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71.
TD Smith KP Bhatnagar CJ Bonar KL Shimp MP Mooney MI Siegel 《American journal of physical anthropology》2003,122(3):301-301
72.
AS Glen D Anderson CJ Veltman PM Garvey M Nichols 《New Zealand journal of zoology.》2016,43(2):127-137
A major challenge in controlling overabundant wildlife is monitoring their populations, particularly as they decline to very low density. Camera traps and wildlife detector dogs are increasingly being used for this purpose. We compared the cost-effectiveness of these two approaches for detecting feral cats (Felis catus) on two pastoral properties in Hawke's Bay, North Island, New Zealand. One property was subject to intensive pest removal, while the other had no recent history of pest control. Camera traps and wildlife detector dogs detected cats at similar rates at both sites. The operating costs of each method were also comparable. We identify a number of advantages and disadvantages of each technique, and suggest priorities for further research. 相似文献
73.
In the current model for Glc3Man9GlcNAc2-P-P-Dol assembly, Man5GlcNAc2-
P-P-Dol, Man-P-Dol, and Glc-P-Dol are synthesized on the cytoplasmic face
of the ER and diffuse transversely to the lumenal leaflet where the
synthesis of the lipid-bound precursor oligosaccharide is completed. To
establish the topological sites of Glc-P-Dol synthesis and the
lipid-mediated glucosyltransfer reactions involved in
Glc3Man9GlcNAc2-P-P-Dol synthesis in ER vesicles from pig brain, the
trypsin-sensitivity of Glc-P-Dol synthase activity and the Glc-P-
Dol:Glc0-2Man9GlcNAc2-P-P-Dol glucosyltransferases (GlcTases) was examined
in sealed microsomal vesicles. Since ER vesicles from brain do not contain
glucose 6-phosphate (Glc 6-P) phosphatase activity, the latency of the
lumenally oriented, processing glucosidase I/II activities was used to
assess the intactness of the vesicle preparations. Comparative enzymatic
studies with sealed ER vesicles from brain and kidney, a tissue that
contains Glc 6-P phosphatase, demonstrate the reliability of using the
processing glucosidase activities as latency markers for topological
studies with microsomal vesicles from non-gluconeogenic tissues lacking Glc
6-P phosphatase. The results obtained from the trypsin-sensitivity assays
with sealed microsomal vesicles from brain are consistent with a
topological model in which Glc-P-Dol is synthesized on the cytoplasmic face
of the ER, and subsequently utilized by the three Glc-P-Dol-mediated
GlcTases after "flip-flopping" to the lumenal monolayer.
相似文献
74.
75.
76.
Isolated populations of drosophila pseudoobscura, separated from North
American populations by about 2,400 km, were found in Colombia in 1960. We
compared for sequences of the small ribosomal RNA (srRNA) gene on the
mitochondria between North American and Colombian D. pseudoobscura in order
to clarify the age of the Colombian isolates. The North American
populations were not genetically different from each other but were
genetically different from the Colombian populations. The Mexican strains
represent the area from which the Colombian founders might have come. The
estimated net nucleotide divergence between Mexican and Colombian D.
pseudoobscura indicates that the Colombian population is not an ancient
lineage. Phylogenies using both distance and parsimony methodologies
reinforced this conclusion. The Colombian samples group together with both
methods but, according to the bootstrap analysis, not significantly. It
appears that the populations have not been separated long enough for their
DNA sequences to show much divergence.
相似文献
77.
Julia S Bennett Keith A Jolley PFrederick Sparling Nigel J Saunders CAnthony Hart Ian M Feavers Martin CJ Maiden 《BMC biology》2007,5(1):35
Background
Various typing methods have been developed for Neisseria gonorrhoeae, but none provide the combination of discrimination, reproducibility, portability, and genetic inference that allows the analysis of all aspects of the epidemiology of this pathogen from a single data set. Multilocus sequence typing (MLST) has been used successfully to characterize the related organisms Neisseria meningitidis and Neisseria lactamica. Here, the same seven locus Neisseria scheme was used to characterize a diverse collection of N. gonorrhoeae isolates to investigate whether this method would allow differentiation among isolates, and to distinguish these three species. 相似文献78.
