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951.
Thomas Kubin Praveen Gajawada Peter Bramlage Stefan Hein Benedikt Berge Ayse Cetinkaya Heiko Burger Markus Schnburg Wolfgang Schaper Yeong-Hoon Choi Manfred Richter 《International journal of molecular sciences》2022,23(3)
Oncostatin M (OSM), a member of the interleukin-6 family, functions as a major mediator of cardiomyocyte remodeling under pathological conditions. Its involvement in a variety of human cardiac diseases such as aortic stenosis, myocardial infarction, myocarditis, cardiac sarcoidosis, and various cardiomyopathies make the OSM receptor (OSMR) signaling cascades a promising therapeutic target. However, the development of pharmacological treatment strategies is highly challenging for many reasons. In mouse models of heart disease, OSM elicits opposing effects via activation of the type II receptor complex (OSMR/gp130). Short-term activation of OSMR/gp130 protects the heart after acute injury, whereas chronic activation promotes the development of heart failure. Furthermore, OSM has the ability to integrate signals from unrelated receptors that enhance fetal remodeling (dedifferentiation) of adult cardiomyocytes. Because OSM strongly stimulates the production and secretion of extracellular proteins, it is likely to exert systemic effects, which in turn, could influence cardiac remodeling. Compared with the mouse, the complexity of OSM signaling is even greater in humans because this cytokine also activates the type I leukemia inhibitory factor receptor complex (LIFR/gp130). In this article, we provide an overview of OSM-induced cardiomyocyte remodeling and discuss the consequences of OSMR/gp130 and LIFR/gp130 activation under acute and chronic conditions. 相似文献
952.
Ya-Fei Zhao Wen-Jing Ren Ying Zhang Jin-Rong He Hai-Yan Yin Yang Liao Patrizia Rubini Jan M. Deussing Alexei Verkhratsky Zeng-Qiang Yuan Peter Illes Yong Tang 《International journal of molecular sciences》2022,23(3)
Extracellular adenosine 5′-triphosphate (ATP) in the brain is suggested to be an etiological factor of major depressive disorder (MDD). It has been assumed that stress-released ATP stimulates P2X7 receptors (Rs) at the microglia, thereby causing neuroinflammation; however, other central nervous system (CNS) cell types such as astrocytes also possess P2X7Rs. In order to elucidate the possible involvement of the MDD-relevant hippocampal astrocytes in the development of a depressive-like state, we used various behavioral tests (tail suspension test [TST], forced swim test [FST], restraint stress, inescapable foot shock, unpredictable chronic mild stress [UCMS]), as well as fluorescence immunohistochemistry, and patch-clamp electrophysiology in wild-type (WT) and genetically manipulated rodents. The TST and FST resulted in learned helplessness manifested as a prolongation of the immobility time, while inescapable foot shock caused lower sucrose consumption as a sign of anhedonia. We confirmed the participation of P2X7Rs in the development of the depressive-like behaviors in all forms of acute (TST, FST, foot shock) and chronic stress (UCMS) in the rodent models used. Further, pharmacological agonists and antagonists acted in a different manner in rats and mice due to their diverse potencies at the respective receptor orthologs. In hippocampal slices of mice and rats, only foot shock increased the current responses to locally applied dibenzoyl-ATP (Bz-ATP) in CA1 astrocytes; in contrast, TST and restraint depressed these responses. Following stressful stimuli, immunohistochemistry demonstrated an increased co-localization of P2X7Rs with a microglial marker, but no change in co-localization with an astroglial marker. Pharmacological damage to the microglia and astroglia has proven the significance of the microglia for mediating all types of depression-like behavioral reactions, while the astroglia participated only in reactions induced by strong stressors, such as foot shock. Because, in addition to acute stressors, their chronic counterparts induce a depressive-like state in rodents via P2X7R activation, we suggest that our data may have relevance for the etiology of MDD in humans. 相似文献
953.
Frederick Wieland Lawrence Hawley Abe Feinberg Mike Di Loreto Leo Blume Joseph Ruffles Peter Reiher Brian Beckman Philip Hontalas Steven Bellenot David Jefferson 《Concurrency and Computation》1989,1(1):35-50
This paper analyzes the performance of a discrete-event combat simulation executed on a parallel processor under control of the Time Warp Operating System. Time Warp is in a class of distributed simulation methods called Optimistic methods which have proven to be useful over a wide range of simulations. The combat simulation used for this performance study, called STB88, is a division-corps model incorporating a number of different types of computations. The speed-up for three versions of this model on the Caltech/JPL Mark III Hypercube and the BBN Butterfly parallel processors was measured relative to an efficient sequential execution of the same model on the same hardware. The results indicate that STB88 version 1 achieves a speed-up of 28.6 on 60 Mark III processors, while STB88 version 2 achieves a speed-up of 36.8 on 100 Butterfly processors. Version 3 of STB88 achieved a speed-up of 38.5 on 128 Mark III processors. The versions differed only in their interface to Time Warp. On the Butterfly, the sequential execution completed in 2 hours, while the 100 processor execution completed in 3.2 minutes. 相似文献
954.
