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991.
Sara Savelli Luisa Trombi Delfo DAlessandro Stefania Moscato Simone Pacini Stefano Giannotti Simone Lapi Fabrizio Scatena Mario Petrini 《Cytotherapy》2018,20(4):556-563
Background
Bone Marrow MSCs are an appealing source for several cell-based therapies. Many bioreactors, as the Quantum Cell Expansion System, have been developed to generate a large number of MSCs under Good Manufacturing Practice conditions by using Human Platelet Lysate (HPL). Previously we isolated in the human bone marrow a novel cell population, named Mesodermal Progenitor Cells (MPCs), which we identified as precursors of MSCs. MPCs could represent an important cell source for regenerative medicine applications. As HPL gives rise to a homogeneus MSC population, limiting the harvesting of other cell types, in this study we investigated the efficacy of pooled human AB serum (ABS) to provide clinically relevant numbers of both MSCs and MPCs for regenerative medicine applications by using the Quantum System.Methods
Bone marrow aspirates were obtained from healthy adult individuals undergoing routine total hip replacement surgery and used to generate primary cultures in the bioreactor. HPL and ABS were tested as supplements to culture medium. Morphological observations, cytofluorimetric analysis, lactate and glucose level assessment were performed.Results
ABS gave rise to both heterogeneous MSC and MPC population. About 95% of cells cultured in HPL showed a fibroblast-like morphology and typical mesenchymal surface markers, but MPCs were scarcely represented.Discussion
The use of ABS appeared to sustain a large scale MSC production, as well as the recovery of a subset of MPCs, and resulted a suitable alternative to HPL in the cell generation based on the Quantum System. 相似文献992.
Gaetana Paolella Marilena Lepretti Stefania Martucciello Merlin Nanayakkara Salvatore Auricchio Carla Esposito Maria Vittoria Barone Ivana Caputo 《Cell biology international》2018,42(1):112-120
Alpha‐gliadin peptide 31–43 is considered to be the main peptide responsible for the innate immune response in celiac disease patients. Recent evidence indicates that peptide 31–43 rapidly enters cells and interacts with the early endocytic vesicular compartment. However, the mechanism of its uptake is not completely understood. Our aim is to characterize, isolate and identify possible cell surface proteins involved in peptide 31–43 internalization by Caco‐2 cells. In this study, we used a chemical cross‐linker to block peptide 31–43 on cell surface proteins, and pulled‐down peptide‐proteins complexes using antibodies raised against peptide 31–43. Through this experimental approach, we did not observe any specific complex between cell proteins and peptide 31–43 in Coomassie‐stained denaturating gels or by Western blotting. We also found that type 2 transglutaminase was not necessary for peptide 31–43 internalization, even though it had a regulatory role in the process. Finally, we demonstrated that peptide 31–43 did not behave as a classical ligand, indeed the labeled peptide did not displace the unlabeled peptide in a competitive binding assay. On the basis of these findings and of previous evidence demonstrating that peptide 31–43 is able to interact with a membrane‐like environment in vitro, we conclude that membrane composition and organization, rather than a specific receptor protein, may have a major role in peptide 31–43 internalization by cells. 相似文献
993.
Paola Punzo Alessandra Ruggiero Marco Possenti Roberta Nurcato Antonello Costa Giorgio Morelli Stefania Grillo Giorgia Batelli 《The Plant journal : for cell and molecular biology》2018,94(6):991-1009
Modulation of growth in response to environmental cues is a fundamental aspect of plant adaptation to abiotic stresses. TIP41 (TAP42 INTERACTING PROTEIN OF 41 kDa) is the Arabidopsis thaliana orthologue of proteins isolated in mammals and yeast that participate in the Target‐of‐Rapamycin (TOR) pathway, which modifies cell growth in response to nutrient status and environmental conditions. Here, we characterized the function of TIP41 in Arabidopsis. Expression analyses showed that TIP41 is constitutively expressed in vascular tissues, and is induced following long‐term exposure to NaCl, polyethylene glycol and abscisic acid (ABA), suggesting a role of TIP41 in adaptation to abiotic stress. Visualization of a fusion protein with yellow fluorescent protein indicated that TIP41 is localized in the cytoplasm and the nucleus. Abolished expression of TIP41 results in smaller plants with a lower number of rosette leaves and lateral roots, and an increased sensitivity to treatments with chemical TOR inhibitors, indicating that TOR signalling is affected in these mutants. In addition, tip41 mutants are hypersensitive to ABA at germination and seedling stage, whereas over‐expressing plants show higher tolerance. Several TOR‐ and ABA‐responsive genes are differentially expressed in tip41, including iron homeostasis, senescence and ethylene‐associated genes. In yeast and mammals, TIP41 provides a link between the TOR pathway and the protein phosphatase 2A (PP2A), which in plants participates in several ABA‐mediated mechanisms. Here, we showed an interaction of TIP41 with the catalytic subunit of PP2A. Taken together, these results offer important insights into the function of Arabidopsis TIP41 in the modulation of plant growth and ABA responses. 相似文献
994.
