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81.
82.
Joseph E. Spraker Kelsea Jewell Ludmila V. Roze Jacob Scherf Dora Ndagano Randolph Beaudry John E. Linz Caitilyn Allen Nancy P. Keller 《Journal of chemical ecology》2014,40(5):502-513
Microbes in the rhizosphere have a suite of extracellular compounds, both primary and secondary, that communicate with other organisms in their immediate environment. Here, we describe a two-way volatile interaction between two widespread and economically important soil-borne pathogens of peanut, Aspergillus flavus and Ralstonia solanacearum, a fungus and bacterium, respectively. In response to A. flavus volatiles, R. solanacearum reduced production of the major virulence factor extracellular polysaccharide (EPS). In parallel, A. flavus responded to R. solanacearum volatiles by reducing conidia production, both on plates and on peanut seeds and by increasing aflatoxin production on peanut. Volatile profiling of these organisms using solid-phase micro-extraction gas chromatography mass spectroscopy (SPME-GCMS) provided a first glimpse at the compounds that may drive these interactions. 相似文献
83.
Natalya Kudryavtseva Aleksey Ermolaev Gennady Karlov Ilya Kirov Masayoshi Shigyo Shusei Sato Ludmila Khrustaleva 《International journal of molecular sciences》2021,22(11)
In situ imaging of molecular markers on a physical chromosome is an indispensable tool for refining genetic maps and validation genome assembly at the chromosomal level. Despite the tremendous progress in genome sequencing, the plant genome assembly at the chromosome level remains a challenge. Recently developed optical and Hi-C mapping are aimed at assistance in genome assembly. For high confidence in the genome assembly at chromosome level, more independent approaches are required. The present study is aimed at refining an ultrasensitive Tyr-FISH technique and developing a reliable and simple method of in situ mapping of a short unique DNA sequences on plant chromosomes. We have carefully analyzed the critical steps of the Tyr-FISH to find out the reasons behind the flaws of this technique. The accurate visualization of markers/genes appeared to be significantly dependent on the means of chromosome slide preparation, probe design and labeling, and high stringency washing. Appropriate adjustment of these steps allowed us to detect a short DNA sequence of 1.6 Kb with a frequency of 51.6%. Based on our results, we developed a more reliable and simple protocol for dual-color Tyr-FISH visualization of unique short DNA sequences on plant chromosomes. This new protocol can allow for more accurate determination of the physical distance between markers and can be applied for faster integration of genetic and cytogenetic maps. 相似文献
84.
Galina Vladimirovna Kontsevaya Ludmila Alekseevna Gerlinskaya Yury Mikhailovich Moshkin Margarita Vladimirovna Anisimova Aliya Konstantinovna Stanova Tatyana Ivanovna Babochkina Mikhail Pavlovich Moshkin 《International journal of molecular sciences》2021,22(19)
The latest vaccination campaign has actualized the potential impact of antigenic stimuli on reproductive functions. To address this, we mimicked vaccination’s effects by administering keyhole limpet hemocyanin (KLH ) to CD1 male mice and used their sperm for in vitro fertilization (IVF). Two-cell embryos after IVF with spermatozoa from control (C) or KLH-treated (Im) male mice were transferred to surrogate mothers mated with vasectomized control (C) or KLH-treated (Im) male mice, resulting in four experimental groups: C–C, Im–C, C–Im, and Im–Im. The pre-implantation losses were significantly lower in the Im–C group than in the C–Im group. At the same time, the resorption rates reduced markedly in the C–Im compared to the Im–C group. Embryo and placenta weights were significantly higher in the Im–Im group. Although the GM-CSF levels were lower in the amniotic fluid of the gestating surrogate mothers in the Im–Im group, they were strongly correlated with embryo mass. The number–size trade-off was only significant in the Im–Im group. This suggests a positive, cooperative effect of spermatozoa and seminal fluid from immune-primed males on embryo growth and the optimal distribution of surrogate mother maternal resources despite the negative impact of males’ antigenic challenge on the IVF success rate. 相似文献
85.
Anastasia V. Poznyak Evgeny E. Bezsonov Ali H. Eid Tatyana V. Popkova Ludmila V. Nedosugova Antonina V. Starodubova Alexander N. Orekhov 《International journal of molecular sciences》2021,22(9)
COVID-19 is a highly contagious new infection caused by the single-stranded RNA Sars-CoV-2 virus. For the first time, this infection was recorded in December 2019 in the Chinese province of Wuhan. The virus presumably crossed the interspecies barrier and passed to humans from a bat. Initially, the disease was considered exclusively in the context of damage to the respiratory system, but it quickly became clear that the disease also entails serious consequences from various systems, including the cardiovascular system. Among these consequences are myocarditis, myocardial damage, subsequent heart failure, myocardial infarction, and Takotsubo syndrome. On the other hand, clinical data indicate that the presence of chronic diseases in a patient aggravates the course and outcome of coronavirus infection. In this context, the relationship between COVID-19 and atherosclerosis, a condition preceding cardiovascular disease and other disorders of the heart and blood vessels, is particularly interesting. The renin-angiotensin system is essential for the pathogenesis of both coronavirus disease and atherosclerosis. In particular, it has been shown that ACE2, an angiotensin-converting enzyme 2, plays a key role in Sars-CoV-2 infection due to its receptor activity. It is noteworthy that this enzyme is important for the normal functioning of the cardiovascular system. Disruptions in its production and functioning can lead to various disorders, including atherosclerosis. 相似文献
86.
