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Nel periodo compreso tra gennaio 1990 e gennaio 1994, 80 pazienti affetti da neoplasia del massiccio facciale e della regione cervicale, non trattati precedentemente, sono stati sottoposti consecutivamente ad esame TC e RM della t...
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Nel periodo compreso tra gennaio 1990 e gennaio 1994, 80 pazienti affetti da neoplasia del massiccio facciale e della regione cervicale, non trattati precedentemente, sono stati sottoposti consecutivamente ad esame TC e RM della testa e del collo; tutti i casi hanno successivamente eseguito intervento chirurgico con stadiazione istopatologica. I risultati della valutazione TC e della RM sono stati confrontati tra loro e con la stadiazione istologica. Quarantotto su 52 casi T4 alla TC (89%) sono stati confermati dall'esame istopatologico postoperatorio; 7 su 13 T3 all'esame TC (54%) sono risultati alla chirurgia pT3 ed infine 8 su 15 (53%) T2 all'esame tomodensitometrico sono stati valutati pT2 all'esame istologico. La TC ha sovrastadiato 4 casi (T4) definiti all'esame istopatologico 2 pT2 e 2 pT3. Tutti i 54 casi T4 alla RM (100%) sono stati confermati dall'esame istologico. Dei 12 pazienti giudicati T3, 3 (25%) hanno subito una variazione del parametro «T» in seguito alla verifica istologica in quanto risultati pT4; infine, 4 dei 14 casi giudicati T2 (28%) sono risultati sottostadiati in quanto pT4 all'esame istologico definitivo. Un solo paziente, pT4 alla chirurgia ed alla TC, è stato giudicato erroneamente T3 dalla RM in quanto presentava infiltrazione dell'osso ioide non evidente all'esame RM, mentre in 6 casi la RM ha modificato correttamente la stadiazione del parametro «T» della TC. L'accuratezza globale dei due esami è stata del 79% e del 91% rispettivamente per la TC e la RM. I risultati della valutazione TC ed RM del parametro «N» sono i seguenti: sensibilità 70% contro 75%, specificità 80% contro 78% e accuratezza 75% contro il 76%. In solo due pazienti la RM ha determinato il corretto coinvolgimento linfonodale (stadio: N1, confermato dalla chirurgia) rispetto alla TC.
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South Andean Loasas (Blumenbachia, Caiophora, Loasa, Scyphanthus) are a monophyletic group of taxa within Loasaceae subfam. Loasoideae, comprising some 100 species, 49 of which are investigated here. They retain a many-layered tes...
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South Andean Loasas (Blumenbachia, Caiophora, Loasa, Scyphanthus) are a monophyletic group of taxa within Loasaceae subfam. Loasoideae, comprising some 100 species, 49 of which are investigated here. They retain a many-layered testa in the mature seeds and usually have passive transfer testas with complex, spongiose wall outgrowths. Additional modifications concern the undulations of the testa epidermis, presence or absence of the outer periclinal wall, secondary sculpturing, the presence or absence of spines, warts and finally spongiose structures on the anticlinal walls of the testa epidermis and the inner periclinal wall. Seeds of the widespread "deeply pitted" type are plesiomorphic, while various subclades of South Andean Loasas have derivations underscoring their relationships and confirming the relationships found with molecular markers and other morphological characters. The genus Blumenbachia has either seeds with a many-layered testa forming longitudinal lamellae (sect. Angulatae), or balloon seeds with a loose outer testa layer and spongiose wall outgrowths on the inner periclinal walls (sect. Blumenbachia and sect. Gripidea) and is clearly monophyletic. Loasa s.str. (ser. Loasa, ser. Macrospermae, ser. Floribundae, ser. Deserticolae) is characterized by the presence of a subterminal hilum or hilar scar and one subgroup (ser. Loasa, ser. Macrospermae) by very large and heavy seeds with a collapsed testa. L. ser. Pinnatae, ser. Acaules, ser. Volubiles, Scyphanthus and Caiophora share more or less one seed types with minor modifications. Within Caiophora various derivations are observed, of which the gradual loss of the secondary sculpture of the inner periclinal wall is the most striking one. Anemochoria is the most widespread dispersal mechanism in South Andean Loasas and is achieved in at least five structurally different ways. (c) 2005 Elsevier GmbH. All rights reserved.
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Using random amplified polymorphic DNA (RAPD), amplified fragment length polymorphism (AFLP), simple sequence repeats (SSR), and morphological traits, the first genetic maps for Cucurbita pepo (2n=2x=40) were constructed and compa...
