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101.
The roots and rhizomes of licorice (Glycyrrhiza) species have long been used worldwide as a herbal medicine and natural sweetener. Licorice root is a traditional medicine used mainly for the treatment of peptic ulcer, hepatitis C, and pulmonary and skin diseases, although clinical and experimental studies suggest that it has several other useful pharmacological properties such as antiinflammatory, antiviral, antimicrobial, antioxidative, anticancer activities, immunomodulatory, hepatoprotective and cardioprotective effects. A large number of components have been isolated from licorice, including triterpene saponins, flavonoids, isoflavonoids and chalcones, with glycyrrhizic acid normally being considered to be the main biologically active component. This review summarizes the phytochemical, pharmacological and pharmacokinetics data, together with the clinical and adverse effects of licorice and its bioactive components.  相似文献   
102.
Objective  The purpose of this study was to determine a possible relation between exposure to extremely low frequency magnetic field (ELF-MF) and the human antioxidant activity. Methods  The total serum antioxidant status (TAS), red blood cells (RBCs) glutathione peroxidase (GPX) and superoxide dismutase (SOD) were measured in 46 spot welders who were occupationally exposed to ELF-MF (magnetic field strength = 8.8–84 microTesla (μT), frequency = 50 Hertz (Hz) and electric field strength = 20–133 V/m). The results were compared with a nonexposed ELF-MF control group. The correlation between magnetic field strength and antioxidant activity in RBCs and plasma was then assessed. Results  No significant differences in TAS levels were observed (P value = 0.065). However, in RBCs of exposed group, a significant decrease in SOD and GPX activities was observed (P value = 0.001 and 0.003, respectively). This decrease was measured as 22 and 12.3%, respectively. Furthermore, a significant negative correlation between SOD/GPX activities and magnetic field intensity was observed (coefficients of SOD: −0.625, significance: 0.0001 and coefficients of GPX: −0.348, significance: 0.018). Conclusion  The results of this study indicate that ELF-MF could influence the RBC antioxidant activity and might act as an oxidative stressor. Intracellular antioxidant enzymes such as SOD and GPX were found to be the most important markers involving in this process. The influence of magnetic field on the antioxidant activity of RBCs might occur even at the recommended levels of exposure.  相似文献   
103.
Background: Poor nutrition status is considered a risk factor for postoperative complications in the adult population. In elderly patients, who often have a poor nutrition status, this relationship has not been substantiated. Thus, the aim of this systematic review was to assess the merit of preoperative nutrition parameters used to predict postoperative outcome in elderly patients undergoing general surgery. Methods: A systematic literature search of 10 consecutive years, 1998–2008, in PubMed, EMBASE, and Cochrane databases was performed. Search terms used were nutrition status, preoperative assessment, postoperative outcome, and surgery (hip or general), including their synonyms and MeSH terms. Limits used in the search were human studies, published in English, and age (65 years or older). Articles were screened using inclusion and exclusion criteria. All selected articles were checked on methodology and graded. Results: Of 463 articles found, 15 were included. They showed profound heterogeneity in the parameters used for preoperative nutrition status and postoperative outcome. The only significant preoperative predictors of postoperative outcome in elderly general surgery patients were serum albumin and ≥10% weight loss in the previous 6 months. Conclusions: This systematic review revealed only 2 preoperative parameters to predict postoperative outcome in elderly general surgery patients: weight loss and serum albumin. Both are open to discussion in their use as a preoperative nutrition parameter. Nonetheless, serum albumin seems a reliable preoperative parameter to identify a patient at risk for nutrition deterioration and related complicated postoperative course.  相似文献   
104.
Slovenia is a small, fast developing country in the EU with approximately 2,000,000 inhabitants and 700,000 employed. Occupational medicine has been present in Slovenia for as long as 500 yr. Today, 130 specialists of occupational medicine are in charge of health protection of the employed (including transport workers and athletes). There are also 1,100 safety engineers, who take care of the technical side of occupational safety. We are guided in our work by modern occupational health and safety legislation, which is based on EU directive 89/391EEC. The average sick leave rate in Slovenia is about 4.7%, caused mostly by injuries, bone, muscle and connective tissue diseases and respiratory diseases. Sick leave appears most frequently in the textile industries and coal mining. Annually, around 26,000 occupational injuries (32.7 per 1,000 employed) and 25 fatalities (3 per 100,000 employed) occur. Most injuries occur in construction, manufacturing and farming. Each year there are 8,500 disablility cases (2,500 disability retirements-most caused by mental illnesses), but only 30 acknowledged cases of occupational diseases (mostly occupational skin diseases, asthma and asbestosis). Occupational medicine in Slovenia is strongly associated with occupational medicine in the more developed European countries. It is therefore moving out of clinics and into the working environment, where its goals lie in primary prevention, i.e. establishing and keeping healthy working environments that guarantee high productivity, health and well-being of workers as a whole.  相似文献   
105.
