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31.
OBJECTIVE: To confirm whether patients with polycystic ovary syndrome (PCOS) have a reduction in uterine perfusion and to verify whether chronic administration of cabergoline can decrease this high vascular resistance. DESIGN: Prospective randomized trial. SETTING: Endocrinological Centre of the Department of Obstetrics and Gynecology, University of Cagliari, Cagliari, Italy. PATIENT(S): Thirty patients were enrolled in the study: 20 affected by PCOS and 10 healthy controls. Patients with PCOS were randomly assigned to one of two treatments for 3 months: oral administration of cabergoline (0.5 mg) every week or oral administration of placebo every week. INTERVENTION(S): All patients underwent transvaginal ultrasonography associated with Doppler flow measurement of the uterine artery, and serum hormone concentrations were determined during the early follicular phase. In women with PCOS, Doppler flow measurement and hormonal assessment were repeated in the early follicular phase of the third month of treatment. MAIN OUTCOME MEASURE(S): Pulsatility index of the uterine artery before and during treatment. RESULT(S): The mean pulsatility index of the uterine artery in patients with PCOS was significantly higher than that of the control group (3.29+/-0.5 and 2.01+/-0.2, respectively). Patients with PCOS treated with cabergoline showed a significant increase in uterine perfusion, with a pulsatility index of 3.14+/-0.6 before and 2.39+/-0.5 during the treatment. No difference was found in patients with PCOS treated with placebo. CONCLUSION(S): Patients with PCOS have high resistance in the uterine arteries, but chronic administration of cabergoline can increase uterine perfusion.  相似文献   
32.
Hydrodemetallation catalysts typically become inactive by pore mouth plugging, leaving a portion of the catalyst in the interior unutilized. By designing the pore size distribution so as to accommodate larger amount of metal deposit, improved performance can be attained. In this work the effect of nonuniform radial pore size distribution on catalyst performance is explored theoretically. Under the constraints of fixed total internal surface area and local void fraction, it is shown that catalysts with linear radial pore size distribution have larger metal deposit capacity. Furthermore, plugging of the pore mouth is delayed and therefore catalyst lifetime also increases.  相似文献   
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This paper explores the networks of thoughts behind words by reading architectural texts in the context of linguistics. Using a corpus-based model, our main interest is what the collocational data contribute at an architectural level. The notion of “collocation identification in architecture” was drawn from an analysis of the use of the data for Rem Koolhaas. The data for this study were collected from Rem Koolhaas’s articles from 1977 to 2014. An analysis of Koolhaas’s ideas about architecture and urban planning was conducted using the AntConc 3.4.4.0 corpus analysis toolkit. The corpus-based model reduced selected articles to words and lexical bundles using the corpus analysis toolkit. This paper explores Koolhaas’s thoughts on understanding architecture and the metaphors he uses by analyzing articles using the corpus-based analysis model. The discourse codes in the texts of Koolhaas are examined. A corpus-based model proposal tested on architectural texts has the potential to create new areas of knowledge for architectural discourse. Deciphering the texts and analyzing the codes contribute to the development of new models.  相似文献   
35.
In this article, we present (1) a feature selection algorithm based on nonlinear support vector machine (SVM) for fault detection and diagnosis in continuous processes and (2) results for the Tennessee Eastman benchmark process. The presented feature selection algorithm is derived from the sensitivity analysis of the dual C-SVM objective function. This enables simultaneous modeling and feature selection paving the way for simultaneous fault detection and diagnosis, where feature ranking guides fault diagnosis. We train fault-specific two-class SVM models to detect faulty operations, while using the feature selection algorithm to improve the accuracy and perform the fault diagnosis. Our results show that the developed SVM models outperform the available ones in the literature both in terms of detection accuracy and latency. Moreover, it is shown that the loss of information is minimized with the use of feature selection techniques compared to feature extraction techniques such as principal component analysis (PCA). This further facilitates a more accurate interpretation of the results. © 2018 American Institute of Chemical Engineers AIChE J, 65: 992–1005, 2019  相似文献   
36.
The present investigation is an experimental study of the mixing of two phases of strongly different viscosity in a co‐rotating twin‐screw extruder (TSE). Two cases were considered: a miscible (copolymer of ethylene and vinyl acetate/bis(2‐ethylhexyl)phtalate [EVA/DOP]) and an immiscible (EVA/ethylene‐glycol [EVA/EG]) binary system. The residence time distribution (RTD) has been determined for each phase of both systems for different screw profiles and different operating conditions. The behavior of the first system is simple: the type of flow is basically the same. However, in the case of nonmiscibility, when the flow rate is high, the shape of the RTD of both phases may be different. We interpret this result with the appearance of a lubrication phenomenon. POLYM. ENG. SCI., 45:926–934, 2005. © 2005 Society of Plastics Engineers  相似文献   
37.
