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81.
RJ Gilbertson E Harris SK Pandey P Kelly W Myers 《Archives of disease in childhood》1996,75(3):194-198
Paracetamol is the commonest agent employed in self poisoning, however it is not clear whether adolescents possess insight into the serious complications associated with its misuse. Using a one page questionnaire, the availability, usage, and knowledge of toxicity of paracetamol among 1147 American and British adolescents was assessed. Although 90% of all students recognised that paracetamol could kill, the great majority of students overestimated the lethal dose. In addition, while knowledge regarding side effects of paracetamol was poor the drug was widely available to, and used by, the study population. It is proposed that gross overestimation of the number of tablets required to kill, poor understanding of paracetamol side effects, and wide availability of the drug contribute to its frequent use in adolescent suicidal behaviour. The inclusion of some over-the-counter medications in school drug education programs in addition to tighter control of the availability of paracetamol may help reduce the problem of adolescent self poisoning. 相似文献
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84.
Uterine leiomyomas in the infertile patient: preoperative localization with MR imaging versus US and hysterosalpingography 总被引:2,自引:0,他引:2
Eleven women with a history of infertility and uterine leiomyomas underwent magnetic resonance (MR) imaging of the pelvis prior to myomectomy. Nine also underwent preoperative pelvic ultrasonography (US), and ten underwent hysterosalpingography. All studies were interpreted prospectively by independent observers. With each imaging modality, the location (one of 11 anatomic segments), size, and appearance of detected uterine leiomyomas were determined and compared with surgical and histologic findings. Among the nine patients who underwent both MR and US, the sensitivity (85%) and accuracy (94%) of MR imaging for abnormal segments was significantly better than that of US (sensitivity = 69%, P = .015; accuracy = 87%, P = .043). For the ten patients who underwent both MR and hysterosalpingography, the sensitivity (91%) and accuracy (96%) of MR imaging was better than that of hysterosalpingography (sensitivity = 18%, P = .0005; accuracy = 72%, P = .0005). The specificities of the three modalities did not significantly differ (100%, 97%, and 98% for MR, US, and hysterosalpingography, respectively). These data suggest that MR imaging is superior to US or hysterosalpingography for preoperatively locating uterine leiomyomas. 相似文献
85.
MAGNOLOL REDUCES INFARCT SIZE AND SUPPRESSES VENTRICULAR ARRHYTHMIA IN RATS SUBJECTED TO CORONARY LIGATION 总被引:7,自引:0,他引:7
1. Magnolol is an active component of Magnolia officinalis. It is 1000-times more potent than α-tocopherol in inhibiting lipid peroxidation in rat heart mitochondira. In the present study, the in vivo antiarrhythmic and anti-ischaemic effects of magnolol in coronary ligated rats were investigated. 2. Male Sprague-Dawley rats were anaesthetized with urethane. Magnolol, at dosages of 10?7, 10?8 and 10?9 g/kg, was adminstered intravenously 15 min before ligation of the coronary artery. 3. The incidence and duration of ventricular tachycardia and ventricular fibrillation during 30 min coronary ligation were significantly reduced by magnolol. Ventricular arrhythmias during 10 min reperfusion after the relief of coronary ligation were also reduced. 4. In rats subjected to 4h coronary ligation, 10?7 and 10?8 g/kg magnolol significantly reduced infarct size. 5. We conclude that magnolol may protect the myocardium against ischaemic injury and suppress ventricular arrhythmia during ischaemia and reperfusion. 相似文献
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This study described the various components of access to care for resectable colorectal cancer, and correlated the timeliness of these components with patient satisfaction. With a prospective/retrospective cohort design, all patients undergoing surgical resection for primary colorectal cancer from 2/1/01 to 15/12/01, were identified during their admission for surgery. A comprehensive, standardized method of ascertaining specific time intervals, which included a patient interview, was used. A patient satisfaction questionnaire was developed, tested, and used in consenting patients. Over the study period, 118 patients underwent colorectal cancer resection. Of these, 110 (93%) consented to participate and 101 (86%) completed the satisfaction questionnaire, including test-retest. The median time intervals (interquartile range) for the various components of access to care were as follows: symptoms to first physician visit, 32 days (10-75); first physician visit to diagnosis, 88 days (44-218); diagnosis to surgery, 19 days (10-44); surgery to chemotherapy (where applicable), 54 days (47-72). On multivariate analysis, tumor location in the rectum was associated with longer prediagnosis intervals, whereas increasing tumor stage was associated with shorter intervals from diagnosis to surgery. Variation in the time interval from diagnosis to surgery was associated with patient satisfaction (r = 0.49; P < 0.0001). Substantially less correlation was identified between patient satisfaction and the time from first physician visit to diagnosis (r = 0.25, P = 0.04). No significant correlation was identified between patient satisfaction scores and the time interval from symptoms to first physician visit (r = 0.11; P = 0.7). Despite concerns regarding surgical waitlists, the longest time intervals experienced by colorectal cancer patients precede diagnosis. However, variations in the relatively short time period from diagnosis to surgery appeared to have the most impact on patient satisfaction. Interventions which improve the timeliness of specific components of access to care may not necessarily result in improved patient satisfaction. 相似文献
88.
