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31.
This paper describes the epidemiology of unintentional carbon monoxide (CO) poisoning in Northwest Iran between 2003 and 2008. Data were obtained from the records of the main provider of emergency medical transportation and from death certificate reports of the Legal Medicine Organization. During the study period, a total of 3078 hospital admissions were recorded against which 346 deaths were due to unintentional CO related poisoning caused by gas appliances in the homes. The ratio of unintentional CO related poisoning cases in relation to all poisonings was 11.6%. With regard to gender differences, non-fatal CO poisoning was higher in females than males, whereas actual fatalities were higher in males than females. Non-fatal CO poisoning was most prevalent in adults aged between 20 and 49 years, whereas the age specific death rate was highest for those over 60 years. The highest frequency of both non-fatal poisonings and actual fatalities occurred in the month January. The results suggest that CO poisoning has a high prevalence in this geographic region, with elderly adults being at the greatest risk, especially during the winter season. This represents a serious, but often neglected area of public health, and Health Authorities should be encouraged to promote public awareness against the dangers of CO exposure. This paper reviews the data and evidence surrounding the issue of CO poisoning and makes recommendations that a range of agencies and authorities should be involved in setting stricter standards and environmental legislations in this respect.  相似文献   
32.
Saffron (dried stigmas of Crocus sativus L.) has been used as a spice, food colorant and medicinal plant for millennia. In this study cytotoxic effect of saffron extract was evaluated in HepG2 and HeLa cell lines. Meanwhile role of apoptosis and ROS were explored. Malignant and non-malignant cells (L929) were cultured in DMEM medium and incubated with different concentrations of ethanolic saffron extract. Cell viability was quantitated by MTT assay. Apoptotic cells were determined using PI staining of DNA fragmentation by flow cytometry (sub-G1 peak). ROS was measured using DCF-DA by flow cytometry analysis. Saffron could decrease cell viability in malignant cells as a concentration and time-dependent manner. The IC50 values against HeLa and HepG2 were determined 800 and 950 μg/ml after 48 h, respectively. Saffron induced a sub-G1 peak in flow cytometry histogram of treated cells compared to control indicating apoptotic cell death is involved in saffron toxicity. This toxicity was also independent of ROS production. It might be concluded that saffron could cause cell death in HeLa and HepG2 cells, in which apoptosis or programmed cell death plays an important role. Saffron could be also considered as a promising chemotherapeutic agent in cancer treatment in future.  相似文献   
33.
Varying titres of secretory IgA antibodies to poliovirus type 1 were found previously in the milk of unvaccinated, lactating Pakistani mothers during two different years, reflecting the antigenic exposure on mucosal membranes. To study further the changes in the extent and the form of antigenic exposure reflected in the human milk, human milk samples from Pakistani, Indian, Japanese, and Swedish mothers were collected. The quality and the neutralising capacity of the antibodies was also studied. Secretory IgA, IgG, and IgM antibodies to poliovirus type 1 were determined using enzyme linked immunosorbent assay (ELISA) and relative affinity was measured in ELISA by elution with potassium thiocyanide. Microneutralisation tests were also performed. The higher secretory IgA antibody titres to poliovirus type 1 in the unvaccinated, naturally exposed Pakistani and Indian mothers' milk, compared with the Swedish and Japanese mothers, presumably reflect the epidemiological situation in these countries. Neutralising capacity and the relative antibody affinity seemed to be higher both in the Pakistani mothers and the group without natural exposure but only given inactivated poliovirus vaccine, that is the Swedish mothers, than the group meeting only live vaccine strains, that is the Japanese mothers.  相似文献   
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Among extracorporeal liver support devices, liver dialysis is cleared by the U.S. Food and Drug Administration to be used for the management of fulminant hepatic failure (FHF). The outcomes of patients following liver dialysis need to be clearly evaluated. Among the 25 patients with FHF admitted to the Liver ICU between May 2000 and November 2002, 12 underwent liver dialysis, including 6 men and 6 women, of mean age 32 years. The causes of FHF were identified as acetaminophen (n = 10), herbal medications (n = 1) and autoimmune disease (n = 1). At presentation, the mean total bilirubin was 9.35 mg/dL (range, 0 to 1.3), mean ALT 3015 U/L (range, 0 to 48), mean AST 3457 (range, 0 to 42), mean ammonia 98 micromol/L (range, 10 to 60) and mean INR 1.88. A control group including 13 patients (2 men and 11 women), of mean age 27.8 years mean total bilirubin 5.66, mean ALT 3494, mean AST 3528, mean ammonia 113 and mean INR 3, were not treated with liver dialysis, due to the lack of machine availability or physician's choice. The causes of FHF were acute hepatitis B (n = 1), acetaminophen (n = 10) or unknown (n = 2). There was no statistically significant difference in the baseline characteristics of the two groups (P >.05). Among the liver dialysis group, 1 patient died, 2 underwent OLTx, and 9 were discharged home. Among the control group; 4 patients died, 2 underwent OLTx, and 7 were discharged home. Preliminary results seem to support survival benefit among patients who underwent liver dialysis compared to non-liver dialysis; however, further randomized control trials are warranted to verify this observation.  相似文献   
36.
