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61.
62.
Abstract New researches on the culture « in vitro » of Aucuba japonica Thunb, – Caulinar fragments grown in vitro in nutrient media solidified with agar are compared with fragments grown on a filter paper support on unshaken liquid media. Tissue cultures of Aucuba are established putting down caulinar fragments just taken from the plant with isolated callus; subcultures are obtained more easily in July. We have observed that during the months of March or April, caulinar fragments, taken from the plant at various months of the year, of different ages and cultivated on various media, unexpectedly produce many roots. 相似文献
63.
Abstract Seminal integument and germination of Cercis siliquastrum L. – A histological study of the seminal integument of Cercis siliquastrum L. has been carried out, in order to explain whether the obstacle to the germination, removed by a cold-treatment, was caused by a mechanical action of the integument itself. We have noted that both the cold-treated seeds which germinate and the non-treated control seeds which don't germinate show in the long run the same modifications. We have therefore come to the conclusion that the inability to germinate found in the non-treated seeds is not due to the mechanical resistance of the integument and we think it necessary to return to further researches, also at a biochemical level. 相似文献
64.
Prof. Carlo Cappelletti 《Plant biosystems》2013,147(2):235-240
Many members of the Orchidaceae, the largest vascular plant family in Ecuador, are at risk of extinction. It was therefore considered important to establish an efficient way of clonal propagation based on somatic embryogenesis of Cattleya maxima, a native Ecuadorian orchid. To this end, we evaluated the effect on somatic embryo induction of 12 combinations of 2,4-dichlorophenoxyacetic acid and 1-phenyl-3-(1,2,3-thiadiazol-5-yl)-urea, as well as three kinds of stresses. Protocorms produced 42% of embryogenic calli on 1/2 Murashige and Skoog (1/2 MS) medium, compared to 96.3% when protocorms were stressed for 6 h with 0.3 M NaCl, followed by cultivation on 1/2 MS medium supplemented with 0.1 mg L? 1 2,4-D. Our data demonstrated that the combination of either salt (0.3 M NaCl) or osmotic stress (0.4 M sorbitol) with subculture on 2,4-D (0.1 mg L–1) medium significantly increases the percentage of protocorms with embryogenic callus. The number of embryos per embryogenic callus was not significantly different from that obtained after subculture in growth factor-free medium. 相似文献
65.
Paola Montagnani 《Plant biosystems》2013,147(3):434-462
Summary Observations on growth and development of Salvia longistyla Benth., in several photoperiodic and termoperiodic conditions, both natural and artificial, were performed. The conclusions of my work are the following I° - It has been proved that Salvia longistyla is a typical short-day plant and that its critical point of reaction lies approssimately on the 14 hours, when the average night-temperature is about 18°C; the flowering does not succeed if the night-temperature is decidedly below 15°C. II° - The plant' requires short-day conditions not only for the formation of the flower buds, but also for the subsequent development, i. e. the full bloom; consequently the plant belongs to Eguchi's S. S. class (short day-plant for both the manifestations). III. - Under natural conditions, in our latitude, Salvia longistyla flowers only in Autumn, because only in this season we have suitable photoperiod and concomitantly suitable night-temperature. In Spring, though the day is short, the night-temperature is not sufficiently high; in Winter and in Spring, the flowering is possible only in a warm green-house, with a night-temperature of about 18°C. In orange green-houses Salvia longistyla can continue the flowering begun in Autumn; during Winter and Spring new blooms do not succeed, just because the night-temperature, in such green houses, is never sufficiently high. IV. - We can obtain fruiting only by artificial pollination (lack of natural pollination agency). V. - The basal branches do not flower even in optimal photo- and termoperiodical conditions (which allow apical flowering) on acount of a mechanism of correlative inhibition. VI. - The elongation of the internodes is relatively inhibited at a very long photoperiod, differently from what we observe in most plants. These prerogatives, verified in repeated experiments, are in perfect accordance with the characteristics of the ambient in which the plant is naturally diffused (Mexico). The altitude and latitude of the stations in which the plant has usually been found, have a short photoperiod all year long, and temperatures (also night-temperatures) costantly suitable for a good growth and bloom. The plants, in the natural ambient, are perennial and bushy. The pluri-annuality can be referred to the flowering inhibition of the lateral and basal branches, that takes place in a specimen and that keeps on for a long time, also after the full flowering of the principal axis. The basal shoots show a tendency to the vegetative growth, even though the external conditions are suitable to the flowering of the apical parts of the plant. Therefore we must attribute the pluriannuality of S. longistyla to this correlative flower-inhibiting mechanism. 相似文献
66.
67.
Nicola Bizzaro Elena Bartoloni Gabriella Morozzi Stefania Manganelli Valeria Riccieri Paola Sabatini Matteo Filippini Marilina Tampoia Antonella Afeltra Giandomenico Sebastiani Claudia Alpini Vittorio Bini Onelia Bistoni Alessia Alunno Roberto Gerli 《Arthritis research & therapy》2013,15(1):R16
Introduction
The diagnostic, predictive and prognostic role of anti-cyclic citrullinated peptide (CCP) antibodies in rheumatoid arthritis (RA) patients is widely accepted. Moreover, detection of these antibodies in subjects presenting with undifferentiated arthritis (UA) is associated with a significant risk to develop the disease. On the other hand, clinical and prognostic significance of evaluating anti-CCP levels in subjects with inflammatory arthritis at disease onset has not been fully clarified. The goal of this prospective study is to analyze the value and prognostic significance of anti-CCP titer quantification in UA subjects.Methods
Serial anti-CCP assays were measured in 192 consecutive patients presenting with UA lasting less than 12 weeks. Clinical and serological data and arthritis outcome were evaluated every 6 months until two years of follow-up.Results
Anti-CCP positivity, at both low and high titer, and arthritis of hand joints significantly predicted RA at two years, risk increasing in subjects with high anti-CCP titers at baseline. Moreover, time to RA diagnosis was shorter in patients with high anti-CCP2 titers at enrollment with respect to those with low antibody concentration.Conclusions
Presence of anti-CCP antibodies, at both low and high concentration, is significantly associated with RA development in subjects with recent onset UA. However, time interval from the onset of the first symptoms to the fulfilment of the classification criteria appears to be directly related to the initial anti-CCP level. 相似文献68.
Raffaele Saladino Paola Carlucci Claudia Crestini Pietro Tagliatesta Donato Monti Tristano Boschi 《Nucleosides, nucleotides & nucleic acids》2013,32(4-5):1123-1124
Abstract The oxidation of purine derivatives using porphyrins as catalysts and dimethyldioxirane (DMDO) as oxygen atom donor is reported. The regioselectivity of the oxidation was found to be dependent on the presence of a free OH moiety on the N(9)-side chain of the substrate and on the structure of the catalyst. 相似文献
69.
In this contribution the results of a zoogeographical analysis, carried out on the 123 endemic leaf beetle species (Coleoptera: Chrysomelidae) occurring in Italy and its immediately adjacent regions, are reported. To assess the level of faunistic similarity among the different geographic regions studied, a cluster analysis was performed, based on the endemic component. This was done by calculating the Baroni Urbani & Buser’s similarity index (BUB). Finally, a parsimony analysis of endemicity (PAE) was used to identify the most important areas of endemism in Italy. 相似文献