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131.
Silvia P. Trajtemberg Nancy M. Apóstolo Graciela Fernández 《In vitro cellular & developmental biology. Plant》2006,42(6):534-537
Summary
Cynara cardunculus var. cardunculus L., also known as cardoon, is a perennial weed naturalized in the Pampas region of Argentina. A quantification of cynarine
and chlorogenic acid of callus and leaves from cardoon was performed by means of micellar electrokinetic capillary chromatography,
showing that the content of cynarine is higher in calluses than in vivo leaves. The scavenging effect of the callus extract, determined by the thiobarbituric acid method, demonstrated its significant
antioxidant capacity. The obtained results revealed that in vitro tissue culture is an excellent tool for producing cynarine for therapeutical purposes. 相似文献
132.
Folate is a B-group vitamin that cannot be synthesized by humans and must be obtained exogenously. Although some species of lactic acid bacteria (LAB) can produce folates, little is known about the production of this vitamin by yogurt starter cultures. Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus strains were isolated from artisanal Argentinean yogurts and were grown in folate-free culture medium (FACM) and nonfat milk after which intracellular and extracellular folate production were evaluated. From the initial 92 isolated LAB strains, 4 L. delbrueckii subsp. bulgaricus and 32 S. thermophilus were able to grow in the absence of folate. Lactobacillus delbrueckii subsp. bulgaricus CRL 863 and S.?thermophilus CRL 415 and CRL 803 produced the highest extracellular folate levels (from 22.3 to 135?μg/L) in FACM. In nonfat milk, these strains were able to increase the initial folate concentrations by almost 190%. This is the first report where native strains of L. delbrueckii subsp. bulgaricus were shown to produce natural folate. The LAB strains identified in this study could be used in developing novel fermented products bio-enriched in natural folates that could in turn be used as an alternative to fortification with the controversial synthetic chemical folic acid. 相似文献
133.
Lessard CJ Adrianto I Ice JA Wiley GB Kelly JA Glenn SB Adler AJ Li H Rasmussen A Williams AH Ziegler J Comeau ME Marion M Wakeland BE Liang C Ramos PS Grundahl KM Gallant CJ Alarcón-Riquelme ME Alarcón GS Anaya JM Bae SC Boackle SA Brown EE Chang DM Cho SK Criswell LA Edberg JC Freedman BI Gilkeson GS Jacob CO James JA Kamen DL Kimberly RP Kim JH Martin J Merrill JT Niewold TB Park SY Petri MA Pons-Estel BA Ramsey-Goldman R Reveille JD Scofield RH Song YW Stevens AM Tsao BP Vila LM Vyse TJ 《American journal of human genetics》2012,90(4):648-660
Systemic lupus erythematosus (SLE) is a chronic heterogeneous autoimmune disorder characterized by the loss of tolerance to self-antigens and dysregulated interferon responses. The etiology of SLE is complex, involving both heritable and environmental factors. Candidate-gene studies and genome-wide association (GWA) scans have been successful in identifying new loci that contribute to disease susceptibility; however, much of the heritable risk has yet to be identified. In this study, we sought to replicate 1,580 variants showing suggestive association with SLE in a previously published GWA scan of European Americans; we tested a multiethnic population consisting of 7,998 SLE cases and 7,492 controls of European, African American, Asian, Hispanic, Gullah, and Amerindian ancestry to find association with the disease. Several genes relevant to immunological pathways showed association with SLE. Three loci exceeded the genome-wide significance threshold: interferon regulatory factor 8 (IRF8; rs11644034; pmeta-Euro = 2.08 × 10−10), transmembrane protein 39A (TMEM39A; rs1132200; pmeta-all = 8.62 × 10−9), and 17q21 (rs1453560; pmeta-all = 3.48 × 10−10) between IKAROS family of zinc finger 3 (AIOLOS; IKZF3) and zona pellucida binding protein 2 (ZPBP2). Fine mapping, resequencing, imputation, and haplotype analysis of IRF8 indicated that three independent effects tagged by rs8046526, rs450443, and rs4843869, respectively, were required for risk in individuals of European ancestry. Eleven additional replicated effects (5 × 10−8 < pmeta-Euro < 9.99 × 10−5) were observed with CFHR1, CADM2, LOC730109/IL12A, LPP, LOC63920, SLU7, ADAMTSL1, C10orf64, OR8D4, FAM19A2, and STXBP6. The results of this study increase the number of confirmed SLE risk loci and identify others warranting further investigation. 相似文献
134.
