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231.
N Hammas L Chbani M Rami M Boubbou S Benmiloud Y Bouabdellah S Tizniti M Hida A Amarti 《Diagnostic pathology》2012,7(1):83
ABSTRACT: Inflammatory myofibroblastic tumor is a rare benign lesion whose tumor origin is now proven. It represents 0.7% of all lung tumors. We report the case of a three-year-old child who suffered from a chronic cough with recurrent respiratory infections. Chest X-ray and computed tomography revealed the presence of a left lower lobe lung mass. After pneumonectomy, histological examination combined with immunohistochemical study discovered an inflammatory myofibroblastic tumor. The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/8722069326962972. 相似文献
232.
We explore the utility of p-value weighting for enhancing the power to detect differential metabolites in a two-sample setting. Related gene expression information is used to assign an a priori importance level to each metabolite being tested. We map the gene expression to a metabolite through pathways and then gene expression information is summarized per-pathway using gene set enrichment tests. Through simulation we explore four styles of enrichment tests and four weight functions to convert the gene information into a meaningful p-value weight. We implement the p-value weighting on a prostate cancer metabolomic dataset. Gene expression on matched samples is used to construct the weights. Under certain regulatory conditions, the use of weighted p-values does not inflate the type I error above what we see for the un-weighted tests except in high correlation situations. The power to detect differential metabolites is notably increased in situations with disjoint pathways and shows moderate improvement, relative to the proportion of enriched pathways, when pathway membership overlaps. 相似文献
233.
Rivero M Furman N Mencacci N Picca P Toum L Lentz E Bravo-Almonacid F Mentaberry A 《Journal of biotechnology》2012,157(2):334-343
Solanum tuberosum plants were transformed with three genetic constructions expressing the Nicotiana tabacum AP24 osmotine, Phyllomedusa sauvagii dermaseptin and Gallus gallus lysozyme, and with a double-transgene construction expressing the AP24 and lysozyme sequences. Re-transformation of dermaseptin-transformed plants with the AP24/lysozyme construction allowed selection of plants simultaneously expressing the three transgenes. Potato lines expressing individual transgenes or double- and triple-transgene combinations were assayed for resistance to Erwinia carotovora using whole-plant and tuber infection assays. Resistance levels for both infection tests compared consistently for most potato lines and allowed selection of highly resistant phenotypes. Higher resistance levels were found in lines carrying the dermaseptin and lysozyme sequences, indicating that theses proteins are the major contributors to antibacterial activity. Similar results were obtained in tuber infection tests conducted with Streptomyces scabies. Plant lines showing the higher resistance to bacterial infections were challenged with Phytophthora infestans, Rhizoctonia solani and Fusarium solani. Considerable levels of resistance to each of these pathogens were evidenced employing semi-quantitative tests based in detached-leaf inoculation, fungal growth inhibition and in vitro plant inoculation. On the basis of these results, we propose that stacking of these transgenes is a promising approach to achieve resistance to both bacterial and fungal pathogens. 相似文献
234.
Jamali CA El Bouzidi L Bekkouche K Lahcen H Markouk M Wohlmuth H Leach D Abbad A 《Chemistry & biodiversity》2012,9(6):1188-1197
Samples of the aerial parts of Thymus broussonetii, T. ciliatus, T. leptobotrys, T. maroccanus, T. pallidus, T. satureioides, and T. serpyllum collected from different natural regions in southern and south-western Morocco were analyzed for their qualitative and quantitative essential oil profiles. In total, 46 compounds, representing more than 99% of the oils, were characterized. Monoterpenes, both hydrocarbons (12.9-58.0%) and oxygenated monoterpenes (38.8-81.1%), were the principal classes of compounds for most of the thyme species studied. Cluster analysis allowed the classification of the species into three main groups: a carvacrol group (Group I), comprising the species T. maroccanus and T. leptobotrys, a linalyl acetate and (E)-nerolidol group (Group II), represented by T. serpyllum, and a thymol and/or carvacrol, γ-terpinene, and p-cymene group (Group III), composed of T. satureioides, T. broussonetii, T. ciliatus, and T. pallidus. The essential oils were screened for their antioxidant and anticandidal activities. The data showed that the oils obtained from T. leptobotrys and T. maroccanus (carvacrol group) possessed the highest antioxidant activities as assessed by the determination of the DPPH free radical-scavenging ability and the ferric-reducing potential. The anticandidal assays indicated that the highest activity was noticed for the essential oil isolated from T. leptobotrys. 相似文献
235.
