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301.
302.
Stancanelli R Crupi V De Luca L Ficarra P Ficarra R Gitto R Guardo M Iraci N Majolino D Tommasini S Venuti V 《Bioorganic & medicinal chemistry》2008,16(18):8706-8712
The (R,S)-2-acetyl-1-(4'-chlorophenyl)-6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline ((R,S)-1) was previously identified as a potent non-competitive AMPA receptor antagonist able to prevent epileptic seizures and reduce AMPA-induced current in electrophysiological experiments. Through the enantiomeric resolution of racemate by chiral HPLC we already demonstrated that the (R)-1 enantiomer was the eutomer. Considering the poor water solubility, these compounds have been complexed with beta-cyclodextrin (beta-CyD). The effect of beta-cyclodextrin on the spectral features of molecules was quantitatively investigated, in fully aqueous medium by phase-solubility study and the obtained diagrams suggested that it forms complexes with a molar ratio 1:1. The binding constant (K((R)-1)=15889M(-1), K((R,S)(-1))=1079 M(-1)) and the complexation efficiency (CE) were calculated. Then the solid complexes in 1:1 molar ratio were prepared by the co-precipitation method and the FTIR-ATR measurements were carried out in order to confirm the host-guest interactions that drive the complexation process, by monitoring the significant differences of the spectra of the complexes with respect to those of the corresponding physical mixtures in the same molar ratio. The experimental data have been compared with molecular modelling studies and we confirmed our hypothesis. 相似文献
303.
Patrizia Romano Angela Capece Vincenza Serafino Rossana Romaniello Cinzia Poeta 《World journal of microbiology & biotechnology》2008,24(9):1797-1802
The principal agent in winemaking is the yeast Saccharomyces cerevisiae, which is characterized by a significant strain biodiversity. Here we report the characterization of 80 wild S. cerevisiae strains, isolated from grapes of different varieties in southern Italy, for genetic and technological variability. By PCR
amplification with M13 primer a significant polymorphism was recorded and 12 different biotypes were identified among the
strains. The specific strain-pattern could be used to follow the dynamics of different biotypes during the fermentation process.
The analysis of experimental wines obtained by inoculated fermentations with the 80 strains showed significant differences
among the wines. The level of each compound was a function of the strain performing the fermentative process. The main variables
for the strain differentiation were the production of acetaldehyde and acetic acid, which ranged from 53 to 282 mg/l and from
0.20 to 1.88 g/l, respectively. Selected strains were tested in fermentation with two different grape musts, yielding experimental
wines differing in the levels of secondary compounds and polyphenol content, in function of the interaction “grape must composition/yeast
strain”. This finding has an applicative value for the potentiality of utilizing the resource of strain variability as a tool
to individuate suitable starter cultures, which are able to complement and optimize grape quality. 相似文献
304.
305.
Vincenza Calabrò Emanuele Ricca Maria Gabriela De Paola Stefano Curcio Gabriele Iorio 《Bioprocess and biosystems engineering》2010,33(6):701-710
In this paper, the reaction of enzymatic trans-esterification of glycerides with ethanol in a reaction medium containing hexane
at a temperature of 37 °C has been studied. The enzyme was Lipase from Mucor miehei, immobilized on ionic exchange resin, aimed at achieving high catalytic specific surface and recovering, regenerating and
reusing the biocatalyst. A kinetic analysis has been carried out to identify the reaction path; the rate equation and kinetic
parameters have been also calculated. The kinetic model has been validated by comparison between predicted and experimental
results. Mass transport resistances estimation was undertaken in order to verify that the kinetics found was intrinsic. Model
potentialities in terms of reactors design and optimization are also shown. 相似文献
306.
