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81.
Hypothermic coagulopathy in trauma: effect of varying levels of hypothermia on enzyme speed, platelet function, and fibrinolytic activity 总被引:1,自引:0,他引:1
DD Watts A Trask K Soeken P Perdue S Dols C Kaufmann 《Canadian Metallurgical Quarterly》1998,44(5):846-854
Comparative study of protein metabolism in neurons of layers III and V of the sensorimotor cortex was carried out in two groups of Wistar rats, which differed in learning results: "bad" (60% of population) and "good" learners (40%). It was found out that the associative neurons (layer III) were most sensitive to cognitive load. In "bad" learners, an increase in nuclear and cytoplasmic dimensions and rise in protein concentration and content took place in these neurons, while in the efferent neurons (layer V) the protein content increased only in the cytoplasm. In "good" learners, the cognitive load led to a decrease in all the cytochemical parameters in neurons of the layer III while in the neurons of the layer V the content and concentration of proteins increased both in nuclei and cytoplasm. It is suggested that the character of protein metabolism changes produced by information load can be considered as a reflection of individual peculiarities of cognitive activity, and the extent of cytochemical changes as a reflection of complicity of a cognitive task. 相似文献
82.
Measurement of transient deformations with dual-pulse addition electronic speckle-pattern interferometry 总被引:3,自引:0,他引:3
We describe an electronic speckle-pattern interferometry system for analyzing addition fringes generated by the transient deformation of a test object. The system is based on a frequency-doubled twin Nd:YAG laser emitting dual pulses at a TV camera field rate (50 Hz). The main advance has been the automatic, quantitative analysis of dual-pulse addition electronic speckle-pattern interferometry data by the introduction of carrier fringes and the application of Fourier methods. The carrier fringes are introduced between dual pulses by a rotating mirror that tilts the reference beam. The resulting deformation-modulated addition fringes are enhanced with a deviation filter, giving fringe visibility close to that of subtraction fringes. The phase distribution is evaluated with a Fourier-transform method with bandpass filtering. From the wrapped phase distribution, a continuous phase map is reconstructed with an iterative weighted least-squares unwrapper. Preliminary results for a thin plate excited by an acoustic shock show the suitability of the system for the quantitative evaluation of transient deformation fields. 相似文献
83.
Unwrapping of Digital Speckle-Pattern Interferometry Phase Maps by use of a Minimum L(0)-Norm Algorithm 总被引:1,自引:0,他引:1
The performance of a minimum L(0)-norm unwrapping algorithm is investigated by use of synthetic digital speckle-pattern interferometry (DSPI) wrapped phase maps that simulate experimentally obtained data. This algorithm estimates its own weights to mask inconsistent pixels. Particular features usually included in DSPI wrapped phase distributions, such as shears, speckle noise, fringe cuts, object physical limits, and superimposed phase maps, are analyzed. Some adequate approaches to solving these features are discussed. Finally, it is shown that a complex case in which shears and fringe cuts coexist in the wrapped phase cannot be solved satisfactorily with the minimum L(0)-norm algorithm by itself. To cope with this problem, we propose a new scheme. 相似文献
84.
GW Gao SH Lin YF Lin LK Diang KC Lu FC Yu SD Shieh 《Canadian Metallurgical Quarterly》1996,57(6):438-442
Despite a general national decline in criminal activities in the 1990s, juvenile criminal offenses continue to increase, (including violent, property, and delinquency acts). In addition increased numbers of children are being held in juvenile jails. It is all but impossible for pediatric health providers to think that "their patients" and "their practices" are immune from the epidemic of crime that affects and is caused by "just kids." 相似文献
85.
