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91.
Domenico Rau Maria L. Murgia Monica Rodriguez Elena Bitocchi Elisa Bellucci Davide Fois Diego Albani Laura Nanni Tania Gioia Debora Santo Luca Marcolungo Massimo Delledonne Giovanna Attene Roberto Papa 《The Plant journal : for cell and molecular biology》2019,97(4):693-714
The complete or partial loss of shattering ability occurred independently during the domestication of several crops. Therefore, the study of this trait can provide an understanding of the link between phenotypic and molecular convergent evolution. The genetic dissection of ‘pod shattering’ in Phaseolus vulgaris is achieved here using a population of introgression lines and next‐generation sequencing techniques. The ‘occurrence’ of the indehiscent phenotype (indehiscent versus dehiscent) depends on a major locus on chromosome 5. Furthermore, at least two additional genes are associated with the ‘level’ of shattering (number of shattering pods per plant: low versus high) and the ‘mode’ of shattering (non‐twisting versus twisting pods), with all of these loci contributing to the phenotype by epistatic interactions. Comparative mapping indicates that the major gene identified on common bean chromosome 5 corresponds to one of the four quantitative trait loci for pod shattering in Vigna unguiculata. None of the loci identified comprised genes that are homologs of the known shattering genes in Glycine max. Therefore, although convergent domestication can be determined by mutations at orthologous loci, this was only partially true for P. vulgaris and V. unguiculata, which are two phylogenetically closely related crop species, and this was not the case for the more distant P. vulgaris and G. max. Conversely, comparative mapping suggests that the convergent evolution of the indehiscent phenotype arose through mutations in different genes from the same underlying gene networks that are involved in secondary cell‐wall biosynthesis and lignin deposition patterning at the pod level. 相似文献
92.
93.
Mohammad S Baldini G Granell S Narducci P Martelli AM Baldini G 《The Journal of biological chemistry》2007,282(7):4963-4974
Melanocortin-4 receptor (MC4R) is a G protein-coupled receptor (GPCR) that binds alpha-melanocyte-stimulating hormone (alpha-MSH) and has a central role in the regulation of appetite and energy expenditure. Most GPCRs are endocytosed following binding to the agonist and receptor desensitization. Other GPCRs are internalized and recycled back to the plasma membrane constitutively, in the absence of the agonist. In unstimulated neuroblastoma cells and immortalized hypothalamic neurons, epitopetagged MC4R was localized both at the plasma membrane and in an intracellular compartment. These two pools of receptors were in dynamic equilibrium, with MC4R being rapidly internalized and exocytosed. In the absence of alpha-MSH, a fraction of cell surface MC4R localized together with transferrin receptor and to clathrin-coated pits. Constitutive MC4R internalization was impaired by expression of a dominant negative dynamin mutant. Thus, MC4R is internalized together with transferrin receptor by clathrin-dependent endocytosis. Cell exposure toalpha-MSH reduced the amount of MC4R at the plasma membrane by blocking recycling of a fraction of internalized receptor, rather than by increasing its rate of endocytosis. The data indicate that, in neuronal cells, MC4R recycles constitutively and that alpha-MSH modulates MC4R residency at the plasma membrane by acting at an intracellular sorting step. 相似文献
94.
Orefice Ida Di Dato Valeria Sardo Angela Lauritano Chiara Romano Giovanna 《Aquatic Ecology》2022,56(2):377-397
Aquatic Ecology - Diatoms are eukaryotic microalgae representing one of the major groups in the marine phytoplankton, accounting for up to 40% of annual productivity at sea. They are widely... 相似文献
95.
Giacomo Pozzoli Hany E. Marei Asma Althani Alma Boninsegna Patrizia Casalbore Lionel N. J. L. Marlier Giulia Lanzilli Manuela Zonfrillo Giovanna Petrucci Bianca Rocca Pierluigi Navarra Alessandro Sgambato Carlo Cenciarelli 《Journal of cellular physiology》2019,234(9):15459-15471
Several clinical studies indicated that the daily use of aspirin or acetylsalicylic acid reduces the cancer risk via cyclooxygenases (Cox-1 and Cox-2) inhibition. In addition, aspirin-induced Cox-dependent and -independent antitumor effects have also been described. Here we report, for the first time, that aspirin treatment of human glioblastoma cancer (GBM) stem cells, a small population responsible for tumor progression and recurrence, is associated with reduced cell proliferation and motility. Aspirin did not interfere with cell viability but induced cell-cycle arrest. Exogenous prostaglandin E2 significantly increased cell proliferation but did not abrogate the aspirin-mediated growth inhibition, suggesting a Cox-independent mechanism. These effects appear to be mediated by the increase of p21 waf1 and p27 Kip1, associated with a reduction of Cyclin D1 and Rb1 protein phosphorylation, and involve the downregulation of key molecules responsible for tumor development, that is, Notch1, Sox2, Stat3, and Survivin. Our results support a possible role of aspirin as adjunctive therapy in the clinical management of GBM patients. 相似文献
96.
