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71.
72.
Szczerbowska-Boruchowska M Dumas P Kastyak MZ Chwiej J Lankosz M Adamek D Krygowska-Wajs A 《Archives of biochemistry and biophysics》2007,459(2):241-248
Synchrotron radiation based-Fourier transform infrared microspectroscopy was used for preliminary investigation of the chemical composition and morphologies of the human substantia nigra of brain between normal and Parkinson's diseased tissues. The studies were carried out for thin tissue sections, focusing more particularly on nerve cell bodies, that are affected in Parkinson's disease (PD). The major spectral differences between normal (control) and PD tissues were identified at the following vibrational frequencies: 2930, 2850, 1655, 1380, 1236, 1173 and 1086 cm(-1). The infrared imaging of these biochemical markers show that for control cases the protein and nucleic acids functional groups (bands at: approximately 3300, approximately 3100, approximately 1655, approximately 1545, approximately 1240, approximately 1080 cm(-1)) are located mainly in the cell body. The spatial distribution of the band at 1740 cm(-1) (ester carbonyl stretching band) is quite dissimilar to the others, while it exhibits a minimal concentration in the cell body area. Contrarily, in PD samples, no clear evidence of variation of any of the vibrational fingerprint between cell body and the surrounding was noticed. Moreover, decrease of protein to lipid ratio as well as increase of amide I/amide II ratio were observed for PD case. The preliminary results strengthen the hypothesis that PD is a multietiological disorder. Moreover, the reported results clearly indicate that, in addition to a distinct visual observation, the diseased nerve cells exhibits change of their biochemical composition. It suggests that disturbances of normal functioning of SN neurons appear before their morphological atrophy. 相似文献
73.
74.
Monika Rakoczy-Trojanowska Paweł Krajewski Jan Bocianowski Małgorzata Schollenberger Wojciech Wakuliński Paweł Milczarski Piotr Masojć Małgorzata Targońska-Karasek Zofia Banaszak Katarzyna Banaszak Waldemar Brukwiński Wacław Orczyk Andrzej Kilian 《Plant Molecular Biology Reporter》2017,35(3):366-378
Rye is a crop with relatively high resistance to biotic and abiotic stresses. However, the resistance to brown rust (Puccinia recondita f. sp. secalis) and pre-harvest sprouting are still not satisfactory. High α-amylase activity is also among the main disadvantages of this species. Therefore, effective tools, e.g. molecular markers, allowing precise and environmentally independent selection of favourable alleles are desirable. In the present study, two kinds of association mapping—genome-wide association mapping (GWAM) based on sequences of DArTSeq markers and candidate gene association mapping (CGAM) based on sequences of ScBx genes—were chosen for development of molecular markers fulfilling these criteria. The analysed population consisted of 149 diverse inbred lines (DILs). Altogether, 67 and 11 single nucleotide polymorphisms (SNPs) identified in, respectively, GWAM and CGAM, were significantly associated with the investigated traits: 2 SNPs with resistance to brown rust, 71 SNPs with resistance to pre-harvest sprouting and 5 SNPs with α-amylase activity in the grain. Fifteen SNPs were stable across all environments. The highest number (13) of environmentally stable SNPs was associated with pre-harvest sprouting resistance. The test employing the Kompetitive Allele Specific PCR method proved the versatility of four markers identified in both GWAM and CGAM. 相似文献
75.
Intrinsic factors drive spatial genetic variation in a highly vagile species,the wedge‐tailed eagle Aquila audax,in Tasmania
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Christopher P. Kozakiewicz Scott Carver Jeremy J. Austin Jill M. Shephard Christopher P. Burridge 《Journal of avian biology》2017,48(7):1025-1034
Knowledge of dispersal in a species, both its quantity and the factors influencing it, are crucial for our understanding of ecology and evolution, and for species conservation. Here we quantified and formally assessed the potential contribution of extrinsic factors on individual dispersal in the threatened Tasmanian population of wedge‐tailed eagle Aquila audax. As successful breeding by these individuals appears strongly related to habitat, we tested the effect of landscape around sampling sites on genetic diversity and spatial genetic variation, as these are influenced by patterns of dispersal. Similarly, we also tested whether habitat intervening sampling sites could explain spatial genetic variation. Twenty microsatellites were scored, but only a small proportion of spatial genetic variation (4.6%) could be explained by extrinsic factors, namely habitat suitability and elevation between sites. However, significant clinal genetic variation was evident across Tasmania, which we explain by intrinsic factors, likely high natal philopatry and occasional long‐distance dispersal. This study demonstrates that spatial genetic variation can be detected in highly vagile species at spatial scales that are small relative to putative dispersal ability, although here there was no substantial relationship with landscape factors tested. 相似文献
76.
