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11.
Renato V. La Rocca Cy A. Stein Romano Danesi Charles E. Myers 《The Journal of steroid biochemistry and molecular biology》1990,37(6):893-898
Suramin, a polyanionic compound originally synthesized for use as an antiparasitic agent, has recently entered clinical trials for the treatment of a variety of human cancers refractory to conventional modalities of therapy. This is based on suramin's ability to bind and to inactivate growth factor and enzyme systems critical to cellular homeostasis and proliferation. In addition, this compound possesses adrenocorticolytic properties in vivo and exerts significant cytostatic and cytocidal effects against a variety of human tumor cell lines in vitro. Pilot studies using suramin have thus far been conducted in adrenocortical carcinoma, prostate cancer refractory to conventional hormonal manipulation and nodular lymphomas. 相似文献
12.
Arsenio Corrado Negrini Renato Ariano Guiseppina Delbono Antonio Ebbli Antonio Quaglia Daniele Arobba 《Aerobiologia》1992,8(3):355-358
Summary The authors examined 734 sensitised patients living in four localities in Liguria (Genoa, Savona, Pietra Ligure and Sanremo). The commonest source of sensitisation (62.7%) was Urticaceae (Parietaria), followed by Poaceae (52.5%) andOlea europaea L. (24.0%). A survey of airborne pollens revealed a greater presence of Urticaceae and Poaceae in Genoa and of Oleaceae in Pietra Ligure and Sanremo. 相似文献
13.
Piero Pollesello Renato Toffanin Erminio Murano Roberto Rizzo Sergio Paoletti Bjarne J. Kvam 《Journal of applied phycology》1992,4(2):149-155
Lipid extracts of the red algaGracilaria longa were studied by1H- and13C-NMR spectroscopy. Peaks in the13C-NMR spectra attributable to sterols, chlorophylls and carotenoids allowed free and acylated cholesterol, chlorophylla and lutein to be identified as the most abundant components of these classes. A content of 0.5 ± 0.1 μmoles of total cholesterol/g
wet alga was estimated from the1H-NMR spectrum, which also allowed the determination of the phosphatidylcholine/total lipid molar ratio (9.5 ± 0.5%). The13C-NMR spectroscopic experiments provided information on the position of the double bonds on the fatty acid residues. A comparison
between NMR spectra of lipid extracts obtained for wet and dried alga showed that the alga undergoes both a dramatic peroxidation
and some glycolipid degradation during the drying process. 相似文献
14.
Carole L. Banka Michael W. Unger Renato Dulbecco Gregory F. Erickson 《Molecular reproduction and development》1986,13(1):29-38
Cell surface antigenic changes associated with differentiation of the rat oocyte and early embryo have been demonstrated with a monoclonal antibody (anti-OA-1). Antigen is first detectable coincident with initiation of oocyte growth, is a constant feature of all growing oocytes and displays a redistribution during meiotic maturation. Following fertilization, antigen is detectable on the surface of the embryo through the four-cell stage. This first monospecific marker for the rat oocyte and embryo should prove useful in probing structure/function relationships in oocyte growth, meiotic maturation fertilization, and/or early embryonic development. 相似文献
15.
Agglutinating activity of gliadin-derived peptides from bread wheat: implications for coeliac disease pathogenesis 总被引:1,自引:0,他引:1
S Auricchio G De Ritis M De Vincenzi E Mancini M Minetti O Sapora V Silano 《Biochemical and biophysical research communications》1984,121(2):428-433
The PT-digest of bread wheat gliadin was very active in agglutinating undifferentiated human K562(S) cells. This activity was quantitatively, but not qualitatively, similar to that of Con A or WGA. Moreover, Con A-induced cell agglutination was inhibited by mannan and mannose, WGA-induced agglutination by NAG only, and cell agglutination induced by bread wheat gliadin peptides was inhibited by each of these three saccharides. Not only was mannan the most active saccharide in preventing cell agglutination induced by bread wheat gliadin peptides, but it was also able to dissociate agglutinated cells. As compared to the PT- digest of whole bread wheat gliadin, the digest obtained from purified A-gliadin was tenfold more active. The PT-digest of durum wheat gliadin did not show any agglutinating activity. 相似文献
16.
Mire vegetation in the Apuanian Alps (N Italy) is analyzed from the phytosociological and the synecological points of view. Three vegetation types are delimited by numerical methods and compared with mire communities of the Alps and the Apennines. Furthermore, a chorological evaluation of this vegetation is attempted on a floristical basis. 相似文献
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Acid-soluble nucleotides of pinto bean leaves at different stages of development 总被引:4,自引:3,他引:1 下载免费PDF全文
Acid-soluble nucleotides of unifoliate leaves of Pinto bean plants (Phaseolus vulgaris L.) were determined at young, mature, and senescent stages of development. At least 25 components could be distinguished on the basis of inorganic phosphorus determinations and 37 or more fractions on the basis of 32P labeling, with adenosine di- and triphosphates accounting for 60% of the total moles of nucleotide. The total nucleotide P and inorganic P, on a fresh weight basis, decreased about 44% between each stage of leaf development, but decrements in the levels of individual nucleotides varied from this over-all pattern. 相似文献
20.
Summary In the brain of the cockroach Periplaneta americana, the beta lobes of the corpora pedunculata respond with an intense positive reaction to a specific fluorescence histochemical method for catecholamines. The fluorescence reaction disappears completely after prolonged treatment of the cockroaches with reserpine. An ultrastructural examination of the beta lobes in formaldehyde-glutaraldehyde-osmium fixed preparations reveals the presence of two types of fibres: 1) Fibres and nerve endings containing small clear vesicles and sligthly larger vesicles with a semi-dense content. The appearance and size distribution of these vesicles ist not affected by treatment with reserpine. 2) Fibres containing larger and denser vesicles, but practically no clear vesicles. The size distribution of these dense vesicles is only slightly affected by treatment of the cockroaches with reserpine.If brain slices are incubated in a medium containing noradrenaline or -methyl-noradrenaline and fixed in permanganate, small vesicles with electron-dense central cores show up, similar to those which have been described in vertebrate adrenergic nerve fibres (small granular vesicles). They are confined to one of the two types of fibres (a and b) visible in these preparations, namely to type b, whose correspondence with type 2 fibres of formaldehyde-glutaraldehyde-osmium fixed preparations is discussed.The authors wish to thank Mr. E. Chessa and Mr. F. Piccirilli for technical assistance in photography. 相似文献