Francesca Chiarini Francesca Paganelli Tommaso Balestra Cristina Capanni Antonietta Fazio Maria Cristina Manara Lorena Landuzzi Stefania Petrini Camilla Evangelisti Pier-Luigi Lollini Alberto M. Martelli Giovanna Lattanzi Katia Scotlandi 《Cell death & disease》2022,13(4)
Lamin A, a main constituent of the nuclear lamina, is involved in mechanosignaling and cell migration through dynamic interactions with the LINC complex, formed by the nuclear envelope proteins SUN1, SUN2 and the nesprins. Here, we investigated lamin A role in Ewing Sarcoma (EWS), an aggressive bone tumor affecting children and young adults. In patients affected by EWS, we found a significant inverse correlation between LMNA gene expression and tumor aggressiveness. Accordingly, in experimental in vitro models, low lamin A expression correlated with enhanced cell migration and invasiveness and, in vivo, with an increased metastatic load. At the molecular level, this condition was linked to altered expression and anchorage of nuclear envelope proteins and increased nuclear retention of YAP/TAZ, a mechanosignaling effector. Conversely, overexpression of lamin A rescued LINC complex organization, thus reducing YAP/TAZ nuclear recruitment and preventing cell invasiveness. These effects were also obtained through modulation of lamin A maturation by a statin-based pharmacological treatment that further elicited a more differentiated phenotype in EWS cells. These results demonstrate that drugs inducing nuclear envelope remodeling could be exploited to improve therapeutic strategies for EWS.Subject terms: Nuclear organization, Cancer 相似文献
97.
Daniela Accili Maura Menghi Giovanni Materazzi Giovanna Menghi 《The Histochemical journal》2001,33(6):363-371
Sialoglycoconjugates in rat sublingual gland acinar cells, at different stages of pre- and post-natal development, were investigated in situ with specific lectins and by the selective removal of terminal sialic acids. Cleavage of acetyl substituents sited in the pyranose ring and/or polyhydroxyl side chain was used as an additional means of characterising the glycoconjugates. The first expression of terminal sialic acid linked to -galactose was found at gestational day 17 and progressive different derivatives were observed. The terminal disaccharide sialic acid-N-acetylgalactosamine was constantly visualized in the sublingual gland from gestational day 18. In both terminal disaccharides, sialic acids were characterized by variable degrees of acetylation and were found to be highly packaged and responsible for the hydration coat. The complex data obtained indicated that the sublingual gland is characterized by a marked fluctuation of complex sialoglycoconjugates that differ from those in the submandibular gland of the same species. 相似文献
98.
Giovanna De Matteis Enzo Agostinelli Bruno Mondovì L. Morpurgo 《Journal of biological inorganic chemistry》1999,4(3):348-353
Bovine serum amine oxidase (BSAO) reacts with 2-hydrazinopyridine, which binds the organic cofactor 2,4,5-trihydroxyphenylalanine
quinone, forming a band at 435 nm. The band shifts to 526 nm around 60 °C, to 415 nm upon denaturation, but only shifts to
429 nm upon Cu2+ depletion. Its wavelength and intensity suggest that the adduct has the azo conformation, whilst the same adduct of crystallineEscherichia coli amine oxidase (ECAO) shows the hydrazone conformation in the X-ray structure. The steady state kinetics of aminomethyl- and
aminoethylpyridines confirm that the formation of the product Schiff base, analogous to the azo form of the 2-hydrazinopyridine
adduct, is not hindered in solution. The structural stability of the adduct in the absence of Cu2+ is taken to imply hydrogen bonding of the pyridyl nitrogen to a conserved aspartate, as in the ECAO adduct. Thus the ECAO
adduct provides a good model for a transient intermediate leading to formation of the BSAO azo adduct. On the basis of this
model and of the catalytic competence of Co2+-substituted BSAO, confirmed by the present data, a catalytic reaction scheme is proposed.
Received: 2 December 1998 / Accepted: 22 March 1999 相似文献
99.
B. Yassine-Diab P. Carmichael Fatima-Ezzahra L'Faqihi Giovanna Lombardi Sarah Deacock Claude de Préval Hélène Coppin R. I. Lechler 《Immunogenetics》1999,49(6):532-540
A comprehensive analysis was carried out of the tri-molecular complex of peptide, major histocompatibility class II molecule,
and T-cell receptor (TcR) involved in the recognition of the promiscuous HA (306–318) peptide, restricted by one of two closely
related HLA-DR alleles, HLA-DRB1*0101 and HLA-DRB1*0103. These two DR molecules differ by only three amino acids at positions 67, 70, and 71, in the third variable region of the
DRB1 chain. None of the HA (306–318)-specific T-cell clones restricted by these two DR molecules tolerated amino acid substitution
at the peptide-binding position 71, despite the fact that the substitution did not interfere with peptide binding. The majority
of the DRB1*0103-restricted clones tolerated substitution of the amino acid at the TcR-contacting position 70, while the DRB1*0101-restricted
T cells did not. Biased usage of TRVA and TRVB segments was observed for the DRB1*0103-restricted clones; in contrast, apparently
random usage was seen in the DRB1*0101-restricted T cells. Finally, limiting dilution analysis revealed a lower frequency
of T cells reactive with the HA peptide in a DRB1*0103 compared with a DRB1*0101 individual. Taken together these data suggest
that biased TcR gene usage may reflect a relatively low precursor frequency of T cells, and the need for clonal expansion of a limited set
of high avidity T cells.
Received: 7 August 1998 / Revised: 19 November 1998 相似文献
100.
Semprini S Capon F Bovolenta S Bruscia E Pizzuti A Fabrizi G Schietroma C Zambruno G Dallapiccola B Novelli G 《Human genetics》1999,104(2):130-134