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81.
Bone metastasis is a complex process that needs to be better understood in order to help clinicians prevent and treat it. Xenografts using patient-derived material (PDX) rather than cancer cell lines are a novel approach that guarantees more clinically realistic results. A primary culture of bone metastasis derived from a 67-year-old patient with breast cancer was cultured and then injected into zebrafish (ZF) embryos to study its metastatic potential. In vivo behavior and results of gene expression analyses of the primary culture were compared with those of cancer cell lines with different metastatic potential (MCF7 and MDA-MB-231). The MCF7 cell line, which has the same hormonal receptor status as the bone metastasis primary culture, did not survive in the in vivo model. Conversely, MDA-MB-231 disseminated and colonized different parts of the ZF, including caudal hematopoietic tissues (CHT), revealing a migratory phenotype. Primary culture cells disseminated and in later stages extravasated from the vessels, engrafting into ZF tissues and reaching the CHT. Primary cell behavior reflected the clinical course of the patient’s medical history. Our results underline the potential for using PDX models in bone metastasis research and outline new methods for the clinical application of this in vivo model.  相似文献   
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During flights, reduced odor and taste perception is reported. Passengers tend to prefer spicier meals than on the ground. The conditions on board were simulated at the Fraunhofer flight test facility in Holzkirchen, Germany, consisting of a front fuselage of an Airbus A310-200 in a huge metal tube in which all relevant parameters can be adjusted (humidity, temperature, pressure). Flight tests were carried out at low atmospheric pressure corresponding to cabin conditions on board at cruising altitude and were repeated at normal atmospheric pressure corresponding to ground conditions. All other parameters were kept constant. Under these conditions, test persons smelled and tasted food-safe flavorants to evaluate the mean odor and taste thresholds and tasted different flavored food. Even tomato juice and various wines were tasted for odor and taste qualities, intensities and individual preferences. At low pressure conditions, higher taste and odor thresholds of flavorants were generally observed with few exceptions. Salt, sugar, glutamate and most odorant thresholds increased clearly. Organic acids and some bitter tastants showed no change. Transferred to complete meals, more salt, sugar and herbs were necessary on board to serve meals that tasted similar to the way they did on the ground. Sour ingredients had to be reduced. The odor and taste spectrum of the beverages investigated changed in various ways. Light and fresh flavors decreased, whereas intensive flavors persisted.  相似文献   
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A nonlinear constitutive equation has been proposed to describe the dependence of the cross‐link density vs. peroxide and coagent concentrations, following the dynamic vulcanization of ethene‐propene copolymers (EPM) rubbers. This was obtained by integrating the rate equations of the fundamental reactions of the cross‐linking processes (β‐scission, chemical coupling, coagent grafting). The compression set test ASTM D 395 was then modeled and put in correlation with the cross‐linking density. The model was then validated with compression set experimental data, obtained from a series of EPM rubbers dynamically cross‐linked under various conditions of peroxide/coagent content. The two most meaningful model parameters (N1 and N2, which are linked to the order of the rate equations) have been correlated with the elastomer microstructure, particularly with the ethene intramolecular chain distribution and content. POLYM. ENG. SCI., 45:333–342, 2005. © 2005 Society of Plastics Engineers  相似文献   
86.
The aim of this study was to evaluate possible associations between three SNPs at the oxytocin locus (AM234538: g.28C>T; g.204A>G and g.1627G>T) and two productive traits, milk yield and milkability, in Italian Mediterranean river buffaloes. Effects of parity, calving season and month of production were also evaluated. A total of 41 980 test-day records belonging to 219 lactations of 163 buffalo cows were investigated. The allele call rate was 98·8% and the major allele frequency for all the investigated loci was 0·76. The OXT genotype was significantly associated with milk yield (P=0·029). The TT genotype showed an average daily milk yield approximately 1·7 kg higher than GT buffaloes. Such a difference represents about 23% more milk/d. A large dominance effect (-1·17±0·43 kg) was estimated, whereas the contribution of OXT genotype (r(2)(OXT)) to the total phenotypic variance in milk yield was equal to 0·06. The TT genotype showed higher values also for the milk flow, even though the estimated difference did not reach a level of statistical significance (P=0·07). Such an association, among the first reported for the oxytocin locus in ruminants, should be tested on a population scale and possible effects on milk composition traits should be evaluated in order to supply useful indications for the application of marker-assisted selection programmes in river buffaloes.  相似文献   
87.
