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We compared short-term indicators for service mammography screening in Europe. Data were available from 17 programmes, although not all programmes provided a comprehensive reporting. More than 90% of the target population had been screened within the last 3 years in the WE trial, whereas only two-thirds of women in England and Copenhagen had been screened within the last 3 years, which will delay or reduce the effect of screening compared with the trial. Participation was highest in sparsely populated areas. Detection rates at first screen reached three times the baseline in Copenhagen, the Netherlands and North-West England. The clinical characteristics of screen-detected cases were badly reported. Given their importance for the long-term effect of screening, further data are warranted. Sensitivity and specificity could be measured only indirectly; they showed, however, considerable variation between programmes. Fyn, Florence and Stockholm had succeeded in combining high specificity with high sensitivity. With different recall policies, different proportions of women will experience a false-positive test; expected numbers after three screens were 14%, 10% and 1%, for England, Copenhagen and the Netherlands, respectively. Based on the observed wide variation in short-term indicators, a similar wide variation is expected in the effect of screening on breast cancer mortality.  相似文献   
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Novelty processing can transform short-term into long-term memory. We propose that this memory-reinforcing effect of novelty could be explained by mechanisms outlined in the "synaptic tagging hypothesis." Initial short-term memory is sustained by a transient plasticity change at activated synapses and sets synaptic tags. These tags are later able to capture and process the plasticity-related proteins (PRPs), which are required to transform a short-term synaptic change into a long-term one. Novelty is involved in inducing the synthesis of PRPs [Moncada D, et al. (2011) Proc Natl Acad Sci USA 108:12937-12936], which are then captured by the tagged synapses, consolidating memory. In contrast to novelty, stress can impair learning, memory, and synaptic plasticity. Here, we address questions as to whether novelty-induced PRPs are able to prevent the loss of memory caused by stress and if the latter would not interact with the tag-setting process. We used water-maze (WM) training as a spatial learning paradigm to test our hypothesis. Stress was induced by a strong foot shock (FS; 5 × 1 mA, 2 s) applied 5 min after WM training. Our data show that FS reduced long-term but not short-term memory in the WM paradigm. This negative effect on memory consolidation was time- and training-dependent. Interestingly, novelty exposure prevented the stress-induced memory loss of the spatial task and increased BDNF and Arc expression. This rescuing effect was blocked by anisomycin, suggesting that WM-tagged synapses were not reset by FS and were thus able to capture the novelty-induced PRPs, re-establishing FS-impaired long-term memory.  相似文献   
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Hippocampal long‐term potentiation (LTP) is a cellular model of learning and memory. An early form of LTP (E‐LTP) can be reinforced into its late form (L‐LTP) by various behavioral interactions within a specific time window (“behavioral LTP‐reinforcement”). Depending on the type and procedure used, various studies have shown that stress differentially affects synaptic plasticity. Under low stress, such as novelty detection or mild foot shocks, E‐LTP can be transformed into L‐LTP in the rat dentate gyrus (DG). A reinforcing effect of a 2‐min swim, however, has only been shown in (Korz and Frey (2003) J Neurosci 23:7281–7287; Korz and Frey (2005) J Neurosci 25:7393–7400; Ahmed et al. (2006) J Neurosci 26:3951–3958; Sajikumar et al., (2007) J Physiol 584.2:389–400) so far. We have reinvestigated these studies using the same as well as an improved recording technique which allowed the recording of field excitatory postsynaptic potentials (fEPSP) and the population spike amplitude (PSA) at their places of generation in freely moving rats. We show that acute swim stress led to a long‐term depression (LTD) in baseline values of PSA and partially fEPSP. In contrast to earlier studies a LTP‐reinforcement by swimming could never be reproduced. Our results indicate that 2‐min swim stress influenced synaptic potentials as well as E‐LTP negatively. © 2013 Wiley Periodicals, Inc.  相似文献   
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Background:

In 2006, the National Health Service Bowel Cancer Screening Programme in England (NHSBCSP) began offering routine population-based biennial faecal occult blood testing (FOBt) at ages 60–69. There is, however, limited information on how characteristics of individuals affect participation and outcomes of screening, and we studied this association by linking NHSBCSP data to a large prospective cohort of women.

Methods:

Electronic linkage of the NHSBCSP and Million Women Study records identified 899 166 women in the study cohort with at least one invitation for screening. NHSBCSP provided information on screening acceptance, FOBt results, screen-detected colorectal cancer and other outcomes. The Million Women Study provided prospectively collected information on personal and lifestyle factors. Multiple regression was used to estimate relative risks (RRs) of factors associated with acceptance and outcomes of screening.

Results:

Overall, 70% of women (628 976/899 166) accepted their first invitation for bowel cancer screening, of whom 9133 (1.5%) were FOBt-positive, 743 (0.1%) had screen-detected colorectal cancer and 3056 (0.5%) had screen-detected colorectal adenoma. Acceptance was lower in women from the most than the least deprived tertile, in South Asians and in Blacks than in Whites, in current than in never smokers and in obese than in normal weight women: adjusted RRs (95% confidence interval) for acceptance vs not, 0.90 (0.90–0.90); 0.77 (0.75–79); 0.94 (0.92–0.96); 0.78 (0.77–0.78); and 0.88 (0.88–0.89), respectively: P<0.001 for each. These factors were also associated with an increased risk of being FOBt-positive and of having screen-detected adenoma, but were not strongly associated with the risk of screen-detected colorectal cancer. Relative risks for screen-detected adenoma were 1.22 (1.12–1.34), 2.46 (1.75–3.45), 1.61 (1.05–2.48), 1.53 (1.38–1.68) and 1.77 (1.60–1.95), respectively (P<0.001 for all, except for Blacks vs Whites P=0.03). Use of hormone therapy for menopause was associated with reduced risk of screen-detected adenoma, RR ever vs never use, 0.87 (0.81–0.93), P<0.001 and colorectal cancer, 0.78 (0.68–0.91), P=0.001.

Interpretation:

Among women in England, socioeconomic and lifestyle factors strongly affect participation in routine bowel cancer screening, risk of being FOBt-positive and risk of having screen-detected colorectal adenoma. However, screen-detected colorectal cancer risk is not strongly related to these factors.  相似文献   
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In this study, the phase development in the cement system α-TCP-OCP with phosphoric acid as a setting liquid was studied. The most promising formulation of α-TCP (60?wt%) and OCP (40?wt%) is proposed. This cement has the following characteristics: setting time 10?min, pH?=?6.7, the compressive strength about 30?MPa, and high dissolution rate in an isotonic solution; the final wt% composition of α-TCP/DCPD/HA/OCP equals 27/38/20/15. Energy dispersive X-ray diffraction techniques were used for in situ monitoring of the processes taking place in the cement in real time.  相似文献   
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