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11.
Genomic rearrangements resulting in activating kinase fusions have been increasingly described in a number of cancers including malignant melanoma, but their frequency in specific melanoma subtypes has not been reported. We used break‐apart fluorescence in situ hybridization (FISH) to identify genomic rearrangements in tissues from 59 patients with various types of malignant melanoma including acral lentiginous, mucosal, superficial spreading, and nodular. We identified four genomic rearrangements involving the genes BRAF, RET, and ROS1. Of these, three were confirmed by Immunohistochemistry (IHC) or sequencing and one was found to be an ARMC10‐BRAF fusion that has not been previously reported in melanoma. These fusions occurred in different subtypes of melanoma but all in tumors lacking known driver mutations. Our data suggest gene fusions are more common than previously thought and should be further explored particularly in melanomas lacking known driver mutations.  相似文献   
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13.
Although the faunal elements of Far East Asian Mesozoic terrestrial biota have attracted much attention in recent years, their palaeoecology remains poorly known. In particular, features of the palaeoclimate are highly controversial. To address this point we used the Mesozoic fossil wood Xenoxylon , a genus recognized as an indicator of wet temperate biotopes and which is common in the area during the Carnian–Maastrichtian interval. We re-appraised bibliographic data and gathered new data for Xenoxylon in the Mesozoic of Far East Asia. This demonstrated that previous taxonomic approaches to the genus have been so far idiosyncratic. We examined the anatomical diversity of morphogenus Xenoxylon in Far East Asia and compared it to that of samples from Europe. This indicates that in an area centred on north-eastern China, Xenoxylon reached a level of anatomical diversity unmatched elsewhere in the world. We hypothesize that this diversity witnesses the persistence of palaeoecological conditions particularly suitable for Xenoxylon and that a wet temperate climate prevailed over most of the area throughout the Carnian–Maastrichtian interval. It is in this setting that the famous Jehol Biota probably evolved.  相似文献   
14.
Strain RB1401 contains a plasmid with a fusion between the upper pathway promoter of the TOL plasmid xyl genes and a lux gene cassette. Bioluminescence activity appeared in the early period of biodegradation of m-xylene, and was observed at all tested conditions of temperature (15, 27, 35°C) and pH (5, 7, 9), showing in the range of 300 ~ 6100 RLU. Biokinetics of strain RB1401 in the presence of m-xylene were as follows: Y 0.56 mg/mg, μmax 2.67 day-1, and Ks 19.25 mg/L. A ratio of C:N(KNO3):P(KH2PO4) = 100:8:1.5 and 0.01% (w/v) of H2O2 were chosen for optimum biostimulation conditions of RB1401 with m-xylene in soil system. These results demonstrate the capability of such a genetically engineered bacteria for the development of biomonitoring and bioremediation in soil environments contaminated with specific volatile organic compounds.  相似文献   
15.
BackgroundMalaria remains endemic at low levels in the south-eastern provinces of Iran bordering Afghanistan and Pakistan, with the majority of cases attributable to P. vivax. The national guidelines recommend chloroquine (CQ) as blood-stage treatment for uncomplicated P. vivax, but the large influx of imported cases enhances the risk of introducing CQ resistance (CQR).ConclusionsThe contrasting low versus high diversity in the two sub-populations (K1 and K2) infers that a combination of local transmission and cross-border malaria from higher transmission regions shape the genetic make-up of the P. vivax population in south-eastern Iran. There was no molecular evidence of CQR amongst the local or imported cases, but ongoing clinical surveillance is warranted.  相似文献   
16.
The ecophysiological response of an alpine grassland to recent climate change and increasing atmospheric CO2 concentration was investigated with a new strategy to go back in time: using a time‐series of Capra ibex horns as archives of the alpine grasslands' carbon isotope discrimination (13Δ). From the collection of the Natural History Museum of Bern, horns of 24 males from the population of the Augstmatthorn–Brienzer Rothorn mountains, Switzerland, were sampled covering the period from 1938 to 2006. Samples were taken from the beginning of each year‐ring of the horns, representing the beginning of the horn growth period, the spring. The horns' carbon 13C content (Δ13C) declined together with that of atmospheric CO2 over the 69‐year period, but 13Δ increased slightly (+0.4‰), though significantly (P<0.05), over the observation period. Estimated intercellular CO2 concentration increased (+56 μmol mol?1) less than the atmospheric CO2 concentration (+81 μmol mol?1), so that intrinsic water‐use efficiency increased by 17.8% during the 69‐year period. However, the atmospheric evaporative demand at the site increased by approximately 0.1 kPa between 1955 and 2006, thus counteracting the improvement of intrinsic water‐use efficiency. As a result, instantaneous water‐use efficiency did not change. The observed changes in intrinsic water‐use efficiency were in the same range as those of trees (as reported by others), indicating that leaf‐level control of water‐use efficiency of grassland and forests followed the same principles. This is the first reconstruction of the water‐use efficiency response of a natural grassland ecosystem to last century CO2 and climatic changes. The results indicate that the alpine grassland community has responded to climate change by improving the physiological control of carbon gain to water loss, following the increases in atmospheric CO2 and evaporative demand. But, effective leaf‐level water‐use efficiency has remained unchanged.  相似文献   
17.
