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171.
Apoptosis is a major problem in animal cell culture during production of biopharmaceuticals, such as recombinant proteins
or viral particles. In the present work baculovirus-insect cell expression system (BEVS/IC) is used as model to produce rotavirus
like-particles, composed by three layers of three different viral proteins (VP2, VP6 and VP7). In this model baculovirus infection
also induces host cell death. Herein a new strategy to enhance cell life span and to increase recombinant rotavirus protein
production of BEVS/IC system was developed. This strategy relies on hemolymph from Lonomia oblique (total extracts or a semi-purified fraction) medium supplementation. The total extract and a purified fraction from hemolymph
of Lonomia obliqua were able to protect Sf-9 cell culture against apoptosis triggered by oxidative stress (using the pro-oxidant agents tert butylhydroperoxide and hydrogen peroxide) and by baculovirus infection. Furthermore, hemolymph enhance final recombinant
protein production, as it was observed by the increased amounts of VP6 and VP7, which were measured by the semi-quantitative
western blot method. In conclusion, hemolymph medium supplementation can be a promising strategy to improve cell viability
and productivity of recombinant protein in BEVS/IC system. 相似文献
172.
Costa VM Torres KC Mendonça RZ Gresser I Gollob KJ Abrahamsohn IA 《Journal of immunology (Baltimore, Md. : 1950)》2006,177(5):3193-3200
The participation of type I IFNs (IFN-I) in NO production and resistance to Trypanosoma cruzi infection was investigated. Adherent cells obtained from the peritoneal cavity of mice infected by the i.p. route produced NO and IFN-I. Synthesis of NO by these cells was partially inhibited by treatment with anti-IFN-alphabeta or anti-TNF-alpha Abs. Compared with susceptible BALB/c mice, peritoneal cells from parasite-infected resistant C57BL/6 mice produced more NO (2-fold), IFN-I (10-fold), and TNF-alpha (3.5-fold). Later in the infection, IFN-I levels measured in spleen cell (SC) cultures from 8-day infected mice were greater in C57BL/6 than in infected BALB/c mice, and treatment of the cultures with anti-IFN-alphabeta Ab reduced NO production. IFN-gamma or IL-10 production by SCs was not different between the two mouse strains; IL-4 was not detectable. Treatment of C57BL/6 mice with IFN-I reduced parasitemia levels in the acute phase of infection. Mice deprived of the IFN-alphabetaR gene developed 3-fold higher parasitemia levels in the acute phase in comparison with control 129Sv mice. Production of NO by peritoneal macrophages and SCs was reduced in mice that lacked signaling by IFN-alphabeta, whereas parasitism of macrophages was heavier than in control wild-type mice. We conclude that IFN-I costimulate NO synthesis early in T. cruzi infection, which contributes to a better control of the parasitemia in resistant mice. 相似文献
173.
Phylogenetic relationships of butterflies of the tribe Acraeini (Lepidoptera, Nymphalidae, Heliconiinae) and the evolution of host plant use 总被引:1,自引:0,他引:1
Silva-Brandão KL Wahlberg N Francini RB Azeredo-Espin AM Brown KS Paluch M Lees DC Freitas AV 《Molecular phylogenetics and evolution》2008,46(2):515-531
The tribe Acraeini (Nymphalidae, Heliconiinae) is believed to comprise between one and seven genera, with the greatest diversity in Africa. The genera Abananote, Altinote, and Actinote (s. str.) are distributed in the Neotropics, while the genera Acraea, Bematistes, Miyana, and Pardopsis have a Palaeotropical distribution. The monotypic Pardopsis use herbaceous plants of the family Violaceae, Acraea and Bematistes feed selectively on plants with cyanoglycosides belonging to many plant families, but preferentially to Passifloraceae, and all Neotropical species with a known life cycle feed on Asteraceae only. Here, a molecular phylogeny is proposed for the butterflies of the tribe Acraeini based on sequences of COI, EF-1alpha and wgl. Both Maximum Parsimony and Bayesian analyses showed that the tribe is monophyletic, once the genus Pardopsis is excluded, since it appears to be related to Argynnini. The existing genus Acraea is a paraphyletic group with regard to the South American genera, and the species of Acraea belonging to the group of "Old World Actinote" is the sister group of the Neotropical genera. The monophyly of South American clade is strongly supported, suggesting a single colonization event of South America. The New World Actinote (s. str.) is monophyletic, and sister to Abananote+Altinote (polyphyletic). Based on the present results it was possible to propose a scenario for the evolution in host plant use within Acraeini, mainly concerning the use of Asteraceae by the South American genera. 相似文献
174.
Ilarri Martina I. Monteiro Rosana G. Ozório Rodrigo Sousa Ronaldo 《Hydrobiologia》2022,849(3):763-780
Hydrobiologia - Corbicula fluminea is a known aquatic invasive species responsible for several ecological and economic impacts. In Portugal, it is found in all major watersheds, although to varying... 相似文献
175.
