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11.
Jan Traub Katja Grondey Tobias Gassenmaier Dominik Schmitt Georg Fette Stefan Frantz Valrie Boivin-Jahns Roland Jahns Stefan Strk Guido Stoll Theresa Reiter Ulrich Hofmann Martin S. Weber Anna Frey 《International journal of molecular sciences》2022,23(18)
Acute ischemic cardiac injury predisposes one to cognitive impairment, dementia, and depression. Pathophysiologically, recent positron emission tomography data suggest astroglial activation after experimental myocardial infarction (MI). We analyzed peripheral surrogate markers of glial (and neuronal) damage serially within 12 months after the first ST-elevation MI (STEMI). Serum levels of glial fibrillary acidic protein (GFAP) and neurofilament light chain (NfL) were quantified using ultra-sensitive molecular immunoassays. Sufficient biomaterial was available from 45 STEMI patients (aged 28 to 78 years, median 56 years, 11% female). The median (quartiles) of GFAP was 63.8 (47.0, 89.9) pg/mL and of NfL 10.6 (7.2, 14.8) pg/mL at study entry 0–4 days after STEMI. GFAP after STEMI increased in the first 3 months, with a median change of +7.8 (0.4, 19.4) pg/mL (p = 0.007). It remained elevated without further relevant increases after 6 months (+11.7 (0.6, 23.5) pg/mL; p = 0.015), and 12 months (+10.3 (1.5, 22.7) pg/mL; p = 0.010) compared to the baseline. Larger relative infarction size was associated with a higher increase in GFAP (ρ = 0.41; p = 0.009). In contrast, NfL remained unaltered in the course of one year. Our findings support the idea of central nervous system involvement after MI, with GFAP as a potential peripheral biomarker of chronic glial damage as one pathophysiologic pathway. 相似文献
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More than forty years after the first birth following in vitro fertilization (IVF), the success rates of IVF and of IVF-derived assisted reproduction techniques (ART) still remain relatively low. Interindividual differences between infertile couples and the nature of the problems underlying their infertility appear to be underestimated nowadays. Consequently, the molecular basis of each couple’s reproductive function and of its disturbances is needed to offer an individualized diagnostic and therapeutic approaches to each couple, instead of applying a standard or minimally adapted protocols to everybody. Interindividual differences include sperm and oocyte function and health status, early (preimplantation) embryonic development, the optimal window of uterine receptivity for the implanting embryo, the function of the corpus luteum as the main source of progesterone production during the first days of pregnancy, the timing of the subsequent luteoplacental shift in progesterone production, and aberrant reactions of the uterine immune cells to the implanting and recently implanted embryos. In this article, the molecular basis that underlies each of these abnormalities is reviewed and discussed, with the aim to design specific treatment options to be used for each of them. 相似文献
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Four grades of alunite ore were mixed with four grades of fire clays, and the mixtures were formed into modulus of rupture test bars. These were fired to cone 13–14. Specimens were tested for bulk density and modulus of rupture after the initial firing and after reheating to 1400°C. and 1600°C. Softening temperatures of the mixtures were also determined. In general, small quantities (not exceeding 20%) of alunites improved fired characteristics, including decreasing the reheat shrinkage and increasing the P.C.E. The purity of both raw materials was the determining factor. Excessive additions of alunite, particularly to the low-grade clays, caused bloating as a result of the evolution of sulfur gases from the alunite. 相似文献
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Investigation of the morphology and properties of ternary composites of polypropylene, ethylene-propylene-diene terpolymer, and filler has shown that in such systems two kinds of structures can be formed: separate dispersion of the components or encapsulation of the filler by the elastomer. A thermodynamic analysis of the two structures revealed that encapsulation is the thermodynamically favored process. The final structure is determined by the stability of the encapsulated units, which depends on the relative magnitude of adhesion and shear forces. The former depends on the reversible work of adhesion and on the particle size of the filler, while the latter depends on the viscosity and shear rate. Surface treatment of the filler decreases the work of adhesion, resulting in extensive de-encapsulation. The developed tentative explanation is in agreement with the observed phenomena and experimental results. 相似文献
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Hanne Hjorth Te?nnesen Jan Karlsen Anne -Lise Grislingaas Korattiyil Velayudhan Nair Balakrishnan Payyeri Ayyappan James Verghese 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1992,194(6):570-572
Summary Three varieties ofCurcuma longa andC. aromatica were investigated during a growth period of 17 weeks with respect to the content of curcuminoids in the bulbs and fingers. A decrease in pigment production as a function of maturity of the rhizomes was observed. The total content of curcuminoids was equal inC. longa andC. aromatica, but with a slight difference in distribution between the fingers and bulbs in the two species. Taking the biomass into account, the fingers will be more beneficial for the isolation of curcuminoids than the respective bulbs.
Studien über Curcumin und Curcuminoide XXI. Unterschiede des Gehaltes an Curcuminoiden bei Curcuma longa L. und Curcuma aromatica Salisb. aus Indien während einer Saison
Zusammenfassung Drei Typen vonCurcuma longa undC. aromatica wurden während einer Wachstumsperiode von 17 Wochen auf ihren Curcuminoidgehalt in den Knollen und im Wurzelstock untersucht. Eine Abnahme der Pigmentproduktion in Abhängigkeit von dem Entwicklungsstadium der Rhizome wurde festgestellt. Der Gesamtgehalt an Curcuminoiden beiC. longa undC. aromatica war der gleiche, doch bestand ein geringer Unterschied in der Verteilung dieser zwischen Knolle und Wurzelstock bei den beiden Spezies. Bei Betrachtung der Biomasse ist der Wurzelstock für die Isolation von Curcuminoiden besser geeignet als die Knollen.相似文献
17.
Jingjin Dong Jian Liu Xinkai Qiu Ryan Chiechi L.Jan Anton Koster Giuseppe Portale 《工程(英文)》2021,7(5):647-654
Engineering the electrical properties of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)(PEDOT:PSS)holds great potential for various applications such a... 相似文献
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Stegenga J Le Feber J Marani E Rutten WL 《IEEE transactions on bio-medical engineering》2008,55(4):1382-1390
It is an open question whether neuronal networks, cultured on multielectrode arrays, retain any capability to usefully process information (learning and memory). A necessary prerequisite for learning is that stimulation can induce lasting changes in the network. To observe these changes, one needs a method to describe the network in sufficient detail, while stable in normal circumstances. We analyzed the spontaneous bursting activity that is encountered in dissociated cultures of rat neocortical cells. Burst profiles (BPs) were made by estimating the instantaneous array-wide firing frequency. The shape of the BPs was found to be stable on a time scale of hours. Spatiotemporal detail is provided by analyzing the instantaneous firing frequency per electrode. The resulting phase profiles (PPs) were estimated by aligning BPs to their peak spiking rate over a period of 15 min. The PPs reveal a stable spatiotemporal pattern of activity during bursts over a period of several hours, making them useful for plasticity and learning studies. We also show that PPs can be used to estimate conditional firing probabilities. Doing so, yields an approach in which network bursting behavior and functional connectivity can be studied. 相似文献