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201.
Snakebite envenomation is a serious medical problem in many tropical developing countries and was considered by WHO as a neglected tropical disease. Antivenom (AV), the rational and most effective treatment modality, is either unaffordable and/or unavailable in many affected countries. Moreover, each AV is specific to only one (monospecific) or a few (polyspecific) snake venoms. This demands that each country to prepare AV against its local snake venoms, which is often not feasible. Preparation of a ‘pan-specific’ AV against many snakes over a wide geographical area in some countries/regions has not been possible. If a ‘pan-specific’ AV effective against a variety of snakes from many countries could be prepared, it could be produced economically in large volume for use in many countries and save many lives. The aim of this study was to produce a pan-specific antiserum effective against major medically important elapids in Asia. The strategy was to use toxin fractions (TFs) of the venoms in place of crude venoms in order to reduce the number of antigens the horses were exposed to. This enabled inclusion of a greater variety of elapid venoms in the immunogen mix, thus exposing the horse immune system to a diverse repertoire of toxin epitopes, and gave rise to antiserum with wide paraspecificity against elapid venoms. Twelve venom samples from six medically important elapid snakes (4 Naja spp. and 2 Bungarus spp.) were collected from 12 regions/countries in Asia. Nine of these 12 venoms were ultra-filtered to remove high molecular weight, non-toxic and highly immunogenic proteins. The remaining 3 venoms were not ultra-filtered due to limited amounts available. The 9 toxin fractions (TFs) together with the 3 crude venoms were emulsified in complete Freund’s adjuvant and used to immunize 3 horses using a low dose, low volume, multisite immunization protocol. The horse antisera were assayed by ELISA and by in vivo lethality neutralization in mice. The findings were: a) The 9 TFs were shown to contain all of the venom toxins but were devoid of high MW proteins. When these TFs, together with the 3 crude venoms, were used as the immunogen, satisfactory ELISA antibody titers against homologous/heterologous venoms were obtained. b) The horse antiserum immunologically reacted with and neutralized the lethal effects of both the homologous and the 16 heterologous Asian/African elapid venoms tested. Thus, the use of TFs in place of crude venoms and the inclusion of a variety of elapid venoms in the immunogen mix resulted in antiserum with wide paraspecificity against elapid venoms from distant geographic areas. The antivenom prepared from this antiserum would be expected to be pan-specific and effective in treating envenomations by most elapids in many Asian countries. Due to economies of scale, the antivenom could be produced inexpensively and save many lives. This simple strategy and procedure could be readily adapted for the production of pan-specific antisera against elapids of other continents.  相似文献   
202.

Key message

Single nucleotide polymorphism in sugar pathway and disease resistance genes showing genetic association with sugar content and red rot resistance would be useful in marker-assisted genetic improvement of sugarcane.

