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981.
982.
983.
Tambaqui (Colossoma macropomum) is a fish species from the Amazon and Orinoco Rivers, with favorable characteristics to the cultivation system and great market acceptance in South America. However, the construction of a genetic map for the genetic improvement of this species is limited by the low number of molecular markers currently described. Thus, this study aimed to validate gene-associated and anonymous (non-genic) microsatellites obtained by next generation sequencing (RNA-seq and whole genome shotgun—WGS, respectively), for future construction of a genetic map and search for quantitative trait loci (QTL) in this species. In the RNA-seq data, the observed and expected heterozygosity (Ho and He) ranged from 0.09 to 0.73, and 0.09 to 0.85, respectively. In the WGS data, Ho and He ranged from 0.33 to 0.95, and 0.28 to 0.92, respectively. In general, the evaluation of 200 markers resulted in 45 polymorphic loci, of which 14 were gene-associated (RNA-Seq) and 31 were anonymous (WGS). Moreover, some markers were related to genes of the immune system, biological regulation/control and biogenesis. This study contributes to increase the number of molecular markers available for genetic studies in C. macropomum, which will allow the development of breeding programs assisted by molecular markers.  相似文献   
984.
In this study, we synthesized 18F-ASu-BF3, a close boramino acid analog of 5-[18F]fluoro-aminosuberic acid (18F-ASu), via 18F-19F isotope exchange reaction and evaluated its potential for imaging with positron emission tomography (PET). 18F-ASu-BF3 was stable in mouse plasma and taken up into PC3 prostate cancer cells via the system xC? amino acid transporter. The continuous use of isoflurane for anesthesia during dynamic imaging acquisition slowed down the excretion of 18F-ASu-BF3 and enabled visualization of PC3 tumor xenografts in mice. In contrast, no tumor visualization was observed from static images of 18F-BF3-ASu due to its rapid renal excretion mediated in part by the organic anion transporter. Our data indicate that the pharmacokinetics of amino acids could be altered after being converted into their boramino acid analogs. Therefore, care should be taken when using the boramino acid strategy to design and prepare 18F-labeled tracers for imaging amino acid transporters/receptors with PET.  相似文献   
985.
Fermented milks are a source of bioactive peptides and may be considered as functional foods. Among these, sheep’s milk fermented with kefir has not been widely studied and its most relevant properties need to be more thoroughly characterized. This research study is set out to investigate and evaluate the antioxidant and antimicrobial properties of peptides from fermented sheep’s milk in Brazil when produced by using kefir. For this, the chemical and microbiological composition of the sheep’s milk before and after the fermentation was evaluated. The changes in the fermented milk and the peptides extracted before the fermentation and in the fermented milk during its shelf life were verified. The antimicrobial and antioxidant activities of the peptides from the fermented milk were evaluated and identified according to the literature. The physicochemical properties and mineral profile of the fermented milk were like those of fresh milk. The peptide extract presented antimicrobial activity and it was detected that 13 of the 46 peptides were able to inhibit the growth of pathogenic microorganisms. A high antioxidant activity was observed in the peptides extracted from fermented milk (3.125 mg/mL) on the 28th day of storage. Two fractions displayed efficient radical scavenging properties by DPPH and ABTS methods. At least 11 peptides distributed in the different fractions were identified by tandem mass spectrometry. This sheep’s milk fermented by Brazilian kefir grains, which has antioxidant and antimicrobial activities and probiotic microorganisms, is a good candidate for further investigation as a source for bioactive peptides. The fermentation process was thus a means by which to produce potential bioactive peptides.  相似文献   
986.
The stink bug complex includes some of the most important soybean pests worldwide. Among these insects, Piezodorus guildinii (Westwood) (Hemiptera: Pentatomidae) is known for the severe damage it can cause and for its resistance to chemical management. Host plant resistance is considered as an important tool in the management of these pests. In particular, plant flavonoids, such as genistein and rutin, have been identified as compounds that might negatively affect the development of some pests; however, the effects of these compounds on some stink bug species are still unclear. We tested the resistance of soybean genotypes by evaluating the growth and survival of P. guildinii under laboratory conditions. In addition, the amounts of genistein and rutin were quantified in both infested and non-infested genotypes. The PI 274453, PI 274454, PI 227687, PI 229358, ‘IAC 100′, and ‘IAC 19′ genotypes showed antibiosis to P. guildinii. The genistein and rutin flavonoids appear to play a role in the resistance of these genotypes against P. guildinii; specifically, PI 274453, PI 274454, and ‘IAC 100′ showed induced resistance against the insect. Other defence mechanisms or flavonoids might be involved in resistance in the L1-1-01 and PI 171451 genotypes. These results help us better understand the role of flavonoids in plant defence mechanisms and might prove useful in breeding programmes aimed at developing resistant soybean plants.  相似文献   
987.
