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41.
The aim of the study was to evaluate the long-term survival of patients with invasive lobular carcinomas (ILC) and invasive ductal carcinomas (IDC) and the metastatic behavior of these two disease entities. Originally, all consecutive patients with pure lobular invasive breast cancers diagnosed between 1990 and 1999 in the area served by the Tampere University Hospital and their matched IDC controls were identified and re-evaluated histopathologically in this follow-up study, resulting in a total of 243 ILCs and 243 IDCs. Data on recurrences and survival were collected until the end of year 2009. Statistical analyses including Kaplan–Meier method, log-rank test, Fisher's exact test and Cox regression analysis were performed with the PASW Statistics 18.0 computer program. P-values of <0.05 were considered statistically significant.Within the mean follow-up time of 10.04 years, locoregional recurrences were significantly more common among the ILCs than IDCs (35 vs. 20, p = 0.04), but no differences in the total number of distant recurrences or bilaterality were observed. However, when the first distant recurrence sites were studied, ILC patients had significantly less lung metastases (p = 0.04), but more skin metastases (p = 0.04). During the whole follow-up period IDCs metastasized significantly more frequently to the lungs (p = 0.002), whereas gastrointestinal metastases were more common among ILCs (p = 0.02). Although the known favorable prognostic factors (hormone receptor positivity, low grade, low s-phase) were more common for the ILCs, the disease-free survival, the overall survival and the survival after recurrence did not differ between the groups. However, the Cox-regression model showed significantly worse survival for ILCs after adjusting for age, TNM-status, grade and ER-positivity (p = 0.004).In conclusion, ILC and IDC differ in respect for visceral metastases. Despite the known favorable prognostic factors and originally favorable survival, patients with lobular histology appear to have a worse survival in the multivariate analysis after a prolonged follow-up.  相似文献   
42.
背景与目的 乳腺癌是全球女性发病率最高的恶性肿瘤,化疗是乳腺癌最重要的治疗方式之一,最近的研究表明,化疗可能通过增强肿瘤微环境中的抗肿瘤免疫力来发挥抗肿瘤效应。因此,本研究通过生物信息学分析明确乳腺癌患者新辅助化疗(NAC)前后肿瘤相关巨噬细胞(TAMs)及相关基因的变化,评估NAC对乳腺癌患者免疫影响。方法 GEO数据库输入“Breast Cancer”,“TAMs”,“Chemotherapy”进行检索,选择人乳腺癌组织的GSE134600数据集进行分析。通过R包(limma函数)筛选乳腺癌患者NAC前后组织样本中差异表达基因(DEGs)。对所有DEGs进行GO功能富集和KEGG通路分析。通过Cytoscape软件对DEGs进行蛋白互作网络可视化,并筛选关键核心基因,通过cBioPortal对10个关键基因进行突变分析。使用R包(CIBERSORT)对GSE134600数据中的免疫细胞分布及相关性进行评估。结果 鉴定出751个乳腺癌NAC前后DEGs(409个上调基因和342个下调基因)。通过GO富集分析DEGs的生物过程(BP)、细胞组分(CC)和分子功能(MF)。在BP中主要富集在I型干扰素(IFN-I)信号通路/病毒应答与防御和病毒生命周期方面;在CC中主要富集在细胞膜的外在成分和细胞膜的细胞质侧方面;在MF中主要富集在细胞因子受体结合、双链RNA结合和脂肽结合方面。KEGG通路富集分析中,DEGs主要富集在甲型H1N1流感、麻疹、丙型肝炎、冠状病毒病COVID-19、NF-κB信号通路、EBV病毒感染、NOD样受体信号通路和阿米巴病信号通路。通过CytoHubba插件筛选出乳腺癌NAC前后TAMs相互作用程度最高的前10个关键基因:IFIT1、ISG15、MX1、MX2、IRF7、RSAD2、IFIT3、IFI35、IFI6、IFITM1。多组学分析发现IFIT1、MX1和MX2主要发生缺失突变,IFIT1主要发生基因深度删除,而MX1和MX2主要发生基因扩增。NAC后乳腺癌组织中M0巨噬细胞、CD8+T细胞及M2巨噬细胞含量减少,M0巨噬细胞与记忆性B细胞成正相关(r=0.64),与未活化的CD4+记忆性T细胞呈负相关(r=-0.66)。结论 所发现的乳腺癌患者NAC前后TAMs相关的DEGs与干扰素信号通路密切相关,提示干扰素信号通路在NAC可能通过改变TAMs而发挥重要作用。同时NAC前后M0巨噬细胞发生明显改变,提示化疗可能通过改变M0巨噬细胞分布及免疫功能调节对肿瘤的免疫应答。  相似文献   
43.
