and two at its surroundings. Among the selected lakes, Lake Amarela showed the highest nutrient concentrations and highest bacterial production. The results allow to conclude that despite exhibiting lower values when compared with the ones recorded for phytoplankton production, bacterioplankton production is essential to the general metabolism of the lakes, particularly for those rich in organic matter and exhibiting oligo-mesotrophic conditions.  相似文献   
994.
Skin secretion of Hypsiboas punctatus is the source of a complex mixture of bioactive compounds where peptides and small proteins prevail, similarly to many other amphibians. Among dozens of molecules isolated from H. punctatus in a proteomic based approach, we report here the structural and functional studies of a novel peptide named Phenylseptin (FFFDTLKNLAGKVIGALT-NH2) that was purified as two naturally occurring D- and L-Phes configurations. The amino acid epimerization and C-terminal amidation for both molecules were confirmed by a combination of techniques including reverse-phase UFLC, ion mobility mass spectrometry, high resolution MS/MS experiments, Edman degradation, cDNA sequencing and solid-phase peptide synthesis. RMSD analysis of the twenty lowest-energy 1H NMR structures of each peptide revealed a major 90° difference between the two backbones at the first four N-terminal residues and substantial orientation changes of their respective side chains. These structural divergences were considered to be the primary cause of the in vitro quantitative differences in antimicrobial activities between the two molecules. Finally, both molecules elicited equally aversive reactions in mice when delivered orally, an effect that depended entirely on peripheral gustatory pathways.  相似文献   
995.
Nonsense-mediated mRNA decay (NMD) is a surveillance pathway that recognizes and selectively degrades mRNAs carrying premature termination codons (PTCs). The level of sensitivity of a PTC-containing mRNA to NMD is multifactorial. We have previously shown that human β-globin mRNAs carrying PTCs in close proximity to the translation initiation AUG codon escape NMD. This was called the ‘AUG-proximity effect’. The present analysis of nonsense codons in the human α-globin mRNA illustrates that the determinants of the AUG-proximity effect are in fact quite complex, reflecting the ability of the ribosome to re-initiate translation 3′ to the PTC and the specific sequence and secondary structure of the translated ORF. These data support a model in which the time taken to translate the short ORF, impacted by distance, sequence, and structure, not only modulates translation re-initiation, but also impacts on the exact boundary of AUG-proximity protection from NMD.  相似文献   
996.
Microalgal triglycerides (TAGs) represent a sustainable feedstock for food, chemical and biofuel industries. The operational strategy (batch, semi-continuous, continuous cultivations) has an impact on the TAG productivity. In this study, semi-continuous (i.e. with fixed harvesting frequency) and batch cultivations were compared on TAG production both at lab-scale and in outdoor cultivations. At lab-scale, the semi-continuous TAG productivity was highest for a cycle time of 2 days (SC1; 0.21 g L?1 day?1) and similar to the maximum obtained with the batch (optimal harvest time; 0.23 g L?1 day?1). Although TAG content was lower for SC1 (22 %) than for the batch (35 %), higher biomass productivities were obtained with SC1. Outdoors, semi-continuous cultivations were subjected to a lower degree of stress (i.e. higher amount of nitrogen present in the system relative to the given irradiance) compared to lab-scale. This yielded low and similar TAG contents (10–13 %) in the different semi-continuous runs that were outdone by the batch on both TAG content (15–25 %) and productivity (batch, 0.97–2.46 g m?2 day?1; semi-continuous, 0.35–0.85 g m?2 day?1). The lab-scale experiments showed that semi-continuous strategies, besides leading to similar TAG productivities compared to the batch, could make TAG production cost effective by valorising also non-TAG compounds. However, optimization of outdoor semi-continuous cultivations is still required. For instance, the nitrogen supply and the harvest frequency should be adjusted on the total irradiance. Additionally, future research should focus on recovery metabolism upon nitrogen resupply.  相似文献   
997.
Cutaneous leishmaniasis (CL) in the state of Rio de Janeiro is sporadic and can be characterised as a peridomestic transmission that occurs in modified natural environments. The aim of this work was to study the fauna and ecological characteristics of sandflies in an environmentally protected area (the State Park of Serra da Tiririca) within the remnants of the Atlantic Forest in the municipalities of Niterói and Maricá and their possible relationship with leishmaniasis. Captures were performed using light traps during the night once a month for one year in both sylvatic environments and areas surrounding homes near the park. A total of 1,037 sandflies were captured, belonging to nine genera and 12 species: Evandromyia tupynambai (34.1%), Migonemyia migonei (20.6%), Brumptomyia cunhai (13.8%), Micropygomyia schreiberi (9.7%), Psathyromyia lanei (6.5%), Brumptomyia nitzulescui (5.7%), Evandromyia edwardsi (5.4%), Nyssomyia intermedia (2.8%), Evandromyia cortelezzii (0.6%), Pintomyia bianchigalatiae (0.5%), Lutzomyia longipalpis (0.2%) and Sciopemyia microps (0.1%). Both Mg. migonei and Ny. intermedia may be acting as vectors of CL in this area.  相似文献   
998.
Butterflies and moths are found in all terrestrial environments and require efforts for a better understanding of its mega-diversity. These taxa have been the subject of several studies involving phylogeny, ecology and environmental impacts. Nevertheless, several areas in the tropics remain unexplored, resulting in gaps in the taxonomic composition and distribution of butterflies in endemic environments. Therefore, a survey of the butterfly fauna of the Bodoquena Plateau in Brazil was conducted. This area consists of tropical Atlantic Forests, with marginal influences of Savannah, Chaco and Pantanal. Sampling was carried out in 20 locations using Van Someren Rydon traps and insect nets between November 2009 and April 2015. Active collection of individuals was conducted from 9:00 to 17:00h, totaling 240 hours of sampling effort. In total, we registered 768 individuals belonging to 146 species of 98 genera, six families and 18 subfamilies. Nymphalidae was the richest family (84 species), followed by Hesperiidae (22 species), Riodinidae (14 species), Pieridae (12) Papilionidae (11 species) and Lycaenidae (five species). We sampled 239 nymphalids in traps, with 48 species, 30 genera, 15 tribes and five subfamilies. The most common species were Eunica macris (Godart, 1824), Dynamine artemisia (Fabricius, 1793) and Memphis moruus (Fabricius, 1775). Therefore, this study contributes to the knowledge of the Neotropical butterfly diversity and distribution, providing 37 new records and supporting the use of wildlife inventories as important tools for the knowledge of tropical forests biodiversity and conservation.  相似文献   
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