Capitani Leonardo de Araujo Jlio Neves Vieira Edson A. Angelini Ronaldo Longo Guilherme O. 《Ecosystems》2022,25(4):843-857
Ecosystems - Ocean warming is altering life on Earth from individuals to ecosystems. The impacts on standing biomass and food webs functioning are less evident due to the paucity of data and... 相似文献
176.
Laurie Laugier Ludmila Rodrigues Pinto Ferreira Frederico Moraes Ferreira Sandrine Cabantous Amanda Farage Frade Joao Paulo Nunes Rafael Almeida Ribeiro Pauline Brochet Priscila Camillo Teixeira Ronaldo Honorato Barros Santos Edimar A. Bocchi Fernando Bacal Darlan da Silva Cndido Vanessa Escolano Maso Helder I. Nakaya Jorge Kalil Edecio Cunha-Neto Christophe Chevillard 《PLoS neglected tropical diseases》2020,14(12)
Chronic Chagas disease cardiomyopathy (CCC), an especially aggressive inflammatory dilated cardiomyopathy caused by lifelong infection with the protozoan Trypanosoma cruzi, is a major cause of cardiomyopathy in Latin America. Although chronic myocarditis may play a major pathogenetic role, little is known about the molecular mechanisms responsible for its severity. The aim of this study is to study the genes and microRNAs expression in tissues and their connections in regards to the pathobiological processes. To do so, we integrated for the first time global microRNA and mRNA expression profiling from myocardial tissue of CCC patients employing pathways and network analyses. We observed an enrichment in biological processes and pathways associated with the immune response and metabolism. IFNγ, TNF and NFkB were the top upstream regulators. The intersections between differentially expressed microRNAs and differentially expressed target mRNAs showed an enrichment in biological processes such as Inflammation, inflammation, Th1/IFN-γ-inducible genes, fibrosis, hypertrophy, and mitochondrial/oxidative stress/antioxidant response. MicroRNAs also played a role in the regulation of gene expression involved in the key cardiomyopathy-related processes fibrosis, hypertrophy, myocarditis and arrhythmia. Significantly, a discrete number of differentially expressed microRNAs targeted a high number of differentially expressed mRNAs (>20) in multiple processes. Our results suggest that miRNAs orchestrate expression of multiple genes in the major pathophysiological processes in CCC heart tissue. This may have a bearing on pathogenesis, biomarkers and therapy. 相似文献
177.
Carla Andreia Abreu Leandro Coelho Teixeira-Pinheiro Rafael Lani-Louzada Almir Jordão da Silva-Junior Juliana F. Vasques Fernanda Gubert Gabriel Nascimento-dos-Santos Ronaldo Mohana-Borges Eduardo de Souza Matos Pedro Moreno Pimentel-Coelho Marcelo Felippe Santiago Rosalia Mendez-Otero 《Journal of neurochemistry》2021,158(3):694-709
178.
Casearia souzae R.Marquete & Mansano,sp.nov.
(S4-1.Fig.1)
Type:Brazil.Espírito Santo:(A)guia Branca,Comunidade S(a)o Pedro,propriedade Sr.Jo(a)o Ferreira,Pedra da Bandeira,2008-01-17,M.C.Souza,M.M.Saavedra,R.F.Monteiro & C.N.Fraga 610 (holotype,RB;isotypes,IAC,IBGE,SPF). 相似文献
179.
David Silva Ronaldo Gabriel Maria Moreira João Abrantes Aurélio Faria 《Somatosensory & motor research》2013,30(3-4):170-177
AbstractObjective: This study aimed to investigate the foot contact time differences between obese and non-obese subjects during walking when crossing obstacles.Methods: Ninety-eight postmenopausal women were assigned to four groups, and their plantar pressure temporal data were collected using a two-step protocol during walking when crossing an obstacle set at 30% height of lower limb length of each subject. The initial, final, and duration of contact of 10?foot areas were measured.Results: Leading limb: (1) the heel groups initiated foot contact using the heel, and the non-heel groups initiated contact using the metatarsals; (2) heel obese subjects showed an earlier initial contact and a longer contact duration of metatarsals 2–3; (3) non-heel obese subjects showed an earlier midfoot initial contact. Regarding the trailing limb: (4) heel obese subjects showed an earlier midfoot initial contact and a longer contact duration of metatarsal 5; (5) non-heel obese subjects showed an earlier initial contact and a longer contact duration of metatarsals 4–5.Conclusions: (1) The non-heel groups’ foot rollover pattern may result from an attempt of rapidly restoring stability; (2) the heel obese subjects seem to regulate their plantar foot muscles to overcome their overweight; (3) the overweight of the non-heel obese subjects leads to a quicker backward foot roll-over from the metatarsals to the heel; (4) the overweight of the heel obese subjects can distort their footprints and/or their higher inertia may precipitate an anticipation of the midfoot contact, which can also explain the result observed for 5. 相似文献
180.