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71.
The non‐surgical diagnosis of endometriosis is still challenging for the clinician. Ultrasonography and magnetic resonance imaging can be used to diagnose ovarian endometriotic cysts and deep infiltrating endometriosis; but their performance is poor in the diagnosis of initial stages of endometriosis. CA‐125 and other serum markers (such as CA 19‐9, serum protein PP14, interleukins, and angiogenetic factors) have been measured in women with endometriosis but they are not reliable for the diagnosis of the disease. Although several studies used proteomics technologies to identify plasmatic markers of endometriosis, the non‐invasive diagnosis of endometriosis is far from being achieved. In this issue, Manousopoulou et al. compare the integrated quantitative proteomic profile of eutopic endometrium and serum of women with endometriosis and controls. 1214 proteins are differentially expressed in the eutopic endometrium and 404 proteins in the serum of the two study groups. 21 proteins are aberrantly expressed in both eutopic endometrium and serum of women with endometriosis. More work is needed to assess if the differentially expressed proteins identified in this study can be used as clinical markers of endometriosis.  相似文献   
72.
We give a simple direct proof of the Jamiołkowski criterion to check whether a linear map between matrix algebras is completely positive or not. This proof is more accessible for physicists than other ones found in the literature and provides a systematic method to give any set of Kraus matrices of the Kraus decomposition.Presented at the 36th Symposium on Mathematical Physics, “Open Systems & Quantum Information”, Toruń, Poland, June 9-12, 2004.  相似文献   
73.
74.
Electrophysiologic models of heart cells and cell networks   总被引:5,自引:0,他引:5  
This article summarizes the basic principles of action potential models, reviews the development of cellular models of normal and diseased cells, and discusses some important contributions of computer simulations to the understanding of arrhythmia generation in heart-cell networks. The article should enable a better understanding of arrhythmias and heart disease  相似文献   
75.
A new versatile tool, combining Shear Force Microscopy and X-Ray Spectroscopy was designed and constructed to obtain simultaneously surface topography and chemical mapping. Using a sharp optical fiber as microscope probe, it is possible to collect locally the visible luminescence of the sample. Results of tests on ZnO and on ZnWO4 thin layers are in perfect agreement with that obtained with other conventional techniques. Twin images obtained by simultaneous acquisition in near field of surface topography and of local visible light emitted by the sample under X-Ray irradiation in synchrotron environment are shown. Replacing the optical fibre by an X-ray capillary, it is possible to collect local X-ray fluorescence of the sample. Preliminary results on Co-Ti sample analysis are presented.  相似文献   
76.
BACKGROUND: Membrane bioreactors are used in an increasing number of wastewater treatment facilities because of their compactness and efficiency in solid‐liquid separation, but energy requirements are still higher than other competitive technologies such as conventional activated sludge. RESULTS: In this paper the development of an air‐scour control algorithm based on short‐term and long‐term membrane permeability evolution is presented. An open loop calibration and partial validation was carried out in a semi‐industrial scale pilot plant where manual changes in air‐scour flow had been previously carried out. The control system was successfully tested in closed loop in an industrial scale pilot plant, defining a maximum daily air‐scour decrease or increase of 6% of the air‐scour recommended by membranes suppliers. An average air‐scour saving of 13% and a maximum of 20%, calculated in terms of air flow saved, were achieved during the validation test without any apparent long‐term effect on membrane permeability. CONCLUSION: It was proven that the air‐scour control system is an important tool capable of reducing operational costs in MBR systems. Copyright © 2011 Society of Chemical Industry  相似文献   
77.
The in situ polymerisation of acrylic acid using low temperature plasma treatment was carried out on polyester, polyamide and polypropylene fabrics with the aim of improving their dyeability with basic dyes. The overall colour strength obtained was significantly increased as a result of this treatment. However, while the wash fastness was acceptable on polyamide, it was unsatisfactory on polyester and polypropylene fabrics, probably due to lack of penetration of these fibres by the acrylic acid monomer. Scanning electron microscopy and Fourier transform infrared spectroscopy confirmed that grafting of polyacrylic acid had taken place only on the surface of the polyester and polypropylene fibres, but in the case of polyamide the interior of the fibre was also modified.  相似文献   
78.
