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41.
WickramasingheR 《环境与健康杂志》2002,19(5):F003-F003
公元1839年茶叶由印度阿萨姆带入锡兰 (即现在的斯里兰卡 ) ,并栽入皇家公园内。1867年是吉米·泰勒 (JamesTaylor)最早在锡兰因咖啡种植中遭受锈叶病的损害 ,而开始茶叶的商业性栽培。在泰勒开始栽培茶叶时只有8hm2面积 ,之后在斯里兰卡茶叶栽培和加工制作 ,不管是数量和质量都有很大进步 ,至1965年斯里兰卡已成为世界主要茶叶出口国 ,由此可见 ,茶叶加工工业对斯里兰卡的经济和自然景观都有巨大的作用。茶树是一种全年皆可生长的作物 ,它比种植咖啡需要投入更多劳动力 ,同时考虑要形成一个利于市场销售的商品 … 相似文献
42.
Role of superoxide anion radicals in ethanol metabolism by blood monocyte-derived human macrophages 总被引:1,自引:0,他引:1 下载免费PDF全文
S N Wickramasinghe 《The Journal of experimental medicine》1989,169(3):755-763
The effects of a number of additives on the rate of conversion of ethanol (1 mg/ml; 21.7 mM) to acetate by monolayers of blood monocyte-derived human macrophages were investigated. The additives studied were superoxide dismutase (SOD; 1,500 U/ml), catalase (1,500 U/ml), tetrahydrofurane (20 mM), and PMA (20 nM), either singly or in various combinations. SOD, catalase, SOD plus catalase, tetrahydrofurane, and tetrahydrofurane plus SOD inhibited ethanol oxidation by 49.2, 12.1, 52.9, 60.4, and 66.8%, respectively. PMA caused a 4.0-8.3-fold increase in the rate of ethanol metabolism and this increase was completely suppressed in the presence of SOD. The data indicate that a substantial proportion of the ethanol metabolism by both unstimulated and PMA-stimulated blood monocyte-derived macrophages was dependent on the generation of superoxide anion radicals. 相似文献
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44.
Serologic test for syphilis as a surrogate marker for human immunodeficiency virus infection among United States blood donors 总被引:2,自引:0,他引:2
GA Herrera ; EM Lackritz ; RS Janssen ; VP Raimondi ; RY Dodd ; J Aberle-Grasse ; LR Petersen 《Transfusion》1997,37(8):836-840
BACKGROUND: This study evaluated the usefulness of the serologic test for syphilis (STS) in preventing the transmission of human immunodeficiency virus (HIV), hepatitis B and C viruses, and human T- lymphotropic virus via the transfusion of seronegative, infectious window-period blood. STUDY DESIGN AND METHODS: Demographic and laboratory information on blood donations made between January 1992 and June 1994 in 18 American Red Cross regions was analyzed. It was assumed that the same proportion of HIV-positive and HIV-infectious window- period donations reacted on STS and were negative on other screening tests (hepatitis B and C viruses and human T-lymphotropic virus). This proportion multiplied by the estimated number of HIV-infectious window- period donations is the number of post-screening HIV-infectious donations removed by STS. RESULTS: Of 4,468,570 donations, 12,145 (0.27%) were STS positive and 377 (0.008%) were HIV positive. Among donations that were negative on other screening tests, STS-reactive donations were 12 times more likely to be HIV positive (odds ratio = 11.9; 95% CI = 5,26). However, of an estimated 13 infectious window- period donations, 0.2 would have been removed because of a reactive STS, at a cost of over $16 million. CONCLUSION: STS is a poor marker and a costly strategy for preventing post-screening HIV infections and other blood-borne diseases. 相似文献
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46.
Background: Adenoidectomy is a commonly performed ENT surgery. It is conventionally performed using the curettage method. This present article aims to evaluate endoscopic powered adenoidectomy as an alternative. 相似文献
47.
