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71.
Giacomo Zara Maurizio Ciani Paola Domizio Severino Zara Marilena Budroni Adriana Carboni Ilaria Mannazzu 《Annals of microbiology》2014,64(1):403-406
When inoculated in association with Saccharomyces cerevisiae, the yeast Lachancea thermotolerans determines a reduction of volatile acidity and an increase in the production of glycerol, 2-phenylethanol, and polysaccharides. Moreover, L. thermotolerans is a natural L-lactic acid producer, thus it contributes to wine acidification and microbiological stabilization. In view of its utilization in winemaking, a culture-independent PCR-based method was developed for the detection of L. thermotolerans during wine fermentations. This method, which utilizes species-specific PCR primer pairs that anneal to intron 2 of the mitochondrial COX1 gene, is rapid and reliable, and detects L. thermotolerans in wine at 104 cells/ml and with a S. cerevisiae/L. termotholerans ratio of 1,000/1. 相似文献
72.
Annamaria Sandomenico Valeria Severino Angela Chambery Annalia Focà Giuseppina Focà Claudio Farina Menotti Ruvo 《Molecular biotechnology》2013,54(3):983-995
Intravenous immunoglobulin are important bio-therapeutics used in the replacement therapy for primary and secondary immunodeficiencies, chronic inflammatory disorders and several autoimmune haematologic disorders. Currently, a number of immunoglobulin intravenous (IVIG) products have been approved by the Food and Drug Administration (FDA) and are available commercially. It is known that small differences in the manufacturing processes as well as in the formulations may affect their clinical efficacy and tolerability. Therefore, given the complexity of the multi-step process required for the isolation of IVIG from human plasma, it is necessary to ensure a rigorous quality control of final products. We show here that a set of different bioanalytical techniques can be conveniently used to comparatively characterize, at a quantitative and qualitative level, different lots of IVIG preparations and to unveil randomly occurring impurities which can also affect the overall product stability. We have used circular dichroism, surface plasmon resonance and two-dimensional electrophoresis (2DE), and have demonstrated that this combination of bioanalytical approaches is very useful to improve the quality control of antibodies and to monitor the reliability of the IVIG manufacturing process. 相似文献
73.
Marina GM Viturino Jamil M Neto Flvia F Bajano Sueli MS Costa Alicia B Roque Gessica FS Borges Galina Ananina Priscila HH Rim Flvio M Medina Fernando F Costa Jos PC de Vasconcellos Mnica B de Melo 《Experimental biology and medicine (Maywood, N.J.)》2021,246(10):1148
This study aimed to evaluate the role of APOE polymorphisms (rs429358 and rs7412) in the risk of age-related macular degeneration in a sample of the Southeastern Brazilian population. Seven hundred and five unrelated individuals were analyzed, 334 with age-related macular degeneration (case group), and 371 without the disease (control group). In the case group, patients were further stratified according to disease phenotypes, divided into dry and wet age-related macular degeneration, and non-advanced and advanced age-related macular degeneration. APOE polymorphisms (rs429358 and rs7412) were evaluated through polymerase chain reaction and direct sequencing. In the comparison of cases vs. controls, none of the associations reached statistical significance, considering the Bonferroni-adjusted P-value, although there was a suggestive protection for the E3/E4 genotype (OR = 0.626; P-value = 0.037) and E4 carriers (OR = 0.6515; P-value = 0.047). Statistically significant protection for both the E3/E4 genotype and E4 carriers was observed in the comparisons: advanced age-related macular degeneration vs. controls (OR = 0.3665, P-value = 0.491 × 10−3 and OR = 0.4031, P-value = 0.814 × 10−3, respectively), advanced age-related macular degeneration vs. non-advanced age-related macular degeneration (OR = 0.2529, P-value = 0.659 × 10−4 and OR = 0.2692, P-value = 0.631 × 10−4, respectively). In the comparison of wet age-related macular degeneration vs. control, protection was statistically significant only for E3/E4 (OR = 0.4052, P-value = 0.001). None of the comparisons demonstrated any significant association for E2 genotypes or E2 carriers in age-related macular degeneration risk in this study. Findings suggest a protective role of the E4 haplotype in the APOE gene in the risk for advanced and wet forms of age-related macular degeneration, in a sample of the Brazilian population. To our knowledge, this is the first Brazilian study to show the association between APOE polymorphisms and age-related macular degeneration. 相似文献
74.
Interactions between transition metal ions and polyphenols can result in complexation, redox or polymerization, but the relative importance of these reactions is unclear. The present paper reports results from the reaction of gallic acid (GA) with Cu(II) using electron paramagnetic resonance (EPR) and UV/visible spectroscopy for various relative concentrations and pH values. Reduction of Cu(II) by GA does not occur under strongly acidic or strongly alkaline conditions. Di- or polymerization reactions between Cu(II) and carboxylate groups of GA dominate the results at acidic pH, whereas mononuclear complexes increase in importance at higher pH and GA concentrations. There was no evidence for any redox reaction between Cu(II) and GA and free radical formation from GA at high pH was shown to be the consequence of auto-oxidation, which was inhibited by Cu(II). Serious questions are thus raised about the existence of the frequently assumed redox reactions between Cu(II) and polyphenols. 相似文献
75.