This work was aimed to determine the effect of fermentation and drying on the content and profile of procyanidins (from monomers P1 to polymers P10) as well as on the antiradical and scavenging properties of cocoa beans. To this purpose, three experiments were carried out: a traditional fermentation process followed by air drying and two pilot-scale fermentation processes by either natural microbiota or starter followed by sun drying. Procyanidins were evaluated by HPLC analysis, while the total polyphenol index (TPI), the antiradical activity as well as the reducing power were determined by means of the reaction with the Folin–Ciocalteu reagent, the decolorization assays of the ABTS radical (TEAC) and the Ferric Reducing Antioxidant Power (FRAP) methods, respectively. Both the traditional and pilot-scale processes resulted to affect the profile and content of the procyanidins fractions as well as the antiradical and reducing power functionality. Drying caused a severe reduction of compounds and thus resulted to be the critical step for the loss of procyanidins and monomers in particular. The indices of functionality generally showed a decreasing trend as a consequence of processing, and their evolution was similar to that observed in procyanidins content. To study the relationship between the individual procyanidins and the antioxidant activity expressed as TEAC, FRAP and TPI, the data set were processed by modified partial least squares regression. The obtained models presented a good predictive ability. Normalised regression coefficients showed that the relative contribution of each single class of compounds to total antioxidant activity resulted as follows: P1?>?P2?>?P3?>?P4?>?P6?>?P8?>?P5?>?P7?>?P9?>>?P10.  相似文献   
88.
A general strategy for controlling particle movement across streams would enable new capabilities in single-cell analysis, solid-phase reaction control, and biophysics research. Transferring cells across streams is difficult to achieve in a well-controlled manner, since it requires precise control of fluid flow along with external force fields or precisely manufactured mechanical structures. Herein a strategy is introduced for particle transfer based on passive inertial lift forces and shifts in the distribution of these forces for channels with shifting aspect ratios. Uniquely, use of the dominant wall-effect lift parallel to the particle rotation direction is explored and utilized to achieve controllable cross-stream motion. In this way, particles are positioned to migrate across laminar streams and enter a new solution without significant disturbance of the interface at rates exceeding 1000 particles per second and sub-millisecond transfer times. The capabilities of rapid inertial solution exchange (RInSE) for preparation of hematological samples and other cellular assays are demonstrated. Lastly, improvements to inline flow cytometry after RInSE of excess fluorescent dye and focusing for downstream analysis are characterized. The described approach is simply applied to manipulating cells and particles and quickly exposing them to or removing them from a reacting solution, with broader applications in control and analysis of low affinity interactions on cells or particles.  相似文献   
89.
The antioxidant activity of seven apple varieties was determined on fresh fruits and processed products (dried fruits and purees) and during storage. The antioxidant activity of apples correlated with the total phenol concentration but not with ascorbic acid concentration. Apple derivatives showed a lower antioxidant activity than the counterparts of the fresh fruits and the occurrence of browning phenomena during processing resulted in lower antioxidant activity. Dried fruits showed higher antioxidant activity per gram of dried matter than fruit purees probably because of the lower total thermal effect of processing. The antioxidant activity of all products increased within the first month of storage, and then declined. The extent of early increase was related to the polyphenol content of the fruit. Packaging conditions further influenced the antioxidant activity increase during storage possibly by affecting the oxygen availability.  相似文献   
90.
A range of reactor grade TPO alloys (PP/EPM alloys from Ziegler‐Natta catalysis) were studied in order to evaluate their dynamic cross‐linkability, using a peroxide system. The amount of ethylene content in EPM rubber ranged from 28 to 77 wt%, to investigate the competition between vis‐breaking and cross‐linking during the peroxide reaction. Processing temperature and different peroxide/coagent ratios were the parameters varied in the present work. Cross‐linking degree was evaluated with Compression Set measurements and Dynamic Mechanical Analysis. It was therefore possible to find a correlation between the two analytical techniques. Feasibility of TPV rubbers with Compression Set at about 50% (22 h, 70°C) was demonstrated.  相似文献   
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