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1.
OBJECTIVE: To describe how women interpret their experiences of diagnosis and treatment of a cervical abnormality and how healthcare services for such women can be improved. DESIGN: Qualitative study using detailed individual interviews. SETTING: Australian gynaecology clinics. SUBJECTS: 29 Women who had a cervical cytological abnormality and who attended a gynaecologist. MAIN OUTCOME MEASURES: Women''s views on their diagnosis and their information needs. RESULTS: Most women wanted to participate in decisions about their care but found it difficult to get the information they required from doctors because they were confused by what their doctors told them and felt unable to ask questions in the consultation. Medical terms such as wart virus and precancer were difficult to understand. Not being able to see their cervix also made it hard for women to understand what their abnormality meant and what treatment entailed. Most women tried to make sense of their abnormality in the context of their everyday lives. For some women their gynaecological care was not consistent with the way they understood their abnormality. CONCLUSIONS: The inherent power structure of medical practice combined with time pressures often make it difficult for doctors to give the detailed information and reassurance patients need when a diagnosis is distressing or when investigation and treatment are strange and upsetting.  相似文献   
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Poly(5-fluoro-2′-deoxyuridylic acid) was synthesized and its properties were compared with those of poly(dT) and poly(dU). It readily complexed with poly(dA). The 1:1 complex melted at about 20°C lower than poly(dA) · poly(dT). A triple-stranded helix, poly(dA)·2 poly(dF5U) was formed only in high salt (2.0 M NaCl).  相似文献   
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A THE-1 sequence in intron 7 of the human dystrophin gene has been found to represent a new subfamily of THE-1 elements. The sequence is closely related to the MstII family of repetitive sequences and is more like single-copy sequences found in the galago genome than any other THE-1 sequence previously reported. This new THE-1 sequence has been compared with two other complete THE-1 sequences and three related long-terminal repeat elements that we have previously found in intron 7 of the dystrophin gene, and with members of the same family from elsewhere in the primate genome. Parsimony and deletion analysis show that the cluster of THE-1 sequences in intron 7 of the dystrophin gene has arisen from at least three individual insertion events, rather than from the insertion and duplication of a single progenitor sequence. Correspondence to: G.B. Petersen  相似文献   
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The synthesis of a high-molecular-weight, putatively all-syn DNA analogue, poly(8-bromo-2′-deoxyadenylic acid), is described. The syn → anti transition was shown to be both salt and temperature dependent. Conditions were found which favored ‘normal’ Watson-Crick pairing and duplex formation with poly(dT).  相似文献   
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Calves were either isolated, spatially but not visually, or group-reared for eight months and then kept together. Rank orders based upon competitive interactions were similar at eight and 20 months. Almost all group-reared animals were higher in rank than all isolation-reared animals. The most frequent nearest neighbour associations were between group-reared animals especially those from the same rearing group. Also frequent at eight months were associations between calves which had been isolated in adjacent pens. Isolation-reared animals associated infrequently with group-reared animals and spent more time alone. Body weight was not correlated with rearing conditions or with behavioural measures. Increase, or decrease, in rank between eight and 20 months was associated with faster, or slower, than average weight gain.  相似文献   
8.

Background

Adenocarcinomas of the ampulla of Vater are classified as biliary cancers, though the exact epithelium of origin for these cancers is not known. We sought to molecularly classify ampullary adenocarcinomas in comparison to known adenocarcinomas of the pancreas, bile duct, and duodenum by gene expression analysis.

Methods

We analyzed 32 fresh-frozen resected, untreated periampullary adenocarcinomas (8 pancreatic, 2 extrahepatic biliary, 8 duodenal, and 14 ampullary) using the Affymetrix U133 Plus 2.0 genome array. Unsupervised and supervised hierarchical clustering identified two subtypes of ampullary carcinomas that were molecularly and histologically characterized.

Results

Hierarchical clustering of periampullary carcinomas segregated ampullary carcinomas into two subgroups, which were distinctly different from pancreatic carcinomas. Non-pancreatic periampullary adenocarcinomas were segregated into two subgroups with differing prognoses: 5 year RFS (77% vs. 0%, p = 0.007) and 5 year OS (100% vs. 35%, p = 0.005). Unsupervised clustering analysis of the 14 ampullary samples also identified two subgroups: a good prognosis intestinal-like subgroup and a poor prognosis biliary-like subgroup with 5 year OS of 70% vs. 28%, P = 0.09. Expression of CK7+/CK20- but not CDX-2 correlated with these two subgroups. Activation of the AKT and MAPK pathways were both increased in the poor prognostic biliary-like subgroup. In an independent 80 patient ampullary validation dataset only histological subtype (intestinal vs. pancreaticobiliary) was significantly associated with OS in both univariate (p = 0.006) and multivariate analysis (P = 0.04).

Conclusions

Gene expression analysis discriminated pancreatic adenocarcinomas from other periampullary carcinomas and identified two prognostically relevant subgroups of ampullary adenocarcinomas. Histological subtype was an independent prognostic factor in ampullary adenocarcinomas.  相似文献   
9.
Despite much research, gaps remain in knowledge about the potential health effects of exposure to radiofrequency (RF) fields. This study investigated the effects of early‐life exposure to pulsed long term evolution (LTE) 1,846 MHz downlink signals on innate mouse behavior. Animals were exposed for 30 min/day, 5 days/week at a whole‐body average specific energy absorption rate (SAR) of 0.5 or 1 W/kg from late pregnancy (gestation day 13.5) to weaning (postnatal day 21). A behavioral tracking system measured locomotor, drinking, and feeding behavior in the home cage from 12 to 28 weeks of age. The exposure caused significant effects on both appetitive behaviors and activity of offspring that depended on the SAR. Compared with sham‐exposed controls, exposure at 0.5 W/kg significantly decreased drinking frequency (P ≤ 0.000) and significantly decreased distance moved (P ≤ 0.001). In contrast, exposure at 1 W/kg significantly increased drinking frequency (P ≤ 0.001) and significantly increased moving duration (P ≤ 0.005). In the absence of other plausible explanations, it is concluded that repeated exposure to low‐level RF fields in early life may have a persistent and long‐term effect on adult behavior. Bioelectromagnetics. 2019;40:498–511. © 2019 The Authors. Bioelectromagnetics Published by Wiley Periodicals, Inc.  相似文献   
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We extend the game theoretic model of kleptoparasitism introduced by Broom and Ruxton (1998, Behav. Ecol. 9, 397–403) in two ways: we allow for asymmetric contests, where the probability α of the challenger winning can take any value from 0 to 1; and we allow the handler to choose not to resist the challenge, but to immediately concede and relinquish its food to the challenger. We find, in general, three possible evolutionarily stable strategies—challenge-and-resist (Hawk), challenge-but-do-not-resist (Marauder) and do-not-challenge-but-resist (Retaliator). When α = 1/2, we find that Hawk and Marauder are the only ESS’s, in contrast to the result of the original model; we also find an overlap region, in parameter space, where two different ESS’s are possible, depending on initial conditions. For general α, we see that all three ESS are possible, depending on different values of the environmental parameters; however, as the average time of a contest over food becomes long, then the Marauder strategy becomes more and more prevalent. The model makes a potentially significant prediction about animal behaviour in the area of kleptoparasitism, that a searcher, when it meets a handler, will only decline to attack that handler when α < 1/2 i.e.when the defender is more likely to win. One possible converse of this statement, that a handler whose probability of success is greater than 1/2 should always resist a challenge, is not true.  相似文献   
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