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971.
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973.
While epidemiological investigations have documented elevated health harms associated with public injecting, further ethnographic research focused specifically on public injecting settings is required to develop greater understanding of how these environments influence the production of drug-related harm. We undertook preliminary ethnographic research, incorporating a structured environmental survey, observations and interviews with 50 local injectors, in Vancouver's Downtown Eastside (DTES). Our study aimed to document the physical locations and social context of public injecting settings, exploring how such venues interplay with injection-related health risks. Findings show that DTES public injecting locations comprise a large network of alleyways, which are often unsanitary and constrain efforts to inject in a hygienic fashion. Due to fears of being intercepted by the police, physically assaulted, or robbed, injectors are preoccupied with "hurrying and worrying" when injecting in public. Although individuals are concerned with matters of hygiene and avoiding infections associated with injecting, the perceived risks of public injection settings are primarily related to the presence of street predators and the police. Ecological features of public injecting environments serve to complicate the task of injecting, encourage 'rushing' during the injection process, and decrease the likelihood that public injectors will employ safer injecting practices. Future interventions must specifically target these micro risk environments. Innovative strategies are urgently needed to ensure that police operations in the open drug scene do not compromise public injectors' efforts to protect their health. Additionally, structural factors which perpetuate the large public injecting scene should be addressed through policy interventions that increase access to housing and public toilets as well as expanding the scope and capacity of the local drug consumption facilities.  相似文献   
974.
The number of fluctuations in skin conductance per second has been described as a potential tool for monitoring postoperative pain. More recently, the surgical stress index has shown promising correlations with intra-operative painful stimuli. We compared both methods for their ability to assess postoperative pain, in 100 postoperative patients who were also asked to quantify their level of pain at different time points in the recovery room. The number of fluctuations per second and surgical stress index were significantly different between pain scoring ≤ 5/10 and > 5/10 on a numeric rating scale (mean (SE) number of fluctuations per second 0.12 (0.02) vs 0.21 (0.03), respectively; p = 0.017, and surgical stress index 57 (1.4) vs 64 (1.9) points, respectively; p = 0.001). Both number of fluctuations in skin conductance per second and surgical stress index identified timepoints with moderate to severe pain with only moderate sensitivity and specificity.  相似文献   
975.
Bryan N  Rhodes NP  Hunt JA 《Biomaterials》2009,30(2):180-188
A host-derived hydrogel has been designed and validated as an entirely autologous, injectable delivery system for cells with potential for cell-based therapies and tissue engineering applications. Each individual has components in their blood from which can be formed a mechanically stable hydrogel having the capacity to maintain cellular phenotype and support cellular proliferation of multiple cell types through several culture passages ex vivo. The hydrogel can be triggered to gel at the time of implantation into the patient through an injection system that facilitates a liquid injection of components of the donor plasma and cells into the site of interest. This results in stable ectopic tissue formation at the site of implantation. Our studies have demonstrated excellent integration of the neotissue with host tissues with maintenance of the phenotype of implanted cells whilst observing minimal host innate immune cell recruitment. These findings could provide the fundamental basis for new hydrogel-based biomaterial therapies, overcoming the histocompatibility factors associated with implantable biomaterials whilst providing a stable three dimensional medium for cellular growth both in vivo and ex vivo.  相似文献   
976.
BACKGROUND: Although syringe distribution is effective in preventing HIV transmission among injecting drug users (IDUs), there is little evidence on the required coverage to substantially reduce HIV transmission. METHODS: A mathematical model is developed to explore the relationship between the endemic HIV prevalence among IDUs and the coverage of syringe distribution. Data from IDU populations in the United Kingdom and Belarus are used to explore the implications of increasing coverage and the effect of changes in other behaviors. RESULTS: Projections suggest that there is a coverage threshold, which, if reached, could lead to substantial decreases in HIV prevalence. The threshold largely depends on the frequency that IDUs inject and (safely) reuse their syringes, and corresponds to less than 4 syringe-sharing events per IDU per month. Other factors, such as the injecting cessation rate and efficacy of syringe cleaning, only have substantial impact near threshold coverage levels. CONCLUSIONS: Our results support a policy of increasing the coverage of syringe distribution but highlight the difficulty in producing a universal coverage target. Great public health benefit could be conferred by encouraging the safe reuse of an IDU's own syringes and small stable injecting groups. Policies that discourage this will negate the impact of syringe distribution interventions.  相似文献   
977.
Recruitment to nursing programmes is becoming increasingly difficult. At Staffordshire University we applied to a project called Higher Education Full Circle for the funding of paid student ambassadors to help with our nurse recruitment programmes. Two nursing students took on the role while continuing with their training. This article discusses the work of the student ambassadors.  相似文献   
978.
979.
To determine whether intranasal administration (iN) of recombinant human insulin-like growth factor-1 (rhIGF-1) provides neuroprotection to the neonatal rat brain following cerebral hypoxia-ischemia (HI), two doses of rhIGF-1 (50 μg at a 1 h interval) were infused into the right naris of postnatal day 7 (P7) rat pups with or without a prior HI insult (right common carotid artery ligation, followed by an exposure to 8% oxygen for 2 h). Our result showed that rhIGF-1 administered via iN was successfully delivered into the brain 30 min after the second dose. In the following studies rhIGF-1 was administered to P7 rat pups at 0, 1 or 2 h after HI at the dose described above. Pups in the control group received cerebral HI and vehicle treatment. Pups that underwent sham operation and vehicle treatment served as the sham group. Brain pathological changes were evaluated 2 and 15 days after HI. Our results showed that rhIGF-1 treatment up to 1 h after cerebral HI effectively reduced brain injury as compared to that in the vehicle-treated rats. Moreover, rhIGF-1 treatment improved neurobehavioral performance (tested on P5–P21) in juvenile rats subjected to HI. Our results further showed that rhIGF-1 inhibited apoptotic cell death, possibly through activating the Akt signal transduction pathway. rhIGF-1 enhanced proliferation of neuronal and oligodendroglial progenitors after cerebral HI as well. These data suggest that iN administration of IGF-1 has the potential to be used for clinical treatment.  相似文献   
980.

