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排序方式: 共有402条查询结果,搜索用时 15 毫秒
41.
Valentina Mariotti Benedetta Bonfiglioli Silvana Condemi 《Journal of human evolution》2009,56(4):340-354
42.
Salmona M Capobianco R Colombo L De Luigi A Rossi G Mangieri M Giaccone G Quaglio E Chiesa R Donati MB Tagliavini F Forloni G 《Journal of virology》2005,79(17):11225-11230
To investigate whether plasminogen may feature in scrapie infection, we inoculated plasminogen-deficient (Plg(-/-)), heterozygous plasminogen-deficient (Plg(+/-)), and wild-type (Plg(+/+)) mice by the intracerebral or intraperitoneal (i.p.) route with the RML scrapie strain and monitored the onset of neurological signs of disease, survival time, brain, and accumulation of scrapie disease-associated forms of the prion protein (PrP(Sc)). Only after i.p. inoculation, a slight, although significant, difference in survival (P < 0.05) between Plg(-/-) and Plg(+/+) mice was observed. Neuropathological examination and Western blot analysis were carried out when the first signs of disease appeared in Plg(+/+) animals (175 days after i.p. inoculation) and when mice reached the terminal stage of illness. At the onset of symptoms, PrP(Sc) accumulation was higher in the brain and spleen of Plg(+/+) and Plg(+/-) mice than in those of Plg(-/-) mice, and these differences were paralleled by differences in the severity of spongiform changes and astrogliosis in the cerebral cortex and subcortical gray structures. Immunohistochemical analysis of the spleens before inoculation did not show any impairment of the immune system affecting follicular dendritic or lymphoid cells in Plg(-/-) mice. Once the disease progressed and mice began to die of infection, differences were no longer apparent in either brains or spleens. In conclusion, our data indicate that plasminogen has no major effect on the survival of scrapie agent-infected mice. 相似文献
43.
Zannini C Turchetti S Guarch R Buffa D Pesce C 《Analytical and quantitative cytology and histology / the International Academy of Cytology [and] American Society of Cytology》1999,21(4):358-362
OBJECTIVE: To collect quantitative and stereologic data on the main cell types represented in the seminiferous tubule in order to produce a three-dimensional representation of the morphologic events of normal cell production and maturation. STUDY DESIGN: Three-dimensional reconstruction and differential cell counting were performed on serial sections of normal testicular tissue from normal young men through image analysis and computer-based rendering. RESULTS: Peculiar periodicity in the total number of tubular cells considered along the sequence of serial sections was recognized. Also, consensual periodicity pertaining to each cell type was recognized. Adjacent high cellularity and low cellularity segments included a fairly constant mixture of cell types considered. CONCLUSION: A newly defined cellular wave, composed of regular alternations of high and low cellularity segments, was identified in the normal human seminiferous tubule. 相似文献
44.
45.
Two of the five known mammalian 5'-nucleotidases show a preference for the dephosphorylation of deoxynucleoside-5'-phosphates. One is a cytoplasmic enzyme (dNT-1), the other occurs in mitochondria (dNT-2). The human mitochondrial enzyme, recently discovered and cloned by us, is encoded by a nuclear gene located on chromosome 17 p11.2 in the critical region deleted in the Smith-Magenis syndrome (SMS), a genetic disease of unknown etiology. Looking for a model system to study the possible involvement of dNT-2 in the disease, we have cloned the cDNA of the mouse ortholog. The deduced protein sequence is 84% identical to the human ortholog, has a very basic NH(2)-terminus, a very high calculated probability of being imported into mitochondria and contains the DXDXT/V motif conserved among nucleotidases. Expression in Escherichia coli of the predicted processed form of the protein produced an active deoxyribonucleotidase. We also identified in genomic sequences present in the data base the structures of the murine genes for the cytosolic and mitochondrial deoxyribonucleotidases (Nt5c and Nt5m). PAC clones for the two loci were isolated from a library and used for chromosomal localization by fluorescent in situ hybridization. Both genes map on chromosome 11: Nt5c at 11E and Nt5m at 11B, demonstrating the presence of the dNT-2 locus in the mouse shaker-2 critical region, the murine counterpart of the human SMS region. We performed pair-wise dot-plot and PIP (percent identity plot) analyses of mouse and human deoxyribonucleotidase genes, and found a strong conservation that extends also to some intronic sequences of possible regulatory significance. 相似文献
46.
