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81.

Ethnopharmacological relevance

Coriolus versicolor, which is known as Yun Zhi, is one of the commonly used Chinese medicinal herbs. Recent studies have demonstrated its antitumor activities on cancer cells which led to its widespread use in cancer patient. However, little toxicological information is available regarding its safety. The present study evaluated the potential toxicity of Coriolus versicolor standardized water extract after acute and subchronic administration in rats.

Materials and methods

In acute toxicity study, Coriolus versicolor water extract was administered by oral gavage to Sprague-Dawley (SD) rats (6 males, 6 females) at single doses of varying concentrations 1250, 2500 and 5000 mg/kg. In subchronic toxicity study, the extract was administered orally at doses of 1250, 2500 and 5000 mg/kg/day for 28 days to male and female SD rats respectively. General behavior, adverse effects and mortality were determined throughout the experimental period. Haematological and biochemical parameters, relative organ weights and histopathological were evaluated at the end of the experiment.

Results

There were no mortality and signs of toxicity in acute and subchronic toxicity studies. In the single dose acute toxicity and repeated dose 28-day subchronic toxicity studies, there were no significant difference in body weight, relative organ weight, haematological parameters, clinical chemistry, gross pathology and histopathology between treatment and control groups.

Conclusions

Coriolus versicolor water extract did not cause remarkable adverse effect in SD rats. The oral lethal dose of Coriolus versicolor water extract is more than 5000 mg/kg and no-observed-adverse-effect level (NOAEL) of the extract for both male and female rats is 5000 mg/kg per day for 28 days.  相似文献   
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ObjectivesThe aim of this study was to identify factors predictive of nursing home admission (NHA) over a period of 1 year among elderly subjects with dementia.MethodsThe study population was drawn from the SAFES cohort that was formed within a national research program into the recruitment of emergency departments in 9 teaching hospitals. Subjects were to have been hospitalized in a medical ward in the same hospital as the emergency department to which they were initially admitted. Subjects who experienced NHA before emergency department admission were excluded. Those with a confirmed diagnosis of dementia were considered in the present analysis. NHA has been defined as the incident admission into either a nursing home or other long term care facility within the follow-up period. Data obtained from a Comprehensive Geriatric Assessment were used in a Cox model to predict 1-year NHA.ResultsThe 425 subjects of the study were 86 ± 6 years old, and were mainly women (63%). NHA rate was 40% (n = 172). Four factors were identified to increase NHA risk: age 85 or older (hazard ratio [HR] = 1.5; 95% confidence interval [CI] = 1.1–2.1), inability to use the toilet (HR = 2.5; 95% CI = 1.5–4.2), balance disorders (HR = 1.5; 95% CI = 1.1–2.1), and living alone (HR = 1.5; 95% CI = 1.1–2.1). Three factors decreased this risk significantly: inability to transfer (HR = 0.5; 95% CI = 0.3–0.8), increased number of children (HR = 0.88; 95% CI = 0.96–0.99), and increased initial Mini-Mental State Examination score (HR = 0.97; 95% CI = 0.8–0.9).ConclusionNHA determinants in dementia are strongly linked to the patient’s own characteristics but also to his or her physical or social environment. Interventions should target both members of the dyad “patient-caregiver” because both are affected by the disease.  相似文献   
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The antigenic composition and protein profiles of eumycetoma agents   总被引:2,自引:0,他引:2  
The protein profiles of different eumycetoma agents were compared by SDS gel electrophoresis. Dendrograms confirmed the homogeneity of isolates of Pseudallescheria boydii but amongst Madurella species, particularly isolates identified as M. grisea, there were substantial differences in protein composition. However using Western blotting reference isolates of the different species showed distinct antigen patterns in response to immune rabbit sera. In particular there was little evidence of cross reactivity between M. mycetomatis and M. grisea. However this specificity was not apparent when human sera from patients with different eumycetoma infections were compared in an ELISA system using the same antigens. It is possible that the formation of a mycetoma grain may limit a patient's exposure to antigens which confer specificity, an explanation which may also account for the variability in antibody responses seen.  相似文献   
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OBJECTIVE: This study was undertaken to determine whether an increase in exhaled nitric oxide would reflect the severity of the acute lung injury caused by extracorporeal circulation. DESIGN: Prospective, controlled animal laboratory investigation. SETTING: University laboratory. SUBJECTS: Male, anesthetized, paralyzed, and mechanically ventilated Wistar rats (n = 34). INTERVENTIONS: Twenty-three Wistar rats underwent a partial (100 mL.kg(-1).min(-1)) femoro-femoral extracorporeal circulation in normothermia for 90 mins. Eleven time-matched rats formed the sham group. MEASUREMENTS AND MAIN RESULTS: Exhaled nitric oxide was monitored with a chemiluminescence analyzer. Acute lung injury was assessed by blood gas analysis and lung water content. Lung Evans blue dye content, lung myeloperoxidase, and heme oxygenase activities were determined. Compared with the sham rats, extracorporeal circulation was responsible for acute lung injury characterized by an increased lung water content (82.4 +/- 1.3% vs. 77.9 +/- 1.1%; p<.05), an increased Evans blue dye content (191.8 +/- 15.8 vs. 112.5 +/- 16.8 mg/g tissue wet weight; <.01), and an increased pulmonary heme oxygenase activity (332.9 +/- 107 vs. 113.7 +/- 46.5 pmol. hr(-1).mg of protein(-1); p<.05). Exhaled nitric oxide remained stable throughout the experiment in all sham rats. Among the 23 rats that underwent extracorporeal circulation, eight rats (35%) experienced an increase in exhaled nitric oxide concentration (16.9 +/- 12.7 ppb). There was no significant difference between rats that did or did not experience an increase in exhaled nitric oxide regarding each index of acute lung injury. CONCLUSIONS: An increase in exhaled nitric oxide did not reflect the severity of the acute lung injury caused by extracorporeal circulation. Its significance remains to be determined.  相似文献   
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We describe a rare case of retrosternal goiter that developed on the left side of the trachea, squeezing between the trachea and the left supra-aortic vessels, and causing signs of compression and acute left upper limb ischemia in a 35-year-old woman. Her symptoms disappeared after an emergency total thyroidectomy was performed.  相似文献   
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