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21.
E Enowashu E Kandeler M Schloter F Rasche M Engel 《Journal of microbiological methods》2012,91(1):14-21
A new set of primers was developed allowing the specific detection of the pepN gene (coding for alanine aminopeptidase) from Gram-negative bacteria. The primers were designed in silico by sequence alignments based on available DNA sequence data. The PCR assay was validated using DNA from selected pure cultures. The analysis of gene libraries from extracted DNA from different soil samples revealed a high diversity of pepN related sequences mainly related to α-Proteobacteria. Most sequences obtained from clone libraries were closely related to already published sequences (<80% homology on amino acid level), which may be related to the conserved character of the amplified region of pepN. By linking the diversity data obtained by the clone library studies to potential enzymatic activities of alanine aminopeptidase, lowest diversity of pepN was found in those soil samples which displayed lowest activity levels, which confirms the importance of diversity for the ecosystem function mainly when transformation processes of complex molecules are studied. 相似文献
22.
Richardson RT Alekseev OM Grossman G Widgren EE Thresher R Wagner EJ Sullivan KD Marzluff WF O'Rand MG 《The Journal of biological chemistry》2006,281(30):21526-21534
A multichaperone nucleosome-remodeling complex that contains the H1 linker histone chaperone nuclear autoantigenic sperm protein (NASP) has recently been described. Linker histones (H1) are required for the proper completion of normal development, and NASP transports H1 histones into nuclei and exchanges H1 histones with DNA. Consequently, we investigated whether NASP is required for normal cell cycle progression and development. We now report that without sufficient NASP, HeLa cells and U2OS cells are unable to replicate their DNA and progress through the cell cycle and that the NASP(-/-) null mutation causes embryonic lethality. Although the null mutation NASP(-/-) caused embryonic lethality, null embryos survive until the blastocyst stage, which may be explained by the presence of stored NASP protein in the cytoplasm of oocytes. We conclude from this study that NASP and therefore the linker histones are key players in the assembly of chromatin after DNA replication. 相似文献
23.
Pura Díaz-Veiga Mayte Sancho Álvaro García Esther Rivas Elixabet Abad Nerea Suárez Gabriela Mondragón Cristina Buiza Ana Orbegozo Javier Yanguas 《Revista espa?ola de geriatría y gerontología》2014
Introduction
The Model of Person Centered Care has attracted increasing interest for use in gerontology centers. Therefore, the contributions about its impact are scarce in our context. The objective of this paper is to establish the impact that the interventions associated with the Model of Person Centered Care in the «Etxean Ondo» Project have on the quality of life of residents with cognitive impairment.Material and methods
One hundred and ninetten residents with cognitive impairment were selected: 59 in the control group and 60 in the experimental group. Subjects in each group were sorted by cognitive impairment: mild or severe. Changes were implemented in the physical and organizational environments for the promotion of autonomy and wellbeing. Quality of life was assessed before and 6 months after intervention using the Fumat Scales (mild cognitive impairment) and Qualid (severe cognitive impairment). The t-Student test was used for comparison of means.Results
In intergroup comparisons, significant differences in the Fumat Scale for the control group with mild cognitive impairment were initially identified. These differences were not recorded in the post assessment. The experimental group with severe cognitive impairment was significantly improved in the Qualid Scale post assessment. In intragroup comparisons, significant improvements were evident in the quality of life of experimental subjects, both with severe cognitive impairment (Qualid) and mild (Fumat).Conclusions
The findings support the effectiveness of the interventions and identify methodological and conceptual issues that have been considered to analyze the Model of Person Centered Care efects. 相似文献24.
Emily E. I. M. Mouser Georgios Pollakis Maria Yazdanbakhsh William Harnett Esther C. de Jong William A. Paxton 《PloS one》2016,11(1)
One of the hallmarks of HIV-1 disease is the association of heightened CD4+ T-cell activation with HIV-1 replication. Parasitic helminths including filarial nematodes have evolved numerous and complex mechanisms to skew, dampen and evade human immune responses suggesting that HIV-1 infection may be modulated in co-infected individuals. Here we studied the effects of two filarial nematode products, adult worm antigen from Brugia malayi (BmA) and excretory-secretory product 62 (ES-62) from Acanthocheilonema viteae on HIV-1 infection in vitro. Neither BmA nor ES-62 influenced HIV-1 replication in CD4+ enriched T-cells, with either a CCR5- or CXCR4-using virus. BmA, but not ES-62, had the capacity to bind the C-type lectin dendritic cell-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN) thereby inhibiting HIV-1 trans-infection of CD4+ enriched T-cells. As for their effect on DCs, neither BmA nor ES-62 could enhance or inhibit DC maturation as determined by CD83, CD86 and HLA-DR expression, or the production of IL-6, IL-10, IL-12 and TNF-α. As expected, due to the unaltered DC phenotype, no differences were found in CD4+ T helper (Th) cell phenotypes induced by DCs treated with either BmA or ES-62. Moreover, the HIV-1 susceptibility of the Th-cell populations induced by BmA or ES-62 exposed DCs was unaffected for both CCR5- and CXCR4-using HIV-1 viruses. In conclusion, although BmA has the potential capacity to interfere with HIV-1 transmission or initial viral dissemination through preventing the virus from interacting with DCs, no differences in the Th-cell polarizing capacity of DCs exposed to BmA or ES-62 were observed. Neither antigenic source demonstrated beneficial or detrimental effects on the HIV-1 susceptibility of CD4+ Th-cells induced by exposed DCs. 相似文献
25.
26.