Thatjana Gardeitchik Miski Mohamed Benedetta Ruzzenente Daniela Karall Sergio Guerrero-Castillo Daisy Dalloyaux Mariël van den Brand Sanne van Kraaij Ellyze van Asbeck Zahra Assouline Marlene Rio Pascale de Lonlay Sabine Scholl-Buergi David F.G.J. Wolthuis Alexander Hoischen Richard J. Rodenburg Wolfgang Sperl Zsolt Urban Eva Morava 《American journal of human genetics》2018,102(4):685-695
47.
Tatiane A. Paixão Marcelo C. C. Malta Semíramis A. Soave Herlandes P. Tinoco Maria E.L.T. Costa Angela T. Pessanha Rodrigo O.S. Silva Fernanda M. Coura Luciana F. Costa Andreia P. Turchetti Francisco C.F. Lobato Marilia M. Melo Marcos B. Heinemann Renato L. Santos 《Journal of medical primatology》2014,43(2):118-121
48.
Nicole J. Lake Bryn D. Webb David A. Stroud Tara R. Richman Benedetta Ruzzenente Alison G. Compton Hayley S. Mountford Juliette Pulman Coralie Zangarelli Marlene Rio Nathalie Boddaert Zahra Assouline Mingma D. Sherpa Eric E. Schadt Sander M. Houten James Byrnes Elizabeth M. McCormick Zarazuela Zolkipli-Cunningham David R. Thorburn 《American journal of human genetics》2018,102(4):713
49.
Reinier Oropesa-Nuñez Sandeep Keshavan Silvia Dante Alberto Diaspro Benedetta Mannini Claudia Capitini Cristina Cecchi Massimo Stefani Fabrizio Chiti Claudio Canale 《Biophysical journal》2018,114(6):1357-1367
The deposition of fibrillar protein aggregates in human organs is the hallmark of several pathological states, including highly debilitating neurodegenerative disorders and systemic amyloidoses. It is widely accepted that small oligomers arising as intermediates in the aggregation process, released by fibrils, or growing in secondary nucleation steps are the cytotoxic entities in protein-misfolding diseases, notably neurodegenerative conditions. Increasing evidence indicates that cytotoxicity is triggered by the interaction between nanosized protein aggregates and cell membranes, even though little information on the molecular details of such interaction is presently available. In this work, we propose what is, to our knowledge, a new approach, based on the use of single-cell force spectroscopy applied to multifunctional substrates, to study the interaction between protein oligomers, cell membranes, and/or the extracellular matrix. We compared the interaction of single Chinese hamster ovary cells with two types of oligomers (toxic and nontoxic) grown from the N-terminal domain of the Escherichia coli protein HypF. We were able to quantify the affinity between both oligomer type and the cell membrane by measuring the mechanical work needed to detach the cells from the aggregates, and we could discriminate the contributions of the membrane lipid and protein fractions to such affinity. The fundamental role of the ganglioside GM1 in the membrane-oligomers interaction was also highlighted. Finally, we observed that the binding of toxic oligomers to the cell membrane significantly affects the functionality of adhesion molecules such as Arg-Gly-Asp binding integrins, and that this effect requires the presence of the negatively charged sialic acid moiety of GM1. 相似文献
50.
Alexandra Kukat Eduard Hofsetz Hendrik Nolte Katharina Senft Christina Becker Benedetta Ruzzenente Hue‐Tran Hornig‐Do Rolf Wibom Rudolf J Wiesner Marcus Krüger Aleksandra Trifunovic 《The EMBO journal》2016,35(23):2566-2583
Despite being one of the most studied proteases in bacteria, very little is known about the role of ClpXP in mitochondria. We now present evidence that mammalian CLPP has an essential role in determining the rate of mitochondrial protein synthesis by regulating the level of mitoribosome assembly. Through a proteomic approach and the use of a catalytically inactive CLPP, we produced the first comprehensive list of possible mammalian ClpXP substrates involved in the regulation of mitochondrial translation, oxidative phosphorylation, and a number of metabolic pathways. We further show that the defect in mitoribosomal assembly is a consequence of the accumulation of ERAL1, a putative 12S rRNA chaperone, and novel ClpXP substrate. The presented data suggest that the timely removal of ERAL1 from the small ribosomal subunit is essential for the efficient maturation of the mitoribosome and a normal rate of mitochondrial translation. 相似文献