BACKGROUND AND OBJECTIVE: Recurrence of atrial flutter (AFl) on antiarrhythmic drugs is frequently observed. To determine the reasons for drug inefficacy, the electrophysiological parameters of AFl were studied in eight patients without drug, six patients on sotalol (Sot), eight patients on amiodarone (Amio) and four patients on propafenone (PPF) who presented to the electrophysiology laboratory for conversion of AFl by rapid atrial pacing. METHODS: A quadripolar electrode catheter was positioned in the right atrium in the pathway of the AFl circuit. The duration and composition of the excitable gap (EG) were determined by premature stimuli during AFl. RESULTS: The EG in AFl recurring on Sot (80 +/- 25 ms), Amio (78 +/- 13 ms) and PPF (83 +/- 26 ms) was not significantly different from that without drug (88 +/- 14 ms). Furthermore, a fully excitable portion of the EG was present whether with or without drug. CONCLUSIONS: AFl recurrence on Amio, PPF or Sot is associated with the continued presence of an EG and fully excitable portion. These findings explain the persistent viability of the AFl circuit despite drug therapy in these patients.  相似文献   
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38.
Angiosarcoma is a rare type of breast cancer, it has the worst prognosis of all breast malignancies. We report three cases of breast angiosarcoma observed at the National Oncology Institute and the Maternity of Orangers. A preoperative diagnosis was evoked in one case only, after a local recurrence in the second one and histological in the last one. Mastectomy is the reference treatment. The development is distinguished by general metastasis. Based on review of literature, we analysed the different aspects of this disease.  相似文献   
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The immunohistochemical expression of p16 in formalin-fixed and paraffin-embedded histological sections was evaluated in a retrospective study comprising a low-grade group of 100 cases of cervical intraepithelial neoplasia (CIN) 1, a high-grade group of 50 cases of CIN 2 to 3, and a benign group of 50 cases of normal tissue or benign lesions in the uterine cervix. The cases were consecutive within each group and had a minimum follow-up period of 5 years. Positive reaction for p16 was detected in all cases in the high-grade group and in only 3 cases in the benign group. In the low-grade group, a total of 9 cases had to be excluded. The remaining 91 cases in the low-grade group showed positive reaction for p16 in 65 cases (71%), including 23 cases that progressed to a high-grade lesion, 36 cases that revealed normal cytological and/or histological picture during the follow-up period, and 6 cases that persisted as CIN 1. A total of 26 cases (29%) in the low-grade group showed negative reaction for p16. All but one of these p16 negative cases in the low-grade group had a benign or normal outcome. This case showed a high-grade lesion in the follow-up period and was probably a high-grade lesion from the beginning and so underestimated as CIN 1. These results reveal that the negative predictive value of p16 to predict the outcome of the cases of CIN 1 is as high as 96%, which strongly suggest an important role of p16 in the assessment of this type of lesion.  相似文献   
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