全文获取类型
收费全文 | 50篇 |
免费 | 8篇 |
出版年
2021年 | 2篇 |
2016年 | 2篇 |
2014年 | 2篇 |
2013年 | 3篇 |
2012年 | 1篇 |
2011年 | 1篇 |
2010年 | 7篇 |
2009年 | 2篇 |
2008年 | 2篇 |
2006年 | 4篇 |
2005年 | 1篇 |
1998年 | 2篇 |
1997年 | 2篇 |
1996年 | 2篇 |
1994年 | 2篇 |
1992年 | 2篇 |
1991年 | 1篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1986年 | 1篇 |
1985年 | 2篇 |
1983年 | 3篇 |
1982年 | 4篇 |
1980年 | 1篇 |
1978年 | 1篇 |
1976年 | 1篇 |
1974年 | 1篇 |
1973年 | 1篇 |
1970年 | 1篇 |
1969年 | 1篇 |
1967年 | 1篇 |
排序方式: 共有58条查询结果,搜索用时 15 毫秒
21.
Mohamed Zouine Christophe Beloin Anne-Marie Deneubourg Luisa Hirschbein Françoise Le Hegarat 《FEMS microbiology letters》1996,145(1):41-48
Abstract Polyhydroxyalkanoate (PHA) accumulation and the morphology of PHA inclusion bodies were examined in Bacillus megaterium , strain 11561. Our results show a pattern of PHA degradation and synthesis, and of inclusion body growth and proliferation not previously reported. Degradation of PHA in the lag phase was followed by synthesis of PHA at an accelerating rate during exponential growth. PHA accumulation reached a maximum rate at late exponential/early stationary phase and the rate declined to a lower steady state in the stationary phase. During exponential and early stationary phase growth, PHA had a faster doubling rate than that of total cell biomass (w/w). Results of the morphology studies suggest that PHA inclusion bodies proliferated by budding and reached maximum size by early stationary phase growth. This pattern was observed in minimal and in rich media. 相似文献
22.
23.
W. THEUNIS S. BLÄHSER R. HUYBRECHTS A. DE LOOF 《Invertebrate reproduction & development.》2013,57(1-3):111-117
Summary Materials immunologically related to luteinising hormone (LH), follicle stimulating hormone (FSH) and the gonadotropin releasing hormone (GnRH) were localised in cerebral tissue of Locusta migratoria and Sarcophaga bullata by means of the peroxidase-antiperoxidase method. Several polyclonal and a monoclonal antisera were used. From the third larval instar a positive reaction was observed in cells located in several parts of the brain. Each antiserum reacted with a constant number of well defined cells and nerve fibers. No differences between sexes were observed. 相似文献
24.
A genome survey of Moniliophthora perniciosa gives new insights into Witches' Broom Disease of cacao
Jorge MC Mondego Marcelo F Carazzolle Gustavo GL Costa Eduardo F Formighieri Lucas P Parizzi Johana Rincones Carolina Cotomacci Dirce M Carraro Anderson F Cunha Helaine Carrer Ramon O Vidal Raíssa C Estrela Odalys García Daniela PT Thomazella Bruno V de Oliveira Acássia BL Pires Carolina S Maria Rio Marcos Renato R Araújo Marcos H de Moraes Luis AB Castro Karina P Gramacho Marilda S Gonçalves José P Moura Neto Aristóteles Góes Neto Luciana V Barbosa Mark J Guiltinan Bryan A Bailey Lyndel W Meinhardt Julio CM Cascardo Gonçalo AG Pereira 《BMC genomics》2008,9(1):1-25
25.
Michele Guescini Davide Sisti Marco BL Rocchi Laura Stocchi Vilberto Stocchi 《BMC bioinformatics》2008,9(1):326
Background
Real-time PCR analysis is a sensitive DNA quantification technique that has recently gained considerable attention in biotechnology, microbiology and molecular diagnostics. Although, the cycle-threshold (Ct) method is the present "gold standard", it is far from being a standard assay. Uniform reaction efficiency among samples is the most important assumption of this method. Nevertheless, some authors have reported that it may not be correct and a slight PCR efficiency decrease of about 4% could result in an error of up to 400% using the Ct method. This reaction efficiency decrease may be caused by inhibiting agents used during nucleic acid extraction or copurified from the biological sample. 相似文献26.
A simple, fast and sensitive method was developed to verify the presence of
the sialyl Lewis(x) antigen on an N-linked glycoprotein. High performance
liquid chromatography-electrospray mass spectrometry (HPLC-ESI/MS) was used
to identify which of the five N-linked glycosylation sites of human plasma
alpha1-acid-glycoprotein (orosomucoid, OMD) contain the sialyl Lewis(x)
antigen. OMD was digested with proteolytic enzymes and analyzed by reversed
phase chromatography coupled with on-line ESI/MS. A tandem mass
spectrometry experiment was designed to detect the presence of the sialyl
Lewis(x) antigen based on the observation of an 803 mass to charge ratio (
m/z ) ion produced in the intermediate pressure region of the ESI
interface. The ESI/MS signal at m/z 803 is consistent with an oxonium ion
for a glycan structure containing NeuAc, Gal, GlcNAc, and Fuc. The identity
of the m/z 803 ion was confirmed by ESI/MS/MS analysis of the m/z 803
fragment ion and comparison with a sialyl Lewis(x) standard. The
stereochemistry and linkage positions were assigned using previous NMR
analysis but could be determined with permethylation analysis if necessary.