Filiberto Belli Flavio Arienti J. Sulé-Suso C. Clemente Luigi Mascheroni Alessandro Cattelan Cristina Santantonio Gian Francesco Gallino Cecilia Melani Stefania Rao Mario P. Colombo Michele Maio Natale Cascinelli G. Parmiani 《Cancer immunology, immunotherapy : CII》1997,44(4):197-203
From January 1994 to July 1996 we immunized metastatic melanoma patients with HLA-A2-compatible, interleukin-2 (IL-2)-secreting,
immunogenic melanoma lines in an attempt to induce a systemic reaction that might also affect distant melanoma lesions. Twelve
patients (6 male and 6 female) aged from 28 to 72 years, affected with visceral and/or subcutaneous (s.c.) melanoma metastases,
were treated. Two different HLA-A2+ melanoma lines were transduced with the human IL-2 gene (14932/IL-2 and 1B6/IL-2) and used as vaccine. Two groups of 4 patients
each were injected s.c. with 5×107 and 15×107 irradiated 14932/IL-2 melanoma cells respectively, whereas a third group received 5×107 cells of the second line (1B6/IL-2). All patients received the vaccine on days 1, 13, 26; if no progression was evident,
further immunizations were administered at monthly intervals. All patients were assessable for clinical response after at
least three injections of the vaccine. In 4 cases a stabilization of disease lasting from 2 to 6 months was observed; in 2
of them a mixed type of response to treatment was noted with simultaneous evidence of regressing and non-responding lesions
in the same patients. No signs of clinical response were found in the remaining patients. Nine patients died of disease between
3 and 24 months after the onset of therapy, whereas 3 were alive 3 months after the end of therapy. The local and systemic
side-effects of treatment were mild. These results indicate that vaccination with cells bearing the appropriate antigens and
releasing IL-2 locally can produce weak clinical responses, but also indicate that better results may be achieved through
modifications of the vaccine, the schedule of immunization and/or a more appropriate selection of patients.
Received: 20 December 1996 / Accepted: 27 February 1997 相似文献
995.
CO2 assimilation, xanthophyll cycle pigments and PSII efficiency in pumpkin plants as affected by ozone fumigation 总被引:2,自引:0,他引:2
Stefania Ciompi Antonella Castagna Annamaria Ranieri Cristina Nali Giacomo Lorenzini Gian Franco Soldatini 《Physiologia plantarum》1997,101(4):881-889
CO2 assimilation, xanthophyll cycle pigments and PSII efficiency were analyzed in two different ages of pumpkin leaves (Cucurbita pepo L. cv. Ambassador) exposed to 150 nmol mol-1 of ozone (5 days, 5 h day-1). Gas-exchange measurements revealed a reduction in CO2 assimilation and stomatal conductance, accompanied by an increase in the intercellular CO2 concentration both in young and in mature leaves as compared to their respective controls. In both leaves, F0 remained unchanged, while Fm and the Fv/Fm ratio decreased after O3 fumigation, indicating that ozone may induce an alteration in the capability of photosystem II (PSII) to reduce the primary acceptor QA. In the mature leaves the photochemical quenching (qp) was significantly lowered by the pollutant, but this was not the case in the young leaves where qp did not change. In both mature and young ozonated pumpkin leaves, the development of non-photochemical quenching caused a decrease in the PSII photochemical rate, as shown by the correlation between Fv/Fm and the de-epoxidation state of dark-adapted leaves. Decreases in the Fv/Fm ratio are generally attributed to damage to the PSII reaction centre, apart from the down-regulation of the capacity of PSII electron transport. While in young ozonated leaves the decrease in the Fv/Fm ratio was not associated with damage to the D1 protein, in mature ozonated pumpkin leaves, the decrease in the Fv/Fm was accompanied by a significant decline in the D1 content. In conclusion, ozone exposure induces alterations in the light reactions of photosynthesis in both young and mature leaves. However, in young leaves the engagement of the xanthophyll cycle appears to counteract ozone effects against the photosynthetic apparatus as demonstrated by the absence of damage to the D1 protein. On the other hand, the loss of D1 protein in mature fumigated leaves suggests that the activation of the xanthophyll cycle is not sufficient to prevent photoinhibition, probably because a physiological state of senescence adds to the oxidative stress. 相似文献
996.
