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151.
CTGF and SMADs, maintenance of scleroderma phenotype is independent of SMAD signaling 总被引:31,自引:0,他引:31
Holmes A Abraham DJ Sa S Shiwen X Black CM Leask A 《The Journal of biological chemistry》2001,276(14):10594-10601
152.
The review discusses the current field status of human and bovine trypanosomiases, and focuses on the molecular basis of innate and acquired control of African trypanosomes in people, cattle, and Cape buffalo. 相似文献
153.
The K homology-type splicing regulatory protein, KSRP, activates splicing through intronic splicing enhancer sequences. It is highly expressed in neural cells and is required for the neural-specific splicing of the c-src N1 exon. In this study, we mapped the gene (gene symbols KHSRP and Khsrp) to human chromosome 19 by using radiation hybrid panels and to mouse chromosome 17 by studying an interspecific backcross panel. Human KHSRP is a positional candidate gene for familial febrile convulsion and Cayman type cerebellar ataxia. Comparative analysis of the human and mouse genomes indicates that the KHSRP gene is located in regions of conserved synteny between the two species. 相似文献
154.
In this review we discuss the activity of an ecologically significant group of psychrophilic bacteria, which are involved
in the hydrolysis of plant cell wall polymers. Until now these organisms have been largely overlooked, despite the key role
they play in releasing organic carbon fixed by primary producers in permanently cold environments such as Antarctica. This
review details a specific group of plant cell wall polymer-degrading enzymes known as β-glycanases. Studies on "cold" enzymes
in general are in their infancy, but it has been shown that many exhibit structural and functional modifications that enable
them to function at low temperature. β-Glycanases in particular are intriguing because their substrates (cellulose and xylan)
are very refractile, which may indicate that their "cold" modifications are pronounced. In addition, mesophilic β-glycanases
have been extensively studied and the current state of our knowledge is reviewed. This body of information can be exploited
to enable meaningful comparative studies between mesophilic and psychrophilic β-glycanases. The aim of such investigations
is to obtain a deeper insight into those structural and functional modifications that enable these enzymes to function at
low temperature and to examine the evolutionary relationship between mesophilic and psychrophilic β-glycanases.
Received: December 21, 1998 / Accepted: February 3, 1999 相似文献
155.
Neuronal precursor proliferation and axodendritic outgrowth have been traditionally regarded as discrete and sequential developmental stages. However, we recently found that sympathetic neuroblasts in vitro often elaborate long neuritic processes before dividing. Furthermore, these "paramitotic" neurites were maintained during cell division and neuritic morphology was consistently preserved by daughter cells after mitosis. This inheritance of neuritic morphology in vitro raised the possibility that proliferating neuroblasts engage in axodendritic outgrowth. To determine whether mitotic superior cervical ganglion (SCG) neuroblasts are engaged in pathfinding in vivo, we have combined retrograde axonal tracing of efferent nerve trunks with bromodeoxyuridine (BrdU) labeling of cells in S-phase. In fact, about 13% of BrdU(+) cells were retrogradely labeled, indicating that mitotic neuroblasts often have extraganglionic axonal projections. Moreover, the presence of axons during S-phase was observed at two developmental ages (E15.5 and E16. 5), implicating an ongoing function of paramitotic axons during neuronal ontogeny. Using a calculation to account for experimental limitations, we estimate that virtually all mitotic SCG neuroblasts have direct access to extraganglionic signals during development. We conclude that mitotic neuronal precursors in vivo engage in pathfinding, raising the possibility that interaction of proliferating populations with distant signals actively coordinates cell division and neural connectivity. 相似文献
156.
