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131.
Anette Rink Katie Eyer Benjamin Roelofs Kimberly J. Priest Kathleen J. Sharkey-Brockmeier Sudkamon Lekhong Elif K. Karajusuf Jason Bang Martine Yerle Denis Milan Wan-Sheng Liu Craig W. Beattie 《Mammalian genome》2006,17(8):878-885
The IMpRH7000-rad radiation hybrid panel was used to map 2035 expressed sequence tags (ESTs) at a minimum LOD score of 4.0. A total of 134
linkage groups covers 57,192 cR or 78% of the predicted size of the porcine and 71% of the human genome, respectively. Approximately
81% (1649) of the porcine ESTs were annotated against the NCBI nonredundant database; 1422 mapped in silico to a location in build 35.1 of the human genome sequence (HGS) and 1185 to a gene and location in build 35.1 HGS. The map
revealed 40 major breaks in synteny (1.00e
−25 and lower) with the human genome, 37 of which fall within a single chromosome. At this improved level of resolution and coverage,
porcine chromosomes (SSC) 2, 5, 6, 7, 12, and 14 remain “gene-rich” and homologous to human chromosomes (HSA) 17, 19, and
22, while SSC 1, 8, 11, and X have been confirmed to correspond to the “gene-deserts” on HSA 18, 4, 13, and X. 相似文献
132.
Aydin M Gencer M Cetinkaya Y Ozkok E Ozbek Z Kilic G Orken C Tireli H Kara I 《IUBMB life》2006,58(3):165-172
We investigated the association of PON1 55/192 polymorphisms with type, severity and prognosis of stroke and oxidative markers. Paraoxonase1 (PON1), Glutathione Reductase (GSH-Rd) and Malondialdehyde (MDA) levels were measured at day 1 and at day 5 following the onset of stroke. Genotypes were determined by polymerase chain reaction and restriction digestion. The frequencies of QQ and MM genotypes of PON1 192 and PON1 55, respectively, were significantly higher in controls than in patients. However, the allele frequencies of PON1 192 R and PON1 55 L were significantly more frequent in patients compared to controls. The frequency of combined genotype of RR/LL was significantly higher in cardioembolic group than in atherothrombotic group. PON1 activities were significantly diminished in stroke patients compared to controls. In contrast, serum MDA levels were significantly greater in patients than the values in controls. GSH-Rd activity was higher in patients with small lesion and good prognosis than those with large and poor prognosis. Low density lipoprotein (LDL) levels in patients with large lesions were higher than those with small lesions. PON1 55/192 polymorphisms influence activity of the enzyme. PON1 55/192 genotypes have been associated with MDA levels. In conclusion, PON1 genetic variations are associated with risk factors, severity, type and prognosis of stroke and oxidative stress. 相似文献
133.
Yaakov B Ceylan E Domb K Kashkush K 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2012,124(7):1365-1373
Transposable elements (TEs) account for up to 80% of the wheat genome and are considered one of the main drivers of wheat
genome evolution. However, the contribution of TEs to the divergence and evolution of wheat genomes is not fully understood.
In this study, we have developed 55 miniature inverted-repeat transposable element (MITE) markers that are based on the presence/absence
of an element, with over 60% of these 55 MITE insertions associated with wheat genes. We then applied these markers to assess
genetic diversity among Triticum and Aegilops species, including diploid (AA, BB and DD genomes), tetraploid (BBAA genome) and hexaploid (BBAADD genome) species. While
18.2% of the MITE markers showed similar insertions in all species indicating that those are fossil insertions, 81.8% of the
markers showed polymorphic insertions among species, subspecies, and accessions. Furthermore, a phylogenetic analysis based
on MITE markers revealed that species were clustered based on genus, genome composition, and ploidy level, while 47.13% genetic
divergence was observed between the two main clusters, diploids versus polyploids. In addition, we provide evidence for MITE dynamics in wild emmer populations. The use of MITEs as evolutionary markers might
shed more light on the origin of the B-genome of polyploid wheat. 相似文献
134.
