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101.
DR Holmes HD White KS Pieper SG Ellis RM Califf EJ Topol 《Canadian Metallurgical Quarterly》1999,33(2):412-419
OBJECTIVES: The purpose of this study was to determine how risks associated with increasing age differed in patients treated with percutaneous transluminal coronary angioplasty versus thrombolysis. BACKGROUND: Advancing age is a risk factor for adverse outcome in patients with acute myocardial infarction. Primary angioplasty has been thought to be particularly beneficial in higher risk patients including the elderly. There is, however, limited data on any differential incremental benefit of angioplasty compared with thrombolysis in candidates for either treatment. METHODS: In the GUSTO-IIb angioplasty substudy, 1,138 patients were randomized to receive primary angioplasty or accelerated tissue-type plasminogen activator (t-PA). The effect of age on outcome was assessed as a discrete and continuous variable for each treatment group. Models using age as a linear factor as well as cubic spline transformations were used for the major end points of 30-day death or disabling stroke; death or reinfarction; and death, reinfarction or disabling stroke. RESULTS: For each 10-year patient group, outcome was improved with angioplasty (n = 565) compared with t-PA (n = 573). Irrespective of treatment, however, risk increased with age. After adjusting for baseline characteristics, each increment of 10 years of age increased the risk of death or myocardial infarction by 1.32 (95% confidence interval 1.04 to 1.76, p = 0.022). For all adverse outcomes, this incremental effect of increasing age was constant. CONCLUSIONS: Advancing age is associated with worse outcomes, and the risks increase in proportion to age. Although primary angioplasty improves outcomes over thrombolysis, it does not appear to be more beneficial in older than in younger patient groups. The incremental adverse effect of age does not vary by treatment strategy. 相似文献
102.
Carolin Czauderna Kim Luley Nikolas von Bubnoff Jens U. Marquardt 《International journal of molecular sciences》2021,22(21)
Liver metastases are the most common site of metastatic spread in colorectal cancer. Current treatment approaches involve effective systemic therapies in combination with surgical and/or interventional strategies. Multimodal strategies greatly improved clinical outcomes of patients with metastatic colorectal cancer over the last decades. Identification of predictive and prognostic biomarkers helped to comprehensively refine individual targeted treatment approaches and resulted in median overall survival rates of 30 months or longer. Current guidelines, thus, recommend treatment selection according to patients’ performance status, tumor localization and stage as well as the tumor’s molecular and genetic status. Here, we outline the latest developments in molecular decision-making for patients with upfront resectable, potentially or initially unresectable and non/never-resectable colorectal cancer liver metastases. 相似文献
103.
104.
The knowledge of the accurate laser tool position is of extreme importance for quality assurance during the laser beam welding. Already minimum deviations of the desired track can impair the result of the manufacturing process, e.g. due to tolerances of thermal deformation. A contribution of this problem is an optical sensor system, which detects the three-dimensional position of the weldseam in on-line coupling parallel to the welding process and then derives the actual laser beam position relative to the workpiece. Under laboratory conditions the function of the sensor system for the on-line tracking of the laser tool was tested successfully in connection with a handling system. 相似文献
105.
M Weidenbach C Wick S Pieper K J Quast T Fox G Grunst D A Redel 《Computers and biomedical research》2000,33(1):11-22
In two-dimensional echocardiography the sonographer must synthesize multiple tomographic slices into a mental three-dimensional (3D) model of the heart. Computer graphics and virtual reality environments are ideal to visualize complex 3D spatial relationships. In augmented reality (AR) applications, real and virtual image data are linked, to increase the information content. In the presented AR simulator a 3D surface model of the human heart is linked with echocardiographic volume data sets. The 3D echocardiographic data sets are registered with the heart model to establish spatial and temporal congruence. The heart model, together with an animated ultrasound sector represents a reference scenario, which displays the currently selected two-dimensional echocardiographic cutting plane calculated from the volume data set. Modifications of the cutting plane within the echocardiographic data are transferred and visualized simultaneously and in real time within the reference scenario. The trainee can interactively explore the 3D heart model and the registered 3D echocardiographic data sets by an animated ultrasound probe, whose position is controlled by an electromagnetic tracking system. The tracking system is attached to a dummy transducer and placed on a plastic puppet to give a realistic impression of a two-dimensional echocardiographic examination. 相似文献
106.
This work includes the creation and validation of a computer model of a liquid helium cryostat located at the Canadian Light Source (CLS) in Saskatoon, Canada. This cryostat contains a superconducting radio frequency (RF) cavity, and requires careful pressure and level modulation to ensure proper RF control. A detailed mathematical model of the cryostat is generated based on gas and liquid mass balances for a boiling vessel, along with pressure-volume-temperature relations. The model is discretized and solved, and model results are compared with experimental data taken from the actual cryostat at the CLS to determine the accuracy of the simulation. The model is found to reasonably represent the cryostat at the CLS from a process perspective. 相似文献
107.
