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51.
Abnormal gene dosage usually results in recognizable phenotypic abnormalities, especially if it involves a series of contiguous genes. Schmickel (1986) defined contiguous gene syndromes as diseases resulting from loss or gain of a series of adjacent genes. The terms microdeletion and microduplication as well as segmental aneusomy have also been used to describe such losses or gains that may not be readily detectable by Gbanded analysis. The loss (haploinsufficiency) or gain of a series of adjoining genes may result in a direct phenotypic effect and/or cause a genetic regulatory disturbance. Such syndromic gains or losses are often detectable when in situ hybridization of fluorescent labeled DNA probes or array comparative genomic hybridization technique are used (Gersen and Keagle 2005; Stumm et al. 1999; Barch, Knutsen and Spurbeck 1997). Segmental aneusomies generally occur due to homologous pairing between non-allelic low copy repeats (LCR) followed by crossing over. The LCRs, as part of the repetitive DNA sequences range from 1-500 Kb repeats, share >97% base sequence identity and constitute up to five percent of the genomic DNA. They are distributed throughout the genome, but are more concentrated near the centromeres and telomeres. A segment of 300 bp completely identical sequence within the LCRs is adequate for mediating non-allelic homologous or paralogous pairing. This process results in generating both deletion and duplication of a defined segment.  相似文献   
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53.
The study evaluated the long-term influence of feeding ground barley treated with lactic acid (LA) alone or with LA and heat on performance, energy and protein balance in dairy cows. Thirty cows were fed three diets differing in the treatment of barley grain, either unprocessed ground barley (Control), ground barley steeped in 1% LA at room temperature (LA-treated barley) or ground barley steeped in 1% LA with an additional heating at 55°C (LAH-treated barley). Cows were studied from week 3 to 17 post-partum. Dry matter intake (DMI), milk yield and composition and body weight (BW) were measured daily. Estimated energy and protein balances were calculated and blood samples were collected three times during the experiment and analysed for common metabolites of energy and lipid metabolism. Digestibility of different treated barley and other dietary ingredients was investigated in vivo using four wethers. The treatment of barley with LA and LAH increased the digestibility of organic matter (OM) by approximately 5% and the content of metabolisable energy by 0.5–0.6 MJ/kg DM. Data showed no effect of feeding diets containing LA- or LAH-treated barley at 39% of DM on overall DMI, BW, BW change, milk production and composition and on the blood variables studied. Diet influenced the estimated balances of net energy of lactation (p < 0.01) and the content of utilisable protein at the duodenum (p = 0.07) with cows fed the diet with LA-treated barley showing improved balances. In conclusion, feeding diets containing LA- or LAH-treated barley had no influence on performance, milk composition and blood metabolites, but LA treatment without heat seems to improve the energy balance of cows.  相似文献   
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We report the synthesis, spectroscopic characterization, molecular docking and biological evaluation of nine pyrazino-imidazolinone derivatives. These derivatives were evaluated for their anticancer activity against three cancer cell lines: 518A2 melanoma, HCT-116, and HCT-116 p53 knockout mutant colon carcinoma. The MTT assay was employed to assess their effectiveness. Among the nine compounds tested, four compounds (5 a, 5 d, 5 g, and 5 h) exhibited promising antiproliferative activity specifically against HCT-116 p53-negative cells (IC50 0.23, 0.20, 2.07 and 58.75 μM, respectively). Interestingly, treatment with the 3,4-dimethoxyphenyl derivative 5a resulted in a significant increase (199 %) in caspase activity in HCT-116 p53-negative cells compared to untreated cells while the bromo-pyrazine derivative 5d demonstrated (190 %) increase. These findings suggest that compounds 5a and 5 d induce p53-independent apoptotic cell death. Additionally, in silico molecular docking studies with EGFR and tyrosinase proteins indicated that compounds 5 d and 5 e have the potential to bind to important anticancer drug targets.  相似文献   
56.
Thromboxane B2 was formed from endogenous precursors during short incubations of guinea pig and rat cerebral cortex. The amount formed by guinea pig brain tissue was 5–6 times the formation of prostaglandin F and E2. Noradrenalin stimulated and indomethacin and mercaptoethanol inhibited thromboxane B2 formation. The mass spectrum of the brain compound was identical to thromboxane B2 formed from arachidonic acid by guinea pig lung and human platelets.  相似文献   
57.