Extreme resistance to cucumber mosaic virus (CMV) in transgenic tomato expressing one or two viral coat proteins 总被引:2,自引:0,他引:2
Kaniewski Wojciech Ilardi Vincenza Tomassoli Laura Mitsky T. Layton J. Barba Marina 《Molecular breeding : new strategies in plant improvement》1999,5(2):111-119
For the production of broad commercial resistance to cucumber mosaic virus (CMV) infection, tomato plants were transformed
with a combination of two coat protein (CP) genes, representing both subgroups of CMV. The CP genes were cloned from the CMV-D
strain and Italian CMV isolates (CMV-22 of subgroup I and CMV-PG of subgroup II) which have been shown to produce severe disease
symptoms. Four plant transformation vectors were constructed: pMON18774 and pMON18775 (CMV-D CP), pMON18831 (CMV-PG CP) and
pMON18833 (CMV-22 CP and CMV-PG CP). Transformed R0 plants were produced and lines were selected based on the combination
of three traits: CMV CP expression at the R0 stage, resistance to CMV (subgroup I and/or II) infection in growth chamber tests
in R1 expressing plants, and single transgene copy, based on R1 segregation. The results indicate that all four vector constructs
generated plants with extremely high resistant to CMV infection. The single and double gene vector construct produced plants
with broad resistance against strains of CMV from both subgroups I and II at high frequency. The engineered resistance is
of practical value and will be applied for major Italian tomato varieties.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
307.
We measured the 31P[1H] Nuclear Overhauser Effect (NOE) as a function of temperature and of 1H irradiation frequency, the linewidth as a function of temperature and the relaxation time T1 above and below the thermal transition temperature, of the 31P-NMR signal in sonicated liposomes of 1,2-dimiristoyl-3-sn-phosphatidylcholine (DMPC), 1,2-dipalmitoyl-3-sn-phosphatidylcholine (DPPC) and 1,2-dimiristoyl-3-sn-phosphatidylcholine (DSPC). The same measurements were repeated in the presence of high molecular weight dextrans. They strongly reduce the NOE and produce longer relaxation times T1. According to the current models, we were able to evaluate, in the different situations, the correlation time of the internal motion τG and the distance r between interacting groups in the region of the polar head groups. While the first parameter changes abruptly through the phase transition and under the effect of dextrans, the latter does not appear modified in any case. These results are discussed in terms of a conformational change of the phosphocholine head groups. 相似文献
308.
Tomassoli Laura Ilardi Vincenza Barba Marina Kaniewski Wojciech 《Molecular breeding : new strategies in plant improvement》1999,5(2):121-130
Since the summer of 1993, transgenic tomato plants expressing the coat protein (CP) genes of cucumber mosaic cucumovirus have
been tested under field conditions to assess the level of resistance and agronomic performance. Trials were performed in different
areas in Italy and the target virus in the majority of tests was spread naturally by the indigenous aphid populations. Twenty-three
homozygous lines of variety UC82B, transformed to contain four different CP genes of CMV, were evaluated. The lines were preselected
for CP expression, single gene copy, and virus resistance in growth chamber experiments. In general, CMV resistance was confirmed
under field conditions though resistance in the field was less effective than what was observed in growth chamber experiments.
The resistance observed in multi-year and multi-location experiments is of commercial value for several of the most resistant
lines. Engineered resistance upon transfer to Italian varieties by breeding or direct transformation will be used in tomato
production in Italy or elsewhere.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
309.
310.
The distribution of the adrenaline and noradrenaline chromaffin cells in the adrenal glands of 10 members of the family Cordylidae have been examined. In the genus Gerrhosaurus, all the catecholamine cells lie on the surface of the adrenal gland, forming a continuous envelope of one or two layers of cells that mainly contain noradrenaline (NA). In the genus Platysaurus, the chromaffin envelope is intermittent. There are relatively large tracts of interspersed interrenal tissue containing some adrenaline cells (A). Islets of chromaffin cells are scattered between these interrenal tracts. In the genus Pseudocordylus and the genus Cordylus, the superficial chromaffin cells tend to gather into a multilayered dorsal mass, containing mainly NA cells. Inside the interrenal parenchyma, there are always numerous chromaffin islets, containing mainly A cells. 相似文献