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71.
The complex preparations (CP) containing yeast mannan, diacetyl-2,4-dioxihexahydro-1,3,5-triasyne, cyanoguanidine, alcan-sulfo-acids, or secondary metabolites of Pseudomonas sp. manifest in the inhibitory activity against tumors induced by A. tumefaciens in the parenchymatous tissue of potato tubers. As a rule, antitumor activity of CP is higher in the prophylactic application compared to the therapeutic application of the preparations.  相似文献   
72.
Morphological features of a collection of unknown-age wild kiwi (Apteryx mantelli) embryos from early development to point of hatch are described. Using these features, we assign developmental stages to each embryo and compare the progress of development to similar-staged ostrich (Struthio camelus) and chicken (Gallus gallus) embryos. Two ageing schemes for the kiwi embryos are developed by comparing measurements of their hindlimb segments, bills and crown–rump lengths with those of ostrich and chicken embryos at various stages of development. One of the 20 kiwi embryos was of known age. Both the ostrich model and the chicken model gave identical predictions for the marker and four other embryos. Developmental timing of some features differed between all three species, most markedly in the bill, with growth in the kiwi bill being relatively faster to achieve its larger relative and absolute size at hatch.  相似文献   
73.
74.

Background

Parasites are evolutionary hitchhikers whose phylogenies often track the evolutionary history of their hosts. Incongruence in the evolutionary history of closely associated lineages can be explained through a variety of possible events including host switching and host independent speciation. However, in recently diverged lineages stochastic population processes, such as retention of ancestral polymorphism or secondary contact, can also explain discordant genealogies, even in fully co-speciating taxa. The relatively simple biogeographic arrangement of the Galápagos archipelago, compared with mainland biomes, provides a framework to identify stochastic and evolutionary informative components of genealogic data in these recently diverged organisms.

Results

Mitochondrial DNA sequences were obtained for four species of Galápagos mockingbirds and three sympatric species of ectoparasites - two louse and one mite species. These data were complemented with nuclear EF1α sequences in selected samples of parasites and with information from microsatellite loci in the mockingbirds. Mitochondrial sequence data revealed differences in population genetic diversity between all taxa and varying degrees of topological congruence between host and parasite lineages. A very low level of genetic variability and lack of congruence was found in one of the louse parasites, which was excluded from subsequent joint analysis of mitochondrial data. The reconciled multi-species tree obtained from the analysis is congruent with both the nuclear data and the geological history of the islands.

Conclusions

The gene genealogies of Galápagos mockingbirds and two of their ectoparasites show strong phylogeographic correlations, with instances of incongruence mostly explained by ancestral genetic polymorphism. A third parasite genealogy shows low levels of genetic diversity and little evidence of co-phylogeny with their hosts. These differences can mostly be explained by variation in life-history characteristics, primarily host specificity and dispersal capabilities. We show that pooling genetic data from organisms living in close ecological association reveals a more accurate phylogeographic history for these taxa. Our results have implications for the conservation and taxonomy of Galápagos mockingbirds and their parasites.  相似文献   
75.
Recent identification of the modular CLS motifs responsible for cyclins A and E localization on centrosomes has revealed a tight linkage between the nuclear and centrosomal cycles. These G1/S cyclins must localize on the centrosome in order for DNA replication to occur in the nucleus, whereas essential DNA replication factors also function on the centrosome to prevent centrosome overduplication. Both events are dependent on the presence of an intact CLS within each cyclin. Here we compare the cyclins A and E CLSs at the structural and functional levels and identify a new cyclin A CLS mutant that disrupts all CLS functions and reduces the affinity of cyclin A for Cdk2. Analysis of interactions of the CLS motif within the cyclin molecules highlights the importance of the cyclin CBOX1 region for Cdk2 binding.Key words: cyclin A, cyclin E, Cdk2, centrosome, CLS, PSTAIRE, DNA synthesis  相似文献   
76.

