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671.
R. Sharma V. P. Rao R. K. Varshney V. P. Prasanth S. Kannan R. P. Thakur 《Archives Of Phytopathology And Plant Protection》2013,46(6):538-551
Genotypic diversity among 46 isolates of Sclerospora graminicola collected from seven states in India during 1992–2005 was determined through pathotyping and AFLP analysis. A high level of variation was observed among the isolates for downy mildew incidence, latent period and virulence index. Based on the reaction on a set of nine pearl millet lines, 46 isolates were classified in 21 pathotypes. Quantitative differences in virulence levels of the test isolates were assessed by calculating the virulence index (disease incidence × latent period ? 1). A dendrogram generated by the average linkage cluster analysis of virulence index clustered the 46 isolates into eight groups. Region-specific grouping of five isolates from Gujarat and six from Rajasthan was observed within two distinct groups. Temporal variation was also observed among the isolates collected from the same location and same host over the years. A total of 297 bands were scored following selective amplification with three primer combinations E-TT/M-CAG, E-AT/M-CAG and E-TG/M-CAT and all of them were polymorphic. Cluster analysis of AFLP data clustered the test isolates into seven groups. Analysis of molecular variance indicated that variation in the S. graminicola populations was largely due to differences among the isolates within the states. 相似文献
672.
Antifungal activity of phytochemicals from Eucalyptus hybrid leaves against some plant pathogenic and wood decay fungi 总被引:1,自引:0,他引:1
Vinay Kumar Varshney Amit Pandey Praveen Kumar Onial Rameshwar Dayal 《Archives Of Phytopathology And Plant Protection》2013,46(19):2347-2354
The in vitro fungitoxicity of the essential oil (EO), crude extracts, dried fractions and ursolic acid (UA) isolated from the abundantly available and underutilised leaves of Eucalyptus hybrid (Eucalyptus camaldulensis × Eucalyptus tereticornis) was assessed against three plant pathogenic fungi Aspergillus niger, Fusarium solani and Ganoderma lucidum causing pathogenesis in seeds, seedlings and trees, respectively, and Trametes versicolor and Pycnoporous sanguineus making wood to decay. The EO, methanol extract and UA demonstrated varied antifungal activity against all the fungi with minimum inhibitory concentrations ranging from 0.5 to 3.0%. The results of the study demonstrate a new chemical utilisation approach of the leaves of Eucalyptus hybrid towards the development of biofungicides in the management of above fungi of common occurrence in Indian forestry. 相似文献
673.
Michael A. Carpenter Ming Li Anurag Rathore Lela Lackey Emily K. Law Allison M. Land 《Journal of biomolecular structure & dynamics》2013,31(1)
Multiple studies have indicated that the TET oxidases and, more controversially, the AID/APOBEC deaminases have the capacity to convert genomic DNA 5-methyl-cytosine (MeC) into altered nucleobases that provoke excision repair and culminate in the replacement of the original MeC with a normal cytosine (C). We show that human APOBEC3A (A3A) efficiently deaminates both MeC to thymine (T) and normal C to uracil (U) in single-stranded DNA substrates. In comparison, the related enzyme APOBEC3G (A3G) has undetectable MeC-to-T activity and 10-fold less C-to-U activity. Upon 100-fold induction of endogenous A3A by interferon, the MeC status of bulk chromosomal DNA is unaltered whereas both MeC and C nucleobases in transfected plasmid DNA substrates are highly susceptible to editing. Knockdown experiments show that endogenous A3A is the source of both of these cellular DNA deaminase activities. This is the first evidence for non-chromosomal DNA MeC-to-T editing in human cells. These biochemical and cellular data combine to suggest a model in which the expanded substrate versatility of A3A may be an evolutionary adaptation that occurred to fortify its innate immune function in foreign DNA clearance by myeloid lineage cell types. 相似文献
674.
Markus-Frederik Bohn Shivender M.D. Shandilya John S. Albin Takahide Kouno Brett D. Anderson Rebecca M. McDougle Michael A. Carpenter Anurag Rathore Leah Evans Ahkillah N. Davis JingYing Zhang Yongjian Lu Mohan Somasundaran Hiroshi Matsuo Reuben S. Harris Celia A. Schiffer 《Structure (London, England : 1993)》2013,21(6):1042-1050
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675.
OBJECTIVE: To evaluate the usefulness of toluidine blue and brush biopsy in precancerous oral lesions and squamous cell carcinoma. STUDY DESIGN: The study was conducted at Moti Lal Nehru Medical College, Allahabad, India. Ninety-six patients with suspicious oral lesions who attended the outpatient clinics of otorhinolaryngology were screened with in vivo toluidine blue staining and oral brush biopsy. RESULTS: Oral brush biopsy showed high specificity and sensitivity. Toluidine blue staining was highly sensitive and moderately specific for malignant lesions but less sensitive for premalignant lesions. CONCLUSIONS: Early detection of oral carcinoma is possible even at the precancerous stages by using noninvasive, painless and outpatient procedures, such as in vivo toluidine blue staining and brush biopsy. 相似文献
676.