Reply to “Clinical and therapeutic implications of BRAF mutation heterogeneity in metastatic melanoma” by Mesbah Ardakani et al.
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77.
Saeed Rayati Niloofar Torabi Sajjad Mohebbi Anna Kozakiewicz 《Inorganica chimica acta》2008,361(5):1239-1245
Three N2O2 tetradentate Schiff base ligands (H2L1-3) were prepared by reaction of 1,2-propylenediamine and appropriate aldehyde and ketone and characterized by FT-IR, 1H and 13C NMR. The vanadyl complexes were synthesized by treating an ethanolic solution of the appropriate ligand and one equivalent of VO(acac)2 to yield VOL1-3. These oxovanadium (IV) complexes were characterized on the basis of their FT-IR, UV-Vis spectroscopy and elemental analysis. The crystal structure of VOL3 has been determined. The metal center in VOL3 is a deformed tetragonal pyramidal N2O3 coordination sphere. These complexes are used as catalyst for the selective epoxidation of olefins. High selectivity of epoxidation for cyclooctene observed from oxidation data. The catalytic activity increases as the number of electron-donor groups increases, and the catalytic selectivity is varied by changing the substituents on the ligands. The catalytic system described here is an efficient and inexpensive method for the oxidation of olefins, with the advantages of high activity, selectivity, re-usability and short reaction time. 相似文献
78.
Iveta Ondrejkovi?ová Jerzy Mroziński Julia K?ak Zofia Olejnik 《Inorganica chimica acta》2008,361(8):2483-2490
The iron(II) compound of formula [Fe(NCS)2(dena)2]n (dena = N,N′-diethylnicotinamide) has been prepared by the reaction between iron(III) thiocyanate and dena in ethanol solution. The complex was characterized by elemental analysis, spectral and magnetic measurements. Single-crystal X-ray diffraction methods show that the complex, crystallizing in the triclinic space group, undergoes a phase transition between 220 K and 230 K, connected with the doubling of cell volume. Crystal structures at 230 K (1a; HT phase) and 150 K (1b; LT phase) are described and a transition mechanism is discussed. In both phases the compound has an extended chain structure, in which the neutral molecule of N,N′-diethylnicotinamide acts as a bridging ligand binding through pyridine N atom to one centre and through amide O atom to the neighbouring Fe centre. The Fe2+ ion has a slightly distorted trans-octahedral environment with FeO2N4 chromophore, and all Fe-O and Fe-N bonds in the typical for high-spin iron(II) compounds range. Variable-temperature magnetic susceptibility data in the temperature range 1.8-300 K show that iron(II) is high-spin S = 2(5T2g) and as a result effects due to zero-field splitting are anticipated at low temperatures. The IR spectrum suggested the coordination of N,N′-diethylnicotinamide to the central atom of iron(II) as a bridging ligand and NCS group as a monodentate ligand. 相似文献
79.
Anna Zaczek Anna Brzostek Ewa Augustynowicz-Kopec Zofia Zwolska Jaroslaw Dziadek 《BMC microbiology》2009,9(1):10-8
Background
Rifampin is a first line antituberculosis drug active against bacilli in logarithmic and stationary phase, which interferes with RNA synthesis by binding to bacterial RNA polymerase. Tubercle bacilli achieve resistance to rifampin by accumulation of mutations in a short-81 bp region of the rpoB gene. Among many mutations identified in the rpoB gene, few were verified by molecular genetic methods as responsible for resistance to rifampin (RMP). 相似文献80.
Wojtasik A Majchrzak M Adamus-Bialek W Augustynowicz-Kopec E Zwolska Z Dziadek J Parniewski P 《Journal of microbiological methods》2011,85(1):28-32
Diseases that are caused by non-tuberculous mycobacteria (NTM) continue to pose difficult clinical problems, and the epidemiological aspect of NTM-caused diseases is of great importance. In the case of Mycobacterium gordonae there is no adequate genotyping scheme. Here we present a potential rapid and reproducible genetic assay that uses trinucleotide repeat sequence-based PCR (TRS-PCR) for genotyping M. gordonae. The proposed method constitutes a useful single-primer PCR screen for genotyping this species. Among 10 TRS-containing primers, after applying (CAC)4-based PCR to 36 strains of M. gordonae, we found a discriminatory index of 0.975. The accuracy of this analysis was supported by a reasonable reproducibility of 92%. These results were compared with the Enterobacterial Repetitive Intergenic Consensus Sequences (ERIC)-PCR typing scheme which had lower discriminatory index of 0.93 and its reproducibility was only 86.3%. 相似文献