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21.
A Wireless Sensor Networks (WSNs) consists basically of a group of nodes, that communicate with each other through a wireless transmission, and does not need any existing infrastructure. The recent developments in technology and wireless communication, to be used in various applications, foster the development of Wireless Body Area Networks (WBANs). They are emerging as important networks in order to reduce the need for patients, and to help the elderly and chronically ill people to live an independent life. In this paper, we propose a routing protocol for wireless body area networks, to transfer data in the network with minimum energy consumption, and longer network lifetime through multi-hop communication. The proposed protocol has been verified by performing simulations, and the obtained results show that our routing protocol ensures a robust optimisation of the energy consumption which helps to increase the lifetime of the network and its stability.  相似文献   
22.
目的通过网络药理学的方法预测气滞胃痛颗粒抗炎镇痛主要活性成分的作用靶点,结合中医方解配伍理论对其多成分-多靶点-多通路的作用进行分析。方法基于TCMSP中药系统生物学分析数据库收集气滞胃痛颗粒中6味中药的主要化学成分,并借助LC-MS技术对所筛成分进行分析,通过TCMSP检索和Pharmmapper软件预测获取各成分主要的作用靶标,并通过DIP数据库,利用蛋白质相互作用信息建立药物靶标与炎症疼痛靶标的关联,构建药物-靶标-疾病网络,通过网络特征分析气滞胃痛颗粒抗炎镇痛的作用靶标,阐释其抗炎镇痛的主要作用机制。结果根据网络分析,共有44个炎症疼痛靶点与气滞胃痛颗粒密切相关,其中直接作用靶点有20个,主要是对环加氧酶-2(COX-2)和诱导型一氧化氮合酶(i NOS)等蛋白酶的作用,作用机制可能与调节肿瘤坏死因子(TNF)信号通路、NOD样受体(NLR)信号通路、血管内皮生长因子(VEGF)信号通路等与炎症疼痛密切相关的信号通路有关。结论气滞胃痛颗粒抗炎镇痛作用体现了中药多成分、多靶点、多途径的作用特点,该研究为深入阐释气滞胃痛颗粒抗炎镇痛作用机制提供科学依据,并且进一步说明了中医药古方配伍理论的科学性。  相似文献   
23.
中药复方是由2味或2味以上中药遵循中医理论组合而成的方剂。多味中药在合适的剂量配比之下,协同发挥作用,实现中医的整体调节治疗。研究中药复方的配伍对推动中药现代化发展、新药开发以及临床应用有着重要意义。近年来,研究者们在传统的"七情和合"与"君臣佐使"的基础上,运用新技术和新方法对中药复方的成分、药效活性和药代动力学性质等进行了研究,从不同角度探讨了中药复方配伍的科学内涵。同时,多种数理方法和模型的建立、网络药理学和数据挖掘方法的发展与应用,也对中药复方配伍研究提供了很大帮助。研究方法的发展虽促进了中药复方配伍的科学研究,但还需进一步建立适合中药复方配伍复杂关系的研究方法,以阐明中药复方及其成分/组分配伍的内在规律,进而构建新的现代中药复方,这也是目前中药复方配伍研究的重点任务。  相似文献   
24.
《Clinical neurophysiology》2019,130(5):727-738
ObjectiveFunctional processes in the brain are segregated in both the spatial and spectral domain. Motivated by findings reported at the cortical level in healthy participants we test the hypothesis in the basal ganglia of Parkinson’s disease patients that lower frequency beta band activity relates to motor circuits associated with the upper limb and higher beta frequencies with lower limb movements.MethodsWe recorded local field potentials (LFPs) from the subthalamic nucleus using segmented “directional” DBS leads, during which patients performed repetitive upper and lower limb movements. Movement-related spectral changes in the beta and gamma frequency-ranges and their spatial distributions were compared between limbs.ResultsWe found that the beta desynchronization during leg movements is characterised by a strikingly greater involvement of higher beta frequencies (24–31 Hz), regardless of whether this was contralateral or ipsilateral to the limb moved. The spatial distribution of limb-specific movement-related changes was evident at higher gamma frequencies.ConclusionLimb processing in the basal ganglia is differentially organised in the spectral and spatial domain and can be captured by directional DBS leads.SignificanceThese findings may help to refine the use of the subthalamic LFPs as a control signal for adaptive DBS and neuroprosthetic devices.  相似文献   
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26.
This study explores the forces that drive the formation of physician patient sharing networks. In particular, I examine the degree to which hospital affiliation drives physicians' sharing of Medicare patients. Using a revealed preference framework where observed network links are taken to be pairwise stable, I estimate the physicians' pair‐specific values using a tetrad maximum score estimator that is robust to the presence of unobserved physician specific characteristics. I also control for a number of potentially confounding patient sharing channels, such as (a) common physician group or hospital system affiliation, (b) physician homophily, (c) knowledge complementarity, (d) patient side considerations related to both geographic proximity and insurance network participation, and (e) spillover from other collaborations. Focusing on the Chicago hospital referral region, I find that shared hospital affiliation accounts for 36.5% of the average pair‐specific utility from a link. Implications for reducing care fragmentation are discussed.  相似文献   
27.
