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21.
OBJECTIVES: Leakage around retrograde fillings is an important cause of endodontic surgery. This in vitro study sought to compare the following: (1) methylene blue dye leakage linked to retrofillings in human and sheep teeth with the degree of dye penetration when intermediate restorative materials and Chemfil were used as retrofillings, (2) the apical microleakage in filled with that in unfilled root canals, and (3) 2 storage techniques, incubator-based and subcutaneous implantation in rats. STUDY DESIGN: Tested were 198 human and 196 sheep teeth that were retrofilled with intermediate restorative material or Chemfil, then stored in an incubator or subcutaneously in rats for 10, 20, and 30 days before immersion in methylene blue dye for 24 hours. Linear dye penetration was evaluated, and the results were statistically analyzed by means of analysis of variance. RESULTS: Leakage between sheep and human teeth was significantly different (P <.05). Chemfil had significantly less leakage than intermediate restorative material after storage in rat (P <.05) for up to 20 days, but not after 30 days. No differences were found between leakage of unfilled and filled human root canal teeth. CONCLUSIONS: The sheep incisor is a poor experimental model of the human tooth, and both aging procedures demonstrate extensive leakage of retrofilling materials after long-term storage.  相似文献   
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BACKGROUND: Asking psychiatric in-patients about their drug consumption is unlikely to yield reliable results, particularly where alcohol and illicit drug use is involved. The main aim of this study was to compare spontaneous self-reports of drug use in hospitalized psychiatric patients to biological measures of same. A secondary aim was to determine which personal factors were associated with the use of tobacco, alcohol, and illicit drugs as indicated by these biological measures. METHODS: The consumption of substances was investigated using biological measures (urine cotinine, cannabis, opiates, cocaine, amphetamines and barbiturates; blood carbohydrate-deficient transferrin [CDT] and gamma-glutamyl transferase [GGT]) in 486 consecutively admitted psychiatric patients, one day following their hospitalization. Patients' self-reports of alcohol, tobacco and illicit drugs consumption were recorded. Socio-professional and familial data were also recorded. RESULTS: The results show a low correlation between biological measures and self-reported consumption of alcohol and illicit drugs. Fifty-two percent of the patients under-reported their consumption of illicit drugs (kappa=.47). Patients with schizophrenia and personality disorders were more likely to disclose their illicit drug consumption relative to patients suffering from mood disorders and alcohol dependence. Fifty-six percent of patients underreported alcohol use, as evaluated by CDT (kappa=.2), and 37% underreported when using the CDT+GGT measure as an indicator. Smoking appeared to be reported adequately. In the study we observed a strong negative correlation between cannabis use and age, a strong correlation between tobacco and cannabis use, and correlations between tobacco, cannabis and alcohol consumption. CONCLUSION: This study is the first to compare self-reports and biological measures of alcohol, tobacco and illicit drug uses in a large sample of inpatients suffering from various categories of psychiatric illnesses, allowing for cross-diagnosis comparisons.  相似文献   
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In Switzerland the Federal Office of Public Health has developeda comprehensive set of AIDS care and prevention policies andactivities in recent years. For their actual implementation,the main responsibility lies with the health departments ofthe 26 Cantons. This paper originates from one of the largeCantons, Vaud. Major efforts have been made from the Federallevel to transmit relevant AIDS-related information to the generalpublic. Much remains to be done to assist people, especiallyhigh risk groups, to translate the vital prevention messagesinto behaviour changes. For youth in general, new attitudestowards sexual relations are called for, different from thoseof young people 10 or 15 years ago. In Vaud, a number of entrypoints are used to pass on this education: physicians and nursesinvolved in school health, teachers and, among the latter, twogroups with specific in-service training and part-time functions—mediators(who make themselves available to children in various risk situations)and health animators (promoting the inclusion of health educationtopics in the teaching). There is a special health programmefor 16–19 year olds. Also a substantial tradition of sexualeducation sessions in the school system offers valuable opportunitiesfor AIDS education. Further, innovative strategies are developedto reach and work with the male homosexuals and, to the extentpossible, intravenous drug addicts. In conclusion it is emphasizedthat, in many ways, AIDS education issues demand courage fromhealth and public leaders.  相似文献   
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Background: Pain after amputation is common but difficult to treat, and few controlled treatment studies exist.

