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31.
Mark W Tyndall Evan Wood Ruth Zhang Calvin Lai Julio SG Montaner Thomas Kerr 《Harm reduction journal》2006,3(1):36-5
North America's first government sanctioned medically supervised injection facility (SIF) was opened during September 2003
in Vancouver, Canada. This was in response to a large open public drug scene, high rates of HIV and hepatitis C transmission,
fatal drug overdoses, and poor health outcomes among the city's injection drug users. Between December 2003 and April 2005,
a representative sample of 1,035 SIF participants were enrolled in a prospective cohort that required completing an interviewer-administered
questionnaire and providing a blood sample for HIV testing. HIV infection was detected in 170/1007 (17%) participants and
was associated with Aboriginal ethnicity (adjusted Odds Ratio [aOR], 2.70, 95% Confidence Interval [95% CI], 1.84–3.97), a
history of borrowing used needles/syringes (aOR, 2.0, 95% CI, 1.37–2.93), previous incarceration (aOR, 1.87, 95% CI, 1.11–3.14),
and daily injection cocaine use (aOR, 1.42, 95% CI, 1.00–2.03). The SIF has attracted a large number of marginalized injection
drug users and presents an excellent opportunity to enhance HIV prevention through education, the provision of sterile injecting
equipment, and a supervised environment to self-inject. In addition, the SIF is an important point of contact for HIV positive
individuals who may not be participating in HIV care and treatment. 相似文献
32.
MR imaging of the breast 总被引:11,自引:0,他引:11
Orel SG 《Radiologic clinics of North America》2000,38(4):899-913
The results of clinical investigation suggest that MR imaging can provide clinically important information that cannot be obtained with conventional imaging methods, and that this modality will, in the future, be an invaluable adjunctive breast imaging tool just as breast ultrasound is today. MR imaging appears to be the most accurate method for the detection of implant failure, and although it is the most costly of the available implant imaging techniques, it may be the study of choice when there is a question of implant integrity that cannot be answered with conventional methods. MR imaging as a method to detect, diagnose, and stage breast cancer remains in the investigational stage. The specificity of MR imaging appears limited because of the overlap in the enhancement kinetics and morphologic appearance of benign and malignant lesions. In selected cases, the identification of certain morphologic features, such as internal septations or the absence of enhancement, may be used to classify a lesion as benign, offering an alternative to percutaneous or excisional biopsy. MR imaging appears to be very sensitive for the visualization of both invasive carcinoma and DCIS. Perhaps most important, MR imaging can detect invasive and noninvasive breast carcinoma that is both mammographically and clinically occult, offering the potential for more accurate breast cancer staging and optimized treatment planning. MR imaging is emerging as perhaps the most promising imaging modality for breast cancer detection to date. Published results, however, are from studies with relatively small numbers of patients. The results of these studies should be validated in a large-scale clinical trial before MR imaging is implemented clinically, outside of research settings. This type of clinical investigation is needed to define the technical requirements for optimal imaging, to define interpretation criteria, to develop accurate MR imaging guided localization and biopsy systems, to define the clinical indications for which MR imaging should be used as an adjunct to conventional imaging methods, and to address the issue of cost-effectiveness. One such trial, an international, multi-institutional study funded by the National Cancer Institute, is presently underway. 相似文献
33.
Brandon DL Marshall Thomas Kerr Chris Livingstone Kathy Li Julio SG Montaner Evan Wood 《Harm reduction journal》2008,5(1):35
Aboriginal people experience a disproportionate burden of HIV infection among the adult population in Canada; however, less
is known regarding the prevalence and characteristics of HIV positivity among drug-using and street-involved Aboriginal youth.
We examined HIV seroprevalence and risk factors among a cohort of 529 street-involved youth in Vancouver, Canada. At baseline,
15 (2.8%) were HIV positive, of whom 7 (46.7%) were Aboriginal. Aboriginal ethnicity was a significant correlate of HIV infection
(odds ratio = 2.87, 95%CI: 1.02 – 8.09). Of the HIV positive participants, 2 (28.6%) Aboriginals and 6 (75.0%) non-Aboriginals
reported injection drug use; furthermore, hepatitis C co-infection was significantly less common among Aboriginal participants
(p = 0.041). These findings suggest that factors other than injection drug use may promote HIV transmission among street-involved
Aboriginal youth, and provide further evidence that culturally appropriate and evidence-based interventions for HIV prevention
among Aboriginal young people are urgently required. 相似文献
34.
Evidence for endogenous formation of tobacco-specific nitrosamines in rats treated with tobacco alkaloids and sodium nitrite 总被引:2,自引:0,他引:2
Carcinogenic tobacco-specific nitrosamines are present in tobacco products
and are believed to play a significant role in human cancers associated
with tobacco use. Additional amounts of tobacco-specific nitrosamines could
be formed endogenously. We tested this hypothesis by treating rats with
nicotine and sodium nitrite and analyzing their urine. Initially, we
treated groups of rats with (S)-nicotine (60 micromol/kg) and NaNO2 (180
micromol/kg), (S)-nicotine alone, NaNO2 alone or
4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK, 12 nmol/kg) by gavage
twice daily for 4 days. We collected urine and analyzed for two metabolites
of NNK; 4-(methylnitrosamino)-1-(3- pyridyl)-1-butanol and its glucuronide.
We did not detect these metabolites in the urine of rats treated with
nicotine alone or nicotine plus NaNO2, indicating that endogenous
conversion of nicotine to NNK did not occur. However, the urine did contain
N'- nitrosonornicotine (NNN), N'-nitrosoanabasine (NAB) and N'-
nitrosoanatabine (NAT). Analysis of the (S)-nicotine used in this
experiment demonstrated that it contained trace amounts of nornicotine,
anabasine and anatabine. In a second experiment, we used an identical
protocol to compare the endogenous nitrosation of this (S)-nicotine with
that of synthetic (R,S)-nicotine, which did not contain detectable amounts
of nornicotine, anabasine or anatabine. NNN (0.53 x 10(-3)% of nicotine
dose), NAB (0.68%) and NAT (2.1%) were detected in the urine of the rats
treated with the (S)-nicotine and NaNO2. NNN (0.47 x 10(- 3)% of dose), but
not NAB or NAT, was present in the urine of the rats treated with synthetic
(R,S)-nicotine and NaNO2. NNN probably formed via nitrosation of
metabolically formed nornicotine. These results demonstrate for the first
time that endogenous formation of tobacco- specific nitrosamines occurs in
rats treated with tobacco alkaloids and NaNO2. The potential significance
of the results with respect to nitrosamine formation in people who use
tobacco products or nicotine replacement therapy is discussed.
相似文献
35.
36.
37.
Most studies dealing with the arterial system impedance as resistance to blood ejection from the left ventricle are based on catheterization examinations of the aorta and the great arteries. The present work shows the possibility of using non-invasive approaches and describes one of them consisting in non-invasive determination of arterial impedance by measuring arterial pressure, cardiac output and the cardiac cycle phase structure. The results are compared with those of other studies. 相似文献
38.
SG Stuttgart 《MedR Medizinrecht》1998,16(11):530-531
Ohne Zusammenfassung 相似文献
39.
40.
An in vitro is described that attempts to detect patients with a potential for adverse systemic reactions to contrast material. This test involves measuring the rate of conversion of prekallikrein to kallikrein under certain standard conditions. In a preliminary retrospective study, the test could be used to identify such patients with a sensitivity of 88%, a specificity of 82%, and a predictive value of 79%. 相似文献