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Production of wood pellets is a relatively new and expanding industry in which the exposure profiles differ from those in other wood-processing industries like carpentries and sawmills where there are lower levels of wood dust. Sixty-eight personal exposure measurements of wood dust (inhalable and total dust) and resin acids were collected for 44 participants at four production plants located in Sweden. Results were used to estimate within- and between-worker variability and to identify uniformly exposed groups and determinants of exposure. In addition, overexposure, whether the risk of the long-term mean exposure of a randomly selected worker exceeding the occupational exposure limit is acceptably low, was calculated as well as the underestimation of the exposure-response relationship (attenuation). Greater variability in exposure between work shifts than between workers was observed with the within-worker variation accounting for 57-99% of the total variance in the individual-based model. Several uniformly exposed groups were detected but were mostly associated with a between-worker variation of zero which is an underestimation of the between-worker variation but an indication of uniformly exposed groups. Cleaning was identified as a work task that increases exposure slightly; so reducing workers' exposure during this operation is advisable. The levels of wood dust were high and were found to pose unacceptable risks of overexposure at all plants for inhalable dust and at three out of four plants for total dust. These findings show that exposure to dust needs to be reduced in this industry. For resin acids, the exposure was classed as acceptable at all plants. According to an individual-based model constructed from the data, the level of attenuation was high, and thus there would be substantial bias in derived dose-response relationships.  相似文献   
64.
Intra-aortic balloon pump (IABP) is commonly used as a cardiac assist device in various clinical situations: cardiogenic shock, mechanical complications of acute myocardial infarction, high risk percutaneous coronary interventions, coronary artery bypass graft surgery and refractory unstable angina and ventricular arrhythmias as bridge to therapy. Although current data support its safety, there is limited or no support for its efficacy. We present the case of spinal cord infarction after IABP use in a patient who presented with ST elevation myocardial infarction and cardiac arrest and we discuss the potential mechanism of such a devastating complication.  相似文献   
65.
BACKGROUND: Resistance to clinically important antimicrobial agents, particularly fluoroquinolones and macrolides, is increasing among Campylobacter isolates, but few studies have explored the human health consequences of such resistance. METHODS: In a registry-based cohort study, we determined the risk of invasive illness and death associated with infection with quinolone- and erythromycin-resistant Campylobacter strains, while adjusting for comorbidity. We linked data from the Danish Surveillance Registry for Enteric Pathogens with data from the Civil Registration System and National Health Registries. RESULTS: Of 3471 patients with Campylobacter infection, 22 (0.63%) had an adverse event, defined as invasive illness or death, within 90 days of the date of receipt of samples. Patients infected with quinolone-resistant Campylobacter strains had a 6-fold increased risk of an adverse event within 30 days of the date of receipt of samples, compared with patients infected with quinolone- and erythromycin-susceptible Campylobacter strains (adjusted odds ratio [AOR], 6.17 [95% confidence interval {CI}, 1.62-23.47]). However, infection with erythromycin-resistant strains was associated with a >5-fold risk of an adverse event within 90 days of the date of receipt of samples (AOR, 5.51 [95% CI, 1.19-25.50]). CONCLUSIONS: The present study provides evidence of the human health consequences of resistance to clinically important agents among Campylobacter infections and the need for increased efforts to mitigate such resistance.  相似文献   
66.
Fibroblast low density lipoprotein (LDL) plasma membrane receptor activity, measured as 125I-LDL association (plasma membrane binding plus intracellular accumulation) and degradation was determined in cell strains from 14 monozygotic (MZ) and 21 like-sexed dizygotic (DZ) normolipidemic twin pairs. The twins were between 57 and 62 years old and had liver apart for an average of 38 years (range 0-60). The intrapair differences were significantly smaller in MZ than in DZ twin pairs in fibroblast 125I-LDL association as well as degradation assays (P less than 0.05). These findings suggest a genetic influence on normal variation in LDL receptor activity in vitro. In two MZ pairs discordant for psoriasis, the psoriatic twin had markedly lower LDL receptor activity than the cotwin.  相似文献   
67.
