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排序方式: 共有692条查询结果,搜索用时 750 毫秒
51.
Domenico De Rasmo Giuseppe Palmisano Salvatore Scacco Zuzana Technikova-Dobrova Damiano Panelli Tiziana Cocco Anna Maria Sardanelli Antonio Gnoni Loris Micelli Antonio Trani Aldo Di Luccia Sergio Papa 《Mitochondrion》2010,10(5):464-471
The NDUFS4 subunit of complex I of the mammalian respiratory chain has a fully conserved carboxy-terminus with a canonical RVSTK phosphorylation site. Immunochemical analysis with specific antibodies shows that the serine in this site of the protein is natively present in complex I in both the phosphorylated and non-phosphorylated state. Two-dimensional IEF/SDS–PAGE electrophoresis, 32P labelling and immunodetection show that “in vitro” PKA phosphorylates the serine in the C-terminus of the NDUFS4 subunit in isolated bovine complex I. 32P labelling and TLC phosphoaminoacid mapping show that PKA phosphorylates serine and threonine residues in the purified heterologous human NDUFS4 protein. 相似文献
52.
A. Bertuzzi C. Bruni A. Fasano A. Gandolfi F. Papa C. Sinisgalli 《Bulletin of mathematical biology》2010,72(5):1069-1091
We propose a spatially distributed continuous model for the spheroid response to radiation, in which the oxygen distribution
is represented by means of a diffusion-consumption equation and the radiosensitivity parameters depend on the oxygen concentration.
The induction of lethally damaged cells by a pulse of radiation, their death, and the degradation of dead cells are included.
The compartments of lethally damaged cells and of dead cells are subdivided into different subcompartments to simulate the
delays that occur in cell death and cell degradation, with a gain in model flexibility. It is shown that, for a single irradiation
and under the hypothesis of a sufficiently small spheroid radius, the model can be reformulated as a linear stationary ordinary
differential equation system. For this system, the parameter identifiability has been investigated, showing that the set of
unknown parameters can be univocally identified by exploiting the response of the model to at least two different radiation
doses. Experimental data from spheroids originated from different cell lines are used to identify the unknown parameters and
to test the predictive capability of the model with satisfactory results. 相似文献
53.
54.
S. A. Angioi D. Rau G. Attene L. Nanni E. Bellucci G. Logozzo V. Negri P. L. Spagnoletti Zeuli R. Papa 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2010,121(5):829-843
This study focuses on the expansion of Phaseolus vulgaris in Europe. The pathways of distribution of beans into and across Europe were very complex, with several introductions from
the New World that were combined with direct exchanges between European and other Mediterranean countries. We have analyzed
here six chloroplast microsatellite (cpSSR) loci and two unlinked nuclear loci (for phaseolin types and Pv-shatterproof1). We have assessed the genetic structure and level of diversity of a large collection of European landraces of P. vulgaris (307) in comparison to 94 genotypes from the Americas that are representative of the Andean and Mesoamerican gene pools.
First, we show that most of the European common bean landraces (67%) are of Andean origin, and that there are no strong differences
across European regions for the proportions of the Andean and Mesoamerican gene pools. Moreover, cytoplasmic diversity is
evenly distributed across European regions. Secondly, the cytoplasmic bottleneck that was due to the introduction of P. vulgaris into the Old World was very weak or nearly absent. This is in contrast to evidence from nuclear analyses that have suggested
a bottleneck of greater intensity. Finally, we estimate that a relatively high proportion of the European bean germplasm (about
44%) was derived from hybridization between the Andean and Mesoamerican gene pools. Moreover, although hybrids are present
everywhere in Europe, they show an uneven distribution, with high frequencies in central Europe, and low frequencies in Spain
and Italy. On the basis of these data, we suggest that the entire European continent and not only some of the countries therein
can be regarded as a secondary diversification center for P. vulgaris. Finally, we outline the relevance of these inter-gene pool hybrids for plant breeding. 相似文献
55.
Insights into the structural basis of the GADD45beta-mediated inactivation of the JNK kinase, MKK7/JNKK2 总被引:1,自引:0,他引:1
Papa S Monti SM Vitale RM Bubici C Jayawardena S Alvarez K De Smaele E Dathan N Pedone C Ruvo M Franzoso G 《The Journal of biological chemistry》2007,282(26):19029-19041
NF-kappaB/Rel factors control programmed cell death (PCD), and this control is crucial to oncogenesis, cancer chemoresistance, and antagonism of tumor necrosis factor (TNF) alpha-induced killing. With TNFalpha, NF-kappaB-mediated protection involves suppression of the c-Jun-N-terminal kinase (JNK) cascade, and we have identified Gadd45beta, a member of the Gadd45 family, as a pivotal effector of this activity of NF-kappaB. Inhibition of TNFalpha-induced JNK signaling by Gadd45beta depends on direct targeting of the JNK kinase, MKK7/JNKK2. The mechanism by which Gadd45beta blunts MKK7, however, is unknown. Here we show that Gadd45beta is a structured protein with a predicted four-stranded beta-sheet core, five alpha-helices, and two acidic loops. Association of Gadd45beta with MKK7 involves a network of interactions mediated by its putative helices alpha3 and alpha4 and loops 1 and 2. Whereas alpha3 appears to primarily mediate docking to MKK7, loop 1 and alpha4-loop 2 seemingly afford kinase inactivation by engaging the ATP-binding site and causing conformational changes that impede catalytic function. These data provide a basis for Gadd45beta-mediated blockade of MKK7, and ultimately, TNFalpha-induced PCD. They also have important implications for treatment of widespread diseases. 相似文献
56.