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Using random amplified polymorphic DNA (RAPD), amplified fragment length polymorphism (AFLP), simple sequence repeats (SSR), and morphological traits, the first genetic maps for Cucurbita pepo (2n=2x=40) were constructed and compared. The two mapping populations consisted of 92 F individuals each. One map was developed from a cross between an oil-seed pumpkin breeding line and a zucchini accession, into which genes for resistance to Zucchini Yellow Mosaic Virus (ZYMV) from a related species, C. moschata, had been introgressed. The other map was developed from a cross between an oil-seed pumpkin and a crookneck variety. A total of 332 and 323 markers were mapped in the two populations. Markers were distributed in each map over 21 linkage groups and covered an average of 2,200 cM of the C. pepo genome. The two maps had 62 loci in common, which enabled identification of 14 homologous linkage groups. Polyacrylamide gel analyses allowed detection of a high number of markers suitable for mapping, 10% of which were co-dominant RAPD loci. In the Pumpkin-Zucchini population, bulked segregant analysis (BSA) identified seven markers less than 7 cM distant from the locus n, affecting lignification of the seed coat. One of these markers, linked to the recessive hull-less allele (AW11-420), was also found in the Pumpkin-Crookneck population, 4 cM from n. In the Pumpkin-Zucchini population, 24 RAPD markers, previously introduced into C. pepo from C. moschata, were mapped in two linkage groups (13 and 11 markers in LGpz1 and LGpz2, respectively), together with two sequence characterized amplified region (SCAR) markers linked to genes for resistance to ZYMV.
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Fatty acids (FAs) and FA-derived complex lipids play important roles in plant growth and vegetative development and are a class of prominent metabolites stored in mature seeds. The factors and regulatory networks that control FA a...
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Fatty acids (FAs) and FA-derived complex lipids play important roles in plant growth and vegetative development and are a class of prominent metabolites stored in mature seeds. The factors and regulatory networks that control FA accumulation in plant seeds remain largely unknown. The role of TRANSPARENT TESTA8 (TT8) in the regulation of flavonoid biosynthesis and the formation of seed coat color is extensively studied; however, its function in affecting seed FA biosynthesis is poorly understood. In this article, we show that Arabidopsis (Arabidopsis thaliana) TT8 acts maternally to affect seed FA biosynthesis and inhibits seed FA accumulation by down-regulating a group of genes either critical to embryonic development or important in the FA biosynthesis pathway. Moreover, the tt8 mutation resulted in reduced deposition of protein in seeds during maturation. Posttranslational activation of a TT8-GLUCOCORTICOID RECEPTOR fusion protein and chromatin immunoprecipitation assays demonstrated that TT8 represses the activities of LEAFY COTYLEDON1, LEAFY COTYLEDON2, and FUSCA3, the critical transcriptional factors important for seed development, as well as CYTIDINEDIPHOSPHATE DIACYLGLYCEROL SYNTHASE2, which mediates glycerolipid biosynthesis. These results help us to understand the entire function of TT8 and increase our knowledge of the complicated networks regulating the formation of FA-derived complex lipids in plant seeds.
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This study aimed to test the reliability and validity of a Norwegian measure of adolescentsa?? intentions to be physically active after graduation (the Intention to be Physically Active After Graduation [IPAG] Questionnaire). The ...
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This study aimed to test the reliability and validity of a Norwegian measure of adolescentsa?? intentions to be physically active after graduation (the Intention to be Physically Active After Graduation [IPAG] Questionnaire). The development of IPAG involved a translation and back-translation procedure and a testa??retest study, performed on 105 adolescents (M age = 17.1, SD = 0.6) from three different high schools in Kristiansand, Norway. The four IPAG items loaded on one single factor, demonstrating acceptable factor loadings (.68-.90) and acceptable Cronbacha??s alpha values (.84 and .84) in both the test and retest assessment. IPAG correlated positively with a measure of attitudes toward physical activity (.61-.71) and a measure of participantsa?? intentions to be physically active next month (.77-.82), supporting both construct validity and criterion-related validity of the IPAG-Questionnaire. Acceptable reliability and validity of IPAG was found, which supports the use of this instrument in future research.
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During Arabidopsis seed development large quantities of mucilage, composed of pectins, are deposited into the apoplast underneath the outer wall of the seed coat. Upon imbibition of mature seeds, the stored mucilage expands throug...