Background Occupational, environmental, or experimental exposure of people, animals, and cell cultures to radon has been the subject of numerous studies. The present study comprised 120 miners, occupationally exposed to radon and heavy metals in a Pb-Zn mine; 57 female subjects environmentally exposed (control group 1); and 100 subjects from the urban population (control group 2). Methods Radon measurements were performed, and the effective equivalent radiation doses over a 2-year period were calculated. The following end points were studied: conventional analysis of structural chromosomal aberrations, micronuclei, and sister chromatid exchanges (SCE). Results The mean values of the percentage of structural chromosomal aberration frequency were 4.09% in miners, 1.43% in control group 1, and 1.88% in control group 2. The difference in frequencies was statistically significant (AV/FP 0.000). The frequency of micronuclei was 13.00 ± 3.54 per 500 CB cells in miners and 6.4 ± 2.11 per 500 CB cells in control subjects (AV/FP 0.000). The frequency of SCE was 7.97 per cell in miners (range 6.2–13.1) and 6.17 and 6.63 for the two control groups, respectively (AV/FP 0.000). Conclusions Comparative analysis of the cytogenetic results for all three groups showed significant differences between the miners and the two control groups. The findings of this study need to be interpreted with regard to simultaneous exposure to radon and metals, i.e., lead, cadmium, and zinc. Am. J. Ind. Med. 34:455–463, 1998. © 1998 Wiley-Liss, Inc.  相似文献   
106.
Metabolic syndrome (MS) is a highly prevalent health problem worldwide and is associated with different risk factors, including hyperglycemia, dyslipidemia, hypertension, and obesity. This condition increases the risk of developing type II diabetes mellitus and cardiovascular problems. The MS is one of the most important health concerns in industrialized countries and mainly results from a sedentary lifestyle, high levels of subjective stress, and unhealthy diets. Nowadays, the identification of appropriate health care approaches, such as herbal medicines, with fewer side effects is more favorable, especially with regard to the adverse effects of chemical drugs. Aloe barbadensis Miller known as Aloe vera is a useful plant with two major parts, including leaves that contain high concentrations of anthraquinone compounds and a clear gel. The gel is used as a food with several beneficial properties, such as antiinflammatory, antioxidant, antiviral, antibacterial, and wound‐healing features. Other effects of A. vera, such as its lipid‐lowering, antihypertensive, antidiabetic, antiobesity, and cardioprotective impacts, have been demonstrated in several studies. The present study was conducted to review the evidence on the pharmacological effects of A. vera on the different components of MS.  相似文献   
107.
BACKGROUND: The purpose of this study was to describe the health status and work limitations in injured workers with musculoskeletal disorders at 1 month post-injury, stratified by return-to-work status, and to document their return-to-work trajectories 6 months post-injury. METHODS: A sample of 632 workers with a back or upper extremity musculoskeletal disorder, who filed a Workplace Safety and Insurance Board lost-time claim injury, participated in this prospective study. Participants were assessed at baseline (1 month post-injury) and at 6 months follow-up. RESULTS: One month post-injury, poor physical health, high levels of depressive symptoms and high work limitations are prevalent in workers, including in those with a sustained first return to work. Workers with a sustained first return to work report a better health status and fewer work limitations than those who experienced a recurrence of work absence or who never returned to work. Six months post-injury, the rate of recurrence of work absence in the trajectories of injured workers who have made at least one return to work attempt is high (38%), including the rate for workers with an initial sustained first return to work (27%). CONCLUSIONS: There are return-to-work status specific health outcomes in injured workers. A sustained first return to work is not equivalent to a complete recovery from musculoskeletal disorders.  相似文献   
108.