Functional architecture of long-range perceptual interactions 总被引:4,自引:0,他引:4
Polat U 《Spatial Vision》1999,12(2):143-162
The pattern of lateral interactions in the primary visual cortex, which has emerged from recent studies, conforms to the grouping rules of similarity, proximity, smoothness and closure. The goal of this paper is to understand the perceptual salience of oriented elements that are specifically organized to form a smooth contour. An overview of recent studies, in combination with new experimental results, is presented here to emphasis the idea that visual responses depend on input from both the center and the surround of the classical receptive field (CRF). It is assumed that normal lateral interactions produce a neuronal network that is formed by two antagonistic mechanisms: (i) excitation, that is spatially organized along the optimal orientation (collinear), and is predominant near the contrast threshold of the neuron, and (ii) inhibition, that is less selective and is distributed diffusely around the cell's response field. Thus, the inputs from the CRF and the anisotropic surround are summated non-linearly. The specificity of the facilitation and suppression along the collinear direction suggests the existence of second-order elongated collinear filters, which may increase the response similarity between neurons responding to elongated stimulus, thus may enhance the perceptual salience of anisotropic configurations such as contours. This causal connection is particularly evident in amblyopes, where abnormal development of the network results in the abnormal perception of contours. 相似文献
135.
Crystal structure of the YgfZ protein from Escherichia coli suggests a folate-dependent regulatory role in one-carbon metabolism 下载免费PDF全文
Teplyakov A Obmolova G Sarikaya E Pullalarevu S Krajewski W Galkin A Howard AJ Herzberg O Gilliland GL 《Journal of bacteriology》2004,186(21):7134-7140
The ygfZ gene product of Escherichia coli represents a large protein family conserved in bacteria to eukaryotes. The members of this family are uncharacterized proteins with marginal sequence similarity to the T-protein (aminomethyltransferase) of the glycine cleavage system. To assist with the functional assignment of the YgfZ family, the crystal structure of the E. coli protein was determined by multiwavelength anomalous diffraction. The protein molecule has a three-domain architecture with a central hydrophobic channel. The structure is very similar to that of bacterial dimethylglycine oxidase, an enzyme of the glycine betaine pathway and a homolog of the T-protein. Based on structural superposition, a folate-binding site was identified in the central channel of YgfZ, and the ability of YgfZ to bind folate derivatives was confirmed experimentally. However, in contrast to dimethylglycine oxidase and T-protein, the YgfZ family lacks amino acid conservation at the folate site, which implies that YgfZ is not an aminomethyltransferase but is likely a folate-dependent regulatory protein involved in one-carbon metabolism. 相似文献
136.
Arslan S Loğoğlu E Oktemer A 《Journal of enzyme inhibition and medicinal chemistry》2006,21(2):211-214
The in vitro antibacterial and antifungal activities of the compounds synthesised from some 1,2,3,5-tetrahalogeno benzenes in presence of sodium piperidide and sodium pyrrolidide (2,6-dipiperidino-1,4-dihalogenobenzenes; 2,6-dipyrrolidino-1,4-dibromobenzene; 2,4,6-tripyrrolidino chlorobenzene; and 1,3-dipyrrolidino benzene) were investigated. The in vitro antimicrobial activities were screened against the standard strains: Staphylococcus aureus ATCC 25923 and Bacillus subtilis ATCC 6633 as Gram positive, Yersinia enterocolitica ATCC 1501, Escherichia coli ATCC 11230 and Klebsiella pneumoniae as Gram negative, and Candida albicans as yeast-like fungus. Compounds (3, 5, 6, 7) inhibited the growth of all the test strains at MIC values of 32-512 microg/ml. None of the four compounds (1, 2,4,8) studied showed antimicrobial activity against any of the test strains within the MIC range 0.25-512 micro/ml. 相似文献
137.
Olive leaf extract modulates permethrin induced genetic and oxidative damage in rats 总被引:3,自引:0,他引:3
Permethrin is a common synthetic chemical, widely used as an insecticide in agriculture and other domestic applications. The previous reports indicated that permethrin is a highly toxic synthetic pyrethroid pesticide to human and environmental health. Therefore, the present experiment was undertaken to determine the effectiveness of olive leaf extract in modulating the permethrin induced genotoxic and oxidative damage in rats. The animals used were broadly divided into four (A, B, C and D) experimental groups. Group A rats served as control animals and received distilled water intraperitoneally (n = 5). Groups B and C rats received intraperitoneal injections of permethrin (60 mg kg−1 b.w) and olive leaf extract (500 mg kg−1 b.w), respectively. Group D rats received permethrin (60 mg kg−1 b.w) plus olive leaf extract (500 mg kg−1 b.w). Rats were orally administered their respective feed daily for 21 days. At the end of the experiment rats were anesthetized and serum and bone marrow cell samples were obtained. Genotoxic damage was assessed by micronucleus and chromosomal aberration assays. Total antioxidant capacity and total oxidant status were also measured in serum samples to assess oxidative status. Treatment of Group B with permethrin resulted in genotoxic damage and increased total oxidant status levels. Permethrin treatment also significantly decreased (P < 0.05) total antioxidant capacity level when compared to Group A rats. Group C rats showed significant increases (P < 0.05) in total antioxidant capacity level and no alterations in cytogenetic parameters. Moreover, simultaneous treatments with olive leaf extract significantly modulated the toxic effects of permethrin in Group D rats. It can be concluded that olive leaf extract has beneficial influences and could be able to antagonize permethrin toxicity. As a result, this investigation clearly revealed the protective role of olive leaf extract against the genetic and oxidative damage by permethrin in vivo for the first time. 相似文献
138.
