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31.
In the past decade, the hijab has increasingly come to be regarded in the West as an unambiguous symbol of female oppression. Such an orientalist framework rests upon a feminist rhetoric using gender equality as a vehicle for the racialization of Muslims. Correlatively, from the 1970s onwards, conservative Islamist movements have converted the hijab into a natural(ized) symbol of cultural resistance to Western imperialism. In this context, what room is left to Muslim women's agency in the production of the social meanings embedded in veil wearing? I explore this issue by presenting the findings of an interview-based research with veiled and non-veiled high school Muslim female teens in Montreal (Quebec). I show that, although these teenagers have much leeway to bypass and subvert the dominant framings of veil wearing, one should not overestimate their capacity to disrupt the dominant gendered religious framework through which this practice is socially construed.  相似文献   
32.
A series of new 9-glycosyl-4,9-dihydropyrano[3,4-b]indole-1(3H)-ones 3 was synthesized in moderate to low yields. 4,9-Dihydropyrano[3,4-b]indole-1(3H)-ones (1) were coupled with different acetobromoglycopyranoses 2 in refluxing toluene in the presence of silver oxide to afford one coupling product of the respective N-glycosides. α-L-Arabinopyranosides 3j and 3m were the most active glycosides among the tested compounds against certain Gram positive and Gram negative bacterial strains.  相似文献   
33.
The TP53 gene (encoding the p53 tumor suppressor) is rarely mutated, although frequently inactivated, in medulloblastoma and ependymoma. Recent work in mouse models showed that the loss of p53 accelerated the development of medulloblastoma. The mechanism underlying p53 inactivation in human brain tumors is not completely understood. We show that ubiquitination factor E4B (UBE4B), an E3 and E4 ubiquitin ligase, physically interacts with p53 and Hdm2 (also known as Mdm2 in mice). UBE4B promotes p53 polyubiquitination and degradation and inhibits p53-dependent transactivation and apoptosis. Notably, silencing UBE4B expression impairs xenotransplanted tumor growth in a p53-dependent manner and overexpression of UBE4B correlates with decreased expression of p53 in these tumors. We also show that UBE4B overexpression is often associated with amplification of its gene in human brain tumors. Our data indicate that amplification and overexpression of UBE4B represent previously undescribed molecular mechanisms of inactivation of p53 in brain tumors.  相似文献   
34.
The peritoneal cavity (PerC) is a singular compartment where many cell populations reside and interact. Despite the widely adopted experimental approach of intraperitoneal (i.p.) inoculation, little is known about the behavior of the different cell populations within the PerC. To evaluate the dynamics of peritoneal macrophage (MØ) subsets, namely small peritoneal MØ (SPM) and large peritoneal MØ (LPM), in response to infectious stimuli, C57BL/6 mice were injected i.p. with zymosan or Trypanosoma cruzi. These conditions resulted in the marked modification of the PerC myelo-monocytic compartment characterized by the disappearance of LPM and the accumulation of SPM and monocytes. In parallel, adherent cells isolated from stimulated PerC displayed reduced staining for β-galactosidase, a biomarker for senescence. Further, the adherent cells showed increased nitric oxide (NO) and higher frequency of IL-12-producing cells in response to subsequent LPS and IFN-γ stimulation. Among myelo-monocytic cells, SPM rather than LPM or monocytes, appear to be the central effectors of the activated PerC; they display higher phagocytic activity and are the main source of IL-12. Thus, our data provide a first demonstration of the consequences of the dynamics between peritoneal MØ subpopulations by showing that substitution of LPM by a robust SPM and monocytes in response to infectious stimuli greatly improves PerC effector activity.  相似文献   
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36.
OBJECTIVE: To compare the architectural and morphometric features of pseudoepitheliomatous hyperplasia (PEH) associated with oral granular cell tumors (GCT), normal oral mucosa and oral epithelial dysplasia. STUDY DESIGN: Quantitative comparisons between the diagnostic entities were carried out at the tissue level by estimating the fractal complexity of the epithelial connective tissue interface and at the cellular level by analyzing the morphometric features of algorithmically segmented epithelial cell areas. RESULTS: Casewise multivariate analysis showed that the fractal properties produced a correct discrimination rate of 96.4% between PEH and normal mucosa. Cellular parameters gave a 100% correct discrimination rate between PEH and mild dysplasia. Combining the fractal and cellular properties also showed 100% discrimination between PEH and normal mucosa and between PEH and mild dysplasia. CONCLUSION: The results show that PEH associated with GCT displays quantifiable morphometric features that make it differentiable from normal oral mucosa and oral epithelial dysplasia.  相似文献   
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38.
In order to study interactions between microorganisms at different nutrient conditions in an arctic environment, a mesocosm experiment was performed in Kongsfjorden, Svalbard (79°N). A phytoplankton bloom was initiated by daily additions of mineral nutrients (ammonium and phosphate) to all mesocosm units. The addition of silicate and glucose, forming a factorial design (+Si/+C, +Si/−C, −Si/+C, −Si/−C), was intended to produce different types of growth rate limitation for the bacterial community. We here focus on the response in bacterial community composition to different nutrient situations. Phytoplankton, bacteria and viruses were enumerated by flow cytometry, while denaturing gradient gel electrophoresis (DGGE) was used to track changes in the bacterial community composition. Our results showed that both glucose and silicate addition affected the bacterial community composition, with the largest effect from glucose. The initial increase in bacterial abundance was most pronounced in the glucose units. After silicate addition, highest bacterial abundance was observed in the silicate treatments where mineral nutrient competition by diatoms was expected to be highest. The major effect of glucose was expressed by the significant separation of the +C and the −C samples at the end of the experiment, while silicate addition resulted in a more stable bacterial community structure. In the unit, given both silicate and glucose, the diatoms were totally outcompeted by the bacterial community. The competitive success of the heterotrophic bacteria in C-replete situations allows the conclusion that the bacteria were not more negatively affected by low temperatures than phytoplankton.  相似文献   
39.
As an introductory study of in vitro vasodilating activity, the access to the four stereomers of 1-phenylglyceryl trinitrate is described using achiral and chiral chromatography. For semi-preparative separation of the enantiomers, a Chiralcel OD (250 x 10 mm, 10 microm) was used. Catalytic reduction leading to the corresponding stereomers of 1-phenylglycerol allowed absolute configuration assignments. The same methods were used for the separation and configuration assignment of the enantiomers of 3-phenylpropane-1,2-diyl dinitrate.  相似文献   
40.
Systemic lupus erythematosus is characterized by the production of autoantibodies directed against nuclear Ags, including nucleosome and DNA. TLR9 is thought to play a role in the production of these autoantibodies through the capacity of nuclear immunogenic particles to interact both with BCR and TLR9. To determine the role of TLR9 in SLE, C57BL/6-lpr/lpr-TLR9(-/-) and TLR9(+/+) mice were analyzed. The abrogation of TLR9 totally impaired the production of anti-nucleosome Abs, whereas no difference was observed in the frequency of anti-dsDNA autoantibodies whose titer was strikingly higher in TLR9(-/-) mice. In addition a higher rate of mesangial proliferation was observed in the kidney of TLR9-deficient animals. These results indicate that in C57BL/6-lpr/lpr mice, TLR9 is absolutely required for the anti-nucleosome Ab response but not for anti-dsDNA Ab production which is involved in mesangial proliferation.  相似文献   
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