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61.
Hu Y Xing L Thomason JR Xiang J Ipek M Guler S Li H Sabatini J Chockalingam P Reifenberg E Sheldon R Morris EA Georgiadis KE Tam S 《Bioorganic & medicinal chemistry letters》2011,21(22):6800-6803
Design, synthesis and structure-activity relationship of a series of biphenylsulfonamido-3-methylbutanoic acid based aggrecanase-1 inhibitors are described. In addition to robust aggrecanase-1 inhibition, these compounds also exhibit potent MMP-13 activity. In cell-based cartilage explants assay compound 48 produced 87% inhibition of proteoglycan degradation at 10 μg/mL. Good pharmacokinetic properties were demonstrated by 46 with a half-life of 6h and bioavailability of 23%. 相似文献
62.
Novel short peptides isolated from phage display library inhibit vascular endothelial growth factor activity 总被引:1,自引:0,他引:1
Erdag B Balcioglu KB Kumbasar A Celikbicak O Zeder-Lutz G Altschuh D Salih B Baysal K 《Molecular biotechnology》2007,35(1):51-63
Signal transduction through the vascular endothelial growth factor (VEGF)-VEGF receptor (VEGFR) pathway has a pivotal importance
in angiogenesis, and has therefore become a prime target in antitumor therapy. In search for peptides antagonizing VEGF binding
to its receptors, we screened a random heptamer library displayed on phage for peptides that bind the whole VEGF165 molecule and inhibit VEGF dependent human umbilical vein endothelial cell (HUVEC) proliferation. Two selected peptides with
sequences WHLPFKC and WHKPFRF were synthesized. Biacore and matrix-assisted laser desorption/ionization time-of-flight mass
spectrometry analysis indicated that these peptides bind the VEGF homodimer in a concentration-dependent manner, with micromolar
affinity, and with a 2:1 peptide: VEGF stoichiometry. They inhibited HUVEC proliferation in vitro by 77 and 55%, respectively.
Taken together, our results indicate that these peptides could be potent inhibitors of angiogenesis. Furthermore, we show
that the peptide-VEGF binding properties can be quantified, a prerequisite for the further optimization of binders. 相似文献
63.
Ipek G. Kulahci Christine M. Drea Daniel I. Rubenstein Asif A. Ghazanfar 《Proceedings. Biological sciences / The Royal Society》2014,281(1784)
Individual recognition can be facilitated by creating representations of familiar individuals, whereby information from signals in multiple sensory modalities become linked. Many vertebrate species use auditory–visual matching to recognize familiar conspecifics and heterospecifics, but we currently do not know whether representations of familiar individuals incorporate information from other modalities. Ring-tailed lemurs (Lemur catta) are highly visual, but also communicate via scents and vocalizations. To investigate the role of olfactory signals in multisensory recognition, we tested whether lemurs can recognize familiar individuals through matching scents and vocalizations. We presented lemurs with female scents that were paired with the contact call either of the female whose scent was presented or of another familiar female from the same social group. When the scent and the vocalization came from the same individual versus from different individuals, females showed greater interest in the scents, and males showed greater interest in both the scents and the vocalizations, suggesting that lemurs can recognize familiar females via olfactory–auditory matching. Because identity signals in lemur scents and vocalizations are produced by different effectors and often encountered at different times (uncoupled in space and time), this matching suggests lemurs form multisensory representations through a newly recognized sensory integration underlying individual recognition. 相似文献
64.
Akçakaya P Azeroglu B Even I Ates O Turker H Ongen G Topal-Sarikaya A 《Molecular biology reports》2012,39(4):5009-5016
Sarcoidosis (SA) is an immune-mediated multisystemic disorder of unknown etiology characterized by the accumulation of lymphocytes,
mononuclear phagocytes and epithelioid cell granulomas involved in different organs and tissues. The belief that genetics
contribute to SA etiology is supported by twin studies, disease clustering in families and racial differences in incidence
rates. Involvements of SLC11A1 in macrophage function and activation, makes it an attractive candidate gene for immune-mediated and infectious diseases.
We investigated the association between SA and four polymorphisms of the SLC11A1 gene, including a single nucleotide change in intron 4 (INT4); a nonconservative single-base substitution at codon 543 (D543N);
a TGTG deletion in the 3′ untranslated region; and the functional (GT)n repeat polymorphism in the 5′ region, in 95 Turkish SA patients and 150 healthy controls, by using amplification refractory
mutation system–polymerase chain reaction and sequencing. We found significant association between SA and INT4 G/C allele
frequency (P = 0.0000; odds ratio 2.75; 95% confidence interval 1.68–4.52) and 5′(GT)n allele 2/3 frequency (P = 0.0000; odds ratio 2.69; 95% confidence interval 1.61–4.47) suggesting that SLC11A1 might be a plausible candidate gene for SA. 相似文献
65.
Production of alkaline alpha-amylase employing our laboratory isolate, Bacillus sp., under solid state fermentation, was optimized. The effect of wheat bran and lentil husk was examined. Lentil husk exhibited the highest enzyme production. The appropriate incubation time, inoculum size, moisture level, and buffer solution level were determined. Maximum yields of 216,000 and 172,800 U/g were achieved by employing lentil husk and wheat bran as substrates in 0.1 M carbonate/bicarbonate buffer at pH 10.0 with 30% initial moisture level at 24 h. Inoculum size and buffer solution level were found to be 20% and 1:0.5 for two solid substrates. 相似文献
66.
