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61.
对造成巨大生命财产损失的滑坡灾害,分析了其发展过程中的力学参数变化,提出用数字式遥感土压力仪与变形仪对之进行实时连续遥测和预报预警,认为钨铼合金丝式振弦仪器适于此类观测,其测定值是可靠的.  相似文献   
62.
以西藏多龙斑岩型铜矿区为例,根据已知矿床,分别利用比值法和主成分分析法对ETM+和ASTER数据提取铁染与羟基异常信息,分析研究已知矿体遥感异常特征;通过波谱特征拟合的方法,对研究区进行波谱分类。利用两方面的成果来对多龙矿集区作成矿预测,划定远景成矿区,其中一级预测区6个,二级预测区12个。多种异常对比组合,能够发现更好的指示成矿线索的信息。  相似文献   
63.
智能控制-维护-管理系统(ICMMS)中预知维护的研究   总被引:2,自引:0,他引:2  
智能控制-维护-管理系统是自动化领域的发展方向,以状态监测和预测为基础的预知维护是实现智能控制-维护-管理系统的基础之一;预知维护是监测与预测、诊断与预诊断、维护策略制定三要素的集成;预知维护也是ICMMS平台研究的重点之一,在ICMMS平台对电液伺服机构的预知维护进行了重点研究,并利用神经网络技术进行了实现。  相似文献   
64.
Even though the new thresholds for defining prediabetes have been around for more than ten years, there is still controversy surrounding the precise characterization of this intermediate glucose metabolism status. The risk of developing diabetes and macro and microvascular disease linked to prediabetes is well known. Still, the prediabetic population is far from being homogenous, and phenotyping it into less heterogeneous groups might prove useful for long-term risk assessment, follow-up, and primary prevention. Unfortunately, the current definition of prediabetes is quite rigid and disregards the underlying pathophysiologic mechanisms and their potential metabolic progression towards overt disease. In addition, prediabetes is commonly associated with a cluster of risk factors that worsen the prognosis. These risk factors all revolve around a common denominator: inflammation. This review focuses on identifying the population that needs to be screened for prediabetes and the already declared prediabetic patients who are at a higher risk of cardiovascular disease and require closer monitoring.  相似文献   
65.
Globally, HIV/AIDS and cancer are increasingly public health problems and continue to exist as comorbidities. The sub-Saharan African region has the largest number of HIV infections. Malignancies previously associated with HIV/AIDS, also known as the AIDS-defining cancers (ADCs) have been documented to decrease, while the non-AIDS defining cancer (NADCs) are on the rise. On the other hand, cancer is a highly heterogeneous disease and precision oncology as the most effective cancer therapy is gaining attraction. Among HIV-infected individuals, the increased risk for developing cancer is due to the immune system of the patient being suppressed, frequent coinfection with oncogenic viruses and an increase in risky behavior such as poor lifestyle. The core of personalised medicine for cancer depends on the discovery and the development of biomarkers. Biomarkers are specific and highly sensitive markers that reveal information that aid in leading to the diagnosis, prognosis and therapy of the disease. This review focuses mainly on the risk assessment, diagnostic, prognostic and therapeutic role of various cancer biomarkers in HIV-positive patients. A careful selection of sensitive and specific HIV-associated cancer biomarkers is required to identify patients at most risk of tumour development, thus improving the diagnosis and prognosis of the disease.  相似文献   
66.
