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101.
Serological Relationship of the Tacaribe Complex of Viruses to Lymphocytic Choriomeningitis Virus 总被引:5,自引:3,他引:2 下载免费PDF全文
Wallace P. Rowe Wendell E. Pugh Patricia A. Webb Clarence J. Peters 《Journal of virology》1970,5(3):289-292
By means of the indirect fluorescent-antibody test, cross serological reactivity was demonstrated between lymphocytic choriomeningitis (LCM) virus and the viruses of the Tacaribe complex. Antisera to all members of the Tacaribe complex reacted with LCM virus; LCM antisera gave significant staining of Amapari virus, but minimal or inconsistent reactions with Tacaribe virus, and no reaction with two other viruses of the Tacaribe complex. A low level cross-reaction was observed in complement fixation tests of Machupo and Pichinde antisera against LCM antigen. Immunization with Tacaribe and Amapari viruses did not protect mice against challenge with LCM virus. Because of the identical appearance of the virions, the sharing of antigens, and the many biological similarities between LCM and the Tacaribe complex viruses, it is proposed that they be considered as constituting a new taxonomic group of viruses. 相似文献
102.
Wendell D. Gingrich 《Biotechnic & histochemistry》1941,16(4):159-164
Fixing thick films in alcoholic solution of dye after the usual staining-and-laking procedure preserves the appearance of parasites and blood elements very similar to that of the usual thick films (not fixed) for the diagnosis of malaria and relapsing fever.
Procedure recommended: Films are stained and laked for 15 minutes in diluted Giemsa—1 to 3 drops of stock solution (0.4 g. in 60 ml. equal parts absolute methyl alcohol and glycerin) per ml. distilled water; rinsed in water and allowed to dry. They are then immersed in, or flooded with, May-Griinwald's stain (0.5% in absolute methyl alcohol) for 30 seconds, rinsed in water and allowed to dry. Solutions of MacNeal's tetrachrome stain in methyl alcohol and glycerin may be substituted for Giemsa and a solution in methyl alcohol may be substituted for May-Griinwald. With slight modification of the procedure, both thick and thin films on the same slide may be stained together.
Films stained and fixed as described, and mounted in Diaphane, have shown no evidence of fading in 3 years. 相似文献
Procedure recommended: Films are stained and laked for 15 minutes in diluted Giemsa—1 to 3 drops of stock solution (0.4 g. in 60 ml. equal parts absolute methyl alcohol and glycerin) per ml. distilled water; rinsed in water and allowed to dry. They are then immersed in, or flooded with, May-Griinwald's stain (0.5% in absolute methyl alcohol) for 30 seconds, rinsed in water and allowed to dry. Solutions of MacNeal's tetrachrome stain in methyl alcohol and glycerin may be substituted for Giemsa and a solution in methyl alcohol may be substituted for May-Griinwald. With slight modification of the procedure, both thick and thin films on the same slide may be stained together.
Films stained and fixed as described, and mounted in Diaphane, have shown no evidence of fading in 3 years. 相似文献
103.
Studies on the Growth of the Red Alga Porphyridium cruentum 总被引:6,自引:0,他引:6
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107.
Jyotsna Pandey Karen A. Gould Rodney D. McComb James D. Shull Douglas L. Wendell 《Mammalian genome》2005,16(11):865-872
In some rat strains chronic administration of exogenous estrogens induces pyometritis, an inflammation of the uterus associated
with infection, suggesting that there is genetic variation in susceptibility to estrogen-induced inflammation and pyometritis.
In this article we report that following 10 weeks of treatment with the synthetic estrogen diethylstilbestrol (DES), Fisher
344 (F344) rats exhibit modest uterine inflammation and a 0% incidence of pyometritis. By contrast, under identical experimental
conditions, Brown Norway (BN) rats exhibit significant inflammation and a 100% incidence of pyometritis. Similarly, we also
observed profound uterine inflammation and a 100% incidence of pyometritis in a congenic rat strain in which a segment of
RNO5 from the BN strain is carried on the F344 strain. These data suggest that a locus on RNO5 controls both the magnitude
of DES-induced uterine inflammation and susceptibility to DES-induced pyometritis. This locus, designated Eutr2, resides within the same segment of RNO5 as the Eutr1 locus, which confers susceptibility to E2-induced pyometritis in an F2 population generated in a cross between the BN and
August × Copenhagen 9935, Irish (ACI) strains.
