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961.
BACKGROUND: Flexion-extension roentgenograms (FER) of the cervical spine are often inadequate because of limited range of motion (ROM). The purpose of this study was to determine the utility of goniometry to predict a patient's ability to achieve sufficient ROM to obtain adequate FER. METHODS: We evaluated 65 consecutive blunt trauma patients undergoing evaluation by FER in the emergency department. Patients were evaluated by goniometry before performing FER. Adequate ROM was defined as flexion and extension of >30 degrees from neutral. RESULTS: Seventy-five percent of patients had adequate FER. All of these patients were predicted to have sufficient ROM by goniometry. Goniometry predicted limited ROM in 69% of patients who had inadequate FER. The positive predicative value of goniometry in predicting inadequate FER was 100%. The incidence of cervical spine injuries was 44% in patients with inadequate ROM by goniometry and 23.0% in patients with inadequate FER (versus 7.69% in patients with adequate FER). CONCLUSION: Goniometry accurately predicted those patients who were unable to achieve sufficient ROM for adequate FER. Patients with inadequate FER were at a higher risk for cervical spine injury compared with patients with adequate FER (23.0 versus 7.69%). Early identification of these patients will help limit the number of inadequate studies obtained and expedite evaluation of high-risk patients. 相似文献
962.
Toxicity of heavy metals in soil assessed with various soil microbial and plant growth assays: a comparative study 总被引:1,自引:0,他引:1
Abstract-Elevated metal concentrations in soils can disturb the soil ecosystem; thus, researchers strive to identify the most sensitive assay for detection of the early signs of toxicity. The purpose of the present study was to compare eight different ecotoxicological endpoints on the same set of metal-contaminated soils that were collected from seven series of soils sampled during field trials. The endpoints are based on three microbial assays (potential nitrification rate [PNR], substrate-induced respiration [SIR], and basal respiration [BR]) and two plant growth tests, one of which included symbiotic N fixation. The overall sensitivity of the endpoints to detect statistically significant adverse effects ranked as follows: PNR > SIR (lag time) > plant yield and N fixation > SIR (respiration after 24 and 48 h) > BR. The lowest adverse effect concentrations were found with the PNR at 7 mg kg(-1) of Cd and 107 mg kg(-1) of Zn. The variability of these endpoints among different uncontaminated soils was additionally assessed on 14 soil samples. That variability showed a strong correlation with sensitivity scores, illustrating that metal-sensitive endpoints have a large natural variability. We question the ecological relevance of highly sensitive microbial assays, because they tend to have a large natural variability. The identification of toxicity in the field requires endpoints that are highly sensitive and that do not vary greatly among soils (i.e., robust); however, no such endpoint was found in the present study. The endpoints that combined average sensitivity and robustness were SIR (lag time), clover yield, and N fixation in clover. 相似文献
963.
Harting J van Assema P Ruland E van Limpt P Gorgels T van Ree J Vermeer F de Vries NK 《American journal of preventive medicine》2005,29(2):113-119
BACKGROUND: Although reporting on the healthcare-setting level of continuance or discontinuance of an intervention once a trial is completed has been recommended, such "real-world" diffusion studies are rare. The present example was made possible by funding to explore opportunities for post-trial implementation of an innovative health counseling intervention for cardiovascular prevention in The Netherlands. METHODS: Between 2001 and 2004, in a longitudinal case study, we compared two healthcare settings: a cardiology outpatient clinic and general practices. Rogers' diffusion of innovations theory served as the theoretical background. Information was extracted from minutes of meetings and informal conversations with health counselors, and checked by the project manager. Additional data were collected from physicians with a short questionnaire. RESULTS: Implementation of the health counseling intervention was successful in the cardiology outpatient clinic, but was unsuccessful in the general practices. Success was related to a centralized diffusion system, stronger "change agent" efforts, avoidance of post-trial interruption of service delivery, easily achievable "reinventions," and positive physician perceptions of the service (i.e., not complex and compatible with current practice routines). Support came from changes in the organization of care that created opportunities for, instead of competition with, the innovative service. However, coincidental events may also have played a part. CONCLUSIONS: Our findings confirm the importance of most theoretically predicted individual and organizational diffusion variables. This implies that the implementation of innovative healthcare services requires attention at both levels. 相似文献
964.