Accumulating evidence indicates that the reliable gene signature may serve as an independent prognosis factor for lung adenocarcinoma (LUAD) diagnosis. Here, we sought to identify a risk score signature for survival prediction of LUAD patients. In the Gene Expression Omnibus (GEO) database, GSE18842, GSE75037, GSE101929, and GSE19188 mRNA expression profiles were downloaded to screen differentially expressed genes (DEGs), which were used to establish a protein-protein interaction network and perform clustering module analysis. Univariate and multivariate proportional hazards regression analyses were applied to develop and validate the gene signature based on the TCGA dataset. The signature genes were then verified on GEPIA, Oncomine, and HPA platforms. Expression levels of corresponding genes were also measured by qRT-PCR and Western blotting in HBE, A549, and PC-9 cell lines. The prognostic signature based on eight genes (TTK, HMMR, ASPM, CDCA8, KIF2C, CCNA2, CCNB2, and MKI67) was established, which was independent of other clinical factors. The risk model offered better discrimination between risk groups, and patients with high-risk scores tended to have poor survival rate at 1-, 3- and 5-year follow-up. The model also presented better survival prediction in cancer-specific cohorts of age, gender, clinical stage III/IV, primary tumor 1/2, and lymph node metastasis 1/2. The signature genes, moreover, were highly expressed in A549 and PC-9 cells. In conclusion, the risk score signature could be used for prognostic estimation and as an independent risk factor for survival prediction in patients with LUAD.  相似文献   
67.
Chemokines secreted from stromal cells have important roles for interactions with carcinoma cells and regulating tumor progression. C-C motif chemokine ligand (CCL) 5 is expressed in various types of stromal cells and associated with tumor progression, interacting with C-C chemokine receptor (CCR) 1, 3 and 5 expressed in tumor cells. However, the expression on CCL5 and its receptors have so far not been well-examined in human breast carcinoma tissues. We therefore immunolocalized CCL5, as well as CCR1, 3 and 5, in 111 human breast carcinoma tissues and correlated them with clinicopathological characteristics. Stromal CCL5 immunoreactivity was significantly correlated with the aggressive phenotype of breast carcinomas. Importantly, this tendency was observed especially in the CCR3-positive group. Furthermore, the risk of recurrence was significantly higher in the patients with breast carcinomas positive for CCL5 and CCR3 but negative for CCR1 and CCR5, as compared with other patients. In summary, the CCL5-CCR3 axis might contribute to a worse prognosis in breast cancer patients, and these findings will contribute to a better understanding of the significance of the CCL5/CCRs axis in breast carcinoma microenvironment.  相似文献   
68.
In the chemical industry, real‐time flooding prognosis is a necessity for packed‐column operation because the flooding phenomenon interferes with the performance of production systems. In this work, the profile monitoring technique is utilized to capture the dynamic behavior of pressure drop, which is an important indicator for the flooding phenomenon. In each moving window, the pressure drop signals are described by using an exponential generalized autoregressive conditional heteroskedastic model. The onset of the flooding phenomenon is then indicated by changes in model parameters. Moreover, to efficiently capture the process change, a nonparametric approach is utilized to establish a statistical control chart. Experimental and comparison results show the advantages of the proposed method.  相似文献   
69.
南岭地区是我国重要的有色、稀有金属矿产资源产地,是世界上研究燕山期花岗岩成岩成矿理论最典型的地区之一。该地区多金属矿床与花岗岩侵入关系密切,因此,研究花岗岩的空间分布特征对于成矿规律以及成矿远景预测有重要意义。南岭花岗岩密度较围岩低,呈明显重力负异常特征,本文首先建立直立柱体花岗岩的重力正演模型,通过改变模型参数来分析南岭花岗岩局部重力异常的特征;然后对南岭地区实测布格重力异常采用滑动平均法分离出局部重力异常和区域重力场,并对其特征进行了分析;最后选择过骑田岭、香花岭等地区典型剖面,通过二度半人机交互反演方法得出花岗岩体的形态与侵位特征,得知大型花岗岩体下底延深不超过25km,其侵位机制大多受深大断裂控制,说明南岭花岗岩侵入体属浅源型。  相似文献   
70.
本文研究分布式模糊离散事件系统的故障预测问题.先根据系统的模糊特性,提出一种分布式模糊离散事件系统的协同可预测性的形式化方法,使分布式模糊离散事件系统的协同可预测度不小于各分站点的局部可预测度.通过构造协同预测验证器,提出一种基于协同预测验证器的协同预测算法,并得到一个关于分布式模糊离散事件系统协同可预测性的充分必要条件.  相似文献   
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