Rosolino Bumbalo Marilena Lieber Lisa Schroeder Yasemin Polat Heinz Breer Joerg Fleischer 《Cellular and molecular neurobiology》2017,37(4):729-742
Neurons of the Grueneberg ganglion respond to cool temperatures as well as to distinct odorants and extend axonal processes to the olfactory bulb of the brain. Analyses of transgenic mice, in which Grueneberg ganglion neurons and their axons are labeled, revealed that these axons innervated nine distinct glomeruli distributed in a characteristic topographical pattern in dorsal, lateral, ventral, and medial regions of rather posterior areas in the bulb. To assess activation of these glomeruli (hereinafter designated as Grueneberg glomeruli) upon stimulation of Grueneberg ganglion neurons, mice were exposed to the odorant 2,3-dimethylpyrazine (2,3-DMP) and the expression of the activity-dependent marker c-Fos in juxtaglomerular cells of the relevant glomeruli was monitored. It was found that all of these glomeruli were activated, irrespective of their localization in the bulb. To verify that the activation of juxtaglomerular cells in Grueneberg glomeruli was indeed based on stimulation of Grueneberg ganglion neurons, the 2,3-DMP-induced responses in these glomeruli were investigated in mice lacking the cyclic nucleotide-gated channel CNGA3 which is critical for chemo- and thermosensory signal transduction in Grueneberg ganglion neurons. This approach revealed that elimination of CNGA3 led to a reduction of the odorant-induced activity in Grueneberg glomeruli, indicating that the activation of these glomeruli is based on a preceding stimulation of the Grueneberg ganglion. Analyzing whether Grueneberg glomeruli in the bulb might also process thermosensory information, it was found that upon exposure to coolness, Grueneberg glomeruli were activated. Investigating mice lacking CNGA3, the activation of these glomeruli by cool temperatures was attenuated. 相似文献
139.
Two new species of the mite genus Zercon C. L. Koch, 1836 have been found: Zercon ekizi sp. n. and Zercon emirdagicus sp. n. are described and illustrated from female specimens collected in Afyonkarahisar and Kütahya provinces, Turkey. The similarities and differences between the related species are discussed.
http://www.zoobank.org/urn:lsid:zoobank.org:pub:7388D199-2D1D-49F7-9747-4F49E8810067 相似文献
140.
Koray Oktay Leyla Polat Köse Kıvılcım Şendil Claudiu T. Supuran 《Journal of enzyme inhibition and medicinal chemistry》2016,31(6):939-945
The synthesis of (Z)-4-oxo-4-(arylamino)but-2-enoic acid (4) derivatives containing structural characteristics that can be used for the synthesis of several active molecules, is presented. Some of the butenoic acid derivatives (4a, 4c, 4e, 4i, 4j, 4k) are synthesized following literature procedures and at the end of the reaction. In addition, structures of all synthesized derivatives (4a–4m) were determined by 1H-NMR, 13C-NMR and IR spectroscopy. Carbonic anhydrase is a metalloenzyme involved in many crucial physiologic processes as it catalyzes a simple but fundamental reaction, the reversible hydration of carbon dioxide to bicarbonate and protons. Significant results were obtained by evaluating the enzyme inhibitory activities of these derivatives against human carbonic anhydrase hCA I and II isoenzymes (hCA I and II). Butenoic acid derivatives (4a–4m) strongly inhibited hCA I and II with Kis in the low nanomolar range of 1.85?±?0.58 to 5.04?±?1.46?nM against hCA I and in the range of 2.01?±?0.52 to 2.94?±?1.31?nM against hCA II. 相似文献