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561.
Alessandro Stella Nicoletta Resta Angela Polizzi Mariapina Montera Filomena Cariola Francesco Susca Viviana Gismondi Lucio Bertario Cristiana Marchese Romano Tenconi Maria Grazia Tibiletti Paola Izzo Mattia Gentile Fernando Prete Oronzo Pannarale Giovanni Di Matteo Paola Sala Liliana Varesco Cristina Mareni G. Guanti 《Human genetics》1998,102(6):624-628
In the present study, we used five different polymorphic markers to construct the haplotype at the adenomatous polyposis
coli (APC) locus in families with familial adenomatous polyposis (FAP) and in the normal Italian population. Non-ambiguous
haplotypes were reconstructed from 246 normal chromosomes and 65 FAP chromosomes. In the control population, the four polymorphisms
intragenic to APC gave rise to 16 haplotypes, the most common of which (II and XV) accounted for over 50% of all chromosomes.
In FAP patients, 13 haplotypes were found but their distribution was not statistically different from normal subjects. Eighty
complete chromosomal haplotypes (many fewer than the theoretical maximum of 208) for the five polymorphic sites assayed were
observed in the control population, 35 being found in the FAP patients. We compared the distribution of these haplotypes within
the two groups; no statistically significant differences between normal and FAP chromosomes were found. The elevated heterogeneity
of FAP chromosomes was clearly confirmed by the observation that 19 patients who carried one or other of the two most common
APC mutations (nt 3183 and nt 3927) showed 18 different haplotypes. On the basis of these results, we were not able to identify
a founder FAP chromosome. Various mechanisms are presented to explain this observation.
Received: 5 November 1997 / Accepted: 3 February 1998 相似文献
562.
563.
Intrauterine PGF2alpha (5mg) was administered for termination of early pregnancy in 14 healthy volunteers. With 11 complete abortions, the efficiency rate of this technique is below conventional methods. In addition, the incidience of infection was high occuring in 12 out of 14 subjects. Because of persistent bleeding, six patients underwent a dilatation and curettage. Other significant side effects included transient hypertension, pain, nausea and restlessness. In the patients with a complete abortion, the mean plasma progesterone concentration fell 37% after 8 hours post PGF2alpha instillation and 90iod and 75% over the next 14 days. 相似文献
564.
565.
In vitro antibacterial activities of ampicillin and amoxycillin were compared against pigmented and non-pigmented strains of Serratia marcescens. Ampicillin appeared more effective than amoxycillin; three-fourths of all strains consistently exhibited an ampicillin minimum inhibitory concentration (MIC) of at least one tube less than that recorded for amoxycillin. Complete cross resistance was not observed as has previously been inferred. Further, greater bactericidal activity was demonstrated with ampicillin; minimum bactericidal concentrations (MBC) were either the same as or one tube greater than the MIC. MBCs for amoxycillin, however, were significantly higher; often four to five times greater than the MIC. Ampicillin exhibited greater bactericidal activity as inferred from differences observed in the biological lesions induced, as recorded through observations by scanning electron microscopy (SEM). Spheroplasts were the predominant morphological alteration induced by ampicillin. In contrast, only filament formation, which demonstrated a degree of reversibility, was induced by amoxycillin. 相似文献
566.
F Mandelli A Cafolla L Annino S Amadori A Gentile P Bianco F Dianzani 《Journal of biological regulators and homeostatic agents》1987,1(4):177-182
Twenty-five patients with Hairy Cell Leukemia (HCL), eleven in post-splenectomy progressive disease, have been treated as out-patients with alpha 2 (r) Interferon (IFN) for twelve months. Eighteen patients completed the treatment: four achieved Complete Response (CR), twelve Partial Response (PR) and two Minor Response (MR). The response to IFN has been CR or PR in 89% of cases and MR in 11%. Even if the IFN effective dose and the length of treatment remain to be determined, IFN at relatively low dose seems to become the first treatment of choice in HCL patients. The remaining seven patients, still under treatment, already achieved PR at least. 相似文献
567.
- Intraspecific variation plays important roles in ecology and evolution. Yet, information on how species and populations vary remains scarce, particularly for insects and regarding functional traits. This lack of knowledge can be problematic in trait‐based ecology because traditional approaches assume negligible intraspecific variation, even for analyses that assess highly variable taxa.
- We measured 291 Arctic fritillary butterflies (Boloria chariclea) to assess the intraspecific variation in one population of this species, evaluating (i) how wingspan of Arctic fritillaries varies in relation to the other species of its community, and (ii) how well wingspan, a measure of body size, predicts weight, a measure of body mass.
- Wingspan of Arctic fritillaries varied between 2.62 and 4.07 cm, with the 95% interval range, including ~33% (14/42) of the species in the community, and ~30% (84/279) of the butterflies of Canada. The relationship between wingspan and weight was significant (βwingspan = 0.002, SE = 0.0008, P < 0.001), but relatively weak (R2adj = 0.31, F2,288 = 67.82, P < 0.001).
