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71.
72.
Hélène Gagnon Gaston Godin Michel Alary Julie Bruneau Joanne Otis 《AIDS and behavior》2010,14(3):538-548
The aim of this study was to evaluate the efficacy of a theory-based intervention to increase the use of a new syringe for
each injection among injection drug users (IDUs). Users of two needle exchange programs (NEPs) were involved. At both sites,
participants were assigned at random to either the experimental or the control group. Once a week for four weeks, users reported
to the NEPs where they logged onto a computer and received an audiovisual message. A total of 260 IDUs were recruited. At
baseline, 52.3% of participants reported that they had not always used new syringes in the previous week. The results indicate
that it is possible for IDUs to adopt safer injection practices. One month after the intervention began, participants in the
experimental group were using fewer dirty syringes compared to the control group (RR: 0.47 CI95% 0.28–0.79; P = .004). This short-term effect was no longer present 3 months later. 相似文献
73.
Politzer RM Trible LQ Robinson TD Heard D Weaver DL Reig SM Gaston M 《The Journal of ambulatory care management》2000,23(3):70-85
The National Health Service Corps (NHSC) was created in 1970 to provide primary health care clinicians for the underserved. The article includes a review of the peer-reviewed and intragovernmental literature on the NHSC program from 1971 to 1998 and also presents a current profile of the program. Despite significant increases in NHSC field strength since 1991, the 2,439 clinicians meet only 12% of the need for primary health care providers in underserved areas. While the NHSC has successfully addressed clinician diversity and retention issues, community and site development remain barriers to increasing access. Most communities in need are not ready to recruit and support clinicians. The NHSC of the next millennium must work with the neediest communities to reach the appropriate stage of readiness. Only after completing the necessary "preplacement" activities can the NHSC assist in the recruitment and placement of clinicians to increase access. 相似文献
74.
Inhibition of orthotopic growth and metastasis of androgen-sensitive human prostate tumors in mice by bioactive soybean components 总被引:4,自引:0,他引:4
BACKGROUND: Systematic analysis of the influence of diet on the initiation and progression of prostate cancer is often difficult in human populations, for which dietary variables overlap a diversity of genetic backgrounds and social behaviors. Animal models that emulate human prostate cancer allow experimental analysis of the mechanisms of action of nutritional agents that show anti-prostate cancer activity. METHODS: We have used an orthotopic implant model to characterize the in vivo response of androgen-sensitive LNCaP prostate tumors to three well-characterized soy dietary supplements: isoflavone depleted soy protein, soy phytochemical concentrate (SPC), and genistin. RESULTS: In male SCID mice orthotopically implanted with the androgen-sensitive human prostate cell line LNCaP, dietary supplements of soy protein, genistin, and SPC reduced primary tumor weight by 42% (P = 0.07), 57% (P < 0.05) and 70% (P < 0.005), respectively. All three soy supplements significantly increased tumor apoptosis and decrease microvessel density, with no significant change in tumor proliferation. Each supplement produced a distinct serum androgen response, with genistin producing the greatest decrease in total serum testosterone and dihydrotestosterone (DHT) (P < 0.05) and the greatest increase in testosterone to DHT ratio (P < 0.05) and soy protein the greatest decrease in bioactive androgen (P < 0.05). Only SPC significantly inhibited metastases to lymph nodes and lungs, and only SPC produced a significant increase in tumor p53 expression. CONCLUSION: Taken together, these data suggest that the anti-prostate cancer activity of dietary soy protein, soy phytochemicals, and genistin use different molecular pathways. In addition, we have demonstrated that this animal model can be used in the design of dietary strategies for prostate cancer prevention and therapy. 相似文献
75.