El Bouzidi L Abbad A Hassani L Fattarsi K Leach D Markouk M Legendre L Bekkouche K 《Chemistry & biodiversity》2012,9(3):598-605
The essential oils of leaves and flowers of the wild and cultivated Moroccan Achillea ageratum L., a rare and threatened medicinal species, were examined by GC/MS, and their chemical compositions were compared. At least nine components were identified in both wild and cultivated A. ageratum oils, representing more than 95% of the oils. Artemisyl acetate (62.34-78.79%), yomogi alcohol (4.89-12.40%), santolina alcohol (4.86-11.77%), and artemisia alcohol (3.36-7.04%) were the major compounds. Terpene-alcohol proportion was higher in wild A. ageratum than in cultivated A. ageratum. The antibacterial analysis showed that both oils presented high activity against all the studied Gram-positive strains in a range of MIC values from 2.55 to 7.02?mg/ml, but they appeared not effective against the tested Gram-negative ones (MIC values 20.40-41.10?mg/ml). They also exhibited remarkable antifungal activities against Candida species with MIC values ranging from 5.83 to 8.42?mg/ml. From these results, it was concluded that domestication of this threatened medicinal species using clonal propagation did not significantly affect its chemical composition and consequently its antimicrobial properties. 相似文献
236.
H Elghrib L Somoue N Elkhiati A Berraho A Makaoui N Bourhim S Salah O Ettahiri 《Comptes rendus biologies》2012,335(8):541-554
Marine phytoplankton was studied in January and July 2002 along of four transects: 32°30′N, 29°N, 24°30′N and 24°N. A total of 142 taxa were recorded in this area. The maximal specific richness, both in summer and in winter, was registered around Dakhla (24°N). The global spatiotemporal variability of species richness and specific diversity showed that the most structured and species-rich populations are situated in the coastal areas. The vertical variation of the two parameters showed homogeneity between depth levels. The maximal phytoplanktonic densities are recorded in the southern transects due to the permanent upwelling activity in the southern Atlantic coast. The bathymetric distribution of densities was more heterogeneous during summer, characterized by a high intensity of upwelling. The species Thalassionema nitzschioides, Asterionellopsis glacialis, Melosira, Chaetoceros and Leptocylindrus minimus are indicators of upwelling. 相似文献
237.
CA Martin U Siedlecka K Kemmerich J Lawrence J Cartledge L Guzadhur N Brice AA Grace C Schwiening CM Terracciano CL Huang 《Open biology》2012,2(6):120072
Brugada syndrome (BrS) is associated with ventricular tachycardia originating particularly in the right ventricle (RV). We explore electrophysiological features predisposing to such arrhythmic tendency and their possible RV localization in a heterozygotic Scn5a+/- murine model. Na(v)1.5 mRNA and protein expression were lower in Scn5a+/- than wild-type (WT), with a further reduction in the RV compared with the left ventricle (LV). RVs showed higher expression levels of K(v)4.2, K(v)4.3 and KChIP2 in both Scn5a+/- and WT. Action potential upstroke velocity and maximum Na(+) current (I(Na)) density were correspondingly decreased in Scn5a+/-, with a further reduction in the RV. The voltage dependence of inactivation was shifted to more negative values in Scn5a+/-. These findings are predictive of a localized depolarization abnormality leading to slowed conduction. Persistent Na(+) current (I(pNa)) density was decreased in a similar pattern to I(Na). RV transient outward current (I(to)) density was greater than LV in both WT and Scn5a+/-, and had larger time constants of inactivation. These findings were also consistent with the observation that AP durations were smallest in the RV of Scn5a+/-, fulfilling predictions of an increased heterogeneity of repolarization as an additional possible electrophysiological mechanism for arrhythmogenesis in BrS. 相似文献
238.
Ola Ugedal Tor F. Næsje Eva B. Thorstad Torbjørn Forseth Laila M. Saksgård Tor G. Heggberget 《Hydrobiologia》2008,609(1):9-23
The River Alta, northern Norway (70°N), was regulated for hydropower in 1987. Densities of juveniles and catches of adult
Atlantic salmon have been studied since 1980–1981 to examine the effects of regulation. The need to control environmental
variables during electrofishing was emphasized, as flow variables explained up to 42% of the variation in estimated juvenile
densities. The number of spawning redds was counted along the river from 1996 to 2005. The annual number of spawning redds
was correlated with the catch of multi-sea-winter salmon (predominantly females). In the upper 7 km section, just downstream
of the power station outlet, juvenile densities were reduced by 80% from pre-regulation levels to minimum levels in 1992–1996.
This was followed by partial recovery during 1997–2005, although not entirely back to pre-regulation levels. In contrast,
the general trend in the middle part of the river was a linear increase in juvenile densities during 1981–2005. Decreased
juvenile densities in the upper section was subsequently followed by reduced catches of adult salmon in this part of the river.
