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101.
Tetrafluoroborate salts of cationic ruthenium complexes [Ru(kappa(3)-tpy)(EPh(3))(2)Cl](+) (tpy=2,2':6',2'-terpyridine; E=P, 1 or As, 2) containing both the group 15 donor ligands and tpy and their representative substitution products are reported. Weak interaction {C-H...X (X=Cl, F and pi) and pi-pi interaction} studies revealed the presence of a double helical motif in complex 1, while the complex 2 assumes a single helical motif. Intercalative mode of interaction of the complexes 1 and 2 with calf thymus DNA (ctDNA) has been supported by absorption titration studies. 相似文献
102.
pTARGET [corrected] a new method for predicting protein subcellular localization in eukaryotes 总被引:2,自引:0,他引:2
MOTIVATION: There is a scarcity of efficient computational methods for predicting protein subcellular localization in eukaryotes. Currently available methods are inadequate for genome-scale predictions with several limitations. Here, we present a new prediction method, pTARGET that can predict proteins targeted to nine different subcellular locations in the eukaryotic animal species. RESULTS: The nine subcellular locations predicted by pTARGET include cytoplasm, endoplasmic reticulum, extracellular/secretory, golgi, lysosomes, mitochondria, nucleus, plasma membrane and peroxisomes. Predictions are based on the location-specific protein functional domains and the amino acid compositional differences across different subcellular locations. Overall, this method can predict 68-87% of the true positives at accuracy rates of 96-99%. Comparison of the prediction performance against PSORT showed that pTARGET prediction rates are higher by 11-60% in 6 of the 8 locations tested. Besides, the pTARGET method is robust enough for genome-scale prediction of protein subcellular localizations since, it does not rely on the presence of signal or target peptides. AVAILABILITY: A public web server based on the pTARGET method is accessible at the URL http://bioinformatics.albany.edu/~ptarget. Datasets used for developing pTARGET can be downloaded from this web server. Source code will be available on request from the corresponding author. 相似文献
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104.
Combs TP Nagajyothi Mukherjee S de Almeida CJ Jelicks LA Schubert W Lin Y Jayabalan DS Zhao D Braunstein VL Landskroner-Eiger S Cordero A Factor SM Weiss LM Lisanti MP Tanowitz HB Scherer PE 《The Journal of biological chemistry》2005,280(25):24085-24094
Adipose tissue plays an active role in normal metabolic homeostasis as well as in the development of human disease. Beyond its obvious role as a depot for triglycerides, adipose tissue controls energy expenditure through secretion of several factors. Little attention has been given to the role of adipocytes in the pathogenesis of Chagas disease and the associated metabolic alterations. Our previous studies have indicated that hyperglycemia significantly increases parasitemia and mortality in mice infected with Trypanosoma cruzi. We determined the consequences of adipocyte infection in vitro and in vivo. Cultured 3T3-L1 adipocytes can be infected with high efficiency. Electron micrographs of infected cells revealed a large number of intracellular parasites that cluster around lipid droplets. Furthermore, infected adipocytes exhibited changes in expression levels of a number of different adipocyte-specific or adipocyte-enriched proteins. The adipocyte is therefore an important target cell during acute Chagas disease. Infection of adipocytes by T. cruzi profoundly influences the pattern of adipokines. During chronic infection, adipocytes may represent an important long-term reservoir for parasites from which relapse of infection can occur. We have demonstrated that acute infection has a unique metabolic profile with a high degree of local inflammation in adipose tissue, hypoadiponectinemia, hypoglycemia, and hypoinsulinemia but with relatively normal glucose disposal during an oral glucose tolerance test. 相似文献
105.
106.
The anterior visceral endoderm-turning heads 总被引:2,自引:0,他引:2
Srinivas S 《Genesis (New York, N.Y. : 2000)》2006,44(11):565-572
The Anterior Visceral Endoderm is an extraembryonic tissue that plays a pivotal role during embryogenesis, being responsible for the proper orientation of the anterior-posterior axis of the embryo and for appropriate pattering of adjacent embryonic tissue. In this review I discuss the formation and migration of the AVE, and attempt to place some recent findings in the context of a working model. 相似文献
107.
108.
The pathogenesis underlying the selective degeneration of nigral dopaminergic neurons in Parkinson's disease is not fully understood but several lines of evidence implicate the role of oxidative stress and mitochondrial dysfunction. Depletion in levels of the thiol reducing agent glutathione (GSH + GSSG) is the earliest reported biochemical event to occur in the Parkinsonian substantia nigra prior to selective loss of complex I (CI) activity associated with the disease believed to contribute to subsequent dopaminergic cell death. Recent studies from our laboratory have demonstrated that acute reduction in both cellular and mitochondrial glutathione levels results in increased oxidative stress and a decrease in mitochondrial function linked to a selective decrease in CI activity through an NO-mediated mechanism (Jha, N.; Jurma, O.; Lalli, G.; Liu, Y.; Pettus, E. H.; Greenamyre, J. T.; Liu, R. M.; Forman, H. J.; Andersen, J. K. Glutathione depletion in PC12 results in selective inhibition of mitochondrial complex I activity. Implications for Parkinson's disease J. Biol. Chem. 275: 26096-26101; 2000. Hsu, M.; Srinivas, B.; Kumar, J.; Subramanian, R.; Andersen, J. Glutathione depletion resulting in selective mitochondrial complex I inhibition in dopaminergic cells is via an NO-mediated pathway not involving peroxynitrite: implications for Parkinson's disease J. Neurochem. 92: 1091-1103.2005.). However, the effect of prolonged glutathione depletion on dopaminergic cells is not known. In this present study, using low concentrations of buthionine-S-sulfoximine, a chemical inhibitor of the de novo glutathione synthesizing enzyme glutamate cysteine ligase, we developed a chronic model in which glutathione depletion in dopaminergic N27 cells for a 7-day period was found to lead to inhibition of CI activity via a peroxynitrite-mediated event which is reversible by the thiol reducing agent, dithiothreitol, and coincides with increased S-nitrosation of mitochondrial proteins. 相似文献
109.
Amino acid starvation induced autophagic cell death in PC-12 cells: Evidence for activation of caspase-3 but not calpain-1 总被引:2,自引:0,他引:2
Sadasivan S Waghray A Larner SF Dunn WA Hayes RL Wang KK 《Apoptosis : an international journal on programmed cell death》2006,11(9):1573-1582
While the apoptotic and necrotic cell death pathways have been well studied, there lacks a comprehensive understanding of
the molecular events involving autophagic cell death. We examined the potential roles of the apoptosis-linked caspase-3 and
the necrosis/apoptosis-linked calpain-1 after autophagy induction under prolonged amino acid (AA) starvation conditions in
PC-12 cells. Autophagy induction was observed as early as three hours following amino acid withdrawal. Cell death, measured
by lactate dehydrogenase (LDH) and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays occurred within
24 h following starvation and was accompanied by an upregulation in caspase-3 activity but not calpain-1. The cell death that
occurred following AA starvation was significantly alleviated by treatment with the autophagy inhibitor 3-methyl adenine but
not with the broad spectrum caspase inhibitors. Thus, this study demonstrates that 3-methyladenine-sensitive autophagic cell
death due to AA starvation in PC-12 cells is mechanistically and biochemically similar to, yet distinct from, classic caspase
dependent apoptosis.
Shankar Sadasivan and Anu Waghray have contributed equally to this work. 相似文献