In the present study, ethanolic extracts of ten cyanobacterial strains cultivated under different nitrogen conditions were assessed for the phenolic content and antioxidant activity. The amount of detected phenolic compounds ranged from 14.86 to 701.69 μg g?1 dry weight (dw) and HPLC-MS/MS analysis revealed gallic acid, chlorogenic acid, quinic acid, catechin, epicatechin, kaempferol, rutin and apiin. Only catechin, among the detected phenolics, was present in all the tested strains, while quinic acid was the most dominant compound in all the tested Nostoc strains. The results also indicated the possibility of increasing the phenolic content in cyanobacterial biomass by manipulating nitrogen conditions, such as in the case of quinic acid in Nostoc 2S7B from 70.83 to 594.43 μg g?1 dw. The highest radical scavenging activity in DPPH assay expressed Nostoc LC1B with IC50 value of 0.04?±?0.01 mg mL?1, while Nostoc 2S3B with IC50 =?9.47?±?3.61 mg mL?1 was the least potent. Furthermore, the reducing power determined by FRAP assay ranged from 8.36?±?0.08 to 21.01?±?1.66 mg AAE g?1, and it was significantly different among the tested genera. The Arthrospira strains exhibited the highest activity, which in the case of Arthrospira S1 was approximately twofold higher in comparison to those in nitrogen-fixing strains. In addition to this, statistical analysis has indicated that detected phenolics were not major contributor to antioxidant capacities of tested cyanobacteria. However, this study highlights cyanobacteria of the genera Nostoc, Anabaena, and Arthrospira as producers of antioxidants and phenolics with pharmacological and health-beneficial effects, i.e., quinic acid and catechin in particular.  相似文献   
988.
989.
We report a 38-year-old woman presenting with febrile neutropenia, acute myeloid leukemia (AML) and invasive mucormycosis. Bone marrow aspirate was characteristic of AML minimally differentiated (WHO classification 2008). Flow cytometric immunophenotyping analysis showed blasts positive for CD7, CD33, CD34, CD71, CD117, HLA-DR, MPO, and TdT, with normal karyotype (46, XX), and the absence of the FLT3-ITD and NPM1 mutations. The patient’s management included chemotherapy with cytarabine and idarubicin, and treatment with liposomal amphotericin B, deferasirox, hyperbaric oxygen therapy, and antibiotics. Nowadays, she is in complete hematological remission, and CT images of control are normal. Invasive mucormycosis is an uncommon and severe condition, which involves diagnosis and treatment challenges. Clinical features and predisposing factors should be highlighted in order to enhance the suspicion index, contributing to early diagnosis and disease control. Our aim is to report classical features of this uncommon condition and to emphasize usual management challenges.  相似文献   
990.
Peptidomic analysis of norepinephrine-stimulated skin secretions of the tetraploid clawed frog Xenopus laevis (Pipidae) led to the identification of 10 peptides with the ability to stimulate the release of insulin from the rat BRIN-BD11 clonal β cell line. These peptides were purified to near homogeneity and structural characterization showed that they belong to the magainin (2 peptides), peptide glycine-leucine-amide (PGLa) (1 peptide), xenopsin precursor fragment (1 peptide), and caerulein precursor fragment (CPF) (6 peptides) families. CPF-1, CPF-3, CPF-5 and CPF-6 were the most potent producing a significant (P < 0.05) increase in the rate of insulin release at concentration of 0.03 nM. CPF-7 (GFGSFLGKALKAALKIGANALGGAPQQ) produced the maximum stimulation of insulin release (571 ± 30% of basal rate at 3 μM). In addition, CPF-SE1 (GFLGPLLKLGLKGVAKVIPHLIPSRQQ), previously isolated from skin secretions of the tetraploid frog Silurana epitropicalis, produced a significant (P < 0.05) increase in the rate of insulin release at 0.03 nM with a 514 ± 13% increase over basal rate at 3 μM. No CPF peptide stimulated release of the cytosolic enzyme, lactate dehydrogenase from BRIN-BD11 cells at concentrations up to 3 μM indicating that the integrity of the plasma membrane had been preserved. The mechanism of action of the CPF peptides involves, at least in part, membrane depolarization and an increase in intracellular Ca2+ concentration. The CPF peptides show potential for development into agents for the treatment of Type 2 diabetes.  相似文献   
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