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961.
M. H. Urbani C. L. Quarin F. Espinoza M. I. O. Penteado I. F. Rodrigues 《Plant Systematics and Evolution》2002,236(1-2):99-105
Paspalum simplex is a grass distributed throughout the phytogeographic Chaco region in South America from which sexual diploid and apomictic
tetraploid races have been reported. We analysed native populations to determine their homogeneity of ploidy level, and the
relationship between geographic distribution, ploidy levels, and reproductive systems. The ploidy level was established for
379 plants from 32 wild populations. Tetraploidy and apomixis constitute the most common combination for this species all
over the Chaco region. Apomictic hexaploid plants were found associated with 4x populations. Diploids were confined to a small
sector of the region. One sexual triploid plant arose from seed harvested in a pure 2x population, and one apomictic 3x plant
was found in a mixed 2x-4x population. The results suggest that P. simplex is a core agamic complex characteristic of the Chaco region from which other apomictic polyploid species of the subgenus
Anachyris could have evolved.
Received July 24, 2002; accepted September 12, 2002 Published online: December 11, 2002 相似文献
962.
Joana D. Amaral Ricardo J. S. Viana Rita M. Ramalho Clifford J. Steer Cec��lia M. P. Rodrigues 《Journal of lipid research》2009,50(9):1721-1734
Bile acids are a group of molecular species of acidic steroids with peculiar physical-chemical and biological characteristics. At high concentrations they become toxic to mammalian cells, and their presence is pertinent in the pathogenesis of several liver diseases and colon cancer. Bile acid cytoxicity has been related to membrane damage, but also to nondetergent effects, such as oxidative stress and apoptosis. Strikingly, hydrophilic ursodeoxycholic acid (UDCA), and its taurine-conjugated form (TUDCA), show profound cytoprotective properties. Indeed, these molecules have been described as potent inhibitors of classic pathways of apoptosis, although their precise mode of action remains to be clarified. UDCA, originally used for cholesterol gallstone dissolution, is currently considered the first choice therapy for several forms of cholestatic syndromes. However, the beneficial effects of both UDCA and TUDCA have been tested in other experimental pathological conditions with deregulated levels of apoptosis, including neurological disorders, such as Alzheimer''s, Parkinson''s, and Huntington''s diseases. Here, we review the role of bile acids in modulating the apoptosis process, emphasizing the anti-apoptotic effects of UDCA and TUDCA, as well as their potential use as novel and alternate therapeutic agents for the treatment of apoptosis-related diseases. 相似文献
963.
Global changes in pampean lowland streams (Argentina): implications for biodiversity and functioning
The rivers and streams in the pampean plains are characterized by a low flow rate due to the low slope of the surrounding
terrain, high levels of suspended solids, silty sediment in the benthos, and reduced rithron; the riparian forest of this
region has been replaced by low-altitude grasslands. Many of these environments contain a wide coverage of aquatic reeds,
both submerged and floating, making the pampas limologically extraordinary. These terrains have undergone a gradual transformation
in response to the progress of urbanization and agricultural activity in recent years with a resulting loss of biodiversity,
leaving only few sites that continue to reflect the original characteristics of the region. Because of human activities in
combination with the global climate change, variations have occurred in biological communities that are reflected in the structure
and function of populations and assemblages of algae, macrophytes, and invertebrate fauna or in the eutrophication of affected
ecosystems. The objective of this article is to describe the principal limnologic characteristics of the streams that traverse
the Buenos Aires Province and relate these features with the predicted future global changes for the area under study. Considering
the future climate-change scenarios proposed for the pampean region, the projected increment in rainfall will affect the biological
communities. Higher rainfall may enhance the erosion and generate floodings; increasing the transport of sediments, nutrients,
and contaminants to the ocean and affecting the degree of water mineralization. Changes in discharge and turbidity may affect
light penetration in the water column as well as its residence time. The modifications in the use of the soil will probably
favor the input of nutrients. This latter effect will favor autotrophy, particularly by those species capable of generating
strategies for surviving in more turbid and enriched environments. An accelerated eutrophication will change the composition
of the consumers in preference to herbivores and detritivores. The increase in global population projected for the next years
will demand more food, and this situation coupled with the new scenarios of climate change will lead to profound socioeconomic
changes in the pampean area, implying an increase in demand for water resources and land uses. 相似文献
964.
965.
Jssica Freitas Araújo Encinas Carlos Henrique Foncesca Matheus Moreira Perez Diogo Pimenta Simes Beatriz da Costa Aguiar Alves Marcelo Rodrigues Bacci Laura Beatriz Mesiano Maifrino Fernando Luiz Affonso Fonseca Glaucia Luciano da Veiga 《Cell biochemistry and function》2019,37(6):443-451
Renal cells need oxygen for homeostasis; it is known for adjusting cellular functioning and the energy obtainment have a broad relationship with cellular respiration, through the O2 bioavailability. O2 homeostasis regulation in the kidney is mediated by hypoxia‐inducible factors (HIFs). HIF is divided into three α isoforms, represented by HIF‐1α, HIF‐2α, and HIF‐3α in addition to three paralogs of HIF‐1β; these are involved in some metabolic processes, as well as in the pathogenesis of several diseases. Renal biopsy analyses of patients and experimental animal models aim to understand the relationship between HIF and protection against developing renal diseases or the induction of their onset, being thus this molecule can be considered a potential biomarker of renal disease. We carried out a systematic review to which we included studies on HIF‐1α and renal disease in the last 5 years (2013‐2018) in researches with humans and/or animal model through searches in three databases: LILACS, PubMed, and SciELO by two researchers. We obtained 22 articles that discussed the relationship with HIF as inductor or protector against renal disease and no relation between HIF and renal. We observed controversies remain regarding the relation between of HIF with renal diseases; this may be related to the different intracellular pathways mediated by HIF‐1α, thereby determining differentiated cellular responses. 相似文献
966.