Despite extensive research, it remains unclear why a small proportion of HLA- B27(+) individuals develop spondyloarthropathies (SpA). Because the function of HLA-B27, as a major histocompatibility complex (MHC) class I molecule, is peptide presentation to CD8(+) T cells, research has concentrated on the role of HLA-B27 as a restriction element for CD8(+) cytotoxic T lymphocytes in pathogenesis. However, findings in the B27-transgenic animal models, together with the identification of unusual processing and presentation features of HLA-B27, have raised alternative hypotheses for the pathogenic role of HLA-B27. One such hypothesis is that HLA-B27 can be recognized by CD4(+) T lymphocytes. Here we report the identification of such unusual cells, which break the conventional rules of MHC restriction, and propose a model for the role of such CD4(+) T cells in SpA. 相似文献
76.
Skin testing to evaluate oculo-respiratory syndrome (ORS) associated with influenza vaccination during the 2000-2001 season 总被引:1,自引:0,他引:1
Skowronski DM De Serres G Hebert J Stark D Warrington R Macnabb J Shadmani R Rochette L MacDonald D Patrick DM Duval B 《Vaccine》2002,20(21-22):2713-2719
A syndrome of red eyes and respiratory symptoms was noted following receipt of influenza vaccine in Canada during the 2000-2001 influenza season. We conducted intra-dermal skin testing to determine if oculo-respiratory syndrome (ORS) was related to failure of the splitting process during vaccine manufacturing, if it was associated with a particular viral strain and to identify individuals at risk for subsequent ORS reaction. Skin testing with minute quantities of vaccine antigen induced ORS symptoms at a higher rate amongst persons previously affected by this syndrome compared to previously unaffected persons. Skin test reaction size or quality could not identify persons at risk of ORS. Skin testing could not identify a specific strain or the stage in the manufacturing process during which the trigger may have been introduced. 相似文献
77.
Wishart GC Gaston M Poultsidis AA Purushotham AD 《European journal of cancer (Oxford, England : 1990)》2002,38(9):1201-1203
In a previous study, we demonstrated wide variability in the access to oestrogen receptor (ER) measurement, patient selection, choice of technique and the cut-off point for positivity. The aim of this study was to update information on the current use of ER and progesterone receptor (PR) measurement in the United Kingdom (UK). Questionnaires, asking about availability, use and technique of ER and PR measurement, were returned from 170 (74%) units in the UK. Where ER positivity was determined using the percentage of cells staining positive (33%), the absolute cut-off point for positivity varied widely from 5 to 80% of cells. Of the 170 responding units, 107 (63%) felt that PR measurement was important. This study confirms considerable variability in both the technique of ER measurement and the absolute cut-off point for positivity (5-80%). It is essential that a consensus be reached regarding the choice of technique, as well as the threshold for positivity. 相似文献
78.
Sympathetic preganglionic neurons (SPN) in rat spinal cord were activated by the reflex stimulation of bulbospinal sympathetic neuronal pathways after a nitroprusside-induced hypotension. Hypotension-sensitive SPN, identified by immunoreactivity (IR) to the product of the immediate early gene c-fos and to choline acetyltransferase, were localized in the intermediolateral cell column of thoracic and upper lumbar cord, particularly middle to lower thoracic cord. Putative neurotransmitters, or their markers, in varicose fiber networks around SPN were identified. Nearly all hypotension-sensitive (Fos-IR) SPN were apposed by varicose fibers immunoreactive for tyrosine hydroxylase, serotonin, substance P, or enkephalin. Neuropeptide Y (NPY)- or phenylethanolamine-N-methyl transferase (PNMT)-IR varicose fibers apposed Fos-IR SPN in the upper and middle thoracic spinal cord, but in lower thoracic segments some Fos-IR SPN lacked these appositions. In thoracic segment 12, 51% +/- 5% of Fos-IR SPN (n = 9 rats) lacked PNMT contacts and 25% +/- 3% of Fos-IR SPN (n = 8 rats) lacked NPY contacts. In contrast to other chemically defined afferents, galanin-IR varicose fibers apposed fewer than half of the Fos-IR SPN in the middle to lower thoracic cord. Neurotransmitters/neuromodulators that might influence the activity of SPN acting in the baroreflex-mediated control of blood pressure have been identified. Uniformity in the neurochemistry of some fibers making connections with Fos-IR SPN, regardless of their segmental origin, suggests that common sets of neurons provide convergent inputs to all hypotension-sensitive SPN. Other fibers show topographic differences in their contacts with Fos-IR SPN, suggesting that subgroups of hypotension-sensitive SPN are targeted by particular neuron groups. 相似文献
79.