- We discuss our findings in relation to the assumption of species homogeneity and the use of proxies in the analysis of species traits, complementing our case study with simulations to illustrate how intraspecific and interspecific variation interact in determining when traditional trait analyses are robust. We suggest entomologists interested in trait analyses should critically evaluate how intraspecific variation could affect their inference, especially when evaluating species that are highly sexually dimorphic, phenotypically plastic, and/or distributed across broad environmental and spatial clines.
568.
A. Gentile M. Jàquez Gutiérrez J. Martinez A. Frattarelli P. Nota E. Caboni 《Plant Cell, Tissue and Organ Culture》2014,118(3):373-381
The effect of meta-Topolin (mT), an aromatic natural cytokinin, on micropropagation and adventitious shoot regeneration was evaluated on Prunus rootstocks, Torinel (Prunus domestica L.) and Ferdor (Prunus insititia × domestica). In vitro shoots were grown for three subcultures on a multiplication medium containing 2.1, 4.2 or 6.3 μM of mT or 2.1 µM N 6-benzyladenine (BA). Then, apical leaves were excised and transferred on a medium supplied with BA, thidiazuron (TDZ) or zeatin for adventitious regeneration. Shoots multiplied on 2.1 μM mT or BA, were also induced to root with α-naphthalene acetic acid and acclimatized. meta-Topolin did not improve shoot proliferation, respect to BA, however, positively influences growth and quality of shoots. Ferdor from mT showed higher rooting percentage (92 %), root number and length, respect to the control, while a similar response was observed in Torinel with both cytokinins. Acclimatisation was higher than 90 % for both genotypes and, after 5 months, the highest length of roots was found in plants from mT. Adventitious regeneration was obtained only in leaves from shoots previously grown on mT. The highest regeneration responses, 65 and 42 %, respectively for Ferdor and Torinel, were obtained in the regeneration medium supplied with TDZ. 相似文献
569.
L. Tesoriere D. Butera D. D'Arpa F. Di Gaudio M. Allegra C. Gentile 《Free radical research》2013,47(6):689-696
Betalains are natural pigments recently considered as compounds with potential antioxidative properties. In this work, ex vivo plasma spiking of pure either betanin or indicaxanthin, followed by isolation of low density lipoprotein (LDL), and measurement of its resistance to copper-induced oxidation, has been used to research if these betalains can bind to LDL and prevent oxidation of LDL lipids. When pooled human plasma from 10 healthy volunteers was incubated in the presence of 25–100?μM either betanin or indicaxanthin, incorporation of both compounds in LDL was observed, with a maximum binding of 0.52±0.08, and 0.51±0.06?nmoles of indicaxanthin and betanin, respectively, per mg LDL protein. Indicaxanthin-enriched and betanin-enriched LDL were more resistant than homologous native LDL to copper-induced oxidation, as assessed by the elongation of the induction period. The incorporated indicaxanthin, however, appeared twice as effective as betanin in increasing the length of the lag phase, while both compounds did not affect the propagation rate. Both betalains were consumed during the inhibition period of lipid oxidation, and delayed consumption of LDL-beta carotene. Indicaxanthin, but not betanin, prevented vitamin E consumption at the beginning of LDL oxidation, and prolonged the time of its utilization. The resistance of LDL to oxidation when vitamin E and indicaxanthin acted separately in a sequence, was lower than that measured when they were allowed to act in combination, indicating some synergistic interaction between the two molecules. No prooxidant effect over a large concentration range of either betanin or indicaxanthin was observed, when either betalain was added to the LDL system undergoing a copper-induced oxidation.These results show than indicaxanthin and betanin may bind to LDL, and are highly effective in preventing copper-induced lipid oxidation. Interaction with vitamin E appears to add a remarkable potential to indicaxanthin in the protection of LDL. Although molecular mechanisms remain uncompletely understood, various aspects of the action of betanin and indicaxanthin in preventing LDL lipid oxidation are discussed. 相似文献
570.
Classical power analysis for sample size determination is typically performed in clinical trials. A “hybrid” classical Bayesian or a “fully Bayesian” approach can be alternatively used in order to add flexibility to the design assumptions needed at the planning stage of the study and to explicitly incorporate prior information in the procedure. In this paper, we exploit and compare these approaches to obtain the optimal sample size of a single-arm trial based on Poisson data. We adopt exact methods to establish the rejection of the null hypothesis within a frequentist or a Bayesian perspective and suggest the use of a conservative criterion for sample size determination that accounts for the not strictly monotonic behavior of the power function in the presence of discrete data. A Shiny web app in R has been developed to provide a user-friendly interface to easily compute the optimal sample size according to the proposed criteria and to assure the reproducibility of the results. 相似文献