Vania Cristina Desoti Danielle Lazarin-Bidóia Fabianne Martins Ribeiro Solange Cardoso Martins Jean Henrique da Silva Rodrigues Tania Ueda-Nakamura Celso Vataru Nakamura Valdecir Farias Ximenes Sueli de Oliveira Silva 《PloS one》2015,10(12)
Chagas’ disease is an infection that is caused by the protozoan Trypanosoma cruzi, affecting millions of people worldwide. Because of severe side effects and variable efficacy, the current treatments for Chagas’ disease are unsatisfactory, making the search for new chemotherapeutic agents essential. Previous studies have reported various biological activities of naphthoquinones, such as the trypanocidal and antitumor activity of vitamin K3. The combination of this vitamin with vitamin C exerted better effects against various cancer cells than when used alone. These effects have been attributed to an increase in reactive oxygen species generation. In the present study, we evaluated the activity of vitamin K3 and vitamin C, alone and in combination, against T. cruzi. The vitamin K3 + vitamin C combination exerted synergistic effects against three forms of T. cruzi, leading to morphological, ultrastructural, and functional changes by producing reactive species, decreasing reduced thiol groups, altering the cell cycle, causing lipid peroxidation, and forming autophagic vacuoles. Our hypothesis is that the vitamin K3 + vitamin C combination induces oxidative imbalance in T. cruzi, probably started by a redox cycling process that leads to parasite cell death. 相似文献
967.
Thalita G. Barros Jorge A.N. Santos Bruno E.G. de Souza Ana Carolina R. Sodero Alessandra M.T. de Souza Dayane P. da Silva Carlos Rangel Rodrigues Sergio Pinheiro Luiza R.S. Dias Bárbara Abrahim-Vieira Luciano Puzer Estela M.F. Muri 《Bioorganic & medicinal chemistry letters》2017,27(2):314-318
Human kallikrein 1 (KLK1) is the most extensively studied member of this family and plays a major role in inflammation processes. From Ugi multicomponent reactions, isomannide-based peptidomimetic 10 and 13 where synthesized and showed low micromolar values of IC50 for KLK1 The most active compound (10) presented competitive mechanism, with three structural modifications important to interact with active site residues which corroborates its KLK1 inhibition. Finally, the most active compound also showed good ADMET profile, which indicates compound 10 as a potential hit in the search for new KLK1 inhibitors with low side effects. 相似文献
968.
969.
J. T. Magalhes‐Junior A. De A. Oliva‐Filho H. O. Novais P. R. R. Mesquita F. M. Rodrigues M. C. Pinto S. M. Barrouin‐Melo 《Medical and veterinary entomology》2019,33(2):322-325
Lutzomyia longipalpis (Diptera: Psychodidae) is the primary vector of Leishmania infantum (Kinetoplastida: Trypanosomatidae) in the Americas. Studies have been carried out to identify new alternatives for monitoring and controlling this sandfly species, particularly with the use of chemical baits. The attractiveness of odours emitted by foxes and alcohols found in some plants has already been demonstrated in laboratory tests with Lu. longipalpis. However, no studies have evaluated the responses of these insects to volatile organic compounds (VOCs) emitted by dogs. The present study was carried out to investigate the effects on Lu. longipalpis of individual and blends of VOCs identified in hair from dogs infected with L. infantum. Effects in male and female Lu. longipalpis were assessed using wind tunnel methodology. Individual compounds including octanal, nonanal, decanal and heptadecane showed capacity for activating and/or attracting male Lu. longipalpis. Only decanal and nonanal showed effects on females. The combination of octanal, decanal and heptadecane increased activation and attraction behaviour in male sandflies, as did the blend of octanal and decanal. These findings indicate that VOCs emitted by dogs may be an interesting source of new attractants of sandflies. 相似文献
970.
Renan Janke Bosque Jente Ottenburghs Cecília Rodrigues Vieira Fabrícius Maia Chaves Bicalho Domingos 《Evolution; international journal of organic evolution》2020,74(11):2541-2543
Mimicry can directly affect the evolutionary history of models, mimics, and signal receivers. Mimics often use multimodal signaling to deceive receivers. Jamie et al. showed that brood parasitic birds display multimodal signaling of mimetic traits triggered by sexual and filial imprinting on host species. These resulting adaptations can interact with premating isolation barriers to strengthen reproductive isolation and potentially drive sympatric speciation. 相似文献