Claudia Siegl Patricia Hamminger Herbert Jank Uwe Ahting Benedikt Bader Adrian Danek Allison Gregory Monika Hartig Susan Hayflick Andreas Hermann Holger Prokisch Esther M. Sammler Zuhal Yapici Rainer Prohaska Ulrich Salzer 《PloS one》2013,8(10)
Neuroacanthocytosis (NA) refers to a group of heterogenous, rare genetic disorders, namely chorea acanthocytosis (ChAc), McLeod syndrome (MLS), Huntington’s disease-like 2 (HDL2) and pantothenate kinase associated neurodegeneration (PKAN), that mainly affect the basal ganglia and are associated with similar neurological symptoms. PKAN is also assigned to a group of rare neurodegenerative diseases, known as NBIA (neurodegeneration with brain iron accumulation), associated with iron accumulation in the basal ganglia and progressive movement disorder. Acanthocytosis, the occurrence of misshaped erythrocytes with thorny protrusions, is frequently observed in ChAc and MLS patients but less prevalent in PKAN (about 10%) and HDL2 patients. The pathological factors that lead to the formation of the acanthocytic red blood cell shape are currently unknown. The aim of this study was to determine whether NA/NBIA acanthocytes differ in their functionality from normal erythrocytes. Several flow-cytometry-based assays were applied to test the physiological responses of the plasma membrane, namely drug-induced endocytosis, phosphatidylserine exposure and calcium uptake upon treatment with lysophosphatidic acid. ChAc red cell samples clearly showed a reduced response in drug-induced endovesiculation, lysophosphatidic acid-induced phosphatidylserine exposure, and calcium uptake. Impaired responses were also observed in acanthocyte-positive NBIA (PKAN) red cells but not in patient cells without shape abnormalities. These data suggest an “acanthocytic state” of the red cell where alterations in functional and interdependent membrane properties arise together with an acanthocytic cell shape. Further elucidation of the aberrant molecular mechanisms that cause this acanthocytic state may possibly help to evaluate the pathological pathways leading to neurodegeneration. 相似文献
27.
Jose Itzigsohn Carlos Dore Cabral Esther Hernandez Medina Obed Vazquez 《Ethnic and racial studies》2013,36(2):316-339
This article maps the structure for understanding the Dominican transnational field. By transnational field we refer to a web of linkages that affects the lives of Dominicans in their places of residence in every social field. We find that social boundaries of the nation do not coincide with political ones and the degree of participation in transnational exchanges varies. We suggest that the structure of the transnational social field is better understood by establishing and defining broad and narrow transnational social practices. 相似文献
28.
Samantha A. Spangler Sabine K. Schmitz Josta T. Kevenaar Esther de Graaff Heidi de Wit Jeroen Demmers Ruud F. Toonen Casper C. Hoogenraad 《The Journal of cell biology》2013,201(6):915-928
The presynaptic active zone mediates synaptic vesicle exocytosis, and modulation of its molecular composition is important for many types of synaptic plasticity. Here, we identify synaptic scaffold protein liprin-α2 as a key organizer in this process. We show that liprin-α2 levels were regulated by synaptic activity and the ubiquitin–proteasome system. Furthermore, liprin-α2 organized presynaptic ultrastructure and controlled synaptic output by regulating synaptic vesicle pool size. The presence of liprin-α2 at presynaptic sites did not depend on other active zone scaffolding proteins but was critical for recruitment of several components of the release machinery, including RIM1 and CASK. Fluorescence recovery after photobleaching showed that depletion of liprin-α2 resulted in reduced turnover of RIM1 and CASK at presynaptic terminals, suggesting that liprin-α2 promotes dynamic scaffolding for molecular complexes that facilitate synaptic vesicle release. Therefore, liprin-α2 plays an important role in maintaining active zone dynamics to modulate synaptic efficacy in response to changes in network activity. 相似文献
29.
Rendal Vázquez ME Díaz Román TM Rodríguez Cabarcos M Zavanella Botta C Domenech García N González Cuesta M Sánchez Dopico MJ Pértega Díaz S Andión Núñez C 《Cell and tissue banking》2008,9(2):101-107
To analyse the influence of cold ischemic time (CIT) (2–24 h) and of cryopreservation (liquid phase) on the viability of the
valvular fibroblasts and in the presence of apoptosis. Cardiac valves from 10 pigs were evaluated by anatomo-pathological
study of the wall, muscle and leaflet. At the same time, the presence of cellular death due to apoptosis was investigated
in two ways; directly on tissue by Apodetec system and by two-colour flow cytometry assay analyzing a suspension of fibroblast
from valve leaflets using Anexina V and propidium iodure (PI). We established three groups of samples to compare different
experimental conditions: 2 h of ischemia (group 1), 24 h of ischemia (group 2), and a programme of cryopreservation (−1°C/min)
after 2 h of ischemia, followed by storage in liquid nitrogen during a week and thawing was performed (group 3). The analysis
of viabilities showed slight differences between all three groups. The results indicated CIT of 24 h undergoing more structural
affectation than CIT of 2 h. Flow cytometry analysis did not show important differences between groups; however cryopreserved
samples (group 3) slightly less viability and a higher percentage of death by apoptosis than group 1 and 2 using flow cytometry.
Apoptosis was confirmed on tissue from all valves but mainly in samples of group 2 and group 3. In summary, the viability
of the valves in the case of ischemic times of 2 h, 24 h or after cryopreservation/thawing differs slightly. The death of
the cells is mainly mediated by necrosis and not by apoptosis. 相似文献
30.