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Cytogenetic analyses conducted on several cases of melanoma have contributed to the identification of the chromosomal regions where the sequences responsible for malignant transformation and the evolution of this tumor are probably located. With regard to these problems, it is very important to have the possibility to analyze, through the use of cytogenetics, both the primary melanoma and the metastatic lesions from the same patient. We present a case in which the primary melanoma and five different metastases were studied by using cytogenetics. The primary tumor showed an inversion of chromosome 1 where the p36 region, often proposed in literature as the location of a melanoma susceptibility gene, was involved. Three cutaneous and one lymphonodal metastases presented the same nine clonal chromosomal aberrations. In particular, one is a further rearrangement of the marker present in the primary tumor; another is a deletion of the 9p21pter region in which the p16 gene is located. Our results can provide a contribution to the hypothesis of the location of a candidate gene for melanoma in the 1p36 region and can also underscore the role of the 9p21 region in the progression of melanoma.  相似文献   
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Nine microsatellite loci were isolated from the insect Dolichogenidea homoeosomae (Hymenoptera: Braconidae), an important parasitoid of the sunflower moth Homosoeosoma electellum (Lepidoptera: Pyralidae), and assayed for polymorphism. All nine loci were polymorphic within the five populations tested, with two to 14 alleles per locus. Expected and observed heterozygosities ranged from 0.39 to 0.90 and 0.25 to 0.72 respectively. These are the first microsatellite primers developed for D. homeosomae and will be useful for studies of population dynamics and connectivity.  相似文献   
3.
Mass spectrometry has been used to investigate the transportof CO2 in the freshwater diatom Navicula pelliculosa. The timecourseof CO2 formation in the dark after addition of 100 mmol m–3dissolved inorganic carbon (DIC) to cell suspensions showedthat no external carbonic anhydrase (CA) was present in thesecells. Upon illumination, cells pre-incubated at pH 75 with100 mmol m–3 DIC, removed almost all free CO2 from themedium at an initial rate of 285 µmol CO2 mg–1Chl h–1. Equilibrium between HCO3 and CO2 in themedium occurred rapidly upon addition of bovine CA, showingthat CO2 depletion resulted from a selective uptake of CO2 ratherthan an uptake of all inorganic carbon species. However, photosyntheticO2 evolution rate remained constant after CO2 had been depletedfrom the medium indicating that photosynthesis is sustainedprimarily by active HCO3 uptake. Treatment of cells with2-iodoacetamide (83 mol m–3) completely inhibited CO2fixation but had little effect on CO2 transport since initialrates of CO2 depletion were about 81% that of untreated cells.Transfer of iodoacetamide-treated cells to the dark caused arapid increase in the CO2 concentration in the medium largelydue to the efflux of the unfixed intracellular DIC pool whichwas found to be about 194 times the concentration of that inthe external medium. These results indicate that Navicula pelliculosaactively takes up molecular CO2 against a concentration gradientby a process distinct from HCO3 transport. Key words: Dissolved inorganic carbon, carbonic anhydrase, bicarbonate transport, CO2 transport, mass spectrometry  相似文献   
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  • 1 Bottlenose dolphins Tursiops truncatus are amongst the best‐known cetaceans. In the Mediterranean Sea, however, modern field studies of cetaceans did not start until the late 1980s. Bottlenose dolphins have been studied only in relatively small portions of the basin, and wide areas remain largely unexplored.
  • 2 This paper reviews the ecology, behaviour, interactions with fisheries and conservation status of Mediterranean bottlenose dolphins, and identifies threats likely to have affected them in historical and recent times.
  • 3 Whilst intentional killing was probably the most important cause of mortality until the 1960s, important ongoing threats include incidental mortality in fishing gear and the reduced availability of key prey caused by overfishing and environmental degradation throughout the region. Additional potential or likely threats include the toxic effects of xenobiotic chemicals, epizootic outbreaks, direct disturbance from boating and shipping, noise, and the consequences of climate change.
  • 4 The flexible social organization and opportunistic diet and behaviour of bottlenose dolphins may allow them to withstand at least some of the effects of overfishing and habitat degradation. However, dolphin abundance is thought to have declined considerably in the region and management measures are needed to prevent further decline.
  • 5 Management strategies that could benefit bottlenose dolphins, such as sustainable fishing, curbing marine pollution and protecting biodiversity, are already embedded in legislation and treaties. Compliance with those existing commitments and obligations should be given high priority.
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5.
Background: The rapid pace of progress in medical research, the consequent need for the timely transfer of new knowledge into practice, and the increasing need for ethics support, is making the work of Ethics Committees (ECs) ever more complex and demanding. As a response, ECs in many countries exhibit large variation in number, mandate, organization and member competences. This cross‐sectional study aims to give an overview of the different types of activities of Italian ECs and favour discussion at a European level. Methods: A questionnaire was emailed to all Italian Ethics Committees contained in the national Registry of the Ministry of Health, enquiring whether the EC was conducting, or planning to conduct, 4 specific activities. A telephone interview was conducted to determine reasons for failure to respond. Results: Response rate was 53% (101 respondents out of 191). 20% of ECs restrict their responsibilities to research protocol review, 25% also offer ethical consultation to institutions, support on individual health care decisions and promotes educational initiatives, while the remaining 50% conduct a few of the examined activities to varying degrees. Large variation was observed across different types of hosting institutions and geographical locations. Conclusions: A common European model should be developed, defining EC functions, member selection modalities, necessary member competences, decision‐making criteria and measures for work verification. In the absence of sound empirical evidence, it would be interesting to study the effectiveness and efficiency of the different existing models.  相似文献   
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