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1.
A semi‐automated imaging system is described to quantitate estrogen and progesterone receptor immunoreactivity in human breast cancer. The system works for any conventional method of image acquisition using microscopic slides that have been processed for immunohistochemical analysis of the estrogen receptor and progesterone receptor. Estrogen receptor and progesterone receptor immunohistochemical staining produce colorimetric differences in nuclear staining that conventionally have been interpreted manually by pathologists and expressed as percentage of positive tumoral nuclei. The estrogen receptor and progesterone receptor status of human breast cancer represent important prognostic and predictive markers of human breast cancer that dictate therapeutic decisions but their subjective interpretation result in interobserver, intraobserver and fatigue variability. Subjective measurements are traditionally limited to a determination of percentage of tumoral nuclei that show positive immunoreactivity. To address these limitations, imaging algorithms utilizing both colorimetric (RGB) as well as intensity (gray scale) determinations were used to analyze pixels of the acquired image. Image acquisition utilized either scanner or microscope with attached digital or analogue camera capable of producing images with a resolution of 20 pixels /10 μ. Areas of each image were screened and the area of interest richest in tumour cells manually selected for image processing. Images were processed initially by JPG conversion of SVS scanned virtual slides or direct JPG photomicrograph capture. Following image acquisition, images were screened for quality, enhanced and processed. The algorithm‐based values for estrogen receptor and progesterone receptor percentage nuclear positivity both strongly correlated with the subjective measurements (intraclass correlation: 0.77; 95% confidence interval: 0.59, 0.95) yet exhibited no interobserver, intraobserver or fatigue variability. In addition the algorithms provided measurements of nuclear estrogen receptor and progesterone receptor staining intensity (mean, mode and median staining intensity of positive staining nuclei), parameters that subjective review could not assess. Other semi‐automated image analysis systems have been used to measure estrogen receptor and progesterone receptor immunoreactivity but these either have required proprietary hardware or have been based on luminosity differences alone. By contrast our algorithms were independent of proprietary hardware and were based on not just luminosity and colour but also many other imaging features including epithelial pattern recognition and nuclear morphology. These features provide a more accurate, versatile and robust imaging analysis platform that can be fully automated in the near future. Because of all these properties, our semi‐automated imaging system ‘adds value’ as a means of measuring these important nuclear biomarkers of human breast cancer.  相似文献   
2.
A procedure for the prediction of wall-bed heat transfer coefficient for bubble columns and gas-solid fluidized beds is developed on the basis of hydrodynamic behavior of these contactors. A comparison between the predicted and experimental values of heat transfer coefficient over a wide range of design and operating variables is presented. An attempt is made to analyze the occurrence of maxima in heat transfer coefficient with respect to gas velocity in the case of fluidized beds. A procedure for the calculation of the optimum superficial gas velocity is outlined.  相似文献   
3.
Multi-machine, single-inverter induction motor drives are attractive in situations in which all machines are of similar ratings, and operate at approximately the same load torques. The advantages include small size compared to multi-inverter system, lower weight and overall cost. However, field oriented control of such drives is a challenge since no two motors will have exactly the same operating conditions at any time. In general, at least some motors in the system will operate away from perfect field orientation. It is therefore important to analyse their torque dynamics carefully. This paper discusses existing multi-machine field-oriented control methods, and analyses and compares them from the viewpoint of dynamic performance. For this, an analytical framework based on small-signal analysis is developed to compare multi-machine control methods. This analysis is verified by simulations and experiments.  相似文献   
4.
Electronic band structure calculations are performed for the Be x Zn1???x Te (0≤x≤1 in steps of 0·2) alloys following the empirical pseudopotential method. The alloying effects are modelled through the modified virtual crystal approximation. Throughout the composition, valence band maximum resides at the Γ point. The conduction band minimum, however, shifts from Γ to X point of symmetry when x?= 0·27. The observed crossover from direct to indirect bandgap is well in accordance with the experimental observations. Effect of alloying on the density of states is also discussed. The charge density distribution along a few major planes is computed and discussed. The electronic band structure related parameters like bandwidths, bandgaps and ionicity are reported and compared with experimental data wherever available. We also give estimates of cohesive energy and bulk modulus for the alloys.  相似文献   
5.
