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91.
Phenotypic characterization of DYT13 primary torsion dystonia.   总被引:3,自引:0,他引:3  
We describe the phenotype of DYT13 primary torsion dystonia (PTD) in a family first examined in 1994. A complete neurological evaluation was performed on all available family members: 8 individuals were definitely affected by dystonia. The family was re-evaluated in March 2000: at that time, 3 more individuals had developed symptoms of dystonia. Inheritance of PTD was autosomal dominant, with affected individuals spanning three consecutive generations and male-to-male transmission. Age at onset ranged from 5 to 43 years. Onset occurred either in the craniocervical region or in upper limbs. Progression was mild, and the disease course was benign in most affected individuals; generalization occurred only in 2 cases. We did not find anticipation of age at onset or of disease severity through generations. Most subjects presented with jerky, myoclonic-like dystonic movements of the neck or shoulders. DYT13-PTD is an autosomal dominant disease, with incomplete penetrance (58%). Clinical presentation and age at onset were more variable than in DYT1-PTD, and the neck was involved in most of those affected. Moreover, the individuals with generalised dystonia were not severely disabled and were able to lead independent lives. To date, this is the only family with DYT13-PTD.  相似文献   
92.
Protein tyrosine phosphatases play an essential role in the control of leucocyte cell growth an differentiation. Recently a new receptor type membrane tyrosine phosphatase named CD148 has been identified. This molecule is present on the membrane of all the hematopoietic lineages as well as on several other cell types, mainly epithelial cells and its expression increases after cell activation. This molecule is able to act as a transducing molecule. Moreover, CD148 is able to modulate the signal transduction through the TCR/CD3 complex, in a manner similar to CD45. It has also been suggested that CD148 could be involved in mechanisms of differentiation and inhibition of cell growth. In addition, CD148 seems to be associated with a serine/threonine kinase in certain epitelial cell lines and leucocytes. Here, we review recent data on the expression and function of CD148 in both human, mouse and rat.  相似文献   
93.
Expression and role of CCR6/CCL20 chemokine axis in pulmonary sarcoidosis   总被引:1,自引:0,他引:1  
We have shown previously that the chemokine receptors CXCR3 and CXCR6 are coexpressed by Th1 cells infiltrating the lung and the granuloma of patients with sarcoidosis. In this study, we evaluated the role of CCL20/CCR6 interaction in the pathogenesis of acute and chronic pulmonary sarcoidosis. By flow cytometry and molecular analyses, we have demonstrated that Th1 cells isolated from the bronchoalveolar lavage (BAL) of patients with sarcoidosis and T cell alveolitis are equipped with CCR6. Furthermore, CCR6(+) T cells coexpressed the chemokine receptors CXCR3 and CXCR6. Immunohistochemical analysis of lung specimens has shown that CCR6(+) T cells infiltrate lung interstitium and surround the central core of the granuloma. It is interesting that CCR6 was never detected on the alveolar macrophage (AM) surface, and it is observed in the cytoplasm of AMs from patients with sarcoidosis and alveolitis. The CCR6 ligand CCL20 was expressed by macrophages, multinucleated giant cells, and epithelioid cells infiltrating the granuloma. Furthermore, detectable levels of CCL20 protein are seen in the BAL fluid components of patients with active sarcoidosis, and sarcoid AMs release the CCR6 ligand in vitro. From a functional point of view, sarcoid Th1 cells were able to respond to CXCL10, CXCL16, and CCL20 in migratory assays. In vitro kinetic studies demonstrated that CCR6 is induced rapidly by IL-2, IL-18, and IFN-gamma. In conclusion, T cells expressing CCR6, CXCR3, and CXCR6 act coordinately with respective ligands and Th1 inflammatory cytokines in the alveolitic/granuloma phases of the disease.  相似文献   
94.
Glutamate exocytosis from astrocytes controls synaptic strength   总被引:7,自引:0,他引:7  
The release of transmitters from glia influences synaptic functions. The modalities and physiological functions of glial release are poorly understood. Here we show that glutamate exocytosis from astrocytes of the rat hippocampal dentate molecular layer enhances synaptic strength at excitatory synapses between perforant path afferents and granule cells. The effect is mediated by ifenprodil-sensitive NMDA ionotropic glutamate receptors and involves an increase of transmitter release at the synapse. Correspondingly, we identify NMDA receptor 2B subunits on the extrasynaptic portion of excitatory nerve terminals. The receptor distribution is spatially related to glutamate-containing synaptic-like microvesicles in the apposed astrocytic processes. This glial regulatory pathway is endogenously activated by neuronal activity-dependent stimulation of purinergic P2Y1 receptors on the astrocytes. Thus, we provide the first combined functional and ultrastructural evidence for a physiological control of synaptic activity via exocytosis of glutamate from astrocytes.  相似文献   
95.