Abstract

Validation and genotyping of potential sequence variants in candidate genes are necessary to understand their functional significance and trait association potential. We discovered, characterized, validated and genotyped SNPs and InDels in sugar pathway and disease resistance genes of Saccharum complex and sugarcane varieties using amplicon sequencing and CAPS assays. The SNPs were abundant in the non-coding 3′UTRs than 5′UTRs and coding sequences depicting a strong bias toward C to T transition substitutions than transversions. Sequencing of cloned amplicons validated 61.6 and 45.2 % SNPs detected in silico in 21 sugar pathway and 16 disease resistance genes, respectively. Sixteen SNPs in four sugar pathway genes and 10 SNPs in nine disease resistance genes were validated through cost-effective CAPS assay. Functional and adaptive significance of SNP and protein haplotypes identified in sugar pathway and disease resistance genes was assessed by correlating their allelic variation with missense amino acid substitutions in the functional domains, alteration in protein structure models and possible modulation of catalytic enzyme activity in contrasting high and low sugar and moderately red rot resistant and highly susceptible sugarcane genotypes. A strong genetic association of five SNPs in the sugar pathway and disease resistance genes, and an InDel marker in the promoter sequence of sucrose synthase-2 gene, with sugar content and red rot resistance, was evident. The functionally relevant SNPs and InDels, detected and validated in sugar pathway and disease resistance genes, and genic CAPS markers designed, would be of immense use in marker-assisted genetic improvement of sugarcane for sugar content and disease resistance.
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203.
Statistical screening of media components for production of lactic acid by Lactobacillus sp. KCP01 using date juice as a sugar source was carried out by Plackett-Burman design. Date juice at 5% sugar concentration when used alone showed 2.6 g/l of lactic acid production. Increase in lactic acid production (15.1 g/l) was observed with supplementation of salts and organic nitrogen sources of MRS medium and after optimization of pH and temperature using date juice as a C-source. Plackett-Burman design showed peptone, K2HPO4, sodium acetate and date juice as significant components influencing the lactic acid production.  相似文献   
204.
The biology and chemistry of hyperlipidemia   总被引:2,自引:0,他引:2  
Coronary arterial diseases are responsible for more deaths than all other associated causes combined. Elevated serum cholesterol levels leading to atherosclerosis can cause coronary heart disease (CHD). Reduction in serum cholesterol levels reduces the risk for CHD, substantially. Medicinal chemists all around the world have been designing, synthesizing, and evaluating a variety of new bioactive molecules for lowering lipid levels. This review summarizes the disorders associated with elevation of lipids in blood and the current strategies to control them. The emphasis has been laid in particular on the new potential biological targets and the possible treatments as well as the current ongoing research status in the field of lipid lowering agents.  相似文献   
205.

Pigeonpea (Cajanus cajan L.) is a rich source of nutritionally good quality proteins, carbohydrates, minerals, and vitamins. However, environmental stresses adversely affect its productivity. Only limited reports are available on biochemical/physiological responses of pigeonpea under salt stress. The objectives of the present study were to screen pigeonpea germplasm accessions for salt stress tolerance, followed by understanding their biochemical, epigenetic and molecular responses. Based on germination, growth, and vigor of seedlings under salt stress, the most contrasting pair of salt-responsive genotypes (ICP1071- most salt-sensitive, and ICP7- most salt-tolerant) were selected. Three-week-old seedlings subjected to 250 mM NaCl stress for 7 days showed a significant increase in proline and reducing sugar contents in the case of ICP7, whereas a considerable increase in cell wall-degrading enzyme activity and protein oxidation was observed in ICP1071. Superoxide dismutase, peroxidase, and glutathione reductase activity increased considerably in shoots of ICP7. We observed the CcCYP gene to be upregulated in root, whereas CcCDR was upregulated in shoots of the salt-tolerant genotype to provide protection against the stress. The extent of DNA hypomethylation in the contrasting pigeonpea genotypes under salt stress was correlated with their salt tolerance level. Bisulfite sequencing of CcCDR revealed that methylation of three cytosine residues in CHH context in shoots of the ICP7 genotype due to salt stress results in 2.6-fold upregulated expression of the gene. With a 6.8% increase in methylation of the coding region of CcCDR, its expression level increased by 22%. To the best of our knowledge, this is the first report on a comprehensive study of salt-induced biochemical, epigenetic and molecular responses of pigeonpea, which might be useful in the development of improved salt-tolerant variety.

