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991.
992.
Elżbieta Boratyn Iwona Nowak Elżbieta Karnas Damian Ryszawy Dawid Wnuk Anna Polus Małgorzata Durbas Irena Horwacik Hanna Rokita 《Journal of cellular biochemistry》2020,121(5-6):3406-3425
Monocyte chemoattractant protein-1-induced protein 1 (MCPIP1) has a multidomain structure, which assures its pleiotropic activity. The physiological functions of this protein include repression of inflammatory processes and the prevention of immune disorders. The influence of MCPIP1 on the cell cycle of cancer cells has not been sufficiently elucidated. A previous study by our group reported that overexpression of MCPIP1 affects the cell viability, inhibits the activation of the phosphoinositide-3 kinase/mammalian target of rapamycin signalling pathway, and reduces the stability of the MYCN oncogene in neuroblastoma (NB) cells. Furthermore, a decrease in expression and phosphorylation levels of cyclin-dependent kinase (CDK) 1, which has a key role in the M phase of the cell cycle, was observed. On the basis of these previous results, the purpose of our present study was to elucidate the influence of MCPIP1 on the cell cycle of NB cells. It was confirmed that ectopic overexpression of MCPIP1 in two human NB cell lines, KELLY and BE(2)-C, inhibited cell proliferation. Furthermore, flow cytometric analyses and imaging of the cell cycle with a fluorescence ubiquitination cell-cycle indicator test, demonstrated that overexpression of MCPIP1 causes an accumulation of NB cells in the G1 phase of the cell cycle, while the possibility of an increase in G0 phase due to induction of quiescence or senescence was excluded. Additional assessment of the molecular machinery responsible for the transition between the cell-cycle phases confirmed that MCPIP1 overexpression reduced the expression of cyclins A2, B1, D1, D3, E1, and E2 and decreased the phosphorylation of CDK2 and CDK4, as well as retinoblastoma protein. In conclusion, the present results indicated a relevant impact of overexpression of MCPIP1 on the cell cycle, namely a block of the G1/S cell-cycle checkpoint, resulting in arrest of NB cells in the G1 phase. 相似文献
993.
Meligy Fatma Y. Elgamal Dalia A. Abd Allah Eman S. H. Idriss Naglaa K. Ghandour Nagwa M. Bayoumy Ehab M. R. Khalil Azza Sayed Abdelrehim El Fiky Mohamed M. Elkhashab Mostafa 《Molecular biology reports》2019,46(6):5841-5858
Molecular Biology Reports - Parkinson’s disease (PD) is a chronic neurodegenerative disease. Unfortunately, the effectiveness of anti-Parkinson treatments gradually diminishes owing to the... 相似文献
994.
Fernanda P. Paim Hani R. El Bizri Adriano P. Paglia Helder L. Queiroz 《American journal of primatology》2019,81(6)
Population monitoring of endangered species is essential to the improvement of their management and conservation plans. The black‐headed squirrel monkey (Saimiri vanzolinii) is a vulnerable species on the IUCN Red List and has extreme geographical endemism, exhibiting the smallest known distribution among Neotropical primates (ca. 870 km2), over 90% of which occurs in white‐water flooded forests within the Mamirauá Sustainable Development Reserve (MSDR), Brazilian Amazonia. To assess the effectiveness of this protected area in conserving the species, we conducted population monitoring of black‐headed squirrel monkeys across five consecutive years (2009–2013) on nine trails 2 km each. Each year samples included both low and high river water periods. We used the distance sampling method, recording the distance to each observed social group as well as counting component individuals. We also calculated annual encounter rates based on the number of individuals sighted every 10 km traveled. Densities ranged from 256 individuals/km2 (2011) to 453 individuals/km2 (2013), and no seasonal differences were detected. Population size was estimated to be 147,848 mature individuals. Encounter rates ranged from 100 individuals/10 km (2010) to 179 individuals/10 km (2013); no significant difference among years was found. We found that S. vanzolinii populations remained stable throughout the years, which indicates that the MSDR has been playing an essential role on protecting this species. Due to difficulties of fulfilling assumptions of the distance sampling method, we consider the encounter rate analysis to be more effective for monitoring this and other Saimiri species. Given the critical endemism and worrying conservation status of S. vanzolinii, we suggest that monitoring of the species population should be carried out regularly. 相似文献
995.
