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Only 20-25% of families screened for BRCA1/2 mutations are found positive. Because only a positive result is informative, we studied the role of BRCA1/2 immunohistochemistry as an additional method for patient selection. From 53 high-risk-affected probands, 18 (34%) had available paraffin blocks of their tumors and were selected for this study. Mutation screening was done by conformation-sensitive gel electrophoresis and multiplex ligation-dependent probe amplification. For immunohistochemistry, 21 neoplastic specimens (15 breast carcinomas, 5 ovary neoplasms, and 1 rectal adenocarcinoma) were analyzed with BRCA1 (monoclonal antibody, Ab-1, oncogene) and BRCA2 (polyclonal antibody, Ab-2, oncogene) antibodies. Absence of the BRCA1 protein was confirmed in negative tumors by Western blotting. Seven patients were positive for BRCA1/2 mutations: 5 for BRCA1 and 2 for BRCA2. Four out of five positive patients had tumors negative for BRCA1 immunostaining, and the remaining 13 BRCA1-negative patients had positive BRCA1 immunostaining in all tumor samples. Sensitivity to predict for BRCA1 mutation carriers was 80%, and specificity was 100%, with a positive predictive value of 100% and a negative predictive value of 93%. This correlation was statistically significant (p=0.001). No correlation was observed for BRCA2. If larger studies confirm these results, high-risk patients with BRCA1-negative tumors should be screened first for this gene.  相似文献   
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The phylogenetic relationships among the wall lizards of the Podarcis hispanicus complex that inhabit the south-east (SE) of the Iberian Peninsula and other lineages of the complex remain unclear. In this study, four mitochondrial and two nuclear markers were used to study genetic relationships within this complex. The phylogenetic analyses based on mtDNA gene trees constructed with ML and BI, and a species tree using *BEAST support three divergent clades in this region: the Valencia, Galera and Albacete/Murcia lineages. These three lineages were also corroborated in species delimitation analyses based on mtDNA using bPTP, mPTP, GMYC, ABGD and BAPS. Bayesian inference species delimitation method (BPP) based on both nuclear data and a combined data set (mtDNA + nuclear) showed high posterior probabilities for these three SE lineages (≥0.94) and another Bayesian analysis (STACEY) based on combined data set recovered the same three groups in this region. Divergence time dating of the species tree provided an estimated divergence of the Galera lineage from the other SE group (Podarcis vaucheri, (Albacete/Murcia, Valencia)) at 12.48 Ma. During this period, the Betic–Rifian arc was isolated, which could have caused the isolation of the Galera form distributed to the south of the Betic Corridor. Although lizards from the Albacete/Murcia and Galera lineage are morphologically similar, they clearly represent distinct genetic lineages. The noteworthy separation of the Galera lineage enables us to conclude that this lineage must be considered as a new full species.  相似文献   
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Corynebacterium equi IFO 3730 was found to oxidize a wide variety of sec-alcohols, including alkanols, substituted alkanols, alkenols and cyclic alcohols, in moderate to high yields. Among them, the sec-alcohols which have longer carbon chains were oxidized more smoothly than those with smaller numbers of carbon. Although both enantiomers of unsymmetrically disubstituted carbinols were oxidized, the S form of 2-dodecanol was converted to the corresponding ketone a little faster than the other enantiomer.  相似文献   
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Social behaviour ofRopalidia revolutionalis (de Saussure) was observed in Brisbane and Townsville. Nests were, as a rule, founded by association of females. Each nest began as a single comb but, after the emergence of progeny adults, satellite combs were constructed near the original comb. During the pre-emergence (single-comb) stage, each colony had a single egg-layer, despite the rare occurrence of intranidal dominance acts among female wasps. When colonies had reached the multiple-comb stage, the frequency and intensity of intranidal dominance-aggressive acts rose to a high level, comparable to those of typically aggressive colonies of e.g.Polistes canadensis in Panama. Colonies appeared to be still functionally haplometrotic during the early phase of multiple-comb stage, but several potential egg-layers were present as colony size increased. Dominant females often performed wing vibration, rapid runs between combs and tended to sit on the largest comb, whilst subordinate females tended to sit on smaller combs.  相似文献   
