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71.
目的探讨心血管内科医护人员的焦虑状况。方法采用焦虑自评量表(self-rating anxiety scale,SAS)对98名心血管内科医护人员进行问卷调查,并与国内常模比较。了解心血管内科医护人员焦虑状况。结果非焦虑者35名,占35.7%,焦虑者63名,占64.3%;心血管内科医护人员焦虑水平明显高于国内常模(P<0.05);心血管内科护士焦虑水平明显高于医生(P<0.05)。结论心血管医务人员心理健康状况与医疗职业特点密切相关,医护人员焦虑水平明显高于国内常模,护士焦虑水平明显高于医生,应切实提高其心理应对能力。  相似文献   
72.
Melatonin confers cardioprotective effect against myocardial ischemia/reperfusion (MI/R) injury by reducing oxidative stress. Activation of silent information regulator 1 (SIRT1) signaling also reduces MI/R injury. We hypothesize that melatonin may protect against MI/R injury by activating SIRT1 signaling. This study investigated the protective effect of melatonin treatment on MI/R heart and elucidated its potential mechanisms. Rats were exposed to melatonin treatment in the presence or the absence of the melatonin receptor antagonist luzindole or SIRT1 inhibitor EX527 and then subjected to MI/R operation. Melatonin conferred a cardioprotective effect by improving postischemic cardiac function, decreasing infarct size, reducing apoptotic index, diminishing serum creatine kinase and lactate dehydrogenase release, upregulating SIRT1, Bcl‐2 expression and downregulating Bax, caspase‐3 and cleaved caspase‐3 expression. Melatonin treatment also resulted in reduced myocardium superoxide generation, gp91phox expression, malondialdehyde level, and increased myocardium superoxide dismutase (SOD) level, which indicate that the MI/R‐induced oxidative stress was significantly attenuated. However, these protective effects were blocked by EX527 or luzindole, indicating that SIRT1 signaling and melatonin receptor may be specifically involved in these effects. In summary, our results demonstrate that melatonin treatment attenuates MI/R injury by reducing oxidative stress damage via activation of SIRT1 signaling in a receptor‐dependent manner.  相似文献   
73.
目的 探讨参白解毒方(SBJDF)抑制结直肠癌(CRC)细胞HCT116增殖的药效及机制。方法 利用参白解毒方(0、0.25、0.5、1、2、4 g·L-1)处理HCT116细胞48 h,噻唑蓝(MTT)比色法检测参白解毒方对HCT116细胞活力的影响,分别设置空白组、参白解毒方(1、2、4 g·L-1)组,倒置显微镜观察参白解毒方对HCT116细胞形态的影响,克隆形成实验观察参白解毒方对HCT116细胞增殖能力的影响,JC-1探针检测参白解毒方对HCT116细胞线粒体膜电位(Δψm)的影响,流式细胞仪检测HCT116细胞周期分布和细胞凋亡率,蛋白免疫印迹法(Western blot)分析参白解毒方对细胞周期,抗凋亡以及核转录因子-κB(NF-κB)信号通路相关蛋白的影响。结果 参白解毒方有效抑制HCT116细胞活力,引起细胞形态改变,呈浓度依赖性;与空白组比较,参白解毒方(1、2、4 g·L-1)组克隆形成率均明显下降(P<0.05,P<0.01),参白解毒方(2、4 g·L-1)组诱导HCT116细胞发生G0/G1期阻滞(P<0.05,P<0.01)。与空白组比较,参白解毒方(1、2、4 g·L-1)组周期蛋白D1(CyclinD1)表达明显下降(P<0.05,P<0.01),参白解毒方(2、4 g·L-1)组细胞周期蛋白A2(CyclinA2),周期蛋白依赖性激酶4(CDK4)蛋白表达明显下降(P<0.05,P<0.01),参白解毒方(4 g·L-1)组周期蛋白依赖性激酶1(CDK1)表达显著下降(P<0.01)。与空白组比较,参白解毒方(2、4 g·L-1)组课诱导HCT116细胞凋亡,并下调抗凋亡相关蛋白B淋巴细胞瘤-2(Bcl-2)、Bcl-2相关xl蛋白(Bcl-xl)表达(P<0.05,P<0.01),降低HCT116细胞线粒体膜电位;与空白组比较,参白解毒方(2、4 g·L-1)组可下调NF-κB信号通路相关蛋白IκB激酶α(IKKα)、NF-κB抑制蛋白α(IκBα)、磷酸化p65蛋白(p-p65)的表达(P<0.05,P<0.01)。结论 参白解毒方有效抑制HCT116细胞增殖,其机制可能通过抑制HCT116细胞NF-κB信号通路的激活,引起细胞周期阻滞,诱导细胞凋亡。  相似文献   
74.
The purpose of this study was to provide a simulation therapy environment for microwave thermal ablation (MWA) under the guidance of ultrasound, and to present an inexpensive and portable simulator built on real patient-based pre-operative computed tomography (CT) data. We established an experimental simulation system for teaching MWA and present the results of a preliminary evaluation of the simulator’s realism and utility for training. The system comprises physical elements of an electromagnetic tracking device and an abdominal phantom, and software elements providing three-dimensional (3D) image processing tools, real-time navigation functions and objective evaluation function module. Details of the novel aspects of this system are presented, including a portable electromagnetic tracking device, adoption of real patient-based pre-operative CT data of liver, operation simulation of MWA, and recording and playback of the operation simulation. Patients with liver cancer were selected for evaluation of the clinical application value of the experimental simulation system. A total of 50 consultant interventional radiologists and 20 specialist registrars in radiology rated the simulator’s hardware reality and overall ergonomics. Results show that the simulator system we describe can be used as a training tool for MWA. It enables training with real patient cases prior to surgery, and it can provide a realistic simulation of the actual procedure.  相似文献   
75.
