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991.
Novel antitumoral agents with quinonic structure were synthesized and evaluated for their in vitro cytotoxic activities. This study examines the cytotoxic activities of several aryl benzo[g]isoquinoline-5,10-dione derivatives and a number of aminoacyl dihydrothieno[2,3-b]naphtho-4,9-dione (DTNQ) derivatives containing amino acids in position 3 of the ring system. Compound 6 showed remarkable cytotoxic activity at submicromolar concentration not only against several human leukaemia and solid tumour cell lines, but also toward sensitive and resistant human cell lines.  相似文献   
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993.
Insects use various types of behaviour, chemical defences, mimetic, aposematic or cryptic appearances as anti-predatory strategies. Among insects, carabid beetles of the genus Brachinus are distasteful prey because they discharge an irritating "cloud" of quinones when threatened. These beetles live in aggregations and adopt warning (conspicuous pattern) colours and chemicals to create a template that is easily learnt by predators. Another carabid beetle, Anchomenus dorsalis, mimics the colours and cuticular profile of Brachinus and is usually found in Brachinus aggregations. In this paper we report results from laboratory observations on feeding choice of the following natural predators - Crocidura leucodon (Insectivora: Soricidae), Ocypus olens (Coleoptera: Staphylinidae) and Podarcis sicula (Reptilia: Lacertidae) - on carabid beetle species. Comparing the number of attacks of predators towards aposematic and non-aposematic prey, there was a statistically significant preference towards non-aposematic prey.  相似文献   
994.
Carabidologists do it all’ (Niemelä 1996a) is a phrase with which most European carabidologists are familiar. Indeed, during the last half a century, professional and amateur entomologists have contributed enormously to our understanding of the basic biology of carabid beetles. The success of the field is in no small part due to regular European Carabidologists’ Meetings, which started in 1969 in Wijster, the Netherlands, with the 14th meeting again held in the Netherlands in 2009, celebrating the 40th anniversary of the first meeting and 50 years of long-term research in the Dwingelderveld. This paper offers a subjective summary of some of the major developments in carabidology since the 1960s. Taxonomy of the family Carabidae is now reasonably established, and the application of modern taxonomic tools has brought up several surprises like elsewhere in the animal kingdom. Progress has been made on the ultimate and proximate factors of seasonality and timing of reproduction, which only exceptionally show non-seasonality. Triggers can be linked to evolutionary events and plausibly explained by the “taxon cycle” theory. Fairly little is still known about certain feeding preferences, including granivory and ants, as well as unique life history strategies, such as ectoparasitism and predation on higher taxa. The study of carabids has been instrumental in developing metapopulation theory (even if it was termed differently). Dispersal is one of the areas intensively studied, and results show an intricate interaction between walking and flying as the major mechanisms. The ecological study of carabids is still hampered by some unresolved questions about sampling and data evaluation. It is recognised that knowledge is uneven, especially concerning larvae and species in tropical areas. By their abundance and wide distribution, carabid beetles can be useful in population studies, bioindication, conservation biology and landscape ecology. Indeed, 40 years of carabidological research have provided so much data and insights, that among insects - and arguably most other terrestrial organisms - carabid beetles are one of the most worthwhile model groups for biological studies.  相似文献   
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996.