Jyotsna Pandey, Karen A. Gould contributed equally to this work. 相似文献
108.
Roles of RNA polymerase IV in gene silencing 总被引:2,自引:0,他引:2
Eukaryotes typically have three multi-subunit enzymes that decode the nuclear genome into RNA: DNA-dependent RNA polymerases I, II and III (Pol I, II and III). Remarkably, higher plants have five multi-subunit nuclear RNA polymerases: the ubiquitous Pol I, II and III, which are essential for viability; plus two non-essential polymerases, Pol IVa and Pol IVb, which specialize in small RNA-mediated gene silencing pathways. There are numerous examples of phenomena that require Pol IVa and/or Pol IVb, including RNA-directed DNA methylation of endogenous repetitive elements, silencing of transgenes, regulation of flowering-time genes, inducible regulation of adjacent gene pairs, and spreading of mobile silencing signals. Although biochemical details concerning Pol IV enzymatic activities are lacking, genetic evidence suggests several alternative models for how Pol IV might function. 相似文献
109.
Hermann Cuntz Friedrich Forstner Juergen Haag Alexander Borst 《PLoS computational biology》2008,4(12)
Dendrite morphology, a neuron's anatomical fingerprint, is a neuroscientist's asset in unveiling organizational principles in the brain. However, the genetic program encoding the morphological identity of a single dendrite remains a mystery. In order to obtain a formal understanding of dendritic branching, we studied distributions of morphological parameters in a group of four individually identifiable neurons of the fly visual system. We found that parameters relating to the branching topology were similar throughout all cells. Only parameters relating to the area covered by the dendrite were cell type specific. With these areas, artificial dendrites were grown based on optimization principles minimizing the amount of wiring and maximizing synaptic democracy. Although the same branching rule was used for all cells, this yielded dendritic structures virtually indistinguishable from their real counterparts. From these principles we derived a fully-automated model-based neuron reconstruction procedure validating the artificial branching rule. In conclusion, we suggest that the genetic program implementing neuronal branching could be constant in all cells whereas the one responsible for the dendrite spanning field should be cell specific. 相似文献
110.
Stefan Stich Marion Haag Thomas Häupl Orhan Sezer Michael Notter Christian Kaps Michael Sittinger Jochen Ringe 《Cell and tissue research》2009,336(2):225-236
In situ tissue engineering is a promising approach in regenerative medicine, with the possibility that adult stem or progenitor
cells will be guided chemotactically to a tissue defect and subsequently differentiate into the surrounding tissue type. Mesenchymal
stem cells (MSC) represent attractive candidate cells. Chemokines such as CXCL12 (SDF-1α) chemoattract MSC, but little is
known about the molecular processes involved in the chemotaxis and migration of MSC. In this study, MSC recruitment by CXCL12
was investigated by genome-wide microarray analysis. The dose-dependent migration potential of bone-marrow-derived MSC toward
CXCL12 was measured in an in vitro assay, with a maximum being recorded at a concentration of 1,000 nM CXCL12. Microarray
analysis of MSC stimulated with CXCL12 and non-stimulated controls showed 30 differentially expressed genes (24 induced and
six repressed). Pathway analysis revealed 11 differentially expressed genes involved in cellular movement and cytokine-cytokine
receptor interaction, including those for migratory inducers such as the chemokines CXCL8 and CCL26, the leukocyte inhibitory
factor, secretogranin II, and prostaglandin endoperoxide synthase 2. These results were confirmed by real-time polymerase
chain reaction for selected genes. The obtained data provide further insights into the molecular mechanisms involved in chemotactic
processes in cell migration and designate CXCL12 as a promising candidate for in situ recruitment in regenerative therapies.
Stefan Stich and Marion Haag contributed equally to this work.
This study was supported by the Investitionsbank Berlin and the European Regional Development Fund (grant: 10128098), Deutsche
Forschungsgemeinschaft (grant: DFG SI 569/7–1), and the Bundesministerium für Bildung und Forschung (Bioinside: 13N9817). 相似文献