Gaston RC Arnold CD Ahluwalia BD Sonnad JR Macdurmon GW Gold MA Parry CK Montebello JF Mayr NA 《Clinical nuclear medicine》2002,27(7):494-498
An unexpected elevated postimplant radiation survey is described in an elderly patient with an interstitial low-dose-rate iridium-192 (Ir-192) needle implant for endometrial cancer. The elevated activity was related to prolonged clearance of Tl-201 from a cardiac study that had been performed 7 days earlier. The Tl-201 accumulated in the soft tissue, particularly the colon, resulting in increased survey readings over the abdomen and raising concern that an Ir-192 source remained within the patient. This case shows that delayed excretion of a diagnostic radionuclide agent can cause elevated activity high enough to confound postradiotherapy implant survey readings. The estimated surface exposure from a single iridium source left in the pelvis was determined using a phantom study. Possible factors causing decreased excretion of Tl-201 in a patient with heart disease, arteriosclerotic vascular disease, previous pelvic radiation therapy, and a brachytherapy procedure are discussed. A preloading radiation survey is recommended in patients who have had previous nuclear medicine studies involving radionuclides with long half-lives. 相似文献
80.
Risk factors for traumatic and bloody lumbar puncture in children with acute lymphoblastic leukemia 总被引:5,自引:0,他引:5
Howard SC Gajjar AJ Cheng C Kritchevsky SB Somes GW Harrison PL Ribeiro RC Rivera GK Rubnitz JE Sandlund JT de Armendi AJ Razzouk BI Pui CH 《JAMA》2002,288(16):2001-2007
Context Traumatic or bloody lumbar puncture (LP) reduces the diagnostic value of the procedure and may worsen the outcome of patients with acute lymphoblastic leukemia (ALL). Little is known about the risk factors for traumatic and bloody LP. Objectives To determine the risk factors for traumatic and bloody LP. Design, Setting, and Patients Retrospective cohort study of 956 consecutive patients with newly diagnosed childhood ALL who were treated at a pediatric cancer center between February 1984 and July 1998. Interventions All patients underwent a diagnostic LP followed by a median of 4 LPs to instill intrathecal chemotherapy. Main Outcome Measure Traumatic LP was defined as an LP in which cerebrospinal fluid contained at least 10 red blood cells (RBCs) per microliter and bloody LP as one in which the cerebrospinal fluid contained at least 500 RBCs per microliter. Results Of the 5609 LPs evaluated, 1643 (29%) were traumatic and 581 (10%) were bloody. The estimated odds ratios (ORs) and 95% confidence intervals (CIs) for traumatic LP were 1.5 (95% CI, 1.2-1.8) for black vs white race, 2.3 (95% CI, 1.7-3.0) for age younger than 1 year vs 1 year or older, 1.4 (95% CI, 1.2-1.7) for early vs recent (dedicated procedure area and general anesthesia) treatment era, 1.5 (95% CI, 1.2-1.8) for platelet count of 100 x 103/µL or more vs less than 100 x 103/µL, 10.8 (95% CI, 7.7-15.2) for short (1 day) vs longer (>15 days) interval since the previous LP, and 1.4 (95% CI, 1.1-1.8) for the least vs the most experienced practitioners. Analyses for bloody LP yielded similar results. Conclusions The unmodifiable risk factors for traumatic and bloody LP include black race, age younger than 1 year, a traumatic or bloody previous LP performed within the past 2 weeks, and a previous LP performed when the platelet count was 50 x 103/µL or less. Modifiable risk factors include procedural factors reflected in treatment era, platelet count of 100 x 103/µL or less, an interval of 15 days or less between LPs, and a less experienced practitioner. 相似文献