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831.
Ondrej Belan Consuelo Barroso Artur Kaczmarczyk Roopesh Anand Stefania Federico Nicola O’Reilly Matthew D. Newton Erik Maeots Radoslav I. Enchev Enrique Martinez-Perez David S. Rueda Simon J. Boulton 《Molecular cell》2021,81(5):1058-1073.e7
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832.
Mario Stefano Peragallo Florigio Lista Giuseppe Sarnicola Federico Marmo Alfredo Vecchione 《Cancer epidemiology》2010,34(1):47-54
Objective: An excess of cancer cases was reported in 2000 among Italian troops involved in peacekeeping operations in Bosnia and Kosovo. A preliminary assessment of cancer risk in this cohort was done for the period 1996–2007, based on cancer surveillance activity, which was started in 2001. Methods: A retrospective cohort study was done among 27 361 Italian Army soldiers deployed in Bosnia, 31 052 deployed in Kosovo, and a control group of non-deployed soldiers, whose number varies from 130 275 in 1996 to 40 967 in 2007. Standardized incidence ratio and 95% confidence intervals (SIR [95% CI]) of the main types of tumours were computed as the ratio of the observed and expected cases. Results: 98 incident cancers were reported among soldiers deployed in Bosnia, 66 in those stationed in Kosovo and 388 in non-deployed personnel. Overall, cancer incidence was lower than expected in all groups. Annual SIR was significantly higher than expected in 2000 for Hodgkin's lymphoma only among troops deployed in Bosnia (4.34 [1.18–11.12]) and non-deployed personnel (3.48 [1.67–6.39]); and in 2001 for thyroid cancer only among troops deployed in Bosnia (5.28 [1.44–13.51]). Conclusion: Although further investigation is needed, these preliminary results give no indication of an increased risk of cancer for Italian soldiers who were stationed in Bosnia and Kosovo. The cluster of Hodgkin's lymphoma in 2000 and of thyroid cancer in 2001 were sporadic events, they did not specifically affect deployed personnel and are unlikely to be related to environmental exposures in the Balkans. 相似文献
833.
Bivalve mitochondrial genomes show many uncommon features, like additional genes, high rates of gene rearrangement, high A-T content. Moreover, Doubly Uniparental Inheritance (DUI) is a distinctive inheritance mechanism allowing some bivalves to maintain and transmit two separate sex-linked mitochondrial genomes. Many bivalve mitochondrial features, such as gene extensions or additional ORFs, have been proposed to be related to DUI but, up to now, this topic is far from being understood. Several species are known to show this unusual organelle inheritance but, being widespread only among Unionidae and Mytilidae, DUI distribution is unclear. We sequenced and characterized the complete female- (F) and male-transmitted (M) mitochondrial genomes of Meretrix lamarckii, which, in fact, is the second species of the family Veneridae where DUI has been demonstrated so far. The two mitochondrial genomes are comparable in length and show roughly the same gene content and order, except for three additional tRNAs found in the M one. The two sex-linked genomes show an average nucleotide divergence of 16%. A 100-aminoacid insertion in M. lamarckii M-cox2 gene was found; moreover, additional ORFs have been found in both F and M Long Unassigned Regions of M. lamarckii. Even if no direct involvement in DUI process has been demonstrated so far, the finding of cox2 insertions and supernumerary ORFs in M. lamarckii both strengthens this hypothesis and widens the taxonomical distribution of such unusual features. Finally, the analysis of inter-sex genetic variability shows that DUI species form two separate clusters, namely Unionidae and Mytilidae+Veneridae; this dichotomy is probably due to different DUI regimes acting on separate taxa. 相似文献
834.
Claudia Ricci 《Hydrobiologia》1983,104(1):175-180
Nine species of Rotifera Bdelloidea have been cultured under laboratory conditions. The species were collected from two different environments: one group from water courses, the other from terrestrial mosses. Life tables have been determined and population dynamics parameters have been calculated. The characteristics of the life history seem to be related to the natural environmental conditions of the species. The patterns of reproductive output may develop as adaptations to different selective pressures: species from unpredictable environments face the probability of leaving no young at all, while species from stable environments are less conservative in their energy budget. Life characteristics are discussed from the point of view of adaptive strategies. 相似文献
835.
