首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   144篇
  免费   22篇
电工技术   4篇
化学工业   35篇
金属工艺   12篇
机械仪表   2篇
建筑科学   4篇
能源动力   13篇
轻工业   47篇
无线电   6篇
一般工业技术   22篇
冶金工业   8篇
自动化技术   13篇
  2024年   1篇
  2023年   1篇
  2022年   1篇
  2021年   10篇
  2020年   5篇
  2019年   7篇
  2018年   17篇
  2017年   5篇
  2016年   13篇
  2015年   5篇
  2014年   4篇
  2013年   16篇
  2012年   15篇
  2011年   20篇
  2010年   7篇
  2009年   10篇
  2008年   5篇
  2007年   8篇
  2006年   3篇
  2005年   1篇
  2004年   1篇
  2003年   1篇
  2002年   1篇
  2001年   2篇
  2000年   1篇
  1997年   2篇
  1994年   1篇
  1993年   2篇
  1989年   1篇
排序方式: 共有166条查询结果,搜索用时 15 毫秒
1.
Diabetic neuropathy (DN), the most common chronic and progressive complication of diabetes mellitus (DM), strongly affects patients’ quality of life. DN could be present as peripheral, autonomous or, clinically also relevant, uremic neuropathy. The etiopathogenesis of DN is multifactorial, and genetic components play a role both in its occurrence and clinical course. A number of gene polymorphisms in candidate genes have been assessed as susceptibility factors for DN, and most of them are linked to mechanisms such as reactive oxygen species production, neurovascular impairments and modified protein glycosylation, as well as immunomodulation and inflammation. Different epigenomic mechanisms such as DNA methylation, histone modifications and non-coding RNA action have been studied in DN, which also underline the importance of “metabolic memory” in DN appearance and progression. In this review, we summarize most of the relevant data in the field of genetics and epigenomics of DN, hoping they will become significant for diagnosis, therapy and prevention of DN.  相似文献   
2.
In recent decades, dysregulation of proteases and atypical proteolysis have become increasingly recognized as important hallmarks of cancer, driving community-wide efforts to explore the proteolytic landscape of oncologic disease. With more than 100 proteases currently associated with different aspects of cancer development and progression, there is a clear impetus to harness their potential in the context of oncology. Advances in the protease field have yielded technologies enabling sensitive protease detection in various settings, paving the way towards diagnostic profiling of disease-related protease activity patterns. Methods including activity-based probes and substrates, antibodies, and various nanosystems that generate reporter signals, i.e., for PET or MRI, after interaction with the target protease have shown potential for clinical translation. Nevertheless, these technologies are costly, not easily multiplexed, and require advanced imaging technologies. While the current clinical applications of protease-responsive technologies in oncologic settings are still limited, emerging technologies and protease sensors are poised to enable comprehensive exploration of the tumor proteolytic landscape as a diagnostic and therapeutic frontier. This review aims to give an overview of the most relevant classes of proteases as indicators for tumor diagnosis, current approaches to detect and monitor their activity in vivo, and associated therapeutic applications.  相似文献   
3.
4.
Monoclinic scheelite-type BiVO4 is currently considered as one of the most promising non-titania photocatalysts, wheras tetragonal zircon-type BiVO4 is still poorly understood. Herein, a new and simple synthetic approach was applied and nanostructured single-phase zircon-type BiVO4 was successfully prepared by a controllable ethylene-glycol colloidal route. In addition, nanostructured monoclinic scheelite-type BiVO4 powders were also fabricated through annealing of the as-prepared samples. A comparative study of the two BiVO4 polymorphs was conducted and it turned out that the novel synthetic approach had a significant impact on porosity and photocatalytic performance of zircon-structured BiVO4. All the prepared materials, as-prepared and annealed, were mesoporous, while measured values of specific surface area of some zircon-structured samples (~34?m2/g) were ~7 times higher than those reported thus far for this phase. Interestingly, for the first time, zircon-type BiVO4, previously considered to be a poor photocatalyst, exhibited a better overall performance in degradation of methyl orange compared to monoclinic scheelite-type BiVO4. Hence, it could be expected that the here-presented synthesis and observations will both arouse interest in scarcely studied tetragonal zircon-type BiVO4 and facilitate as well as speed up further research of its properties.  相似文献   
5.