Alström syndrome is a rare autosomal recessive genetic disorder characterized by cone-rod dystrophy, hearing loss, childhood truncal obesity, insulin resistance and hyperinsulinemia, type 2 diabetes, hypertriglyceridemia, short stature in adulthood, cardiomyopathy, and progressive pulmonary, hepatic, and renal dysfunction. Symptoms first appear in infancy and progressive development of multi-organ pathology leads to a reduced life expectancy. Variability in age of onset and severity of clinical symptoms, even within families, is likely due to genetic background.Alström syndrome is caused by mutations in ALMS1, a large gene comprised of 23 exons and coding for a protein of 4,169 amino acids. In general, ALMS1 gene defects include insertions, deletions, and nonsense mutations leading to protein truncations and found primarily in exons 8, 10 and 16. Multiple alternate splice forms exist. ALMS1 protein is found in centrosomes, basal bodies, and cytosol of all tissues affected by the disease. The identification of ALMS1 as a ciliary protein explains the range of observed phenotypes and their similarity to those of other ciliopathies such as Bardet-Biedl syndrome.Studies involving murine and cellular models of Alström syndrome have provided insight into the pathogenic mechanisms underlying obesity and type 2 diabetes, and other clinical problems. Ultimately, research into the pathogenesis of Alström syndrome should lead to better management and treatments for individuals, and have potentially important ramifications for other rare ciliopathies, as well as more common causes of obesity and diabetes, and other conditions common in the general population.  相似文献   
997.
Projections of climate-change scenarios indicate that many Maculinea arion populations will disappear from Europe over the next 50 years. Extinctions will be particularly concentrated around the southern limits of the species?? range, such as the Italian peninsula, except mountain populations, mainly in the Alps. M. arion is a social parasite of Myrmica ants and its survival depends on the presence and abundance of two resources, i.e. (1) a specific larval foodplant and (2) a suitable Myrmica host ant. We collected data on Thymus plants distribution, Myrmica ants abundance, turf height around Myrmica nests, distance between nests and the closest thyme plant (Thymus pulegioides), and vegetation structure at 14 patches of a M. arion fragmented population occurring in the Western Italian Alps (Val Ferret: Aosta). We found that patches with the highest abundance of M. arion had significantly higher foodplant abundance. Among 407 nests belonging to nine Myrmica species, we found M. arion larvae in one Myrmica lonae and in two Myrmica sulcinodis nests. The distribution of M. sulcinodis nests showed the best spatial overlap with Thymus plants. M. sulcinodis was also significantly more abundant on pastures showing high M. arion density, and therefore offered higher adoption probabilities to develop butterfly larvae. On M. arion habitat patches, the mean turf height around Myrmica nests varied from 10.5 to 22.3 cm and best matched the habitat requirements of T. pulegioides. Thus, we suggest that extensive grazing is needed to maintain the two most important resources for M. arion. Moreover, patches where M. arion was abundant included more numerous plant species characteristic of these mountain pastures, as well as higher plant diversity (Shannon index). As a consequence, M. arion represents an umbrella species and a good indicator for the conservation status of mountain grasslands.  相似文献   
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BackgroundThe authors presented their experience in regenerative surgery of post-traumatic lower extremity ulcers, evaluating the effects related to the use of Enhanced Stromal Vascular Fraction (e-SVF) and Fat Grafting with Platelet rich Plasma (PRP). The authors compared the results of two control groups.MethodThe analysis involved 20 patients aged between 23 to 62 years affected by post-traumatic lower extremity ulcers. 10 patients managed with e-SVF and 10 patients managed with Fat grafting + PRP in the Plastic and Reconstructive Surgery Department at “Tor Vergata” University Rome. Patients in the first control group (n = 10), were treated only with curettage and application of hyaluronic acid in the bed of ulcers. Patients in the second control group (n = 10), were treated only with PRP.ResultsThe authors showed that wounds treated with e-SVF healed better than those treated with hyaluronic acid. In fact, after 9.7 weeks, patients treated with e-SVF underwent 97.9% ± 1.5% reepithelialisation compared to 87.8% ± 4.4% of the first control group (only hyaluronic acid; p < 0.05). Patients treated with PRP and fat grafting also showed an improvement in reepithelialisation; in fact after 9.7 weeks, they underwent a 97.8% ± 1.5% reepithelialisation compared to 89.1% ± 3.8% of the second control group (only PRP; p < 0.05). As reported e-SVF and PRP mixed with fat grafting were the two treatments evidencing improvement in the healing of patients post-traumatic extremity ulcers.ConclusionsThe results obtained proved the efficacy of these treatments, and the satisfaction of the patients confirmed the quality of the results.  相似文献   
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