The relative catches of smolt year classes migrating to sea in the upper section was reduced by up to 75% from 1991 onwards.
Spawning and recruitment in the upper section have increased in recent years, probably back to the introduction of catch-and-release
angling and an increase in salmon runs. However, present day smolt production in the upper section is still reduced compared
to the middle part of the river, 18 years after regulation. The decreased densities of juvenile salmon in the upper section
were probably caused by several factors, of which stranding mortality due to sudden drops in the water level and increased
winter mortality due to changed environmental conditions, especially reduced ice-cover, may be the most important. In conclusion,
the regulation caused a considerable reduction of the salmon production in the upper 16% of salmon reaches, but did not affect
the salmon population negatively further downstream. This study illustrates that apparently small environmental disturbances
can cause large changes in Atlantic salmon abundance in high latitude populations.
Guest editors: R. L. Welcomme & G. Marmulla
Hydropower, Flood Control and Water Abstraction: Implications for Fish and Fisheries 相似文献
239.
Jack V. Tu Lorelei Nardi Jiming Fang Juan Liu Laila Khalid Helen Johansen for the Canadian Cardiovascular Outcomes Research Team 《CMAJ》2009,180(13):E118-E125
Background
Rates of death from cardiovascular and cerebrovascular diseases have been steadily declining over the past few decades. Whether such declines are occurring to a similar degree for common disorders such as acute myocardial infarction, heart failure and stroke is uncertain. We examined recent national trends in mortality and rates of hospital admission for these 3 conditions.Methods
We analyzed mortality data from Statistic Canada’s Canadian Mortality Database and data on hospital admissions from the Canadian Institute for Health Information’s Hospital Morbidity Database for the period 1994–2004. We determined age- and sex-standardized rates of death and hospital admissions per 100 000 population aged 20 years and over as well as in-hospital case-fatality rates.Results
The overall age- and sex-standardized rate of death from cardiovascular disease in Canada declined 30.0%, from 360.6 per 100 000 in 1994 to 252.5 per 100 000 in 2004. During the same period, the rate fell 38.1% for acute myocardial infarction, 23.5% for heart failure and 28.2% for stroke, with improvements observed across most age and sex groups. The age- and sex-standardized rate of hospital admissions decreased 27.6% for stroke and 27.2% for heart failure. The rate for acute myocardial infarction fell only 9.2%. In contrast, the relative decline in the inhospital case-fatality rate was greatest for acute myocardial infarction (33.1%; p < 0.001). Much smaller relative improvements in case-fatality rates were noted for heart failure (8.1%) and stroke (8.9%).Interpretation
The rates of death and hospital admissions for acute myocardial infarction, heart failure and stroke in Canada changed at different rates over the 10-year study period. Awareness of these trends may guide future efforts for health promotion and health care planning and help to determine priorities for research and treatment.Cardiovascular disease, including stroke, is the leading cause of death globally. Therefore, changes in the incidence and mortality of these disorders have a major impact on the overall health of a country’s population and on the health care system.1 Rates of death from cardiovascular and cerebrovascular disease have been steadily declining in Western Europe and North America for the past 3 decades.2,3 Whether this decline is occurring to a similar degree for common conditions such as acute myocardial infarction, heart failure and stroke is uncertain. Although these 3 conditions are associated with several common risk factors, the relative importance of risk factors such as smoking, hypertension and hyperlipidemia differs between them.4 Furthermore, the rate of new therapeutic advances for these conditions has varied in both the acute, in-hospital setting and in the outpatient setting, where primary and secondary prevention of events occurs.A comparative evaluation of recent population-based trends in incidence and mortality would provide an assessment of the relative progress achieved in preventing and treating these important conditions. Furthermore, the substantial economic impact of cardiovascular disease, including stroke, on the health care system — estimated at $18 billion per year in direct and indirect costs in Canada in 19985 — underscores the need for continued monitoring of cardiovascular disease and treatment outcomes. A study of temporal trends could also help guide future health promotion activities and health care planning.We conducted a study of recent trends in the rates of death and hospital admissions for acute myocardial infarction, heart failure and stroke in Canada from 1994 to 2004. We also studied whether changes in these trends occurred at similar rates in younger and older Canadians and in both sexes. 相似文献240.
With the development of new technologies for assaying biological activity on a global basis in experimental samples, various new "-omics" signatures have been developed to predict disease progression. Such signatures hold the potential to alter the nature of clinical management of human disease. In this article, we describe some necessary statistical considerations needed to take these signatures from the discovery phase to a clinically useful assay. Much of the work discussed is in the area of cancer. 相似文献