Will Van Treuren Loganathan Ponnusamy R. Jory Brinkerhoff Antonio Gonzalez Christian M. Parobek Jonathan J. Juliano Theodore G. Andreadis Richard C. Falco Lorenza Beati Ziegler Nicholas Hathaway Corinna Keeler Michael Emch Jeffrey A. Bailey R. Michael Roe Charles S. Apperson Rob Knight Steven R. Meshnick 《Applied and environmental microbiology》2015,81(18):6200-6209
Ixodes scapularis is the principal vector of Lyme disease on the East Coast and in the upper Midwest regions of the United States, yet the tick is also present in the Southeast, where Lyme disease is absent or rare. A closely related species, I. affinis, also carries the pathogen in the South but does not seem to transmit it to humans. In order to better understand the geographic diversity of the tick, we analyzed the microbiota of 104 adult I. scapularis and 13 adult I. affinis ticks captured in 19 locations in South Carolina, North Carolina, Virginia, Connecticut, and New York. Initially, ticks from 4 sites were analyzed by 454 pyrosequencing. Subsequently, ticks from these sites plus 15 others were analyzed by sequencing with an Illumina MiSeq machine. By both analyses, the microbiomes of female ticks were significantly less diverse than those of male ticks. The dissimilarity between tick microbiomes increased with distance between sites, and the state in which a tick was collected could be inferred from its microbiota. The genus Rickettsia was prominent in all locations. Borrelia was also present in most locations and was present at especially high levels in one site in western Virginia. In contrast, members of the family Enterobacteriaceae were very common in North Carolina I. scapularis ticks but uncommon in I. scapularis ticks from other sites and in North Carolina I. affinis ticks. These data suggest substantial variations in the Ixodes microbiota in association with geography, species, and sex. 相似文献
79.
Complement proteins in blood recognize charged particles. The anionic phospholipid (aPL) cardiolipin binds both complement proteins C1q and factor H. C1q is an activator of the complement classical pathway, while factor H is an inhibitor of the alternative pathway. To examine opposing effects of C1q and factor H on complement activation by aPL, we surveyed C1q and factor H binding, and complement activation by aPL, either coated on microtitre plates or in liposomes. Both C1q and factor H bound to all aPL tested, and competed directly with each other for binding. All the aPL activated the complement classical pathway, but negligibly the alternative pathway, consistent with accepted roles of C1q and factor H. However, in this system, factor H, by competing directly with C1q for binding to aPL, acts as a direct regulator of the complement classical pathway. This regulatory mechanism is distinct from its action on the alternative pathway. Regulation of classical pathway activation by factor H was confirmed by measuring C4 activation by aPL in human sera in which the C1q:factor H molar ratio was adjusted over a wide range. Thus factor H, which is regarded as a down-regulator only of the alternative pathway, has a distinct role in downregulating activation of the classical complement pathway by aPL. A factor H homologue, β2-glycoprotein-1, also strongly inhibits C1q binding to cardiolipin. Recombinant globular domains of C1q A, B and C chains bound aPL similarly to native C1q, confirming that C1q binds aPL via its globular heads. 相似文献
80.
Gut microbial ecology of lizards: insights into diversity in the wild,effects of captivity,variation across gut regions and transmission 下载免费PDF全文
Kevin D. Kohl Antonio Brun Melisa Magallanes Joshua Brinkerhoff Alejandro Laspiur Juan Carlos Acosta Enrique Caviedes‐Vidal Seth R. Bordenstein 《Molecular ecology》2017,26(4):1175-1189
Animals maintain complex associations with a diverse microbiota living in their guts. Our understanding of the ecology of these associations is extremely limited in reptiles. Here, we report an in‐depth study into the microbial ecology of gut communities in three syntopic and viviparous lizard species (two omnivores: Liolaemus parvus and Liolaemus ruibali and an herbivore: Phymaturus williamsi). Using 16S rRNA gene sequencing to inventory various bacterial communities, we elucidate four major findings: (i) closely related lizard species harbour distinct gut bacterial microbiota that remain distinguishable in captivity; a considerable portion of gut bacterial diversity (39.1%) in nature overlap with that found on plant material, (ii) captivity changes bacterial community composition, although host‐specific communities are retained, (iii) faecal samples are largely representative of the hindgut bacterial community and thus represent acceptable sources for nondestructive sampling, and (iv) lizards born in captivity and separated from their mothers within 24 h shared 34.3% of their gut bacterial diversity with their mothers, suggestive of maternal or environmental transmission. Each of these findings represents the first time such a topic has been investigated in lizard hosts. Taken together, our findings provide a foundation for comparative analyses of the faecal and gastrointestinal microbiota of reptile hosts. 相似文献