Autoimmunity to the central nervous system (CNS), especially to myelin basic protein (MBP), may play a causal role in autism, a neurodevelopmental disorder. Because many autistic children harbor elevated levels of measles antibodies, we conducted a serological study of measles-mumps-rubella (MMR) and MBP autoantibodies. Using serum samples of 125 autistic children and 92 control children, antibodies were assayed by ELISA or immunoblotting methods. ELISA analysis showed a significant increase in the level of MMR antibodies in autistic children. Immunoblotting analysis revealed the presence of an unusual MMR antibody in 75 of 125 (60%) autistic sera but not in control sera. This antibody specifically detected a protein of 73-75 kD of MMR. This protein band, as analyzed with monoclonal antibodies, was immunopositive for measles hemagglutinin (HA) protein but not for measles nucleoprotein and rubella or mumps viral proteins. Thus the MMR antibody in autistic sera detected measles HA protein, which is unique to the measles subunit of the vaccine. Furthermore, over 90% of MMR antibody-positive autistic sera were also positive for MBP autoantibodies, suggesting a strong association between MMR and CNS autoimmunity in autism. Stemming from this evidence, we suggest that an inappropriate antibody response to MMR, specifically the measles component thereof, might be related to pathogenesis of autism.  相似文献   
18.
DNA sequence variation in a 1.1-kb region including the coding portion of the Tpi locus was examined in 25 homozygous third-chromosome lines of Drosophila melanogaster, nine lines of Drosophila simulans, and one line of Drosophila yakuba. Our data show that the widespread allozyme polymorphism observed in cosmopolitan D. melanogaster is due to a glutamic acid substitution occurring in a phylogenetically conserved lysine that has been identified as part of the "hinged-lid" active site of the enzyme. This observation suggests that the replacement polymorphism may have important functional consequences. One replacement polymorphism was also observed in D. simulans, although its functional relevance is more difficult to assess, since it affects a site that is not strongly conserved. This amino acid change in D. simulans is associated with a single lineage possessing seven unique silent substitutions, which may be indicative of balancing selection or population subdivision. The absence of fixed amino acid differences between D. melanogaster and D. simulans and only a single difference with D. yakuba suggests that triose phosphate isomerase is under strong functional constraint. Silent variation is slightly higher for D. melanogaster than for D. simulans. Finally, we outline the general lack of evidence for old balanced polymorphisms at allozyme loci in D. melanogaster.   相似文献   
19.
1植物名称异株藤(Calamus dioicus)。 2材料类别胚。 3培养条件(1)胚芽生长培养基:MS+6-BA 2.0 mg·L一(单位下同)+4%蔗糖;(2)丛芽诱导培养基:MS+6-BA 4.0+IBA 1.0+NAA 1.0+4%蔗糖;(3)生根培养基1/2MS(大量元素减半)+IBA 0.5+NAA 0.5+3%蔗糖。培养基(1)和(2)加0.7%卡拉胶,培养基(3)加0.73%卡拉胶,pH 5.8±0.2。培养温度(28±2)℃,每天光照10 h,光照度为2 000 k。 4生长与分化情况 4.1 萌发果实大量成熟前一个半月采集近成熟果实,去除果肉得干净种子,用75%酒精浸泡30 s,0.1%升汞表面消毒加~30 min,无菌水冲洗4~5次,在超净台上用刀片将发芽孔打开后转接至培养基(1)。种子在培养基(1)上30 d,与田间播种相同,胚根先长出发芽孔,但受6-BA的作用,胚根长至0.5~1.0 cm即不再进一步生长。接种∞d,胚芽长出发芽孔,∞d长至1.5~2.0 cm高,即可切下胚芽转入丛芽诱导培养基(2)。 4.2 丛芽诱导在培养基(2)中,胚芽高生长明显减缓,基部开始横向膨胀生长,约40d分化出丛芽,丛芽诱导率为30%~35%。  相似文献   
20.
ABSTRACT. Symbiont-bearing xD amoebae no longer produce a 45-kDa cytoplasmic protein that functions as S-adenosylmethionine synthetase in symbiont-free D amoebae. The absence of the protein in xD amoebae is attributable to xD amoeba's failure to transcribe the corresponding gene as a result of harboring bacterial symbionts. However, xD amoebae have about half the level of enzyme activity found in D amoebae, indicating that they use an alternative source for the enzyme. xD amoebae originated from D amoebae by bacterial infection and now depend on their symbionts for survival. xD amoebae exhibit irreversible nucleolar abnormalities when their symbionts are removed, suggesting that X-bacteria supply the needed enzyme. A monoclonal antibody against the 45-kDa protein was produced and used as a probe in cloning its corresponding cDNA. The product of the cDNA was found to have S-adenosylmethionine synthetase activity. These results show how symbiotic X-bacteria may become essential cellular components of amoebae by supplementing a genetic defect for an amoeba's house-keeping gene that is brought about by an action of X-bacteria themselves. This is the first reported example in which symbionts alter the host's gene expression to block the production of an essential protein.  相似文献   
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