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61.
Kim CG Lamichhane J Song KI Nguyen VD Kim DH Jeong TS Kang SH Kim KW Maharjan J Hong YS Kang JS Yoo JC Lee JJ Oh TJ Liou K Sohng JK 《Archives of microbiology》2008,189(5):463-473
The four overlapping cosmids from the rubradirin producer, Streptomyces achromogenes var rubradiris NRRL 3061, have 58 ORFs within a 105.6 kb fragment. These ORFs harbored essential genes responsible for the formation and
attachment of four distinct moieties, along with the genes associated with regulatory, resistance, and transport functions.
The PKS (rubA) and glycosyltransferase (rubG2) genes were disrupted in order to demonstrate a complete elimination of rubradirin production. The rubradirin biosynthetic
pathway was proposed based on the putative functions of the gene products, the functional identification of sugar genes, and
the mutant strains.
The GeneBank accession number for the sequence reported in this paper is AJ871581. 相似文献
62.
Molecular cytogenetic analysis and resequencing of contactin associated protein-like 2 in autism spectrum disorders 总被引:1,自引:0,他引:1 下载免费PDF全文
Bakkaloglu B O'Roak BJ Louvi A Gupta AR Abelson JF Morgan TM Chawarska K Klin A Ercan-Sencicek AG Stillman AA Tanriover G Abrahams BS Duvall JA Robbins EM Geschwind DH Biederer T Gunel M Lifton RP State MW 《American journal of human genetics》2008,82(1):165-173
Autism spectrum disorders (ASD) are a group of related neurodevelopmental syndromes with complex genetic etiology. We identified a de novo chromosome 7q inversion disrupting Autism susceptibility candidate 2 (AUTS2) and Contactin Associated Protein-Like 2 (CNTNAP2) in a child with cognitive and social delay. We focused our initial analysis on CNTNAP2 based on our demonstration of disruption of Contactin 4 (CNTN4) in a patient with ASD; the recent finding of rare homozygous mutations in CNTNAP2 leading to intractable seizures and autism; and in situ and biochemical analyses reported herein that confirm expression in relevant brain regions and demonstrate the presence of CNTNAP2 in the synaptic plasma membrane fraction of rat forebrain lysates. We comprehensively resequenced CNTNAP2 in 635 patients and 942 controls. Among patients, we identified a total of 27 nonsynonymous changes; 13 were rare and unique to patients and 8 of these were predicted to be deleterious by bioinformatic approaches and/or altered residues conserved across all species. One variant at a highly conserved position, I869T, was inherited by four affected children in three unrelated families, but was not found in 4010 control chromosomes (p = 0.014). Overall, this resequencing data demonstrated a modest nonsignificant increase in the burden of rare variants in cases versus controls. Nonetheless, when viewed in light of two independent studies published in this issue of AJHG showing a relationship between ASD and common CNTNAP2 alleles, the cytogenetic and mutation screening data suggest that rare variants may also contribute to the pathophysiology of ASD, but place limits on the magnitude of this contribution. 相似文献
63.
S. Rajesh Eiichi Ami Tomoya Kotake Tooru Kimura Yoshio Hayashi Yoshiaki Kiso 《Bioorganic & medicinal chemistry letters》2002,12(24):4567-3617
Z- and Fmoc-L-tetrahydrofuranylglycines have been obtained from L-vinylglycine through dipolar cycloaddition reaction, and its Fmoc derivative has been applied in the synthesis of modified S9 and S10 substrates of HIV-1 protease. These compounds mostly acted as strong inhibitors, rather than substrates, of the protease, probably due to the favourable interactions of the tetrahydrofuranylglycine moiety at the S(2) site. 相似文献
64.
Ami Klein Sharon Ramcharitar Nevena Christeff Erik Nisbett-Brown Emmanuel Nunez Aaron Malkin 《In vitro cellular & developmental biology. Animal》1991,27(4):307-311
Summary These authors attempted to test the effect of anticoagulants on lymphocytes viability by reproducing the procedure used for
lymphocyte isolation for various immunologic tests in which blood specimens are allowed to stay at room temperature for 2
h before lymphocytes are isolated. Blood was obtained with three different anticoagulants i.e. heparin, citrate, and CPDA
(citrate, phosphate, dextrose, and adenine). Plasma was lyophilized and extracted with ethanol. Dried ethanol extracts were
suspended in medium (RPMI 1640+10% fetal bovine serum) and incubated with a lymphocyte cell line (MOLT-4). After 24 h of incubation
the viability of cells was examined. The following death rates of the cells were observed: heparin −63±4.6% (mean±SEM), citrate
−27±6.7%, and CPDA 6.2±0.6% (P<0.0005). A significant correlation was found between these results and changes in the concentrations of free fatty acids
in the extracts. These results emphasize the importance of choosing the right anticoagulant when the viability of lymphocytes
is obligatory. 相似文献
65.