Mukherjee TK Mishra AK Mukhopadhyay S Hoidal JR 《Journal of immunology (Baltimore, Md. : 1950)》2007,178(3):1835-1844
In endothelial cells, the intracellular level of glutathione is depleted during offering protection against proinflammatory cytokine TNF-alpha-induced oxidative stress. Administration of anti-inflammatory drugs, i.e., N-acetylcysteine (NAC) or mitoquinone-Q (mito-Q) in low concentrations in the human pulmonary aortic endothelial cells offered protection against depletion of reduced glutathione and oxidative stress mediated by TNF-alpha. However, this study addressed that administration of NAC or mito-Q in high concentrations resulted in a biphasic response by initiating an enhanced generation of both reduced glutathione and oxidized glutathione and enhanced production of reactive oxygen species, along with carbonylation and glutathionylation of the cellular proteins. This study further addressed that IkappaB kinase (IKK), a phosphorylation-dependent regulator of NF-kappaB, plays an important regulatory role in the TNF-alpha-mediated induction of the inflammatory cell surface molecule ICAM-1. Of the two catalytic subunits of IKK (IKKalpha and IKKbeta), low concentrations of NAC and mito-Q activated IKKalpha activity, thereby inhibiting the downstream NF-kappaB and ICAM-1 induction by TNF-alpha. High concentrations of NAC and mito-Q instead caused glutathionylation of IKKalpha, thereby inhibiting its activity that in turn enhanced the downstream NF-kappaB activation and ICAM-1 expression by TNF-alpha. Thus, establishing IKKalpha as an anti-inflammatory molecule in endothelial cells is another focus of this study. This is the first report that describes a stressful situation in the endothelial cells created by excess of antioxidative and anti-inflammatory agents NAC and mito-Q, resulting in the generation of reactive oxygen species, carbonylation and glutathionylation of cellular proteins, inhibition of IKKalpha activity, and up-regulation of ICAM-1expression. 相似文献
677.
Varshney RK Marcel TC Ramsay L Russell J Röder MS Stein N Waugh R Langridge P Niks RE Graner A 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2007,114(6):1091-1103
A microsatellite or simple sequence repeat (SSR) consensus map of barley was constructed by joining six independent genetic maps based on the mapping populations 'Igri x Franka', 'Steptoe x Morex', 'OWB(Rec) x OWB(Dom)', 'Lina x Canada Park', 'L94 x Vada' and 'SusPtrit x Vada'. Segregation data for microsatellite markers from different research groups including SCRI (Bmac, Bmag, EBmac, EBmag, HVGeneName, scsssr), IPK (GBM, GBMS), WUR (GBM), Virginia Polytechnic Institute (HVM), and MPI for Plant Breeding (HVGeneName), generated in above mapping populations, were used in the computer program RECORD to order the markers of the individual linkage data sets. Subsequently, a framework map was constructed for each chromosome by integrating the 496 "bridge markers" common to two or more individual maps with the help of the computer programme JoinMap 3.0. The final map was calculated by following a "neighbours" map approach. The integrated map contained 775 unique microsatellite loci, from 688 primer pairs, ranging from 93 (6H) to 132 (2H) and with an average of 111 markers per linkage group. The genomic DNA-derived SSR marker loci had a higher polymorphism information content value (average 0.61) as compared to the EST/gene-derived SSR loci (average 0.48). The consensus map spans 1,068 cM providing an average density of one SSR marker every 1.38 cM. Such a high-density consensus SSR map provides barley molecular breeding programmes with a better choice regarding the quality of markers and a higher probability of polymorphic markers in an important chromosomal interval. This map also offers the possibilities of thorough alignment for the (future) physical map and implementation in haplotype diversity studies of barley. 相似文献
678.
Agrawal AA 《Trends in ecology & evolution》2007,22(2):103-109
Theories of plant defense expression are typically based on the concepts of tradeoffs among traits and of phylogenetic conservatism within clades. Here, I review recent developments in phylogenetic approaches to understanding the evolution of plant defense strategies and plant-herbivore coevolutionary interactions. I focus particularly on multivariate defense against insect herbivores, which is the simultaneous deployment of multiple traits, often arranged as convergently evolved defense syndromes. Answering many of the outstanding questions in the biology of plant defense will require generating broad hypotheses that can be explicitly tested by using comparative approaches and interpreting phylogenetic patterns. The comparative approach has wide-spread potential to reinvigorate tests of classic hypotheses about the evolution of interspecific interactions. 相似文献
679.
680.
Mamta Sharma Avuthu Nagavardhini Mahendar Thudi Raju Ghosh Suresh Pande Rajeev K Varshney 《BMC genomics》2014,15(1)