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71.
IntroductionSuprapubic catheterization (SPC) is a fundamental skill required of urology trainees. A lack of affordable simulation models and unpredictability of bedside SPCs limit experiential learning opportunities. Our objective was to develop and initially validate a re-usable, low-cost, ultrasound (US)-compatible SPC simulator for acquiring skills that transfer to the bedside.MethodsThe model was constructed using six components. Staff urologists and interventional radiologists (IRs) conducted a SPC and rated the model on three domains with multiple subcategories on a five-point Likert scale: anatomic realism; usefulness as a training tool; and global/overall reaction. Participants in our first-year urology “boot camp” received SPC training, practiced, and were evaluated via an objective structured clinical examination (OSCE). Staff ratings and OSCE scores determined the model’s initial face and content validity.ResultsTwelve staff physicians participated in the study. The mean scores for urologists and IRs, respectively, were: anatomical realism: 4.10 and 3.70; usefulness as a training tool: 4.23 and 4.24; and overall reaction: 4.40 and 4.44. Staff strongly agreed that the model should be incorporated into the residency curriculum. Over the past four years, 25 boot camp participants scored a mean of 99.7% (±1.8) on the OSCE, with high technical performance and entrustment scores (4.8 and 4.7, respectively). The model cost $55 CAD.ConclusionsThis novel, multiple-use, low-cost, easily reproducible US-compatible SPC simulator demonstrated initial face and content validity via high staff urologist and IR ratings and OSCE scores of first-year urology residents. Additional research is required for construct validation.  相似文献   
72.
Human transmission of SARS-CoV-2 and emergent variants of concern continue to occur globally, despite mass vaccination campaigns. Public health strategies to reduce virus spread should therefore rely, in part, on frequent screening with rapid, inexpensive, and sensitive tests. We evaluated two digitally integrated rapid tests and assessed their performance using stored nasal swab specimens collected from individuals with or without COVID-19. An isothermal amplification assay combined with a lateral flow test had a limit of detection of 10 RNA copies per reaction, and a positive percent agreement (PPA)/negative percent agreement (NPA) during the asymptomatic and symptomatic phases of 100%/100% and 95.83/100%, respectively. Comparatively, an antigen-based lateral flow test had a limit of detection of 30,000 copies and a PPA/NPA during the asymptomatic and symptomatic phases of 82.86%/98.68% and 91.67/100%, respectively. Both the isothermal amplification and antigen-based lateral flow tests had optimized detection of SARS-CoV-2 during the peak period of transmission; however, the antigen-based test had reduced sensitivity in clinical samples with qPCR Ct values greater than 29.8. Low-cost, high-throughput screening enabled by isothermal amplification or antigen-based techniques have value for outbreak control.  相似文献   
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OBJECTIVES: To investigate the relationship of specific nutrients and food items with oral precancerous lesions among tobacco users.
DESIGN: A population-based case-control study. SETTING: Villages in Palitana taluk of Bhavnagar district, Gujarat, India.
SUBJECTS AND METHODS: An interviewer-administered food frequency questionnaire, developed and validated for this population, was used to estimate nutrient intake in blinded, house-to-house interviews. Among 5018 male tobacco users, 318 were diagnosed as cases. An equal number of controls matched on age (±5 years), sex, village, and use of tobacco were selected.
MAIN OUTCOME MEASURES: Odds ratios (OR) from multiple logistic regression analysis controlling for relevant variables (type of tobacco use and economic status).
RESULTS: A protective effect of fibre was observed for both oral submucous fibrosis (OSF) and leukoplakia, with 10% reduction in risk per g day-1 ( P < 0.05). Ascorbic acid appeared to be protective against leukoplakia with the halving of risk in the two highest quartiles of intake (versus the lowest quartile: OR = 0.46 and 0.44, respectively; P < 0.10). A protective effect of tomato consumption was observed in leukoplakia and a suggestion of a protective effect of wheat in OSF.
CONCLUSION: In addition to tobacco use, intake of specific nutrients may have a role in the development of oral precancerous lesions.  相似文献   
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The Stages of Change (SOC) model was used to implement and evaluate a condom promotion intervention for HIV-positive and at-risk women who were recruited from clinic and community settings in Baltimore and Philadelphia. Participants were assigned to receive standard reproductive health services or enhanced services (standard plus SOC peer advocate intervention). Women who had a main partner at baseline and at a 6-month follow-up were included in the analysis (70 HIV positive, 471 at risk). Compared with the standard group, HIV-positive women in the enhanced group were significantly more likely to have progressed in the SOC model or to have maintained consistent condom use, and less likely to have relapsed or stayed in the precontemplation stage. Among the at-risk women, exposure to the intervention was associated with being at a higher SOC and being less likely to relapse relative to the standard group. The SOC model has promise for use in social and public health service settings that serve women at risk or living with HIV.  相似文献   
79.
Naratriptan: biological profile in animal models relevant to migraine   总被引:2,自引:0,他引:2  
The biological profile of naratriptan (N-methyl-3-(1-methyl-4-piperidinyl)-1H-indole-5-ethane-sulphona-mide), a novel 5HT1B/1D receptor agonist, was investigated in a variety of experimental models of relevance to migraine. Naratriptan has high affinity for human recombinant 5HT1B and 5HT1D receptors (pKi = 8.70.03 and 8.30.1, respectively) and causes contractions of dog isolated basilar and middle cerebral artery (EC50 values of 0.11 and 0.07 M, respectively). Naratriptan causes small contractions of human isolated coronary arteries (EC50 value of 0.17 M; maximum contraction equivalent to 33% of 5HT maximum). In anaesthetized dogs, naratriptan causes selective vasoconstriction of the carotid arterial bed (CD50 dose = 193 g kg−1) and, in anaesthetized rats, naratriptan selectively inhibits neurogenic plasma protein extravasation in the dura (ID50 = 4.1 g kg−1). In a variety of antinociceptive tests, naratriptan has no effect even at high doses. In conscious rats and dogs, naratriptan has high oral bioavailability (71% and 95%, respectively). The data show that naratriptan is a selective agonist at 5HT1B/1D receptors, with a pharmacological profile very similar to that of sumatriptan, albeit 2-3 fold more potent. These observations, coupled with high oral bioavailability in animals, suggest that naratriptan has the profile of an orally effective anti-migraine drug.  相似文献   
80.

