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141.
Auber Andor Nyikó Tünde Mérai Zsuzsanna Silhavy Dániel 《Plant Molecular Biology Reporter》2018,36(5-6):858-869
Plant Molecular Biology Reporter - Eukaryotic translation termination is mediated by two conserved interacting release factors, eRF1 and eRF3. eRF1 recognizes the stop codon and promotes the... 相似文献
142.
Zusammenfassung Die Zahl der mit einem alkylierenden Agens (Zitostop) in vitro induzierten Mutationen zeigt individuelle Schwankungen.Beim Down-Syndrom, dessen häufige Kombination mit malignen Erkrakungen bekannt ist, und bei 2 Mitgliedern einer Krebsfamilie wird eine statistisch signifikant erhöhte Zahl von induzierten Mutationen gegenüber Gesunden festgestellt.Bei der Ataxia teleangiektasia und bei akuter lymphoblastischer Leukämie im Remissionsstadium sind nur in einigen Fällen Chromosomenaberrationen in vitro gegenüber Normalen induzierbar. Nach unseren Beobachtungen stellt sich die Frage, ob die mit alkylierenden Agentien in vitro durchgeführten Untersuchungen zum Nachweis gesteigerten Mutationsneigung geeignet sind.
Mutations induced in vitro by an alkylating agent (Zitostop) in malignant diseases and syndromes predisposing to malignancy
Summary According to our observations the number of chromosome mutations induced in vitro by an alkylating agent (Zitostop) shows individual variations. In Down's syndrome, which is accompanied by a higher incidence of malignancy, and in two members of a cancer family the number of mutations induced was significantly higher than in controls. In ataxia telangiectasia and in the complete remission phase of acute lymphoid leukaemia the number of mutations induced was higher only in some cases. The question of whether recording the number of chromosome mutations induced by an alkylating agent is a suitable procedure for the detection of an increased mutability or not is left open.相似文献
143.
Adam M. Nagy Rebeka Fekete Gergo Horvath Gabor Koncsos Csilla Kriston Anna Sebestyen Zoltan Giricz Zsuzsanna Kornyei Emilia Madarasz Laszlo Tretter 《BBA》2018,1859(3):201-214
Microglia are highly dynamic cells in the brain. Their functional diversity and phenotypic versatility brought microglial energy metabolism into the focus of research. Although it is known that microenvironmental cues shape microglial phenotype, their bioenergetic response to local nutrient availability remains unclear.In the present study effects of energy substrates on the oxidative and glycolytic metabolism of primary – and BV-2 microglial cells were investigated. Cellular oxygen consumption, glycolytic activity, the levels of intracellular ATP/ADP, autophagy, mTOR phosphorylation, apoptosis and cell viability were measured in the absence of nutrients or in the presence of physiological energy substrates: glutamine, glucose, lactate, pyruvate or ketone bodies.All of the oxidative energy metabolites increased the rate of basal and maximal respiration. However, the addition of glucose decreased microglial oxidative metabolism and glycolytic activity was enhanced. Increased ATP/ADP ratio and cell viability, activation of the mTOR and reduction of autophagic activity were observed in glutamine-supplemented media. Moreover, moderate and transient oxidation of ketone bodies was highly enhanced by glutamine, suggesting that anaplerosis of the TCA-cycle could stimulate ketone body oxidation.It is concluded that microglia show high metabolic plasticity and utilize a wide range of substrates. Among them glutamine is the most efficient metabolite. To our knowledge these data provide the first account of microglial direct metabolic response to nutrients under short-term starvation and demonstrate that microglia exhibit versatile metabolic machinery. Our finding that microglia have a distinct bioenergetic profile provides a critical foundation for specifying microglial contributions to brain energy metabolism. 相似文献
144.
Wiebke Garrels Ayan Mukherjee Stephanie Holler Nicole Cleve Thirumala R. Talluri Brigitte Barg-Kues Mike Diederich Peter Köhler Björn Petersen Andrea Lucas-Hahn Heiner Niemann Zsuzsanna Izsvák Zoltán Ivics Wilfried A. Kues 《Transgenic research》2016,25(1):63-70
Recently, we established the Sleeping Beauty transposon system for germ line competent transgenesis in the pig. Here, we extend this approach to re-target a transposon-tagged locus for a site-specific gene knock-in, and generated a syngeneic cohort of piglets carrying either the original transposon or the re-targeted event. A Cre-loxP-mediated cassette exchange of the tagging transposon with a different reporter gene was performed, followed by flow cytometric sorting and somatic cell nuclear transfer of recombined cells. In parallel, the original cells were employed in somatic cell nuclear transfer to generate clone siblings, thereby resulting in a clone cohort of piglets carrying different reporter transposons at an identical chromosomal location. Importantly, this strategy supersedes the need for an antibiotic selection marker. This approach expands the arsenal of genome engineering technologies in domestic animals, and will facilitate the development of large animal models for human diseases. Potentially, the syngeneic cohort of pigs will be instrumental for vital tracking of transplanted cells in pre-clinical assessments of novel cell therapies. 相似文献
145.
146.
