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101.
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Brandon DL. Marshall Evan Wood Jean A. Shoveller Jane A. Buxton Julio SG. Montaner Thomas Kerr 《Prevention science》2011,12(2):173-180
The purpose of this study was to determine the incidence and predictors of initiating methamphetamine injection among a cohort
of injection drug users (IDU). We conducted a longitudinal analysis of IDU participating in a prospective study between June
2001 and May 2008 in Vancouver, Canada. IDU who had never reported injecting methamphetamine at the study’s commencement were
eligible. We used Cox proportional hazards models to identify the predictors of initiating methamphetamine injection. The
outcome was time to first report of methamphetamine injection. Time-updated independent variables of interest included sociodemographic
characteristics, drug use patterns, and social, economic and environmental factors. Of 1317 eligible individuals, the median
age was 39.9 and 522 (39.6%) were female. At the study’s conclusion, 200 (15.2%) participants had initiated injecting methamphetamine
(incidence density: 4.3 per 100 person-years). In multivariate analysis, age (adjusted hazard ratio [aHR]: 0.96 per year older,
95%CI: 0.95–0.98), female sex (aHR: 0.58, 95%CI: 0.41–0.82), sexual abuse (aHR: 1.63, 95%CI: 1.18–2.23), using drugs in Vancouver’s
drug scene epicentre (aHR: 2.15 95%CI: 1.49–3.10), homelessness (aHR: 1.43, 95%CI: 1.01–2.04), non-injection crack cocaine
use (aHR: 2.06, 95%CI: 1.36–3.14), and non-injection methamphetamine use (aHR: 3.69, 95%CI: 2.03–6.70) were associated with
initiating methamphetamine injection. We observed a high incidence of methamphetamine initiation, particularly among young
IDU, stimulant users, homeless individuals, and those involved in the city’s open drug scene. These data should be useful
for the development of a broad set of interventions aimed at reducing initiation into methamphetamine injection among IDU. 相似文献
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Franz X. Roithinger Martin R. Karch Paul R. Steiner Arne SippensGroenewegen Michael D. Lesh 《Journal of interventional cardiac electrophysiology》1999,3(4):311-319
The local dispersion of conduction and refractoriness has been considered essential for induction of atrial arrhythmias. This study sought to determine whether a difference of refractoriness and vulnerability for induction of atrial fibrillation between trabeculated and smooth as well as high and low right atrium may contribute to initiation of atrial fibrillation in dogs.In 14 healthy mongrel dogs weighing 22.4 ± 1 kg, closed-chest endocardial programmed stimulation was performed from four distinct right atrial sites. Atrial refractory periods and vulnerability for induction of atrial fibrillation or premature atrial complexes were determined during a basic cycle length of 400 and 300 ms and an increasing pacing current strength.For a pacing cycle length of 300ms, atrial refractory periods were longer on the smooth, as compared to the trabeculated right atrium (102 ± 25 vs. 97 ± 17ms, p < 0.05), whereas for a pacing cycle length of 400ms, there was no significant difference. The duration of the vulnerability zone for induction of atrial fibrillation was longer on the smooth right atrium, for a cycle length of both 400 ms (40 ± 30 vs. 31 ± 22 ms; p < 0.05) and 300 ms (33 ± 25 vs. 23 ± 21 ms; p < 0.01). When comparing high and low right atrium, refractory periods were longer on the the low right atrium, for a cycle length of both 400 ms (111 ± 23 vs. 94 ± 24ms; p < 0.01) and 300 ms (104 ± 20 vs. 96 ± 23ms; p < 0.01). For a pacing cycle length of 300 ms, the duration of the atrial fibrillation vulnerability zone was longer for the high, as compared to the low right atrium (34 ± 22 vs. 22 ± 22, p < 0.01). Seven dogs with easily inducible episodes of atrial fibrillation demonstrated significantly shorter refractory periods as compared to 7 non-vulnerable dogs, regardless of pacing site and current strength.In conclusion, significant differences in refractoriness and vulnerability for induction of atrial fibrillation can be observed in the area of the crista terminalis in healthy dogs. Thus, local anatomic factors may play a role in the initiation of atrial fibrillation. 相似文献
107.
SG Münster 《MedR Medizinrecht》1999,17(8):384-386
Ohne Zusammenfassung 相似文献
108.
SG Frankfurt a. M. 《MedR Medizinrecht》1999,17(12):577-578
Ohne Zusammenfassung 相似文献
109.
SG Münster 《MedR Medizinrecht》1999,17(12):581-584
Ohne Zusammenfassung 相似文献
110.
SG Hamburg 《MedR Medizinrecht》1999,17(12):578-581
Ohne Zusammenfassung 相似文献