Carolin Gabler Carmen Zietz Rebecca G?hler Andreas Fritsche Tobias Lindner Maximilian Haenle Birgit Finke Jürgen Meichsner Solvig Lenz Bernhard Frerich Frank Lüthen J. Barbara Nebe Rainer Bader 《International journal of molecular sciences》2014,15(2):2454-2464
By means of plasma polymerization, positively charged, nanometre-thin coatings can be applied to implant surfaces. The aim of the present study was to quantify the adhesion of human bone cells in vitro and to evaluate the bone ongrowth in vivo, on titanium surfaces modified by plasma polymer coatings. Different implant surface configurations were examined: titanium alloy (Ti6Al4V) coated with plasma-polymerized allylamine (PPAAm) and plasma-polymerized ethylenediamine (PPEDA) versus uncoated. Shear stress on human osteoblast-like MG-63 cells was investigated in vitro using a spinning disc device. Furthermore, bone-to-implant contact (BIC) was evaluated in vivo. Custom-made conical titanium implants were inserted at the medial tibia of female Sprague-Dawley rats. After a follow-up of six weeks, the BIC was determined by means of histomorphometry. The quantification of cell adhesion showed a significantly higher shear stress for MG-63 cells on PPAAm and PPEDA compared to uncoated Ti6Al4V. Uncoated titanium alloyed implants showed the lowest BIC (40.4%). Implants with PPAAm coating revealed a clear but not significant increase of the BIC (58.5%) and implants with PPEDA a significantly increased BIC (63.7%). In conclusion, plasma polymer coatings demonstrate enhanced cell adhesion and bone ongrowth compared to uncoated titanium surfaces. 相似文献
108.
Martin Meng Carolin Ahlborn Dr. Matthias Bauer Dr. Oliver Plietzsch Shahid A. Soomro Dr. Arunoday Singh Thierry Muller Dr. Wolfgang Wenzel Dr. Stefan Bräse Prof. Clemens Richert Prof. 《Chembiochem : a European journal of chemical biology》2009,10(8):1335-1339
Tetrahedral DNA hybrids with tetrakis(p‐hydroxyphenyl)methane cores hybridize in a sequence‐specific fashion at much higher temperatures than isolated linear duplexes. Dinucleotide DNA arms suffice to induce the formation of a solid at room temperature; this demonstrates the strength of multivalent binding. The graphic shows a view of a modeled assembly.
109.
In this paper we present both finite element based and analytic model simulations of pentacene based organic thin film transistor.
The finite element type simulation is done using Silvaco’s Atlas simulator and the analytic model simulation is performed
using a Matlab code based on the standard transistor equations. Both the Atlas and Matlab simulations agree approximately
with the published experimental result. The results of the simulations show a current ratio of 2.11×106 for Atlas and 1.8×107 for Matlab simulations. The threshold voltage extracted from the finite element type simulation is 1.1 V which is in good
agreement with 1.2 V used for Matlab simulation. However, the contact resistance shows a quite significant variation between
the two simulation mechanisms. The finite element type simulation gives a contact resistance of 10 kΩ whereas the Matlab simulation
predicts a contact resistance 1.9 kΩ. 相似文献
110.
Daniel Gruhl Meena Nagarajan Jan Pieper Christine Robson Amit Sheth 《The VLDB Journal The International Journal on Very Large Data Bases》2010,19(6):825-848
Social Networks provide one of the most rapidly evolving data sets in existence today. Traditional Business Intelligence applications
struggle to take advantage of such data sets in a timely manner. The BBC SoundIndex, developed by the authors and others,
enabled real-time analytics of music popularity using data from a variety of Social Networks. We present this system as a
grounding example of how to overcome the challenges of working with this data from social networks. We discuss a variety of
technologies to implement near real-time data analytics to transform Social Intelligence into Business Intelligence and evaluate
their effectiveness in the music domain. The SoundIndex project helped to highlight a number of key research areas, including
named entity recognition and sentiment analysis in Informal English. It also drew attention to the importance of metadata
aggregation in multimodal environments. We explored challenges such as drawing data from a wide set of sources spanning a
myriad of modalities, developing adjudication techniques to harmonize inputs, and performing deep analytics on extremely challenging
Informal English snippets. Ultimately, we seek to provide guidance on developing applications in a variety of domains that
allow an analyst to rapidly grasp the evolution in the social landscape, and show how to validate such a system for a real-world
application. 相似文献