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31.
Drug scene roles and HIV risk   总被引:1,自引:0,他引:1  
Aims. Drug scenes (social and spatial drug-using and drug-selling environments) have complex role structures. Many drug injectors earn money or drugs as drug or syringe sellers, hit doctors (people who help others to inject) commercial sex workers, or in other roles. This paper aims to measure "role behaviors" of drug injectors; describe which drug injectors are more likely to engage in such role behaviors; and to determine whether roles are related to elements of HIV risk . Design. Cross-sectional study of drug injectors . Setting. Bushwick, a section of Brooklyn, New York, a major location for injection drug use and drug sales . Participants. Seven hundred and sixty-seven street-recruited drug injectors . Measurements. Participants were interviewed about their roles, behaviors, socio-demographics and risk networks; sera were collected and assayed for HIV and hepatitis B core antibody . Findings. Socio-demographic variables are related to role-holding in complex ways. Economic need is generally associated with engaging in drug-scene role behaviors. Holders of these roles are at greater behavioral and network risk for HIV and other blood-borne infections than are other drug injectors. They also engage in extensive communication with other drug users, including discussion of HIV risk reduction . Conclusion. Role behaviors can be measured in quantitative studies, and seem to be related to HIV risk. Role-holders may be strategic targets for risk-reduction campaigns. It seems feasible and advisable to measure drug scene role-holding in research on drug users.  相似文献   
32.
To examine whether increasing investment in needle/syringe exchange programs (NSPs) in the US would be cost-effective for HIV prevention, we modeled HIV incidence in hypothetical cases with higher NSP syringe supply than current levels, and estimated number of infections averted, cost per infection averted, treatment costs saved, and financial return on investment. We modified Pinkerton’s model, which was an adaptation of Kaplan’s simplified needle circulation theory model, to compare different syringe supply levels, account for syringes from non-NSP sources, and reflect reduction in syringe sharing and contamination. With an annual $10 to $50 million funding increase, 194–816 HIV infections would be averted (cost per infection averted $51,601–$61,302). Contrasted with HIV treatment cost savings alone, the rate of financial return on investment would be 7.58–6.38. Main and sensitivity analyses strongly suggest that it would be cost-saving for the US to invest in syringe exchange expansion.  相似文献   
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Aims We conducted a systematic review of studies reporting seroincidence of hepatitis C infection (HCV) in relation to shared syringes and drug preparation equipment among injection drug users (IDUs). We identified published and unpublished studies that met inclusion criteria. Design We estimated the relative contributions of shared syringes and drug preparation equipment to HCV transmission using random‐effects meta‐analysis, and analyzed potential sources of heterogeneity of effects among studies. Findings Syringe sharing was associated with HCV seroconversion [pooled risk ratio (PRR) = 1.94, 95% confidence interval (CI) 1.53, 2.46], as was sharing drug preparation containers (PRR = 2.42, 95% CI 1.89, 3.10), filters (PRR = 2.61, 95% CI 1.91, 3.56), rinse water (PRR = 1.98, 95% CI 1.54, 2.56), combinations of this equipment (PRR = 2.24, 95% CI 1.28, 3.93) and ‘backloading’, a syringe‐mediated form of sharing prepared drugs (PRR = 1.86, 95% CI 1.41, 2.44). Meta‐regression results showed that the association between syringe sharing and seroconversion was modified by HCV seroprevalence in the IDU populations. Conclusions The risk of hepatitis C infection through shared syringes is dependent upon hepatitis C infection seroprevalence in the population. The risk of hepatitis C infection through shared drug preparation equipment is similar to that of shared syringes. Because the infection status of sharing partners is often unknown, it is important for injection drug users to consistently avoid sharing unsterile equipment used to prepare, divide or inject drugs and avoid backloading with an unsterile syringe.  相似文献   
35.
The practice of elective penicillin skin testing could be compromised by the fact that patients, their parents, or their physicians remain reluctant to reuse penicillin-class antibiotics (PCAs) despite a negative evaluation by an allergist. This study addresses reuse of PCAs in a pediatric population after negative penicillin skin testing and drug challenge and factors associated with its reluctance. All children evaluated for a history of penicillin allergy at the CHU Sainte-Justine Allergy Clinic between January 1998 and June 2000 with negative skin testing and drug challenge were included in the study. A telephone survey was conducted between May and October 2002 to assess the perception of the initial reaction by the parents, subsequent use of antibiotics, and antibiotic-related adverse reactions. Among the 200 children selected, parents of 170 (85%) children completed the survey. Since the allergist evaluation, 130 (76%) children had received antibiotics. PCA was used in 59 (45%) children. Parents of 24 (18%) children refused PCAs because they still feared an adverse reaction. They were more likely to have been very frightened by their child's allergic reaction than other parents whose children had used PCAs (p = 0.008). Although elective penicillin skin testing is useful and safe in the pediatric population, a significant proportion of parents still refuse PCAs even though they are needed. Identification of parents that were very frightened by their children's allergic reactions and additional reassurance could improve this situation.  相似文献   
36.
Introduction: Women consider factors including safety and the psychological impact of their chosen location when deciding whether to give birth in hospital or at home. The same is true for women with high-risk pregnancies who may plan homebirths against medical advice. This study investigated women’s decision-making during high-risk pregnancies. Half the participants were planning hospital births and half were planning homebirths.