The analysis of OMD gave a pattern showing signal for the sialyl Lewis(x)
antigen coeluting with each of the five N-linked glycopeptides. The ability
to monitor sialyl Lewis(x) expression at each of the five sites is of
interest in the study of OMD's role in inflammatory diseases.
相似文献
27.
Synemin and vimentin are components of intermediate filaments in avian erythrocytes 总被引:32,自引:21,他引:11
下载免费PDF全文
![点击此处可从《The Journal of cell biology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Synemin, a high-molecular-weight protein associated with intermediate filaments in muscle, and vimentin, an intermediate-filament subunit found in many different cell types, have been identified by immunologic and electrophoretic criteria as components of intermediate filaments in mature avian erythrocytes. Desmin, the predominant subunit of intermediate filaments in muscle, has not been detected in these cells. Two dimensional immunoautoradiography of proteolytic fragments of synemin and vimentin demonstates that the erythrocyte proteins are highly homologous, if not identical, to their muscle counterparts. Double immunoflurorescence reaveals that erythrocyte synemin and vimentin co-localize in a cytoplasmic network of sinuous filaments that extends from the nucleus to the plasma membrane and resists aggregation by colcemid. Erythrocytes that are attached to glass cover slips can be sonicated to remove nuclei and nonadherent regions of the plasma membrane; this leaves elliptical patches of adherent membrane that retain mats of vimentin- and synemin-containing intermediate filaments, as seen by immunofluorescence and rotary shadowing. Similarly, mechanical enucleation of erythrocyte ghosts in suspension allows isolation of plasma membranes that retain a significant fraction of the synemin and vimentin, as assayed by electrophoresis, and intermediate filaments, as seen in thin sections. Both synemin and vimentin remain insoluble along with spectrin and actin, in solutions containing nonionic detergent and high salt. However, brief exposure of isolated membrane to distilled water releases the synemin and vimentin together in nearly pure form, before the release of significant amounts of spectrin and actin. These data suggest that avian erythrocyte intermeditate filaments are somehow anchored to the plasma membrane; erythrocytes may thus provide a simple system for the study of intermediate filaments and their mode of interaction with membranes. In addition, these data, in conjunction with previous data from muscle, indicate that synemin is capable of associating with either desmin or vimentin and may thus perform a special role in the structure or function of intermediate filaments in erythrocytes as well as muscle. 相似文献
28.
Synthesis of Ribosomal Ribonucleic Acid During Sporulation of Bacillus subtilis 总被引:6,自引:3,他引:3
下载免费PDF全文
![点击此处可从《Journal of bacteriology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
The incorporation of radioactive uracil into 50s and 30s ribosomal subunits and ribosomal ribonucleic acid (rRNA) was studied during the growth cycle of different sporogenic and asporogenic strains of Bacillus subtilis. It was found that partially synchronized cultures of the strains examined incorporated labeled uracil into the two ribosomal subunit species and rRNA during sporulation and during the stationary phase of the asporogenic strains. Kinetic studies have shown that, compared to vegetative cells, the percentage of uracil incorporated into the ribosomal subunits of cells taken 30 min after the end of exponential growth was decreased by about 25 to 35%. This decrease, however, appeared to be a general characteristic of stationary-phase cells and seems to depend on the nature of the sporulation medium and to some extent on the nature of the strain but not on the sp(+) or sp(-) phenotype of the strain. Moreover, by use of actinomycin D it was shown that the labeled uracil incorporated, in the presence of the drug, during the sporulation period was located in the ribosomal subunits (stable RNA). Based on these results, we concluded that during sporulation ribosomal genes are transcribed and consequently rRNA continues to be synthesized, although to a lesser extent than during vegetative growth. These results are discussed in the light of those obtained by Hussey et al. 相似文献
29.
30.
1. The distribution of consumers among resources (trophic interaction network) may be shaped by asymmetric competition. Dominance hierarchy models predict that asymmetric interference competition leads to a domination of high quality resources by hierarchically superior species. 2. In order to determine the competitive dominance hierarchy and its effect on flower partitioning in a local stingless bee community in Borneo, interspecific aggressions were tested among eight species in arena experiments. 3. All species tested were strongly mutually aggressive in the arena, and the observed interactions were often lethal for one or both opponents. Aggression significantly increased with body size differences between fighting pairs and was asymmetric: larger aggressors were superior over smaller species. Additional aggression tests involved dummies with surface extracts, and results suggest that species‐ and colony‐specific surface profiles are important in triggering the aggressive behaviour. 4. Sixteen stingless bee species were observed foraging on 41 species of flowering plants. The resulting bee–flower interaction network showed a high degree of generalisation (network‐level specialisation H2’ = 0.11), corresponding to a random, opportunistic distribution of bee species among available flower species. 5. Aggressions on flowers were rare and only occurred at a low level. The dominance hierarchy obtained in the arena experiments did not correlate significantly with plant quality, estimated as the number of flowers per plant or as total bee visitation rate. 6. Our findings suggest that asymmetries in interference competition do not necessarily translate into actual resource partitioning in the context of complex interacting communities. 相似文献