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71.
Mohammad Hossein Esnaashary Masoud Karfarma Hamid Reza Rezaie Alireza Khavandi Jafar Javadpour 《仿生工程学报(英文版)》2021,18(3):623-636
Mimicking compositional and constructional features of the extracellular matrix(ECM)is an effective parameter in improving the biological response of biomateria... 相似文献
72.
Ting Xiang Neik Kaveh Ghanbarnia Bndicte Ollivier Armin Scheben Anita SevernEllis Nicholas J. Larkan Parham Haddadi Dilantha W. G. Fernando Thierry Rouxel Jacqueline Batley Hossein M. Borhan MarieHlne Balesdent 《Molecular Plant Pathology》2022,23(5):733
Brassica napus (oilseed rape, canola) seedling resistance to Leptosphaeria maculans, the causal agent of blackleg (stem canker) disease, follows a gene‐for‐gene relationship. The avirulence genes AvrLmS and AvrLep2 were described to be perceived by the resistance genes RlmS and LepR2, respectively, present in B. napus ‘Surpass 400’. Here we report cloning of AvrLmS and AvrLep2 using two independent methods. AvrLmS was cloned using combined in vitro crossing between avirulent and virulent isolates with sequencing of DNA bulks from avirulent or virulent progeny (bulked segregant sequencing). AvrLep2 was cloned using a biparental cross of avirulent and virulent L. maculans isolates and a classical map‐based cloning approach. Taking these two approaches independently, we found that AvrLmS and AvrLep2 are the same gene. Complementation of virulent isolates with this gene confirmed its role in inducing resistance on Surpass 400, Topas‐LepR2, and an RlmS‐line. The gene, renamed AvrLmS‐Lep2, encodes a small cysteine‐rich protein of unknown function with an N‐terminal secretory signal peptide, which is a common feature of the majority of effectors from extracellular fungal plant pathogens. The AvrLmS‐Lep2/LepR2 interaction phenotype was found to vary from a typical hypersensitive response through intermediate resistance sometimes towards susceptibility, depending on the inoculation conditions. AvrLmS‐Lep2 was nevertheless sufficient to significantly slow the systemic growth of the pathogen and reduce the stem lesion size on plant genotypes with LepR2, indicating the potential efficiency of this resistance to control the disease in the field. 相似文献
73.
Dalby MJ Riehle MO Sutherland DS Agheli H Curtis AS 《European journal of cell biology》2004,83(4):159-169
The environment around a cell during in vitro culture is unlikely to mimic those in vivo. Preliminary experiments with nanotopography have shown that nanoscale features can strongly influence cell morphology, adhesion, proliferation and gene regulation, but the mechanisms mediating this cell response remain unclear. In this perspective article, we attempt to illustrate that a possible mechanism is direct transmittal of forces encountered by cells during spreading to the nucleus via the cytoskeleton. We further try to illustrate that this 'self-induced' mechanotransduction may alter gene expression by changing interphase chromosome positioning. Whilst the observations described here to show how we think nanotopography can be developed as a tool to look at mechanotransduction are preliminary, we feel they indicate that topography may give cell biologists a non-invasive tool with which to investigate in vitro cellular mechanisms. 相似文献
74.
Control of biogenic H(2)S production with nitrite and molybdate 总被引:2,自引:0,他引:2
Nemati M Mazutinec TJ Jenneman GE Voordouw G 《Journal of industrial microbiology & biotechnology》2001,26(6):350-355
The effects of the metabolic inhibitors, sodium nitrite and ammonium molybdate, on production of H2S by a pure culture of the sulfate-reducing bacterium (SRB) Desulfovibrio sp. strain Lac6 and a consortium of SRB, enriched from produced water of a Canadian oil field, were investigated. Addition
of 0.1 mM nitrite or 0.024 mM molybdate at the start of growth prevented the production of H2S by strain Lac6. With exponentially growing cultures, higher levels of inhibitors, 0.25 mM nitrite or 0.095 mM molybdate,
were required to suppress the production of H2S. Simultaneous addition of nitrite and molybdate had a synergistic effect: at time 0, 0.05 mM nitrite and 0.01 mM molybdate,
whereas during the exponential phase, 0.1 mM nitrite and 0.047 mM molybdate were sufficient to stop H2S production. With an exponentially growing consortium of SRB, enriched from produced water of the Coleville oil field, much
higher levels of inhibitors, 4 mM nitrite or 0.47 mM molybdate, were needed to stop the production of H2S. The addition of these inhibitors had no effect on the composition of the microbial community, as shown by reverse sample
genome probing. The results indicate that the efficiency of inhibitors in containment of SRB depends on the composition and
metabolic state of the microbial community. Journal of Industrial Microbiology & Biotechnology (2001) 26, 350–355.
Received 02 August 2000/ Accepted in revised form 17 April 2001 相似文献
75.