Zhai S  Zhuang Y  Song Y  Li S  Huang D  Kang W  Li X  Liao Q  Liu Y  Zhao Z  Lu Y  Sun Y 《Current HIV research》2008,6(4):335-350
To assess the immunodominance patterns of HIV-1-specific cytotoxic T lymphocyte (CTL) responses and the contribution of these responses against the peptides scanning optimal epitopes in chronic infection, we test the HIV-1-specific CTL responses against a panel of 413 overlapping peptides spanning HIV-1 Asian B sequence, including 147 peptides corresponding to optimal clade B epitopes in 49 chronically HIV-1 infected individuals by interferon-gamma Elispot assay. A large variation in the recognition of peptides restricted by the same HLA class I allele is presented. Some epitopes are targeted frequently by individuals while other epitopes restricted by the same allele are rarely recognized in our research. HLA-B35 and HLA-A03 rather than other HLA alleles contribute greatly to total virus-specific CTL responses. Furthermore, there is a significant inverse correlation between the total contribution of HIV-1-specific CTL responses restricted by different HLA alleles to virus-specific immune responses and viral load in the individuals during advanced infection (P=0.002, r=-0.549). The peptides targeted by individuals have significantly lower entropy compared with those not targeted but restricted by the same HLA class I alleles (P<0.05) in 49 individuals infected by HIV-1, especially the advanced infection subgroup (P=0.044). These data demonstrate that the consistent immunodominance patterns of HIV-1-specific CTL responses of Chinese HIV-1 infected individuals and an inverse correlation between the relative contribution of responses restricted by HLA alleles and viral load, which indicates the important protective effect of optimal epitopes against slow disease progression even in advanced infection.  相似文献   
76.
摘 要 目的:系统评价万古霉素首剂给予负荷剂量对患者临床结局的影响。方法:系统检索英文数据库PubMed,Embase,Cochrane Library,中文数据库CNKI,WanFang,CBM,纳入所有关于万古霉素首剂给予负荷剂量的研究。结局指标为感染治疗的有效率、目标浓度的达标率和肾毒性的发生率。结果:纳入1篇随机对照试验,2篇队列研究,共199名患者,其中1篇研究报道负荷剂量可以提高感染治疗的有效率[RR=1.27,95%CI(0.97,1.67),P>0.05],2篇研究报道负荷剂量可以提高目标浓度的达标率[RR=1.54,95%CI (0.72,3.30),P>0.05],1篇研究报道负荷剂量组与对照组的肾毒性发生率[RR=3.87,95%CI(0.46,32.57),P>0.05]。结论:万古霉素首剂给予负荷剂量可以提高感染治疗的有效率和目标浓度的达标率,但未显示出临床优势。  相似文献   
77.
目的 探讨基孔肯雅热临床特点及治疗与转归.方法 选取2010年9月至2010年11月东莞市诊治的133例基孔肯雅热患者为研究对象,所有患者行3年随访,分析其临床特征及治疗与预后.结果 基孔肯雅热病常见临床症状为发热、皮疹及关节疼痛,发生率分别为100.00%、91.72%和90.98%;关节疼痛中膝关节、脚踝及肘部关节受累较多,发生率分别为69.92%、64.66%和48.87%;关节疼痛女性明显多于男性,15岁以上患者易发生关节疼痛;关节疼痛症状在1年内基本消失,部分患者在2年甚至3年内消失,个别患者在3年后仍未消失.结论 基孔肯雅热病主要以发热、皮疹及关节痛为主要临床表现,关节疼痛受年龄等因素影响,治疗后1年患者内关节疼痛基本可消失,对症、支持治疗对基孔肯雅热有显著治疗效果.  相似文献   
78.
79.
To investigate the relationship between the changes in circulating CD45RO+T lymphocyte subsets following neoadjuvant therapy for rectal cancer in patients with locally advanced rectal cancer.The clinicopathological data of 185 patients with rectal cancer who received neoadjuvant therapy in the General Surgery Department of Beijing Chaoyang Hospital affiliated to Capital Medical University from June 2015 to June 2017 were analyzed. Venous blood samples were collected 1 week before neoadjuvant therapy and 1 week before surgery, and the expression of CD45RO+T was detected by flow cytometry. The receiver operating characteristic curve analysis was used to determine the optimal cut-off point of CD45RO+ratio. Log-rank test and multivariate Cox regression were used to analyze the overall survival rate (OS) and disease-free survival rate (DFS) associated with CD45RO+ratio.Circulating CD45RO+ratio of 1.07 was determined as the optimal cut-off point and CD45RO+ratio-high was associated with lower tumor regression grade grading (P = .031), T stage (P = .001), and tumor node metastasis (TNM) stage (P = .012). The 3-year DFS and OS rate in the CD45RO+ratio-high group was significantly higher than that in the CD45RO+ratio-low group (89.2% vs 60.1%, P<.001; 94.4% vs 73.2%, P<.001). The multivariate Cox analysis revealed that elevated CD45RO+ratio was an independent factor for better DFS (OR, 0.339; 95% CI, 0.153–0.752; P = .008) and OS (OR, 0.244; 95% CI,0.082–0.726; P = .011).Circulating CD45RO+ratio could predict the tumor regression grade of neoadjuvant therapy for rectal cancer, as well as long-term prognosis. These findings could be used to stratify patients and develop alternative strategies for adjuvant therapy.  相似文献   
80.

