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851.
Chris P. Verschoor Jennie Johnstone Jamie Millar Robin Parsons Alina Lelic Mark Loeb Jonathan L. Bramson Dawn M. E. Bowdish 《PloS one》2014,9(8)
Background
Circulating myeloid cells are important mediators of the inflammatory response, acting as a major source of resident tissue antigen presenting cells and serum cytokines. They represent a number of distinct subpopulations whose functional capacity and relative concentrations are known to change with age. Little is known of these changes in the very old and physically frail, a rapidly increasing proportion of the North American population.Design
In the following study the frequency and receptor expression of blood monocytes and dendritic cells (DCs) were characterized in a sample of advanced-age, frail elderly (81–100 yrs), and compared against that of adults (19–59 yrs), and community-dwelling seniors (61–76 yrs). Cytokine responses following TLR stimulation were also investigated, as well as associations between immunophenotyping parameters and chronic diseases.Results
The advanced-age, frail elderly had significantly fewer CD14(++) and CD14(+)CD16(+), but not CD14(++)CD16(+) monocytes, fewer plasmacytoid and myeloid DCs, and a lower frequency of monocytes expressing the chemokine receptors CCR2 and CX3CR1. At baseline and following stimulation with TLR-2 and -4 agonists, monocytes from the advanced-age, frail elderly produced more TNF than adults, although the overall induction was significantly lower. Finally, monocyte subset frequency and CX3CR1 expression was positively associated with dementia, while negatively associated with anemia and diabetes in the advanced-age, frail elderly.Conclusions
These data demonstrate that blood monocyte frequency and phenotype are altered in the advanced-age, frail elderly and that these changes correlate with certain chronic diseases. Whether these changes contribute to or are caused by these conditions warrants further investigation. 相似文献852.
Ma?gorzata Piotrowska Anna Otlewska Katarzyna Rajkowska Anna Koziróg Mariusz Hachu?ka Paulina Nowicka-Krawczyk Grzegorz J. Wolski Beata Gutarowska Alina Kunicka-Styczyńska Agnieszka ?ydzik-Bia?ek 《PloS one》2014,9(10)
The paper presents the results of a study conducted at the Auschwitz-Birkenau State Museum in Oświęcim on the occurrence of biodeterioration. Visual assessment of the buildings revealed signs of deterioration of the buildings in the form of dampness, bulging and crumbling plaster, and wood fiber splitting. The external surfaces, and especially the concrete strips and ground immediately adjoining the buildings, were colonized by bryophytes, lichens, and algae. These organisms developed most intensively close to the ground on the northern sides of the buildings. Inside the buildings, molds and bacteria were not found to develop actively, while algae and wood-decaying fungi occurred locally. The factors conducive to biological corrosion in the studied buildings were excessive dampness of structural partitions close to the ground and a relative air humidity of above 70%, which was connected to ineffective moisture insulation. The influence of temperature was smaller, as it mostly affected the quantitative composition of the microorganisms and the qualitative composition of the algae. Also the impact of light was not very strong, but it was conducive to algae growth. 相似文献
853.
Mei Ling Lim Brandon Nick Sern Ooi Philipp Jungebluth Sebastian Sj?qvist Isabell Hultman Greg Lemon Ylva Gustafsson Jurate Asmundsson Silvia Baiguera Iyadh Douagi Irina Gilevich Alina Popova Johannes Cornelius Haag Antonio Beltrán Rodríguez Jianri Lim Agne Liedén Magnus Nordenskj?ld Evren Alici Duncan Baker Christian Unger Tom Luedde Ivan Vassiliev Jose Inzunza Lars ?hrlund-Richter Paolo Macchiarini 《PloS one》2014,9(9)
Stem cells contribute to regeneration of tissues and organs. Cells with stem cell-like properties have been identified in tumors from a variety of origins, but to our knowledge there are yet no reports on tumor-related stem cells in the human upper respiratory tract. In the present study, we show that a tracheal mucoepidermoid tumor biopsy obtained from a 6 year-old patient contained a subpopulation of cells with morphology, clonogenicity and surface markers that overlapped with bone marrow mesenchymal stromal cells (BM-MSCs). These cells, designated as MEi (mesenchymal stem cell-like mucoepidermoid tumor) cells, could be differentiated towards mesenchymal lineages both with and without induction, and formed spheroids in vitro. The MEi cells shared several multipotent characteristics with BM-MSCs. However, they displayed differences to BM-MSCs in growth kinectics and gene expression profiles relating to cancer pathways and tube development. Despite this, the MEi cells did not possess in vivo tumor-initiating capacity, as proven by the absence of growth in situ after localized injection in immunocompromised mice. Our results provide an initial characterization of benign tracheal cancer-derived niche cells. We believe that this report could be of importance to further understand tracheal cancer initiation and progression as well as therapeutic development. 相似文献
854.