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During Arabidopsis seed development large quantities of mucilage, composed of pectins, are deposited into the apoplast underneath the outer wall of the seed coat. Upon imbibition of mature seeds, the stored mucilage expands through hydration and breaks the outer cell wall that encapsulates the whole seed. Mutant seeds carrying loss-of-function alleles of AtSBT1.7 that encodes one of 56 Arabidopsis thaliana subtilisin-like serine proteases (subtilases) do not release mucilage upon hydration. Microscopic analysis of the mutant seed coat revealed no visible structural differences compared with wild-type seeds. Weakening of the outer primary wall using cation chelators triggered mucilage release from the seed coats of mutants. However, in contrast to mature wild-type seeds, the mutant's outer cell walls did not rupture at the radial walls of the seed coat epidermal cells, but instead opened at the chalazal end of the seed, and were released in one piece. In atsbt1.7, the total rhamnose and galacturonic acid contents, representing the backbone of mucilage, remained unchanged compared with wild-type seeds. Thus, extrusion and solubility, but not the initial deposition of mucilage, are affected in atsbt1.7 mutants. AtSBT1.7 is localized in the developing seed coat, indicating a role in testa development or maturation. The altered mode of rupture of the outer seed coat wall and mucilage release indicate that AtSBT1.7 triggers the accumulation, and/or activation, of cell wall modifying enzymes necessary either for the loosening of the outer primary cell wall, or to facilitate swelling of the mucilage, as indicated by elevated pectin methylesterase activity in developing atsbt1.7 mutant seeds.
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It is becoming increasingly vital to improve the yield of seed crops to feed an expanding population and, more recently, for biofuel production. One strategy to increase the yield is to increase the seed size, provided that there ...
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It is becoming increasingly vital to improve the yield of seed crops to feed an expanding population and, more recently, for biofuel production. One strategy to increase the yield is to increase the seed size, provided that there is not a concomitant decrease in seed number. In a previous study, we described a mutant in the AUXIN RESPONSE FACTOR 2 (ARF2) gene which produced extra cells in the seed coat and, subsequently, enlarged seeds. However, arf2 mutant plants also show severely reduced self-fertility caused, in part, by over-elongated sepals that prevent flower opening. As a low seed set increases individual seed size, a meaningful comparison of the yield in arf2 and wild-type plants could not be conducted. In this study, we show that targeted expression of wild-type ARF2 in the sepals and petals of arf2-9 mutant flowers restores flower opening and dramatically increases seed set. The restored plants retain both enlarged integuments and increased seed size, reinforcing previous evidence that arf2 mutations increase seed weight through their effect on integuments and not only via reduced fertility. We also show that the measurement of the harvest index in Arabidopsis is useful in assessing the impact of introduced traits on the yield.
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Seed morphology of Calluna vulgaris was studied. Seeds were collected and stored under cold and dry conditions. Scanning electron microscopy pictures were taken for whole seeds and details. Measures were made for different quantit...
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Seed morphology of Calluna vulgaris was studied. Seeds were collected and stored under cold and dry conditions. Scanning electron microscopy pictures were taken for whole seeds and details. Measures were made for different quantitative characters. A complete description is given. Seeds are tiny (0.55-0.65 mm), ellipsoid and with a reticulated pattern for testa sculpture, with the hilum region transformed into a pore. This character clearly distinguish Calluna seeds from those of Erica.
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An experiment was conducted in Etna, Sicily, Italy, to conserve and increase the value of the best native chestnut trees from 43 genotypes for fruit production. Fruit ripening occurred between the last week of September and the se...
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An experiment was conducted in Etna, Sicily, Italy, to conserve and increase the value of the best native chestnut trees from 43 genotypes for fruit production. Fruit ripening occurred between the last week of September and the second week of November. The husk traits were also observed. The valves were completely opened in 50% of genotypes, closed in 23% of genotypes and 14% were semi-open while the remaining genotypes (13%) did not show a particular tendency. The number of normal fruits inside the husk was 0.9 and 2.8. Fruit shape and size showed great variability in terms of length, from 23.5 to 39.1 mm, weight from 23.2 to 35.5 mm, and thickness from 14.4 to 23.6 mm. The number of fruits per kg ranged from 72 to 219. Of the samples studied, 35% presented a globose shape and 28% an ovoid shape. Testa removal was medium-weak for 35% of the genotypes, whereas 33% of the genotypes had a value of penetration of testa into embryo between 1 and 10. Thirty-five percent of the samples had a weak degree of penetration. Nut colour at harvesting was reddish brown-blackish brown in 23% of genotypes. Skin brightness was present for 37% of genotypes..
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