The oral-facial-digital syndromes (OFDS) result from the pleiotropic effect of a morphogenetic impairment affecting almost invariably the mouth, face and digits. Other organ systems can be involved, defining specific types of OFDS. To date, 13 types have been distinguished based on characteristic clinical manifestations. An updated list of these types is provided and recent molecular data are discussed.  相似文献   
96.
97.
AXL is a tyrosine kinase receptor activated by GAS6 and regulates cancer cell proliferation migration and angiogenesis. We studied AXL as new therapeutic target in colorectal cancer (CRC). Expression and activation of AXL and GAS6 were evaluated in a panel of human CRC cell lines. AXL gene silencing or pharmacologic inhibition with foretinib suppressed proliferation, migration and survival in CRC cells. In an orthotopic colon model of human HCT116 CRC cells overexpressing AXL, foretinib treatment caused significant inhibition of tumour growth and peritoneal metastatic spreading. AXL and GAS6 overexpression by immunohistochemistry (IHC) were found in 76,7% and 73.5%, respectively, of 223 human CRC specimens, correlating with less differentiated histological grading. GAS6 overexpression was associated with nodes involvement and tumour stage. AXL gene was found amplified by Fluorescence in situ hybridization (FISH) in 8/146 cases (5,4%) of CRC samples.Taken together, AXL inhibition could represent a novel therapeutic approach in CRC.  相似文献   
98.
Determination of time since death is one of the most difficult and crucial issue in forensic medicine. Apart from body cooling, which is commonly used in the early postmortem interval (PMI), supravital reactions are the most interesting postmortem changes for time of death estimation. Nasal ciliary motility has been occasionally observed in postmortem period although no studies have focused on this phenomenon for forensic purposes. We aimed to evaluate the diagnostic usefulness of ciliary motility as a potential tool in estimating the time of death. Specimens of ciliated epithelium from 100 consecutive cadavers were obtained by scraping the nasal mucosa at three different postmortem intervals. The samples were then smeared on a slide, and an in vitro evaluation of ciliary movement was analyzed by phase-contrast microscopy. A postmortem nasal ciliary motility was observed, and a statistically significant relationship between decreasing ciliary movements and increasing postmortem interval was detected even in presence of putrefactive changes of nasal ultrastructure integrity. Some peculiar causes of death seem to influence ciliary motility in the early PMI, while no significant correlations with sex or age were observed. According to the results of this study, postmortem evaluation of nasal ciliary motility may be a bona fide and a feasible option for estimating the time of death.  相似文献   
99.
100.
Nitric Oxide Level Profile in Human Liver Transplantation   总被引:2,自引:0,他引:2  
The aim of this study was to monitor nitric oxide blood levels at various times intraoperatively and following liver transplantation in humans. Nitric oxide production was assessed directly as circulating nitrosyl-hemoglobin adducts by electron paramagnetic resonance spectroscopy in 22 patients undergoing orthotopic liver transplantation. Two significant peaks in nitrosyl-hemoglobin levels were detected at 5 and 60 min after reperfusion (5.02 ± 3.33 arbitrary units and 5.75 ± 4.19, respectively, vs 3.33 ± 2.28 under basal state; P < 0.05 for both comparisons). Postoperative nitrosyl-hemoglobin levels remained elevated, up to 5.42 ± 0.89 arbitrary units (P < 0.05 vs basal values). Neither soluble intercellular adhesion molecule- 1 or soluble endothelial-leukocyte adhesion molecule concentrations were altered intraoperatively. Only the former was significantly raised after transplantation. Neutrophil elastase levels showed an early increase and remained high throughout surgery, returning to basal values after transplantation. No correlations were found among studied parameters. These data suggest that nitric oxide may play a role in ischemia–reperfusion phases in human liver transplantation. Mechanisms other than leukocyte-endothelial adhesion and neutrophil activation seem to affect nitric oxide production under these conditions.  相似文献   
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