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991.
Paola BendinelliPaola Maroni Emanuela Matteucci Maria Alfonsina Desiderio 《Biochimica et Biophysica Acta (BBA)/Molecular Cell Research》2011,1813(10):1767-1776
Metastatic cells switch between different modes of migration through supramolecular plasticity mechanism(s) still largely unknown. The aim of the present paper was to clarify some molecular aspects of the epigenetic control of migration of 1833-bone metastatic cells compared to MDA-MB231-parental mammary carcinoma cells. Active c-Src overexpression enhanced 1833-cell spontaneous migration and CXCR4-mediated chemoinvasion toward CXCL12 ligand. Only in metastatic cells, in fact, c-Src seemed to stabilize nuclear CXCR4-protein receptor possibly due to tyrosine phosphorylation, by impairing protein-degradative smear and causing instead an electrophoretic-mobility shift; the cytosolic steady-state level of CXCR4 was enhanced, and the protein appeared also phosphorylated. These findings suggested the triggering of unique signaling pathways in metastasis for homing of breast-cancer cells to congenial environment of specific organs. Microenvironmental stimuli activating c-Src might influence Ets1 binding to CXCR4 promoter and consequent transactivation, as well as CXCR4 post-translational regulatory mechanisms such as phosphorylation. Enhancement of Ets1 activity and CXCR4 induction by c-Src overexpression were prevented by histone deacetylase (HDAC) blockade. In contrast, HDAC inhibition with trichostatin A increased cytosolic phosphorylated CXCR4 expression in MDA-MB231 cells, but Ets1 involvement was practically unneeded. c-Src might be suggested as a bio-marker predicting metastasis sensitivity patterns to HDAC inhibitors. Rationally designed and individualized therapy may become possible as more is learned about the target molecules of HDAC's inhibitory agents and their roles, as undertaken for CXCR4 that is likely to be crucial for homing, angiogenesis and survival in a c-Src-dependent manner in bone-metastatic mammary cells. 相似文献
992.
Porro D Gasser B Fossati T Maurer M Branduardi P Sauer M Mattanovich D 《Applied microbiology and biotechnology》2011,89(4):939-948
Recombinant DNA (rDNA) technologies allow the production of a wide range of peptides, proteins and metabolites from naturally
non-producing cells. Since human insulin was the first heterologous compound produced in a laboratory in 1977, rDNA technology
has become one of the most important technologies developed in the 20th century. Recombinant protein and metabolites production
is a multi-billion dollar market. The development of a new product begins with the choice of the cell factory. The final application
of the compound dictates the main criteria that should be taken into consideration: (1) quality, (2) quantity, (3) yield and
(4) space time yield of the desired product. Quantity and quality are the most predominant requirements that must be considered
for the commercial production of a protein. Quantity and yield are the requirements for the production of a metabolite. Finally,
space time yield is crucial for any production process. It therefore becomes clear why the perfect host does not exist yet,
and why—despite important advances in rDNA applications in higher eukaryotic cells—microbial biodiversity continues to represent
a potential source of attractive cell factories. In this review, we compare the advantages and limitations of the principal
yeast and bacterial workhorse systems. 相似文献
993.
In the present study, we developed a rapid and efficient fluorescence in situ hybridization assay (FISH) in non-embedded tissues of the model plant Catharanthus roseus for co-localizing phytoplasmas and endophytic bacteria, opening new perspectives for studying the interaction between these microorganisms. 相似文献
994.
Marco Camardo Leggieri Neus Planas Pont Paola Battilani Naresh Magan 《Mycotoxin Research》2011,27(1):29-35
The aim of this work was to evaluate the potential use of qualitative volatile patterns produced by Penicillium nordicum to discriminate between ochratoxin A (OTA) producers and non-producer strains on a ham-based medium. Experiments were carried
out on a 3% ham medium at two water activities (aw ; 0.995, 0.95) inoculated with P. nordicum spores and incubated at 25°C for up to 14 days. Growing colonies were sampled after 1, 2, 3, 7 and 14 days, placed in 30-ml
vials, sealed and the head space analysed using a hybrid sensor electronic nose device. The effect of environmental conditions
on growth and OTA production was evaluated based on the qualitative response. However, after 7 days, it was possible to discriminate
between strains grown at 0.995 aw, and after 14 days, the OTA producer and non-producer strain and the controls could be discriminated at both aw levels. This study suggests that volatile patterns produced by P. nordicum strains may differ and be used to predict the presence of toxigenic contaminants in ham. This approach could be utilised
in ham production as part of a quality assurance system for preventing OTA contamination. 相似文献
995.