Bayesian extrapolation of space-time trends in cancer registry data   总被引:1,自引:0,他引:1  
Schmid V  Held L 《Biometrics》2004,60(4):1034-1042
We apply a full Bayesian model framework to a dataset on stomach cancer mortality in West Germany. The data are stratified by age group, year, and district. Using an age-period-cohort model with an additional spatial component, our goal is to investigate whether there is evidence for space-time interactions in these data. Furthermore, we will determine whether a period-space or a cohort-space interaction model is more appropriate to predict future mortality rates. The setup will be fully Bayesian based on a series of Gaussian Markov random field priors for each of the components. Statistical inference is based on efficient algorithms to block update Gaussian Markov random fields, which have recently been proposed in the literature.  相似文献   
58.
The distribution of silver, arsenic, cadmium, cobalt, chromium, copper, iron, manganese, nickel, lead, selenium and zinc binding to species with different molecular weight in aqueous extract of krill was studied by on-line size-exclusion chromatography (SEC)/inductively coupled plasma mass spectrometry (ICP-MS). The extract was fractionated in three fractions with different molecular weight (MW) ranges (>20,000 relative molecular mass (rel. mol. mass), 2000-20,000 rel. mol. mass and <2000 rel. mol. mass), which were further analyzed by SEC with columns having different optimum fractionation ranges in order to obtain more detailed information about the MW distribution of the elements. Various distribution profiles for the target elements among different MW ranges were observed. The results obtained indicated that manganese, zinc, silver, cadmium and lead species were mostly distributed in the higher MW range (>20,000 rel. mol. mass). In the case of chromium, iron, cobalt, arsenic and selenium, most of them bind to species with lower MW (<2000 rel. mol. mass). Only copper and nickel species was predominantly present in middle MW range (2000-20,000 rel. mol. mass). Further speciation of arsenic compounds in the small MW fraction was carried out with anion exchange chromatography (AEC) coupled with ICP-MS. The results showed that the dominant arsenic species in this fraction is As(III) (63% of extractable arsenic), while As(V) (13%) and two unknown arsenic species (19% and 5%, respectively) are present in lower amounts.  相似文献   
59.
Alterations of social cognition and dysfunctional interpersonal expectations are thought to play an important role in the etiology of depression and have, thus, become a key target of psychotherapeutic interventions. The underlying neurobiology, however, remains elusive. Based upon the idea of a close link between affective and introspective processes relevant for social interactions and alterations thereof in states of depression, we used a meta-analytically informed network analysis to investigate resting-state functional connectivity in an introspective socio-affective (ISA) network in individuals with and without depression. Results of our analysis demonstrate significant differences between the groups with depressed individuals showing hyperconnectivity of the ISA network. These findings demonstrate that neurofunctional alterations exist in individuals with depression in a neural network relevant for introspection and socio-affective processing, which may contribute to the interpersonal difficulties that are linked to depressive symptomatology.  相似文献   
60.
During the last 15 years, European stone fruit yellows (ESFY) has become a major concern in Austrian fruit production. Therefore, presence and temporal dynamics of its vector Cacopsylla pruni were investigated using a beating tray method and yellow sticky traps on Prunus armeniaca, Prunus domestica, Prunus spinosa and P. cerasifera nigra. Infection rates of C. pruni and Prunus spp. trees were assessed by direct, nested and real‐time PCR. Movement of remigrants in a model apricot orchard was tracked by aid of a mark, release and recapture study. Insects were marked by fluorescent dyes. Movement of the marked insects and presence of naturally occurring insects were monitored by yellow sticky traps. In 2011, remigration of C. pruni to Prunus spp. started in calendar week 10 (8th of March) and in 2012, in calendar week 12 (18th of March). Remigrants were observed until calendar week 20 (middle of May), significant numbers of the springtime generation adults were present until week 26 (end of June). The phytoplasma was ascertained in 0–11.5% of the remigrants and in 0–3.44% of the springtime generation insects. About 9.8–63.3% of the apricot samples, 20–40% of the plum samples and single blackthorn samples were infected. The mark, release and recapture study proved a fast and frequent tree‐to‐tree movement of remigrated C. pruni adults. Insects easily covered distances from row to row or even farther (ca. 13 m) within 24 h after release and were present in a large part of the model orchard after 8 days (up to 24 m from release point).  相似文献   
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