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1.
The fadBA operon in the fatty acid β-oxidation pathway of P. putida KCTC1639 was blocked to induce a metabolic flux of the intermediates to the biosynthesis of medium chain-length PHA (mcl-PHA).
Succinate at 150 mg l−1 stimulated cell growth and also the biosynthesis of medium chain-length-polyhydroxyalkanoate. pH-stat fed-batch cultivation
of the fadA knockout mutant P. putida KCTC1639 was carried out for 60 h, in which mcl-PHA reached 8 g l−1 with a cell dry weight of 10.3 g l−1. 相似文献
2.
Michelle J. Pena Andreas Heinzel Georg Heinze Alaa Alkhalaf Stephan J. L. Bakker Tri Q. Nguyen Roel Goldschmeding Henk J. G. Bilo Paul Perco Bernd Mayer Dick de Zeeuw Hiddo J. Lambers Heerspink 《PloS one》2015,10(5)
ObjectiveWe aimed to identify a novel panel of biomarkers predicting renal function decline in type 2 diabetes, using biomarkers representing different disease pathways speculated to contribute to the progression of diabetic nephropathy.ResultsPatients’ average age was 63.5 years and baseline eGFR was 77.9 mL/min/1.73m2. The average rate of eGFR decline was -2.0 ± 4.7 mL/min/1.73m2/year. When modeled on top of established risk markers, the biomarker panel including matrix metallopeptidases, tyrosine kinase, podocin, CTGF, TNF-receptor-1, sclerostin, CCL2, YKL-40, and NT-proCNP improved the explained variability of eGFR decline (R2 increase from 37.7% to 54.6%; p=0.018) and improved prediction of accelerated eGFR decline (C-index increase from 0.835 to 0.896; p=0.008).ConclusionsA novel panel of biomarkers representing different pathways of renal disease progression including inflammation, fibrosis, angiogenesis, and endothelial function improved prediction of eGFR decline on top of established risk markers in type 2 diabetes. These results need to be confirmed in a large prospective cohort. 相似文献
3.
Silvas J Prince Li Song Dan Qiu Joao V Maldonado dos Santos Chenglin Chai Trupti Joshi Gunvant Patil Babu Valliyodan Tri D Vuong Mackensie Murphy Konstantinos Krampis Dominic M Tucker Ruslan Biyashev Anne E Dorrance MA Saghai Maroof Dong Xu J Grover Shannon Henry T Nguyen 《BMC genomics》2015,16(1)
Background
Root system architecture is important for water acquisition and nutrient acquisition for all crops. In soybean breeding programs, wild soybean alleles have been used successfully to enhance yield and seed composition traits, but have never been investigated to improve root system architecture. Therefore, in this study, high-density single-feature polymorphic markers and simple sequence repeats were used to map quantitative trait loci (QTLs) governing root system architecture in an inter-specific soybean mapping population developed from a cross between Glycine max and Glycine soja.Results
Wild and cultivated soybean both contributed alleles towards significant additive large effect QTLs on chromosome 6 and 7 for a longer total root length and root distribution, respectively. Epistatic effect QTLs were also identified for taproot length, average diameter, and root distribution. These root traits will influence the water and nutrient uptake in soybean. Two cell division-related genes (D type cyclin and auxin efflux carrier protein) with insertion/deletion variations might contribute to the shorter root phenotypes observed in G. soja compared with cultivated soybean. Based on the location of the QTLs and sequence information from a second G. soja accession, three genes (slow anion channel associated 1 like, Auxin responsive NEDD8-activating complex and peroxidase), each with a non-synonymous single nucleotide polymorphism mutation were identified, which may also contribute to changes in root architecture in the cultivated soybean. In addition, Apoptosis inhibitor 5-like on chromosome 7 and slow anion channel associated 1-like on chromosome 15 had epistatic interactions for taproot length QTLs in soybean.Conclusion
Rare alleles from a G. soja accession are expected to enhance our understanding of the genetic components involved in root architecture traits, and could be combined to improve root system and drought adaptation in soybean.Electronic supplementary material
The online version of this article (doi:10.1186/s12864-015-1334-6) contains supplementary material, which is available to authorized users. 相似文献4.
5.
Henri‐Obadja Kumada Jeffrey‐Tri Nguyen Taeko Kakizawa Koushi Hidaka Tooru Kimura Yoshio Hayashi Yoshiaki Kiso 《Journal of peptide science》2011,17(8):569-575
HTLV‐I is a debilitating and/or lethal retrovirus that causes HTLV‐I‐associated myelopathy/tropical spastic paraparesis, adult T‐cell leukemia and several inflammatory diseases. HTLV‐I protease is an aspartic retropepsin involved in HTLV‐I replication and its inhibition could treatHTLV‐I infection. A recombinant L40I mutant HTLV‐I protease was designed and obtained from Escherichia coli, self‐processingand purification by ion‐exchange chromatography. The protease was refolded by a one‐step dialysis and recovered activity. The cleavage efficiency of the [Ile40]HTLV‐I protease was at least 300 times higher for a fluorescent substratethan that of our previously reported recombinant His‐tagged non‐mutated HTLV‐I protease. In addition, we designed and synthesized a substrate containing a highly fluorescent Mca moiety in the fragment before the scissile bond, and a chromogenic p‐nitrophenylalanine moiety after the scissile bond that greatly amplified spectrometry detection and improved the HTLV‐I protease inhibition potency assay. The HTLV‐I protease inhibition assay with the [Ile40]HTLV‐I protease and fluorogenic substrate requires distinctively less protease, substrate, inhibitor and assay time than our previous methods. This means our new assay is more cost‐effective and more time‐efficient while being reproducible and less labor‐intensive. Copyright © 2011 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
6.