Gabriela Hollmann Duane Barros Fonseca Silvana Allodi Pablo Elías Martinez Luiz Eduardo Maia Nery 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2011,197(3):293-300
Decapod crustaceans show proliferation of the nerve cells in the olfactory lobe throughout their lives. However, the regulation
of this process is still poorly understood, since it may vary with endogenous and exogenous factors. The objective of the
present investigation was to quantify the proliferation of nerve cells and number of nerve cells with ecdysone receptors in
the clusters of the central olfactory system in Neohelice granulata, according to moult stages and in different seasons (summer and winter). Three injections of bromodeoxyuridine (BrdU) were
administered to the crabs. Brains were sectioned by microtome and fixed on slides for immunohistochemistry with anti-BrdU
and anti-EcR antibodies. The proliferation of nerve cells was higher in winter than in summer, probably because in winter
the crabs do not breed and the premoult and postmoult periods are longer. Crabs in postmoult exhibited more BrdU-labelled
cells than crabs in premoult or intermoult in winter, because of a greater number of mitoses related to an increase in body
size and addition of olfactory receptor neurons. The number of EcR-labelled cells was higher in premoult than in postmoult
or intermoult in winter. The proliferation of nerve cells is regulated seasonally and according to moult stages. 相似文献
996.
Silvia Berardis Catherine Lombard Jonathan Evraerts Adil El Taghdouini Valérie Rosseels Pau Sancho-Bru Juan Jose Lozano Leo van Grunsven Etienne Sokal Mustapha Najimi 《PloS one》2014,9(1)
Adult-derived human liver stem/progenitor cells (ADHLSC) are obtained after primary culture of the liver parenchymal fraction. The cells are of fibroblastic morphology and exhibit a hepato-mesenchymal phenotype. Hepatic stellate cells (HSC) derived from the liver non-parenchymal fraction, present a comparable morphology as ADHLSC. Because both ADHLSC and HSC are described as liver stem/progenitor cells, we strived to extensively compare both cell populations at different levels and to propose tools demonstrating their singularity.ADHLSC and HSC were isolated from the liver of four different donors, expanded in vitro and followed from passage 5 until passage 11. Cell characterization was performed using immunocytochemistry, western blotting, flow cytometry, and gene microarray analyses. The secretion profile of the cells was evaluated using Elisa and multiplex Luminex assays.Both cell types expressed α-smooth muscle actin, vimentin, fibronectin, CD73 and CD90 in accordance with their mesenchymal origin. Microarray analysis revealed significant differences in gene expression profiles. HSC present high expression levels of neuronal markers as well as cytokeratins. Such differences were confirmed using immunocytochemistry and western blotting assays. Furthermore, both cell types displayed distinct secretion profiles as ADHLSC highly secreted cytokines of therapeutic and immuno-modulatory importance, like HGF, interferon-γ and IL-10.Our study demonstrates that ADHLSC and HSC are distinct liver fibroblastic cell populations exhibiting significant different expression and secretion profiles. 相似文献
997.
Hydrobiologia - The species composition, abundance and biomass of autotrophic picoplankton and larger phytoplanktonic organisms were analysed in 17 non-stratified lakes of Pomerania. Water samples... 相似文献
998.
