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311.
Lemey P Salemi M Wang B Duffy M Hall WH Saksena NK Vandamme AM 《FEMS immunology and medical microbiology》2003,39(2):125-132
The site stripping for clock detection procedure was implemented in the recently developed maximum likelihood framework for estimating evolutionary rates and divergence times in measurably evolving populations. The method was used to investigate the effect of rate variability on estimating divergence times in non-clock-like trees for human immunodeficiency viruses and hepatitis C viruses. We validate our approach by comparing dated coalescent nodes in molecular phylogenies with known dates of transmission. Our method was able to rapidly recover clock-like behavior and to indicate the presence and direction of a bias when estimates of divergence times using the unstripped data were flawed. 相似文献
312.
A simple,high-yield method for obtaining multipotential mesenchymal progenitor cells from trabecular bone 总被引:10,自引:0,他引:10
Tuli R Seghatoleslami MR Tuli S Wang ML Hozack WJ Manner PA Danielson KG Tuan RS 《Molecular biotechnology》2003,23(1):37-49
In vitro cultures of primary, human trabecular bone-derived cells represent a useful system for investigation of the biology
of osteoblasts. Our recent discovery of the multilineage mesenchymal differentiation potential of trabecular bone-derived
cells suggests the potential application of these cells as mesenchymal progenitors for tissue repair and regeneration. Such
applications are crucially dependent on efficient cellisolation protocols to yield cells that optimally proliferate and differentiate.
In this study, we describe a simple, high-yield procedure, requiring minimal culture expansion, for the isolation of mesenchymal
progenitor cells from human trabecular bone. Moreover, these cells retain their ability to differentiate along multiple mesenchymal
lineages through successive subculturing. Cell populations isolated and cultured as described here allow the efficient acquisition
of a clinically significant number of cells, which may be used as the cell source for tissue-engineering applications. 相似文献
313.
Unniappan S Peter RE 《American journal of physiology. Regulatory, integrative and comparative physiology》2004,286(6):R1093-R1101
We studied the in vitro and in vivo effects of octanoylated goldfish ghrelin peptides (gGRL-19 and gGRL-12) on luteinizing hormone (LH) and growth hormone (GH) release in goldfish. gGRL-19 and gGRL-12 at picomolar doses stimulated LH and GH release from dispersed goldfish pituitary cells in perifusion and static incubation. Incubation of pituitary cells for 2 h with 10 nM gGRL-12 and 1 or 10 nM gGRL-19 increased LH-beta mRNA expression, whereas only 10 nM gGRL-19 increased GH mRNA expression. Somatostatin-14 abolished the stimulatory effects of ghrelin on GH release from dispersed pituitary cells in perifusion and static culture. The GH secretagogue receptor antagonist d-Lys(3)-GHRP-6 inhibited the ghrelin-induced LH release, whereas no effects were found on stimulation of GH release by ghrelin. Intracerebroventricular injection of 1 ng/g body wt of gGRL-19 or intraperitoneal injection of 100 ng/g body wt of gGRL-19 increased serum LH levels at 60 min after injection, whereas significant increases in GH levels were found at 15 and 30 min after these treatments. Our results indicate that, in addition to its potent stimulatory actions on GH release, goldfish ghrelin peptides have the novel function of stimulating LH release in goldfish. 相似文献
314.
SCH 56592 is a novel triazole antifungal agent that is active both orally and intravenously in animal models of infection. This compound is in Phase II-III clinical trials for the treatment of systemic fungal infections. SCH 56592 is a single enantiomer with four stereogenic centers; therefore, it was necessary to evaluate the possible chiral inversion of this drug candidate in animals and humans. Thus, chiral high-performance liquid chromatographic (HPLC) methods have been developed to separate SCH 56592 from its diastereomers and to evaluate its chiral inversion in rats, dogs, cynomolgus monkeys, and humans. Chiral HPLC analysis involved the use of a Chiralcel OD column set at 39 degrees C with a mobile phase of hexane-ethanol-diethylamine and a fluorescence detector set at an excitation wavelength of 270 nm and an emission wavelength of 390 nm. Plasma or serum samples were subjected to solid phase extraction on a C(2) cartridge followed by HPLC analysis. The method was sensitive with a limit of quantitation of 0.1 microg/ml in dog serum. The linearity was satisfactory, as shown by correlations of >0.997 and by visual examination of the calibration curves. The precision and accuracy were satisfactory, as indicated by coefficients of variation (CV) ranging from 1.1 to 12.1% and bias values ranging from -11.0 to 9.0%. Chiral HPLC analysis indicated that SCH 56592 was not subjected to chiral inversion in rats, dogs, cynomolgus monkeys, and humans. 相似文献
315.