SH Selesnick MT Abraham JF Carew 《Canadian Metallurgical Quarterly》1996,17(5):793-805; discussion 806-9
Anterior rerouting of the intratemporal facial nerve in the infratemporal fossa approach is employed to access to the jugular bulb, hypotympanum, and lateral skull base, whereas posterior rerouting of the facial nerve, as employed in the transcochlear craniotomy, is most frequently used for surgery of the posterior fossa, cerebellopontine angle, prepontine region, and petrous apex. Facial nerve rerouting may lead to facial paresis or paralysis. This review of the literature is intended to define the physiologic "cost" of these procedures, so that the neurotologic surgeon can determine if the morbidity incurred in these techniques is worth the resultant exposure. Inconsistencies in reporting facial function places into question the validity of some of the cumulative data reported. Postoperatively, grades I-II facial nerve function was seen in 91% of patients undergoing short anterior rerouting, 74% of patients undergoing long anterior rerouting, and 26% of patients undergoing posterior complete rerouting. Although facial nerve rerouting allows unhindered exposure to previously inaccessible regions, it is achieved at the cost of facial nerve function. Facial nerve dysfunction increases with the length of facial nerve rerouted. 相似文献
86.
The need to make the contents of the Semantic Web accessible to end-users becomes increasingly pressing as the amount of information stored in ontology-based knowledge bases steadily increases. Natural language interfaces (NLIs) provide a familiar and convenient means of query access to Semantic Web data for casual end-users. While several studies have shown that NLIs can achieve high retrieval performance as well as domain independence, this paper focuses on usability and investigates if NLIs and natural language query languages are useful from an end-user's point of view. To that end, we introduce four interfaces each allowing a different query language and present a usability study benchmarking these interfaces. The results of the study reveal a clear preference for full natural language query sentences with a limited set of sentence beginnings over keywords or formal query languages. NLIs to ontology-based knowledge bases can, therefore, be considered to be useful for casual or occasional end-users. As such, the overarching contribution is one step towards the theoretical vision of the Semantic Web becoming reality. 相似文献
87.
Markus Kaufmann Dan Zenkert Per Wennhage 《Structural and Multidisciplinary Optimization》2010,41(2):325-334
A methodology for a combined cost/weight optimization of aircraft components is proposed. The objective function is formed
by a simplified form of direct operating cost, i.e. by a weighted sum of the manufacturing cost and the component weight.
Hence, the structural engineer can perform the evaluation of a design solution based on economical values rather than pure
cost or weight targets. The parameter that governs the balance between manufacturing cost and weight is called weight penalty
and incorporates the effect of fuel burn, environmental impact or contractual penalties due to overweight. Unlike previous
work, the analytical cost model and structural models are replaced by commercially available software packages that allow
a more realistic model of the manufacturing costs; further, arbitrary constraints for the structural analysis can be implemented.
By means of parametric studies it is shown that the design solution strongly depends on the magnitude of the weight penalty. 相似文献
88.
89.
Gaucher's disease is a lysosomal storage disease in which cells of the reticuloendothelial system accumulate the lipid glucocerebroside. It is characterized by slowly progressive visceral and osseous involvement. One of the latter manifestations includes lipid infiltration of bone marrow. We monitored the rate of inhaled 133Xe uptake and wash-out over diseased and normal metaphyseal and epiphyseal areas of the knee. Twenty-two patients (15 adults, 7 children) with various degrees of previously diagnosed Gaucher's disease were positioned supine under a gamma-camera interfaced to a computer system. All patients rebreathed 133Xe gas from a closed system for 10 min followed by 14 min of wash-out. Digitized images of the lung, liver, spleen, bony sites and soft tissue were obtained at 1 min intervals during the wash-in and wash-out phases. Counts for each ROI were normalized per 100 pixels and plotted as a function (time). Maximum uptake was also calculated by relating the counts/ROI/100 pixels to the 10 min integrated lung count during equilibrium (the administered "dose"). There was essentially no 133Xe uptake in liver and spleen involved with Gaucher's disease. Monophasic uptake and biphasic wash-out curves were observed in the limited investigative population. Skeletal Gaucher deposits released the 133Xe at a greater rate relative to soft tissue. 相似文献
90.
Nitrous oxide produced a dose-related "analgesia" in mice (median effective dose, 55 percent). The analgesia was evaluated by means of a phenylquinone writhing test. Narcotic antagonists or chronic morphinization reduced nitrous oxide analgesia. Either nitrous oxide releases an endogenous analgesic or narcotic antagonists have analgesic antagonist properties heretofore unappreciated. 相似文献