Anca Lădaru Paul Bălănescu Mihaela Stan Ioana Codreanu Ioana Alina Anca 《Biomarkers》2016,21(2):102-114
Context: Non-alcoholic fatty liver disease (NAFLD) is characterized by lipid accumulation in the liver which is accompanied by a series of metabolic deregulations. There are sustained research efforts focusing upon biomarker discovery for NAFLD diagnosis and its prognosis in order investigate and follow-up patients as minimally invasive as possible.Objective: The objective of this study is to critically review proteomic studies that used mass spectrometry techniques and summarize relevant proteomic NAFLD candidate biomarkers.Methods: Medline and Embase databases were searched from inception to December 2014.Results: A final number of 22 records were included that identified 251 candidate proteomic biomarkers. Thirty-three biomarkers were confirmed – 14 were found in liver samples, 21 in serum samples, and two from both serum and liver samples.Conclusion: Some of the biomarkers identified have already been extensively studied regarding their diagnostic and prognostic capacity. However, there are also more potential biomarkers that still need to be addressed in future studies. 相似文献
855.
Changes in different parameters,lymphocyte proliferation and hematopoietic progenitor colony formation in EAE mice treated with myelin oligodendrocyte glycoprotein 下载免费PDF全文
Vasilii B. Doronin Taisiya A. Parkhomenko Alexey Korablev Ludmila B. Toporkova Julia A. Lopatnikova Alina A. Alshevskaja Sergei V. Sennikov Valentina N. Buneva Thomas Budde Sven G. Meuth Irina A. Orlovskaya Nelly A. Popova Georgy A. Nevinsky 《Journal of cellular and molecular medicine》2016,20(1):81-94
Myelin oligodendrocyte glycoprotein (MOG) is an antigen of the myelin sheath, which may trigger immune cell responses and the production of auto‐antibodies in multiple sclerosis (MS). In this study, we used MOG35‐55‐induced experimental autoimmune encephalomyelitis (EAE), a model of human MS, to assess the production of catalytically active immunoglobulin G (IgG) antibodies or abzymes which have been shown to be present in sera of patients with several autoimmune diseases. Here, we show that IgGs from the sera of control C57BL/6 mice are catalytically inactive. During development of EAE, a specific reorganization of the immune system of mice occurred leading to a condition which was associated with the generation of catalytically active IgGs hydrolysing DNA, myelin basic protein (MBP) and MOG which was associated with increased proteinuria, changes in differentiation of mice bone marrow hematopoietic stem cells (HSCs) and an increase in proliferation of lymphocytes in bone marrow, spleen and thymus as well as a significant suppression of cell apoptosis in these organs. The strongest alterations were found in the early disease phase (18–24 days after immunization) and were less pronounced in later EAE stages (40 days after EAE induction). We conclude that a significant increase in DNase and proteolytic activities of antibodies may be considered the earliest statistically significant marker of MOG‐induced EAE in mice. The possible differences in immune system reorganizations during preclinical phases of the disease, acute and late EAE, leading to production of different auto‐antibodies and abzymes as well other changes are discussed. 相似文献
856.
All forms of domesticated tetraploid wheat (Triticum turgidum, genomes AABB) are nearly monomorphic for restriction fragment length polymorphism (RFLP) haplotype a at the Xpsr920 locus on chromosome 4A (Xpsr920-A1a), and wild tetraploid wheat is monomorphic for haplotype b. The Xpsr920-A1a/b dimorphism provides a molecular marker for domesticated and wild tetraploid wheat, respectively. Hexaploid wheat (Triticum aestivum, genomes AABBDD) is polymorphic for the 2 haplotypes. Bacterial artificial chromosome (BAC) clones hybridizing with PSR920 were isolated from Triticum urartu (genomes AA), Triticum monococcum (genomes AmAm), and T. turgidum ssp. durum (genomes AABB) and sequenced. PSR920 is a fragment of a putative ATP binding cassette (ABC) transporter gene (designated ABCT-1). The wheat ABCT-1 gene is more similar to the T. urartu gene than to the T. monococcum gene and diverged from the T. urartu gene about 0.7 MYA. The comparison of the sequence of the wheat A genome BAC clone with that of the T. urartu BAC clone provides the first insight into the microsynteny of the wheat A genome with that of T. urartu. Within 103 kb of orthologous intergenic space, 37 kb of new DNA has been inserted and 36 kb deleted leaving 49.7% of the region syntenic between the clones. The nucleotide substitution rate in the syntenic intergenic space has been 1.6 x 10(-8) nt(-1) year(-1), which is, respectively, 4 and 3 times as great as nucleotide substitution rates in the introns and the third codon positions of the juxtaposed gene. The RFLP is caused by a miniature inverted transposable element (MITE) insertion into intron 18 of the ABCT-A1 gene. Polymerase chain reaction primers were developed for the amplification of the MITE insertion site and its sequencing. The T. aestivum ABCT-A1a haplotype is identical to the haplotype of domesticated tetraploid wheat, and the ABCT-A1b haplotype is identical to that of wild tetraploid wheat. This finding shows for the first time that wild tetraploid wheat participated in the evolution of hexaploid wheat. A cline of the 2 haplotype frequencies exists across Euro-Asia in T. aestivum. It is suggested that T. aestivum in eastern Asia conserved the gene pool of the original T. aestivum more than wheat elsewhere. 相似文献
857.
