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1.
Heteromazocraes mamaevi n. sp. is described from a cyprinid, Securicula gora (Ham.) from the Lucknow district, India. It is characterised by well-developed cephalic glands, the shape of the genital spines, the structure of the egg and the shape of the clamp sclerites. This is the first record of the genus Heteromazocraes Mamaev, 1981 from a cyprinid fish.  相似文献   
2.
Sn (tin)-mesoporphyrin (Sn-protoporphyrin in which the vinyl groups at C2 and C4 have been reduced to ethyl groups) when incubated with rat splenic microsomal heme oxygenase proved to be a potent competitive inhibitor of enzyme activity in vitro, with a Ki of 0.014 microM. Sn-mesoporphyrin (1 mumol/kg body wt) also inhibited hepatic, renal, and splenic heme oxygenase activity in vivo in adult animals for extended periods of time. Sn-mesoporphyrin (1 mumol/kg body wt) prevented the transient increase in serum bilirubin 24 h after birth in the rat neonate and substantially reduced the levels of serum bilirubin in ALA (delta-aminolevulinic acid) induced hyperbilirubinemia in the 7-day-old suckling neonate. Tissue heme oxygenase activity was decreased in both animal models of hyperbilirubinemia. Sn-mesoporphyrin administration led to a prolonged increase in the heme saturation of hepatic tryptophan pyrrolase indicating an increase in the "heme pool" related to tryptophan pyrrolase and the compound also suppressed chemically induced hepatic porphyria. The administration of Sn-mesoporphyrin to bile duct-cannulated rats was followed by a prompt and sustained decrease in bilirubin output in bile. In addition the excretion of heme in bile was enhanced in these animals. These studies indicate that Sn-mesoporphyrin, like Sn-protoporphyrin, decreases serum bilirubin by inhibiting the production of bilirubin in vivo and its mode of action is through a sustained competitive inhibition of heme oxygenase. However, when a direct comparison of Sn-protoporphyrin and Sn-mesoporphyrin was made, these studies clearly established that the reduction of the C2 and C4 vinyl groups of the porphyrin macrocycle to ethyl groups increases the effectiveness of the Sn-mesoporphyrin derivative 10-fold or more as compared with Sn-protoporphyrin in inhibiting heme catabolism in the animal model systems examined. Thus alterations in the side chain substituents as well as of the central metal atom can influence in a significant manner the potency of the resultant synthetic heme analog as an agent capable of inhibiting heme degradation in vivo.  相似文献   
3.
The genomic clone named Bp10 contains a member of a small pollen-specific gene family of B. napus. The expression of the Bp10 gene family is maximal in early binucleate microspores and declines considerably in mature trinucleate pollen. Homologues of the Bp10 genes are expressed in the pollen of other plant species. The pollen-specific expression of the gene contained in the genomic clone was confirmed in tobacco plants transformed with a chimeric Bp10 promoter/GUS construct. A promoter fragment of 396 bp is sufficient to direct a strong and correct spatial and temporal expression in transgenic plants. The Bp10 gene family codes for proteins of 62 kDa showing approximately 30% sequence identify to cucumber and pumpkin ascorbate oxidases (AAOs). However, the AAO active centres are not conserved in the Bp10 products, suggesting an evolutionary relationship but a different enzymatic activity for these proteins. Expression of a recombinant Bp10 protein in E. coli inhibits bacterial growth on minimal medium, suggesting the production of an enzymatically active polypeptide in bacteria. No AAO activity could be correlated with the expression of the recombinant protein. Moreover, substances affecting AAO activity do not appear to influence the inhibitory activity of the protein produced in bacteria. However, as indicated by the rescue of bacterial growth in the presence of sodium bicarbonate or gaseous CO2, the Bp10 protein activity could be modulated by CO2 levels.  相似文献   
4.
5.
An invertebrate alpha-ketoglutarate-dependent aspartyl/asparaginyl beta-hydroxylase, which posttranslationally hydroxylates specific aspartyl or asparaginyl residues within epidermal growth factor-like modules, was identified, partially purified and characterized. Preparations derived from two insect cell lines catalyzed the hydroxylation of the expected asparaginyl residue within a synthetic epidermal growth factor-like module. This activity was found to be similar to that of the purified mammalian aspartyl/asparaginyl beta-hydroxylase with respect to cofactor requirements, stereochemistry and substrate sequence specificity. Furthermore, recombinant human C1r, expressed in an insect cell-derived baculovirus expression system, was also found to be hydroxylated at the expected asparaginyl residue. Thus, these results establish the potential for invertebrate aspartyl/asparaginyl hydroxylation. Since several invertebrate proteins known to be required for proper embryonic development contain a putative consensus sequence that may be required for hydroxylation, the studies presented here provide the basis for further investigations concerned with identifying hydroxylated invertebrate proteins and determining their physiologic function.  相似文献   
6.
Caloric restriction (CR) has positive effects on health and longevity. CR in mammals implements time‐restricted (TR) feeding, a short period of feeding followed by prolonged fasting. Periodic fasting, in the form of TR or mealtime, improves metabolism without reduction in caloric intake. In order to understand the relative contribution of reduced food intake and periodic fasting to the health benefits of CR, we compared physiological and metabolic changes induced by CR and TR (without reduced food intake) in mice. CR significantly reduced blood glucose and insulin around the clock, improved glucose tolerance, and increased insulin sensitivity (IS). TR reduced blood insulin and increased insulin sensitivity, but in contrast to CR, TR did not improve glucose homeostasis. Liver expression of circadian clock genes was affected by both diets while the mRNA expression of glucose metabolism genes was significantly induced by CR, and not by TR, which is in agreement with the minor effect of TR on glucose metabolism. Thus, periodic fasting contributes to some metabolic benefits of CR, but TR is metabolically different from CR. This difference might contribute to differential effects of CR and TR on longevity.  相似文献   
7.
Abstract