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206.
Vascular integrity is essential for organ homeostasis to prevent edema formation and infiltration of inflammatory cells. Long non‐coding RNAs (lncRNAs) are important regulators of gene expression and often expressed in a cell type‐specific manner. By screening for endothelial‐enriched lncRNAs, we identified the undescribed lncRNA NTRAS to control endothelial cell functions. Silencing of NTRAS induces endothelial cell dysfunction in vitro and increases vascular permeability and lethality in mice. Biochemical analysis revealed that NTRAS, through its CA‐dinucleotide repeat motif, sequesters the splicing regulator hnRNPL to control alternative splicing of tight junction protein 1 (TJP1; also named zona occludens 1, ZO‐1) pre‐mRNA. Deletion of the hnRNPL binding motif in mice (Ntras ∆CA/∆CA) significantly repressed TJP1 exon 20 usage, favoring expression of the TJP1α‐ isoform, which augments permeability of the endothelial monolayer. Ntras ∆CA/∆CA mice further showed reduced retinal vessel growth and increased vascular permeability and myocarditis. In summary, this study demonstrates that NTRAS is an essential gatekeeper of vascular integrity.  相似文献   
207.
What microbiology beholds after a decade and a half in the future requires a vision based on the facts and ongoing trends in research and technological advancements. While the latter, assisted by microbial dark matter, presents a greater potential of creating an upsurge in in-situ and ex-situ rapid microbial detection techniques, this anticipated change will also set forth a revolution in microbial cultivation and diversity analyses. The availability of a microbial genetic toolbox at the expanse will help complement the current understanding of the microbiome and assist in real-time monitoring of the dynamics for detecting the health status of the host with utmost precision. Alongside, in light of the emerging infectious diseases, antimicrobial resistance (AMR) and social demands for safer and better health care alternatives, microbiology laboratories are prospected to drift in terms of the volume and nature of research and outcomes. With today’s microbiological lens, one can predict with certainty that in the years to come, microbes will play a significant role in therapeutic treatment and the designing of novel diagnostic techniques. Another area where the scope of microbial application seems to be promising is the use of novel probiotics as a method to offer health benefits whilst promoting metabolic outputs specific for microbiome replenishment. Nonetheless, the evolution of extraterrestrial microbes or the adaptation of earth microbes as extraterrestrial residents are also yet another prominent microbial event one may witness in the upcoming years. But like the two sides of the coin, there is also an urgent need to dampen the bloom of urbanization, overpopulation and global trade and adopting sustainable approaches to control the recurrence of epidemics and pandemics.  相似文献   
208.
209.
Environmental constraints that include abiotic stress factors such as salt, drought, cold and extreme temperatures severely limit crop productivity. Improvement of crop plants with traits that confer tolerance to these stresses was practiced using traditional and modern breeding methods. Molecular breeding and genetic engineering contributed substantially to our understanding of the complexity of stress response. Mechanisms that operate signal perception, transduction and downstream regulatory factors are now being examined and an understanding of cellular pathways involved in abiotic stress responses provide valuable information on such responses. This review presents genomic-assisted methods which have helped to reveal complex regulatory networks controlling abiotic stress tolerance mechanisms by high-throughput expression profiling and gene inactivation techniques. Further, an account of stress-inducible regulatory genes which have been transferred into crop plants to enhance stress tolerance is discussed as possible modes of integrating information gained from functional genomics into knowledge-based breeding programs. In addition, we envision an integrative genomic and breeding approach to reveal developmental programs that enhance yield stability and improve grain quality under unfavorable environmental conditions of abiotic stresses.  相似文献   
210.
Medicinal and aromatic plants (MAPs) contribute to human well‐being via health and economic benefits. Nepal has recorded 2331 species of MAPs, of which around 300 species are currently under trade. Wild harvested MAPs in Nepal are under increasing pressure from overexploitation for trade and the effects of climate change and development. Despite some localized studies to examine the impact of climate change on MAPs, a consolidated understanding is lacking on how the distribution of major traded species of MAPs will change with future climate change. This study identifies the potential distribution of 29 species of MAPs in Nepal under current and future climate using an ensemble modeling and hotspot approach. Future climate change will reduce climatically suitable areas of two‐third of the studied species and decrease climatically suitable hotspots across elevation, physiography, ecoregions, federal states, and protected areas in Nepal. Reduction in climatically suitable areas for MAPs might have serious consequences for the livelihood of people that depend on the collection and trade of MAPs as well as Nepal''s national economy. Therefore, it is imperative to consider the threats that future climate change may have on distribution of MAPs while designing protected areas and devising environmental conservation and climate adaptation policies.  相似文献   
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