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排序方式: 共有398条查询结果,搜索用时 15 毫秒
391.
392.
Comparison of Coding and Spacer Region Sequences of Chromosomal rRNA-Coding Genes of Two Sequevars of Pneumocystis carinii 总被引:2,自引:0,他引:2
MARIA ORTIZ-RIVERA YONG LIU REGINA FELDER MICHAEL J. LEIBOWITZ 《The Journal of eukaryotic microbiology》1995,42(1):44-49
Two distinct sequevars, denoted Pc1 and Pc2, of the opportunistic pathogen Pneumocystis carinii have been previously identified based on the sequence of their 26S rRNA genes, the location of group I self-splicing introns and pulsed field electrophoretic patterns of chromosomal DNA. This study shows that the sequences of 16S and 5.8S rRNA genes also vary between these sequevars, and that greater variation was seen in the internal transcribed spacer regions. Polymerase chain reaction and restriction analysis can distinguish between these sequevars. 相似文献
393.
YONG LIU DAVID C. BUCK TARA A. MACEY HONGXIANG LAN KIM A. NEVE 《Journal of receptor and signal transduction research》2013,33(1):47-65
The Ca2+ sensor calmodulin (CaM) regulates numerous proteins involved in G protein-coupled receptor (GPCR) signaling. CaM binds directly to some GPCRs, including the dopamine D2 receptor. We confirmed that the third intracellular loop of the D2 receptor is a direct contact point for CaM binding using coimmunoprecipitation and a polyHis pull-down assay, and we determined that the D2-like receptor agonist 7-OH-DPAT increased the colocalization of the D2 receptor and endogenous CaM in both 293 cells and in primary neostriatal cultures. The N-terminal three or four residues of D2-IC3 were required for the binding of CaM; mutation of three of these residues in the full-length receptor (I210C/K211C/I212C) decreased the coprecipitation of the D2 receptor and CaM and also significantly decreased D2 receptor signaling, without altering the coupling of the receptor to G proteins. Taken together, these findings suggest that binding of CaM to the dopamine D2 receptor enhances D2 receptor signaling. 相似文献
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395.
YONG HOI-SEN 《Zoological Journal of the Linnean Society》1970,49(4):359-370
Rattus edwardsi ciliatus (Bonhote) and R. sabanus vociferans (Miller) are two large rats occurring in Malayan mainland forests. The allopatric taxa edwardsi and sabanus have proved difficult to distinguish by morphological characters, including external appearance and skeletal anatomy. Their taxonomic status has in fact been questioned.
The Malayan mainland forms R. edwardsi ciliatus (Bonhote) and R. sabanus vociferans (Miller) can generally be separated by body and tail coloration. Their body and skull dimensions, however, overlap considerably. Ecological data indicate that these rats exhibit habitat exclusion. Breeding and behaviour studies support this view. Karyotype and serological studies provide conclusive evidence for the distinctness as well as the close affinity of these two species. 相似文献
The Malayan mainland forms R. edwardsi ciliatus (Bonhote) and R. sabanus vociferans (Miller) can generally be separated by body and tail coloration. Their body and skull dimensions, however, overlap considerably. Ecological data indicate that these rats exhibit habitat exclusion. Breeding and behaviour studies support this view. Karyotype and serological studies provide conclusive evidence for the distinctness as well as the close affinity of these two species. 相似文献
396.
Transcriptome analysis reveals dynamic changes in the gene expression of tobacco seedlings under low potassium stress 总被引:2,自引:0,他引:2
Journal of Genetics - Potassium plays a key role in plant development and reproduction. In agricultural practice, potassium deficiency is common worldwide, and leads to crop growth inhibition and... 相似文献
397.
398.
Jin-Fang Ge Jin-Ping Qiao Cong-Cong Qi Chen-Wei Wang Jiang-Ning Zhou 《Neurochemistry international》2012
As currently understood, Alzheimer’s disease (AD) is a chronic neurodegenerative disorder that is driven by the aggregation of amyloid beta (Aβ) protein. It has been shown that resveratrol (RES) may attenuate amyloid β peptide-induced toxicity, promote Aβ clearance and reduce senile plaques. However, it remains to be determined whether RES could interact directly with Aβ. The aim of the present study was to examine the direct binding of RES to monomer and fibril Aβ. Using surface plasmon resonance (SPR) and proton nuclear magnetic resonance (1H NMR), our results identified the direct binding of RES to Aβ. The ability of RES to bind to both fibril and monomer Aβ(1–40 and 1–42) was further analyzed by SPR. The binding response of RES to fAβ(1–42) was higher than that to monomer Aβ(1–42), whereas the binding response of RES to fAβ(1–40) was lower than that to monomer Aβ(1–40). The KD of RES for fibril Aβ(1–40 or 1–42) was higher than that for the corresponding monomer Aβ. Compared to the control compound Congo red (CR), the binding responses of RES to monomer Aβ(1–42) and Aβ(1–40) were stronger, but binding to fibril Aβ(1–42) was weaker, and the KDs of RES with both monomer and fibril Aβ(1–40) and Aβ(1–42) were higher than that of CR. When Aβ(1–40 or 1–42) was co-incubated with RES (50 μM), the thioflavin T fluorescence of the mixture was weakened, and the number and length of amyloid fibrils were decreased. Furthermore, the results of staining in consecutive brain slices from AD patients showed that RES (10−4 M) could stain senile plaques. These results indicated that RES could bind directly to Aβ in different states, which may provide new insight into the protective properties of RES against AD. 相似文献