Thirty‐two Lactobacilli strains were isolated from four samples of camel cheese collected from Bikaner, India. These isolates were identified based on phenotypic and genotypic characteristics. Sequencing of 16S rDNA was performed for species identification and diversity analysis. Lactobacillus delbrueckii and Lb. fermentum were found to be dominant species followed by Lb. plantarum and Lb. casei. On evaluation of technological properties of these isolates, 20 isolates were observed to be good acid producers, eight were found positive for citrate utilisation and 11 showed presence of Prtp gene. Isolates obtained can be potential for development of defined strain starter for camel cheese.  相似文献   
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The influence of ripening temperature and cold conditioning of pre-climacteric fruits on the incidence of chilling injury (CI) in ripe mango fruits cv. Alphonso during refrigerated storage was investigated. Fruits previously held and ripened at tropical ambient temperature (AT, 27–34°C) developed CI (skin staining or browning) when ripe fruits were subsequently stored at 5, 10, or 15°C for shelf-life extension. Fruits held and ripened at 20°C1°C, RH 85–90% showed little evidence of CI when subsequently stored at 5 or 10°C up to 14 days. Chilling injury in ripe mangoes was also avoided by holding pre-climacteric fruits for a minimum period of 30 days at 10°C and then ripening them at 27–34°C. The quality of the ripe mangoes remained good during cold storage for 7 days and were acceptable until 10–14 days with minimal changes in texture, flesh colour, carotenoids, total soluble solids, titratable acids and ascorbic acid. Shelf-life of ripe mangoes can thus be extended under refrigeration by pre-storage conditioning.  相似文献   
9.
The conduction mechanism in Mg2 + and Al3 + substituted Li0.5Fe2.5O4 with general formula MgxAl2xLi0.5(1 − x)Fe2.5(1 − x)O4 (x = 0.0, 0.2, 0.5, 0.6 and 0.7) has been studied by means of compositional and temperature dependent d.c. resistivity, thermoelectric power and I–V characteristics measurements. It is found that ferrites are electronic conductors. For x = 0.0 and 0.2 conduction is due to holes, while for x = 0.5, 0.6 and 0.7 it is due to electrons. Thermal variation of mobilities and activation energies determined through d.c. resistivity measurements confirm the formation of small polarons. The sample with x = 0.0 exhibits switching phenomena.  相似文献   
10.
The promising aspects of nanocomposite coatings to mimic the nano roughened self cleaning surface of lotus leaf is explored in this paper. A detailed study on nanosilica and clay based nanocomposite coatings using dip coating and layer by layer self assembly (L–b–L) is being described where lotus leaf effect has been mimicked on the cotton fabric surface using these particles as they develop nanosized surface roughness which helps to produce a super-hydrophobic surface. Nanosilica performs better in creating nano roughness on cotton fabric wherein the contact angle is ${>}$ 150 $^{\circ}$ . The water contact angle of 2 wt% fluoro emulsion (Nuva HPU) treated cotton fabric increases from 115 $^{\circ}$ to 155 $^{\circ}$ when the fabric is pretreated with 0 ${\cdot} $ 5 wt% nanosilica emulsion. The water repellency rating of fabric treated with 0 ${\cdot }$ 16 wt% nanosilica along with 2 wt% Nuva HPU is comparable to that of 4 wt% Nuva HPU treated cotton fabric. On the other hand, 40 bilayers of nanosilica need to be applied on cotton fabric surface through L–b–L technique to create uniform nano roughening and gives a water repellency rating of 4. The air permeability of L–b–L nanocoated cotton fabric is not adversely affected by the super-hydrophobic nanostructured coating.  相似文献   
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