Background
In view of increase in incidence of exptrapulmonary tuberculosis after the epidemic of human immunodeficiency virus infection, the clinical profile of extrapulmonary tuberculosis in patients with HIV infection was studied.Method
The study population comprised patients of HIV infection with extrapulmonary tuberculosis. Work up included history, clinical examination, sputum for acid fast bacilli, chext X-ray, ultrasonography (USG) abdomen, fine needle aspiration cytology(FNAC), transbronchial needle aspiration (TBNA) and computed tomography of chest.Results
There were 50 cases, all males with mean age of 35 years. 24(48%) were without pulmonary tuberculosis and 26(52%) had pulmonary tuberculosis. 41(82%) had disseminated disease and 9(18%) involve one site. Fever and weight loss were the most frequent symptoms (79% and 58% respectively) in cases without pulmonary tuberculosis. The most frequent extrapulmonary site was lymph node in 46(92%), followed by spleen in 13(26%), pleura 9(18%), miliary 7(14%) and hepatic 1(2%). The diagnosis was confirmed by invasive methods in 30 out of 50(60%) cases [FNAC in 23(88%), TBNA in 2(25%) and pleural biopsy in 5(55%)].Conclusion
In HIV infected patients, the most common extrapulmonary site is lymph mode followed by spleen.Key Words: Extrapulmonary TB, HIV Infection 相似文献89.
Beattie KA Boulos P Pui M O'Neill J Inglis D Webber CE Adachi JD 《Osteoarthritis and cartilage / OARS, Osteoarthritis Research Society》2005,13(3):181-186
OBJECTIVE: To estimate the prevalence of bone and soft tissue abnormalities in asymptomatic knees using peripheral magnetic resonance imaging (pMRI) and to examine the relationship between these abnormalities and Kellgren-Lawrence (K-L) graded X-rays. METHOD: Volunteers (20-68 years) with no history of knee pain, injury or bone or joint disease were recruited. Individuals underwent a single MRI scan and radiograph of their non-dominant knee. pMR images were acquired in sagittal plane using a 3-D gradient-echo protocol. Two radiologists graded the presence and severity of cartilage degeneration, osteophytosis, meniscal and ligamentous abnormalities, bone marrow edema and subchondral cysts. X-rays were acquired using a fixed-flexion technique and graded using the K-L scale. RESULTS: Forty-four individuals, mean age (SD) 41.1 (14.2) years, participated. K-L grading of X-rays revealed 29 individuals were grade 0, 12 were grade 1 and 3 were grade 2. Five individuals showed evidence of cartilage lesions, the femoral trochlea, medial femur and patella being those regions most commonly affected. Twelve individuals (27.3%) showed evidence of osteophytosis, nine of whom did not show evidence on X-ray. Forty-three individuals showed evidence of at least one meniscal abnormality while 27 individuals (61.4%) had abnormalities in at least three of the four regions of the knee. CONCLUSION: Our results suggest that osteophytes may be more prevalent in this population than radiographic data suggests due to the limitations of two-dimensional imaging. Meniscal degeneration or tears, a risk factor for knee osteoarthritis, are highly prevalent in asymptomatic individuals with the medial anterior and posterior horns being the most commonly affected regions. 相似文献
90.
Wakefield M Cameron M Inglis G Letcher T Durkin S 《Journal of occupational and environmental medicine / American College of Occupational and Environmental Medicine》2005,47(7):698-703
OBJECTIVE: To examine the association between smoke-free policies, exposure to secondhand smoke (SHS) at work, and self-reported respiratory and sensory symptoms of workers. METHOD: Ninety-one nonsmoking workers recruited from three workplaces with varying smoking policies completed a telephone-administered questionnaire and provided saliva samples (before and after usual work shift) for cotinine analysis. RESULTS: Mean before-after shift saliva cotinine per hour worked was significantly higher among club (0.42 ng/mL/hr worked) than casino workers (0.18 ng/mL/hr worked) (P < 0.001), club than office workers (0.03 ng/mL/hr worked) (P < 0.001), and casino than office workers (P < 0.001). Casino and club workers reported similar levels of respiratory morbidity and were more likely to have sore eyes (odds ratio [OR] = 5.5, P < 0.01) and a sore throat (OR = 4.3, P < 0.05) compared with office employees. CONCLUSION: Air-conditioning interventions reduce, but fail to eliminate, exposure of hospitality workers to SHS. Such exposure is associated with measurable increases in the risk of respiratory symptoms. 相似文献