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101.
Peripheral neurologic complications are frequent adverse events during oncologic treatments and often lead to dose reduction, administration delays with time elongation of the therapeutic plan and, not least, worsening of patients’ quality of life. Experience skills are required to recognize symptoms and clinical evidences and the collaboration between different health professionals, in particular oncologists and hospital pharmacists, grants a correct management of this undesirable occurrence. Some classes of drugs (platinates, vinca alkaloids, taxanes) typically develop this kind of side effect, but the genesis of chemotherapy-induced peripheral neuropathy is not linked to a single mechanism. This paper aims from one side at summarizing and explaining all the scattering mechanisms of chemotherapy-induced peripheral neuropathy through a detailed literature revision, on the other side at finding new approaches to possible treatments, in order to facilitate the collaboration between oncologists, hematologists and hospital pharmacists.  相似文献   
102.
The development of electronics capable of interfacing with the nervous system is a rapidly advancing field with applications in basic science and clinical translation. Devices containing arrays of electrodes can be used in the study of cells grown in culture or can be implanted into damaged or dysfunctional tissue to restore normal function. While devices are typically designed and used exclusively for one of these two purposes, there have been increasing efforts in developing implantable electrode arrays capable of housing cultured cells, referred to as biohybrid implants. Once implanted, the cells within these implants integrate into the tissue, serving as a mediator of the electrode–tissue interface. This biological component offers unique advantages to these implant designs, providing better tissue integration and potentially long-term stability. Herein, an overview of current research into biohybrid devices, as well as the historical background that led to their development are provided, based on the host anatomical location for which they are designed (CNS, PNS, or special senses). Finally, a summary of the key challenges of this technology and potential future research directions are presented.  相似文献   
103.
Concentrated Growth Factors (CGF) represent new autologous (blood-derived biomaterial), attracting growing interest in the field of regenerative medicine. In this study, the chemical, structural, and biological characterization of CGF was carried out. CGF molecular characterization was performed by GC/MS to quantify small metabolites and by ELISA to measure growth factors and matrix metalloproteinases (MMPs) release; structural CGF characterization was carried out by SEM analysis and immunohistochemistry; CGF has been cultured, and its primary cells were isolated for the identification of their surface markers by flow cytometry, Western blot, and real-time PCR; finally, the osteogenic differentiation of CGF primary cells was evaluated through matrix mineralization by alizarin red staining and through mRNA quantification of osteogenic differentiation markers by real-time PCR. We found that CGF has a complex inner structure capable of influencing the release of growth factors, metabolites, and cells. These cells, which could regulate the production and release of the CGF growth factors, show stem features and are able to differentiate into osteoblasts producing a mineralized matrix. These data, taken together, highlight interesting new perspectives for the use of CGF in regenerative medicine.  相似文献   
104.
We present the design, implementation, and testing of a novel picosecond optical parametric preamplifier system to generate high-energy seed pulses for the Vulcan laser facility. The preamplifier amplifies 100?fs pulses stretched to 3?ps pulses from 10?pJ to 70 μJ in a single stage of amplification before the pulses are further amplified in the Vulcan high-power Nd:glass laser facility to the petawatt power level. This increased seed energy has led to an improvement of the nanosecond amplified spontaneous emission contrast intensity to 10(-10) of the main pulse, without degrading the output of the laser system.  相似文献   
105.
Food safety represents one of the main issues of national and international agencies appointed to health control. In April 2003, a French agency disclosed that powdered or smashed hot chili pepper imported from India and Pakistan was heavily contaminated with a carcinogenic azo dye known as Sudan I. This paper deals with a modern approach for assaying the content of this colorant in foodstuff down to a limit of a few tens of parts per billion. The isotope dilution method combined with APCI tandem mass spectrometry was used. The internal standard, 1-(d5-phenylazo)-2-naphthalenol, was obtained by simple chemistry, and its structure was determined by 1H NMR spectroscopy. The mass spectrometric method is more sensitive than the HPLC approach by a factor of 20.  相似文献   
106.
We present the design guidelines and the experimental characterization of a multichannel acquisition system that measures the amplitude and the time-of-arrival of the signal pulses delivered by position-sensing silicon drift detectors (SDDs). The readout system has been equally developed for multichannel SDDs and for controlled drift detectors (CDDs) intended for spectroscopic imaging of X-rays or charged particles. The analog section includes a very large scale integration (VLSI) front-end preamplifier and bias current generator for the on-chip JFET follower while the digital back-end is realized with 12 bit 100 MS/s 8-channel analog-to-digital converter (ADC) versa modular eurocard (VME) boards. Amplitude and time are measured by digitally processing each unipolar shaped pulse also in presence of a superposed background waveform. The VME modularity allows the expansion of the readout system up to 128 channels per VME crate. The overall linearity error is better than 0.05%, and the mean noise over all channels, expressed in terms of equivalent noise charge, is about 4 electrons r.m.s. The measured time resolution is 0.6 ns r.m.s. at a signal charge of 5000 electrons, corresponding to a position resolution of 2-3 /spl mu/m r.m.s. along the drift direction. The developed readout system has been used for X-ray imaging tests with CDDs at Sincrotrone Trieste.  相似文献   
107.
A low-power phase-shift keying demodulator integrated circuit (IC) has been implemented using silicon-on-insulator CMOS technology for deep space and satellite applications. The demodulator employs double differential detection to increase its robustness to the Doppler shift caused by the movement of the space vehicle and sampling technique with 1-bit analog-to-digital converter (ADC) at the front to reduce the complexity and power dissipation. In particular, digital decimation is used after sampling to achieve a low power implementation of multirate transmission. Operating at ultra-high-frequency (435 MHz), the receiver system supports a wide range of data rates (0.1-100 Kbps). From test results, the power consumption of the demodulator circuit including the 1-bit ADC is below 1 mW for data rates up to 100 Kbps  相似文献   
108.
109.
This article examines the effective flexural modulus of a multilayered micro-system evolving into alternative layered structures consisting of three dissimilar materials. A multiscale model of the bending stiffness is presented to capture the impact of changing the constituent materials, the layer architecture and the cross-section geometry. The results are plotted onto maps to show the existence of specific domains, within which fall the effective properties of all possible tri-material multilayered configurations. The potential to stiffen a bi-material system is demonstrated by integrating additional layers of a more flexible material for given constraints on the volume fraction. The proposed scheme is conducive to contrast structural alternatives in constrained and unconstrained design. A case study shows how the maps enable optimum selection among various design concepts, which may range from monolithic materials with alternative shape geometries to systems consisting of two and three materials arranged in dissimilar multiple layer architectures.  相似文献   
110.
In this paper, a model reference control strategy is proposed in order to perform trajectory tracking in Takagi–Sugeno–Lipschitz (TSL) systems. Since the state vector is assumed not to be completely available for measurement, a proportional observer is added to the control scheme in order to apply an estimate‐feedback control action instead of a state‐feedback one. The overall design of both the controller and the observer gains are performed using a Lyapunov‐based quadratic boundedness specification, in order to improve the robustness against unknown exogenous disturbances. It is shown that the conditions that ensure convergence within ellipsoidal regions of the tracking and estimation errors can be expressed in the form of a linear matrix inequality (LMI) formulation. The effectiveness of the developed control strategy is demonstrated by means of simulation results.  相似文献   
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