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31.
Detection of cross reactive antigens between Pestalotiopsis theae and tea leaves and their cellular location 总被引:1,自引:0,他引:1
B. N. CHAKRABORTY P. BASU R. DAS A. SAHA U. CHAKRABORTY 《The Annals of applied biology》1995,127(1):11-21
Among the 12 varieties of tea tested against three isolates of Pestalotiopsis theae, causal agent of grey blight disease, Teen Ali-17/1/54 and TV-23 were found to be highly susceptible while CP-1 and TV-26 were resistant under identical conditions. Leaf antigens were prepared from all the tea varieties, three isolates of P. theae and a non-pathogen of tea (Bipolaris tetramera). Polyclonal antisera were raised against mycelial suspensions of P. theae (isolate Pt-2) and leaf antigens of Teen Ali-17/1/54 and CP-1. These were compared an immunodiffusion test and enzyme-linked immunosorbent assay to detect cross reactive antigens (CRA) shared the host and the parasite. CRA were found among the susceptible varieties and isolates of P. theae (Pt-1, 2 and 3). Such antigens were not detected between isolates of P. theae and resistant varieties, B. tetramera and tea varieties or isolates of P. theae. Indirect staining of antibodies using fluorescein isothiocyanate (FITC) indicated that in cross sections of tea leaves, the CRA was concentrated in the epidermal cells and mesophyll tissues. CRA was present in the young hyphal tips of the mycelia and on the setulae and appendages of the conidia of P. theae. 相似文献
32.
JAYNE E. ELLIS MICHAEL A. WYDER LINDA ZHOU ARUN GUPTA HARRY RUDNEY EDNA S. KANESHIRO 《The Journal of eukaryotic microbiology》1996,43(3):165-170
The lipids of purified preparations of Pneumocystis carinii carinii freshly isolated from infected rats were analyzed and compared with those of whole lungs from normal and methylprednisolone-immunosuppressed uninfected rats. In this study, the neutral lipid fraction was examined in detail; the relative concentrations of individual classes making up this fraction were quantified. Of particular interest was the nature of the organism's ubiquinone (coenzyme Q, CoQ) fraction because atovaquone, a hydroxynaphtho-quinone (566C80) analog of ubiquinone, is efficacious in the treatment of P. carinii pneumonia. The ubiquinone concentration in both P. carinii and lung tissues was relatively low compared to that present in rat heart and liver tissues. Two homologs were identified in the organism: CoQ10 was the predominant homolog with lesser amounts of CoQ9 present. In contrast, the lungs of normal and immunosuppressed uninfected rats had CoQ9 and lesser amounts of CoQ8 , but no detectable CoQ10 . Furthermore, radiolabeled mevalonic acid was incorporated in vitro into the ubiquinone fraction of P. carinii indicating that the organism has the de novo branch of the isoprenoid biosynthetic pathway leading to polyprenyl formation. Hence, it was concluded that CoQ10 (if not both CoQ110 and CoQ9 ) in P. carinii as not scavenged from the host but was synthesized by the organism. Although lung tissues contained substantial free fatty acids, the organism was enriched in these lipids. The high concentration of free fatty acids and relatively low level of triglycerides in P. carinii suggest that fatty acids may represent major carbon sources for ATP production by the organism. 相似文献
33.
D. GUPTA G. BREITMAIER W. VOELTER G. JUNG E. BREITMAIER W. KÖNIG 《Nature: New biology》1972,235(54):55-56
DURING a longitudinal investigation on the changes in urinary steroid profile with sexual maturation in healthy children, a new steroid-like substance, giving most of the well known steroid reactions, was found1. Since then, the substance has appeared consistently in microgram quantities on urinary steroid chromatograms in our laboratory2, running close to 11β-hydroxyandrosterone in the Bush B3 system3. Similar substances have been noted by other workers (Drs D. M. Cathro, C. C. Forsyth and J. Bertrand, personal communications). Children suffering from lipodystrophy, progeria and leucine-sensitive hypoglycaemia excreted this substance in larger quantities than the normals4. 相似文献
34.