Enrica Marzola Nadia Desedime Cristina Giovannone Federico Amianto Secondo Fassino Giovanni Abbate-Daga 《PloS one》2015,10(4)
Anorexia nervosa (AN) is a life-threatening and difficult to treat mental illness with the highest mortality rates of any psychiatric disorder. We aimed to garner preliminary data on the real-world use of olanzapine and aripiprazole as augmentation agents of Selective Serotonin Reuptake Inhibitors (SSRIs) in adult inpatients affected by AN. We retrospectively evaluated the clinical charts of patients who were hospitalized between 2012 and 2014. Patients were evaluated upon admission and discharge. We investigated eating symptomatology, and both general and eating psychopathology using: Hamilton Rating Scale for Anxiety, Hamilton Rating Scale for Depression, and Yale-Brown-Cornell Eating Disorders Scale. The charts of 75 patients were included in this study. The sample resulted equally distributed among those receiving SSRIs and either aripiprazole or olanzapine in addition to SSRIs. Notwithstanding a few baseline clinical differences, upon discharge all groups were significantly improved on all measures. Interestingly, aripiprazole showed the greatest effectiveness in reducing eating-related preoccupations and rituals with a large effect size. The body of evidence on medication management in AN is in dismal condition. Augmentation therapy is a well-established approach to a variety of mental disorders and it is often used in every-day clinical practice with patients affected by AN as well. Nevertheless, to date very little data is available on this topic. Results from our sample yielded promising results on the effectiveness of aripiprazole augmentation in reducing eating-related obsessions and compulsions. Randomized controlled trials are warranted to confirm these encouraging findings. 相似文献
836.
A study of airborneAlternaria spores was carried out over the period from April 1992 to October 1993, in the Rehabilitation Medical Centre of Montescano
(PV), using an automatic volumetric spore trap (VPPS 2000 Lanzoni). The evaluation of the air concentration of these spores
is becoming ever more important as it is this mycophyte which is the commonest cause of a positive allergy test. In 1993 the
concentration ofAlternaria spores was much higher than in the previous year and the period of highest sporulation was different, depending on the different
rainfall pattern of the 2 years. 相似文献
837.
Leovigildo Quijano Federico Gómez G José S. Calderón Jesus López P Tirso Rios 《Phytochemistry》1984,23(1):125-127
Further investigation of Montanoa tomentosa afforded two new guaianolides as well as the known pumilin and the previously isolated heliangolide zoapatanolide A. The structures were established on the basis of spectroscopic studies and chemical evidence. 相似文献
838.
Dwarf males in monogonont rotifers 总被引:1,自引:0,他引:1
The main characteristics of the monogonont rotifer males are haploidy, dwarfism, progenesis and gut vestigialization to varying extents. Although these traits co-occur, they are probably unlinked from the evolutionary point of view. Commonly, all of these characteristics are directly related to the small size of the male egg, equipped with a reduced amount of yolk. A more ecological approach can, however, provide additional insights. Haploidy acts as a sex determining mechanism, dwarfism and progenesis derive directly from the egg size, while gut reduction is more evident in planktonic species than in benthic ones. This discrepancy suggests that the rotifers in the two habitats are exposed to different selection pressures. 相似文献
839.
L. Civalleri C. Pini A. Rigo R. Federico L. Calabrese G. Rotilio 《Molecular and cellular biochemistry》1982,47(1):3-9
Summary Three electrophoretic variants of superoxide dismutase can be detected in bovine erythrocytes by gel electrophoresis and electrofocusing. The two major forms, having isoelectric points at pH 5.2 and 4.9, were isolated by preparative focusing or chromatography. No differences were found in molecular weight, metal content, antigenicity, electron spin resonance spectrum, visible and ultraviolet optical spectra. In contrast, holo- and apo-superoxide dismutase, which have an electrophoretic mobility similar to that of the two major forms, showed unresolved isoelectric points but significantly different antigenicity. This result suggests that their different electrophoretic mobility is mainly conformation-related. The variant with pl 5.2, corresponding to the protein purified by ordinary procedures, was found to be inactivated by heat treatment faster than the other form. The latter one, on the other hand, gave rise to a multiple pattern of electrophoretic bands after incubation at 75 °C.It is suggested that superoxide dismutase multiplicity in erythrocytes is not genetically determined, but may be related to segregation of subunits, made non-identically by post translational asymmetrical modification. 相似文献
840.
Some structural and biochemical characteristics of polyamine oxidase (PAO) purified from maize shoots have been examined. The enzyme has only alanine as N-terminal amino acid and its N-terminal sequence shows a significant degree of homology with tryptophan 2-monooxygenase from Pseudomonas syringae pv. savastanoi. The pH optimum for the stability of the native enzyme is 5, similar to that of the barley leaf enzyme. Calorimetric analysis shows a single two-state transition at pH 6 with Tm 49.8 degrees. At pH 5 the thermal stability is increased by more than 14 degrees. Amine oxidation products, delta 1-pyrroline and diazabicyclononane, are competitive inhibitors of PAO activity (apparent Ki = 400 and 100 microM respectively). Moreover these compounds improve the thermal stability of the enzyme. N1-Acetylspermine, which is a good substrate for mammalian PAO, acts as a non-competitive inhibitor for the plant enzyme. 相似文献