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81.
B Benyahia R Liblau H Merle-Béral JM Tourani J Dalmau JY Delattre 《Canadian Metallurgical Quarterly》1999,45(2):162-167
The authors investigated the association of caffeinated coffee, decaffeinated coffee, and tea with myocardial infarction in a study of 340 cases and age-, sex-, and community-matched controls. The odds ratio for drinking > or = 4 cups/day of caffeinated coffee versus drinking < or = 1 cup/week was 0.84 (95% confidence interval (CI) 0.49-1.42) after adjustment for coronary risk factors (1 cup = 237 ml). The odds ratio for drinking > 1 cup/day of decaffeinated coffee versus nondrinkers was 1.25 (95% CI 0.76-2.04). For tea, the odds ratio for drinking > or = 1 cup/day versus nondrinkers was 0.56 (95% CI 0.35-0.90). In these data, only tea was associated with a lower risk of myocardial infarction. 相似文献
82.
Aguilar A.D. Forzani E.S. Nagahara L.A. Amlani I. Tsui R. Tao N.J. 《IEEE sensors journal》2008,8(3):269-273
We present an ammonia sensor for human breath analysis based on electrically conducting polymer nanojunctions. Each nanojunction is formed by bridging a pair of gold nanoelectrodes on a silicon chip separated by a small gap (<60 nm) with electrodeposited polyaniline. The signal transduction mechanism of the sensor is the change in the nanojunction conductance as a result of polymer dedoping by ammonia. The sensor response to human breath is validated by comparison with a reference method for detection of ammonium ion combined with an optimized breath ammonia trapping system. The nanojunction sensor is capable of in situ detection of parts per billion (ppb) levels of ammonia in human breath. 相似文献
83.
OBJECTIVE: To determine the frequency of characteristics associated with unprotected heterosexual intercourse in HIV infected adults in an urban area. DESIGN: Retrospective comparison of sexual risk transmission behaviour between HIV infected men and women from a drug treatment site and between women from the drug site and HIV infected women from an urban medical centre. METHODS: HIV infected women and men were asked questions on sexual behaviour for a 1 year period before enrollment. The outcome variable was heterosexual risk behaviour (HRB) defined as having vaginal sex at least once in the previous year and not always using condoms. RESULTS: 73% of the drug clinic females, 72% of the drug clinic males, and 42% of the medical centre female engaged in HRB. Using logistic regression analysis, women and men in drug treatment engaged in similar rates of HRB; however, women in drug treatment were four times (95% CI = 2.0-8.3) more likely to engage in HRB risk behaviour than women from the medical centre. CONCLUSION: The data suggest that a surprisingly large portion of HIV infected patients under treatment engaged in HRB, especially former drug users. Without specifically targeted interventions, the heterosexual spread of HIV in urban areas will continue to be a serious problem. 相似文献
84.
Haemolytic anaemia as a complication of acute hepatitis has been reported in up to 23% of patients. However, the incidence may rise up to 70-87% in patients who have glucose-6-phosphate dehydrogenase (G6PD) deficiency. Massive intravascular haemolysis with renal failure, hepatic encephalopathy and even death have been reported. In our retrospective study of patients with acute viral hepatitis, the overall incidence of acute haemolysis was 4% (17/434). Only 53% (9/17) of them had G6PD deficiency. Patients with acute haemolysis had a significantly higher peak bilirubin level and required more prolonged hospitalization. Since hepatitis A virus vaccination, unlike hepatitis B virus vaccination, is not yet recommended for routine immunization, we suggest subjects who are G6PD-deficient should be vaccinated against hepatitis A. In endemic areas of hepatitis A virus infection, universal immunization remains the definitive answer. 相似文献
85.
JP Gibbs G Murray L Risler JY Chien R Dev JT Slattery 《Canadian Metallurgical Quarterly》1997,57(24):5509-5516
Busulfan, a bifunctional alkylating agent, is a mainstay of myeloablative preparative regimens before hematopoietic stem cell transplantation. The apparent oral clearance of busulfan expressed relative to body surface area is 2-3-fold higher in children 1-4 years old than it is in adults. The first step in busulfan elimination is the formation of a tetrahydrothiophenium ion (THT+) in a glutathione S-transferase-catalyzed reaction. We present computer simulations that demonstrate that the ratio of the AUC of THT+ to that of busulfan over 6 h [(AUC(THT+)/AUC(BU))(0-->6)] is highly correlated (r2 = 0.805) with the determinants of THT+ formation and is virtually independent of the determinants of its elimination (r2 = 0.0201). We compared (AUC(THT+)/AUC(BU))(0-->6) determined in 14 children (0.5-4 years) to that of 11 adults (12-54 years) and found a 1.5-fold elevation in the area ratio (P = 0.0098) and a similarly significant increase in busulfan apparent oral clearance expressed relative to body surface area (P = 0.042). The only common explanation for the elevated busulfan apparent oral clearance and (AUC(THT+)/AUC(BU))(0-->6) is an enhanced ability of children to metabolize busulfan through glutathione conjugation. 相似文献
86.
87.
Studies the problem formulated by Ge and Feng (Int. J. Contr., vol.47, p.581-600 (1988)), which is to design a set of observers which can detect and locate unknown system failure to any first-order state component. The present paper proposes a much simpler solution to this problem with less restrictions. Based on this solution, an extended study of the required number of observers and their orders is also provided 相似文献
88.
89.
A dispersion- and polarisation-insensitive all-optical method for transmitting and extracting a subcarrier multiplexed (SCM) signal using a fibre Bragg grating filter without a conventional SCM circuitry is demonstrated. Fibre transmission experiments conducted on standard singlemode fibres of varying lengths up to 80 km showed excellent sensitivity with no apparent fading effects 相似文献
90.