The study recommends the Artemisia nilagirica (Clarke) Pamp. essential oil (ANEO) as plant-based shelf-life enhancer of millets against fungal, aflatoxin B1 (AFB1) contamination and lipid peroxidation with favourable safety profile. Chemical characterisation of ANEO through GC-MS, recorded 1,5-heptadiene-4-one,3,3,6-trimethyl (32.72%)as the main compound, followed by Artemisia alcohol (13.40%), alpha lonone (4.55%), benzene, methyl (1-methylethyl) (2.97%) and 1-cyclohexene-1-carboxaldehyde,4-(1-methylethyenyl) (2.23%). The mycoflora analysis of millet samples showed Aspergillus flavus strain[LHP(R)-5] as the most AFB1 secreting strain. The ANEO inhibited growth and AFB1 production by the toxigenic strain at 1.4 and 1.0?µL?mL?1, respectively, and also possess broad fungitoxic spectrum. The decrement in membrane ergosterol content, enhanced leakage of cellular Ca2+, K+ and Mg2+ ions along with SEM and TEM study of ANEO-treated cell denotes plasma membrane as antifungal site of action. The ANEO also showed strong antioxidant activity as determined by DPPH? and ABTS?+ assays having IC50 value 2.51 and 1.07?µL?mL?1, respectively. More than 70.78% protection of Ragi samples from fungal contamination was observed during in situ trial. The ANEO showed favourable safety profile with high LD50 value (7528.10?µL?kg?1) for male mice and also exhibited non-phytotoxicity for Ragi seeds germination.  相似文献   
8.