This study was performed to develop a low-cost smart system for identification and quantification of adulterated edible bird's nest (EBN). The smart system was constructed with a colorimetric sensor array (CSA), a smartphone and a multi-layered network model. The CSA were used to collect the odor character of EBN and the response signals of CSA were captured by the smartphone systems. The principal component analysis (PCA) and hierarchical cluster analysis (HAC) were used to inquiry the similarity among authentic and adulterated EBNs. The multi-layered network model was constructed to analyze EBN adulteration. In this model, discrimination of authentic EBN and adulterated EBN was realized using back-propagation neural networks (BPNN) algorithm. Then, another BPNN-based model was developed to identify the type of adulterant in the mixed EBN. Finally, adulterated percentage prediction model for each kind of adulterate EBN was built using partial least square (PLS) method. Results showed that recognition rates of the authentic EBN and adulterated EBN was as high as 90%. The correlation coefficient of percentage prediction model for calibration set was 0.886, and 0.869 for prediction set. The low-cost smart system provides a real-time, nondestructive tool to authenticate EBN for customers and retailers.  相似文献   
28.
29.
目的:通过网络药理学的方法筛选黄精-百合药对中的有效成分,预测治疗癌症的作用靶点及信号通路,进一步探讨潜在作用机制。方法:使用全称为中药系统药理学分析平台筛选黄精-百合药对中的活性成分和靶点,通过基因疾病关联数据库(Dis Ge NET)与人类孟德尔遗传数据库(OMIM)预测与筛选药对中有效的中药成分作用的疾病靶点。选择生物信息分析学习平台(Omicshare)匹配药物和疾病的靶点,借助复杂网络可视化平台(Cytoscape3. 7. 0)软件构建"药物-成分-疾病"网络。采用蛋白质相互作用网络数据库(String)构建黄精-百合药对治疗癌症的靶点相互作用的网络。最后通过功能注释生物信息学分析平台(DAVID)对黄精-百合药对中关键作用的节点进行生物功能及代谢通路分析。结果:筛选出19个黄精-百合药对的活性成分,根据靶点预测技术预测出相关靶点234个,与疾病靶点有关的活性成分为6个,主要通过调控丝氨酸(Akt)/苏氨酸激酶1(Akt1),Jun原癌基因,AP-1转录因子亚基(JUN),血管内皮生长因子A(VEGFA),基质金属蛋白酶-9(MMP-9),半胱氨酸蛋白酶-3(Caspase-3)等靶蛋白,以及癌症中的蛋白多糖,雌激素信号转导通路,人免疫缺陷病毒1感染,缺氧诱导因子-1(HIF-1)信号通路,肿瘤坏死因子(TNF)信号通路,癌症中的微型核糖核酸(MicroRNAs)等通路发挥抗癌作用。结论:黄精-百合药对治疗癌症的作用体现了中药多成分-多靶点-多途径的特点,为阐释其抗癌治疗的作用机制与物质基础提供了科学依据。  相似文献   
30.
BackgroundThe innovation of immune checkpoint blockade (ICB) represents a promising shift in the treatment of advanced hepatocellular carcinoma (HCC). However, response to ICB has varied largely due to the high tumor heterogeneity and complex tumor microenvironment (TME). The competitive endogenous RNA (ceRNA) network also plays an important role in tumor occurrence and progression, but its relation with tumor-infiltrating immune cells (TICs) remains largely unexplored in HCC. The overriding objective of our study was thus to construct a prognosis-related risk model and to further evaluate the relationship between ceRNA networks and TICs.MethodsDifferentially expressed gene (DEG) analysis was performed to identify the differentially expressed RNAs. Lasso and multivariable Cox regression analyses were used to construct risk models, which were assessed by the area under the receiver operating characteristic curve (AUC of ROC) and Kaplan-Meier (K-M) curves. Then, a single-sample gene set enrichment analysis (ssGSEA) algorithm was adopted to dissect the TICs in HCC samples. Nomograms were constructed and calibration curves were used to verify the discrimination and accuracy of the nomograms. Finally, integration analysis was performed to validate the correlation of ceRNA and TICs.ResultsIn the study, 7 differentially expressed RNAs [5 messenger RNA s (mRNAs) and 2 micro RNAs (miRNAs)] were incorporated to construct a ceRNA risk model. The AUC of the 1-, 3-, and 5-year overall survival (OS) were 0.784, 0.685, and 0.691 respectively. Likewise, 7 types TICs were in the TICs signature model and the AUC of the 1-, 3-, and 5-year OS were 0.706, 0.731, and 0.721 respectively. The integration analysis showed that 7 pairs of mRNA-TICs and 1 pair of miRNA-TICs had a close relation (all correlation coefficients >0.2, P<0.001).ConclusionsThrough constructing two risk models based on ceRNA network and TICs, we identified the hub RNAs and key TICs in the progression and prognosis of HCC, and further explored the relationship between ceRNA and TME. Importantly, targeting these hub RNAs may facilitate the remodeling of the TME and be a potential therapeutic alternative to enhancing the response to ICB, thus improving the prognosis of HCC patients.  相似文献   
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