Scocco P Aralla M Catorci A Belardinelli C Arrighi S 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》2011,49(3):458-464
Mammalian aquaporins (AQPs) are a family of at least 13 integral membrane proteins expressed in various epithelia, where they function as channels to permeate water and small solutes. AQP5 is widely expressed in the exocrine gland where it is likely involved in providing an appropriate amount of fluid to be secreted with granular contents. As regards AQP5 expression in the salivary glands, literature is lacking concerning domestic animal species. This study was chiefly aimed at immunohistochemically investigating the presence and localization of AQP5 in sheep mandibular and parotid glands. In addition, AQP5 immunoreactivity was comparatively evaluated in animals fed with forage containing different amounts of water related to the pasture vegetative cycle, in order to shed light on the possible response of the gland to environmental modifications. Moderate AQP5-immunoreactivity was shown at the level of the lateral surface of mandibular serous demilune cells, not affected by the pasture vegetative cycle or water content. On the contrary, the parotid gland arcinar cells showed AQP5-immunoreactivity at the level of apical and lateral plasma membrane, which was slight to very strong, according to the pasture vegetative development and interannual climatic variations. AQP5 expression is likely due to its involvement in providing appropriate saliva fluidity. Indeed, the lowest AQP5 immunoreactivity was noticed when food water content increased. 相似文献
996.
Tripodi F Cirulli C Reghellin V Brambilla L Marin O Coccetti P 《Molecular and cellular biochemistry》2011,356(1-2):269-275
CK2 is a highly conserved protein kinase involved in different cellular processes, which shows a higher activity in actively proliferating mammalian cells and in various types of cancer and cancer cell lines. We recently demonstrated that CK2 activity is strongly influenced by growth rate in yeast cells as well. Here, we extend our previous findings and show that, in cells grown in either glucose or ethanol-supplemented media, CK2 presents no alteration in K(m) for both the ATP and the peptide substrate RRRADDSDDDDD, while a significant increase in V (max) is observed. In chemostat-grown cells, no difference of CK2 activity was observed in cells grown at the same dilution rate in media supplemented with either ethanol or glucose, excluding the contribution of carbon metabolism on CK2 activity. By using the eIF2β-derived peptide, which can be phosphorylated by the holoenzyme but not by the free catalytic subunits, we show that the holoenzyme activity requires the concurrent presence of both β and β' encoding genes. Finally, conditions of nitrogen deprivation leading to a G0-like arrest result in a decrease of total CK2 activity, but have no effect on the activity of the holoenzyme. These findings newly indicate a regulatory role of β and β' subunits of CK2 in the nutrient response. 相似文献
997.
Ravera S Aluigi MG Calzia D Ramoino P Morelli A Panfoli I 《Cellular and molecular neurobiology》2011,31(2):313-321
Extracellular ATP plays a pivotal role as a signaling molecule in physiological and pathological conditions in the CNS. In
several glioma cell lines, ATP is a positive factor for one or more characteristics important for the abnormal growth and
survival of these cells. This work presents immunofluorescence and biochemical analyses suggesting that an aerobic metabolism,
besides mitochondria, is located also on the plasma membrane of C6 glioma cells. An ATP synthesis coupled to oxygen consumption
was measured in plasma membrane isolated from C6 cells, sensitive to common inhibitors of respiratory chain complexes, suggesting
the involvement of a putative surface ATP synthase complex. Immunofluorescence imaging showed that Cytochrome c oxydase colocalized with WGA, a typical plasma membrane protein, on the plasma membrane of glioma cells. Cytochrome c oxydase staining pattern appeared punctuate, suggesting the intriguing possibility that the redox chains may be expressed
in discrete sites on C6 glioma cell membrane. Data suggest that the whole respiratory chain is localized on C6 glioma cell
surface. Moreover, when resveratrol, an ATP synthase inhibitor, was added to culture medium, a cytostatic effect was observed,
suggesting a correlation among the ectopic ATP synthesis and the tumor growth. So, a potential direction for the design of
new targets for future therapies may arise. 相似文献
998.
