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1.
Currently, the extracellular matrix (ECM) is considered a pivotal complex meshwork of macromolecules playing a plethora of biomolecular functions in health and disease beyond its commonly known mechanical role. Only by unraveling its composition can we leverage related tissue engineering and pharmacological efforts. Nevertheless, its unbiased proteomic identification still encounters some limitations mainly due to partial ECM enrichment by precipitation, sequential fractionation using unfriendly-mass spectrometry (MS) detergents, and resuspension with harsh reagents that need to be entirely removed prior to analysis. These methods can be technically challenging and labor-intensive, which affects the reproducibility of ECM identification and induces protein loss. Here, we present a simple new method applicable to tissue fragments of 10 mg and more. The technique has been validated on human ovarian tissue and involves a standardized procedure for sample processing with an MS-compatible detergent and combined centrifugation. This two-step protocol eliminates the need for laborious sample clarification and divides our samples into 2 fractions, soluble and insoluble, successively enriched with matrisome-associated (ECM-interacting) and core matrisome (structural ECM) proteins.  相似文献   
2.
Persistent polyclonal B cell lymphocytosis (PPBL) is a rare lymphoproliferative disorder of unclear natural history and its potential for B cell malignancy remains unknown. We describe the case of a 39-year-old female who presented with stage IV-B large cell lymphoma 19 years after an initial diagnosis of PPBL; her disease was rapidly fatal despite intensive chemotherapy and blood stem cell transplantation. Because we had recently identified multiple bcl-2/Ig gene rearrangements in blood mononuclear cells of patients with PPBL, we sought evidence of this oncogene in this particular patient: bcl-2/Ig gene rearrangements were found in blood mononuclear cells but not in lymphoma cells. Owing to the possible role of Epstein-Barr virus (EBV) in the pathogenesis of PPBL, we also hypothesized our patient might have an EBV-related lymphoproliferative disorder. Despite serologies consistent with past exposure to this virus, it was not found in lymphoma cells using a sensitive polymerase chain reaction technique. We conclude that non-Hodgkin's lymphoma may occur during the course of PPBL. However, longer follow-up in more patients will be needed in order to better clarity the risk of hematologic malignancy in patients with PPBL.  相似文献   
3.
The finite element method is coupled with the topology gradient (TG) and level‐set (LS) methods for optimizing the shape of microwave components using a computer‐aided design model. On the one hand, the LS approach is based on the classical shape derivative; while on the other hand, the TG method is precisely designed for introducing new perturbations in the optimization domain. These two approaches, which consist in minimizing a cost function related to the component behavior, are first described. Regarding given electrical specifications, these techniques are applied to optimize the distribution of ceramic parts of a dual‐mode resonator in order to improve its behavior. The optimized dielectric resonators result in a wide spurious‐free stop band. A comparison between classical and optimized dual mode resonator is presented. Theoretical results are then validated by careful measurements. © 2009 Wiley Periodicals, Inc. Int J RF and Microwave CAE 2010.  相似文献   
4.
A new diffractive device for light coupling between a planar optical waveguide and free space is proposed. The device utilizes a second-order waveguide grating to diffract the fundamental waveguide mode into two free propagating beams and a subwavelength grating (SWG) mirror to combine the two free propagating beams into a single beam. The finite-difference time-domain (FDTD) simulations show that the SWG mirror improves the coupling efficiency of the waveguide fundamental mode into the single out-coupled beam from about 30% to 92%. A high efficiency (>90%) is predicted for a broad wavelength range of 1520-1580nm. The proposed device is compact (/spl sim/80 /spl mu/m in length) and it eliminates the need for blazing the waveguide grating.  相似文献   
5.
Microwave frequency capabilities of AlGaN/GaN high electron mobility transistors (HEMTs) on high resistive silicon (111) substrate for power applications are demonstrated in this letter. A maximum dc current density of 1 A/mm and an extrinsic current gain cutoff frequency (F/sub T/) of 50 GHz are achieved for a 0.25 /spl mu/m gate length device. Pulsed and large signal measurements show the good quality of the epilayer and the device processing. The trapping phenomena are minimized and consequently an output power density of 5.1 W/mm is reached at 18 GHz on a 2/spl times/50/spl times/0.25 /spl mu/m/sup 2/ HEMT with a power gain of 9.1dB.  相似文献   
6.
