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901.
The importance of polymerization and galloylation for the antiproliferative properties of procyanidin-rich natural extracts 总被引:1,自引:0,他引:1
Lizarraga D Lozano C Briedé JJ van Delft JH Touriño S Centelles JJ Torres JL Cascante M 《The FEBS journal》2007,274(18):4802-4811
Grape (Vitis vinifera) and pine (Pinus pinaster) bark extracts are widely used as nutritional supplements. Procyanidin-rich fractions from grape and pine bark extract showing different mean degrees of polymerization, percentage of galloylation (percentage of gallate esters) and reactive oxygen species-scavenging capacity were tested on HT29 human colon cancer cells. We observed that the most efficient fractions in inhibiting cell proliferation, arresting the cell cycle in G(2) phase and inducing apoptosis were the grape fractions with the highest percentage of galloylation and mean degree of polymerization. Additionally, the antiproliferative effects of grape fractions were consistent with their oxygen radical-scavenging capacity and their ability to trigger DNA condensation-fragmentation. 相似文献
902.
João Afonso Baptista Monica Truninger 《The journal of the Royal Anthropological Institute》2022,28(2):556-576
Doing research on fishery commodities in Portugal led us to an enigma: for a dead fish to be fresco (fresh) it must be alive. This paradox manifests at a popular, commercial, and legal level. It denotes the interruption of the difference between being dead and being alive in the commodity form. In Portugal, we suggest, the commercialization of peixe fresco (fresh fish) is based on the production and consumption of edible ‘zombis’: seafood corpses technologically and symbolically crafted as undead. An open concept, ‘edible zombis’ is part of an experimental vocabulary that foregrounds the productive agency of undeadness, both biological and commercial, in the seafood economic complex. It relates to the ordinary practice of necromancy in the commodity-based world. Edible zombis are commodity fetishes that fetishize their producers and consumers, suspending them from the capitalist system in which they live. 相似文献
903.
João H. C. Manfrão-Netto Enzo Bento Queiroz Ana C. de Oliveira Junqueira Antônio M. V. Gomes Daniel Gusmão de Morais Hugo Costa Paes Nádia Skorupa Parachin 《Journal of applied microbiology》2022,132(2):822-840
Hyaluronic acid (HA) is a biopolymer of repeating units of glucuronic acid and N-acetylglucosamine. Its market was valued at USD 8.9 billion in 2019. Traditionally, HA has been obtained from rooster comb-like animal tissues and fermentative cultures of attenuated pathogenic streptococci. Various attempts have been made to engineer a safe micro-organism for HA synthesis; however, the HA titres obtained from these attempts are in general still lower than those achieved by natural, pathogenic producers. In this scenario, ways to increase HA molecule length and titres in already constructed strains are gaining attention in the last years, but no recent publication has reviewed the main genetic strategies applied to improve HA production on heterologous hosts. In light of that, we hereby compile the advances made in the engineering of micro-organisms to improve HA synthesis. 相似文献
904.
Ana Beatriz Portes Grazielle Rodrigues Mylenna Palma Leitão Rafaela Ferrari Carlos Adam Conte Junior Pedro Panzenhagen 《Journal of applied microbiology》2022,132(2):872-889
This systematic review focuses on obtaining the most relevant information from multiple studies that detected a mobilized colistin resistance mcr gene in Salmonella for a better comprehension of its global distribution. A group of strategic and systematic keywords were combined to retrieve research data on the detection frequency of the mcr gene globally from four database platforms (Google Scholar, Science Direct, PubMed and Scielo). Forty-eight studies attended all the eligibility criteria and were selected. China was the country with the highest frequency of Salmonella strains with the mcr gene, and Europe exhibited a wide diversity of countries with positive mcr strains. In addition, animals and humans carried the highest frequency of positive strains for the mcr gene. Salmonella Typhimurium was the most frequent serovar carrying the mcr gene. Apparently, colistin overuse in animal husbandry has increased the selective pressure of antimicrobial resistance, resulting in the emergence of a plasmid-mediated colistin resistance mcr gene in China. The mcr-positive Salmonella strains are recently predominant worldwide, which is probably due to the capacity of this gene to be swiftly horizontally transmissible. The transmission ability of mcr-positive Salmonella strains to humans through the consumption of contaminated animal-based food is a public health concern. 相似文献
905.
Pinto Samara Macedo Monteiro-Neto Cassiano Barbarino Elisabete de Almeida Tubino Rafael da Costa Marcus Rodrigues 《Ichthyological Research》2022,69(2):236-247
Ichthyological Research - The spatial and seasonal dynamics of shallow water fish assemblages and their relationship with physical-chemical variables were investigated on Guanabara Bay, one of the... 相似文献
906.
Nicholas J. Gotelli Faye Moyes Laura H. Anto Shane A. Blowes Maria Dornelas Brian J. McGill Amelia Penny Aafke M. Schipper Hideyasu Shimadzu Sarah R. Supp Conor A. Waldock Anne E. Magurran 《Global Change Biology》2022,28(1):46-53
The species composition of plant and animal assemblages across the globe has changed substantially over the past century. How do the dynamics of individual species cause this change? We classified species into seven unique categories of temporal dynamics based on the ordered sequence of presences and absences that each species contributes to an assemblage time series. We applied this framework to 14,434 species trajectories comprising 280 assemblages of temperate marine fishes surveyed annually for 20 or more years. Although 90% of the assemblages diverged in species composition from the baseline year, this compositional change was largely driven by only 8% of the species' trajectories. Quantifying the reorganization of assemblages based on species shared temporal dynamics should facilitate the task of monitoring and restoring biodiversity. We suggest ways in which our framework could provide informative measures of compositional change, as well as leverage future research on pattern and process in ecological systems. 相似文献
907.
908.
909.
Amaral Joo Henrique Fernandes Melack John Michael Barbosa Pedro Maia Borges Alberto V. Kasper Daniele Corts Alicia Cortes Zhou Wencai MacIntyre Sally Forsberg Bruce Rider 《Ecosystems》2022,25(4):911-930
Ecosystems - Extensive floodplains and numerous lakes in the Amazon basin are well suited to examine the role of floodable lands within the context of the sources and processing of carbon within... 相似文献
910.
Alfieri Fabio Botton-Divet Léo Nyakatura John A. Amson Eli 《Journal of Mammalian Evolution》2022,29(2):283-312
Journal of Mammalian Evolution - Identifying ecomorphological convergence examples is a central focus in evolutionary biology. In xenarthrans, slow arboreality independently arose at least three... 相似文献