Background
Adenoidectomy is a commonly performed ENT surgery. It is conventionally performed using the curettage method. This present article aims to evaluate endoscopic powered adenoidectomy as an alternative.Methods
Sixty consecutive cases requiring adenoidectomy were randomized into two groups of thirty each. Group A underwent conventional adenoidectomy using the curettage method and Group B underwent endoscopic assisted micro-debrider adenoidectomy. The parameters studied were intra-operative time, intra-operative bleeding and completeness of resection, collateral damage, post operative pain and recovery time.Result
Sixty cases of adenoidectomy were done using conventional surgery and powered endoscopic adenoidectomy in the study period from Aug 04 to Dec 05. The time taken in Group A (conventional surgery) varied from 22–39 minutes (95% Confidence Interval (CI) −27.7 – 30.9)and in Group B (powered endoscopic surgery) from 27–55 minutes(95% CI 36.6 – 41.9) (p<0.05). The average blood loss in Group A was 21 ml (range 10–50) as compared to 31.67 ml (range 10-60) in Group B (p<0.05). The resection was invariably complete in Group B whereas seven(23%) cases had more than 50% residual adenoid tissue in Group A. Three cases in group A had collateral damage whereas in Group B, there were no added injuries. Post operative pain was studied only in cases undergoing adenoidectomy alone. Group A (n=8) demonstrated a pain score of 1.64–2.63–3.63 (95% CI) whereas Group B (n=11) demonstrated a pain score of 1.19–2.13–3.06 (95% CI). This difference was not statistically significant. In group A, the mean recovery period was 3.5 days and 2.93 days in Group B(p<0.05).Conclusion
Endoscopic powered adenoidectomy was found to be a safe and effective tool for adenoidectomy. The study parameters where endoscopic powered adenoidectomy fared better were completeness of resection, accurate resection under vision, lesser collateral damage and faster recovery time. On the other hand, conventional adenoidectomy scored in matter of lesser operative time and intra-operative bleeding.Key Words: Adenoidectomy, Powered adenoidectomy, Endoscopic adenoidectomy 相似文献48.
Fernando SD Wickramasinghe VP Kapilananda GM Devasurendra RL Amarasooriya JD Dayaratne HG 《The Southeast Asian journal of tropical medicine and public health》2007,38(6):983-990
This cross-sectional study, carried out over a period of 11 months, investigated the relationship between Toxocara seropositivity, socio-demographic and environmental variables in a pediatric population. Risk factors for Toxocara infection were assessed by direct interview of parent or guardian using a structured pre-tested questionnaire. Eosinophilia and presence of helminth eggs or protozoan cysts in a fecal smear were recorded. Diagnosis of Toxocara seropositivity in children was based on IgG Toxocara Microwell Serum Elisa Kits. The ELISA test was regarded as positive if the optical density was 0.3 units or above. Unadjusted and adjusted odds ratios were calculated to determine risk factors for disease. The proportion of children who were positive for Toxocara antibodies in the study population was 20%. Children being exposed to a puppy of less than 3 months at home, visiting a playground frequently, living in a poorly constructed house and dogs having access to playgrounds were significant risk factors on univariate analysis. Of these four variables, only the first three variables (OR 19, OR 4 and OR 3, respectively) remained significant risk factors on the multivariate model. Presence of eosinophilia in seropositive children was significantly higher than the seronegative group (77% vs 40%; p < 0.001). This study indicates that dogs contribute significantly to children being seropositive for toxocariasis in Sri Lanka. Implementation of public health programs specifically focused on anti-parasitic treatment of dogs is recommended. 相似文献
49.
Cases of congenital dyserythropoietic anemia (CDA) that do not conform to any of the three classical types often present diagnostic difficulties and are at risk of developing secondary hemochromatosis. Here, we report a case of a six year old boy with transfusion dependency and gross abnormalities of the erythroblasts. 相似文献