Ana Varea Agustina Malpeli Liliana Disalvo María Apezteguía Mariana Falivene Guillermina Ferrari Silvia Pereyras Estéban Carmuega Graciela Etchegoyen María Vojkovic Horacio F. González 《Biological trace element research》2012,150(1-3):103-108
This study was conducted to evaluate the impact of a food aid program (Plan Más Vida, PMV) on the micronutrient nutritional condition of lactating mothers 1?year after its implementation. The food program provided supplementary diets (wheat- and maize-fortified flour, rice or sugar, and fortified soup) to low-income families from the province of Buenos Aires, Argentina. A prospective, non-experimental study was carried out to evaluate the micronutrient nutritional status of lactating mothers (n?=?178 at baseline and n?=?151 after 1?year). Biochemical tests (hemoglobin, ferritin, zinc, vitamin A, and folic acid), anthropometric assessments (weight and height) and dietary surveys (24-h recall) were performed. We found no significant changes in anthropometric values 1?year after the intervention. The risk for vitamin A (retinol 20?C30???g/dl) and folate deficiency significantly decreased 1?year after PMV implementation (56.3 vs. 29.9 and 50.3 vs. 3.4?%, respectively; p?<?0.001). Anemia was seen in 25.8?% of lactating mothers at baseline, without statistically significant differences 1?year after (p?=?0.439). The nutritional data obtained after assessing the early impact of PMV actions may be useful to provincial health authorities to perform periodic evaluations in the future. 相似文献
135.
Rodríguez C Rimaux T Fornaguera MJ Vrancken G de Valdez GF De Vuyst L Mozzi F 《Applied microbiology and biotechnology》2012,93(6):2519-2527
Certain lactic acid bacteria, especially heterofermentative strains, are capable to produce mannitol under adequate culture
conditions. In this study, mannitol production by Lactobacillus reuteri CRL 1101 and Lactobacillus fermentum CRL 573 in modified MRS medium containing a mixture of fructose and glucose in a 6.5:1.0 ratio was investigated during batch
fermentations with free pH and constant pH 6.0 and 5.0. Mannitol production and yields were higher under constant pH conditions
compared with fermentations with free pH, the increase being more pronounced in the case of the L. fermentum strain. Maximum mannitol production and yields from fructose for L. reuteri CRL 1101 (122 mM and 75.7 mol%, respectively) and L. fermentum CRL 573 (312 mM and 93.5 mol%, respectively) were found at pH 5.0. Interestingly, depending on the pH conditions, fructose
was used only as an alternative external electron acceptor or as both electron acceptor and energy source in the case of the
L. reuteri strain. In contrast, L. fermentum CRL 573 used fructose both as electron acceptor and carbon source simultaneously, independently of the pH value, which strongly
affected mannitol production by this strain. Studies on the metabolism of these relevant mannitol-producing lactobacilli provide
important knowledge to either produce mannitol to be used as food additive or to produce it in situ during fermented food
production. 相似文献
136.
Paulo E. C. Peixoto Danilo Muniz Woodruff W. Benson 《Ethology : formerly Zeitschrift fur Tierpsychologie》2012,118(3):311-319
Among polygynous species, males often compete for the possession of mating sites to increase their reproductive success. Weaker individuals frequently adopt alternative non‐territorial mate‐locating tactics, but the adoption of alternative territorial tactics may also occur. Although alternative tactics with territory defence are less common in arthropods, factors that drive its adoption may provide information to understand the organization of different territorial mating systems in the group. Here we investigate the adoption of resource‐based territoriality as an alternative to a non‐resource‐based one by males of the butterfly Paryphthimoides phronius. Male P. phronius commonly defend sunny clearings lacking feeding resources in the forest edge (non‐resource‐based territoriality). However, after experimentally offering fermenting fruit in previously undefended sites, we showed that males also adopt a resource defence tactic. Males in territories with fermenting fruits apparently feed on this resource when they are not defending the territory. However, males in sites without resources did not migrate to territories with resources when given the opportunity. To our knowledge, this is the first experimental investigation to show a non‐resource‐ and an alternative resource‐based mate‐locating tactic in a butterfly. We suggest that this behavioural flexibility may represent an important step to understand the ecological factors responsible for the organization and evolution of different territorial mating systems in insects. 相似文献
137.