The present study examined the anti-biofilm efficacy of two short-chain antimicrobial peptides (AMPs), namely, indolicidin and cecropin A (1-7)-melittin (CAMA) against biofilm-forming multidrug-resistant enteroaggregative Escherichia coli (MDR-EAEC) isolates. The typical EAEC isolates re-validated by PCR and confirmed using HEp-2 cell adherence assay was subjected to antibiotic susceptibility testing to confirm its MDR status. The biofilm-forming ability of MDR-EAEC isolates was assessed by Congo red binding, microtitre plate assays and hydrophobicity index; broth microdilution technique was employed to determine minimum inhibitory concentrations (MICs) and minimum biofilm eradication concentrations (MBECs). The obtained MIC and MBEC values for both AMPs were evaluated alone and in combination against MDR-EAEC biofilms using crystal violet (CV) staining and confocal microscopy-based live/dead cell quantification methods. All the three MDR-EAEC strains revealed weak to strong biofilm-forming ability and were found to be electron-donating and weakly electron-accepting (hydrophobicity index). Also, highly significant (P < 0.001) time-dependent hydrodynamic growth of the three MDR-EAEC strains was observed at 48 h of incubation in Dulbecco’s modified Eagle’s medium (DMEM) containing 0.45% D-glucose. AMPs and their combination were able to inhibit the initial biofilm formation at 24 h and 48 h as evidenced by CV staining and confocal quantification. Further, the application of AMPs (individually and combination) against the preformed MDR-EAEC biofilms resulted in highly significant eradication (P < 0.001) at 24 h post treatment. However, significant differences were not observed between AMP treatments (individually or in combination). The AMPs seem to be an effective candidates for further investigations such as safety, stability and appropriate biofilm-forming MDR-EAEC animal models.

  相似文献   
9.
Key message

Genome wide association studies allowed prediction of 17 candidate genes for association with nitrogen use efficiency. Novel information obtained may provide better understanding of genomic controls underlying germplasm variations for this trait in Indian mustard.

Abstract

Nitrogen use efficiency (NUE) of Indian mustard (Brassica juncea (L.) Czern & Coss.) is low and most breeding efforts to combine NUE with crop performance have not succeeded. Underlying genetics also remain unexplored. We tested 92 SNP-genotyped inbred lines for yield component traits, N uptake efficiency (NUPEFF), nitrogen utilization efficiency (NUTEFF), nitrogen harvest index (NHI) and NUE for two years at two nitrogen doses (No without added N and N100 added @100 kg/ha). Genotypes IC-2489-88, M-633, MCP-632, HUJM 1080, GR-325 and DJ-65 recorded high NUE at low N. These also showed improved crop performance under high N. One determinate mustard genotype DJ-113 DT-3 revealed maximum NUTEFF. Genome wide association studies (GWAS) facilitated recognition of 17 quantitative trait loci (QTLs). Environment specificity was high. B-genome chromosomes (B02, B03, B05, B07 and B08) harbored many useful loci. We also used regional association mapping (RAM) to supplement results from GWAS. Annotation of the genomic regions around peak SNPs helped to predict several gene candidates for root architecture, N uptake, assimilation and remobilization. CAT9 (At1g05940) was consistently envisaged for both NUE and NUPEFF. Major N transporter genes, NRT1.8 and NRT3.1 were predicted for explaining variation for NUTEFF and NUPEFF, respectively. Most significant amino acid transporter gene, AAP1 appeared associated with NUE under limited N conditions. All these candidates were predicted in the regions of high linkage disequilibrium. Sequence information of the predicted candidate genes will permit development of molecular markers to aid breeding for high NUE.

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10.

In the recent past, huge emphasis has been given to the epigenetic alterations of the genes responsible for the cause of neurological disorders. Earlier, the scientists believed somatic changes and modifications in the genetic makeup of DNA to be the main cause of the neurodegenerative diseases. With the increase in understanding of the neural network and associated diseases, it was observed that alterations in the gene expression were not always originated by the change in the genetic sequence. For this reason, extensive research has been conducted to understand the role of epigenetics in the pathophysiology of several neurological disorders including Alzheimer’s disease, Parkinson’s disease and, Huntington’s disease. In a healthy person, the epigenetic modifications play a crucial role in maintaining the homeostasis of a cell by either up-regulating or down-regulating the genes. Therefore, improved understanding of these modifications may provide better insight about the diseases and may serve as potential therapeutic targets for their treatment. The present review describes various epigenetic modifications involved in the pathology of Parkinson’s Disease (PD) backed by multiple researches carried out to study the gene expression regulation related to the epigenetic alterations. Additionally, we will briefly go through the current scenario about the various treatment therapies including small molecules and multiple phytochemicals potent enough to reverse these alterations and the future directions for a better management of PD.

  相似文献   
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