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The complex repeats of Dictyostelium discoideum   总被引:2,自引:0,他引:2       下载免费PDF全文
In the course of determining the sequence of the Dictyostelium discoideum genome we have characterized in detail the quantity and nature of interspersed repetitive elements present in this species. Several of the most abundant small complex repeats and transposons (DIRS-1; TRE3-A,B; TRE5-A; skipper; Tdd-4; H3R) have been described previously. In our analysis we have identified additional elements. Thus, we can now present a complete list of complex repetitive elements in D. discoideum. All elements add up to 10% of the genome. Some of the newly described elements belong to established classes (TRE3-C, D; TRE5-B,C; DGLT-A,P; Tdd-5). However, we have also defined two new classes of DNA transposable elements (DDT and thug) that have not been described thus far. Based on the nucleotide amount, we calculated the least copy number in each family. These vary between <10 up to >200 copies. Unique sequences adjacent to the element ends and truncation points in elements gave a measure for the fragmentation of the elements. Furthermore, we describe the diversity of single elements with regard to polymorphisms and conserved structures. All elements show insertion preference into loci in which other elements of the same family reside. The analysis of the complex repeats is a valuable data resource for the ongoing assembly of whole D. discoideum chromosomes.  相似文献   
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A massive hemispheric high-grade astrocytoma, diagnosed in a 6-week-old infant, was totally excised by means of two craniotomies. The child is still alive and well with minimal neurological dysfunction 1.5 years after operation. This case report illustrates the benefit of aggressive surgical excision (without radiation or chemotherapy) of massive malignant neonatal astrocytomas. While surgical deficits may be minimized by the plasticity of the developing nervous system, extensive excision may yield occasional long-term palliation.  相似文献   
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The purpose of this study was to characterize triathletes and to assess their responses to prolonged, strenuous competition. Nine triathletes (6 males, 3 females) participated. Mean V0(2)max and percentage of body fat were 72.0 ml X kg-1 X min-1 and 7.1%, respectively, in the four males who finished in the top 15. This compared to values of 58.4 ml X kg-1 X min-1/10.2% and 58.7 ml X kg-1 X min-1/12.6% in the other males and females, respectively. In the 5 wk preceding competition (Hawaii "Ironman Triathlon World Championship") the average daily training of the four top 15 male competitors consisted of swimming 2720 m, running 13.6 km, and biking 84.0 km. This was approximately 1.5 times greater than that of the other athletes. The average training diet was 59% carbohydrate, 21% fat, and 20% protein. Immediately following competition, SGOT, SGPT, and serum LDH were increased 700, 262, and 222% (P less than 0.004), respectively, and still remained marginally elevated 5-6 d later (P less than 0.02). Immediately following competition, serum triglycerides remained unchanged, while serum glucose, glycerol, and nonesterified fatty acids increased 52, 248, and 191% (P less than 0.005), respectively. By 5-6 d post-competition glucose had returned to normal, while triglycerides were elevated 94% (P less than 0.005) and nonsterified fatty acids were decreased 58% (P less than 0.01).  相似文献   
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Experiences with the 5-F-"Superflow" Pigtailcatheter for transaxillary arteriography of 24 patients are reported and compared with 24 cases where a 7-F-Fr?hlich-catheter was used. The advantages of the smaller caliber for transaxillary approach are emphasized.  相似文献   
36.
BackgroundOpioid overdose-related deaths have increased dramatically in recent years. Combating the opioid epidemic requires better understanding of the epidemiology of opioid poisoning (OP) and opioid use disorder (OUD).ObjectiveWe aimed to discover geospatial patterns in nonmedical opioid use and its correlations with demographic features related to despair and economic hardship, most notably the US presidential voting patterns in 2016 at census tract level in New York State.MethodsThis cross-sectional analysis used data from New York Statewide Planning and Research Cooperative System claims data and the presidential voting results of 2016 in New York State from the Harvard Election Data Archive. We included 63,958 patients who had at least one OUD diagnosis between 2010 and 2016 and 36,004 patients with at least one OP diagnosis between 2012 and 2016. Geospatial mappings were created to compare areas of New York in OUD rates and presidential voting patterns. A multiple regression model examines the extent that certain factors explain OUD rate variation.ResultsSeveral areas shared similar patterns of OUD rates and Republican vote: census tracts in western New York, central New York, and Suffolk County. The correlation between OUD rates and the Republican vote was .38 (P<.001). The regression model with census tract level of demographic and socioeconomic factors explains 30% of the variance in OUD rates, with disability and Republican vote as the most significant predictors.ConclusionsAt the census tract level, OUD rates were positively correlated with Republican support in the 2016 presidential election, disability, unemployment, and unmarried status. Socioeconomic and demographic despair-related features explain a large portion of the association between the Republican vote and OUD. Together, these findings underscore the importance of socioeconomic interventions in combating the opioid epidemic.  相似文献   
37.
BackgroundSleeve gastrectomy (SG) has become the most prevalent bariatric-metabolic surgical approach in the United States. Its popularity among surgeons and patients is mainly due to a better safety profile and less overall morbidity, with broad benefits from a systemic and metabolic perspective.ObjectiveComprehensively describe the short-term multiorgan metabolic effects of rapid weight loss after SG.SettingAcademic hospital, United States.MethodsWe retrospectively reviewed the charts of patients that underwent SG at our institution between 2012 and 2016. We analyzed the required variables to calculate multiple risk scores, such as cardiovascular, hypertension, and diabetes risk scores. Furthermore, the renal and hepatic functions and the metabolic and hematologic profiles were assessed at 12 months of follow-up.ResultsA total of 1002 patients were included in the analysis. The percentage of excess body mass index loss was, on average, 65% at 12 months of follow-up. We observed a positive cardio-renal-hepatic improvement, demonstrated by a substantial reduction of the 10-year cardiovascular risk. We noticed an improvement of renal function, which was more significant in chronic kidney disease (stage ≥2), and a significant improvement on liver function tests (measured by decreased aspartate aminotransferase and alanine transaminase) at 12 months of follow-up. Our data also show a positive impact on decreasing the risk of developing hypertension and type 2 diabetes. There was a positive impact on the lipid profile, with the exception of low-density lipoprotein.ConclusionThere are significant short-term benefits on multiorgan metabolic parameters after rapid weight loss in severely obese patients undergoing sleeve gastrectomy.  相似文献   
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Our objective was to examine the effect of insulin-like growth factor-1 (IGF-1) on extracellular pyrophosphate (ePPi) elaboration by porcine cartilage. These studies further define the factors influencing ePPi accrual, a key step in calcium pyrophosphate dihydrate (CPPD) crystal formation. ePPi was measured in adult porcine organ and monolayer culture media in the presence of IGF-1, transforming growth factor beta-1 (TGFbeta-1), IGF-1 antibody and synovial fluid (SF). As previously shown, TGFbeta-1 stimulated ePPi elaboration by cartilage and chondrocytes. IGF-1 significantly inhibited the stimulatory effect of TGFbeta-1 on ePPi elaboration by both cartilage explants and chondrocytes. Anti-IGF-1 antibody blocked this inhibition. Anti-IGF-1 antibody also decreased the inhibitory effect of SF on ePPi elaboration, suggesting the presence of active IGF-1. These results support an important regulatory role for IGF-1 in cartilage ePPi elaboration. IGF-1 inhibited the effects of the ePPi-stimulatory factor TGFbeta-1 and thus may protect normal joints from excess accumulation of ePPi and subsequent CPPD crystal formation.  相似文献   
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