Background

The Vaccine Assessment using Linked Data (VALiD) trial compared opt-in and opt-out parental consent for a population-based childhood vaccine safety surveillance program using data linkage. A subsequent telephone interview of all households enrolled in the trial elicited parental intent regarding the return or non-return of reply forms for opt-in and opt-out consent. This paper describes the rationale for the trial and provides an overview of the design and methods.

Methods/Design

Single-centre, single-blind, randomised controlled trial (RCT) stratified by firstborn status. Mothers who gave birth at one tertiary South Australian hospital were randomised at six weeks post-partum to receive an opt-in or opt-out reply form, along with information explaining data linkage. The primary outcome at 10 weeks post-partum was parental participation in each arm, as indicated by the respective return or non-return of a reply form (or via telephone or email response). A subsequent telephone interview at 10 weeks post-partum elicited parental intent regarding the return or non-return of the reply form, and attitudes and knowledge about data linkage, vaccine safety, consent preferences and vaccination practices. Enrolment began in July 2009 and 1,129 households were recruited in a three-month period. Analysis has not yet been undertaken. The participation rate and selection bias for each method of consent will be compared when the data are analysed.

Discussion

The VALiD RCT represents the first trial of opt-in versus opt-out consent for a data linkage study that assesses consent preferences and intent compared with actual opting in or opting out behaviour, and socioeconomic factors. The limitations to generalisability are discussed.

Trial registration

Australian New Zealand Clinical Trials Registry ACTRN12610000332022  相似文献   
77.
78.
This review examines the main features of natural phytoalexines of flavonoid and stilbenoid natures, which are secondary metabolism products in numerous plants widely used as biologically active substances in the medicine, pharmacology, and agricultural plants protection. We considered the role of flavonoids and stilbenes in phytoimmune and antistress responses in plants, bactericide antifungul, and antiviral effects towards microorganisms, and the wide medical application for a number of mammalian pathologies. The main achievements in the metabolic engineering of flavonoids in microbial biotechnologies are discussed.  相似文献   
79.
Being devoted to studies in structural peculiarities of chromatin distribution of interphase nuclei from eucaryote cells, the paper embraces literature data and the authors' results in this field. Main tendencies in development of the method, based on the qualitative and quantitative estimation of hetero- and euchromatin nucleus substance are considered. Basic successes achieved while estimating experimental and clinical materials are indicated. It is determined as promising to put the method into practice.  相似文献   
80.
The Afanasievo Quarry, approximately 90 km southeast of Moscow and about 5 km southwest of Voskresensk, starts with Late Moscovian limestone of the Peski Formation, which is overlain by shallow-water carbonates of the Krevyakinian Horizon (Substage) (Suvorovo and Voskresensk formations) and the lower part of the Khamovnikian Horizon (Substage) (Ratmirovo and Neverovo formations). These rocks were formed under the strong influence of glacio-eustatic sea-level fluctuations and are separated by the palaeosol horizons and minor stratigraphic gaps. The Moscovian–Kasimovian transition interval contains fusulinids, brachiopods, bryozoans, corals, and conodonts. It was recently proposed [Villa, E., Task Group, 2005. Report of the Task Group to establish GSSPs at the Moscovian–Kasimovian and Kasimovian-Gzhelian boundaries. Newsletter on Carboniferous Stratigraphy 23, 9–10] that the appearance of the conodont Idiognathodus sagittalis Kozitskaya is one of the best markers for definition of the base of the Kasimovian on the global chronostratigraphic scale. The first appearance of this species is 2 m above the base of Neverovo Formation, and is close to the first appearance of the fusulinid Montiparus in the section. The possible ancestor of I. sagittalis occurs in the lower Suvorovo Formation, but is more abundant and more advanced in the middle to upper parts of the Voskresensk Formation. This lineage has potential for defining a GSSP at the first appearance of I. sagittalis.  相似文献   
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