Methods: A qualitative study using semi-structured interviews set in a hospital maternity department in the UK. Twenty-six participants with high-risk pregnancies, at least 32 weeks pregnant. Results were analysed using systematic thematic analysis.

Results: Three themes emerged: perceptions of birth at home and hospital; beliefs about how birth should be; and the decision process. Both groups were concerned about safety but they expressed different concerns. Women drew psychological comfort from their chosen birth location. Women planning homebirths displayed faith in the natural birth process and stressed the quality of the birth experience. Women planning hospital births believed the access to medical care outweighed their misgivings about the physical environment.

Discussion: Although women from both groups expressed similar concerns about safety they reached different decisions about how these should be addressed regarding birth location. These differences may be related to beliefs about the birth process. Commitment to their decisions may have helped reduce cognitive stress.  相似文献   
37.
KIR3DL1 is one of the best-characterised inhibitory NK cell receptors. Unusually, one common allele at the 3DL1 locus encodes an activating receptor known as 3DS1. There is genetic evidence for a protective role of 3DS1 in certain viral diseases, but there has been uncertainty about expression of the 3DS1 protein. Using transfection, we show that surface expression of 3DS1 is reliant on the adaptor protein DNAX-activating protein 12 (DAP12). KIR3DS1 was recognised by the antibody Z27, a reagent that also detects KIR3DL1 but no other killer immunoglobulin-like receptor (KIR) molecule. Z27 stained 3DS1 on the surface of fresh circulating NK cells from 3DS1/3DS1 homozygotes. By double-staining with Z27 and DX9, an antibody specific for 3DL1, we obtained evidence that in 3DS1/3DL1 heterozygous donors significant numbers of NK cells express 3DS1 without co-expressing 3DL1 and that NK cells expressing both alleles are difficult to detect.  相似文献   
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39.

Background

Rectal carcinoids are increasing in incidence worldwide. Frequently thought of as a relatively benign condition, there are limited data regarding optimal treatment strategies for both localized and more advanced disease. The aim of this study was to summarize published experiences with rectal carcinoids and to present the most current data.

Methods

Following PRISMA guidelines, an electronic literature search performed of PubMed, Medline, Embase, and the Cochrane Library using the terms “rectum” or “rectal” AND “carcinoid” over a 20-year study period from January 1993 to May 2013. Non-English-language studies, animal studies, and studies of fewer than 100 patients were excluded. Study end points included demographic information, tumor features, intervention and outcomes. All included articles were quality assessed.

Results

Using the search parameters and exclusions as outlined above, a total of 14 articles were identified for detailed analysis. The quality of articles was low/moderate for all included scoring 9 to 17 of 27. The articles included 4,575 patients diagnosed with a rectal carcinoid. Approximately 80 % of tumors were <10 mm, 15 % 11–20 mm, and 5 % >20 mm. Eight percent of patients presented with regional lymph node metastases, and 4 % presented with distant metastases. Tumor size >10 mm, and muscular and lymphovascular invasion are independently associated with an increased risk of metastases. The 5-year survival was 93 % in patients presenting with localized disease and 86 % overall.

Conclusions

Small tumors up to 10 mm without any adverse features can be treated with endoscopic or local excision. The treatment of carcinoids between 10 and 20 mm is still contentious, but those up to 16 mm without adverse feature are suitable for local/endoscopic excision followed by careful histopathological assessment. Those >20 mm or with adverse features require radical surgery with mesorectal clearance in suitable patients.  相似文献   
40.

Background

The introduction of a combined-modality approach, which added chemotherapy to local therapy (surgery and radiotherapy), has been controversial. We present our experience of the efficacy of neoadjuvant chemotherapy in patients with high-risk sarcomas and evaluate the benefit of intra-arterial (IA) chemotherapy.

Patients and methods

Forty patients with intermediate to high-grade soft tissue sarcomas (STS) were treated with neoadjuvant chemotherapy from 1994 to 2001 at the Institut Curie. Thirty-seven patients had localized tumours. Neoadjuvant intravenous (IV) chemotherapy consisted of 4–6 cycles of treatment (mainly CYVADIC, MAID). Sixteen patients (40%) received 2 cycles of IA chemotherapy with a combination of adriamycin and cisplatin. Radiotherapy was delivered in an adjuvant setting.

Results

All patients underwent limb-sparing surgical resection after neoadjuvant therapy and pathologic assessment of tumour necrosis was performed on the resected specimens. Two groups of tumours were analysed: 1–95% (28 cases), and 95–100% (10 cases) of pathological necrosis, with a survival benefit in the group with more than 95% necrosis (p = 0.07). IA chemotherapy was superior to IV chemotherapy in terms of the necrosis rate (p = 0.045). With a median follow-up of 51 months, the 2-year overall survival rate was 90% for localized tumours.

Conclusion

Neoadjuvant chemotherapy can be considered to be effective in the treatment of STS. This study demonstrates the benefit of neoadjuvant therapy for patients with a high necrosis rate (very clear tendency) and the contribution of IA chemotherapy to the response rate, but with no survival advantage.  相似文献   
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