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Of 86 patients with inoperable malignant dysphagia, 68 (79 per cent) underwent successful palliation by endoscopic laser therapy, of whom 24 remained well palliated until the time of death. In 18 patients laser treatment was unsuccessful and nine of these underwent intubation, eight successfully. After successful laser therapy, dysphagia recurred in 44 patients a mean of 7.8 weeks later. Of these, 31 received palliation until death by dilatation with or without laser therapy, and 13 required intubation. The overall laser-related complication rate was 12 per cent with a mortality rate of 4 per cent. The intubation-related mortality rate was 9 per cent.  相似文献   
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BACKGROUND: Optical penalization (OP) has previously been shown to successfully maintain vision in amblyopic eyes of older children when patching compliance is poor and when vision decreases once patching is discontinued. This study shows that the final vision in optically penalized eyes is often better than the vision obtained after patching alone. SUBJECTS AND METHODS: During the 5-year period from January 1992 to February 1997, 28 children aged between 3.7 and 8.2 years (average age, 6.5+/-1.1 years) were optically penalized for an average of 1.5+/-0.75 years. The maximum length of penalization was 3.3 years, whereas the minimum time was 6 months. There were 21 children with strabismic amblyopia and 7 children with anisometropic amblyopia. All 28 children had worn a patch to achieve their best visual levels and then had shown a loss of best vision when occlusion was stopped. Patching was usually resumed and continued until the previous best vision was obtained; at this point OP was started to "maintain" vision. Eighteen of the 28 children have discontinued penalization and have been followed up an average of 1(1/2) years. RESULTS: Twenty-six (93%) of the 28 patients showed an increase in best vision from that found at the conclusion of patching, and 2 patients maintained their vision at the initial level. The average visual acuity at the start of penalization was 20/50 (0.42+/-0.11 logarithm of the minimum angle of resolution [log MAR]). Final average visual acuity was 20/27 (0.15+/-0.12 log MAR). The average increase in vision was nearly 3 lines or 0.27+/-0.12 log MAR. CONCLUSION: OP alone (without the use of pharmacologic agents such as atropine) not only maintains vision after patching therapy, but also appears to improve the final visual outcome.  相似文献   
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STUDY OBJECTIVE--The aim was to establish the public's perception of the relative importance of various environmental risk factors for cancer. DESIGN--A postal survey was undertaken using a questionnaire to assess the public's knowledge of cancer morbidity and mortality and the role of lifestyle and genetic risk factors. Sociodemographic data were also collected. SETTING--The survey was completed in the state of South Australia. PARTICIPANTS--A random sample of 1500 names were selected from the electoral rolls of the state. These rolls contain the names of all Australian citizens over the age of 18 years. A response rate of 73% was achieved. MEASUREMENTS AND MAIN RESULTS--The results of the survey showed that the knowledge base of the community was generally high, with few differences across sociodemographic groups. The relative importance of cancer as a contributor to mortality was, however, overestimated and the potential for "cure" underestimated. The role of both diet and cigarette smoking in cancer promotion was widely recognised but there was an overemphasis on the importance of pollution of the food supply compared to imbalance of nutrients. Respondents were more able to assign risk in relation to diet using a food based assessment, compared to a nutrient approach. There was wide acceptability that lifestyle change could have a profound effect on the cancer profile of the community. CONCLUSIONS--With the relatively high degree of awareness and acceptance of lifestyle factors as cancer risk determinants, campaigns which involve skill transfer and removal of barriers to change would appear to be the most relevant approach to improvement in community behaviour.  相似文献   
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目的:筛选一株优良的抗生素产生菌。方法:通过人为诱变来动摇产生菌原有的严密控制机制。结果:得到一种抗生素生物合成能力异常的突变株。结论:此方法可过量合成人们所期望的抗生素。  相似文献   
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目的:考察盐酸特拉唑嗪胶囊的稳定性。方法:通过影响因素(强光照射、高温、高温),加速和留样考察实验,以含量为测定指标,考察胶囊的含量变化。结果:在温度40℃、60℃、光照3500LX及RH75%等因素影响下,胶囊的含量无明显变化。结论:在25℃时,通过经典恒温加速试验推测盐酸特拉唑嗪胶囊的失效期为2年。  相似文献   
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This study examined the effects of an anti-smoking campaign that employs a crowdsourcing method with a social networking service. Drawing upon social capital scholarship and the expression effect research paradigm in eHealth systems, the study also investigated the roles of social trust and community life satisfaction in the social media campaign that has a specific geographical boundary. To that end, we conducted an experiment using a two-group pretest–posttest design. We randomly assigned 201 participants to two conditions: “campaign message reception only” as a control group and “message reception and expression” as a treatment group in which participants fully engaged in the campaign process by sharing their own campaign ideas with other participants. Findings revealed that social trust and community life satisfaction interacted with the treatment condition to positively affect persuasive intentions, but in distinct ways. Social trust moderated the effect of the message reception and interaction condition on participants’ willingness to encourage community members to stop smoking. In contrast, community life satisfaction moderated the effect of the treatment condition on encouraging others to comply with the community’s anti-smoking policy. These results provide theoretical and practical implications related to the roles of social capital in geographically defined social media campaigns.  相似文献   
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Distal ulcerative colitis can be treated with oral or rectal mesalazine, or both. A foam enema preparation has been developed and its efficacy investigated. The aim of this study was to evaluate the efficacy and safety of mesalazine foam enemas compared with prednisolone foam enemas in the treatment of patients with acute distal ulcerative colitis. Patients aged over 18 years presenting with a relapse of distal ulcerative colitis were randomly allocated treatment with mesalazine foam enema (n = 149 evaluable patients) and prednisolone foam enema (n = 146 evaluable patients) for four weeks. A randomised multicentre investigator blind parallel group trial was conducted. It was found that after four weeks of treatment, clinical remission was achieved by 52% of mesalazine treated patients and 31% of patients treated with prednisolone (p < 0.001). There was a trend in favour of more patients in the mesalazine group achieving sigmoidoscopic remission (40% v 31%, p = 0.10). Histological remission was achieved by 27% and 21% of patients receiving mesalazine and prednisolone respectively. Symptoms improved in both treatment groups. Significantly more mesalazine patients had no blood in their stools after four weeks of treatment (67% v 40%, p < 0.001). Prednisolone treated patients had significantly fewer days with liquid stools than mesalazine patients, with a median of 0 and 1 days respectively by week 4 (p = 0.001). In this study mesalazine foam enema was superior to prednisolone foam enema with regards to clinical remission, this was supported by favourable trends in sigmoidoscopic and histological remission rates. Both treatments were well tolerated.  相似文献   
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