Aim:

SMXZF (a combination of ginsenoside Rb1, ginsenoside Rg1, schizandrin and DT-13) derived from Chinese traditional medicine formula ShengMai preparations) is capable of alleviating cerebral ischemia-reperfusion injury in mice. In this study we used network pharmacology approach to explore the mechanisms of SMXZF in the treatment of cardio-cerebral ischemic diseases.

Methods:

Based upon the chemical predictors, such as chemical structure, pharmacological information and systems biology functional data analysis, a target-pathway interaction network was constructed to identify potential pathways and targets of SMXZF in the treatment of cardio-cerebral ischemia. Furthermore, the most related pathways were verified in TNF-α-treated human vascular endothelial EA.hy926 cells and H2O2-treated rat PC12 cells.

Results:

Three signaling pathways including the NF-κB pathway, oxidative stress pathway and cytokine network pathway were demonstrated to be the main signaling pathways. The results from the gene ontology analysis were in accordance with these signaling pathways. The target proteins were found to be associated with other diseases such as vision, renal and metabolic diseases, although they exerted therapeutic actions on cardio-cerebral ischemic diseases. Furthermore, SMXZF not only dose-dependently inhibited the phosphorylation of NF-κB, p50, p65 and IKKα/β in TNF-α-treated EA.hy926 cells, but also regulated the Nrf2/HO-1 pathway in H2O2-treated PC12 cells.

Conclusion:

NF-κB signaling pathway, oxidative stress pathway and cytokine network pathway are mainly responsible for the therapeutic actions of SMXZF against cardio-cerebral ischemic diseases.  相似文献   
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