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Chen XS  Yin YP 《The Lancet infectious diseases》2012,12(4):269; author reply 270-269; author reply 271
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Objective SET8 is a member of the SET domain-containing family and the only known lysine methyltransferase(KMT) that monomethylates lysine 20 of histone H4(H4 K20 me1). SET8 has been implicated in many essential cellular processes, including cell cycle regulation, DNA replication, DNA damage response, and carcinogenesis. There is no conclusive evidence, however, regarding the effect of SET8 on radiotherapy. In the current study we determined the efficacy of SET8 inhibition on radiotherapy of tum...  相似文献   
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Interleukin 10 (IL-10)-producing regulatory B-cells (Bregs) suppress inflammatory responses that mediate autoimmune diseases. However, it is unknown whether Bregs derive from a pre-existing dedicated B-cell lineage or if any B-cell can differentiate into Bregs in response to BCR or TLR activation. GL7+ B-cells are antigen-experienced differentiated B-cells while GL7−/lo are at an early stage of B-cell differentiation. While both GL7−/lo and GL7+ B cells can produce IL-10, differentiation of GL7 B-cells into Bregs does not require CD19- or Bcl6-induced signals, suggesting that BCR-induced proliferation or Ig class-switching is not necessary for generation of Breg cells. Of particular importance, we show that GL7 Breg cells are dramatically expanded in lupus-like mice and GL7 Bregs suppressed inflammatory responses in lupus-like mice by inducing expansion of Foxp3+Treg cells. Taken together, these results suggest that pre-existing GL7IL-10+ cells are expanded during inflammation, differentiate into GL7+ Bregs and contribute to immune-regulation in lupus-like mice.  相似文献   
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ObjectiveTo evaluate cell-free DNA (cfDNA) in plasma as a promising biomarker for lymphoma, altered levels of cfDNA and its association with clinical parameters are investigated in patients suffered from lymphomas.MethodsPeripheral blood specimens were collected from 60 patients with lymphoma during initial diagnosis and those of another 107 patients with lymphoma during treated stage were also collected, 93 healthy volunteers were selected as control group. Quantitative PCR was used to detect cfDNA level in each group, cfDNA level in different groups was analyzed to understand its relationship with lymphoma patients' clinical features. After correlation analysis between cfDNA and clinical characteristics, Receiver operator characteristic curve was performed to analyze sensitivity and specificity of cfDNA and LDH.ResultscfDNA concentration and integrity in initial stage of lymphoma patients were significantly higher than those in treated stage, and cfDNA concentration in treated phase was significantly higher than cfDNA concentration in control group. There was no significant difference in cfDNA integrity at treated stage compared with control group. There was no significant correlation between patient's age, gender, extranodal invasion and lymphoma pathological type and cfDNA concentration and integrity; In contrast, there was a significant correlation between ECOG score, LDH content, Ann Arbor stage, IPI, B-symptoms, Ki-67 expression and radiotherapy and cfDNA concentration and integrity, both at the time of initial diagnosis and treated stage. cfDNA concentration detection is an optimal diagnostic indicator, followed by cfDNA integrity detection, the sensitivity and specificity of both are superior to the traditional LDH detection.ConclusioncfDNA level is significantly increased in lymphomas patient plasma and may help lymphoma screening. cfDNA level may serve as a potential indicator of lymphomas treatment efficacy.  相似文献   
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Endothelium damage caused by Treponema pallidum is the key step in the systemic dissemination and pathophysiology of syphilis, particularly cardiovascular syphilis and neurosyphilis. However, the molecular mechanisms supporting endothelium damage of syphilis are undefined. The outer membrane proteins were thought to be involved. Tp92 was first identified as an outer membrane protein of T. pallidum. Homologous proteins to Tp92 play important roles in cell attachment, inflammation, and tissue destruction in other bacterial species. In this study, we investigated the effect of Tp92 on endothelial cells activation. The data showed that Tp92 induced chemerin production in activated endothelial cells. Endothelial cell-derived chemerin upregulated the expression of TNF-α and ICAM-1 in endothelial cells via CMKLR1. In addition, endothelial cell-derived chemerin promoted THP-1-derived macrophage migration towards endothelial cells. These findings suggest that Tp92 may play an important role in mediating endothelial cell activation by inducing the secretion of chemerin.  相似文献   
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Triple negative breast cancer (TNBC) is an aggressive subtype of breast cancer that currently lacks effective biomarkers and therapeutic targets required to investigate the diagnosis and treatment of TNBC. Here we performed a comprehensive differential analysis of 165 TNBC samples by integrating RNA-seq data of breast tumor tissues and adjacent normal tissues from both our cohort and The Cancer Genome Atlas (TCGA). Pathway enrichment analysis was conducted to evaluate the biological function of TNBC-specific expressed genes. Further multivariate Cox proportional hazard regression was performed to evaluate the effect of these genes on TNBC prognosis. In this report, we identified a total of 148 TNBC-specific expressed genes that were primarily enriched in mammary gland morphogenesis and hormone levels related pathways, suggesting that mammary gland morphogenesis might play a unique role in TNBC patients differing from other breast cancer types. Further survival analysis revealed that nine genes (FSIP1, ADCY5, FSD1, HMSD, CMTM5, AFF3, CYP2A7, ATP1A2, and C11orf86) were significantly associated with the prognosis of TNBC patients, while three of them (ADCY5, CYP2A7, and ATP1A2) were involved in the hormone-related pathways. These findings indicated the vital role of the hormone-related genes in TNBC tumorigenesis and may provide some independent prognostic markers as well as novel therapeutic targets for TNBC.  相似文献   
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BackgroundMinimally-invasive methods to treat scars address a common pathway of altering collagen structure, leading to collagen remodeling.ObjectiveIn this study, we employed in situ redox chemistry to create focal pH gradients in skin, altering dermal collagen, in a process we refer to as electrochemical therapy (ECT). The effects of ECT to induce biochemical and structural changes in ex vivo porcine skin were examined.MethodsDuring ECT, two platinum electrodes were inserted into fresh porcine skin, and following saline injection, an electrical potential was applied. pH mapping, high frequency ultrasonography, and two photon excitation microscopy and second harmonic generation (SHG) microscopy were used to evaluate treatment effects. Findings were correlated with histology.ResultsFollowing ECT, pH mapping depicted acid and base production at anode and cathode sites respectively, with increasing voltage and application time. Gas formation during ECT was observed with ultrasonography. Anode sites showed significant loss of SHG signal, while cathode sites showed disorganized collagen structure with fewer fibrils emitting an attainable signal. Histologically, collagen denaturation at both sites was confirmed.ConclusionWe demonstrated the production of in situ acid and base in skin occurring via ECT. The effects chemically and precisely alter collagen structure through denaturation, giving insight on the potential of ECT as a simple, low-cost, and minimally-invasive means to remodel skin and treat scars.  相似文献   
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