Juan M. Escamilla Molgora Luigi Sedda Peter J. Diggle Peter M. Atkinson 《Journal of the Royal Society Interface》2022,19(187)
Species distribution models (SDMs) are an important class of model for mapping taxa spatially and are a key tool for tackling biodiversity loss. However, most common SDMs depend on presence–absence data and, despite the accumulation and exponential growth of biological occurrence data across the globe, the available data are predominantly presence-only (i.e. they lack real absences). Although presence-only SDMs do exist, they inevitably require assumptions about absences of the considered taxa and they are specified mostly for single species and, thus, do not exploit fully the information in related taxa. This greatly limits the utility of global biodiversity databases such as GBIF. Here, we present a Bayesian-based SDM for multiple species that operates directly on presence-only data by exploiting the joint distribution between the multiple ecological processes and, crucially, identifies the sampling effort per taxa which allows inference on absences. The model was applied to two case studies. One, focusing on taxonomically diverse taxa over central Mexico and another focusing on the monophyletic family Cactacea over continental Mexico. In both cases, the model was able to identify the ecological and sampling effort processes for each taxon using only the presence observations, environmental and anthropological data. 相似文献
955.
Shaibal Roy Premkumar Kamalanathan Peter Lehner Thomas Turek Muthanna Al-Dahhan 《加拿大化工杂志》2020,98(1):294-307
Monolith reactors are widely considered as an alternative to the conventional trickle bed reactor. For the commercial deployment of monolith reactors, comparative performance studies are required. Reliable comparative and performance studies require a detailed understanding of the effect of phase distribution/maldistribution on the performance studies. In this work, performance and comparative studies were carried out in a relatively large column that was 4.8 cm in diameter. Experiments were performed in the same conditions that were used in studies for which phase distribution data were available. Since the properties of the catalyst used were different in both the reactors, the apparent kinetics were studied to facilitate the comparison. The hydrogenation of alpha-methyl styrene (AMS) was used as a test reaction. From the performance studies, it was found that the effect of maldistribution on the performance was stronger than the catalyst availability. From the comparative studies, it was found that the monolith reactor with maldistributed flow conditions provides higher productivity than the trickle bed reactor. 相似文献
956.
Currently, wet-chemical and thermochemical processes in particular are being discussed for the future obligatory recovery of phosphorus from sewage sludge. The coupling of phosphorus recovery with incineration in stationary fluidized bed incinerators, the dominant mono-incineration technology, offers potential advantages in terms of aftertreatment costs and economic efficiency. Tests have shown that by adjusting the incineration conditions and adding additives, an ash could be produced that corresponds to the fertilizer ordinance (DüMV) and can, therefore, potentially be used as phosphorus recyclate. 相似文献
957.
Polyethylene terephthalate (PET) is one of the most common thermoplastic polymers and its durability has become a major environmental concern. The current public debate on plastic debris also triggered the revision of PET recycling technologies. This Research Article focuses on the chemical recycling of PET by means of methanolysis. The process degrades PET into two main reaction products, dimethyl terephthalate (DMT) and ethylene glycol (EG). Subsequent separation by distillation combined with crystallization removes critical impurities and non-PET components from co-polymers, providing monomers of high purity needed for re-polymerization purposes. 相似文献
958.
Wolfgang Habel Werner Haeusler Peter Sartori 《Advanced Synthesis \u0026amp; Catalysis》1995,337(1):589-592
Photochlorination and Metalorganic Following Reactions of a Cross-linked Poly(carbosilane) The synthesis of a perchlorinated cross-linked poly(carbosilane) of the general composition [(Cl2Si)1,5(SiCl) (CCl2)3]x ( II ) was achieved through the photochlorination of [(Cl2Si)1,5(SiCl)(CH2)3]x ( I ). The perchlorinated product was investigated by elemental analysis and spectroscopic methods. Furthermore the permethylated and perphenylated compounds [(Me2Si)1,5(SiMe)(CMe2)3]x ( III ) and [(Ph2Si)1,5(SiPh)(CPh2)3]x ( IV ) were synthesized by reactions with methyl- and phenyllithium. The products obtained were characterized by elemental analysis and 1H, 13C, 29Si NMR and IR spectroscopy. The number and weight averages Mn and Mw were determined by gel permeation chromatography. 相似文献
959.
960.
Peter Weyerstahl 《Advanced Synthesis \u0026amp; Catalysis》1994,336(2):95-109
In contrast to previous hypotheses that there are a few primary odors, recent results show the existence of an extremely large number of receptors each capable of recognizing a small number of odorants. Although in principle enantiomers have different odors, in many cases the size of the difference is small or even zero. Minor structural change often has a major effect on the odor perceived. Detailed results of structure-odor relationship have been obtained with several classes of odorants. Most investigated are the classes of fatty aldehydes, degraded carotenoids, sandalwood odorants, ambergris and musk compounds. Various rules and correlations have been established. Despite numerous excellent studies during the last 30 years the area of structure-odor relationship remains rather confusing. 相似文献