Background

The 5‐year overall survival rate for patients with sinonasal cancers has remained around 50% for the last 3 decades. Prior studies on head and neck cancers have suggested that 1 reason for poor survival is the frequent development of second primary malignancies (SPMs). The purpose of this study is to assess overall and site‐specific risks of SPM following treatment of sinonasal malignancy.

Methods

A retrospective, population‐based cohort study was performed on 2614 patients in the Surveillance, Epidemiology, and End Results (SEER) database who were diagnosed with primary sinonasal malignancy between 1973 and 2014. Standardized incidence ratios (SIRs) and absolute excess risks (AERs) were calculated to assess risk of SPM relative to incidence in the general population.

Results

A total of 422 (16.1%) patients with primary sinonasal malignancies developed a total of 480 SPMs. This cohort had a significantly higher frequency of SPMs than expected in the general population (SIR 1.32; 95% confidence interval [CI], 1.20 to 1.44; AER 53.41). Site‐specific analyses of SIRs suggested highest risk of malignancy in the sinonasal tract (SIR 75.64; 95% CI, 53.53 to 103.83; AER 17.22), followed by bone, eye and orbit, oral cavity and pharynx, and lung and mediastinum.

Conclusion

Patients with history of sinonasal cancer are at significantly increased risk of developing an SPM. Careful monitoring for development of additional tumors may be warranted.
  相似文献   
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