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11.
12.
Jonathan H. Shannon 《American anthropologist》2003,105(2):266-277
This article examines how the performance of a variety of Islamic music in transnational cultural circuits helps to promote the idea of a style of sacred music within the category of world music. Taking as an example the performance of the mawlawiyya, or "Whirling Dervish," music and dance by a Syrian–based ensemble, I show how the idea of an authentic local Syrian sacred music tradition requires its performance globally. I use the concept of the "world stage" to examine how musical performance practices that are represented as authentic local traditions obtain both their authenticity and their local specificity through their staging in global contexts. I further explore how such musical styles as sacred and Sufi emerge as naturalized categories in world music discourse, and how processes of differentiation and commodification reconfigure both the "local" and "global." [Keywords: world music, globalization, style, Syria, Islam] 相似文献
13.
R W Leu A Q Zhou M J Kennedy B J Shannon 《Journal of immunology (Baltimore, Md. : 1950)》1991,146(4):1233-1239
Studies originally designed to assess the putative role of endogenous C5 in macrophage activation for antibody-dependent cellular cytotoxicity (ADCC) yielded unanticipated results. Resident and inflammatory peritoneal macrophages from C5-deficient AKR mice were found to have significantly lower capacity for FcR-dependent ADCC activation and phagocytosis of IgG-opsonized SRBC targets than did C5-competent C3HeB/FeJ (C3H) mice. Reconstitution of the ADCC response of AKR macrophages was accomplished initially with C5-sufficient C3H mouse serum, which suggested that endogenous C5 may be required for ADCC activation. However, further investigation largely eliminated C5 involvement in that a heat-labile component of C5-deficient AKR serum was shown to be active in the reconstitution of ADCC activation of AKR macrophages. Macrophages from AKR mice were found to have significantly lower levels of C1q mRNA synthesis, endogenous C1q levels, and C1q secretion than did C3H mouse macrophages as determined by Northern blot, Western blot, and presynthetic radiolabeling analysis, respectively. The addition of purified exogenous C1q to IgG-opsonized SRBC targets fully reconstituted ADCC activation for AKR inflammatory peritoneal macrophages to levels of normally FcR-responsive C3H macrophages. Similarly, exogenous C1q augmented FcR-dependent phagocytosis of AKR macrophages but had no effect on macrophages from responsive C3H mice. Our results indicate that AKR mice have a deficiency for FcR-dependent cellular cytotoxicity and phagocytosis that is related to their low potential for C1q synthesis and secretion rather than to their established genetic deficiency for C5 synthesis. We tentatively conclude that endogenous C1q is required as an accessory molecule for macrophage FcR-dependent effector functions and that C5 is not a prerequisite for ADCC activation. 相似文献
14.
Differences between Asn-Xaa-Thr-containing peptides: a comparison of solution conformation and substrate behavior with oligosaccharyltransferase 总被引:2,自引:0,他引:2
A series of tripeptides that satisfy the -Asn-Xaa-Thr/Ser- primary sequence requirement [Marshall, R. D. (1972) Annu. Rev. Biochem. 41, 673-702] for N-glycosylation have been synthesized and examined as potential acceptors in an oligosaccharyltransferase assay. Of these, six (Ac-Asn-Ala-Thr-NH2, Ac-Asn-Leu-Thr-NH2, Ac-Asn-Asp-Thr-NH2, Ac-Asn-D-Ala-Thr-NH2, Ac-Asn-Pro-Thr-NH2, and Ac-Asn-AIB-Thr-NH2) were examined for solution conformational properties in dimethyl sulfoxide with use of amide proton temperature coefficients, 3JHN alpha analysis [Pardi, A., et al. (1984) J. Mol. Biol. 180, 741-751], and 2-D ROESY experiments [Bothner-By, A. A., et al. (1984) J. Am. Chem. Soc. 106, 811-813]. The analysis reveals that the peptides that serve as acceptors in the transferase assay demonstrate similar conformational properties in solution. These are highlighted by a secondary structural motif that involves the interaction between the asparagine side-chain carboxamide and the backbone amide of the threonine. The peptides that show very poor acceptor, or even nonacceptor, properties in the oligosaccharyltransferase assay demonstrate different conformational features in solution. These observations may explain the distinct biological activity observed for these peptides. 相似文献
15.
Juvenile turbot,Scophthalmus maximus (L.), were exposed to 0.58 μg 1−1 Aroclor 1254 in seawater, to sediments containing 100, 60 and 1 ppm or fed with cockle containing 20 ppm PCB (polychlorinated
biphenyls). Concentration factors for liver and muscle were 104 and 103, respectively, for uptake of PCB from seawater. Contamination of muscle was similar to that of sediments containing 1 and
60 ppm PCB to which turbot were exposed, but less than the 20 ppm in their experimental diet. Contamination of flatfish in
the North Sea area is compared with the levels of PCB in the flounder,Platichthys flesus (L.), in the River Thames and predictable values for uptake of PCB from different pathways discussed. 相似文献
16.
17.