Different capacity for phenotypic variation of Pseudomonas aurantiaca and P. fluorescens in populations of cyst-like resting cells (CRC) during their germination on solid media, was shown to be a characteristic trait of biodiversity for the dormant forms of these bacteria. This biodiversity manifests itself as qualitative and quantitative differences in the spectra and emergence frequency of phenotype variants, obtained by plating of CRC, and depends on the conditions of CRC formation and storage time. In P. aurantiaca, the variation was associated with transition of the wild-type S-colonial phenotype into the R-type or the more pigmented P-type. These transitions were most pronounced for the CRC obtained under nitrogen depletion (a twofold N limitation), as well as under the influence of a chemical analogue of microbial anabiosis autoinducers, C12-AHB. In the latter case, the frequency of S?R and S?P transitions (up to 70% and 80%, respectively) depended on the C12-AHB concentration (1.0 × 10?4 M and 2.5 × 10?4 M) and on the storage time of CRC suspensions (from 3 days to 1.3 months). In the CRC populations grown in nitrogen-deficient media, R-type appeared with a frequency of up to 45% after at least four months of storage. In the case of P. fluorescens, S?R transitions depended not only on the storage time of CRC and C12-AHB concentrations, but also on the composition of the solid medium used for plating. Differences were shown between the R-, P-, and S-variants of P. aurantiaca in such morphological, physiological, and biochemical characteristics as the growth rate (μmax) in a poor medium, biomass yield (Y max), resistance to streptomycin and tetracycline (LD50), and the productivity in extracellular proteases. The R-and S-variants of P. fluorescens differed in their growth characteristics, resistance to high salinity and oxidative stress, as well as in their sensitivity to exogenous introduction of chemical analogues of microbial autoregulators (C12-AHB and C7-AHB). Hence, both the formation of dormant forms of the various morphological types [1] and intrapopulation phenotypic variability observed during their germination are important for the survival strategy of pseudomonads under unfavorable environmental conditions. 相似文献
999.
Abdelhakim El Aoumari Catherine Fromaget Emmanuel Dupont Hubert Reggio Pascale Durbec Jean-Paul Briand Klaus Böller Bernard Kreitman Daniel Gros 《The Journal of membrane biology》1990,115(3):229-240
Summary According to the sequence of connexin 43, a cardiac gap junctional protein, the domain contained within residues 314–322 is located 60 amino acids away from the carboxy-terminus. Antibodies raised to a peptide corresponding to this domain label a unique 43-kD protein on immunoblots of both purified gap junctions and whole extracts from rat heart. Immunofluorescence investigations carried out on mammal heart sections reveal a pattern consistent with the known distribution of intercalated discs. Immunogold labeling performed with ultrathin frozen sections of rat heart or partially purified rat heart gap junctions demonstrate that antigenic determinants are associated exclusively with the cytoplasmic surfaces of gap junctions.The antibodies were shown to cross-react with a 43-kD protein on immunoblots of whole extracts from human, mouse and guinea pig heart. However, no labeling was seen when heart of lower vertebrates such as chicken, frog and trout, was investigated. These results, confirmed by immunofluorescence investigations, were interpreted as a loss of antigenic determinants due to sequence polymorphism of cardiac connexin 43.Proteins ofM
r 43 and 41 kD, immunologically related to cardiac connexin 43, were detected in immunoblots of mouse and rat brain whole extracts. mRNAs, homologous to those of cardiac connexin 43 and of the same size (3.0 kb), are also present in brain. Immunofluorescence investigations with primary cultures of unpermeabilized and permeabilized mouse neural cells showed that the antigenic determinants recognized by the antibodies specific for connexin 43 are cytoplasmic and that the labeling observed between clustered flat cells, is punctate, as expected for gap junctions. Double labeling experiments demonstrated that the immunoreactivity is associated with GFAP-positive cells, that is to say, astrocytes. 相似文献
1000.
Samir M. El Shoura 《Experimental & applied acarology》1990,9(1-2):137-143
Rod (RS) and coccoid (CS) rickettsia-like microorganisms were found in single and group forms in organs of the laboratory-reared adult ticksArgas (Persicarges) arboreus. RS are distributed in most organs but are mainly concentrated in the salivary glands, mid-gut, and testes. CS single forms were concentrated in the rectal sac, while the group forms were limited to Malpighian tubules and haemocytes of both sexes. The primary oocytes were heavily infected with both forms of CS. No RS or CS were detected in the muscles. Despite the structural differences between RS and CS, they are suggested to be different morphotypes of the same organism. 相似文献