The authors demonstrate a SQW-GRINSCH ridge-waveguide electroabsorption modulator in GaAs/Al/sub x/Ga/sub 1-x/As that has a very high contrast ratio and low operating voltage and also acts as a laser with relatively low threshold current. They achieve contrast ratios of 10 dB/100 mu m of cavity length with an operating voltage of less than -4 V. In addition, when operated as laser, the device exhibits a threshold current of 25 mA. The active layer has a capacitance of 205 pF/mm/sup 2/ which would allow the fabrication of a device with a modulation bandwidth of over 20 GHz. The laser operated at a wavelength only 2-3 nm shorter than the optimum modulation wavelength.<>  相似文献   
7.
This paper reports the present status of GaAs based-heterojunction bipolar transistor (HBT) under development at Thales. We have developed a complete GaInP/GaAs-based technological process from material studies to discrete devices and microwave monolithic integrated circuits (MMIC) realisations. This know-how has been transferred recently to Thales/United monolithic semi-conductors. Discrete devices with output power over 1 W and power added efficiency (PAE) over 50% have been obtained at 10 GHz in CW. 8 W MMIC amplifiers have been fabricated using the same unit cells. The first reliability results are promising: more than 6000 h without failure for devices stressed up to 210°C and 40 kA cm−2. However, it seems that these results can still be improved. Some physical properties of the GaInP/GaAs HBT structures are suspected to have a major impact on the device reliability. The role of key parameters such as hydrogen incorporation in the GaAs base layer or residual strain in the GaInP/GaAs HBT structure has been investigated and its effects on the device characteristics identified. However, the major reliability improvement came from a novel way to passivate the extrinsic base surface. A comparison of the obtained results (device performance and reliability) with some of the best reported values in the literature (HP, TI, Daimler-Benz, etc.) is presented.  相似文献   
8.
9.
A two-dimensional model for quantum-well lasers that solves, self-consistently, the semiconductor equations together with the complex scalar wave equation is described. It incorporates a position- and wavelength-dependent gain function which is derived from a quantum mechanical calculation. Such a model enables one to predict the characteristics of a quantum-well laser with a minimal number of empirical parameters. The output of the model includes light-current characteristics, the current distribution, and the optical field intensity distribution, obtained simultaneously in the calculation. Examples for modeling GRIN-SCH SQW (graded-index separate confinement heterostructure single quantum well) ridge wave guide lasers are given, and good agreement with experimental results is obtained. The model is used to optimize the geometry of a GRIN-SCH SQW laser for minimum threshold current and maximum efficiency  相似文献   
10.
The objective of this study was to evaluate the efficacy, particularly in terms of the 24-hour cover, and the safety of lisinopril 20 mg + hydrochlorothiazide 12.5 mg 5L/HCTZ) and captopril 50 mg + hydrochlorothiazide 25 mg (C/HCTZ) in patients with essential HT requiring two-agent therapy. Twenty patients with a diastolic blood pressure (DBP) between 95 and 120 mmHg after 2 weeks of placebo were randomised to receive, under double-blind conditions, either L/HCTZ or C/HCTZ as a single daily dose for 4 weeks. Clinical examination, laboratory tests and 24-hour ambulatory blood pressure monitoring (ABPM) were performed at the end of the placebo and active treatment periods. L/HCTZ and C/HCTZ significantly lowered SBP and DBP on occasional recordings and on ABPM. The mean fall in blood pressure on ABPM (SBP, DBP, mean of 24-hour recording, diurnal and nocturnal) at 4 weeks was greater with L/HCTZ than with C/HCTZ. Both treatments were effective for 24 hours and did not alter the circadian cycle. The clinical and laboratory safety was good. The blood pressure figures obtained by ABPM were lower than on occasional recordings, emphasising the value of this technique in the evaluation of a patient's poor response to antihypertensive treatment.  相似文献   
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