The production of extracellular α-amylase by thermotolerant Bacillus subtilis was studied in solid state fermentation (SSF). The effect of wheat bran (WB) and rice husk (RH) was examined. The appropriate incubation period, moisture level, particle size and inoculum concentration was determined. Maximum yields of 159,520 and 21,760 U g−1 were achieved by employing WB and RH as substrates in 0.1 M phosphate buffer at pH 7 with 30% initial moisture content at 24 and 48 h. Particle size and inoculum concentration were found to be 1000 μm, 20% and 500 μm, 15% for WB and RH, respectively. Enzyme yield was 7.3-fold higher with WB medium compared with RH. 相似文献
67.
The homogeneous bovine heart mitochondrial high-molecular-mass oxaloacetate keto-enol tautomerase [(1988) Biochim. Biophys. Acta 936, 10-19] is shown to be an iron-sulfur protein as revealed by the enzyme spectral properties and direct chemical determination of non-heme iron and acid-labile sulfur. The protein is capable of catalysing the aconitase reaction after treatment with ferrous ions under anaerobic conditions. Treatment of the 'activated' protein with N-ethylmaleimide results in the simultaneous irreversible loss of the oxaloacetate keto-enol tautomerase and aconitase activities. The effects of some substrates and inhibitors on both activities show that the same catalytic site is involved in the oxaloacetate tautomerase and aconitase reactions. It is concluded that the protein previously described as a 80 kDa oxaloacetate keto-enol tautomerase is inactive aconitase. 相似文献
68.
Kenneth Wasmund D. Ipek Kurtböke Kathryn A. Burns & David G. Bourne 《FEMS microbiology ecology》2009,68(2):142-151
This study examined the diversity of Bacteria, Archaea and in particular aerobic methanotrophs associated with a shallow (84 m) methane seep in the tropical Timor Sea, Australia. Seepage of thermogenic methane was associated with a large carbonate hardground covered in coarse carbonate-rich sediments and various benthic organisms such as solitary corals. The diversity of Bacteria and Archaea was studied by analysis of cloned 16S rRNA genes, while aerobic methanotrophic bacteria were quantified using real-time PCR targeting the α-subunit of particulate methane monooxygenase ( pmoA ) genes and diversity was studied by analysis of cloned pmoA genes. Phylogenetic analysis of bacterial and archaeal 16S rRNA genes revealed diverse and mostly novel phylotypes related to sequences previously recovered from marine sediments. A small number of bacterial 16S rRNA gene sequences were related to aerobic methanotrophs distantly related to the genera Methylococcus and Methylocaldum . Real-time PCR targeting pmoA genes showed that the highest numbers of methanotrophs were present in surface sediments associated with the seep area. Phylogenetic analysis of pmoA sequences revealed that all phylotypes were novel and fell into two large clusters comprised of only marine sequences distantly related to the genera Methylococcus and Methylocaldum that were clearly divergent from terrestrial phylotypes. This study provides evidence for the existence of a novel microbial diversity and diverse aerobic methanotrophs that appear to constitute marine specialized lineages. 相似文献
69.
Ziver T Yuksel P Ipek G Yekeler I Bayramoglu Z Tireli E Saribas S Aslan M Yalvac SD Ozdomanic I Torlak Z Dirican A Torun MM Kocazeybek B 《The new microbiologica》2010,33(3):233-242
Helicobacter pylori is thought to be related to atherosclerosis and aneurysm development. We aimed to detect virulance factors of H. pylori and examine the potential etiopathogenetic relationship between aortic aneurysm and H. pylori, 58 abdominal aortic aneurysm (AAA) and 38 ascending aortic aneurysm (AsAA) cases and 57 Healty control group (HCG) were included. We investigated H. pylori IgG by ELISA and virulance factors by Western-Blot (WB) method. No difference was found between AAA (67.24%), AsAA (73.68%) and HCG (57.89%) for H. pylori IgG (p > 0.05). A significant difference was found between AsAA (78.95%) and HCG (57.89%) for H.pylori IgG (p < 0.05) by ELISA and a significant difference was found only between AsAA (100%) and HCG (37.5%) for H. pylori IgG in the 45-55 age group by WB. A statistically significant difference was found between AAA and AsAA for VacA and CagA + VacA and CagA + VacA + UreA antigens and also a significant difference was found between AsAA and HCG for CagA + UreA antigens (p < 0.05). Finally, we suggest that H. pylori VacA has a more important role than CagA in the development of two aneurysms especially in ruptured AAA. New extended studies detecting H. pylori DNA are needed to detect the aetiopathogenesis between aneurysm types and H. pylori. 相似文献
70.
In spite of the widespread use of proteins (casein, peptone, etc.) and protein fragments as a substrate for the proteolytic enzymes, a substrate prepared from dyes that adsorb onto appropriate materials, such as wool and cotton, are also used for enzyme activity determination. In the point of view of this thought, it was our aim to develop the substrates which are easily and economically obtainable and also environmentally safer for the frequently used proteolytic enzymes, such as subtilisin carlsberg, trypsin, chymotrypsin, and protease type XVI and, if possible, to prepare the specific substrate at least for one of these enzymes. For this aim, wool was dyed with natural dyes such as juglone, lawsone, berberine, and quercetin. The optimum pH, incubation time, and agitation rate were determinated. The results indicate that, of all the tested enzymes on wool-dye complex as an insoluble substrate, the most appropriate complex was found to be wool-lawsone complex. 相似文献