Proof planning is an application of AI planning to theorem proving that employs plan operators that encapsulate mathematical proof techniques. Many proofs require the instantiation of variables; that is, mathematical objects with certain properties have to be constructed. This is particularly difficult for automated theorem provers if the instantiations have to satisfy requirements specific for a mathematical theory, for example, for finite sets or for real numbers, because in this case unification is insufficient for finding a proper instantiation. Often, constraint solving can be employed for this task. We describe a framework for the integration of constraint solving into proof planning that combines proof planners and stand-alone constraint solvers. Proof planning has some peculiar requirements that are not met by any off-the-shelf constraint-solving system. Therefore, we extended an existing propagation-based constraint solver in a generic way. This approach generalizes previous work on tackling the problem. It provides a more principled way and employs existing AI technology.  相似文献   
38.
Chimpanzees (Pan troglodytes) competed with a human for food. The human sat inside a booth, with 1 piece of food to her left and 1 to her right, which she could retract from her chimpanzee competitor's reach as needed. In Experiment 1, chimpanzees could approach either side of the booth unseen but then had to reach through 1 of 2 tunnels (1 clear, 1 opaque) for the food. In Experiment 2, both tunnels were clear and the human was looking away, but 1 of the tunnels made a loud noise when it was opened. Chimpanzees preferentially reached through the opaque tunnel in the first study and the silent tunnel in the second, successfully concealing their taking of the food from the human competitor in both cases. These results suggest that chimpanzees can, in some circumstances, actively manipulate the visual and auditory perception of others by concealing information from them. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
39.
The sensitivity and electrophysiological patterns of paroxysmal activity induced in different brain structures by topical application of penicillin-G were evaluated in the rat. Recordings were carried out in five groups of animals, in telencephalon, diencephalon, mesencephalon, rombencephalon and spinal cords. The following analysis were carried out: frequency distribution histograms, latency and time course duration of paroxysmal activity, duration and amplitude of epileptic bursts. The results obtained showed that the nervous structures tested with penicillin-G had a different epileptogenic sensitivity and response pattern which significantly changed along the cerebral cortex-spinal cord axis. The highest epileptic sensitivity was observed in somatosensory cortex (SI) at 500-600 microns depth; in the other cortical layers, a significant lenghtening in latency was observed. Among the other structures, the spinal cord seemed to be the most sensitive target to the epileptogenic action of penicillin-G, whereas in the remaining structures, sensitivity significantly decreased in rostro-caudal direction. As far as the features of the paroxysmal activity are concerned, significant differences among tested structures were observed. In particular, within the SI cortex, the main differences were represented by the gradual increase in burst frequency and voltage from the surface to the IVth layer and by their subsequent decrease in deeper layers (V-VI). In the diencephalon, the paroxysmal activity was similar to that observed in more superficial and deeper cortical layers even though epileptic bursts showed a lower amplitude. Mesencephalon and rombencephalon displayed a paroxysmal activity with a distinctive feature, characterized by long lasting bursts of low amplitude, although bulbar outbursts showed a shorter duration than the mesencephalic ones. In the spinal cord, the epileptiform activity displayed a different paroxysmal pattern, characterized by the longest duration and the highest amplitude. The different sensitivities of the investigated brain structures to penicillin-G and the characteristics of the induced paroxysmal activity have been extensively discussed.  相似文献   
40.
Glycogen storage disease type Ia (GSDIa) is an inherited metabolic disorder caused by mutations in the enzyme glucose-6-phosphatase-α (G6Pase-α). Affected individuals develop renal and liver complications, including the development of hepatocellular adenoma/carcinoma and kidney failure. The purpose of this study was to identify potential biomarkers of the evolution of the disease in GSDIa patients. To this end, we analyzed the expression of exosomal microRNAs (Exo-miRs) in the plasma exosomes of 45 patients aged 6 to 63 years. Plasma from age-matched normal individuals were used as controls. We found that the altered expression of several Exo-miRs correlates with the pathologic state of the patients and might help to monitor the progression of the disease and the development of late GSDIa-associated complications.  相似文献   
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