The determination of the characteristics of the variable reluctance motors (both in static and dynamic conditions) represents a quite critical point, due to the heavy nonlinearity of the motor magnetic paths, to the high distortion of the supply voltage from the converter, and to the high level of saturation of the magnetic paths in normal working conditions. This creates a great difficulty in the accurate measurement of the motor magnetic characteristics (saturation curves or flux linkage versus current curves) and consequently in the determination of the mechanical characteristics (static torque versus current and static torque versus rotor position) which are directly related to the saturation curves. The paper proposes an original digital method that, starting from the measurement of the flux linkage in the motor magnetic paths, determines the saturation curves, evaluates the coenergy versus current curves and then the motor torque characteristics in static conditions. It is then shown how the availability of a fast and accurate method for the measurement of the flux linkage allows the determination of the electromagnetic torque in dynamic conditions, too  相似文献   
79.
The cell lethality and permeability induced in Escherichia coli B/r and Escherichia coli BS-1 by 60Co gamma-ray irradiation, ultrasound and hyperthermia in media containing different concentrations of NaCl have been investigated. It was shown that independently from the nature of damaging factors hypotonic media increase while hypertonic media in certain range of osmolyte concentration decrease sensitivity of cells to action of this factors. It was proposed that discovered phenomenology was caused by salt modification of status of the cell osmotic homeostasis destabilizing by ionizing radiation, ultrasound or hyperthermia and was not related with the system of dark repair of DNA.  相似文献   
80.
In recent years the introduction of serum prostate-specific antigen (PSA) determination as a screening tool for early detection of prostate cancer in asymptomatic men has led to a markedly increased detection of prostate cancers that are neither palpable nor visible with transrectal ultrasonography (stage T1c). In this preliminary study we assessed pathologic features and aspects that are indicative of clinical significance in T1c tumors and tumors with palpable or visible lesions (non-T1c tumors). Between June 1994 and December 1995, 51 consecutive radical prostatectomies were performed on screened participants in the Rotterdam section of the European Randomized Study of Screening for Prostate Cancer (ERSPC). After determination of pathologic stage and Gleason score, morphometric analysis was performed to determine tumor volume. Radical prostatectomy specimens were divided into three mutually exclusive subsets: T1c tumors, non-T1c tumors with preoperative PSA levels below 4 ng/ml, and non-T1c tumors with PSA levels equal to or greater than 4 ng/ml. These subsets were compared for differences in the distribution of tumor volume, pathologic stage, and Gleason score. An arbitrarily constructed categorization model was used to assess clinical significance. In all, 17 (33%) of the patients had clinical stage T1c disease. In our categorization mode, 88% of the T1c tumors fit the criteria for clinically significant tumors. T1c tumors, however, were significantly smaller (P < 0.01) and were more likely to be organ-confined (P = 0.01) as compared with non-T1c tumors in patients with an elevated preoperative serum PSA level. In contrast, tumors detected at preoperative PSA levels of < 4 ng/ml had comparably the lowest pathologic stages and tumor volumes in our series. In our categorization model, 42% of these tumors fit the criteria for minimal tumor. This group of radical prostatectomies was therefore most likely to harbor clinically insignificant cancer, a finding that was consistent in two other categorization models derived from earlier reports. T1c tumors comprise a large fraction of the tumors found in population-based screening. As judged by their pathologic characteristics. T1c tumors are clinically significant tumors. The overall low pathologic stage and Gleason score of these tumors make these patients excellent candidates for curative treatment by radical prostatectomy or radiotherapy. In contrast, some concern should be raised on the detection of tumors at low serum PSA levels by means of digital rectal examination and transrectal ultrasound alone, since a substantial proportion of these tumors could be considered clinically insignificant. Long-term follow-up, however, is necessary to substantiate this view.  相似文献   
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