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61.
Androgen-independent recurrence is the major limit of androgen ablation therapy for prostate cancer. Identification of alternative pathways promoting prostate tumor growth is thus needed. Stat5 has been recently shown to promote human prostate cancer cell survival/proliferation and to be associated with early prostate cancer recurrence. Stat5 is the main signaling pathway triggered by prolactin (PRL), a growth factor whose local production is also increased in high-grade prostate cancers. The first aim of this study was to use prostate-specific PRL transgenic mice to address the mechanisms by which local PRL induces prostate tumorogenesis. We report that (i) Stat5 is the major signaling cascade triggered by local PRL in the mouse dorsal prostate, (ii) this model recapitulates prostate tumorogenesis from precancer lesions to invasive carcinoma, and (iii) tumorogenesis involves dramatic accumulation and abnormal spreading of p63-positive basal cells, and of stem cell antigen-1–positive cells identified as a stem/progenitor-like subpopulation. Because basal epithelial stem cells are proposed to serve as tumor-initiating cells, we challenged the relevance of local PRL as a previously unexplored therapeutic target. Using a double-transgenic approach, we show that Δ1–9-G129R-hPRL, a competitive PRL-receptor antagonist, prevented early stages of prostate tumorogenesis by reducing or inhibiting Stat5 activation, cell proliferation, abnormal basal-cell pattern, and frequency or grade of intraepithelial neoplasia. This study identifies PRL receptor/Stat5 as a unique pathway, initiating prostate tumorogenesis by altering basal-/stem-like cell subpopulations, and strongly supports the importance of further developing strategies to target locally overexpressed PRL in human prostate cancer.  相似文献   
62.
We previously demonstrated that episodic autobiographical memories (EAMs) rely on a network of brain regions comprising the medial temporal lobe (MTL) and distributed neocortical regions regardless of their remoteness. The findings supported the model of memory consolidation, which proposes a permanent role of MTL during EAM retrieval (multiple‐trace theory or MTT) rather than a temporary role (standard model). Our present aim was to expand the results by examining the interactions between the MTL and neocortical regions (or MTL–neocortical links) during EAM retrieval with varying retention intervals. We used an experimental paradigm specially designed to engage aged participants in the recollection of EAMs, extracted from five different time‐periods, covering their whole life‐span, in order to examine correlations between activation in the MTL and neocortical regions. The nature of the memories was checked at debriefing by means of behavioral measures to control the degree of episodicity and properties of memories. Targeted correlational analyses carried out on the MTL, frontal, lateral temporal, and posterior regions revealed strong links between the MTL and neocortex during the retrieval of both recent and remote EAMs, challenging the standard model of memory consolidation and supporting MTT instead. Further confirmation was given by results showing that activation in the left and right hippocampi significantly correlated during the retrieval of both recent and remote memories. Correlations among extra‐MTL neocortical regions also emerged for all time‐periods, confirming the critical role of the prefrontal, temporal (lateral temporal cortex and temporal pole), precuneus, and posterior cingulate regions in EAM retrieval. Overall, this paper emphasizes the role of a bilateral network of MTL and neocortical areas whose activation correlate during the recollection of rich phenomenological recent and remote EAMs. © 2009 Wiley‐Liss, Inc.  相似文献   
63.
Abstract: The expression of human regulators of complement activation in endothelium of a transplanted organ is an approach to overcoming the complement (C)-mediated rejection of a xenograft. We designed a replication-deficient adenovirus (Ad) containing the human CD59 cDNA (AdCD59) in order to induce expression of human CD59 on xenogeneic endothelial cells (EC) and confer protection against human C-mediated lysis. In vitro transduction of rat EC with AdCD59 led to consistent levels of CD59 expression in all cells and significantly reduced EC lysis induced by human xenogeneic natural antibodies (XNA) binding and C activation. In addition, we analyzed whether Ad transduction had modified the phenotype of EC and the xenogeneic recognition of EC by human serum. For this, we first demonstrated that transduction of rat EC with AdCD59 or an Ad carrying the lacZ gene (AdlacZ) markedly enhanced the expression of some cell-membrane markers of EC activation, including class I MHC antigens and rat CD59, to levels comparable to those obtained with TNFα Up-regulation of class I MHC antigens was observed for both mRNA and protein expression. In contrast, AdCD59-mediated gene transfer slightly increase intercellular adhesion molecule-1 (ICAM-1) and did not modify the expression of Crry, a rat complement regulatory molecule. Second, we showed that these phenotypic modifications of EC did not affect the expression of the Galαl-3Gal epitope and the binding of human XNA. In addition, neither AdlacZ-mediated transduction, nor TNFα treatment, modified the sensitivity of xenogeneic EC to human serum-mediated lysis. In conclusion, this study demonstrated that transduction of human CD59 with an adenoviral vector conferred resistance to xenogeneic cultured EC against human C-mediated lysis but is associated with cellular activation of transduced EC. This finding may have important implications for the in vivo protocols and strategies intended to generate safer Ad vectors.  相似文献   
64.