Adam Kamei Kanishendranath Sarker Siddhartha Das Gouranga Datta Suraj Goldar 《Archives Of Phytopathology And Plant Protection》2013,46(19-20):1039-1048
AbstractTomato (Lycopersicon esculentum Mill.) is a cosmopolitan vegetable and widely cultivated in almost all the countries of the world including India. Irreversible investment – production ratio for tomato cultivation in recent Indian agricultural systems arise the question, is there any biotic backlogs responsible for such a production loss. Our present investigation is based on this fact. Target leaf spot disease of tomato is caused by Corynespora cassiicola, a serious and emerging disease in India. Prolonged real time surveillance of this disease on tomato from 2010–11 to 2016–17, reflects some remarkable features of pathogenic progress in Gangetic alluvial region of West Bengal. This pathogen is the natural barrier for tomato production with a disease severity ranged between 35% and 58% which ultimately causes tremendous loss of tomato foliage and fruits. C. cassiicola was identified on the basis of morpho-cultural (ITCC Accession No. 7542) and molecular characterization (Genbank Accession No. KJ767193). Homology searching of internal transcribed spacer region of CcHaTom isolate was highly matched with Genbank Accession No. KP666184 (Cynodondactylon/India), AB873045 (Vitex negundo/India) and JN541214 (Malvaviscus concinnus/USA) with 95% similarity. Phylogenetic analysis established that KJ767193 and C. cassiicola retrieved sequences were conspecific from a common ancestral origin, which supports its neighbourhood with this fungal pathogen. Optimum temperature between 24 and 25?°C, coupled with 80–85% relative humidity triggered the disease progress. From the emerging scenario, C. cassiicola infecting tomato is the real threat for indigenous cultivars. 相似文献
316.
Marie-Line Goulet David Olagnier Zhengyun Xu Suzanne Paz S. Mehdi Belgnaoui Erin I. Lafferty Valérie Janelle Meztli Arguello Marilene Paquet Khader Ghneim Stephanie Richards Andrew Smith Peter Wilkinson Mark Cameron Ulrich Kalinke Salman Qureshi Alain Lamarre Elias K. Haddad Rafick Pierre Sekaly Suraj Peri Siddharth Balachandran Rongtuan Lin John Hiscott 《PLoS pathogens》2013,9(4)
317.
318.
Wenyue Du Ajeetha Josephrajan Suraj Adhikary Timothy Bowles Anja-Katrin Bielinsky Brandt F. Eichman 《PloS one》2013,8(7)
Minichromosome maintenance protein 10 (Mcm10) is an essential eukaryotic DNA-binding replication factor thought to serve as a scaffold to coordinate enzymatic activities within the replisome. Mcm10 appears to function as an oligomer rather than in its monomeric form (or rather than as a monomer). However, various orthologs have been found to contain 1, 2, 3, 4, or 6 subunits and thus, this issue has remained controversial. Here, we show that self-association of Xenopus laevis Mcm10 is mediated by a conserved coiled-coil (CC) motif within the N-terminal domain (NTD). Crystallographic analysis of the CC at 2.4 Å resolution revealed a three-helix bundle, consistent with the formation of both dimeric and trimeric Mcm10 CCs in solution. Mutation of the side chains at the subunit interface disrupted in vitro dimerization of both the CC and the NTD as monitored by analytical ultracentrifugation. In addition, the same mutations also impeded self-interaction of the full-length protein in vivo, as measured by yeast-two hybrid assays. We conclude that Mcm10 likely forms dimers or trimers to promote its diverse functions during DNA replication. 相似文献
319.
Homocysteine thiolactone is a toxic metabolite produced from homocysteine by amino-acyl t-RNA synthetase in error editing reaction. The basic cause of toxicity of homocysteine thiolactone is believed to be due to the adduct formation with lysine residues (known as protein N-homocysteinylation) leading to protein aggregation and loss of enzyme function. There was no data available until now that showed the effect of homocysteine thiolactone on the native state structural changes that led to aggregate formation. In the present study we have investigated the time dependent structural changes due to homocysteine thiolactone induced modifications on three different proteins having different physico-chemical properties (cytochrome-c, lysozyme and alpha lactalbumin). We discovered that N-homocysteinylation leads to the formation of molten globule state—an important protein folding intermediate in the protein folding pathway. We also found that the formation of the molten globule state might be responsible for the appearance of aggregate formation. The study indicates the importance of protein folding intermediate state in eliciting the homocysteine thiolactone toxicity. 相似文献
320.
Importin-alpha-16 is a translocon-associated protein involved in sorting membrane proteins to the nuclear envelope 总被引:1,自引:0,他引:1
Saksena S Summers MD Burks JK Johnson AE Braunagel SC 《Nature structural & molecular biology》2006,13(6):500-508
A viral inner nuclear membrane-sorting motif sequence (INM-SM) was used to identify proteins that recognize integral membrane proteins destined for the INM. Herein we describe importin-alpha-16, a membrane-associated isoform of Spodoptera frugiperda importin-alpha that contains the C-terminal amino acid residues comprising armadillo helical-repeat domains 7-10. In the endoplasmic reticulum (ER) membrane, importin-alpha-16 is adjacent to the translocon protein Sec61alpha. Importin-alpha-16 cross-links to the INM-SM sequence as it emerges from the ribosomal tunnel and remains adjacent to the INM-SM after INM-SM integration into the ER membrane and release from the translocon. Cross-linking results suggest that importin-alpha-16 discriminates between INM- and non-INM-directed proteins. Thus, it seems that during and after cotranslational membrane integration, importin-alpha-16 is involved in the trafficking of integral membrane proteins to the INM. 相似文献