Methods: In the current study, 94 treatment-naive posttraumatic limb amputees with phantom pain (intensity: mean visual analog scale score [0-100], 40 [95% confidence interval, 38-41]) were randomly assigned to receive individually titrated doses of tramadol, placebo (double-blind comparison), or amitriptyline (open comparison) for 1 month. Nonresponders were crossed over to the alternative active treatment.

Results: After 1 month, phantom pain intensity was 1 (0-2) in the 48 tramadol responders (mean dose, 448 mg [95% confidence interval, 391-505 mg]), 0 (0-0) in the 40 amitriptyline responders (55 [50-59] mg), and 0 (0-0) in the 2 placebo responders, with similar effects on stump pain. Cytochrome P-450 2D6 slow metabolizers derived greater analgesia from tramadol and less from amitriptyline compared with fast metabolizers in the first treatment week (P < 0.01). Electrical pain thresholds increased and pain during suprathreshold stimulation decreased markedly on the stump and, to a lesser extent, on the contralateral limb after 1 month of treatment with amitriptyline or tramadol. Adverse effects were minor in all groups, but more common with tramadol.  相似文献   

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BACKGROUND: In 1992 France set up a national cystic fibrosis observatory (Observatoire national de la mucoviscidose, ONM) to monitor the state of health of patients on an annual basis. Using the ONM data, this study estimates the main indicators for life expectancy and assesses the total number of cystic fibrosis patients. METHODS: The data for the years 1994 to 2003 are divided into 3-year periods. Life tables are drawn up for these periods, from which mean and median lengths of life are determined. Using the most recent life table, the number of births in 2003 and the incidence of the disease, the total population of patients can be estimated, assuming a stationary population. RESULTS: In 2001-2003, life expectancy at birth of patients registered with the ONM was 39.1 years and median length of life was 36.4 years. These results, substantially better than those of 1994-1996, are linked to improved conditions of patient inclusion in the ONM database, to improvements in their healthcare, but also to the limitations of the life tables. Based on the 2003 data, the total theoretical number of patients is 6490, and coverage by the ONM database is thus 63.2%. CONCLUSIONS: These provisional results demonstrate the need to convert the ONM observatory into a registry providing exhaustive coverage of all patients.  相似文献   
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OBJECTIVE: The efficacy of a low-protein diet in the secondary prevention of diabetic nephropathy is not established in patients with type 1 or type 2 diabetes mellitus. To determine whether a low-protein diet slows the decrease in glomerular filtration rate (GFR) and decreases the albumin excretion rate (AER) in diabetic patients with incipient and overt nephropathy, we performed a 2-year prospective, randomized controlled trial comparing the effects of a low-protein diet (0.8 g/kg/day) with a usual-protein diet. SETTING AND PATIENTS: The study was conducted in a University hospital and included 63 type 1 and type 2 diabetic patients with either incipient or overt nephropathy and mild renal failure (prestudy GFR, 80 +/- 20 mL/min). The primary outcome measures were decreased in GFR and 24-hour AER. RESULTS: In the low-protein-diet group, patients were younger (52 +/- 12 versus 63 +/- 9 years old) and more often were type 2 diabetic. During the follow-up period, according to dietary records the low-protein-diet group consumed 16% +/- 3% of total caloric intakes as compared with 19% +/- 4% in the usual-protein-diet group (P < .02), but 24-hour urinary urea excretions did not differ between the two groups. The 2-year GFR decrease was 7 +/- 11 mL/min in the low-protein-diet group and 5 +/- 15 mL/min in the usual-protein-diet group (P = not significant). AER did not increase significantly in the two diet groups during the follow-up period. Blood pressure and glycemic control were similar in the two groups all along the study. The decrease in GFR and AER were also similar in 6 compliant patients according to dietary records and to 24-hour urinary urea excretions from the low-protein-diet group and in 12 patients from the usual-protein-diet group. CONCLUSIONS: A 2-year low-protein diet did not alter the course of GFR or of AER in diabetic patients with incipient or overt nephropathy receiving renin-angiotensin blockers with strict blood pressure control.  相似文献   
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