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991.
OBJECTIVES: A surveillance program for upper-limb work-related musculoskeletal disorders (UWMSD) based on assessment of health and risk factors was implemented between 1996 and 2000 in a large shoe factory with overall high levels for biomechanical exposure. The study aimed to identify workers with an increased risk of UWMSD incidence. METHODS: In 1996, 1997 and 2000, 166 workers filled out a questionnaire and underwent a standardized physical examination. Factors from the 1996 questionnaire (general, personal and occupational factors) associated with UWMSD incidence in 1997 were selected. The predictive role of these variables was studied with a logistic model, taking into account also gender and age. The performance of a risk score based on this model was studied in 2000, using the Wilcoxon test and ROC curves. RESULTS: In 1997, 28 incident cases of UWMSD were observed (N = 107, 26.2%). Work pace and prior history of UWMSD were the only factors significantly associated with UWMSD incidence in 1997 (respectively 33% versus 13%, P = 0.02 and 58% versus 22%, P = 0.01). Psychological distress (36% versus 21%, P = 0.10), physical fatigue (35% versus 22%, P = 0.14), repetitiveness (30% versus 18%, P = 0.17) and task precision (33% versus 21%, P = 0.16) were also included in the logistic model for 1997 UWMSD incidence. Controlling for these variables, prior history of UWMSD remained associated with incidence in 1997 (OR = 5.5, 95% CI = 1.4-21.8). In the period from 1997 to 2000, 24 incident cases were observed (N = 102, 23.5%). The risk score, based on variables from the 1997 model, was significantly higher for incident cases (median = 6 in incident cases versus 4.5 for healthy subjects, P = 0.02). ROC curves indicated that the highest agreement reached 67% for sensitivity and 59% for specificity. Among subjects who did not change their task (N = 71, 18 incident cases), performance reached 66% for specificity with the same sensitivity. CONCLUSION: These results suggest that surveillance programs of UWMSD at a company level are possible even with overall high levels for biomechanical exposure and should take into account occupational and personal factors, including prior history of UWMSD.  相似文献   
992.
993.
Contact investigation is a key component of tuberculosis (TB) control in developed, but not developing, countries. We aimed to measure the prevalence of TB among household contacts of sputum-smear-positive TB cases in The Gambia and to assess the sensitivity of an enzyme-linked immunospot (ELISPOT) assay in this regard. Household contacts of adult smear-positive TB patients were assessed by questionnaire, purified protein derivative (PPD) skin test, ELISPOT assay, physical examination, chest X-ray and sputum/gastric aspirate. Thirty-three TB cases were identified from 2174 of 2381 contacts of 317 adult smear-positive pulmonary TB patients, giving a prevalence of 1518/100000. The cases identified tended to have milder disease than those passively detected. The sensitivity of ESAT-6/CFP-10 ELISPOT test as a screening test for TB disease was estimated as 71%. Fifty-six per cent of contacts with a PPD skin test result >or=10mm induration had detectable responses to ESAT-6/CFP-10 by ELISPOT; 11% with a negative PPD skin test (<10mm) had a positive ESAT-6/CFP-10 response. Active screening for TB among contacts of TB patients may have a role in TB control in The Gambia. These individuals are a high-risk group, and the disease identified is less advanced than that found through passive case detection. An ELISPOT assay was relatively insensitive as a screening test for TB.  相似文献   
994.
The transplantation of human cells and tissues has become a global enterprise for both life-saving and life-enhancing purposes. Yet current practices raise numerous ethical and policy issues relating to informed consent for donation, profit-making, and quality and safety in the procurement, processing, distribution, and international circulation of human cells and tissues. This paper reports on recent developments in the international debate surrounding these issues, and in particular on the attention cell and tissue transplantation has received in WHO's ongoing process of updating its 1991 Guiding principles on human organ transplantation. Several of the organizers of an international working group of stakeholders from a wide range of backgrounds that convened in Zurich in July 2006 summarize the areas of normative agreement and disagreement, and identify open questions regarding facts and fundamental concepts of potential normative significance. These issues must be addressed through development of common medical, scientific, legal and ethical requirements for human cell and tissue transplantation on a global basis. While guidance must accommodate the distinct ethical issues raised by activities involving human cells and tissues, consistency with normative frameworks for organ transplantation remains a prime objective.  相似文献   
995.
Canada has a long tradition of leading practice-changing clinical trials in oncology. Here, we describe methodology, results, and interpretation of oncology RCTs with Canadian involvement compared to RCTs from other high-income countries (HICs). A literature search identified all RCTs evaluating anti-cancer therapies published 2014–2017. RCTs were classified based on the country affiliation of first authors. The study cohort included 636 HIC-led RCTs; 155 (24%) had Canadian authors. Three-quarters (112/155, 72%) of Canadian RCTs were conducted in the palliative setting, compared to two thirds (299/481, 62%) of RCTs from other HICs (p = 0.022). Canadian RCTs were more likely than those from other HICs to be supported by industry (85% vs. 69%, p < 0.001). The proportion of positive Canadian trials that met the ESMO-MCBS threshold for substantial clinical benefit was comparable to RCTs without Canadian authors (29% vs. 32%, p = 0.137). Thirteen percent (20/155) of all Canadian trials were affiliated with the Canadian Cancer Trials Group (CCTG). Canada plays a meaningful role in the global cancer research ecosystem but is overly reliant on industry support. The very low proportion of trials that identify a new treatment with substantial clinical benefit is worrisome. A renewed investment in cancer clinical trials is needed in Canada.  相似文献   
996.