Background Response shift has gained increasing attention in the measurement of health-related quality of life (QoL) as it may explain counter-intuitive findings as a result of adaptation to deteriorating health. Objective To search for response shift type explanations to account for counter-intuitive findings in QoL measurement. Methods Qualitative investigation of the response behaviour of small-cell lung cancer (SCLC) patients (n = 23) in the measurement of fatigue with The European Organization for Research and Treatment of Cancer Core Quality of Life Questionnaire (EORTC QLQ-C30) question ‘were you tired’. Interviews were conducted at four points during 1st line chemotherapy: at the start of chemotherapy, 4 weeks later, at the end of chemotherapy, and 6 weeks later. Patients were asked to ‘think aloud’ when filling in the questionnaire. Results Fifteen patients showed discrepancies between their answer to the EORTC question ‘were you tired’ and their level of fatigue spontaneously reported during the interview. These patients chose the response options ‘not at all’ or ‘a little’ and explained their answers in various ways. In patients with and without discrepancies, we found indications of recalibration response shift (e.g. using a different comparison standard over time) and of change in perspective (e.g. change towards a more optimistic perspective). Patients in the discrepancy group reported spontaneously how they dealt with diagnosis and treatment, i.e. by adopting protective and assertive behaviour and by fighting the stigma. They distanced themselves from the image of the stereotypical cancer patient and presented themselves as not suffering and accepting fatigue as consequence of treatment. Conclusion In addition to response shift, this study suggests that ‘self-presentation’ might be an important mechanism affecting QoL measurement, particularly during phases when a new equilibrium needs to be found.  相似文献   
109.
CONTEXT: Continuous assessment of individual performance of doctors is crucial for life-long learning and quality of care. Policy-makers and health educators should have good insights into the strengths and weaknesses of the methods available. The aim of this study was to systematically evaluate the feasibility of methods, the psychometric properties of instruments that are especially important for summative assessments, and the effectiveness of methods serving formative assessments used in routine practise to assess the performance of individual doctors. METHODS: We searched the MEDLINE (1966-January 2006), PsychINFO (1972-January 2006), CINAHL (1982-January 2006), EMBASE (1980-January 2006) and Cochrane (1966-2006) databases for English language articles, and supplemented this with a hand-search of reference lists of relevant studies and bibliographies of review articles. Studies that aimed to assess the performance of individual doctors in routine practise were included. Two reviewers independently abstracted data regarding study design, setting and findings related to reliability, validity, feasibility and effectiveness using a standard data abstraction form. RESULTS: A total of 64 articles met our inclusion criteria. We observed 6 different methods of evaluating performance: simulated patients; video observation; direct observation; peer assessment; audit of medical records, and portfolio or appraisal. Peer assessment is the most feasible method in terms of costs and time. Little psychometric assessment of the instruments has been undertaken so far. Effectiveness of formative assessments is poorly studied. All systems but 2 rely on a single method to assess performance. DISCUSSION: There is substantial potential to assess performance of doctors in routine practise. The longterm impact and effectiveness of formative performance assessments on education and quality of care remains hardly known. Future research designs need to pay special attention to unmasking effectiveness in terms of performance improvement.  相似文献   
110.
Infectious mononucleosis (IM), resulting from Epstein-Barr virus (EBV) infection, and IM-like syndromes, mainly due to cytomegalovirus (CMV), Toxoplasma gondii, or human immunodeficiency virus (HIV), have been occasionally reported in travelers returning from the tropics. Our objective was to investigate the prevalence, outcome, and diagnostic predictors of these syndromes in febrile travelers. Between April 2000 and March 2005, all febrile travelers and migrants presenting at our referral centers within 12 months after a tropical stay were prospectively included. We identified all patients serologically diagnosed with IM or IM-like syndrome and compared them with the rest of the cohort. During the 5-year period, 72/1,842 patients (4%) were diagnosed with an IM-like syndrome, including 36 CMV, 16 T gondii, 15 EBV, and 5 HIV primary infections. All patients were western travelers or expatriates. Mean delay before consultation was 2 weeks. Most patients had consulted other practitioners and/or received presumptive treatment. A minority of patients presented with IM clinical features. Lymphocytosis > or =40% of the white blood cells (WBC) and reactive/atypical lymphocyte morphology were observed in 60 and 30% of the patients. The four diseases were indistinguishable. Protracted fever and asthenia were common but complications rarely occurred. IM-like syndromes were independently associated with fever >7 days, lymphadenopathy, elevated liver enzymes, and lymphocytosis > or =40% of WBC. Diagnostic probability increased to >20% if at least three of these predictors were present. Diagnosis of IM and IM-like syndrome is not uncommon in febrile travelers, with a higher proportion of primary CMV, T gondii, and HIV infections than in nonimported series. Consequently, classic IM clinical and laboratory features are often lacking. All four pathogens should be systematically considered because early diagnosis should avoid unnecessary investigations and treatment and allow early intervention in case of primary HIV infection.  相似文献   
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