S A Adesanya M T Martin B Hill V Dumontet M Van Tri T Sévenet M Pa?s 《Phytochemistry》1999,51(8):1039-1041
Chemical investigation of the methanolic fraction of Lepisanthes rubiginosa bark has led to the isolation and characterisation of a new tetrasaccharide derivative of farnesol named rubiginoside along with known triterpenoid saponins. 相似文献
7.
We present a mathematical bioeconomic model of a fishery with a variable price. The model describes the time evolution of the resource, the fishing effort and the price which is assumed to vary with respect to supply and demand. The supply is the instantaneous catch while the demand function is assumed to be a monotone decreasing function of price. We show that a generic market price equation (MPE) can be derived and has to be solved to calculate non trivial equilibria of the model. This MPE can have 1, 2 or 3 equilibria. We perform the analysis of local and global stability of equilibria. The MPE is extended to two cases: an age-structured fish population and a fishery with storage of the resource. 相似文献
8.
Major locus and other novel additive and epistatic loci involved in modulation of isoflavone concentration in soybean seeds 总被引:4,自引:0,他引:4
Gutierrez-Gonzalez JJ Vuong TD Zhong R Yu O Lee JD Shannon G Ellersieck M Nguyen HT Sleper DA 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2011,123(8):1375-1385
Seeds of soybean [Glycine max (L.) Merr.] accumulate more isoflavones than any tissue of any plant species. In other plant parts, isoflavones are usually
released to counteract the effects of various biotic and abiotic stresses. Because of the benefits to the plant and positive
implications that consumption may have on human health, increasing isoflavones is a goal of many soybean breeding programs.
However, altering isoflavone levels through marker-assisted selection (MAS) has been impractical due to the small and often
environmentally variable contributions that each individual quantitative trait locus (QTL) has on total isoflavones. In this
study, we developed a Magellan × PI 437654 F7-RIL population to construct a highly saturated non-redundant linkage map that encompassed 451 SNP and SSR molecular markers
and used it to locate genomic regions that govern accumulation of isoflavones in the seeds of soybean. Five QTLs were found
that contribute to the concentration of isoflavones, having single or multiple additive effects on isoflavone component traits.
We also validated a major locus which alone accounted for up to 10% of the phenotypic variance for glycitein, and 35–37% for
genistein, daidzein and the sum of all three soybean isoflavones. This QTL was consistently associated with increased concentration
of isoflavones across different locations, years and crosses. It was the most important QTL in terms of net increased amounts
of all isoflavone forms. Our results suggest that this locus would be an excellent candidate to target for MAS. Also, several
minor QTLs were identified that interacted in an additive-by-additive epistatic manner, to increase isoflavone concentration. 相似文献
9.
Tamara Turk Jan Willem Leeuwis Julia Gray Suzy V. Torti Karen M. Lyons Tri Q. Nguyen Roel Goldschmeding 《The journal of histochemistry and cytochemistry》2009,57(7):623-631
Diabetic nephropathy is characterized by decreased expression of bone morphogenetic protein-7 (BMP-7) and decreased podocyte number and differentiation. Extracellular antagonists such as connective tissue growth factor (CTGF; CCN-2) and sclerostin domain-containing-1 (SOSTDC1; USAG-1) are important determinants of BMP signaling activity in glomeruli. We studied BMP signaling activity in glomeruli from diabetic patients and non-diabetic individuals and from control and diabetic CTGF+/+ and CTGF+/− mice. BMP signaling activity was visualized by phosphorylated Smad1, -5, and -8 (pSmad1/5/8) immunostaining, and related to expression of CTGF, SOSTDC1, and the podocyte differentiation markers WT1, synaptopodin, and nephrin. In control and diabetic glomeruli, pSmad1/5/8 was mainly localized in podocytes, but both number of positive cells and staining intensity were decreased in diabetes. Nephrin and synaptopodin were decreased in diabetic glomeruli. Decrease of pSmad1/5/8 was only partially explained by decrease in podocyte number. SOSTDC1 and CTGF were expressed exclusively in podocytes. In diabetic glomeruli, SOSTDC1 decreased in parallel with podocyte number, whereas CTGF was strongly increased. In diabetic CTGF+/− mice, pSmad1/5/8 was preserved, compared with diabetic CTGF+/+ mice. In conclusion, in human diabetic nephropathy, BMP signaling activity is diminished, together with reduction of podocyte markers. This might relate to concomitant overexpression of CTGF but not SOSTDC1. (J Histochem Cytochem 57:623–631, 2009) 相似文献
10.
Bos R Windono T Woerdenbag HJ Boersma YL Koulman A Kayser O 《Phytochemical analysis : PCA》2007,18(2):118-122
An optimized HPLC method with photodiode array detection was developed and applied to analyse the curcuminoids curcumin, demethoxycurcumin, and bis-demethoxycurcumin in rhizomes of Curcuma mangga Val &. v. Zijp, C. heyneana Val. & v. Zijp, C. aeruginosa Roxb. and C. soloensis Val. (Zingiberaceae), indigenous to Indonesia. The method was validated with an isocratic system, a short run time of 10 min and a baseline separation. The curcuminoid content was 0.18-0.47% for C. mangga, 0.98-3.21% for C. heyneana, 0.02-0.03% for C. aeruginosa and 0.40% for C. soloensis. 相似文献