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1.
Isolated patellofemoral arthritis is an increasingly recognized entity, and is usually associated with previous patellofemoral dysplasia or instability. Patellofemoral arthroplasty (PFA) has evolved significantly in recent years, both in terms of implant design and importantly in the understanding of appropriate patient selection. This review outlines the indications and investigations for PFA, provides a brief history of the development of contemporary implants, and presents the clinical outcomes for the prostheses most commonly used in the UK. In addition, it provides a detailed surgical technique for implantation of an onlay implant, with tips on how to optimize patellofemoral biomechanics and thus achieve a consistently good outcome. 相似文献
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Sonoelasticity imaging of prostate cancer: in vitro results 总被引:2,自引:0,他引:2
4.
Characterization of gp 50, a major glycoprotein present in rat brain synaptic membranes, with a monoclonal antibody 总被引:4,自引:0,他引:4
Philip W. Beesley Toni Paladino Claude Gravel Richard A. Hawkes James W. Gurd 《Brain research》1987,408(1-2):65-78
Several cell lines secreting monoclonal antibodies (Mabs) against a major forebrain synaptic membrane (SM) glycoprotein, gp 50, have been raised. Western blots show that the Mabs react with a polypeptide doublet of Mrs 49 and 45 kDa. These polypeptides exist solely in a concanavalin A (Con A) binding form. Removal of the Con A receptors by digestion with endo-beta-N-acetylglucosaminidase H (endo H) lowers the Mrs of the glycoprotein doublet to 36.5 and 34 kDa. Western blots of 2D polyacrylamide gels indicate that gp 50 exists in several isoforms. Solid phase radioimmunoassay (RIA) and Western blots of brain subcellular fractions show the antigenic material to be concentrated in the SM fraction, but to be present in much lower amounts in synaptic junctions and postsynaptic densities. Gp 50 appears to be brain specific. Regional distribution studies show that it is present in all brain regions but is two-fold concentrated in cerebellum, brainstem and midbrain compared to forebrain. Immunocytochemical studies of several brain regions show that gp 50-like immunoreactivity is neuron specific and is concentrated in selected neuronal species, particularly granule cells. In both cerebellar and hippocampal granule cells gp 50-like immunoreactivity is localized in the perikarya and primary dendrites. Though immunocytochemistry did not show staining of synaptic regions this may be due to masking of the reactive epitope. The results are discussed in terms of the molecular properties of gp 50 and its subcellular localization in brain tissue. 相似文献
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The insulin-like growth factor-II/mannose-6-phosphate receptor: structure, distribution and function in the central nervous system 总被引:4,自引:0,他引:4
The insulin-like growth factor-II/mannose-6-phosphate (IGF-II/M6P) receptor is a multifunctional single transmembrane glycoprotein which, along with the cation-dependent M6P (CD-M6P) receptor, mediates the trafficking of M6P-containing lysosomal enzymes from the trans-Golgi network (TGN) to lysosomes. Cell surface IGF-II/M6P receptors also function in the degradation of the non-glycosylated IGF-II polypeptide hormone, as well as in the capture and activation/degradation of extracellular M6P-bearing ligands. In recent years, the multifaceted role of the receptor has become apparent, as several lines of evidence have indicated that in addition to its role in lysosomal enzyme trafficking, clearance and/or activation of a variety of growth factors and endocytosis-mediated degradation of IGF-II, the IGF-II/M6P receptor may also mediate transmembrane signal transduction in response to IGF-II binding under certain conditions. However, very little is known about the physiological significance of the receptor in the function of the central nervous system (CNS). This review aims to delineate what is currently known about IGF-II/M6P receptor structure, its ligand binding properties and role in lysosomal enzyme transport. It also summarizes the recent data regarding the role of the receptor in the CNS, including its distribution, possible importance for normal and activity-dependent functioning as well as its implications in neurodegenerative disorders such as Alzheimer's disease (AD). 相似文献
9.
Summary Patients with insulin-dependent diabetes mellitus (IDDM) possess antibodies to the cytoplasmic domains of two closely related
tyrosine phosphatase-like proteins, IA-2 and phogrin, previously detected as 40 kDa and 37 kDa tryptic fragments, respectively.
A higher proportion of IDDM patients possess antibodies to IA-2 than to phogrin, and autoimmunity to phogrin might arise through
cross-reactivity with the highly homologous IA-2. In this study, we have investigated the major regions of IA-2 recognized
by antibodies in IDDM patients and examined the ability of phogrin to block antibody binding to these regions as a measure
of cross-reactivity. Analysis of antibody binding to in vitro transcribed and translated polypeptides representing different
regions of the cytoplasmic domain of IA-2 identified five different patterns of reactivity with antibodies in IDDM. Protein
footprinting analysis, whereby polypeptide fragments generated on protease treatment of immune complexes are studied, indicated
considerable heterogeneity in antibody recognition of IA-2, even between sera with similar reactivity to deletion mutants.
Blocking studies with recombinant phogrin indicated that IA-2 antibodies recognize epitopes that are both unique to IA-2 and
shared with phogrin. The amino-terminal 150 amino acids of the cytoplasmic domain of IA-2 encompass epitopes that are not
represented on phogrin, whereas shared epitopes are localized within the carboxy-terminal 220 amino acids. The results demonstrate
considerable heterogeneity between IDDM patients in autoantibody recognition of IA-2 in IDDM, whereas antibody recognition
of phogrin is restricted in most patients to epitopes also present on IA-2. [Diabetologia (1997) 40: 1327–1333]
Received: 4 April 1997 and in revised form: 2 July 1997 相似文献
10.
MAP1a is a microtubule-associated protein with an apparent molecular weight of 360 kDa that is found in the axonal and dendritic processes of neurons. Two monoclonal anti-MAP1a antibodies, anti-A and anti-BW6, revealed different epitope distributions in the adult mouse cerebellum. Anti-A stained Purkinje and granule cells uniformly throughout the cerebellum. In contrast, anti-BW6 selectively stained the dendrites of a subset of Purkinje cells, revealing parasagittal bands of immunoreactivity in the molecular layer. The compartmentation of the BW6 epitope was compared to the Purkinje cells as revealed by immunostaining with anti-zebrin II, a well known antigen expressed selectively by bands of Purkinje cells. The anti-BW6 staining pattern was complementary to the zebrin II bands, the zebrin II- Purkinje cells having BW6+ dendrites. These results demonstrate that MAP1a is present in two forms in the mouse cerebellum, one of which is segregated into parasagittal bands. This may indicate a unique MAP1a isoform or may reflect differences in the metabolic states of Purkinje cell classes, and regional differences in their functions. 相似文献