We compare eleven methods for finding prototypes upon which to base the nearest prototype classifier. Four methods for prototype selection are discussed: Wilson+Hart (a condensation+error‐editing method), and three types of combinatorial search—random search, genetic algorithm, and tabu search. Seven methods for prototype extraction are discussed: unsupervised vector quantization, supervised learning vector quantization (with and without training counters), decision surface mapping, a fuzzy version of vector quantization, c‐means clustering, and bootstrap editing. These eleven methods can be usefully divided two other ways: by whether they employ pre‐ or postsupervision; and by whether the number of prototypes found is user‐defined or “automatic.” Generalization error rates of the 11 methods are estimated on two synthetic and two real data sets. Offering the usual disclaimer that these are just a limited set of experiments, we feel confident in asserting that presupervised, extraction methods offer a better chance for success to the casual user than postsupervised, selection schemes. Finally, our calculations do not suggest that methods which find the “best” number of prototypes “automatically” are superior to methods for which the user simply specifies the number of prototypes. © 2001 John Wiley & Sons, Inc. 相似文献
87.
Jana Hajlová Jii Davidek Ludmila Fierová und Jan Veliek 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1984,178(5):382-385
Zusammenfassung In Äpfeln, welche mit den Pesticiden Melprex 65 W und/oder Anthio 25 behandelt wurden, und weiterhin in nicht behandelten Früchten (Kontrolle) wurden bedeutende Mengen von Substraten der Polyphenoloxidasen festgestellt. In den Proben wurden unterschiedliche Mengen von o-Diphenolen und phenolischen Säuren gefunden. Eine signifikant niedrigere Menge dieser Stoffe wurde in den mit Melprex 65 W behandelten Früchten nachgewiesen. Die Aktivität der Polyphenoloxidasen in dieser Probe ist fast identisch mit der Kontrolle. In den mit Anthio 25 behandelten Früchten beobachtete man ein etwas geringeres Braunwerden. Interessant ist die Feststellung, daß Dodine, der aktive Bestandteil von Melprex 65 W, die Bildung von Farbprodukten bei den Reaktionen der enzymatischen Bräunung beeinflußt.
The influence of some pesticides on the quality of apples. I. Enzymatic browning reactions
Summary The contents of some significant substrates of apple polyphenol oxidase were determined either in fruit treated with Melprex 65 W and/or Anthio 25 and in untreated fruit. Some differences were found in the concentrations of o-Dihydroxyphenols and phenolic acids. The significantly lower content of these substances was checked in apples treated with Melprex 65 W. The activity of polyphenol oxidase in this sample was nearly the same as that in a control. A slightly lower rate of browning was observed in apples treated with Anthio 25. It was proved that dodine (active ingredient of Melprex 65 W) participates in the formation of coloured products originating during enzymatic browning reactions.相似文献
88.
Rainer Mahrwald Hans Schick Ludmila L. Vasil'eva Kasimir K. Pivnitsky Gisela Weber Sigfrid Schwarz 《Advanced Synthesis \u0026amp; Catalysis》1990,332(2):169-175
Starting with the racemic aldehyde 4 , prepared from the tris(trimethylsilyl) ether 3 , the possibility was demonstrated of converting a trimethylsilylated primary hydroxy group with high selectivity into an aldehyde group in the presence of two trimethylsilylated secondary hydroxy groups employing oxalyl chloride and dimethyl sulfoxide (Swern reagent) as oxidant. The alkynylation of this aldehyde with 1-metalated hept-1-yne afforded a chromatographically separable mixture of two diastereomeric alcohols, both being suitable intermediates for the synthesis of PGF2α. The diastereofacial selectivity of the addition strongly depends on the metal employed. Hept-1-yn-1-yllithium afforded a 67:33 mixture of (13 R*)- and (13 S*)-alcohol, hept-1-yn-1-yltriisopropoxytitanium, however, a 30:70 mixture. 相似文献
89.
Jan ermk Ludmila Soukupov Vclav Chvalovský Elena M. Kharkova Boris A. Krentsel 《Advanced Synthesis \u0026amp; Catalysis》1991,333(2):249-253
Sodium dihydridobis(2-methoxyethoxo)aluminate (SDMA) is a suitable reducing agent for in situ generation of zerovalent nickel in a catalytic system nickel(II) 2, 4-pentanedionate/phosphorus(III) ligand/reducing agent. Although generally less polymer is formed in the propadiene/propyne cooligomerization catalyzed by this system when the reducing agent is triethylaluminium, at molar ratios Al/Ni = 3 and P/Ni = 3 no polymer is formed with SDMA and the yield of oligomers is comparable to that obtained with triethylaluminium. 相似文献
90.