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101.
Phagocytosis plays a central role in immunity and tissue homeostasis. After internalization of cargo into single-membrane phagosomes, these compartments undergo a maturation sequences that terminates in lysosome fusion and cargo degradation. Components of the autophagy pathway have recently been linked to phagosome maturation in a process called LC3-associated phagocytosis (LAP). In this process, autophagy machinery is thought to conjugate LC3 directly onto the phagosomal membrane to promote lysosome fusion. However, a recent study has suggested that ATG proteins may in fact impair phagosome maturation to promote antigen presentation. Here, we examined the impact of ATG proteins on phagosome maturation in murine cells using FCGR2A/FcγR-dependent phagocytosis as a model. We show that phagosome maturation is not affected in Atg5-deficient mouse embryonic fibroblasts, or in Atg5- or Atg7-deficient bone marrow-derived macrophages using standard assays of phagosome maturation. We propose that ATG proteins may be required for phagosome maturation under some conditions, but are not universally required for this process. 相似文献
102.
Christine Ewers‐Saucedo James M. Pringle Hector H. Sepúlveda James E. Byers Sergio A. Navarrete John P. Wares 《Ecology and evolution》2016,6(13):4403-4420
Dispersal and adaptation are the two primary mechanisms that set the range distributions for a population or species. As such, understanding how these mechanisms interact in marine organisms in particular – with capacity for long‐range dispersal and a poor understanding of what selective environments species are responding to – can provide useful insights for the exploration of biogeographic patterns. Previously, the barnacle Notochthamalus scabrosus has revealed two evolutionarily distinct lineages with a joint distribution that suggests an association with one of the two major biogeographic boundaries (~30°S) along the coast of Chile. However, spatial and genomic sampling of this system has been limited until now. We hypothesized that given the strong oceanographic and environmental shifts associated with the other major biogeographic boundary (~42°S) for Chilean coastal invertebrates, the southern mitochondrial lineage would dominate or go to fixation in locations further to the south. We also evaluated nuclear polymorphism data from 130 single nucleotide polymorphisms to evaluate the concordance of the signal from the nuclear genome with that of the mitochondrial sample. Through the application of standard population genetic approaches along with a Lagrangian ocean connectivity model, we describe the codistribution of these lineages through a simultaneous evaluation of coastal lineage frequencies, an approximation of larval behavior, and current‐driven dispersal. Our results show that this pattern could not persist without the two lineages having distinct environmental optima. We suggest that a more thorough integration of larval dynamics, explicit dispersal models, and near‐shore environmental analysis can explain much of the coastal biogeography of Chile. 相似文献
103.
ángela María Sánchez-López Abdellatif Bahaji Nuria De Diego Marouane Baslam Jun Li Francisco José Mu?oz Goizeder Almagro Pablo García-Gómez Kinia Ameztoy Adriana Ricarte-Bermejo Ond?ej Novák Jan F. Humplík Luká? Spíchal Karel Dole?al Sergio Ciordia María Carmen Mena Rosana Navajas Edurne Baroja-Fernández Javier Pozueta-Romero 《Plant physiology》2016,172(3):1989-2001
104.
105.
Erinaldo Ubirajara Damasceno dos Santos Géssica Dayane Cordeiro de Lima Micheline de Lucena Oliveira Sandra de Andrade Heráclio Hildson Dornelas Angelo da Silva Sergio Crovella Maria de Mascena Diniz Maia Paulo Roberto Eleutério de Souza/ 《Memórias do Instituto Oswaldo Cruz》2016,111(3):174-180
Polymorphisms in chemokine receptors play an important role in the progression of
cervical intraepithelial neoplasia (CIN) to cervical cancer (CC). Our study examined
the association of CCR2-64I (rs1799864) andCCR5-Δ32
(rs333) polymorphisms with susceptibility to develop cervical lesion (CIN and CC) in
a Brazilian population. The genotyping of 139 women with cervical lesions and 151
women without cervical lesions for the CCR2-64I and
CCR5-Δ32 polymorphisms were performed using polymerase chain
reaction-restriction fragment length polymorphism. The individuals carrying
heterozygous or homozygous genotypes (GA+AA) for CCR2-64I
polymorphisms seem to be at lower risk for cervical lesion [odds ratio (OR) = 0.37, p
= 0.0008)]. The same was observed for the A allele (OR = 0.39, p = 0.0002), while no
association was detected (p > 0.05) with CCR5-Δ32 polymorphism.
Regarding the human papillomavirus (HPV) type, patients carrying the
CCR2-64Ipolymorphism were protected against infection by HPV type
16 (OR = 0.35, p = 0.0184). In summary, our study showed a protective effect
ofCCR2-64I rs1799864 polymorphism against the development of
cervical lesions (CIN and CC) and in the susceptibility of HPV 16 infection. 相似文献
106.