Ramiro M. Murata Luciana S. Branco-de-Almeida Eliane M. Franco Regiane Yatsuda Marcelo H. dos Santos Severino M. de Alencar 《Biofouling》2013,29(7):865-872
7-Epiclusianone (7-epi), a novel naturally occurring compound isolated from Rheedia brasiliensis, effectively inhibits the synthesis of exopolymers and biofilm formation by Streptococcus mutans. In the present study, the ability of 7-epi, alone or in combination with fluoride (F), to disrupt biofilm development and pathogenicity of S. mutans in vivo was examined using a rodent model of dental caries. Treatment (twice-daily, 60s exposure) with 7-epi, alone or in combination with 125 ppm F, resulted in biofilms with less biomass and fewer insoluble glucans than did those treated with vehicle-control, and they also displayed significant cariostatic effects in vivo (p < 0.05). The combination 7-epi + 125 ppm F was as effective as 250 ppm F (positive-control) in reducing the development of both smooth- and sulcal-caries. No histopathological alterations were observed in the animals after the experimental period. The data show that 7-epiclusianone is a novel and effective antibiofilm/anticaries agent, which may enhance the cariostatic properties of fluoride. 相似文献
76.
Raffaela Cutzu Annalisa Coi Fulvia Rosso Laura Bardi Maurizio Ciani Marilena Budroni Giacomo Zara Severino Zara Ilaria Mannazzu 《World journal of microbiology & biotechnology》2013,29(6):1009-1017
In this work eighteen red yeasts were screened for carotenoids production on glycerol containing medium. Strain C2.5t1 of Rhodotorula glutinis, that showed the highest productivity, was UV mutagenized. Mutant 400A15, that exhibited a 280 % increase in β–carotene production in respect to the parental strain, was selected. A central composite design was applied to 400A15 to optimize carotenoids and biomass productions. Regression analyses of the quadratic polynomial equations obtained (R2 = 0.87 and 0.94, for carotenoids and biomass, respectively) suggest that the models are reliable and significant (P < 0.0001) in the prediction of carotenoids and biomass productions on the basis of the concentrations of crude glycerol, yeast extract and peptone. Accordingly, total carotenoids production achieved (14.07 ± 1.45 mg l?1) under optimized growth conditions was not statistically different from the maximal predicted (14.64 ± 1.57 mg l?1) (P < 0.05), and it was about 100 % higher than that obtained under un-optimized conditions. Therefore mutant 400A15 may represent a biocatalyst of choice for the bioconversion of crude glycerol into value-added metabolites, and a tool for the valorization of this by-product of the biodiesel industry. 相似文献
77.
Cell signaling in NMDA preconditioning and neuroprotection in convulsions induced by quinolinic acid
The search for novel, less invasive therapeutic strategies to treat neurodegenerative diseases has stimulated scientists to investigate the mechanisms involved in preconditioning. Preconditioning has been report to occur in many organs and tissues. In the brain, the modulation of glutamatergic transmission is an important and promising target to the use of effective neuroprotective agents. The glutamatergic excitotoxicity is a factor common to neurodegenerative diseases and acute events such as cerebral ischemia, traumatic brain injury and epilepsy. In this review we focus on the neuroprotection and preconditioning by chemical agents. Specially, chemical preconditioning models using N-methyl-d-aspartate (NMDA) pre-treatment, which has demonstrated to lead to neuroprotection against seizures and damage to neuronal tissue induced by quinolinic acid (QA). Here we attempted to gather important results obtained in the study of cellular and molecular mechanisms involved in NMDA preconditioning and neuroprotection. 相似文献
78.
Using a space-for-time substitution approach, we investigated the effects of a typhoon on the vegetation and soil development trajectories of monospecific stands of Rhizophora mucronata mangroves of different ages (6-, 8- 10-, 11-, 12-, 17-, 18- and 50-year stands). The vegetation and soil parameters were compared to a reference system comprised of mature, natural mangrove stands. Pre-typhoon measures of vegetation and soil parameters were compared with 1-mo, 7-mo and 9-mo post-typhoon. Prior to the occurrence of the typhoon, there were clear patterns of vegetation and soil development with age of the stands. The development trajectory was however interrupted by the occurrence of the typhoon. Severe damage was more apparent in older mangrove stands (11- and 18- year stands) with very low to no damage in the younger stands. The typhoon-impacted sites experienced a number of changes, including: complete defoliation; reduced living tree densities of 61–69 %; decreased above-ground biomass of 70–79 %; increased soil nutrient levels of 40–60 %; more waterlogged soils by at least 113 % and increased soil temperature of 8–10 °C. Cumulative tree mortality, compounded by the lack of seedling recruits and unfavourable soil conditions may limit long-term recovery of the typhoon-impacted stands. 相似文献
79.
Clelia Muccio Vincenzo Guida Amalia Di Petrillo Valeria Severino Antimo Di Maro 《The protein journal》2012,31(8):667-673
A novel malate dehydrogenase (MDH; EC 3.1.1.1.37), hereafter MDHCs, from Ceratonia siliqua seeds, commonly known as Carob tree, was purified by using ammonium sulphate precipitation, ion exchange chromatography on SteamLine SP and gel-filtration. The molecular mass of the native protein, obtained by analytical gel-filtration, was about 65?kDa, whereas, by using SDS-PAGE analysis, with and without reducing agent, was 34?kDa. The specific activity of purified MDHCs (0.25?mg/100?g seeds) was estimated to be 188 U/mg. The optimum activity of the enzyme is at pH 8.5, showing a decrease in the presence of Ca2+, Mg2+ and NaCl. The N-terminal sequence of the first 20 amino acids of MDHCs revealed 95?% identity with malate dehydrogenase from Medicago sativa L. Finally, the enzymatic activity of MDHCs was preserved even after absorption onto a PVDF membrane. To our knowledge, this is the first contribution to the characterization of an enzyme from Carob tree sources. 相似文献
80.
Alberto Migliore Umberto Massafra Emanuele Bizzi Francesca Vacca Severino Martin-Martin Mauro Granata Andrea Alimonti Sandro Tormenta 《Arthritis research & therapy》2009,11(6):R183