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It is shown that in bulbous Iris zeatin originates from a nucleotide. This nucleotide is probably zeatin-allylic-phosphate, in which a phosphate group is attached to the isoprenoid side-chain of zeatin. The formation of zeatin-allylic-phosphate from t-zeatin and 8-[14C]-zeatin by the microsomal fractions of Iris bulb disks and Helianthus tubers was demonstrated. The responsible enzyme was partially purified. 5-AMP was found to be a phosphate group delivering substrate. Adenosine and adenine inhibited the enzyme reaction. The significance of the results is discussed in relation to cytokinin biosynthesis and the occurrence of bud blast in Iris.  相似文献   
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Laboratory studies with the southern green stink bug, Nezara viridula (L.) (Hemiptera: Pentatomidae), feeding on seeds or fruits of some alternate host plants, demonstrated differences in nymphal survival and development time, and body weight at adult emergence. Lowest mortalities (25%) were observed for nymphs on fruits of dakota mustard [Brassica kaber (DC.)] and siberian motherwort (Leonurus sibiricus L.). On fruits of castor bean (Ricinus communis L.) nymph mortality was ca. 60%, and on mature seeds of L. sibiricus ca. 75%. Total development time from second instar to adult ranged from ca. 26 days on B. kaber to ca. 42 days on R. communis. Fresh body weight at adult emergence was greatest for nymphs on L. sibiricus and lowest on R. communis. Adult survival after 30 days and mean longevity was greater on L. sibiricus than on the remaining foods, being drastically reduced on R. communis. In general, reproductive performance on all foods was similar, except R. communis, on which no female reproduced. Female weight gain of N. viridula was generally greater on L. sibiricus On R. communis, adults lost weight during their first week and showed the lowest weight gain at the end of day 29. Field observations coupled with these laboratory studies suggest that in the Warta area (northern Paraná state, Brazil, 23° 11 S), L. sibiricus and B. kaber are important alternate food plants in the seasonal phenology of N. viridula. R. communis, however, is of poor nutritional quality, serving primarily as a refuge.
Résumé L'alimentation au laboratoire de N. viridula avec les graines et les fruits de diverses plantes a entraîné différentes mortalités larvaires, différentes vitesses de développement et des différences dans les poids des adultes à l'émergence. Les mortalités les plus faibles (25%) on été observées avec les fruits de Brassica kaber DC. et de Leonurus sibiricus L.Avec les fruits de Ricinus communis L., la mortalité larvaire était de 60%; sur graines mûres de L. sibiricus, elle était de 75%. La durée du développement du second stade à l'adulte a varié de 26 jours sur B. kaber à 42 jours sur R. communis. Le poids frais des adultes à l'émergence était le plus élevé avec L. sibiricus et le plus faible avec de R. communis. La longévité des adultes au-delà de 30 jours était la plus élevée avec L. sibiricus, et était fortement réduite avec R. communis. Dans l'ensemble, la reproduction était de même importance avec les différents aliments, à l'exception de R. communis avec lequel les femelles ne se reproduisaient pas. Le gain de poids des femelles était généralement supérieur avec L. sibiricus; avec R. communis les adultes ont perdu du poids pendant la première semaine et ont présenté le plus faible gain à la fin du 29ème jour.Des observations dans la nature, associées à ces expériences de laboratoire, laissent supposer que dans la zone de Warta (au Nord de l'état de Paraná, 23° 11 S, au Bresil), L. sibiricus et B. kaber sont des plantes hôtes alternatives importantes dans la phénologie saisonnière de N. viridula. Cependant, R. communis, de faible valeur alimentaire, sert avant tout de refuge.
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