OBJECTIVE

To compare the detection of asymptomatic renal cell carcinoma (RCC) in an executive health programme (EHP) that uses traditional methods of screening (history, physical examination and urine analysis) to programmes that screen by renal imaging.

PATIENTS AND METHODS

We retrospectively reviewed case records from patients undergoing executive health examinations at Mayo Clinic between 1 January 2002 and 30 September 2007.

Results

Of 32 310 patients, 18 RCCs were detected; of these, 13 (72%) were detected by the EHP and five (28%) were missed by the initial EHP screening process but subsequently discovered within 4–24 months. Of the 13 detected through the EHP, eight were discovered incidentally, two because of symptoms, and three because of asymptomatic microscopic haematuria (AMH). Of the 13, 12 were classified as early‐stage cancers (Stage I). By contrast, of the five cancers missed by the EHP screening process, two were diagnosed because of the development of symptoms and only one was classified as Stage I. To date, two of these patients whose cancers were undetected by the EHP developed metastasis and one of them has died. Both had been followed in the EHP for years and neither had MH in multiple specimens.

CONCLUSION

Our EHP follows standard policy and relies on a history, physical examination and urine analysis to decide who to evaluate for asymptomatic RCC. This practice missed >70% of the potentially diagnosable cancers. The patients with RCCs that were discovered initially by the EHP fared better than those whose diagnosis was delayed. Our detection rate of four per 10 000 was only a fraction of those reported by programmes using imaging as a screening tool. The logic behind our current approach to the early detection of asymptomatic RCC needs to be reassessed. AMH is coincidental in most cases and patients could forego imaging if they are unsuitable candidates for screening. However, AMH will miss most treatable cancers and is not an appropriate screening test for an early detection programme. In the absence of reliable biomarkers, renal imaging should be the primary screening tool for detecting asymptomatic RCC in informed, clinically suitable individuals enrolled in an early detection programme.  相似文献   
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