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排序方式: 共有141条查询结果,搜索用时 15 毫秒
11.
Role of erythropoietin in adaptation to hypoxia 总被引:3,自引:0,他引:3
12.
Š. Bauer O. Bauerová L. Masler D. Šikl 《Cellular and molecular life sciences : CMLS》1962,18(10):441-441
Summary By application of the counter-current method on extracts ofErysimum canescens Roth, four new crystalline glycosides have been isolated besides of Helveticoside and Erysimoside. The structure of one of them, named Erycanoside, has been determined as Strophanthidin--2-desoxy-D-glucosido-glucoside. 相似文献
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Zusammenfassung Der elektrische FischGnathonemus petersii sendet beim Angriff auf einen anderen Mormyriden,Mormyrus rume, und während des Breitseitimponierens «burst»-artige elektrische Entladungen von Frequenzen bis zu 140 Hz aus.
This study was sponsored by a fellowship and by research grant No 318/3b of the Deutsche Forschungsgemeinschaft. I am especially endebted to Dr.T. Szabo for his support, his helpful discussions and for his critical comments during the experiments. 相似文献
This study was sponsored by a fellowship and by research grant No 318/3b of the Deutsche Forschungsgemeinschaft. I am especially endebted to Dr.T. Szabo for his support, his helpful discussions and for his critical comments during the experiments. 相似文献
15.
Summary By means of ahaemo-agglutination test using erythrocytes sensitised with tannic acid, we were able to demonstrate the presence of cow's milk antibodies in humans. The use of the haemo-agglutination test enables us now to give exact information on the titer value of the antibody in human serum. Previously this was limitately possible using the method of antibody demonstration by means of the complement-compound reaction.We have well-established reasons to assume that other antibodies caused by various antigens, can be determined by means of the haemo-agglutination test. 相似文献
16.
Alexander DM Smail I Bauer FE Chapman SC Blain AW Brandt WN Ivison RJ 《Nature》2005,434(7034):738-740
The tight relationship between the masses of black holes and galaxy spheroids in nearby galaxies implies a causal connection between the growth of these two components. Optically luminous quasars host the most prodigious accreting black holes in the Universe, and can account for greater than or approximately equal to 30 per cent of the total cosmological black-hole growth. As typical quasars are not, however, undergoing intense star formation and already host massive black holes (> 10(8)M(o), where M(o) is the solar mass), there must have been an earlier pre-quasar phase when these black holes grew (mass range approximately (10(6)-10(8))M(o)). The likely signature of this earlier stage is simultaneous black-hole growth and star formation in distant (redshift z > 1; >8 billion light years away) luminous galaxies. Here we report ultra-deep X-ray observations of distant star-forming galaxies that are bright at submillimetre wavelengths. We find that the black holes in these galaxies are growing almost continuously throughout periods of intense star formation. This activity appears to be more tightly associated with these galaxies than any other coeval galaxy populations. We show that the black-hole growth from these galaxies is consistent with that expected for the pre-quasar phase. 相似文献
17.
The melanocyte differentiation program predisposes to metastasis after neoplastic transformation 总被引:1,自引:0,他引:1
Gupta PB Kuperwasser C Brunet JP Ramaswamy S Kuo WL Gray JW Naber SP Weinberg RA 《Nature genetics》2005,37(10):1047-1054
The aggressive clinical behavior of melanoma suggests that the developmental origins of melanocytes in the neural crest might be relevant to their metastatic propensity. Here we show that primary human melanocytes, transformed using a specific set of introduced genes, form melanomas that frequently metastasize to multiple secondary sites, whereas human fibroblasts and epithelial cells transformed using an identical set of genes generate primary tumors that rarely do so. Notably, these melanomas have a metastasis spectrum similar to that observed in humans with melanoma. These observations indicate that part of the metastatic proclivity of melanoma is attributable to lineage-specific factors expressed in melanocytes and not in other cell types analyzed. Analysis of microarray data from human nevi shows that the expression pattern of Slug, a master regulator of neural crest cell specification and migration, correlates with those of other genes that are important for neural crest cell migrations during development. Moreover, Slug is required for the metastasis of the transformed melanoma cells. These findings indicate that melanocyte-specific factors present before neoplastic transformation can have a pivotal role in governing melanoma progression. 相似文献
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The morphology of model complexes between colloidal gold, ferritin and anti-ferritin antibodies has been studied in order to evaluate the potential of colloidal gold as a cytochemical marker. 相似文献
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J. Mokrý I. Kompiš O. Bauerová J. Tomko Š. Bauer 《Cellular and molecular life sciences : CMLS》1961,17(8):354-354
Summary The isolation of two new alkaloids fromVinca minor L. (Apocynaceae) is described. Vincarein, C21H24N2O4, and Vincanorin, C19H22N2O, both probably belong to the group of indol alkaloids. 相似文献