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1.
A. Cattapan K. Browne D.M. Halperin A. Di Castri P. Fullsack J. Graham J.M. Langley B.A. Taylor S.A. McNeil S.A. Halperin 《Vaccine》2019,37(2):289-295
Introduction/Hypothesis
Recruitment of participants into phase 1 vaccine clinical trials can be challenging since these vaccines have not been used in humans and there is no perceived benefit to the participant. Occasionally, as was the case with a phase 1 clinical trial of an Ebola vaccine in Halifax, Canada, during the 2014–2016 West African Ebola virus outbreak, recruitment is less difficult. In this study, we explored the motivations of participants in two phase 1 vaccine trials that were concurrently enrolling at the same centre and compared the motivations of participants in a high-profile phase 1 Ebola vaccine trial to those in a less high-profile phase 1 adjuvanted seasonal influenza vaccine study.Methods
An online survey which included participants’ prior experience with clinical trials, motivations to participate (including financial incentives), and demographic information was developed to examine the motivations of healthy participants in two phase 1 clinical vaccine trials conducted at the Canadian Center for Vaccinology in Halifax, Nova Scotia. Participants were invited via email to complete the online survey. Readability and clarity were assessed through pilot testing.Results
A total of 49 (55.7%) of 88 participants of the two studies completed the survey (22 [55%] of 40 participants from the Ebola vaccine study and 27 [56.3%] of 48 from the adjuvanted influenza vaccine study). Motivations that were most frequently ranked among participants' top three in both trials were (1) wanting to contribute to the health of others, (2) wanting to participate in something important, (3) wanting to contribute to the advancement of science, and (4) wanting to receive an incentive such as money or a tablet.Conclusions/Recommendations
Although media attention and financial compensation were more often cited by Ebola vaccine trial participants as a reason to participate, both altruistic and self-interested factors were important motivations for participants in their decision to participate in a phase 1 vaccine clinical trial. 相似文献2.
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AM Manganoni† C Farisoglio† G Tucci† F Facchetti‡ PG Calzavara Pinton† 《Journal of the European Academy of Dermatology and Venereology》2007,21(10):1333-1336
BACKGROUND: Development of more than one primary melanoma in a patient is a relatively uncommon but well-recognized phenomenon. Its frequency has ranged from 1.2% to 8.2% in several series. This subgroup of patients with multiple primary lesions has not been characterized sufficiently. We report the experience of the Melanoma Unit of University Hospital Spedali Civili of Brescia, Italy. METHOD: Study subjects were drawn from 1240 patients with histologically confirmed melanoma, including melanoma in situ. From this group, multiple melanomas developed in 47 patients (3.79%). Every one of our patients has been taught to perform self-examination of the skin to detect suspicious pigmented lesions. RESULTS: Of the 47 patients described in this study, 38 had two primary melanomas, 7 had three melanomas and 2 had 5 and 10 melanomas, respectively. Mean age at first diagnosis was 46.2 years. The majority of subsequent melanomas (74.5%) were removed within 5 years of the initial operation. Synchronous lesions were found in 10 patients. In male patients, the lesion appeared most frequently on the trunk; in female patients, melanoma appeared mostly on the lower extremities. The second primary melanomas developed in the same anatomic region from the first in 53.2% of our patients. The proportion of in situ to invasive melanomas was greater for the second melanomas compared with the first melanomas. Regarding invasive melanomas, the mean thickness of the first melanomas was 1.31 mm compared with 0.66 mm for the second ones. Dividing patients into two groups, of more and less than 50, it is highlighted that in older patients synchronous lesions appear more frequently (36.4% vs. 8.0%); the median time interval between sequential melanomas is longer (84 vs. 63.7 months); and the ratio between the primary and secondary melanoma mean thickness is lower (1.21 : 1.08 vs. 1.43 : 0.63 mm). CONCLUSIONS: The study confirms that second primary melanoma is usually thinner than the first lesion, and it is more common in the same region of the body as the initial melanoma. The highest risk for a second melanoma is during the first 5 years, but a much longer time interval of 28 years is possible. Continued medical follow-up with complete skin examinations seems prudent, but it is very important to promote self-skin evaluation in patients to detect not only metastases but also subsequent primary melanomas in their earliest phases. 相似文献
7.
