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There is increasing global pressure to ensure that pregnant women are responsibly and safely included in clinical research in order to improve the evidence base that underpins healthcare delivery during pregnancy. One supposed barrier to inclusion is the assumption that pregnant women will be reluctant to participate in research. There is however very little empirical research investigating the views of pregnant women. Their perspective on the benefits, burdens and risks of research is a crucial component to ensuring effective recruitment. The Research In Pregnancy Ethics (RIPE) study set out to ascertain the views of pregnant women about research participation using an inductive thematic analysis. We conducted semi‐structured interviews with 20 women who had participated in a double‐blind randomised placebo controlled trial in Wellington (New Zealand) while pregnant. Our results show that at least some pregnant women recognise the value and importance of research during pregnancy. The women we interviewed were deeply invested in the research process and outcomes. Key motivations for participating were altruism, playing a valuable civic role and the importance of research. The main perceived burdens related to inconvenience and time commitment. For some women, possible randomization to the placebo arm was regarded as a burden or disadvantage.  相似文献   
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Non-steroidal anti-inflammatory drugs have been accused of causing false positive results in faecal occult blood tests for colorectal cancer. A study was therefore performed in 10,931 people undergoing faecal occult blood screening tests to assess the effect of these drugs on the predictive value of a positive test result. Those with a positive result were interviewed and a full drug history was taken before they underwent a full colorectal examination. Of the 455 people with a positive result, 50 were taking non-steroidal anti-inflammatory drugs: 10 (20%) had colonic neoplasia. Of the 405 who were not taking non-steroidal anti-inflammatory drugs, 129 (32%) had colonic neoplasia. These detection rates were not significantly different, and the predictive value of a positive result for an adenoma larger than 1 cm was 14% in the group not taking anti-inflammatory drugs and 26% in the group taking them (not significant). These results suggest that a finding of occult faecal blood cannot be attributed to upper gastrointestinal tract bleeding caused by non-steroidal anti-inflammatory drugs and should be followed by a thorough colorectal examination.  相似文献   
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Ubiquitin-specific protease 9, Y-linked (USP9Y), is a protein encoded by the Y chromosome. Its precise function in the cell is unknown, although a role in the regulation of protein turnover has been postulated. Nonetheless, mutations in this gene could result in the over- or under-abundance of proteins involved in the regulation of spermatogenesis. We have identified a novel mutation, SM1, located in exon 25 of USP9Y (c.3642G→A), which results in an amino acid substitution (p.V1214I). The mutation is in close linkage (four bases distant) from a silent mutation, referred to as M222 (p.E1212E, c.3636G→A). In our male population (n = 374), SM1 was found in one individual (0.3%) who belongs to the recently described haplogroup R1b3h, defined by the U152 SNP. This new mutation is expected to represent a new haplogroup, (R1b1c10a); therefore, within our population of individuals from haplogroup R1b3h (R1b110) (n = 16), it has a frequency of 6.3% (95% CI: 2.7–9.9%).  相似文献   
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Sex allocation theory has proved extremely successful at predicting when individuals should adjust the sex of their offspring in response to environmental conditions. However, we know rather little about the underlying genetics of sex ratio or how genetic architecture might constrain adaptive sex-ratio behavior. We examined how mutation influenced genetic variation in the sex ratios produced by the parasitoid wasp Nasonia vitripennis. In a mutation accumulation experiment, we determined the mutability of sex ratio, and compared this with the amount of genetic variation observed in natural populations. We found that the mutability (h(2)(m)) ranges from 0.001 to 0.002, similar to estimates for life-history traits in other organisms. These estimates suggest one mutation every 5-60 generations, which shift the sex ratio by approximately 0.01 (proportion males). In this and other studies, the genetic variation in N. vitripennis sex ratio ranged from 0.02 to 0.17 (broad-sense heritability, H(2)). If sex ratio is maintained by mutation-selection balance, a higher genetic variance would be expected given our mutational parameters. Instead, the observed genetic variance perhaps suggests additional selection against sex-ratio mutations with deleterious effects on other fitness traits as well as sex ratio (i.e., pleiotropy), as has been argued to be the case more generally.  相似文献   
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