57.
Identifying prosurvival mechanisms in stressed neuronal cells would provide protective strategies to hinder neurodegeneration.
Recent evidence shows that vascular endothelial growth factor (VEGF), a well-established mitogen in endothelial cells, can
mediate neuroprotection against damaging insults through the activation of its cognate receptor VEGFR2. In addition, growth
factor receptor signaling pathways have been shown to crosstalk with cAMP-dependent Protein Kinase A (PKA) to protect neuronal
cells from harmful stimuli. Whether a relationship exists between VEGFR2 and PKA in mediating neuroprotection under stressful
conditions is unknown. Using SK-N-SH neuronal cells as a model system, we show that serum deprivation induces an upregulation
in VEGF and VEGFR2 that concomitantly serves as a prosurvival signaling pathway. Inhibitor studies revealed that PKA functioned
concurrently with VEGFR2 pathway to signal the activation of the extracellular signal-regulated protein kinases (ERK1/2) as
protection against caspase-3/7 activation and a subsequent cell death. The loss in cell viability induced by VEGFR2 and PKA
inhibition was prevented by caspase inhibition or overexpression of ERK1. Overexpression of the antiapoptotic protein Bcl-xL
also promoted survival when VEGFR2 function was blocked. However, the protection elicited by all three treatments were prevented
by the inclusion of a selective inhibitor of mitogen-activated protein kinase kinase (MEK), the upstream kinase that activates
ERK1/2. Taken together, these findings suggested that PKA and VEGFR2 converge at the MEK/ERK1/2 pathway to protect serum starved
neuronal cells from a caspase-dependent cell death.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
58.
Nonmetric cranial traits have been commonly used in evolutionary relationship studies. They develop during the growth and development of an individual, and for this reason its expression presents different sources of genetic and nongenetic variation. However, the use of these features in evolutionary relationship studies carries the implicit assumption that much of the nonmetric trait variation is essentially genetic. Among the nonheritable factors, cranial vault deformation has been the most studied in human populations. Because of the widespread distribution and elevated rate of artificial cranial vault deformation found in America, and the importance of nonmetric traits in evolutionary relationship studies in this area, the objectives of this paper are as follows: (a) to study the influence of artificial cranial vault deformation on the presence of nonmetric traits within samples of human craniofacial remains; and (b) to establish artificial cranial vault deformation influence on evolutionary relationships between local populations on a regional scale. Our results indicate that artificial cranial vault deformations alter the variation and covariation of metric and nonmetric traits in some samples. Wormian bones, placed in cranial vault sutures, are the most influenced by this factor. However, our results suggest that when all nonmetric traits were used the artificial cranial vault deformation did not influence the basic pattern of variation among samples. The exclusion or inclusion of wormians bones in evolutionary relationships analysis did not modify the results, but using only wormians bones lead to inconsistent results indicating that these traits have little value on these kind of studies. 相似文献
59.
Centeno C Repici M Chatton JY Riederer BM Bonny C Nicod P Price M Clarke PG Papa S Franzoso G Borsello T 《Cell death and differentiation》2007,14(2):240-253
Excitotoxic insults induce c-Jun N-terminal kinase (JNK) activation, which leads to neuronal death and contributes to many neurological conditions such as cerebral ischemia and neurodegenerative disorders. The action of JNK can be inhibited by the D-retro-inverso form of JNK inhibitor peptide (D-JNKI1), which totally prevents death induced by N-methyl-D-aspartate (NMDA) in vitro and strongly protects against different in vivo paradigms of excitotoxicity. To obtain optimal neuroprotection, it is imperative to elucidate the prosurvival action of D-JNKI1 and the death pathways that it inhibits. In cortical neuronal cultures, we first investigate the pathways by which NMDA induces JNK activation and show a rapid and selective phosphorylation of mitogen-activated protein kinase kinase 7 (MKK7), whereas the only other known JNK activator, mitogen-activated protein kinase kinase 4 (MKK4), was unaffected. We then analyze the action of D-JNKI1 on four JNK targets containing a JNK-binding domain: MAPK-activating death domain-containing protein/differentially expressed in normal and neoplastic cells (MADD/DENN), MKK7, MKK4 and JNK-interacting protein-1 (IB1/JIP-1). 相似文献
60.
Gao Xiang Uno Kenichi Sarr Papa Saliou Yoshihashi Tadashi Zhu Yiyong Subbarao Guntur Venkata 《Plant and Soil》2022,477(1-2):793-805
Plant and Soil - Rapid nitrification leads to loss of nitrogen (N) fertilizer in agricultural systems. Plant produced/derived biological nitrification inhibitors (BNIs) are an effective... 相似文献