The concept of moderate consumption of ethanol (beverage alcohol) has evolved over time from considering this level of intake to be nonintoxicating and noninjurious, to encompassing levels defined as “statistically” normal in particular populations, and the public health-driven concepts that define moderate drinking as the level corresponding to the lowest overall rate of morbidity or mortality in a population. The various approaches to defining moderate consumption of ethanol provide for a range of intakes that can result in blood ethanol concentrations ranging from 5 to 6 mg/dl, to levels of over 90 mg/dl (i.e., 20 mM). This review summarizes available information regarding the effects of moderate consumption of ethanol on the adult and the developing nervous systems. The metabolism of ethanol in the human is reviewed to allow for proper appreciation of the important variables that interact to influence the level of exposure of the brain to ethanol once ethanol is orally consumed. At the neurochemical level, the moderate consumption of ethanol selectively affects the function of GABA, glutamatergic, serotonergic, dopaminergic, cholinergic, and opioid neuronal systems. Ethanol can affect these systems directly, and/or the interactions between and among these systems become important in the expression of ethanol's actions. The behavioral consequences of ethanol's actions on brain neurochemistry, and the neurochemical effects themselves, are very much dose- and time-related, and the collage of ethanol's actions can change significantly even on the rising and falling phases of the blood ethanol curve. The behavioral effects of moderate ethanol intake can encompass events that the human or other animal can perceive as reinforcing through either positive (e.g., pleasurable, activating) or negative (e.g., anxiolysis, stress reduction) reinforcement mechanisms. Genetic factors and gender play an important role in the metabolism and behavioral actions of ethanol, and doses of ethanol producing pleasurable feelings, activation, and reduction of anxiety in some humans/animals can have aversive, sedative, or no effect in others. Research on the cognitive effects of acute and chronic moderate intake of ethanol is reviewed, and although a number of studies have noted a measurable diminution in neuropsychologic parameters in habitual consumers of moderate amounts of ethanol, others have not found such changes. Recent studies have also noted some positive effects of moderate ethanol consumption on cognitive performance in the aging human. The moderate consumption of ethanol by pregnant women can have significant consequences on the developing nervous system of the fetus. Consumption of ethanol during pregnancy at levels considered to be in the moderate range can generate fetal alcohol effects (behavioral, cognitive anomalies) in the offspring. A number of factors–including gestational period, the periodicity of the mother's drinking, genetic factors, etc.–play important roles in determining the effect of ethanol on the developing central nervous system. A series of recommendations for future research endeavors, at all levels, is included with this review as part of the assessment of the effects of moderate ethanol consumption on the central nervous system  相似文献   
44.
45.
Chronic kidney disease (CKD) imposes a strong and independent risk for peripheral artery disease (PAD). While solutes retained in CKD patients (uremic solutes) inflict vascular damage, their role in PAD remains elusive. Here, we show that the dietary tryptophan-derived uremic solutes including indoxyl sulfate (IS) and kynurenine (Kyn) at concentrations corresponding to those in CKD patients suppress β-catenin in several cell types, including microvascular endothelial cells (ECs), inhibiting Wnt activity and proangiogenic Wnt targets in ECs. Mechanistic probing revealed that these uremic solutes downregulated β-catenin in a manner dependent on serine 33 in its degron motif and through the aryl hydrocarbon receptor (AHR). Hindlimb ischemia in adenine-induced CKD and IS solute–specific mouse models showed diminished β-catenin and VEGF-A in the capillaries and reduced capillary density, which correlated inversely with blood levels of IS and Kyn and AHR activity in ECs. An AHR inhibitor treatment normalized postischemic angiogenic response in CKD mice to a non-CKD level. In a prospective cohort of PAD patients, plasma levels of tryptophan metabolites and plasma’s AHR-inducing activity in ECs significantly increased the risk of future adverse limb events. This work uncovers the tryptophan metabolite/AHR/β-catenin axis as a mediator of microvascular rarefaction in CKD patients and demonstrates its targetability for PAD in CKD models.  相似文献   
46.
通过文献资料法对Ⅱ型糖尿病的发病机理及Ⅱ型糖尿病运动疗法进行生物学分析,剖析运动对Ⅱ型糖尿病胰岛素的敏感性、加速脂肪分解及降低血脂和控制肥胖、改善心肺功能的生物学作用,为Ⅱ型糖尿病的运动疗法提供理论指导。  相似文献   
47.