997.
Fabrizia Fusetti Stefania Brocca Danilo Porro Marina Lotti 《Biotechnology letters》1996,18(3):281-286
Summary The Candida rugosa lipase I gene has been expressed in Saccharomyces cerevisiae. The recombinant lipase was efficiently synthesized only following the replacement of the enzyme endogenous leader sequence with the signal peptide of the Kluyveromyces lactis killer toxin. Amount of accumulated lipase was about 10–20 mg/l in batch culture and over 1g/l in a computer-controlled fed-batch fermentation system. 相似文献
998.
Maria S. Ristaldi Stefania Casula Andrea Rando Rita Vestri 《Journal of molecular evolution》1995,40(4):349-353
In sheep as in man and most other mammals, there are two -globin genes (I and II), which are expressed at different levels, the upstream gene being the most efficient. In -globin gene triplication and quadruplication, this trend is confirmed, i.e., the -chain output of the downstream genes progressively decreases. In this study, we have determined the complete sequence of the cDNAs and of both the introns in a triple- haplotype in which each gene could be recognized for the presence of distinct alleles. The sequence analysis reveals that the bodies of the three -globin genes are essentially identical (99.9% homology) and moreover indicates that the down-regulation of additional -globin genes in sheep is not the effect of sequence variation from the Cap to the Poly(A) addition sites. This striking similarity among -genes is higher than that seen in other mammals and is probably sustained by particularly efficient mechanisms of gene conversion and cross-over fixation.
Correspondence to: Dr. M.S. Ristaldi 相似文献
999.
Paola Goldoni Lorena Cattani Stefania Carrara Maddalena Castellani Pastoris Laura Sinibaldi Nicola Orsi 《Microbiology and immunology》1998,42(4):271-279
A study has been carried out on the action of cytoskeleton and metabolic inhibitors on intracellular multiplication in HeLa cells of a virulent strain of Legionella pneumophila serogroup 6. The effects of the substances were separately tested on both penetration and intracellular multiplication of L. pneumophila. Only cytochalasin A and 2-deoxy-d -glucose (2dG) affected bacterial internalisation, whereas intracellular multiplication was inhibited by cytochalasins A, B, C, D and J (D being the most active) and by 2dG with a dose-response effect. The action of 2dG was counteracted by 50 mM glucose. Experiments carried out with cytochalasin D and a rhodamine-phalloidin conjugate showed the involvement of cytoskeletal elements in intracellular multiplication of Legionella; compounds acting on microtubules had no effect. 相似文献
1000.
Adriana Bochicchio Concetta Vazzana Serenella Puliga Alessandra Alberti Stefania Cinganelli Paolo Vernieri 《Plant Growth Regulation》1998,24(3):163-170
In our experimental conditions detached leaves of the resurrection plant Boea hygroscopica survived equilibration to 65–80% RH (Relative Humidity), but not to very low RH (close to 0%). The first aim of our research was to determine whether sensitivity to equilibration to very low RH depends on the rate of the drying process or on the very low final MC (Moisture Content) attained. The second aim of our research was to determine ABA content of leaves exposed to the two drying processes: a first step towards understanding whether ABA is involved in the tolerance mechanism of Boea hygroscopica.Detached leaves were equilibrated either to 1.4 or to 60–70% RH or to various temporal combinations of these two RH. ABA content was monitored during drying. Dehydrated leaves were imbibed in liquid water either directly or after a slow rehydration at 98% RH. Tolerance was assessed after 48 h imbibition in liquid water.The low final MC attained (about 3%) and not the rate of drying was responsible of the sensitivity of leaves equilibrated to 1.4% RH. Slow rehydration attained better recovery, but it was not able to allow full resurrection thus suggesting that a plain biophysical liquid-crystalline to gel phase transition of the membrane lipid bilayer could not fully account for the lethal damage of the very low MC.The conclusions relative to the first part of our research was of primary importance in interpreting results concerning ABA variations during the two drying treatments. ABA showed a very similar transient increase when excised leaves were dried at either 1.4% RH (sensitive leaves) or at 60–70% RH (tolerant leaves). However we cannot exclude that the transient increase of the hormone is a necessary component of the desiccation tolerance mechanisms in detached leaves of Boea hygroscopica: the extremely low MC reached by equilibration to 1.4% RH may impair the mechanism itself. 相似文献