Identification of an NTF2-related factor that binds Ran-GTP and regulates nuclear protein export
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Black BE Lévesque L Holaska JM Wood TC Paschal BM 《Molecular and cellular biology》1999,19(12):8616-8624
Active transport of macromolecules between the nucleus and cytoplasm requires signals for import and export and their recognition by shuttling receptors. Each class of macromolecule is thought to have a distinct receptor that mediates the transport reaction. Assembly and disassembly reactions of receptor-substrate complexes are coordinated by Ran, a GTP-binding protein whose nucleotide state is regulated catalytically by effector proteins. Ran function is modulated in a noncatalytic fashion by NTF2, a protein that mediates nuclear import of Ran-GDP. Here we characterize a novel component of the Ran system that is 26% identical to NTF2, which based on its function we refer to as NTF2-related export protein 1 (NXT1). In contrast to NTF2, NXT1 preferentially binds Ran-GTP, and it colocalizes with the nuclear pore complex (NPC) in mammalian cells. These properties, together with the fact that NXT1 shuttles between the nucleus and the cytoplasm, suggest an active role in nuclear transport. Indeed, NXT1 stimulates nuclear protein export of the NES-containing protein PKI in vitro. The export function of NXT1 is blocked by the addition of leptomycin B, a compound that selectively inhibits the NES receptor Crm1. Thus, NXT1 regulates the Crm1-dependent export pathway through its direct interaction with Ran-GTP. 相似文献
157.
Black BE Vitto MJ Gioeli D Spencer A Afshar N Conaway MR Weber MJ Paschal BM 《Molecular endocrinology (Baltimore, Md.)》2004,18(4):834-850
Here we report that mutations within the DNA-binding domain of AR, shown previously to inhibit nuclear export to the cytoplasm, cause an androgen-dependent defect in intranuclear trafficking of AR. Mutation of two conserved phenylalanines within the DNA recognition helix (F582, 583A) results in androgen-dependent arrest of AR in multiple subnuclear foci. A point mutation in one of the conserved phenylalanines (DeltaF582, F582Y) is known to cause androgen insensitivity syndrome (AIS). Both AIS mutants (DeltaF582, F582Y) and the export mutant (F582, 583A) displayed androgen-dependent arrest in foci, and all three mutants promoted androgen-dependent accumulation of the histone acetyl transferase CREB binding protein (CBP) in the foci. The foci correspond to a subnuclear compartment that is highly enriched for the steroid receptor coactivator glucocorticoid receptor-interacting protein (GRIP)-1. Agonist-bound wild-type AR induces the redistribution of GRIP-1 from foci to the nucleoplasm. This likely reflects a direct interaction between these proteins because mutation of a conserved residue within the major coactivator binding site on AR (K720A) inhibits AR-dependent dissociation of GRIP-1 from foci. GRIP-1 also remains foci-associated in the presence of agonist-bound F582, 583A, DeltaF582, or F582Y forms of AR. Two-dimensional phospho-peptide mapping and analysis with a phospho-specific antibody revealed that mutant forms of AR that arrest in the subnuclear foci are hypophosphorylated at Ser81, a site that normally undergoes androgen-dependent phosphorylation. Our working model is that the subnuclear foci are sites where AR undergoes ligand-dependent engagement with GRIP-1 and CBP, a recruitment step that occurs before Ser81 phosphorylation and association with promoters of target genes. 相似文献
158.
159.
Smucny DA Allison DB Ingram DK Roth GS Kemnitz JW Kohama SG Lane MA Black A 《Journal of medical primatology》2004,33(1):48-54
The Primate Aging Database (PAD) is being developed to assist research using nonhuman primate models for various gerontological applications. We provide now an update of an earlier report providing data on hematological and blood chemistry values for rhesus monkeys across the adult lifespan. These data were collected from several research colonies and have been submitted to rigorous statistical analyses to identify relationships with chronological age. 相似文献
160.
Black J 《Bioscience reports》2004,24(4-5):302-322
This lecture outlines the early stages in the discovery of adrenaline β-receptor antagonists and of the histamine H2-receptor antagonists. It ends with a brief personal view about future research. 相似文献