Hakimelahi GH Shia KS Pasdar M Hakimelahi S Khalafi-Nezhad A Soltani MN Mei NW Mei HC Saboury AA Rezaei-Tavirani M Moosavi-Movahedi AA 《Bioorganic & medicinal chemistry》2002,10(9):2927-2932
A novel cephalosporin derivative of monohydroguaiaretic acid (cephem-M(3)N, 7) was synthesized and found to possess anticancer activity against human leukemia (K562), breast carcinoma (MCF7), human lung cancer (A549), human colon cancer (Colo205) and pancreatic cancer cells (Capan2 and MiaPaCa2). A tumor targeting fusion protein (dsFv3-beta-lactamase) was also used in conjunction with cephem-based M(3)N 7 and its potency toward K562, MCF7, A549, Colo205, Capan2, and MiaPaCa2 was found to approach that of the free M(3)N (4). In the presence of dsFv3-beta-lactamase, tumor cells were found to be much more susceptible to conjugate 7 than normal human embryonic lung (HEL) cells and normal fibroblasts (Hef522). These notions provide a new approach to the use of nordihydroguaiaretic acid (NDGA) and its derivatives for antitumor therapy. 相似文献
76.
Gorczyca W Weisberger J Liu Z Tsang P Hossein M Wu CD Dong H Wong JY Tugulea S Dee S Melamed MR Darzynkiewicz Z 《Cytometry》2002,50(3):177-190
T-cell lymphoproliferative disorders are among the most challenging diagnoses in hematopathology. Unlike the more common B-cell disorders, in which clonality is often readily discernible by surface immunoglobulin light chain restriction, there is no specific immunophenotypic signature that is diagnostic of a clonal T-cell population. Immunophenotypic criteria that are helpful in the diagnosis of T-cell neoplasms include T-cell subset antigen restriction, anomalous T-cell subset antigen expression, deletion or diminution of one of the pan T-cell antigens, a precursor T-cell phenotype, and expression of additional markers (e.g., CD30, CD20, major myeloid antigens, and TCRgammadelta). Analysis of the inherent forward and orthogonal light scatter properties of the cell can also provide important diagnostic clues. None of these features is 100% specific, however, for aberrant expression of pan-T antigens may be seen in viral infections, B-cell malignancies, or in reactive changes following administration of certain medications. An increased CD4:CD8 ratio is often observed in Hodgkin's lymphoma. Based on the analysis of 87 neoplastic and 80 control cases, we conclude that flow cytometric features that are most suspicious for malignancy include the loss or markedly dim expression of CD45; complete loss of one or more pan-T antigens; diminished expression of more than two pan-T antigens in conjunction with altered light scatter properties; and CD4/CD8 dual-positive or dual-negative expression (except thymic lesions). 相似文献
77.
78.
Containment of biogenic sulfide production in continuous up-flow packed-bed bioreactors with nitrate or nitrite 总被引:1,自引:0,他引:1
Produced water from the Coleville oil field in Saskatchewan, Canada was used to inoculate continuous up-flow packed-bed bioreactors. When 7.8 mM sulfate and 25 mM lactate were present in the in-flowing medium, H(2)S production (souring) by sulfate-reducing bacteria (SRB) was prevented by addition of 17.5 mM nitrate or 20 mM nitrite. Changing the sulfate or lactate concentration of the in-flowing medium indicated that the concentrations of nitrate or nitrite required for containment of souring decreased proportionally with a lowered concentration of the electron donor lactate, while the sulfate concentration of the medium had no effect. Microbial communities were dominated by SRB. Nitrate addition did not give rise to changes in community composition, indicating that lactate oxidation and H(2)S removal were caused by the combined action of SRB and nitrate-reducing, sulfide-oxidizing bacteria (NR-SOB). Apparently the nitrite concentrations formed by these NR-SOB did not inhibit the SRB sufficiently to cause community shifts. In contrast, significant community shifts were observed upon direct addition of high concentrations (20 mM) of nitrite. Strains NO3A and NO2B, two newly isolated, nitrate-reducing bacteria (NRB) emerged as major community members. These were found to belong to the epsilon-division of the Proteobacteria, to be most closely related to Campylobacter lari, and to oxidize lactate with nitrate or nitrite as the electron acceptor. Thus the mechanism of microbial H(2)S removal in up-flow packed-bed bioreactors depended on whether nitrate (SRB/NR-SOB) or nitrite (SRB/NR-SOB as well as NRB) was used. However, the amount of nitrate or nitrite needed to completely remove H(2)S was dictated by the electron donor (lactate) concentration, irrespective of mechanism. 相似文献
79.
Multiplexed genotyping with sequence-tagged molecular inversion probes 总被引:19,自引:0,他引:19
Hardenbol P Banér J Jain M Nilsson M Namsaraev EA Karlin-Neumann GA Fakhrai-Rad H Ronaghi M Willis TD Landegren U Davis RW 《Nature biotechnology》2003,21(6):673-678
We report on the development of molecular inversion probe (MIP) genotyping, an efficient technology for large-scale single nucleotide polymorphism (SNP) analysis. This technique uses MIPs to produce inverted sequences, which undergo a unimolecular rearrangement and are then amplified by PCR using common primers and analyzed using universal sequence tag DNA microarrays, resulting in highly specific genotyping. With this technology, multiplex analysis of more than 1,000 probes in a single tube can be done using standard laboratory equipment. Genotypes are generated with a high call rate (95%) and high accuracy (>99%) as determined by independent sequencing. 相似文献
80.