Daniela Basso Eliana Greco Andrea Padoan Paola Fogar Michele Scorzeto Elisa Fadi Dania Bozzato Stefania Moz Filippo Navaglia Carlo‐Federico Zambon Roberta Seraglia Eugenio De Carlo Anna Valerio Carlo Reggiani Sergio Pedrazzoli Mario Plebani 《Journal of cellular physiology》2011,226(2):456-468
After isolating NT‐S100A8 from pancreatic cancer (PC) tissue of diabetic patients, we verified whether this peptide alters PC cell growth and invasion and/or insulin release and [Ca2+]i oscillations of insulin secreting cells and/or insulin signaling. BxPC3, Capan1, MiaPaCa2, Panc1 (PC cell lines) cell growth, and invasion were assessed in the absence or presence of 50, 200, and 500 nM NT‐S100A8. In NT‐S100A8 stimulated β‐TC6 (insulinoma cell line) culture medium, insulin and [Ca2+] were measured at 2, 3, 5, 10, 15, 30, and 60 min, and [Ca2+]i oscillations were monitored (epifluorescence) for 3 min. Five hundred nanomolars NT‐S100A8 stimulated BxPC3 cell growth only and dose dependently reduced MiaPaCa2 and Panc1 invasion. Five hundred nanomolars NT‐S100A8 induced a rapid insulin release and enhanced β‐TC6 [Ca2+]i oscillations after both one (F = 6.05, P < 0.01) and 2 min (F = 7.42, P < 0.01). In the presence of NT‐S100A8, [Ca2+] in β‐TC6 culture medium significantly decreased with respect to control cells (F = 6.3, P < 0.01). NT‐S100A8 did not counteract insulin induced phosphorylation of the insulin receptor, Akt and IκB‐α, but it independently activated Akt and NF‐κB signaling in PC cells. In conclusion, NT‐S100A8 exerts a mild effect on PC cell growth, while it reduces PC cell invasion, possibly by Akt and NF‐κB signaling, NT‐S100A8 enhances [Ca2+]i oscillations and insulin release, probably by inducing Ca2+ influx from the extracellular space, but it does not interfere with insulin signaling. J. Cell. Physiol. 226: 456–468, 2011. © 2010 Wiley‐Liss, Inc. 相似文献
999.
Corallini F Celeghini C Rimondi E di Iasio MG Gonelli A Secchiero P Zauli G 《Journal of cellular physiology》2011,226(9):2279-2286
The soluble member of the TNF-R superfamily osteoprotegerin (OPG) is abundantly released under basal conditions by both mesenchymal stem cells (MSC) and fibroblasts and by endothelial cells upon stimulation with inflammatory cytokines. Since MSC, fibroblasts and endothelial cells represent key elements of the normal and tumor microenvironment and express detectable levels of surface TRAIL receptors, we investigated the effect of TRAIL on OPG release. Unexpectedly, recombinant TRAIL decreased the spontaneous OPG release in all cell types examined. Moreover, TRAIL decreased OPG release also in stromal cells co-cultured with lymphoma cells and counteracted the OPG induction by TN-alpha in HUVEC and MSC. Such down-regulation was not due to a masking effect in the ELISA quantification of the OPG released in the culture supernatants due to binding of OPG to its ligands (TRAIL and RANKL), as demonstrated by competition experiments with recombinant TRAIL and by the lack of RANKL release/induction. In addition, OPG down-regulation was not due to induction of cytotoxic effects by TRAIL, since the degree of apoptosis in response to TRAIL was negligible in all primary cell types. With regards to the possible molecular mechanism accounting for the down-regulation of OPG release by TRAIL, we found that treatment of MSC with TRAIL significantly decreased the phosphorylation levels of p38/MAPK. There is a suggestion that this pathway is involved in the stabilization of OPG mRNA. In this respect, the ability of TRAIL to decrease the release of OPG, in the absence of cell cytotoxicity, was mimicked by the p38/MAPK inhibitor SB203580. 相似文献
1000.
Role of excitatory amino acid transporter-2 (EAAT2) and glutamate in neurodegeneration: opportunities for developing novel therapeutics 总被引:1,自引:0,他引:1