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Mycoplasma pneumoniae isolates from patients, collected over a period of 12 years in Germany, were characterized by various methods (parameters) including multilocus sequence typing, restriction fragment length polymorphisms, Western blotting with mono-specific antibodies directed against selected proteins or with polyspecific antibodies directed against the Triton X-114-soluble protein fraction, and two-dimensional gel electrophoresis. The results for 91 isolates from Germany, which were complemented with 14 isolates from the USA and 10 isolates from France, clearly showed that M. pneumoniae is a highly uniform species and that most of the isolates could be assigned to one of the two subtypes 1 and 2. The members of one subtype differ from the other with respect to the sequence of the P1 gene, the ORF6 gene, the P65 gene, and by a typical DNA restriction fragment pattern. We observed four isolates (variants), which seemed identical by the above mentioned criteria, but did not belong to either one of the two subtypes. They showed most of the subtype 2-specific features, but differed in the sequence of the P1 gene and showed a variation in the restriction fragment pattern. The appearance of subtype 1 or 2 over the last 12 years in Germany showed a dominance of subtype 1 between 1989 and 1996 and a dominance of subtype 2 between 1997 and 1998. The variant (neither subtype 1 nor subtype 2) was only detected in 1991 and 1995 but it had no epidemiological consequences.  相似文献   
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Summary The uptake of 14C-choline into the axonal part of the motor endplate and muscle of mouse diaphragms was investigated by autoradiography. With i. v. doses of 0.1 g/g choline chloride, the uptake into the nerve endings is fast (<2 min) and into muscle slower (>2 min). With higher doses (1.0 g/g) the uptake into muscle tissue is accelerated.The radioactivity in the endplates decreases with a halflife time of 20 min and remains constant in the muscle fibres over 60 min. Denervation by cutting the phrenic nerve reduces the uptake into endplates by 40% within 14 h, but probably induces uptake into regenerating Schwann cells during 30 days. Some compounds with choline-like structure (hemicholinium-3, decamethylen-dicholine, triethyl-choline) reduce the high-affinity uptake of choline into the nerve endings with sublethal doses, whereas tetraethylammonium and N-hydroxyethyl-4-(1-naphthylvinyl)-pyridinium, an inhibitor of cholinacetyltransferase, are less active. Half lethal doses of cocaine, imipramine and reserpine have no significant action on uptake of choline into the endplates. Chlorpromazine slightly diminishes the uptake into endplates. Chlorpromazine and imipramine reduce uptake into the muscle fibres.  相似文献   
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Antidepressants have been associated with weight gain, but the causes are unclear. The aims of this study were to assess the association of antidepressant use with energy intake, macronutrient diet composition, and physical activity. We used data on medication use, energy intake, diet composition, and physical activity for 3073 eligible adults from the 2005–2006 National Health and Nutrition Examination Survey (NHANES). Potential confounding variables, including depression symptoms, were included in the models assessing energy intake, physical activity, and sedentary behavior. Antidepressant users reported consuming an additional (mean ± S.E.) 215 ± 73 kcal/day compared to non-users (p = 0.01). There were no differences in percent calories from sugar, fat, or alcohol between the two groups. Antidepressant users had similar frequencies of walking or biking, engaging in muscle-strengthening activities, and engaging in moderate or vigorous physical activity. Antidepressant users were more likely to use a computer for ≥2 h/day (OR 1.77; 95% CI: 1.09–2.90), but TV watching was similar between the two groups. These results suggest increased energy intake and sedentary behavior may contribute to weight gain associated with antidepressant use. Focusing on limiting food intake and sedentary behaviors may be important in mitigating the weight gain associated with antidepressant use.  相似文献   
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Objectives: To document how race and ethnicity are identified, categorized, and utilized in contemporary dental public health literature. Methods: Two researchers independently performed a literature review of all articles in Community Dentistry and Oral Epidemiology and the Journal of Public Health Dentistry over a 5‐year period (2004‐2009). Articles pertaining to the study of US‐based populations with any mention of race or ethnicity were included. The following data were abstracted from each article: a) how each article broadly described race and/or ethnicity; b) the terms used to specifically define the races and/or ethnicities captured; c) the location of any mention of the concept of race and/or ethnicity; d) the stated purpose for including race and/or ethnicity concepts; e) the stated analytic use of race and/or ethnicity concepts; and f) the stated method used to assess race and/or ethnicity concepts. Results: Overall, race and/or ethnicity concepts were most commonly referred to within the text of the results section. Fifty percent of articles did not state their purpose for including race and/or ethnicity concepts within their studies, while 34.3 percent omitted stating their analytic use of these concepts. When assessing these concepts, 41.4 percent relied upon subject self‐report. Conclusion: These data showed that there was inconsistent documentation of how race and ethnicity was measured. While race and ethnicity are important measures for public health studies and are frequently reported in dental public health research, there is no clear system for classifying these measures.  相似文献   
