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1.
Preeclampsia (PE) is a multisystem disorder of pregnancy that develops after 20 wk of gestation in previously normotensive women and complicates 5–8% of pregnancies. This rapidly progressive syndrome is usually diagnosed when the mother develops hypertension and proteinuria. The only effective treatment is delivery of the baby although early low-dose aspirin has been shown to significantly reduce the risk for PE. Recent advances in proteomic methods of protein separation, identification, and quantitation may allow for the identification of proteins and peptides that could facilitate early detection of disease, improve assessment of prognosis, and allow closer monitoring of women at risk for PE. This review summarizes all currently available markers for prediction and diagnosis of PE and presents urine proteomic studies performed for the identification of novel biomarkers.  相似文献   
2.
A method of data acquisition and analysis is described that has been developed to assess in detail the performance of electric arc furnaces. The method has been implemented on a small single user minicomputer (a PDP 11/40) and on a large mainframe (an IBM 3033). The method was specifically developed in order to determine reliable statistical parameters that can be used to characterize arc furnace performance. The method is outlined, and its use is illustrated using data recorded on magnetic tape at the new Iron and Steel Company of Trinidad and Tobago (ISCOTT) plant. Results are presented that illustrate the operation of the ISCOTT furnace for scrap and pellet feed.  相似文献   
3.
Tissue engineering (TE) may provide effective alternative treatment for challenging temporomandibular joint (TMJ) pathologies associated with disc malpositioning or degeneration and leading to severe masticatory dysfunction. Aim of this study was to evaluate the potential of chitosan/alginate (Ch/Alg) scaffolds to promote fibro/chondrogenic differentiation of dental pulp stem cells (DPSCs) and production of fibrocartilage tissue, serving as a replacement of the natural TMJ disc. Ch/Alg scaffolds were fabricated by crosslinking with CaCl2 combined or not with glutaraldehyde, resulting in two scaffold types that were physicochemically characterized, seeded with DPSCs or human nucleus pulposus cells (hNPCs) used as control and evaluated for cell attachment, viability, and proliferation. The DPSCs/scaffold constructs were incubated for up to 8 weeks and assessed for extracellular matrix production by means of histology, immunofluorescence, and thermomechanical analysis. Both Ch/Alg scaffold types with a mass ratio of 1:1 presented a gel-like structure with interconnected pores. Scaffolds supported cell adhesion and long-term viability/proliferation of DPSCs and hNPCs. DPSCs cultured into Ch/Alg scaffolds demonstrated a significant increase of gene expression of fibrocartilaginous markers (COLI, COL X, SOX9, COM, ACAN) after up to 3 weeks in culture. Dynamic thermomechanical analysis revealed that scaffolds loaded with DPSCs significantly increased storage modulus and elastic response compared to cell-free scaffolds, obtaining values similar to those of native TMJ disc. Histological data and immunochemical staining for aggrecan after 4 to 8 weeks indicated that the scaffolds support abundant fibrocartilaginous tissue formation, thus providing a promising strategy for TMJ disc TE-based replacement.  相似文献   
4.
Transactions of the Indian Institute of Metals - A stepped heating cycle in a tube furnace at 1000 °C for 1 h followed by holding at 400 °C for 1 h...  相似文献   
5.
Portunid crabs of the genus Portunus: P. pelagicus, P. gladiator and P. sanguinolentus and the genus Charybdis: C. natator and C. feriatus are economically important species for many tropical countries. An ongoing problem in the crab industry is involved with food labelling or food fraud in which many food manufacturers may have substituted the cheaper crabmeat for the more expensive ones due to the difficulty of species identification after many steps of food processing. To solve this problem, a convenient and accurate multiplex PCR assay using a species-specific primer set KUGEN_PORTspec was developed based on the nucleotide variation of cytochrome b and 28S ribosomal RNA. The primer set specifically amplified fragments of 286, 348, 418, 124 and 481 bp in P. pelagicus, P. gladiator, P. sanguinolentus, C. natator and C. feriatus, respectively, as well as a 220 bp positive control fragment. Specificity and sensitivity tests showed consistency in product sizes and absence of cross-species amplification with 0.1 ng DNA template limit of detection. Validation of the multiplex PCR assay on crabmeat prepared by steaming, mixing, freezing and canning was done and visualized by either agarose gel electrophoresis or automated capillary electrophoresis. The results indicated that the multiplex PCR assay using KUGEN_PORTspec is an effective tool for portunid species identification from both high- and low-quality DNA obtained from processed food. This newly developed primer set is an effective tool for crabmeat species identification to be used in future food industry and consumer protection programs.  相似文献   
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The effect of flank wear on the topography of machined surfaces is investigated by studying its effect on the shape of the tool nose. For this purpose, turning experiments were performed to produce surfaces corresponding to different levels of flank wear. The distribution of flank wear at the tool nose during these experiments caused the nose radius to decrease, which when replicated on the machined surface resulted in narrower and deeper feedmarks. This change in the geometry of feedmarks was represented by the increase in the arithmetic average roughness of the surface profile heights.  相似文献   
8.
Fouling is one of the main problems of heat transfer which can be described as the accumulation on the heat exchanger tubes, i.e.; ash deposits on the heat exchanger unit of the boiler. A decrease in heat transfer rate by this deposition causes loss in system efficiency and leads to increasing in operating and maintenance costs. This problem concerns with the coupling among conduction heat transfer mode between solid of different types, conjugate heat transfer at the interface of solid and fluid, and the conduction/convection heat transfer mode in the fluid which can not be solved analytically. In this paper, fouling effect on heat transfer around a cylinder in cross flow has been studied numerically by using conjugate heat transfer approach. Unlike other numerical techniques in existing literatures, an unstructured control volume finite element method (CVFEM) has been developed in this present work. The study deals with laminar flow where the Reynolds number is limited in the range that the flow field over the cylinder is laminar and steady. We concern the fouling shape as an eccentric annulus with constant thermal properties. The local heat transfer coefficient, temperature distribution and mean heat transfer coefficient along the fouling surface are given for concentric and eccentric cases. From the results, we have found that the heat transfer rate of cross-flow heat exchanger depends on the eccentricity and thermal conductivity ratio between the fouling material and fluid. The effect of eccentric is dominant in the region near the front stagnation point due to high temperature and velocity gradients. The mean Nusselt number varies in asymptotic fashion with the thermal conductivity ratio. Fluid Prandtl number has a prominent effect on the distribution of local Nusselt number and the temperature along the fouling surface.  相似文献   
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We propose a new technique for analyzing the raw neurogram which enables the study of the discharge behavior of individual and group neurons. It utilizes an ideal bandpass filter, a modified wavelet de-noising procedure, an action potential detector, and a waveform classifier. We validated our approach with both simulated data generated from muscle sympathetic neurograms sampled at high rates in five healthy subjects and data recorded from seven healthy subjects during lower body negative pressure suction. The modified wavelet method was superior to the classical discriminator method and the regular wavelet de-noising procedure when applied to simulated neuronal signals. The detected spike rate and spike amplitude rate of the action potentials correlated strongly with number of bursts detected in the integrated neurogram (r = 0.79 and 0.89, respectively, p < 0.001). Eight major action potential waveform classes were found to describe more than 81% of all detected action potentials in all subjects. One class had characteristics similar in shape and in average discharge frequency (27.4 +/- 5.1 spikes/min during resting supine position) to those of reported single vasoconstrictor units. The newly proposed technique allows a precise estimate of sympathetic nerve activity and characterization of individual action potentials in multiunit records.  相似文献   
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