AT Paulino AG Pereira AR Fajardo K Erickson MJ Kipper EC Muniz LA Belfiore EB Tambourgi 《Carbohydrate polymers》2012,90(3):1216-1225
The preparation and characterization of natural polymer-based hydrogels that contain 50-nm diameter magnetite (i.e., FeO:Fe(2)O(3)) nanoparticles are described herein. Fourier-transform infrared spectroscopy (FTIR) analysis confirmed the efficiency of the polysaccharide-modifying process. Thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and compressive moduli demostrate that the presence of magnetite improves thermal and mechanical resistance. Transient diffusion of water in magnetic hydrogels was analyzed via boundary layer mass transfer across an expaning interface, and the degree of swelling of these polysaccharide hydrogels decreases in the presence of magnetite, with no variation in the binary diffusion mechanism. The absence of hysteresis loops and coercivity observed via magnetometry suggests that magnetic hydrogels are useful for remote-controlled drug release, as demonstrated by magnetic-field-induced release of curcumin. Experiments reveal that magnetic hydrogels with greater magnetic susceptibility have the potential to release larger concentrations of drugs from the hydrogel network. 相似文献
138.
Hebert EM Saavedra L Taranto MP Mozzi F Magni C Nader ME Font de Valdez G Sesma F Vignolo G Raya RR 《Journal of bacteriology》2012,194(2):538-539
Lactobacillus curvatus is one of the most prevalent lactic acid bacteria found in fermented meat products. Here, we present the draft genome sequence of Lactobacillus curvatus CRL705, a bacteriocin producer strain isolated from an Argentinean artisanal fermented sausage, which consists of 1,833,251 bp (GC content, 41.9%) and two circular plasmids of 12,342 bp (pRC12; GC, 43.9%) and 18,664 bp (pRC18; GC, 34.4%). 相似文献
139.
Luckwu de Lucena BT Silva GG Manoel Dos Santos B Dias GM Amaral GR Moreira AP de Morais Júnior MA Dutilh BE Edwards RA Balbino V Thompson CC Thompson FL 《Journal of bacteriology》2012,194(11):3018
We report on the genome sequences of Lactobacillus vini type strain LMG 23202(T) (DSM 20605) (isolated from fermenting grape musts in Spain) and the industrial strain L. vini JP7.8.9 (isolated from a bioethanol plant in northeast Brazil). All contigs were assembled using gsAssembler, and genes were predicted and annotated using Rapid Annotation using Subsystem Technology (RAST). The identified genome sequence of LMG 23202(T) had 2.201.333 bp, 37.6% G+C, and 1,833 genes, whereas the identified genome sequence of JP7.8.9 had 2.301.037 bp, 37.8% G+C, and 1,739 genes. The gene repertoire of the species L. vini offers promising opportunities for biotechnological applications. 相似文献
140.
Despite their similarities to bone marrow precursor cells (PC), human umbilical cord blood (HUCB) PCs are more immature and, thus, they exhibit greater plasticity. This plasticity is evident by their ability to proliferate and spontaneously differentiate into almost any cell type, depending on their environment. Moreover, HUCB-PCs yield an accessible cell population that can be grown in culture and differentiated into glial, neuronal and other cell phenotypes. HUCB-PCs offer many potential therapeutic benefits, particularly in the area of neural replacement. We sought to induce the differentiation of HUCB-PCs into glial cells, known as aldynoglia. These cells can promote neuronal regeneration after lesion and they can be transplanted into areas affected by several pathologies, which represents an important therapeutic strategy to treat central nervous system damage. To induce differentiation to the aldynoglia phenotype, HUCB-PCs were exposed to different culture media. Mononuclear cells from HUCB were isolated and purified by identification of CD34 and CD133 antigens, and after 12 days in culture, differentiation of CD34+ HUCB-PCs to an aldynoglia phenotypic, but not that of CD133+ cells, was induced in ensheathing cell (EC)-conditioned medium. Thus, we demonstrate that the differentiation of HUCB-PCs into aldynoglia cells in EC-conditioned medium can provide a new source of aldynoglial cells for use in transplants to treat injuries or neurodegenerative diseases. 相似文献