Alexander J McIntyre Charlotte Z Angel James S Smith Amy Templeman Katherine Beattie Shannon Beattie Alice Ormrod Eadaoin Devlin Charles McGreevy Chloe Bothwell Sharon
L Eddie Niamh
E Buckley Rich Williams Paul
B Mullan 《Nucleic acids research》2022,50(11):6154
Chromosome 17q23 amplification occurs in 20% of primary breast tumours and is associated with poor outcome. The TBX2 gene is located on 17q23 and is often over-expressed in this breast tumour subset. TBX2 is an anti-senescence gene, promoting cell growth and survival through repression of Tumour Suppressor Genes (TSGs), such as NDRG1 and CST6. Previously we found that TBX2 cooperates with the PRC2 complex to repress several TSGs, and that PRC2 inhibition restored NDRG1 expression to impede cellular proliferation. Here, we now identify CoREST proteins, LSD1 and ZNF217, as novel interactors of TBX2. Genetic or pharmacological targeting of CoREST emulated TBX2 loss, inducing NDRG1 expression and abolishing breast cancer growth in vitro and in vivo. Furthermore, we uncover that TBX2/CoREST targeting of NDRG1 is achieved by recruitment of TBX2 to the NDRG1 promoter by Sp1, the abolishment of which resulted in NDRG1 upregulation and diminished cancer cell proliferation. Through ChIP-seq we reveal that 30% of TBX2-bound promoters are shared with ZNF217 and identify novel targets repressed by TBX2/CoREST; of these targets a lncRNA, LINC00111, behaves as a negative regulator of cell proliferation. Overall, these data indicate that inhibition of CoREST proteins represents a promising therapeutic intervention for TBX2-addicted breast tumours. 相似文献
18.
Cultivation of Mesophilic Soil Crenarchaeotes in Enrichment Cultures from Plant Roots 总被引:2,自引:1,他引:2
Holly M. Simon Courtney E. Jahn Luke T. Bergerud Marek K. Sliwinski Paul J. Weimer David K. Willis Robert M. Goodman 《Applied microbiology》2005,71(8):4751-4760
Because archaea are generally associated with extreme environments, detection of nonthermophilic members belonging to the archaeal division Crenarchaeota over the last decade was unexpected; they are surprisingly ubiquitous and abundant in nonextreme marine and terrestrial habitats. Metabolic characterization of these nonthermophilic crenarchaeotes has been impeded by their intractability toward isolation and growth in culture. From studies employing a combination of cultivation and molecular phylogenetic techniques (PCR-single-strand conformation polymorphism, sequence analysis of 16S rRNA genes, fluorescence in situ hybridization, and real-time PCR), we present evidence here that one of the two dominant phylotypes of Crenarchaeota that colonizes the roots of tomato plants grown in soil from a Wisconsin field is selectively enriched in mixed cultures amended with root extract. Clones recovered from enrichment cultures were found to group phylogenetically with sequences from clade C1b.A1. This work corroborates and extends our recent findings, indicating that the diversity of the crenarchaeal soil assemblage is influenced by the rhizosphere and that mesophilic soil crenarchaeotes are found associated with plant roots, and provides the first evidence for growth of nonthermophilic crenarchaeotes in culture. 相似文献
19.
Prey Food Quality Affects Flagellate Ingestion Rates 总被引:1,自引:3,他引:1
Flagellate feeding efficiency appears to depend on morphological characteristics of prey such as cell size and motility, as
well as on other characteristics such as digestibility and cell surface characteristics. Bacteria of varying morphological
characteristics (cell size) and mineral nutrient characteristics or food quality (as determined by the C:N:P ratio) were obtained
by growing Pseudomonas fluorescens in chemostats at four dilution rates (0.03, 0.06, 0.10, and 0.13 h−1) and three temperatures (14°C, 20°C, and 28°C). Cells of a given food quality were heat-killed and used to grow the flagellate
Ochromonas danica. Ingestion and digestion rates were determined by using fluorescently labeled bacteria of the same food quality as the bacteria
supporting growth. Ingestion rates were affected by both food quality and cell size. Cells of high food quality (low carbon:element
ratio) were ingested at higher rates than cells of low food quality. Multiple regression analysis indicated that cell size
also influenced ingestion rate but to a much lesser extent than did food quality. Digestion rates were not correlated with
either food quality or cell size. Results suggest that flagellates may adjust feeding efficiency based on the quality of food
items available. 相似文献
20.
Significant breed differences were detected in fecal egg counts and fluke counts following experimental infection of five breeds of sheep with metacercariae of F. hepatica. Two experiments compared the responses of Barbados Blackbelly, St. Croix, Florida Native, Finn X Rambouillet and Targhee sheep to primary and challenge infections (Expt. 1) and to multiple infections (Expt. 2). Barbados Blackbelly sheep were more susceptible to infection than the other breeds in both experiments. St. Croix and Florida Native sheep were the most resistant breeds in Expt. 1, while Targhee and Florida Native were the most resistant in Expt. 2. There was no evidence of acquired immunity in any breed in either experiment. 相似文献