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排序方式: 共有86条查询结果,搜索用时 12 毫秒
61.
JAN E. JANEČKA LON I. GRASSMAN JR. RODNEY L. HONEYCUTT MICHAEL E. TEWES 《The Journal of wildlife management》2007,71(4):1357-1360
Abstract: We describe a method for rapidly amplifying whole genomes via a Phi29 DNA polymerase-mediated strand displacement reaction (SDR). Genomic amplification products derived from the SDR reaction resulted in high quantities of DNA suitable for polymerase chain reaction (PCR) amplification and sequencing of mitochondrial genomes. Control region sequences of DNA derived directly from PCR amplicons of extracted DNA were identical to those derived from PCR amplification of SDR genomic DNA. Effective SDR amplification and subsequent sequencing was successful across tissues sources ranging in age from 1 year to 19 years. Strand replacement reaction genomic amplification offers a means of obtaining large quantities of DNA from small amounts of tissue. 相似文献
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Measures of population productivity and individual survival are essential for effective conservation management and scientific investigations. In studies of birds, individuals are often marked with unique colour band combinations to enable estimates of population vital rates. If birds are banded in the nest this must be done at the correct stage in nestling development. If nestlings are banded too early it can lead to leg damage. If they are banded too late it can cause early fledging and reduced survival. Here, we use photographs to guide estimation of the best stage to band North Island robin (Petroica longipes), or toutouwai, nestlings, which is typically at 9–12 days of age. 相似文献
65.
Multiple interspecies transmissions of human and simian T-cell leukemia/lymphoma virus type I sequences 总被引:8,自引:0,他引:8
Using two sets of nucleotide sequences of the human and simian T-cell
leukemia/lymphoma virus type I (HTLV-I/STLV-I), one consisting of 522 bp of
the env gene from 70 viral strains and the other a 140-bp segment from the
pol gene of 52 viral strains, I estimated cladograms based on a statistical
parsimony procedure that was developed specifically to estimate
within-species gene trees. An extension of a nesting procedure is offered
for sequence data that forms nested clades used in hypothesis testing. The
nested clades were used to test three hypotheses relating to transmission
of HTLV/STLV sequences: (1) Have cross-species transmissions occurred and,
if so, how many? (2) In what direction have they occurred? (3) What are the
geographic relationships of these transmission events? The analyses support
a range of 11-16 cross-species transmissions throughout the history of
these sequences. Additionally, outgroup weights were assigned to haplotypes
using arguments from coalescence theory to infer directionality of
transmission events. Conclusions on geographic origins of transmission
events and particular viral strains are inconclusive due to small samples
and inadequate sampling design. Finally, this approach is compared directly
to results obtained from a traditional maximum parsimony approach and found
to be superior at establishing relationships and identifying instances of
transmission.
相似文献
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68.
ZDENK IKA 《The Journal of eukaryotic microbiology》1978,25(1):50-56
SYNOPSIS. The fine structure of schizonts and free merozoites of the neogregarine Farinocystis tribolii Weiser, and their development in the fat body of larval Tribolium castaneum were studied.
The surface of a multinucleate schizont and that of a uninucleate merozoite is covered by a double-layered membrane. Rhoptries and micronemes are present. The cytoplasm is packed with ribosomes and also contains dark bodies. Mitochondria are of the vesicular type. The spherical nucleus of the schizont and merozoite contains a large nucleolus. The anterior end of the merozoite has a typical conoidal complex composed of a conoid and a polar ring with 22 subpellicular mirotubules projecting from it.
New findings are a membranous septum across the body of the merozoite at 2/3 of its length below the nucleus and a highly osmiophilic spiral structure in the perinuclear space close to the Golgi complex. In addition, we found some "developmental stages" of the latter structure. 相似文献
The surface of a multinucleate schizont and that of a uninucleate merozoite is covered by a double-layered membrane. Rhoptries and micronemes are present. The cytoplasm is packed with ribosomes and also contains dark bodies. Mitochondria are of the vesicular type. The spherical nucleus of the schizont and merozoite contains a large nucleolus. The anterior end of the merozoite has a typical conoidal complex composed of a conoid and a polar ring with 22 subpellicular mirotubules projecting from it.
New findings are a membranous septum across the body of the merozoite at 2/3 of its length below the nucleus and a highly osmiophilic spiral structure in the perinuclear space close to the Golgi complex. In addition, we found some "developmental stages" of the latter structure. 相似文献
69.
Abstract The palatability to common carp, Cyprinus carpio L. of three newly developed differently flavoured floating pellets made from a high proportion (40%) of brewer's spent grain (BSG) was tested using a multiple-offer feeding experiment. The addition of ‘bold’ flavours, such as vanilla or strawberry essence, may help mask the unpleasant taste of some piscicides; however, their inclusion must not compromise uptake by carp. There were no significant differences between the consumption rates of the three varieties, and all flavours were readily consumed. Therefore, it is suggested that highly flavoured pellets made with BSG have a strong potential to mask the flavour of an unpalatable toxin, and further research is now needed to test this hypothesis. 相似文献
70.
Lennart KA Lundblad Lisa M Rinaldi Matthew E Poynter Erik P Riesenfeld Min Wu Steven Aimi Leesa M Barone Jason HT Bates Charles G Irvin 《Respiratory research》2011,12(1):27