We conducted an analysis of indirect costs alongside the LY.12 randomized trial in patients with relapsed or refractory (R/R) aggressive non-Hodgkin lymphoma (NHL). Lost productivity data for Canadian patients and caregivers in the trial were collected at baseline and with each chemotherapy cycle pre-transplant, using an adapted Lost Productivity questionnaire. Mean per patient indirect costs were CAD 2999 for patients in the GDP arm and CAD 3400 in the DHAP arm. A substantial majority was not working or had to reduce their workload during this treatment time. Salvage chemotherapy for R/R aggressive NHL is associated with significant indirect costs to patients and their caregivers.  相似文献   
997.
BACKGROUND: Coronary artery disease (CAD) is the single largest killer of both males and females in the United States. The Emergency Department (ED) represents a unique environment in which patient education may improve coronary artery disease risk factor knowledge and relative risk perception. ED patients' understanding of CAD risk factors is often limited. Patients' perception of their own risk is often not a reflection of their true risk. We hypothesized that an American Heart Association educational video intervention would improve patients' knowledge of coronary artery disease risk factors and personal risk awareness in the ED setting. METHODS: IRB approval was obtained for this prospective observational cohort study. Our trial included 100 adult patients (age 18 and over), both male and female, using the ED population at an inner city tertiary care Level I trauma center hospital as our source of participants. Recruitment of patients began in January 2002 and ended in May 2004. RESULTS: Patients who watched the educational video did improve their knowledge of cardiac risk factors significantly when compared to patients who received no educational video intervention. In our study, this information was not retained at 30-day follow-up. However, there was still significant improvement in their knowledge when compared to baseline scores pre-intervention. Patients overestimated their risk when compared to an objective measure of risk. In both the study and control groups, patients significantly overestimated their risk pre-educational intervention, immediately post-educational intervention, and at 30-day follow-up when compared to an objective measure of risk. CONCLUSIONS: Simple educational intervention at a teachable moment (i.e. when a patient is experiencing chest pain in the ED) significantly improves patient's knowledge of CAD risk factors immediately post-intervention. This improvement in knowledge is not fully retained at 30-day follow-up, which suggests that patients may benefit from further educational intervention prior to 1 month follow-up. Patients overestimate their risk when compared to an objective measure of risk, regardless of whether they receive an educational intervention or not.  相似文献   
998.
Hawker JI  Olowokure B  Wood AL  Wilson RC  Johnson R 《Vaccine》2007,25(43):7516-7519
We examined MMR vaccine uptake among ethnic groups in Birmingham, UK between 1994 and 2000, a period incorporating adverse MMR vaccine publicity. From 1994 to 2000 overall uptake: (1) fell significantly from 91.1% in 1994 to 89.8% (chi(2) for trend p<0.001) in 2000, (2) in Asian children significantly increased (chi(2) for trend p<0.001), and (3) in White children significantly decreased (chi(2) for trend p<0.001). Differences between ethnic groups with the highest (Asian) and the lowest (Black Caribbean) uptake rates increased from 2.1% in 1994 (p=ns) to 6.8% in 2000 (p<0.001). This study suggests underlying ethnic inequalities in MMR vaccine uptake and differential response to adverse vaccine publicity.  相似文献   
999.
1000.
To determine the effect of nematode infection on the response of snails to selected toxins, we infected Helix aspersa with 0-, 0.25-, 1-, or 4-fold the recommended field dose of a commercial nematode application for agricultural use. In the first experiment, the snails also were exposed to cadmium via food and soil at concentrations of 0, 30, 60, 120, or 240 mg/kg in a full-factorial design. In the second experiment, snails were infected with nematodes and also fed either Bt (expressing Bacillus thuringiensis toxin) maize or non-Bt maize. The snails were weighed at the beginning and end (after four weeks) of the experiments, and mortality was checked daily. Neither exposure of snails to nematodes nor exposure of snails to cadmium or Bt toxin affected the survival rates of snails. The number of dead snails was highest for combinations of nematode treatments with cadmium concentrations of 120 and 240 mg/kg. In both experiments (Bt and cadmium), the growth rate decreased with increasing nematode dose. The Bt maize was not harmful to the snails in the absence of nematodes, but infected snails grew faster when fed non-Bt maize. The growth rate of snails exposed to cadmium decreased with exposure to increasing Cd concentrations and differed significantly between the no-nematode treatment and the treatments with nematode doses of one- and fourfold the recommended field dose. Snails treated with the highest dose of nematodes accumulated the highest cadmium concentrations.  相似文献   
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