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排序方式: 共有117条查询结果,搜索用时 15 毫秒
61.
Ted A. Rathbun 《American journal of physical anthropology》1982,59(1):47-60
Multivariate and cluster analyses of human skeletal remains of seven regional groups and nine individual sites and periods reveal different patterns of relationships for the sexes. This complex pattern of morphological affinities probably depends on differential demographic features. 相似文献
62.
AbstractAlthough the New Zealand ground wētā (Anostostomatidae: Hemiandrus) are widespread and abundant, little has been described of their ecology and behaviour. Within the genus several lineages have evolved with ovipositors that are unusually short for this orthopteran family. Some species with this derived morphological character also exhibit maternal care of eggs and offspring. Two new species are described here, Hemiandrus maia sp. nov. and Hemiandrus electra sp. nov. Although morphologically similar with medium length ovipositors, they are not sister taxa and live at opposite ends of South Island, New Zealand. The behaviour of Hemiandrus maia sp. nov. was studied using burrow door re-construction as a key to activity patterns. Observations at night and burrow excavation during the day were used to identify features of their behaviour. Maternal care of both eggs and nymphs was observed. Hemiandrus maia sp. nov. were shown to eat fruit, invertebrates and seeds without discrimination.http://zoobank.org/urn:lsid:zoobank.org:pub:1C7EB0D2-D01B-4D3A-B643-D17813EC2084 相似文献
63.
Eduardo AVF Ramalho Jo?o LQ Silva-Filho Marina FS Cartaxo Carmelita BL Cavalcanti Moacyr JBM Rêgo Maria BM Oliveira Eduardo IC Beltr?o 《Biological research》2014,47(1)
Background
BRCA protein interacts with at least 13 different proteins that have been implicated with cancer susceptibility and loss of BRCA function is correlated to sensitivity to DNA crosslinking agents in preclinical models.Results
BRCA2 methylation frequency was 44%, p53 Pro22 allele frequency was 32% and heterozygous frequency of Arg/Pro72 genotype was 60% which could be associated as risk factor for metastasis (p = 0.046 OR = 4.190). Regarding to polymorphism of codon 249 the frequency of Arg249 allele presented 82% which was considered not statistically significant.Conclusions
There was not statistical significance to BRCA2 promoter methylation with any parameters chosen. However, our findings suggest that patients who present heterozygous genotype at codon 72 of p53 gene may have a major susceptibility to any type of metastasis and this could serve as potential auxiliary biomarker for poor prognosis. 相似文献64.
Background
Campylobacter jejuni is a gastrointestinal pathogen of humans, but part of the normal flora of poultry, and therefore grows well at the respective body temperatures of 37°C and 42°C. Proteomic studies on temperature regulation in C. jejuni strain 81–176 revealed the upregulation at 37°C of Cj0596, a predicted periplasmic chaperone that is similar to proteins involved in outer membrane protein folding and virulence in other bacteria. 相似文献65.
T L Yaksh G Ozaki D McCumber M Rathbun C Svensson S Malkmus M C Yaksh 《Journal of applied physiology》2001,90(6):2386-2402
The biphasic display of paw-flinch behavior in the rat after injection of formalin into the dorsum of the hind paw is used for the screening of anti-hyperalgesic agents. Described and characterized here is a less labor-intensive system for counting flinch activity by detecting movement of a small metal band placed on the formalin-injected paw. A signal is generated as the band breaks the electromagnetic field of a loop antenna located under the rat and processed through an algorithm that determines flinch activity using 1) amplitude, 2) zero-voltage crossing, and 3) signal duration. Flinches are summed and stored over a selected collection interval throughout the assay for later analysis. Studies have validated the measures with respect to 1) system stability over time; 2) system-to-"practiced observer" correlation on flinch detection, r2 = 0.94; 3) system variables including time of day, sex, age, and body weight; and 4) 50% effective dose values similar to those previously reported for intrathecal morphine and the NMDA antagonist MK-801. 相似文献
66.