During a 15-day experiment, weanling rats fed a 10% casein diet adulterated daily by one of four aversive taste stimuli ate 12–16% less than their controls fed ad lib on the unadulterated diet. They also demonstrated an inhibition in feed efficiency (g body weight gain/g food intake) during the first 8 days. A second control group, pair-fed to the group receiving the adulterated diet, also showed a reduction in feed efficiency. By Day 9, a compensatory process was evident in the rats fed the unpalatable diet such that feed efficiency increased above that observed for the ad lib control group. By the end of the experiment all three groups exhibited the same efficiency. The ratio of urinary nitrogen to total nitrogen intake was higher in rats fed the unpalatable diet ad lib compared to those offered the unadulterated diet ad lib. This observation suggests that the rats on the unpalatable diet were using more of the dietary protein as a caloric source than were their controls.  相似文献   
68.
Novel therapies capable of reducing myocardial infarct (MI) size when administered prior to reperfusion are required to prevent the onset of heart failure in ST‐segment elevation myocardial infarction (STEMI) patients treated by primary percutaneous coronary intervention (PPCI). Experimental animal studies have demonstrated that mineralocorticoid receptor antagonist (MRA) therapy administered prior to reperfusion can reduce MI size, and MRA therapy prevents adverse left ventricular (LV) remodeling in post‐MI patients with LV impairment. With these 2 benefits in mind, we hypothesize that initiating MRA therapy prior to PPCI, followed by 3 months of oral MRA therapy, will reduce MI size and prevent adverse LV remodeling in STEMI patients. The MINIMISE‐STEMI trial is a prospective, randomized, double‐blind, placebo‐controlled trial that will recruit 150 STEMI patients from four centers in the United Kingdom. Patients will be randomized to receive either an intravenous bolus of MRA therapy (potassium canrenoate 200 mg) or matching placebo prior to PPCI, followed by oral spironolactone 50 mg once daily or matching placebo for 3 months. A cardiac magnetic resonance imaging scan will be performed within 1 week of PPCI and repeated at 3 months to assess MI size and LV remodeling. Enzymatic MI size will be estimated by the 48‐hour area‐under‐the‐curve serum cardiac enzymes. The primary endpoint of the study will be MI size on the 3‐month cardiac magnetic resonance imaging scan. The MINIMISE STEMI trial will investigate whether early MRA therapy, initiated prior to reperfusion, can reduce MI size and prevent adverse post‐MI LV remodeling.  相似文献   
69.
A twelve-year series of 375 patients with gastric carcinoma has been studied. Primary tumours were classified as intestinal type (58%) or diffuse (26%), whereas 16% were unclassifiable. The relative age and sex incidence rates of intestinal type and diffuse gastric carcinoma were estimated using the age and sex distribution of individuals in Norway as the basis for calculation. There was no difference in the rates of diffuse gastric carcinoma between the sexes. On the other hand, the rate of men with intestinal type carcinoma was more than twice as high as that of women. This difference was consistent within each age group from adolescence to senescence. The findings indicate that Laurén's two types of gastric carcinoma are aetiologically different. The rates of both types increased with age up to the 70-79 age group, whereas the rates in octogenarians tended to be lower than in septuagenarians. A comparison of our data with the data of incidence of gastric cancer in Norway indicates that some of the older patients do not come for surgery.  相似文献   
70.
BACKGROUND: A better treatment modality is needed to control the pain of medial or lateral epicondylitis (tennis elbow). HYPOTHESIS: Dermal iontophoretic administration of dexamethasone sodium phosphate will be significantly more effective in controlling pain than a placebo in patients with medial or lateral elbow epicondylitis. STUDY DESIGN: Randomized, double-blinded, placebo-controlled study. METHODS: On six occasions, 1 to 3 days apart within 15 days, 199 patients with elbow epicondylitis received 40 mA-minutes of either active or placebo treatment. RESULTS: Dexamethasone produced a significant 23-mm improvement on the 100-mm patient visual analog scale ratings, compared with 14 mm for placebo at 2 days and 24 mm compared with 19 mm at 1 month. More patients treated with dexamethasone than those treated with placebo scored moderate or better on the investigator's global improvement scale (52% versus 33%) at 2 days, but the difference was not significant at 1 month (54% versus 49%). Investigator-rated pain and tenderness scores favored dexamethasone over placebo at 2 days. Patients completing six treatments in 10 days or less had better results than those treated over a longer period. CONCLUSIONS: Iontophoresis treatment was well tolerated by most patients and was effective in reducing symptoms of epicondylitis at short-term follow-up.  相似文献   
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