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11.
Lung transplant recipients are at high risk for herpes zoster and preventive measures are a significant unmet need. We investigated the safety and immunogenicity of two doses of a recombinant zoster vaccine (RZV) in lung transplant recipients (≥50 years). We enrolled 50 patients of which 49 received at least one vaccine dose. Anti-glycoprotein E (gE) antibody levels (n = 43) increased significantly compared to baseline (median optical density [OD] 1.96; interquartile range [IQR]: 1.17–2.89) after the first (median OD 3.41, IQR 2.54–3.81, p < .0001) and second vaccine dose (median OD 3.63, IQR 3.39–3.86, p < .0001). gE-specific polyfunctional CD4+ T cell frequencies (n = 38) also increased from baseline (median 85 per 106 CD4+ T cells; IQR: 46–180) to the first (median 128 per 106 CD4+ T cells; IQR: 82–353; p = .023) and after the second dose (median 361 per 106 CD4+ T cells; IQR: 146–848; p < .0001). Tenderness (83.0%; 95%CI: 69.2–92.4%) and redness (31.9%; 95%CI: 19.1–47.1%) at injection site were common. One rejection episode within 3 weeks of vaccination was observed. This is the first study demonstrating that RZV was safe and elicited significant humoral and cell-mediated immunity in lung transplant recipients. RZV is a new option for the prevention of shingles in this population.  相似文献   
12.
EBV-positive and EBV-negative posttransplant lymphoproliferative disorders (PTLDs) arise in different immunovirological contexts and might have distinct pathophysiologies. To examine this hypothesis, we conducted a multicentric prospective study with 56 EBV-positive and 39 EBV-negative PTLD patients of the K-VIROGREF cohort, recruited at PTLD diagnosis and before treatment (2013–2019), and compared them to PTLD-free Transplant Controls (TC, n = 21). We measured absolute lymphocyte counts (n = 108), analyzed NK- and T cell phenotypes (n = 49 and 94), and performed EBV-specific functional assays (n = 16 and 42) by multiparameter flow cytometry and ELISpot-IFNγ assays (n = 50). EBV-negative PTLD patients, NK cells overexpressed Tim-3; the 2-year progression-free survival (PFS) was poorer in patients with a CD4 lymphopenia (CD4+<300 cells/mm3, p <  .001). EBV-positive PTLD patients presented a profound NK-cell lymphopenia (median = 60 cells/mm3) and a high proportion of NK cells expressing PD-1 (vs. TC, p = .029) and apoptosis markers (vs. TC, p < .001). EBV-specific T cells of EBV-positive PTLD patients circulated in low proportions, showed immune exhaustion (p = .013 vs. TC) and poorly recognized the N-terminal portion of EBNA-3A viral protein. Altogether, this broad comparison of EBV-positive and EBV-negative PTLDs highlight distinct patterns of immunopathological mechanisms between these two diseases and provide new clues for immunotherapeutic strategies and PTLD prognosis.  相似文献   
13.
Thrombosis after liver transplantation substantially impairs graft- and patient survival. Inevitably, heritable disorders of coagulation originating in the donor liver are transmitted by transplantation. We hypothesized that genetic variants in donor thrombophilia genes are associated with increased risk of posttransplant thrombosis. We genotyped 775 donors for adult recipients and 310 donors for pediatric recipients transplanted between 1993 and 2018. We determined the association between known donor thrombophilia gene variants and recipient posttransplant thrombosis. In addition, we performed a genome-wide association study (GWAS) and meta-analyzed 1085 liver transplantations. In our donor cohort, known thrombosis risk loci were not associated with posttransplant thrombosis, suggesting that it is unnecessary to exclude liver donors based on thrombosis-susceptible polymorphisms. By performing a meta-GWAS from children and adults, we identified 280 variants in 55 loci at suggestive genetic significance threshold. Downstream prioritization strategies identified biologically plausible candidate genes, among which were AK4 (rs11208611-T, p = 4.22 × 10−05) which encodes a protein that regulates cellular ATP levels and concurrent activation of AMPK and mTOR, and RGS5 (rs10917696-C, p = 2.62 × 10−05) which is involved in vascular development. We provide evidence that common genetic variants in the donor, but not previously known thrombophilia-related variants, are associated with increased risk of thrombosis after liver transplantation.  相似文献   
14.
15.
cDNA arrays and proteomic analyses have allowed the rapid identification of specific genes and proteins implicated in multiple tumor types. These molecules must then be validated as clinically relevant prognostic and predictive markers, and this translational research is best conducted in the context of clinical trials. Outcomes data and clinical specimens collected in the ‘Arimidex’, Tamoxifen, Alone or in Combination (ATAC) study, for example, can now be used to compare the expression of biomarkers with clinical outcomes. In this study, adjuvant tamoxifen and anastrozole (‘Arimidex’) were compared alone and in combination in more than 9000 women with breast cancer. Anastrozole was found to be superior to tamoxifen in terms of disease-free survival, time to recurrence, and reduction in the incidence of contralateral tumors. Importantly, tissue specimens from surgical excision, local relapse, and contralateral breast cancer were collected and paraffin-embedded for storage. In the TA01 (TransATAC) program, these specimens will be studied (after obtaining patient consent) using tissue microarrays; tissue biopsy cores 0.6 mm in diameter will be removed from donor blocks and placed on recipient blocks, which will be sectioned to allow the simultaneous analysis of the same samples for multiple biomarkers. These analyses can help determine differential benefits of treatment with anastrozole or tamoxifen, depending on the expression of particular biomarkers in tumor cells. This research also should clarify de novo and acquired resistance mechanisms, and the validation of relevant molecular pathways could guide the development of new drugs. Ultimately, the TA01 program has the potential to favorably impact treatment choices for breast cancer. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
16.
ABSTRACT

Introduction: Drug discovery depends critically upon published results from the academy. The reproducibility of preclinical research findings reported by academia in the peer-reviewed literature has been called into question, seriously jeopardizing the value of academic science for inventing therapeutics.