HAPLOIDS from higher eukaryotes are of great importance for genetic analysis1. The observation of Morpurgo2 that haploid segregants can be obtained from diploid lines of Aspergillus nidulans by parafluorophenylalanine (PFP) treatment suggests that defined chemical manipulations may be useful in generating and maintaining haploid cells in cultures of higher plants. Parafluorophenylalanine has been found to induce haploidization not only in some species of Aspergillus, but also in some other genera of fungi such as Ustilago3. 相似文献
35.
36.
Pseudomyxoma peritonei and the cytologist 总被引:4,自引:0,他引:4
37.
Studies to determine the variations in leucine aminopeptidase(LAP) activity in tall and dwarf cultivars of rice were conductedby horizontal starch gel electrophoresis. The samples were takenat weekly intervals starting with soaked seeds (12 h) untilthe post-panicle stage. There is a distinct pattern of LAP isoenzymesin tall and dwarf cultivars studied. Some isoenzymes appearat a particular developmental stage and others disappear whilesome remain fairly constant once they are formed. A tall cultivar(Hansraj) shows greater fluctuations during the course of developmentthan the dwarf cultivars. These studies throw light on the transitorynature of these enzymes and show apparently differential geneaction. 相似文献
38.
39.
ANDREA FERREIRA DA COSTA PABLO JOSÉ FRANCISCO PENA RODRIGUES MARIA DAS GRAÇAS LAPA WANDERLEY 《Botanical journal of the Linnean Society. Linnean Society of London》2009,159(1):163-181
The species related to Vriesea paraibica (Bromeliaceae, Tillandsioideae) have controversial taxonomic limits. For several decades, this group has been identified in herbarium collections as V. × morreniana, an artificial hybrid that does not grow in natural habitats. The aim of this study was to assess the morphological variation in the V. paraibica complex through morphometric analyses of natural populations. Two sets of analyses were performed: the first involved six natural populations (G1) and the second was carried out on taxa that emerged from the first analysis, but using material from herbarium collections (G2). Univariate ANOVA was used, as well as discriminant analysis of 16 morphometric variables in G1 and 18 in G2. The results of the analyses of the two groups were similar and led to the selection of diagnostic traits of four species. Lengths of the lower and median floral bracts were significant for the separation of red and yellow floral bracts. Vriesea paraibica and V. interrogatoria have red bracts; these two species are differentiated by the widths of the lower and median portions of the inflorescence and by scape length. These structures are larger in the former and smaller in the latter. Of the species with yellow floral bracts, V. eltoniana is distinguished by longer leaf blades and scapes and V. flava is characterized by its shorter sepal lengths. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 159 , 163–181. 相似文献
40.
Development and use of anchored‐SSRs to study DNA polymorphism in bread wheat (Triticum aestivum L.)
RAVINDER SINGH NEERAJ KUMAR RAJIB BANDOPADHYAY SACHIN RUSTGI SHAILENDRA SHARMA HARINDRA SINGH BALYAN PUSHPENDRA KUMAR GUPTA 《Molecular ecology resources》2006,6(1):296-299
In bread wheat, 21 anchored simple sequence repeat (SSR) primer pairs detecting SSR length polymorphism and 42 anchored SSR primers detecting microsatellite‐anchored fragment length polymorphisms (MFLPs) are reported. Eight bread wheat genotypes were used for detecting polymorphism. The number of alleles in SSR analysis ranged from two to six, with a mean of 2.9 alleles per SSR. The number of polymorphic bands in MFLP ranged from two to 40, with a mean of 12.74 polymorphic bands/primer combination, the SSRs with CT/GA motifs giving the highest level of polymorphism (a mean of 18.37 bands). The average value of polymorphic information content (PIC) was 0.473 for SSRs and 0.061 for MFLP. 相似文献