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Earthquake-collapsed building identification is important in earthquake damage assessment and is evidence for mapping seismic intensity. After the May 12th Wenchuan major earthquake occurred, experts from CEODE and IPSC collaborated to make a rapid earthquake damage assessment. A crucial task was to identify collapsed buildings from ADS40 images in the earthquake region. The difficulty was to differentiate collapsed buildings from concrete bridges, dry gravels, and landslide-induced rolling stones since they had a similar gray level range in the image. Based on the IPSC method, an improved automatic identification technique was developed and tested in the study area, a portion of Beichuan County. Final results showed that the technique's accuracy was over 95%. Procedures and results of this experiment are presented in this article. Theory of this technique indicates that it could be applied to collapsed building identification caused by other disasters.  相似文献   
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Summary The estradiol 17-synthesis by 4 pathway has been studied in homogenous cultures of Sertoli cells isolated from adult rat testes. The data reported clearly demonstrate that progesterone, androstenedione, testosterone and estrone induce an increase of the estradiol 17-production.This work was partially supported by grants No. 77.01322.04 and No. 77.01958.04 from the Consiglio Nazionale delle Ricerche.The excellent technical assistance of Antonio Muller and Massimo Rosati is deeply appreciated.  相似文献   
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Summary By means of analytical calculations, an attempt is made to approximate the profile of the human red cell during the disk-sphere transition induced by variation of the tonicity of the medium.  相似文献   
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Fixation of ejaculated spermatozoa for electron microscopy   总被引:79,自引:0,他引:79  
M Stefanini  C De Martino  L Zamboni 《Nature》1967,216(5111):173-174
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Illumination changes elicit modifications of thylakoid proteins and reorganization of the photosynthetic machinery. This involves, in the short term, phosphorylation of photosystem II (PSII) and light-harvesting (LHCII) proteins. PSII phosphorylation is thought to be relevant for PSII turnover, whereas LHCII phosphorylation is associated with the relocation of LHCII and the redistribution of excitation energy (state transitions) between photosystems. In the long term, imbalances in energy distribution between photosystems are counteracted by adjusting photosystem stoichiometry. In the green alga Chlamydomonas and the plant Arabidopsis, state transitions require the orthologous protein kinases STT7 and STN7, respectively. Here we show that in Arabidopsis a second protein kinase, STN8, is required for the quantitative phosphorylation of PSII core proteins. However, PSII activity under high-intensity light is affected only slightly in stn8 mutants, and D1 turnover is indistinguishable from the wild type, implying that reversible protein phosphorylation is not essential for PSII repair. Acclimation to changes in light quality is defective in stn7 but not in stn8 mutants, indicating that short-term and long-term photosynthetic adaptations are coupled. Therefore the phosphorylation of LHCII, or of an unknown substrate of STN7, is also crucial for the control of photosynthetic gene expression.  相似文献   
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In degenerative disorders of the central nervous system (CNS), transplantation of neural multipotent (stem) precursor cells (NPCs) is aimed at replacing damaged neural cells. Here we show that in CNS inflammation, NPCs are able to promote neuroprotection by maintaining undifferentiated features and exerting unexpected immune-like functions. In a mouse model of chronic CNS inflammation, systemically injected adult syngeneic NPCs use constitutively activated integrins and functional chemokine receptors to selectively enter the inflamed CNS. These undifferentiated cells survive repeated episodes of CNS inflammation by accumulating within perivascular areas where reactive astrocytes, inflamed endothelial cells and encephalitogenic T cells produce neurogenic and gliogenic regulators. In perivascular CNS areas, surviving adult NPCs induce apoptosis of blood-borne CNS-infiltrating encephalitogenic T cells, thus protecting against chronic neural tissue loss as well as disease-related disability. These results indicate that undifferentiated adult NPCs have relevant therapeutic potential in chronic inflammatory CNS disorders because they display immune-like functions that promote long-lasting neuroprotection.  相似文献   
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Summary The thyrotropin-releasing hormone (TRH) has been found in porcine and in bovine retina, and it is indistinguishable from synthetic TRH in its immunological and biological properties. The role of retinal TRH is unknown, it probably acts as a neurotransmitter.  相似文献   
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Contractile filaments in cells of regenerating tendon   总被引:1,自引:0,他引:1  
Summary An extensive cytoplasmic fibrillar system has been observed in fibroblast-like cells of regenerating tendon. It consists of bundles of actin filaments, which often show a cross-striated appearance due to electron dense bodies occurring throughout their length. The functional role of this contractile apparatus seems to be related to the process of movement and orientation of the newly formed cells and to the retraction of the regenerating tendon.Work was supported by grant C. N. R. n. 75.01224.04–115.5479 from Consiglio Nazionale delle Ricerche, Italy.The authors are grateful to Dr G. F. Bottazzo, Dept. Immunology, Middlesex Hospital, London, for carrying out the absorption experiments with purified actin and to Miss M. Rita Nicotra, Miss Laura M. Vassallo and Mr Mario Termine for their technical assistance.  相似文献   
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