Patients with heart failure (HF) have augmented vascular tone, which increases cardiac workload, impairing ventricular output and promoting further myocardial dysfunction. The molecular mechanisms underlying the maladaptive vascular responses observed in HF are not fully understood. Vascular smooth muscle cells (VSMCs) control vasoconstriction via a Ca2+-dependent process, in which the type 1 inositol 1,4,5-trisphosphate receptor (IP3R1) on the sarcoplasmic reticulum (SR) plays a major role. To dissect the mechanistic contribution of intracellular Ca2+ release to the increased vascular tone observed in HF, we analyzed the remodeling of IP3R1 in aortic tissues from patients with HF and from controls. VSMC IP3R1 channels from patients with HF and HF mice were hyperphosphorylated by both serine and tyrosine kinases. VSMCs isolated from IP3R1VSMC–/– mice exhibited blunted Ca2+ responses to angiotensin II (ATII) and norepinephrine compared with control VSMCs. IP3R1VSMC–/– mice displayed significantly reduced responses to ATII, both in vivo and ex vivo. HF IP3R1VSMC–/– mice developed significantly less afterload compared with HF IP3R1fl/fl mice and exhibited significantly attenuated progression toward decompensated HF and reduced interstitial fibrosis. Ca2+-dependent phosphorylation of the MLC by MLCK activated VSMC contraction. MLC phosphorylation was markedly increased in VSMCs from patients with HF and HF mice but reduced in VSMCs from HF IP3R1VSMC–/– mice and HF WT mice treated with ML-7. Taken together, our data indicate that VSMC IP3R1 is a major effector of increased vascular tone, which contributes to increased cardiac afterload and decompensation in HF.  相似文献   
48.
49.
Therapeutics targeting osteoclasts are commonly used treatments for bone metastasis; however, whether and how osteoclasts regulate premetastatic niche and bone tropism are largely unknown. In this study, we report that osteoclast precursors (OPs) can function as a premetastatic niche component that facilitates breast cancer (BCa) bone metastasis at early stages. At the molecular level, unbiased GPCR ligand/agonist screening in BCa cells suggested that R-spondin 2 (RSPO2) and RANKL, through interaction with their receptor LGR4, promoted osteoclastic premetastatic niche formation and enhanced BCa bone metastasis. This was achieved by RSPO2/RANKL-LGR4 signal modulating the WNT inhibitor DKK1 through Gαq and β-catenin signaling. DKK1 directly facilitated OP recruitment through suppression of its receptor LDL receptor–related protein 5 (LRP5) but not LRP6, upregulating Rnasek expression via inhibition of canonical WNT signaling. In clinical samples, RSPO2, LGR4, and DKK1 expression showed a positive correlation with BCa bone metastasis. Furthermore, soluble LGR4 extracellular domain (ECD) protein, acting as a decoy receptor for RSPO2 and RANKL, significantly alleviated bone metastasis and osteolytic lesions in a mouse bone metastasis model. These findings provide unique insights into the functional role of OPs as key components of the premetastatic niche for BCa bone metastasis and identify RSPO2/RANKL-LGR4 signaling as a promising target for inhibiting BCa bone metastasis.  相似文献   
50.
目的 实现三级生物安全(BSL-3)实验室各区域的压强梯度、温度与湿度等各项指标的动态平衡,保证工程屏障的生物安全防护作用.方法 设计了BSL-3实验室空气指标自动化控制系统.该系统在变送器及专用数据采集设备的基础上采用直接数字控制模式(DDC)控制,并设置图形监控系统.上位机可同时对各项指标进行实时记录存盘并分析处理,根据实时情况对相应输出设备进行调节,对超过设定限值的数据发出报警.结果 该系统能实时采集BSL-3实验室各区域、空调机组、空气过滤器等所有监控点的压力、温度、湿度、阻力、设备运行状况等模拟量信号和风机、电动执行器等的启停(运行)状态以及报警信息,以彩色动态仿真图形显示,并实时对设施的运行进行控制.监控中心可通过DDC控制器远程修改现场的控制参数,系统自动调节相关设备的输出量.监控中心自动执行警报,强制画面显示报警的环节和原因,工作人员可根据用户等级来处理报警信息.结论 该自控系统可实时有效地对室内环境指标状态以及设施的运行状况等进行监控,满足了实验室的生物安全要求.  相似文献   
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