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Germline mutations in the BRCA1 and BRCA2 genes contribute to approximately 18% of hereditary ovarian cancers conferring an estimated lifetime risk from 15% to 50%. A variable incidence of mutations has been reported for these genes in ovarian cancer cases from different populations. In Greece, six mutations in BRCA1 account for 63% of all mutations detected in both BRCA1 and BRCA2 genes. This study aimed to determine the prevalence of BRCA1 mutations in a Greek cohort of 106 familial ovarian cancer patients that had strong family history or metachronous breast cancer and 592 sporadic ovarian cancer cases. All 698 patients were screened for the six recurrent Greek mutations (including founder mutations c.5266dupC, p.G1738R and the three large deletions of exon 20, exons 23–24 and exon 24). In familial cases, the BRCA1 gene was consequently screened for exons 5, 11, 12, 20, 21, 22, 23, 24. A deleterious BRCA1 mutation was found in 43/106 (40.6%) of familial cancer cases and in 27/592 (4.6%) of sporadic cases. The variant of unknown clinical significance p.V1833M was identified in 9/698 patients (1.3%). The majority of BRCA1 carriers (71.2%) presented a high-grade serous phenotype. Identifying a mutation in the BRCA1 gene among breast and/or ovarian cancer families is important, as it enables carriers to take preventive measures. All ovarian cancer patients with a serous phenotype should be considered for genetic testing. Further studies are warranted to determine the prevalence of mutations in the rest of the BRCA1 gene, in the BRCA2 gene, and other novel predisposing genes for breast and ovarian cancer.  相似文献   
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Laboratory experiments were carried out to evaluated three diatomaceous earth (DE) formulations--Protect-It, PyriSec (at dose rates 500, 1000, and 1500 ppm), and DEA-P (at dose rates 75, 150, and 500 ppm)--against the larger grain borer, Prostephanus truncatus (Horn) (Coleoptera: Bostrychidae), adults in stored maize, Zea mays L., at three temperatures (20, 25, and 30 degrees C) and two relative humidity (RH) levels (55 and 75%). At these conditions, the capability of progeny production in the treated substrate also was assessed. Adult survival was high, at all doses of Protect-It and PyriSec. Progeny production was also high. In contrast with the other two DEs, DEA-P was highly effective and caused complete mortality to the exposed P. truncatus adults, even at the lowest dose rate (75 ppm). In addition, progeny production was completely suppressed. Generally, Protect-it and PyriSec were more effective at 20 degrees C than at 30 degrees C. In contrast, the efficacy of DEA-P was continuously high in all temperatures and relative humidities examined.  相似文献   
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Oncogenic BRAF mutations are more frequent in cutaneous melanoma occurring at sites with little or moderate sun-induced damage than at sites with severe cumulative solar ultraviolet (UV) damage. We studied cutaneous melanomas from geographic regions with different levels of ambient UV radiation to delineate the relative effects of cumulative UV damage, age, and anatomic site on the frequency of BRAF mutations. We show that BRAF-mutated melanomas occur in a younger age group on skin without marked solar elastosis and less frequently affect the head and neck area, compared to melanomas without BRAF mutations. The findings indicate that BRAF-mutated melanomas arise early in life at low cumulative UV doses, whereas melanomas without BRAF mutations require accumulation of high UV doses over time. The effect of anatomic site on the mutation spectrum further suggests regional differences among cutaneous melanocytes.  相似文献   
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Hydrolysis of cellulosic wastes has been applied for environmental purposes and glucose production. An enzymatic process is proposed for such treatment of municipal cellulosic wastes, and the optimum conditions are described. It was found that different conditions should be applied for the treatment of soft or hard paper wastes, the most characteristic being pretreatment of wastes and temperature of the treatment process. Optimization of enzyme characteristics was also examined after stabilization of the enzymes by cross-linking. Endocellulase was better stabilized after cross-linking with EDAC whereas, exocellulase was better with glutaraldehyde. The application of cross-linked enzyme in the waste paper treatment process resulted in about a 25% increase of glucose liberation.  相似文献   
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The insecticidal effect of spinosad dust, a formulation that contains 0.125% spinosad, was evaluated against adults of Sitophilus oryzae (L.) and Rhyzopertha dominica (F.) at three temperature levels (20, 25, and 30 degrees C) and four commodities (wheat, Triticum aestivum L.; barley, Hordeum vulgare L.; rice, Oryza sativa L.; and maize, Zea mays L.). For this purpose, quantities of the above-mentioned grains were treated with spinosad at two dose rates (20 and 50 ppm of the formulation, corresponding to 0.025 and 0.06 ppm AI, respectively), and mortality of the exposed adults in the treated grains was measured after 7 and 14 d, whereas progeny production was assessed 65 d later. Generally, for both species, mortality increased with dose, exposure interval, and temperature. For S. oryzae, adult survival and progeny production were lower on wheat than the other grains. After 14 d of exposure, mortality of S. oryzae adults on wheat treated with 50 ppm ranged between 61 and 98%, whereas in the other three commodities it did not exceed 42%. Mortality of R. dominica after 14 d on grains treated 50 ppm ranged between 91 and 100%. For this species, progeny production from exposed parental adults was low in all commodities regardless of temperature. Results indicate that spinosad dust can be used as an alternative to traditional grain protectants, but its effectiveness is highly determined by the target species, commodity, dose, and temperature.  相似文献   
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HeLa cells synthesize heterogeneous nuclear RNA (HnRNA) in the G1, S, and G2 portions of the cell cycle. HnRNA prepared from these various periods was compared by RNA-DNA hybridization experiments. The results indicated that some of the HnRNA molecules were equivalent at all times in the cell cycle, but limitations in the sensitivity of the hydridization reactions, as well as in the spectrum of hybridizing molecules, restrict the conclusions that can be drawn from these comparisons.  相似文献   
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