Bang B Aasmoe L Aamodt BH Aardal L Andorsen GS Bolle R Bøe R Van Do T Evans R Florvåg E Gram IT Huser PO Kramvik E Løchen ML Pedersen B Rasmussen T 《Journal of occupational and environmental medicine / American College of Occupational and Environmental Medicine》2005,47(5):482-492
OBJECTIVE: In this study, we explored airway symptoms and exposure to bioaerosols and exhaust gases in seafood industry plants. METHODS: The study details the results from personal and environmental exposure measurements (17 plants), a questionnaire (n = 984), and clinical examinations (n = 225). RESULTS: The workers were exposed to allergens, endotoxins, molds, and exhaust. The 1-year prevalence of work-related airway symptoms was 42.8% for production workers and 25.9% for administrative workers. Mean levels of forced expiratory volume in 1 second and forced vital capacity were less than the predicted values in all exposed nonsmoker groups. A total of 20.5% had increased levels of total IgE (>/=100 kU/L). Specific IgE-mediated reactions seemed to be relevant only in the shrimp industry. CONCLUSIONS: Seafood industry workers showed a high prevalence of work-related airway symptoms. Further research on the relationship between exposure and effects is necessary. 相似文献
965.
966.
967.
Occupational magnetic fields and female breast cancer: a case-control study using Swedish population registers and new exposure data 总被引:3,自引:0,他引:3
Several recent epidemiologic studies on occupational magnetic field exposure have suggested an association with female breast cancer. The purpose of this study was to test this hypothesis by using the extensive Swedish population registers in combination with improved exposure assessment. The study base consisted of all women between 1976 and 1999 gainfully employed in Stockholm or Gotland County in Sweden. A total of 20,400 cases of breast cancer were identified from the cancer registry, and 116,227 controls were selected randomly from the study base. Information was available on estrogen receptor status, occupation, socioeconomic status, and age. Parity was available for a subset. The exposure was assessed by linkage to a newly developed job-exposure matrix based on personal magnetic field measurements on women. All risk estimates were close to unity regardless of exposure cutpoint or choice of exposure parameter. The overall odds ratio for women exposed to 0.30 microT or more was 1.01 (95% confidence interval: 0.93, 1.10). The size of the study allowed for estimates with good precision also in subgroups where previous studies have suggested increased risk, but the findings do not support the hypothesis that magnetic fields influence the risk of female breast cancer. 相似文献
968.
Zabel EW Falken MC Sonnabend M Alms M Symonik D 《Journal of environmental health》2005,68(2):9-15, 36
The objectives of the study reported here were to determine the prevalence of elevated blood lead levels in rural Minnesota and to evaluate a lead-risk-screening questionnaire. Blood lead tests and lead risk questionnaires were obtained for a sample of 1,090 children younger than 48 months of age (72 percent of the eligible population) from three rural counties of west-central Minnesota between September 1, 2001, and August 31, 2002. It was found that overall, 2.4 percent of children in the study had blood lead levels of > or = 10 microg/dL (0.48 micromol/L) (results for capillary and venous tests combined), 0.9 percent had venous blood lead levels of > or = 10 microg/dL, and 0.5 percent of study participants had blood lead levels of > or = 20 microg/dL (0.96 micromol/L). Three risk factor questions, when taken together, predicted 90 percent of blood lead levels of > or = 10 microg/dL and all blood lead levels of > or = 20 microg/dL. The study estimated the prevalence of lead poisoning using a sample of the entire population rather than a clinic-based convenience sample. The authors conclude that targeted screening is an effective way to identify lead-poisoned children in rural areas of Minnesota. 相似文献
969.
Mala T Edwin B Rosseland AR Gladhaug I Fosse E Mathisen O 《Journal of Hepato-Biliary-Pancreatic Surgery》2005,12(4):298-303
Background/Purpose The short-term outcome following laparoscopic liver resection at a single center is presented.Methods Fifty-three procedures were carried out in 47 patients, between August 1998 and April 2004 (6 patients were resected on two occasions). A previous laparotomy and/or hepatectomy had been done in 83% and 26% of the procedures, respectively. Colorectal metastasis was the main indication for treatment (42/53). A total laparoscopic approach was applied.Results Three of the 53 (6%) procedures were converted to laparotomy. In one additional procedure, radiofrequency ablation was done instead of resection. Sixty liver resections were done during the 49 procedures completed laparoscopically as planned (9 patients had concomitant resections performed). Nonanatomic (45/60) and anatomic (15/60; left lobectomies) resections were done. Tumor tissue was found in the resection margins of 6% of the specimens. The free margin was very short in 8% of the specimens. The morbidity was 16%. There was no mortality. Blood transfusions were given following 26% of the procedures. The median hospital stay was 3.5 days (range, 1–14 days) and the median number of days on which there was a need for opioids was 1 (range, 0–11 days).Conclusions Laparoscopic liver resection can be performed safely and seems to offer short-term benefits to the patients. Randomized studies are required to further evaluate the potential benefits of this treatment. 相似文献
970.