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排序方式: 共有245条查询结果,搜索用时 19 毫秒
1.
Sally Engle Merry 《American anthropologist》2001,103(1):16-29
The new urban social order depends on a complex combination of systems of punishment, discipline, and security. Scholars drawing on Foucault's analysis of the art and rationality of governance, or govemmentality, have explored how urban social orders are increasingly based on the governance of space rather than on the discipline of offenders or the punishment of offenses. The new urban social order is characterized by privatized security systems and consumer-policed spaces such as malls. Gender violence interventions represent another deployment of spatial forms of govemmentality. Over the last two decades, punishment of batterers has been augmented by disciplinary systems that teach batterers new forms of masculinity and by security systems for women based on spatial separation. In the postmodern city, spatial govemmentality is integrally connected with punishment and discipline. These new forms of governance circulate globally along with neoliberal ideas of the diminished state, [gender violence, govemmentality, urban society, globalization, law] 相似文献
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M J Engle M Dooley D J Brown 《Biochemical and biophysical research communications》1987,145(1):397-401
Fetal rabbit lungs from 23 day gestation animals were used to investigate the potential role of lactate as a substrate for fetal lung glycogen synthesis. Fetal lactate dehydrogenase activity was approximately twice that found in the adult lung, while the activity of phosphoenolpyruvate carboxykinase was elevated fourfold over the adult value. Pyruvate carboxylase activities were similar in both fetal and adult lungs. Studies employing fetal lung explants in organ culture indicated that the presence of both glucose and lactate may be necessary for glycogen accumulation in the developing fetal lung. These data support the hypothesis that lactate is an important precursor for fetal lung glycogen. 相似文献
3.
Ultraviolet Radiation Effects on Ehrlich Ascites Tumor Cells : Observations Using a Flying Spot Ultraviolet Microscope 总被引:1,自引:1,他引:0
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Jerome J. Freed James L. Engle George T. Rudkin Jack Schultz 《The Journal of cell biology》1959,5(2):205-215
A flying spot ultraviolet microscope, employing a fast scan and pulsed operation of the raster, has been used to induce radiation damage in ascites tumor slide cultures, and to study by time-lapse cinematography the progressive stages of cell damage. The cells observed came from a strain (EF7) of the Ehrlich ascites carcinoma. Irradiated cells were found to show a characteristic syndrome of damage, involving blebbing at the cell surface, while control cells in the adjacent areas of the preparation remained unchanged. The end of the blebbing period is marked by swelling of the cells, and the time taken for this phenomenon to occur was used as a measure of the severity of the damage. It was found that the time required for swelling is dependent on the size of the dose employed, as well as on the sensitivity of the cells. This latter sensitivity was found to decline as the physiological age of the tumor increased. If ultraviolet illumination below 255 mµ is excluded, no symptoms of damage occur, even when very large doses are used. These observations are discussed in relation to the nature of the system in the cell which is affected. 相似文献
4.
Sayan Mukherjee Pablo Tamayo Simon Rogers Ryan Rifkin Anna Engle Colin Campbell Todd R Golub Jill P Mesirov 《Journal of computational biology》2003,10(2):119-142
A statistical methodology for estimating dataset size requirements for classifying microarray data using learning curves is introduced. The goal is to use existing classification results to estimate dataset size requirements for future classification experiments and to evaluate the gain in accuracy and significance of classifiers built with additional data. The method is based on fitting inverse power-law models to construct empirical learning curves. It also includes a permutation test procedure to assess the statistical significance of classification performance for a given dataset size. This procedure is applied to several molecular classification problems representing a broad spectrum of levels of complexity. 相似文献
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Both oxolinic acid and coumermycin A1, inhibitors of DNA gyrase, block DNA synthesis in Escherichia coli. At low concentrations of oxolinic acid, the rate of bacterial DNA synthesis first declines rapidly but then gradually increases. This gradual increase in synthesis rate depended on the presence of wild-type recA and lexA genes; mutations in either gene blocked the increase in synthesis rate. In such mutants, oxolinic acid caused a rapid decline, followed by a slow, further decrease in DNA synthesis rate. Coumermycin A1, however, produced a more gradual decline in synthesis rate which is unaffected by defects in the recA or lexA genes. An additional difference between the two drugs was observed in a dnaA mutant, in which initiation of replication is temperature sensitive. Low concentrations of oxolinic acid, but not coumermycin A1, reduced thermal inhibition of DNA synthesis rate. 相似文献
7.
Previous reports have suggested the possibility of extensive structural homology between human erythrocyte bisphosphoglycerate synthase (glycerate-1,3-P2 leads to glycerate-2,3-P2) and phosphoglycerate mutase (glycerate-3-P in equilibrium glycerate-2-P). This study lends credence to that conjecture through comparative physicochemical investigations involving peptide mapping, circular dichroism, and immunological techniques. The data indicate that despite differences in function, both enzymes apparently manifest a high degree of similarity in primary, secondary, and tertiary structure. Mapping data also indicate that each protein is comprised of two apparently identical subunits. 相似文献
8.
Surfactant protein-A (SP-A) belongs to a family of collagen-containing C-type lectins called collectins. SP-A is expressed by renal tubule epithelial cells. We investigated the distribution of SP-A in renal cell carcinomas (RCC) using immunohistochemical techniques and western blotting. We used 35 formalin fixed, paraffin embedded (FFPE) RCC tissue samples. We compared results with clinico-pathological parameters of RCC including age, sex, Fuhrman grade, tumor volume, tumor node metastasis (TNM) and clinical stage. SP-A was localized in the glomerulus and renal tubule epithelium in nontumor tissue and strong SP-A immunoreactivity was observed in tumor tissue. SP-A was expressed in the RCC tumor cells (64%) and nontumor cells (34%) in males and RCC tumor cells (90%) and nontumor cells (30%) in females. There was a significant correlation between SP-A immunoreactivity in tumor cells and gender, age, tumor diameter, Fuhrman grade and tumor diameter. Western blot analysis supported the immunohistochemical findings. We present evidence for involvement of SP-A in RCC and suggest that increased SP-A expression in RCC is associated with favorable prognosis. 相似文献
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An Invasive Grass Increases Live Fuel Proportion and Reduces Fire Spread in a Simulated Grassland 总被引:1,自引:0,他引:1
Devan Allen McGranahan David M. Engle James R. Miller Diane M. Debinski 《Ecosystems》2013,16(1):158-169
Fire is a globally important ecosystem process, and invasive grass species generally increase fire spread by increasing the fuel load and continuity of native grassland fuelbeds. We suggest that invasive grasses that are photosynthetically active, while the native plant community is dormant reduce fire spread by introducing high-moisture, live vegetation gaps in the fuelbed. We describe the invasion pattern of a high-moisture, cool-season grass, tall fescue (Schedonorus phoenix (Scop.) Holub), in tallgrass prairie, and use spatially explicit fire behavior models to simulate fire spread under several combinations of fuel load, invasion, and fire weather scenarios. Reduced fuel load and increased extent of tall fescue invasion reduced fire spread, but high wind speed and low relative humidity can partially mitigate these effects. We attribute reduced fire spread to asynchrony in the growing seasons of the exotic, cool-season grass, tall fescue, and the native, warm-season tallgrass prairie community in this model system. Reduced fire spread under low fuel load scenarios indicate that fuel load is an important factor in fire spread, especially in invaded fuel beds. These results present a novel connection between fire behavior and asynchronous phenology between invasive grasses and native plant communities in pyrogenic ecosystems. 相似文献