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OBJECTIVE: To compare the diagnostic accuracy of contrast medium enhanced spiral computed tomography of the pulmonary arteries (s-CTPA) and a latex agglutination D-dimer assay in patients with suspected acute pulmonary embolism (PE) by using pulmonary arteriography (PA) and clinical follow-up as reference method. DESIGN: Ninety hemodynamically stable patients with symptoms of acute pulmonary embolism were prospectively evaluated with s-CTPA and pulmonary arteriography (PA) within 24 h from admission. Plasma D-dimer levels on admittance were analyzed using a rapid latex agglutination D-dimer assay. The outcome of D-dimer concentrations in plasma below 0.25 and 0.5 mg/l was studied. RESULTS: All PA and s-CTPA investigations were regarded as of acceptable diagnostic quality in a consensus reading. Thirty-three patients had a positive PA (37%). Three patients had false negative and two patients had false positive s-CTPA findings. s-CTPA had 91% sensitivity, 96% specificity, 94% positive predictive value (PPV) and 95% negative predictive value (NPV). The sensitivity and specificity for D-dimer below 0.5 mg/l were 79 and 88%, respectively. The PPV and NPV were 81 and 87%. If a cut-off level of 0.25 mg/l was used the corresponding figures were 91, 65, 63 and 92%. CONCLUSION: s-CTPA has a higher sensitivity and specificity than latex agglutination D-dimer. A cut-off level of 0.25 mg/l can be used as screening method, but s-CTPA must be performed to exclude false positive cases.  相似文献   
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BACKGROUND: Instruments that measure the impact of illness on work do not usually provide a measure that can be directly translated into lost hours or costs. We describe the validation of the Work and Health Interview (WHI), a questionnaire that provides a measure of lost productive time (LPT) from work absence and reduced performance at work. METHOD: A sample (n = 67) of inbound phone call agents was recruited for the study. Validity of the WHI was assessed over a 2-week period in reference to workplace data (i.e. absence time, time away from call station and electronic continuous performance) and repeated electronic diary data (n = 48) obtained approximately eight times a day to estimate time not working (i.e. a component of reduced performance). RESULTS: The mean (median) missed work time estimate for any reason was 11 (8.0) and 12.9 (8.0) hours in a 2-week period from the WHI and workplace data, respectively, with a Pearson's (Spearman's) correlation of 0.84 (0.76). The diary-based mean (median) estimate of time not working while at work was 3.9 (2.8) hours compared with the WHI estimate of 5.7 (3.2) hours with a Pearson's (Spearman's) correlation of 0.19 (0.33). The 2-week estimate of total productive time from the diary was 67.2 hours compared with 67.8 hours from the WHI, with a Pearson's (Spearman's) correlation of 0.50 (0.46). CONCLUSION: At a population level, the WHI provides an accurate estimate of missed time from work and total productive time when compared with workplace and diary estimates. At an individual level, the WHI measure of total missed time, but not reduced performance time, is moderately accurate.  相似文献   
9.
BACKGROUND: Intra-arterial chemotherapy is an effective modality to treat unresectable hepatic metastases from colorectal primaries if systemic chemotherapy has failed. Response rates of more than 40% and a median survival of 15 to 25 months have been reported from randomized trials. In this retrospective study, we analyzed specific technical complications associated with continuous intra-arterial chemotherapy for colorectal liver metastases. METHODS: From 1982 to 1995, single-center clinical data from 180 patients with colorectal liver metastases were evaluated. Continuous intra-arterial chemotherapy was administered using either an implanted infusion pump or an intra-arterial port with an external infusion pump. The intra-arterial catheter was implanted according to the Watkins' technique. The treatment protocols consisted of 5-fluorouracil- or 5-fluorodeoxyuridine-based regimens. RESULTS: A total of 70 patients (39%) received an intra-arterial infusion pump and 110 patients (61%) an intra-arterial port. Sixty-eight technical complications affected port systems (62%), whereas 29 patients with pumps (41%) were affected by technical complications. Therapy-relevant complications were observed in 47% of the ports and 30% of the infusion pumps. The median complication-free survival was 12.2 months for infusion pumps and 7.3 months for ports (P =.0016). CONCLUSIONS: Our data demonstrate that pumps are superior to ports in terms of complication rate and complication-free survival. On the basis of our results, pumps have a potential for a longer treatment, which may result in a prolonged median survival.  相似文献   
10.
The American Productivity Audit (APA) is a telephone survey of a random sample of 28,902 U.S. workers designed to quantify the impact of health conditions on work. Lost productive time (LPT) was measured for personal and family health reasons and expressed in hours and dollars. Health-related LPT cost employers 225.8 billion US dollars/year (1685 US dollars/employee per year); 71% is explained by reduced performance at work. Personal health LPT was 30% higher in females and twice as high in smokers (> or =1 pack/day) versus nonsmokers. Workers in high-demand, low-control jobs had the lowest average LPT/week versus the highest LPT for those in low-demand, high-control jobs. Family health-related work absence accounted for 6% of all health-related LPT. Health-related LPT costs are substantial but largely invisible to employers. Costs vary significantly by worker characteristics, suggesting that intervention needs vary by specific subgroups.  相似文献   
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