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131.
132.
Priscylla Andrade Volkart Rodrigo Benedetti Gassen Bettina Mühlen Nogueira Bárbara Nery Porto José Eduardo Vargas André Arigony Souto 《Bioorganic & medicinal chemistry letters》2017,27(15):3238-3242
Resveratrol (Rsv) is widely reported to possess anticarcinogenic properties in a plethora of cellular and animal models having limited toxicity toward normal cells. In the molecular level, Rsv can act as a suppressive agent for several impaired signaling pathways on cancer cells. However, Fukuhara and Miyata have shown a non-proteic reaction of Rsv, which can act as a prooxidant agent in the presence of copper (Cu), causing cellular oxidative stress accompanied of DNA damage. After this discovery, the complex Rsv-Cu was broadly explored as an antitumor mechanism in multiples tumor cell lines. The aim of the study is to explore the anticarcinogenic behavior of resveratrol–Cu(II) complex in MCF-7 cell line.Selectivity of Rsv binding to Cu ions was analyzed by HPLC and UV–VIS. The cells were enriched with concentrations of 10 and 50 µM CuSO4 solution and treated with 25 µM of Rsv. Copper uptake after enrichment of cells, as its intracellular distribution in MCF-7 line, was scanned by ICP-MS and TEM-EDS. Cell death and intracellular ROS production were determined by flow cytometry.Different from the extracellular model, no relationship of synergy between Rsv–Cu(II) and reactive oxidative species (ROS) production was detected in vitro. ICP-MS revealed intracellular copper accumulation to both chosen concentrations (0.33 ± 0.09 and 1.18 ± 0.13 ppb) but there is no promotion of cell death by Rsv–Cu(II) complex. In addition, significant attenuation of ROS production was detected when cells were exposed to CuSO4 after Rsv treatment, falling from 7.54% of ROS production when treated only with Rsv to 3.07 and 2.72% with CuSO4.Based on these findings antitumor activity of resveratrol when in copper ions presence, is not mediated by Rsv-Cu complex formation in MCF-7 human cell line, suggesting that the antitumoral reaction is dependent of a cancer cellular model. 相似文献
133.
Érika Lika Ida Ronivaldo Rodrigues da Silva Tássio Brito de Oliveira Tatiane Beltramini Souto Juliana Abigail Leite André Rodrigues 《Preparative biochemistry & biotechnology》2017,47(3):282-290
Filamentous fungi secrete diverse peptidases with different biochemical properties, which is of considerable importance for application in various commercial sectors. In this study, we describe the isolation of two fungal species collected from the soil of decayed organic matter: Aspergillus fischeri and Penicillium citrinum. In a submerged bioprocess, we observed better peptidase production with the fungus P. citrinum, which reached a peak production at 168?h with 760?U/mL, in comparison with the fungus A. fischeri, which reached a peak production at 72?h with 460?U/mL. In both situations, the fermentative medium contained 0.5% crushed feathers as a source of nitrogen. On performing biochemical characterization, we detected two alkaline serine peptidases: The one secreted by P. citrinum had optimal activity at pH 7.0 and at 45°C, while the one secreted by A. fischeri had optimal activity in pH 6.5–8 and at 55–60°C. Metallic ions were effective in modulating these peptidases; in particular, Cu2+ promoted negative modulation of both peptidases. The peptidases were stable and functional under conditions of nonionic surfactants, temperatures up to 45°C for 1?h, and incubation over a wide pH range. In addition, it was observed that both peptidases had the capacity to hydrolyze collagen and performed well in removing an egg protein stain when supplemented into a commercial powder detergent; this was especially true for the peptidase from P. citrinum. 相似文献
134.
135.
In order to evaluate the significance of injecting vitamins complexes and stimulants minutes before soccer games and its role in spread of hepatitis C virus (HCV) we interviewed and tested 40 ex-soccer players, who played professionally in Mato Grosso, Brazil, between 1970 and 1989. Five players were found anti-HCV positive with enzyme-immunoassay. When re-tested by immunoblot (RIBA), three of these five were confirmed to be positive reacting. The anti-HCV positivity (7.5%) was higher than usually found among blood donors (0.9%) in this region (p < 0.01). None of the players had had prior history of any risk factor that might indicate HCV exposure. We suggest that the common practice of soccer players in the inner part of Brazil in the 70's and 80's, to receive fortifying injections, often with shared syringes, may place ex-soccer players in a potential risk group for HCV infection and warrants further investigation and attention by public health workers. 相似文献
136.
Soria JM Blangero J Souto JC Martínez-Sánchez E Martínez-Marchán E Coll I Tirado I Cercós A Almasy L Fontcuberta J 《Human genetics》2002,111(1):59-65
As part of the GAIT (genetic analysis of idiopathic thrombophilia) project, we analyzed polymorphisms in the factor V (FV) gene to assess their role as genetic determinants of normal phenotypic variation of hemostasis-related traits in a Spanish population. During the analysis of exon 13 polymorphisms, we detected an abnormal PCR-amplified fragment in some members of the GAIT19 family. Direct sequence analysis revealed a deletion of 108 bp in eight out of 20 individuals in this family. This deletion removes exactly 36 amino acids from the B domain of FV; thus it does not alter the reading frame of the sequence. Among the deleted amino acids there is the 4070A>G polymorphism (H1299R), which could affect the level or function of FV. In addition, in the same family we identified three novel DNA variants (L1257I, Q1317Q and T1327T) in exon 13 of the F5 gene. Despite these variants, we did not detect any differences either in the coagulant or anticoagulant traits, or in the plasma protein levels involved in the blood coagulation cascade, between the carriers compared with their non-carrier relatives. From these results, we can conclude that the mutant allele is expressed and the resultant protein is functional. Moreover, it is unlikely that the 4070A>G polymorphism, within the deletion, and the novel DNA variants alter the functional properties of the mature FV protein. Further analyses of this naturally occurring mutation and the novel DNA variants should yield useful information for the understanding of the function of the B domain of FV. 相似文献
137.