García-Pérez Teresa Le Borgne Sylvie Revah Sergio 《Applied microbiology and biotechnology》2016,100(24):10637-10647
Applied Microbiology and Biotechnology - The operation and performance of a biotrickling filter for methanol (MeOH) and hydrogen sulfide (H2S) removal at acid pH was studied. Excess biomass in the... 相似文献
107.
Anna?Aiello Giulia?Accardi Giuseppina?Candore Giuseppe?Carruba Sergio?Davinelli Giuseppe?Passarino Giovanni?Scapagnini Sonya?Vasto Calogero?CarusoEmail author 《Immunity & ageing : I & A》2016,13(1):17
During the last two centuries the average lifespan has increased at a rate of approximately 3 months/year in both sexes, hence oldest old people are becoming the population with the fastest growth in Western World. Although the average life expectancy is increasing dramatically, the healthy lifespan is not going at the same pace. This underscores the importance of studies on the prevention of age-related diseases, in order to satisfactorily decrease the medical, economic and social problems associated to advancing age, related to an increased number of individuals not autonomous and affected by invalidating pathologies. In particular, data from experimental studies in model organisms have consistently shown that nutrient signalling pathways are involved in longevity, affecting the prevalence of age-related loss of function, including age-related diseases. Accordingly, nutrigerontology is defined as the scientific discipline that studies the impact of nutrients, foods, macronutrient ratios, and diets on lifespan, ageing process, and age-related diseases. To discuss the potential relevance of this new science in the attainment of successful ageing and longevity, three original studies performed in Sicily with local foods and two reviews have been assembled in this series. Data clearly demonstrate the positive effects of nutraceuticals, functional foods and Mediterranean Diet on several biological parameters. In fact, they could represent a prevention for many age-related diseases, and, although not a solution for this social plague, at least a remedy to alleviate it. Thus, the possibility to create a dietary pattern, based on the combined strategy of the use of both nutraceuticals and functional foods should permit to create a new therapeutic strategy, based not only on a specific bioactive molecule or on a specific food but on a integrated approach that, starting from the local dietary habits, can be led to a “nutrafunctional diet” applicable worldwide. 相似文献
108.
Marie-Pierre Piccinni Letizia Lombardelli Federica Logiodice Ornela Kullolli Paola Parronchi Sergio Romagnani 《Clinical and molecular allergy : CMA》2016,14(1):11
Autoimmune disorders are characterized by tissue damage, caused by self-reactivity of different effectors mechanisms of the immune system, namely antibodies and T cells. Their occurrence may be associated with genetic and/or environmental predisposition and to some extent, have implications for fertility and obstetrics. The relationship between autoimmunity and reproduction is bidirectional. This review only addresses the impact of pregnancy on autoimmune diseases and not the influence of autoimmunity on pregnancy development. Th17/Th1-type cells are aggressive and pathogenic in many autoimmune disorders and inflammatory diseases. The immunology of pregnancy underlies the role of Th2-type cytokines to maintain the tolerance of the mother towards the fetal semi-allograft. Non-specific factors, including hormonal changes, favor a switch to Th2-type cytokine profile. In pregnancy Th2, Th17/Th2 and Treg cells accumulate in the decidua but may also be present in the mother’s circulation and can regulate autoimmune responses influencing the progression of autoimmune diseases. 相似文献
109.
Jasminka Boskovic Elisabeth Bragado-Nilsson Bhargrav Saligram Prabhakar Igor Yefimenko Jaime Martínez-Gago Sergio Muñoz 《Cell cycle (Georgetown, Tex.)》2016,15(18):2431-2440
DNA replication is a key biological process that involves different protein complexes whose assembly is rigorously regulated in a successive order. One of these complexes is a replicative hexameric helicase, the MCM complex, which is essential for the initiation and elongation phases of replication. After the assembly of a double heterohexameric MCM2-7 complex at replication origins in G1, the 2 heterohexamers separate from each other and associate with Cdc45 and GINS proteins in a CMG complex that is capable of unwinding dsDNA during S phase. Here, we have reconstituted and characterized the purified human MCM2-7 (hMCM2-7) hexameric complex by co-expression of its 6 different subunits in insect cells. The conformational variability of the complex has been analyzed by single particle electron microscopy in the presence of different nucleotide analogs and DNA. The interaction with nucleotide stabilizes the complex while DNA introduces conformational changes in the hexamer inducing a cylindrical shape. Our studies suggest that the assembly of GINS and Cdc45 to the hMCM2-7 hexamer would favor conformational changes on the hexamer bound to ssDNA shifting the cylindrical shape of the complex into a right-handed spiral conformation as observed in the CMG complex bound to DNA. 相似文献
110.
Sergio Serrano-Villar Talia Sainz Zhong-Min Ma Netanya S. Utay Tae-Wook Chun Surinder Mann Angela D. Kashuba Basile Siewe Anthony Albanese Paolo Troia-Cancio Elizabeth Sinclair Anoma Somasunderam Tammy Yotter Steven G. Deeks Alan Landay Richard B. Pollard Christopher J. Miller Santiago Moreno David M. Asmuth 《PLoS pathogens》2016,12(3)