O'Neill T Giarratani L Chen P Iyer L Lee CH Bobiak M Kanai F Zhou BB Chung JH Rathbun GA 《The Journal of biological chemistry》2002,277(18):16102-16115
Mammalian Chk1 and Chk2 are two Ser/Thr effector kinases that play critical roles in DNA damage-activated cell cycle checkpoint signaling pathways downstream of ataxia telangiectasia-mutated and ataxia telangiectasia-related. Endogenous substrates have been identified for human hCds1/Chk2 and Chk1; however, the sequences surrounding the substrate residues appear unrelated, and consensus substrate motifs for the two Ser/Thr kinases remain unknown. We have utilized peptide library analyses to develop specific, highly preferred substrate motifs for hCds1/Chk2 and Chk1. The optimal motifs are similar for both kinases and most closely resemble the previously identified Chk1 and hCds1/Chk2 substrate target sequences in Cdc25C and Cdc25A, the regulation of which plays an important role in S and G(2)M arrest. Essential residues required for the definition of the optimal motifs were also identified. Utilization of the peptides to assay the substrate specificities and catalytic activities of Chk1 and hCds1/Chk2 revealed substantial differences between the two Ser/Thr kinases. Structural modeling analyses of the peptides into the Chk1 catalytic cleft were consistent with Chk1 kinase assays defining substrate suitability. The library-derived substrate preferences were applied in a genome-wide search program, revealing novel targets that might serve as substrates for hCds1/Chk2 or Chk1 kinase activity. 相似文献
67.
The teleost pineal organ contains functional photoreceptors that synapse with pinealofugal neurons. This study examined the effects of environmental lighting on protein content and levels of putative amino acid transmitters, as well as structural components associated with protein synthesis and neurotransmission. Goldfish subjected to continual illumination for 3 days tended to have increased pineal levels of free amino acids and protein compared to dark adapted glands. Similar responses to environmental lighting occurred in cultured glands suggesting a functional relationship to photosensory mechanisms. Morphometric ultrastructural analyses of pineal photoreceptors showed an increased size of nucleoli (especially the fibrillar component), Golgi bodies, and synaptic ribbons when glands were subjected to continuous light both in vivo and in vitro. The good agreement between protein levels and nucleolar morphology indicates a general effect of environmental lighting on photoreceptor protein metabolism, which may be related to photoreceptor outer segment renewal. Parallel changes in levels of certain amino acids (e.g., glutamate) and size of synaptic ribbons is consistent with an hypothesized role of amino acids in photoreceptor neurotransmission. 相似文献
68.
69.
Heat and mass transfer effects in static solid-substrate fermentations: design of fermentation chambers 总被引:1,自引:0,他引:1
An experimental device was constructed to allow nearly simultaneous measurements to be made on temperature and gas composition at different depths in a solid-substrate fermentation bed. The time-dependent values of temperature, mol % O(2) and mol % CO(2) were measured at five positions in beds 6.35 cm (2.5 in.) deep. With a tempeh fermentation (Rhiopus oligosporus growing on soybeans) the temperature gradient could be as steep as 3 degrees C/cm during active mold growth and concentration of CO(2) could reach 21 vol. % in the bottom layer. 相似文献
70.
Taxonomy lies at the heart of species conservation, yet many large New Zealand orthopterans remain undescribed. Among New Zealand’s anostostomatid wētā, Hemiandrus (ground wētā) is the most speciose genus but also the most poorly characterised and thus most in need of taxonomic and ecological work. Here we redescribe H. maculifrons and describe two new species of ground wētā previously encompassed by the specific name Hemiandrus maculifrons: Hemiandrus luna sp. nov. and H. brucei sp. nov. We also describe a morphologically similar and related species, Hemiandrus nox sp. nov.
http://zoobank.org/urn:lsid:zoobank.org:pub:71EA0879-A2F9-46B2-A105-E97A9AB25061
http://zoobank.org/References/71EA0879-A2F9-46B2-A105-E97A9AB25061 相似文献