Degraded reefs with a high abundance of macroalgae usually also have low densities of coral recruits. Few studies, however,
have examined whether these algae affect coral larval settlement. This study demonstrates, experimentally, that larvae of
the Caribbean coral Favia fragrum can settle on the green alga Halimeda opuntia even when another substrate more suitable for settlement is present. Larval settlement onto experimental substrates was quantified
under three treatments: rubble only, rubble plus plastic algal mimic, and rubble plus live H. opuntia. Similar total larval settlement was observed in all treatments. No larvae settled on the algal mimic, but total settlement
was similar on the rubble in the first two treatments, showing that the rubble alone offered sufficient substrate for high
settlement success. About half the larvae in the live algal treatment settled on H. opuntia instead of on the rubble, showing that larvae did not reject this substrate as they did the algal mimic. This result raises
the possibility that corals will settle on some macroalgae when their abundance is high. Most macroalgae, including H. opuntia, are ephemeral substrates unsuitable for post-settlement survival. Such unexpected settlement may therefore have significant
consequences for coral recruitment success on algal-dominated reefs. 相似文献
858.
Elisa Quiala Raul Barbón Elio Jimenez Manuel De Feria Maité Chávez Alina Capote Naivy Pérez 《In vitro cellular & developmental biology. Plant》2006,42(3):298-300
Summary
In vitro plants of lemon grass were established, starting from shoot apices derived from plants cultivated under field conditions.
The effect of the immersion frequency (two, four, and six immersions per day) on the production of biomass in temporary immersion
systems (TIS) of 1 liter capacity was studied. The highest multiplication coefficient (12.3) was obtained when six immersions
per day were used. The maximum values of fresh weight (FW; 62.2 and 66.2 g) were obtained with a frequency of four and six
immersions per day, respectively. However, the values for dry weight (DW; 6.4g) and height (8.97cm) were greater in the treatment
with four immersions per day. The TIS used in this work for the production of lemon grass biomass may offer the possibility
of manipulating the culture parameters, which can influence the production of biomass and the accumulation of secondary metabolites.
We describe for the first time the in vitro production of Cymbopogon citratus biomass in TIS. 相似文献
859.
Kirill A. Kondratov Alexander L. Chernorudskiy Alina P. Amosova Elena S. Kornilova 《Cell biology international》2010,34(1):81-87
Tyrphostin AG1478 is known as a specific and reversible inhibitor of TK (tyrosine kinase) activity of the EGFR [EGF (epidermal growth factor) receptor]. It is attractive as an anticancer agent for cancers with elevated EGFR TK levels. However, post‐application effects of AG1478 are not well studied. We have analysed EGFR phosphorylation after termination of AG1478 application using human epidermoid carcinoma A431 cells. It was found that AG1478 inhibitory action is fast, but not fully reversible: removal of tyrphostin resulted in incomplete restoration of the overall EGFR phosphorylation. Analysing the state of two individual autophosphorylation sites of internalized EGFR, Tyr1045 and Tyr1173, we demonstrated that phosphorylation of Tyr1173 involved in stimulation of the MAPK (mitogen‐activated protein kinase) cascade was restored much more efficiently than that in position 1045, which binds the ubiquitin ligase c‐Cbl and is necessary for targeting the receptor for lysosomal degradation. c‐Cbl association with EGFR abolished by AG1478 was not reestablished after tyrphostin cessation. As a consequence, ubiquitination‐dependent EGFR delivery to lysosomes was blocked, while phosphorylation of ERK1/2 (extracellular‐signal‐regulated kinase 1/2) was even increased. Thus, after termination of AG1478, the intracellular level of the inhibitor can be reached at which mitogenic signalling will be restored, whereas the EGFR negative regulation due to lysosomal degradation will not. 相似文献
860.
Virus recognition and induction of interferon (IFN) are critical components of the innate immune system. The Toll-like receptor
(TLR) and RIG-I-like receptor families have been characterized as key players in RNA virus detection. Signaling cascades initiated
by these receptors are crucial for establishment of an IFN signaling mediated antiviral state in infected and neighboring
cells and containment of virus replication as well as initiation of the adaptive immune response. In this review, we focus
on the diverse and overlapping functions of these receptors, their physiological importance, and respective viral inducers.
We highlight the roles of TRL3, TLR7/8, retinoic acid inducible gene I, melanoma differentiation-associated gene 5, and the
RNA molecules responsible for activating these viral sensors. 相似文献