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81.
BACKGROUND: In the diagnosis of prostate cancer, prostate-specific antigen (PSA) is the most clinically useful tumor marker. Its utility in renal transplant patients is unclear. We hypothesized that PSA values might be affected by the renal function, immunosuppression, or proteinuria. METHODS: Three hundred four PSA values were measured in 166 patients >40 years (53.5 +/- 7.2 years, mean +/- SD, range 44.4 to 76.2). Charts were reviewed for 24-hour creatinine clearance, 24-hour urinary protein, cyclosporine use, age at the time of each PSA test, and evaluation done in response to the PSA result. Analyses used the Mann-Whitney U test and simple regression model. RESULTS: Twenty-five values in 13 patients were >4.0 ng/mL. Of these, 6 patients (6 values) had normal repeat PSA values; 3 patients (11 values) had negative evaluations for prostate cancer; and 4 patients (8 values) were diagnosed with prostate cancer. The latter 4 patients were excluded from the denoted normal group leaving 294 PSA values in 162 patients. The mean normal PSA was 1.3 +/- 1.8 ng/mL, range 0.1 to 20.2. The pretreatment mean PSA for recipients with prostate cancer was 302 +/- 800, range 8.0 to 2,281. An elevated PSA value was associated with a 31% incidence of prostate cancer. There was no association of PSA levels with cyclosporine use, 24-hour creatinine clearance, or 24-hour urinary protein, but there was with age. CONCLUSIONS: Prostate-specific antigen values in renal transplant recipients are similar to those in the general population and are not influenced by cyclosporine or by renal function. We recommend routine measurement of PSA in male transplant recipients.  相似文献   
82.
The activities of CoCl2 in molten MgCl2?KCl at 475° have been determined by measuring the EMF of the galvanic cell.  相似文献   
83.
According to Nyquist's theorem, in the low frequency limit, the thermal noise voltage spectrum can be written as Sv(f) = 4 kTR. Based on this, we can define, RNyquist = Sc(f)/4 kT as the Nyquist resistance of the sample. We can also define the observed zero bias resistance of a sample as Robserved=limV→o (V/I) (V/I). It is common practice to substitute Robserved for RNyquist in order to estimate the thermal noise. It will be shown that this substitution is not always valid in MOSFETs, and that the data obtained by Takagi and van der Ziel can be explained in this manner.  相似文献   
84.
Owing to the revolution in sustainable and green manufacturing the production planning and network design of closed loop supply chain concept has got the attention of researchers and managers. In this paper, a multi-product, multi-facility capacitated closed-loop supply chain framework is proposed in an uncertain environment including reuse, refurbish, recycle and disposal of parts. The uncertainty related to demand, fraction of parts recovered for different product recovery processes, product acquisition cost, purchasing cost, transportation cost, processing, and set-up cost is handled with fuzzy numbers. A fuzzy mixed integer linear programming model is proposed to decide optimally the location and allocation of parts at each facility and number of parts to be purchased from external suppliers in order to maximise the profit of organisation. The proposed solution methodology is able to generate a balanced solution between the feasibility degree and degree of satisfaction of the decision maker. The proposed model has been tested with an illustrative example.  相似文献   
85.
Geotechnical uncertainties may play crucial role in response prediction of a structure with substantial soil-foundation-structure-interaction (SFSI) effects. Since the behavior of a soil-foundation system may significantly alter the response of the structure supported by it, and consequently several design decisions, it is extremely important to identify and characterize the relevant parameters. Moreover, the modeling approach and the parameters required for the modeling are also critically important for the response prediction. The present work intends to investigate the effect of soil and model parameter uncertainty on the response of shallow foundation-structure systems resting on dry dense sand. The SFSI is modeled using a beam-on-nonlinear-winkler-foundation (BNWF) concept, where soil beneath the foundation is assumed to be an assembly of discrete, nonlinear elements composed of springs, dashpots and gap elements. The sensitivity of both soil and model input parameters on shallow foundation responses are investigated using first-order second-moment (FOSM) analysis and Monte Carlo simulation through Latin hypercube sampling technique. It has been observed that the degree of accuracy in predicting the responses of the shallow foundation is highly sensitive soil parameters, such as friction angle, Poisson’s ratio and shear modulus, rather than model parameters, such as stiffness intensity ratio and spring spacing; indicating the importance of proper characterization of soil parameters for reliable soilfoundation response analysis.  相似文献   
86.
Being a fuel of different origin, the standard design parameters of a diesel engine may not be suitable for Jatropha methyl ester (JME). This study targets at finding the effects of the engine design parameters viz. compression ratio (CR) and fuel injection pressure (IP) jointly on the performance with regard to fuel consumption (BSFC), brake thermal efficiency (BTHE) and emissions of CO, CO2, HC, NOx and Smoke opacity with JME as fuel. Comparison of performance and emission was done for different values of compression ratio along with injection pressure to find best possible combination for operating engine with JME. It is found that the combined increase of compression ratio and injection pressure increases the BTHE and reduces BSFC while having lower emissions. For small sized direct injection constant speed engines used for agricultural applications (3.5 kW), the optimum combination was found as CR of 18 with IP of 250 bar.  相似文献   
87.
88.
The Super Instruction Architecture (SIA) is a parallel programming environment designed for problems in computational chemistry involving complicated expressions defined in terms of tensors. Tensors are represented by multidimensional arrays which are typically very large. The SIA consists of a domain specific programming language, Super Instruction Assembly Language (SIAL), and its runtime system, Super Instruction Processor. An important feature of SIAL is that algorithms are expressed in terms of blocks (or tiles) of multidimensional arrays rather than individual floating point numbers. In this paper, we describe how the SIA was enhanced to exploit GPUs, obtaining speedups ranging from two to nearly four for computational chemistry calculations, thus saving hours of elapsed time on large-scale computations. The results provide evidence that the “programming-with-blocks” approach embodied in the SIA will remain successful in modern, heterogeneous computing environments.  相似文献   
89.
Wireless Personal Communications - The deployment of blockchain technologies for multiple use cases has been widely investigated in the academic and business sectors over the last few years. The...  相似文献   
90.
The fatty acid composition of seed oils from yellow-and violet-floweredSesbania sesban varieties was determined. Their composition and properties were too similar to provide chemotaxonomic distinction between the varieties.  相似文献   
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