Posterior chamber intraocular lenses in a series of 75 autopsy eyes. Part I: Loop location 总被引:1,自引:0,他引:1
D J Apple S B Park K H Merkley R N Brems S C Richards K E Langley K L Piest R A Isenberg 《Journal of cataract and refractive surgery》1986,12(4):358-362
Over a period of 27 months, November 1983 to February 1986, 75 eyes obtained postmortem with posterior chamber intraocular lenses (IOLs) were examined at the Center for Intraocular Lens Research, University of Utah Health Sciences Center. These IOLs were studied by histopathological techniques to determine the location of the loops. The most common combination, found in 47% of the specimens, was one loop in the lens capsular sac (bag) and one loop in the ciliary sulcus. In 32% of the specimens, both loops were in the capsular sac; in 17%, both loops were in the ciliary sulcus. Compared to results observed in other autopsy studies, in which capsular fixation was documented in less than 3% of cases, these findings reflect a trend toward capsular sac (in-the-bag) implantation of open-looped posterior chamber IOLs. 相似文献
8.
J. Langley E. McLoughlin 《Burns : journal of the International Society for Burn Injuries》1988,14(6):435-439
Difficulties and bonuses of evaluating injury prevention programmes are illustrated by reference to an evaluation of the New Zealand's Children's Nightclothes Act 1977. It is demonstrated that despite the difficulties encountered in that evaluation, and the equivocal results, there were significant bonuses which more than justified the resources devoted to the evaluation. The paper is presented in an attempt to encourage others to evaluate thermal injury countermeasures who may be hesitant to do so because of the difficulties they foresee. 相似文献
9.
In eighteen patients with fulminant hepatic failure (FHF), in grade III or IV coma, both protein C antigen and activity were significantly decreased (0.35 +/- 0.03 u/ml and 0.35 +/- 0.03 u/ml respectively). There was a significant correlation between protein C antigen and activity (r = 0.61, p less than 0.01). Protein C antigen levels were inversely correlated with prothrombin time (r = -0.57, p less than 0.05) as were protein C activity levels (r = -0.57, p less than 0.05). There was also significant correlations between fibrinogen and protein C antigen (r = 0.69, p less than 0.01) and protein C activity (r = 0.61, p less than 0.01). These results demonstrate that the naturally occurring inhibitor of coagulation, protein C, is present at low levels in FHF and this is probably due to the lack of synthesis of the protein in the damaged liver. The low levels of protein C may make these patients more susceptible to the disseminated intravascular coagulation which is known to occur in FHF and this in turn will lead to a further reduction in protein C levels. 相似文献
10.
M G Long J E Boultbee R Langley E S Newlands R H Begent K D Bagshawe 《British journal of cancer》1992,66(5):883-887
The haemodynamics of the uterine arteries and myometrium were assessed using Doppler ultrasound in forty consecutive patients requiring treatment for invasive mole and choriocarcinoma. The investigations were performed prior to the commencement of chemotherapy and the subjects followed prospectively. The Doppler waveforms from the uterine arteries were analysed using the pulsatility index. It was found that patients with a pulsatility index of 1.1 or less were significantly more likely to develop drug resistance than those with a higher value (P < 0.04). There was no significant association between the pulsatility index and metastatic disease or uterine bleeding. Five out of eight patients who developed drug resistance could have avoided initial inadequate treatment if the Doppler findings were included in the scoring system for selecting chemotherapy for these tumours. It can be concluded that assessment of the uterine arteries using the pulsatility index prior to the treatment of patients with invasive mole and choriocarcinoma is of help in predicting those who will develop drug resistance. 相似文献