The region of the investigated receptor is situated in the southern part of the Adriatic Sea in the Mediterranean. The measuring station is located on the seashore, which, being considered as a border area, is representative for the qualitative and quantitative estimation of the influence of marine and continental aerosols on the content of major ions in precipitation. In the sampling period, precipitation in the region of the investigated receptor was more abundant during the summer and autumn than during the winter and spring. The most frequent precipitation heights were up to 20 mm, while high precipitation came exclusively from the continental region. The results of the measurements of ions readily soluble in water were used for the differentiation of marine from continental contributions of primary and secondary aerosols to their content in the precipitation. Using PCA, it was shown that main contribution of Cl(-), Na(+) and Mg(2+) came from primary marine aerosols, while the contribution from continental sources was dominant for the content of SO(4)(2-), NO(3)(-), NH(4)(+) and Ca(2+) in the precipitation. The continental origin of Ca(2+) was from a primary source, while SO(4)(2-), NO(3)(-) and NH(4)(+) were representatives of secondary aerosols produced by reactions between acid oxides and alkaline species in the atmosphere, but SO(4)(2-) and NO(3)(-) also exist in the precipitation as free acids. The origin of the trace elements Cd, Cu, Pb and Zn in the precipitation came from anthropogenic emission sources. The results obtained in this work are based on experimental data from 609 samples collected during the period 1995-2000.  相似文献   
6.
Parkinson’s disease is a neurodegenerative disorder that affects people worldwide. Careful management of patient’s condition is crucial to ensure the patient’s independence and quality of life. This is achieved by personalized treatment based on individual patient’s symptoms and medical history. The aim of this study is to determine patient groups with similar disease progression patterns coupled with patterns of medications change that lead to the improvement or decline of patients’ quality of life symptoms. To this end, this paper proposes a new methodology for clustering of short time series of patients’ symptoms and prescribed medications data, and time sequence data analysis using skip-grams to monitor disease progression. The results demonstrate that motor and autonomic symptoms are the most informative for evaluating the quality of life of Parkinson’s disease patients. We show that Parkinson’s disease patients can be divided into clusters ordered in accordance with the severity of their symptoms. By following the evolution of symptoms for each patient separately, we were able to determine patterns of medications change which can lead to the improvement or worsening of the patients’ quality of life.  相似文献   
7.
8.
Ternary Al-Ag-Ga system at 200 °C was experimentally and thermodynamically assessed. Isothermal section was extrapolated using optimized thermodynamic parameters for constitutive binary systems. Microstructure and phase composition of the selected alloy samples were analyzed using light microscopy, scanning electron microscopy combined with energy-dispersive spectrometry and x-ray powder diffraction technique. The obtained experimental results were found to be in a close agreement with the predicted phase equilibria. Hardness and electrical conductivity of the alloy samples from four vertical sections Al-Ag80Ga20, Al-Ag60Ga40, Ag-Al80Ga20 and Ag-Al60Ga40 of the ternary Al-Ag-Ga system at 200 °C were experimentally determined using Brinell method and eddy current measurements. Additionally, hardness of the individual phases present in the microstructure of the studied alloy samples was determined using Vickers microhardness test. Based on experimentally obtained results, isolines of Brinell hardness and electrical conductivity were calculated for the alloys from isothermal section of the ternary Al-Ag-Ga system at 200 °C.  相似文献   
9.
In this study, different Ni–W coatings, obtained by cheap and technologically simple electrodeposition method, were examined as potential electrocatalysts for the hydrogen evolution reaction (HER). All electrodepositions were done on a Ni mesh substrate from ammoniacal-citrate bath containing different concentrations of Na2WO4. The influence of deposition parameters, such as deposition current density, pH and composition of ammoniacal-citrate bath on electrocatalytic activity of obtained Ni–W coatings toward HER was examined by polarization curve measurements in 6 M KOH at room temperature. The morphology and tungsten content of the Ni–W coatings were investigated by means of SEM and EDS analysis. All investigated electrodes have shown high electrocatalytic activity for the HER. The samples obtained at higher deposition current densities had the lowest overvoltage for the HER. It has been shown that the plating bath pH value is very important parameter in obtaining active coatings. Results of the analysis of polarization curves, morphology of deposited Ni–W coatings and the content of tungsten in the coatings, indicate that the surface roughness of the coatings is responsible for their catalytic activity towards HER.  相似文献   
10.
From the aspect of the development of a country, the energy sector represents a domain of strategic interest. Generation and use of energy resources most often belongs to the public sector, and are most often under the influence of the government in most countries. This paper analyzes the risks that are characteristic to the business of the public enterprise, Electric Power Industry of Serbia (EPS). EPS has started its restructuring and is adjusting to changes and challenges imposed by the launched reforms in the energy sector. However, due to certain limitations, it is still not possible to implement its complete restructuring and modernization. The paper aims to point at the risks a potential strategic partner faces. The risks have been identified as commercial, financial and political, classification immanent for project finance, and their evaluation was done using Failure Mode and Effects Analysis (FMEA). Risk analysis was performed based on current conditions for two potential scenarios that predict different types of changes in the analyzed period. The results of the analysis show that the potential strategic partner should pay special attention to price risks, estimation, investments, project activity neglect, quasi-risks and debt collection.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号