In the last decades, several expeditions were organized in Europe by the researchers of the Hungarian Natural History Museum to collect snails, aquatic insects and soil animals (mites, springtails, nematodes, and earthworms). In this study, scale insect (Hemiptera: Coccomorpha) specimens extracted from Hungarian Natural History Museum soil samples (2970 samples in total), all of which were collected using soil and litter sampling devices, and extracted by Berlese funnel, were examined. From these samples, 43 scale insect species (Acanthococcidae 4, Coccidae 2, Micrococcidae 1, Ortheziidae 7, Pseudococcidae 21, Putoidae 1 and Rhizoecidae 7) were found in 16 European countries. In addition, a new species belonging to the family Pseudococcidae, Brevennia
larvalis Kaydan, sp. n. and a new species of Ortheziidae, Ortheziola
editae Szita & Konczné Benedicty, sp. n. are described and illustrated based on the adult female stage. Revised keys to the adult females of Brevennia and Ortheziola are presented. 相似文献
147.
Kargul J Maghlaoui K Murray JW Deak Z Boussac A Rutherford AW Vass I Barber J 《Biochimica et biophysica acta》2007,1767(6):404-413
The core complex of photosystem II (PSII) was purified from thermophilic cyanobacterium Thermosynechococcus elongatus grown in Sr(2+)-containing and Ca(2+)-free medium. Functional in vivo incorporation of Sr(2+) into the oxygen-evolving complex (OEC) was confirmed by EPR analysis of the isolated and highly purified SrPSII complex in agreement with the previous study of Boussac et al. [J. Biol. Chem. 279 (2004) 22809-22819]. Three-dimensional crystals of SrPSII complex were obtained which diffracted to 3.9 A and belonged to the orthorhombic space group P2(1)2(1)2(1) with unit cell dimensions of a=133.6 A, b=236.6 A, c=307.8 A. Anomalous diffraction data collected at the Sr K-X-ray absorption edge identified a novel Sr(2+)-binding site which, within the resolution of these data (6.5 A), is consistent with the positioning of Ca(2+) in the recent crystallographic models of PSII [Ferreira et al. Science 303 (2004) 1831-1838, Loll et al. Nature 438 (2005) 1040-1044]. Fluorescence measurements on SrPSII crystals confirmed that crystallized SrPSII was active in transferring electrons from the OEC to the acceptor site of the reaction centre. However, SrPSII showed altered functional properties of its modified OEC in comparison with that of the CaPSII counterpart: slowdown of the Q(A)-to-Q(B) electron transfer and stabilized S(2)Q(A)(-) charge recombination. 相似文献
148.
The water-oxidizing complex of Photosystem II is an important target of ultraviolet-B (280-320 nm) radiation, but the mechanistic background of the UV-B induced damage is not well understood. Here we studied the UV-B sensitivity of Photosystem II in different oxidation states, called S-states of the water-oxidizing complex. Photosystem II centers of isolated spinach thylakoids were synchronized to different distributions of the S(0), S(1), S(2) and S(3) states by using packages of visible light flashes and were exposed to UV-B flashes from an excimer laser (lambda=308 nm). The loss of oxygen evolving activity showed that the extent of UV-B damage is S-state-dependent. Analysis of the data obtained from different synchronizing flash protocols indicated that the UV-sensitivity of Photosystem II is significantly higher in the S(3) and S(2) states than in the S(1) and S(0) states. The data are discussed in terms of a model where UV-B-induced inhibition of water oxidation is caused either by direct absorption within the catalytic manganese cluster or by damaging intermediates of the water oxidation process. 相似文献
149.
Short Inverted-Repeat Transposable Elements in Teleost Fish and Implications for a Mechanism of Their Amplification 总被引:7,自引:0,他引:7
Zsuzsanna Izsvák Zoltán Ivics Nobuyoshi Shimoda Deanna Mohn Hitoshi Okamoto Perry B. Hackett 《Journal of molecular evolution》1999,48(1):13-21
Angel is the first miniature inverted-repeat transposable element (MITE) isolated from fish. Angel elements are imperfect palindromes with the potential to form stem-loop structures in vitro. Despite sequence divergence
of elements of up to 55% within and between species, their inverted repeat structures have been maintained, implying functional
importance. We estimate that there are about 103–104
Angels scattered throughout the zebrafish genome, evidence that this family of transposable elements has been significantly amplified
over the course of evolution. Angel elements and Xenopus MITEs carry common sequence motifs at their termini, indicating common origin and/or related mechanisms of transposition.
We present a model in which MITEs take advantage of the basic cellular mechanism of DNA replication for their amplification,
which is dependent on the characteristic inverted repeat structures of these elements. We propose that MITEs are genomic parasites
that transpose via a DNA intermediate, which forms by a folding-back of a single strand of DNA, that borrow all of the necessary
factors for their amplification from products encoded in the genomes in which they reside. DNA polymorphisms in different
lines of zebrafish were detected by PCR using Angel-specific primers, indicating that such elements, combined with other transposons in vertebrate genomes, will be useful molecular
tools for genome mapping and genetic analyses of mutations.
Received: 7 April 1998 / Accepted: 7 April 1998 相似文献
150.