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931.
Jeffrey K. Mito Richard F. Riedel Leslie Dodd Guy Lahat Alexander J. Lazar Rebecca D. Dodd Lars Stangenberg William C. Eward Francis J. Hornicek Sam S. Yoon Brian E. Brigman Tyler Jacks Dina Lev Sayan Mukherjee David G. Kirsch 《PloS one》2009,4(11)
Undifferentiated pleomorphic sarcoma/Malignant Fibrous Histiocytoma (MFH) is one of the most common subtypes of human soft tissue sarcoma. Using cross species genomic analysis, we define a geneset from the LSL-KrasG12D; Trp53Flox/Flox mouse model of soft tissue sarcoma that is highly enriched in human MFH. With this mouse geneset as a filter, we identify expression of the RAS target FOXM1 in human MFH. Expression of Foxm1 is elevated in mouse sarcomas that metastasize to the lung and tissue microarray analysis of human MFH correlates overexpression of FOXM1 with metastasis. These results suggest that genomic alterations present in human MFH are conserved in the LSL-KrasG12D; p53Flox/Flox mouse model of soft tissue sarcoma and demonstrate the utility of this pre-clinical model. 相似文献
932.
Tobias Karlberg Susanne van den Berg Martin Hammarstr?m Johanna Sagemark Ida Johansson Lovisa Holmberg-Schiavone Herwig Schüler 《PloS one》2009,4(10)
Paraplegin is an m-AAA protease of the mitochondrial inner membrane that is linked to hereditary spastic paraplegias. The gene encodes an FtsH-homology protease domain in tandem with an AAA+ homology ATPase domain. The protein is believed to form a hexamer that uses ATPase-driven conformational changes in its AAA-domain to deliver substrate peptides to its protease domain. We present the crystal structure of the AAA-domain of human paraplegin bound to ADP at 2.2 Å. This enables assignment of the roles of specific side chains within the catalytic cycle, and provides the structural basis for understanding the mechanism of disease mutations.
Enhanced version
This article can also be viewed as an enhanced version in which the text of the article is integrated with interactive 3D representations and animated transitions. Please note that a web plugin is required to access this enhanced functionality. Instructions for the installation and use of the web plugin are available in Text S1. 相似文献933.
Activated carbon (AC) is widely used in ecological studies to elucidate the role of allelopathic substances in interspecific
plant competition. However, by adsorbing chemical signalling compounds AC may also have negative effects on plants with symbiosis
partners such as arbuscular mycorrhizal fungi and rhizobia. Here we test whether addition of AC has detrimental effects on
the mycorrhizal root colonization of the native forb Plantago lanceolata and the exotic legume Lupinus polyphyllus, the nodulation of L. polyphyllus, and the nutrient uptake and growth of the plants growing in intra- and interspecific competition. Allelopathic effects probably
occurred in the germination and seedling establishment phase when P. lanceolata suffered from the presence of L. polyphyllus. However, this negative effect of L. polyphyllus on P. lanceolata was not ameliorated by AC addition. AC negatively affected L. polyphyllus root biomass in week 4, and root and shoot biomass of P. lanceolata in week 9 of the experiment; both effects were independent of the presence and absence of the competing plant species. Mycorrhizal
root colonization of both plant species was reduced in the presence of AC, although the effect tended to be stronger for L. polyphyllus. No significant effect of AC on the nodulation of L. polyphyllus was detected. P. lanceolata was the superior competitor and led to reduced biomasses of L. polyphyllus in interspecific competition. We conclude that AC can reduce the mycorrhization and performance of plants which may lead
to changes in interspecific competition without the involvement of allelopathy. Contrary to former studies the AC used in
our study did not enhance the nutrient availability for the plants, but reduced plant growth and mycorrhization. We suggest
that the nutrient properties of the used AC are of crucial importance for the direction and the mechanisms of the effects
and should always be reported. 相似文献
934.
Melanie Zaparty Dominik Esser Susanne Gertig Patrick Haferkamp Theresa Kouril Andrea Manica Trong K. Pham Julia Reimann Kerstin Schreiber Pawel Sierocinski Daniela Teichmann Marleen van Wolferen Mathias von Jan Patricia Wieloch Sonja V. Albers Arnold J. M. Driessen Hans-Peter Klenk Christa Schleper Dietmar Schomburg John van der Oost Phillip C. Wright Bettina Siebers 《Extremophiles : life under extreme conditions》2010,14(1):119-142
935.
936.
Paulette Conget Fernando Rodriguez Susanne Kramer Carolina Allers Valeska Simon Francis Palisson Sergio Gonzalez Maria J. Yubero 《Cytotherapy》2010,12(3):429-431
In animal models it has been shown that mesenchymal stromal cells (MSC) contribute to skin regeneration and accelerate wound healing. We evaluated whether allogeneic MSC administration resulted in an improvement in the skin of two patients with recessive dystrophic epidermolysis bullosa (RDEB; OMIM 226600). Patients had absent type VII collagen immunohistofluorescence and since birth had suffered severe blistering and wounds that heal with scarring. Vehicle or 0.5 × 106 MSC were infused intradermally in intact and chronic ulcerated sites. One week after intervention, in MSC-treated skin type VII collagen was detected along the basement membrane zone and the dermal–epidermal junction was continuous. Re-epithelialization of chronic ulcerated skin was observed only near MSC administration sites. In both patients the observed clinical benefit lasted for 4 months. Thus intradermal administration of allogeneic MSC associates with type VII collagen replenishment at the dermal–epidermal junction, prevents blistering and improves wound healing in unconditioned patients with RDEB. 相似文献
937.
938.
Jorn R De Haan Ester Piek Rene C van Schaik Jacob de Vlieg Susanne Bauerschmidt Lutgarde MC Buydens Ron Wehrens 《BMC bioinformatics》2010,11(1):158
Background
Gene expression data can be analyzed by summarizing groups of individual gene expression profiles based on GO annotation information. The mean expression profile per group can then be used to identify interesting GO categories in relation to the experimental settings. However, the expression profiles present in GO classes are often heterogeneous, i.e., there are several different expression profiles within one class. As a result, important experimental findings can be obscured because the summarizing profile does not seem to be of interest. We propose to tackle this problem by finding homogeneous subclasses within GO categories: preclustering. 相似文献939.
The case for Survivin as mitotic regulator 总被引:13,自引:0,他引:13
Survivin has been proposed to inhibit apoptosis and to regulate cell division. However, controversy still exists as to whether Survivin can indeed execute these distinct functions and if Survivin somehow coordinates apoptosis and (abnormal) cell division. Recent evidence has demonstrated that Survivin acts as a subunit of the chromosomal passenger complex, which is essential for proper chromosome segregation and cytokinesis. Within this complex, the mitotic kinase Aurora B acts as the enzymatic core, whereas Survivin dictates chromosomal passenger complex localization. This function of Survivin appears to be conserved throughout evolution. Although these findings do not exclude a role for Survivin as apoptosis inhibitor, they make a very strong case for Survivin as mitotic regulator. 相似文献
940.
Wållberg A Nilsson K Osterlund K Peterson A Elg S Raboisson P Bauer U Hammerland LG Mattsson JP 《Bioorganic & medicinal chemistry letters》2006,16(5):1142-1145
Fenobam (1) was developed by McNeil Laboratories as an anxiolytic agent with an unknown molecular target in the late 1970s. In a recent publication, it was revealed that fenobam is a non-competitive mGluR5 antagonist. Herein, we present the structure-activity relationship of fenobam and its analogues and similarities between the SAR of mGluR5 antagonism and the SAR of CNS properties originally reported by McNeil are discussed. 相似文献