Iha MH Martinez AS Bonato PS 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2002,767(1):1-9
In this study we evaluated a liquid-liquid extraction procedure and a solid-phase extraction procedure for sample preparation for the enantioselective analysis of atenolol in plasma and urine by high-performance liquid chromatography. A Chiralcel OD-H column was used for the resolution of atenolol enantiomers with hexane-ethanol (85:15, v/v) plus 0.1% diethylamine as the mobile phase. In the liquid-liquid extraction procedure, atenolol was extracted from alkalinized body fluids with 5 ml chloroform-2-propanol (4:1, v/v). In the solid-phase extraction procedure, atenolol was isolated from plasma using a C8 column and methanol. Both extraction procedures were efficient in recovering atenolol and removing endogenous interferents. The RSDs and deviation from nominal values were lower than 10% for both within-day and between-day assays. The results show that there were no statistically significant differences in between-day variation. The t-test showed that there were no significant differences between the real concentrations and the determined concentrations. The limit of quantitation was 10 ng/ml and the linear range was 10-5,000 ng/ml for both methods. These methods can be used in pharmacokinetic studies. 相似文献
138.
Genetic susceptibility to thrombosis and its relationship to physiological risk factors: the GAIT study. Genetic Analysis of Idiopathic Thrombophilia
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Souto JC Almasy L Borrell M Blanco-Vaca F Mateo J Soria JM Coll I Felices R Stone W Fontcuberta J Blangero J 《American journal of human genetics》2000,67(6):1452-1459
Although there are a number of well-characterized genetic defects that lead to increased risk of thrombosis, little information is available on the relative importance of genetic factors in thrombosis risk in the general population. We performed a family-based study of the genetics of thrombosis in the Spanish population to assess the heritability of thrombosis and to identify the joint actions of genes on thrombosis risk and related quantitative hemostasis phenotypes. We examined 398 individuals in 21 extended pedigrees. Twelve pedigrees were ascertained through a proband with idiopathic thrombosis, and the remaining pedigrees were randomly ascertained. The heritability of thrombosis liability and the genetic correlations between thrombosis and each of the quantitative risk factors were estimated by means of a novel variance component method that used a multivariate threshold model. More than 60% of the variation in susceptibility to common thrombosis is attributable to genetic factors. Several quantitative risk factors exhibited significant genetic correlations with thrombosis, indicating that some of the genes that influence quantitative variation in these physiological correlates also influence the risk of thrombosis. Traits that exhibited significant genetic correlations with thrombosis included levels of several coagulation factors (factors VII, VIII, IX, XI, XII, and von Willebrand), tissue plasminogen activator, homocysteine, and the activated protein C ratio. This is the first study that quantifies the genetic component of susceptibility to common thrombosis. The high heritability of thrombosis risk and the significant genetic correlations between thrombosis and related risk factors suggest that the exploitation of correlated quantitative phenotypes will aid the search for susceptibility genes. 相似文献
139.
We report studies on the interaction of α-melanocyte stimulating hormone (α-MSH) and a synthetic analogue (MSH-I) with reverse
micelles prepared from the amphiphilic sodium bis(2-ethylhexyl)sulfosuccinate in isooctane. The tripeptide lysyl-tryptophyl-
lysine and the isolated amino acid tryptophan were also investigated as simpler compounds interacting with the micelles. Tryptophan
fluorescence parameters (spectral position of emission band, anisotropy, and lifetime decay) demonstrated that in the presence
of reverse micelles the environment around the fluorophore is less polar and more rigid than bulk water. Those parameters
are sensitive to the changes induced in the micelles by the presence of water. In large micelles having a water/amphiphile
molar ratio above 10, the modifications detected by fluorescence are small and the location of the fluorophore is not affected
by a further increase in the concentration of the bulk water. The results, with additional support from quenching experiments,
indicated that the different compounds occupy different positions in the large reverse micelles, but in any case they are
in the interface region, without dispersing into the bulk water. From decay associated spectra, conformations were identified
showing different degrees of tryptophan exposition to polar and nonpolar local environments. The conformation related to the
long lifetime has its tryptophan more exposed to water while that associated to the intermediate lifetime has that residue
stabilized in nonpolar media. The native hormone α-MSH and the analogue MSH-I present similar conformations in dry micelles.
However, in buffer and in the large hydrated micelles, differences in conformations are evident, and could be related to the
different physiological activity of the peptides.
Received: 4 August 1999 / Revised version: 17 December 1999 / Accepted: 4 January 2000 相似文献
140.
Sibylle M Gomes Martin Bodner Luis Souto Bettina Zimmermann Gabriela Huber Christina Strobl Alexander W R?ck Alessandro Achilli Anna Olivieri Antonio Torroni Francisco C?rte-Real Walther Parson 《BMC genomics》2015,16(1)