Phenomenology, modus operandi of epistemological research in psychiatry is today rich of a great number of anthropological texts. Facing the XXIst century, it looks at its singular ability to criticize and to make links between natural sciences and human sciences so that it aims to raise the question of unity, while reconsidering the psychosomatic question, through a reaxamination of nosology.  相似文献   
65.
Measurement of heart rate variability (HRV) is a non-invasive technique that can be used to investigate the functioning of the autonomic nervous system, especially the balance between sympathetic and vagal activity. It has been proven to be very useful in humans for both research and clinical studies concerned with cardiovascular diseases, diabetic autonomic dysfunction, hypertension and psychiatric and psychological disorders. Over the past decade, HRV has been used increasingly in animal research to analyse changes in sympathovagal balance related to diseases, psychological and environmental stressors or individual characteristics such as temperament and coping strategies. This paper discusses current and past HRV research in farm animals. First, it describes how cardiac activity is regulated and the relationships between HRV, sympathovagal balance and stress and animal welfare. Then it proceeds to outline the types of equipment and methodological approaches that have been adapted and developed to measure inter-beats intervals (IBI) and estimate HRV in farm animals. Finally, it discusses experiments and conclusions derived from the measurement of HRV in pigs, cattle, horses, sheep, goats and poultry. Emphasis has been placed on deriving recommendations for future research investigating HRV, including approaches for measuring and analysing IBI data. Data from earlier research demonstrate that HRV is a promising approach for evaluating stress and emotional states in animals. It has the potential to contribute much to our understanding and assessment of the underlying neurophysiological processes of stress responses and different welfare states in farm animals.  相似文献   
66.
Helicobacter pylori is unique because of the unusually high number and diversity of its restriction modification (R-M) systems. HpyC1I R-M was recently characterized and contains an endonuclease which is an isoschizomer of the endonuclease BccI. This R-M is involved in adherence to gastric epithelial cells, a crucial step in bacterial pathogenesis. This observation illustrates the fact that R-M systems have other putative biological functions in addition to protecting the bacterial genome from external DNA. The genomic diversity of HpyC1I R-M was evaluated more precisely on a large collection of H. pylori strains by PCR, susceptibility to BccI digestion and sequencing. The results obtained support the mechanism of gain and loss of this R-M system in the H. pylori genome, and suggest that it is an ancestral system which gradually disappears during H. pylori evolution, following successive steps: (1) inactivation of the endonuclease gene, followed or accompanied by: (2) inactivation of the methyltransferase genes, and then: (3) definitive loss, leaving only short endonuclease remnant sequences.  相似文献   
67.
Using a combination of molecular cytogenetic and large-scale expression analysis in human T-cell acute lymphoblastic leukemias (T-ALLs), we identified and characterized a new recurrent chromosomal translocation, targeting the major homeobox gene cluster HOXA and the TCRB locus. Real-time quantitative polymerase chain reaction (RQ-PCR) analysis showed that the expression of the whole HOXA gene cluster was dramatically dysregulated in the HOXA-rearranged cases, and also in MLL and CALM-AF10-related T-ALL cases, strongly suggesting that HOXA genes are oncogenic in these leukemias. Inclusion of HOXA-translocated cases in a general molecular portrait of 92 T-ALLs based on large-scale expression analysis shows that this rearrangement defines a new homogeneous subgroup, which shares common biologic networks with the TLX1- and TLX3-related cases. Because T-ALLs derive from T-cell progenitors, expression profiles of the distinct T-ALL subgroups were analyzed with respect to those of normal human thymic subpopulations. Inappropriate use or perturbation of specific molecular networks involved in thymic differentiation was detected. Moreover, we found a significant association between T-ALL oncogenic subgroups and ectopic expression of a limited set of genes, including several developmental genes, namely HOXA, TLX1, TLX3, NKX3-1, SIX6, and TFAP2C. These data strongly support the view that the abnormal expression of developmental genes, including the prototypical homeobox genes HOXA, is critical in T-ALL oncogenesis.  相似文献   
68.
69.
ABSTRACT: Introduction: Assessment of muscle mechanical properties may provide clinically valuable information for follow‐up of patients with Duchenne muscular dystrophy (DMD) through the course of their disease. In this study we aimed to assess the effect of DMD on stiffness of relaxed muscles using elastography (supersonic shear imaging). Methods: Fourteen DMD patients and 13 control subjects were studied. Six muscles were measured at 2 muscle lengths (shortened and stretched): gastrocnemius medialis (GM); tibialis anterior (TA); vastus lateralis (VL); biceps brachii (BB); triceps brachii (TB); and abductor digiti minimi (ADM). Results: Stiffness was significantly higher in DMD patients compared with controls for all the muscles (main effect for population, P < 0.033 in all cases), except for ADM. The effect size was small (d = 0.33 for ADM at both muscle lengths) to large (d = 0.86 for BB/stretched). Conclusions: Supersonic shear imaging is a sensitive non‐invasive technique to assess the increase in muscle stiffness associated with DMD. Muscle Nerve 51 : 284–286, 2015  相似文献   
70.
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