Peter Tsvetkov Nadav Myers Raz Eliav Yaarit Adamovich Tzachi Hagai Julia Adler Ami Navon Yosef Shaul 《The Journal of biological chemistry》2014,289(16):11272-11281
The 26S proteasome is the end point of the ubiquitin- and ATP-dependent degradation pathway. The 26S proteasome complex (26S PC) integrity and function has been shown to be highly dependent on ATP and its homolog nucleotides. We report here that the redox molecule NADH binds the 26S PC and is sufficient in maintaining 26S PC integrity even in the absence of ATP. Five of the 19S proteasome complex subunits contain a putative NADH binding motif (GxGxxG) including the AAA-ATPase subunit, Psmc1 (Rpt2). We demonstrate that recombinant Psmc1 binds NADH via the GxGxxG motif. Introducing the ΔGxGxxG Psmc1 mutant into cells results in reduced NADH-stabilized 26S proteasomes and decreased viability following redox stress induced by the mitochondrial inhibitor rotenone. The newly identified NADH binding of 26S proteasomes advances our understanding of the molecular mechanisms of protein degradation and highlights a new link between protein homeostasis and the cellular metabolic/redox state. 相似文献
66.
67.
Segregative cell division and the cytoskeleton in two species of the genus Struvea (Cladophorales,Ulvophyceae, Chlorophyta) 下载免费PDF全文
Kazuo Okuda Satoko Sekida Ami Hasebe Misa Iwabuchi Mitsunobu Kamiya Tasuku Hishinuma 《Phycological Research》2016,64(4):219-229
The detailed segregative cell division (SCD) processes and changes in the arrangement of cortical microtubules and actin filaments were examined in two species of Struvea. SCD was initiated by the appearance of annular constrictions along the lateral side of a mother cell. The constrictions decreased in diameter, became thin, tubular in shape, and pinched the protoplasm of the mother cell into several protoplasmic sections. The protoplasmic sections expanded and developed into daughter cells, which appressed each other, and were arranged in a single row. Lateral branches protruded from the upper parts of the daughter cells. The protoplasm of the lateral branches was divided by secondary SCDs and was distributed amongst the new daughter cells. SCD and lateral branch formation were essential for morphogenesis in Struvea. Cortical microtubules were arranged parallel and longitudinally to the cell axis before SCD. When SCD was initiated, there was considerable undulation of the cortical microtubules and several transverse bundles appeared in the cytoplasmic zone where annular constrictions occurred. A microtubule‐disrupting drug (amiprophos methyl) inhibited SCD. Actin filaments maintained reticulate patterns before and during SCD. These results demonstrated that SCD in Struvea species was quite distinct from that in Dictyosphaeria cavernosa reported previously. 相似文献
68.
Antonino Natalello P. Patrizia Mangione Sofia Giorgetti Riccardo Porcari Loredana Marchese Irene Zorzoli Annalisa Relini Diletta Ami Giulia Faravelli Maurizia Valli Monica Stoppini Silvia M. Doglia Vittorio Bellotti Sara Raimondi 《The Journal of biological chemistry》2016,291(18):9678-9689
The amyloidogenic variant of β2-microglobulin, D76N, can readily convert into genuine fibrils under physiological conditions and primes in vitro the fibrillogenesis of the wild-type β2-microglobulin. By Fourier transformed infrared spectroscopy, we have demonstrated that the amyloid transformation of wild-type β2-microglobulin can be induced by the variant only after its complete fibrillar conversion. Our current findings are consistent with preliminary data in which we have shown a seeding effect of fibrils formed from D76N or the natural truncated form of β2-microglobulin lacking the first six N-terminal residues. Interestingly, the hybrid wild-type/variant fibrillar material acquired a thermodynamic stability similar to that of homogenous D76N β2-microglobulin fibrils and significantly higher than the wild-type homogeneous fibrils prepared at neutral pH in the presence of 20% trifluoroethanol. These results suggest that the surface of D76N β2-microglobulin fibrils can favor the transition of the wild-type protein into an amyloid conformation leading to a rapid integration into fibrils. The chaperone crystallin, which is a mild modulator of the lag phase of the variant fibrillogenesis, potently inhibits fibril elongation of the wild-type even once it is absorbed on D76N β2-microglobulin fibrils. 相似文献
69.
Fli-1, an Ets-related transcription factor, regulates erythropoietin-induced erythroid proliferation and differentiation: evidence for direct transcriptional repression of the Rb gene during differentiation. 下载免费PDF全文
70.