Areas covered: The corrosive effects of the reproducibility issue on drug discovery are considered. Purported correctives imposed upon academia from the outside deal mainly with expunging fraudulent literature and imposing punitive sanctions on the responsible authors. The salutary influence of such post facto actions on the reproducibility of discovery-relevant preclinical research data from academia appears limited. Rather, intentional doctoral-scientist education focused on data replicability and translationally-meaningful science and active participation of university entities charged with research innovation and asset commercialization toward ensuring data quality are advocated as key academic initiatives for addressing the reproducibility issue.

Expert opinion: A mindset shift on the part of both senior university faculty and the academy to take responsibility for the data reproducibility crisis and commit proactively to positive educational, incentivization, and risk- and reward-sharing practices will be fundamental for improving the value of published preclinical academic research to drug discovery.  相似文献   
17.
Graft-versus-host disease after liver transplantation (LT-GVHD) is rare, frequently fatal, and associated with bone marrow failure (BMF), cytopenias, and hyperferritinemia. Given hyperferritinemia and cytopenias are present in hemophagocytic lymphohistiocytosis (HLH), and somatic mutations in hematopoietic cells are associated with hyperinflammatory responses (clonal hematopoiesis of indeterminate potential, CHIP), we identified the frequency of hemophagocytosis and CHIP mutations in LT-GVHD. We reviewed bone marrow aspirates and biopsies, quantified blood/marrow chimerism, and performed next-generation sequencing (NGS) with a targeted panel of genes relevant to myeloid malignancies, CHIP, and BMF. In all, 12 marrows were reviewed from 9 LT-GVHD patients. In all, 10 aspirates were evaluable for hemophagocytosis; 7 had adequate DNA for NGS. NGS was also performed on marrow from an LT cohort (n = 6) without GVHD. Nine of 10 aspirates in LT-GVHD patients showed increased hemophagocytosis. Five (71%) of 7 with LT-GVHD had DNMT3A mutations; only 1 of 6 in the non-GVHD LT cohort demonstrated DNMT3A mutation (p = .04). Only 1 LT-GVHD patient survived. BMF with HLH features was associated with poor hematopoietic recovery, and DNMT3A mutations were over-represented, in LT-GVHD patients. Identification of HLH features may guide prognosis and therapeutics. Further studies are needed to clarify the origin and impact of CHIP mutations on the hyperinflammatory state.

  相似文献   

18.
????Salivary gland tumor is one of the most common tumors in head and neck region with a great variety of morphology and biological behavior. Surgical operation is the major choice of salivary gland tumors. However?? except the benign and low-grade malignant tumors?? most salivary malignancies are in lack of specific treatment and the recurrent and metastic frequency is pretty high. Epigenetic study has become a hot spot of cancer research in recent years and one of widely studied field is the DNA promoter methylation. Our current article intends to discuss the possible application of DNA promoter methylation in the development??treatment and prognosis of salivary gland tumors.  相似文献   
19.
转化医学实验平台是突破基础研究与临床平台建设壁垒、将实际问题得以科学解决或转化为技术的依托。根据上海及国内其他地区转化医学建设发展的实际情况,针对目前大部分医院转化医学实验平台建设尚无统一模式、多学科交叉力度不大、资源分配不均等现状,探讨从战略定位、硬件建设、软件建设、人才队伍4个维度进行转化医学平台建设布局。基于提高科研设备使用效益、提高实验效率、保障安全性等共享目的,以需求为导向优化科研共享平台服务策略,从资源共享、服务共享、数据共享、特殊危险试剂共享等方面突出共享机制。实现院内医学转化多课题、多学科,甚至是跨院区、院内外、国际性合作平台的扩展。为优化资源配置、加强协同创新、样本库信息共享、托举人才培养、提高设备使用率、提升科研实际转化奠定基础。有利于基础科学研究转化成临床疗效的平台构建设置,有利于临床疗效转化成临床效果的平台实力展现,有利于临床效果转化成医疗保健措施的平台成果绽放。  相似文献   
20.
We describe a proteomics analysis to determine the molecular differences between normothermically perfused (normothermic machine perfusion, NMP) human kidneys with urine recirculation (URC) and urine replacement (UR). Proteins were extracted from 16 kidney biopsies with URC (n = 8 donors after brain death [DBD], n = 8 donors after circulatory death [DCD]) and three with UR (n = 2 DBD, n = 1 DCD), followed by quantitative analysis by mass spectrometry. Damage-associated molecular patterns (DAMPs) were decreased in kidney tissue after 6 hours NMP with URC, suggesting reduced inflammation. Vasoconstriction was also attenuated in kidneys with URC as angiotensinogen levels were reduced. Strikingly, kidneys became metabolically active during NMP, which could be enhanced and prolonged by URC. For instance, mitochondrial succinate dehydrogenase enzyme levels as well as carbonic anhydrase were enhanced with URC, contributing to pH stabilization. Levels of cytosolic and the mitochondrial phosphoenolpyruvate carboxykinase were elevated after 24 hours of NMP, more prevalent in DCD than DBD tissue. Key enzymes involved in glucose metabolism were also increased after 12 and 24 hours of NMP with URC, including mitochondrial malate dehydrogenase and glutamic-oxaloacetic transaminase, predominantly in DCD tissue. We conclude that NMP with URC permits prolonged preservation and revitalizes metabolism to possibly better cope with ischemia reperfusion injury in discarded kidneys.  相似文献   
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