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81.
This article is Part I of a three-part series that reports the quantitative findings that investigated if an externship program had a long-term effect on new graduates' role socialization to the healthcare environment. Two groups were compared: a group of 26 registered nurses who had participated in the externship program and a matched cohort group of 26 nurses who had not participated in an externship program at this institution or any other clinical agency. No statistically significant differences were found between the groups on the variables of job satisfaction and sense of belonging. In contrast, the analysis did demonstrate significant differences in the mean scores for professionalism and role socialization between the two groups; however, the average score on each scale for those nurses in the cohort group was higher as compared to the average scale score of the nurses who had been nurse externs.  相似文献   
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BACKGROUND: The duration of protection afforded by vaccines represents a critical test of their utility as public health interventions. Some vaccines induce long-term immunity, while others require booster doses. Vaccines that induce long-term protection are usually characterized by the generation of immune memory. Recent trials of a quadrivalent (types 6, 11, 16, 18) human papillomavirus (HPV) vaccine have demonstrated high efficacy through 5 years of follow-up. We evaluated the extent to which the vaccine is able to generate HPV type-specific immune memory. METHODS: A total of 552, 16-23-year-old women were enrolled in a double-blind, placebo-controlled study. At enrollment, subjects were randomized in a 1:1 ratio to receive three-dose regimens of quadrivalent HPV vaccine or placebo with 3 years' follow-up. A subset of 241 subjects (n=114 in the quadrivalent HPV vaccine group and n=127 in the placebo group) underwent 2 further years of follow-up. All extension subjects received quadrivalent HPV vaccine at month 60 to examine the extent of immune memory in response to the primary vaccination series. RESULTS: Serum anti-HPV levels declined post-vaccination, but reached a plateau at month 24 that remained stable through month 60. Administration of a challenge dose of vaccine induced a classic anamnestic response, with anti-HPV levels 1 week post-challenge reaching levels observed 1 month following the completion of the three-dose primary series. At 1 month post-challenge, anti-HPV responses were higher than those observed 1-month post-dose 3. DISCUSSION: A three-dose regimen of quadrivalent HPV vaccine induces high efficacy and stable anti-HPV levels for at least 5 years. Vaccination also induces robust immune memory. These findings suggest that the efficacy of this vaccine will be long lasting.  相似文献   
83.
BACKGROUND: Endoscopic ultrasonography, both conventional and interventional, has been used increasingly during the past 20 years and is deemed a safe technique. Its complication rate, however, has been studied to only a limited extent. This multicentre investigation sought to establish the complication rate for a large number of endoscopic ultrasonography procedures. METHODS: By means of a questionnaire, we collected data from six centres on the number of endoscopic ultrasonography examinations performed and divided them into conventional and interventional examinations of the upper and lower gastrointestinal tract. Information was obtained on technical modalities such as instruments and sedation and, for interventional endoscopic ultrasonography, indications, pre-procedural exams and technical details (needle calibre, number of passes) had to be specified. Complications were classified as mild, moderate, severe or fatal and their onset as immediate, early or late. Variables that entered into the analysis of complication rate included type of endoscopic ultrasonography instrument used, type and site of lesion biopsied, number of needle passes and operator experience. RESULTS: Eleven thousand five hundred thirty nine endoscopic ultrasonographic procedures were reported, of which 10,731 were conventional and 808 interventional. No deaths occurred; there were 14 (0.12%) complications, 5 (0.046%) of them following conventional endoscopic ultrasonography and 9 (1.11%) after interventional endoscopic ultrasonography. Seven complications were mild, four moderate and three severe. CONCLUSIONS: Both conventional and interventional endoscopic ultrasonography were confirmed to be acceptably safe techniques.  相似文献   
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The purpose of this study was to assess the influence of pupil size and optical blur on measurements obtained with isolated-check visual evoked potential (icVEP). Two stimulus conditions of icVEP, +15 and −15% contrasts, were studied in normal subjects with normal (N), miotic (M), and dilated (D) pupils. The effects of optical blur were studied in subjects with normal pupil. Response to visual stimuli was quantified by a signal-to-noise (SNR) ratio. In 30 normal subjects, the mean age was 26.0 ± 3.4 years. Mean pupil diameters were N = 4.2 ± 0.6 mm, M = 2.7 ± 0.6 mm, and D = 7.3 ± 0.9 mm. For both +15 and −15% contrast levels, mean SNR values were reduced for dilated and constricted pupils when compared with normal pupils. Mean SNR values for optical blur with a +2 or +3 diopter lens placed over the distance correction were reduced when compared with SNR measurements obtained with best-corrected visual acuity under both +15 and −15% contrast levels. Statistical significance was found in comparisons of N versus M (P < 0.001) and N versus D (P = 0.002) for +15 and −15% contrast conditions, respectively. No statistical difference was seen for M versus D (P = −0.435). The effect of optical blur was statistically significant when compared to the normal pupils with best-corrected vision (P < 0.001). No statistically significant difference was found comparing +2 and +3 diopters lenses for optical blur testing. Visual evoked potential values are influenced by pupillary constriction and dilation, as well as optical blur. When obtaining icVEP measurements, the influence of pupil size and optical blur should be kept in mind for accurate interpretations.  相似文献   
87.
OBJECTIVE: To determine the best measure of fetal nasal bone hypoplasia for trisomy 21 risk assessment in the second trimester. METHODS: This was a prospective, observational study performed at a single institution between February 2003 and December 2005. Fetuses with nasal bone length recorded sonographically between 16 and 20.9 weeks and known karyotype were included. Definitions of nasal bone hypoplasia assessed included: non-visualized nasal bone, nasal bone < 10th percentile, nasal bone < 2.5th percentile, biparietal diameter/nasal bone ratio >or= 10 and >or= 11 and nasal bone multiples of the median (MoM) 相似文献   
88.
In a randomized study, caspofungin was compared with amphotericin B for the treatment of invasive candidiasis in a total of 239 adults from 56 sites in 20 countries. This study provided a unique opportunity to assess the frequency and outcome of invasive candidiasis caused by different Candida species worldwide, and the results are presented here. Efficacy was primarily assessed at the end of intravenous therapy using a modified intent-to-treat (MITT) analysis. This analysis was performed on 224 of the 239 patients enrolled in the study. Attempts were made to collect baseline Candida isolates from all patients for species identification at a central laboratory. Yeasts were identified to the species level using two commercial systems and microscopic examination. Viable baseline isolates were recovered from 210 of the 224 (94%) patients included in the MITT analysis. Candida albicans was the most frequently isolated species in all regions and was responsible for 45% of cases overall. Nevertheless, the majority of cases of infection were caused by non-albicans Candida species. In the USA and Canada, Candida glabrata was the second most commonly isolated pathogen (18%). In contrast, Candida parapsilosis and Candida tropicalis accounted for 55% of cases in Latin America. Outcomes were comparable for patients treated with caspofungin (74% overall; 64% and 80% for infections due to Candida albicans and non-albicans species) and amphotericin B (62% overall; 58% and 68% for infections due to Candida albicans and non-albicans species), and were generally similar across continents. The distribution of Candida species isolated from patients enrolled in a clinical trial may not be representative of pathogens causing invasive candidiasis in the general population. Nevertheless, our findings may affect the regional choice of empirical antifungal therapy for seriously ill patients with suspected or documented invasive candidiasis since different Candida species have varying susceptibility to conventional antifungal drugs.  相似文献   
89.
Laparoscopic liver resection(LLR) has been progressively developed along the past two decades. Despite initial skepticism, improved operative results made laparoscopic approach incorporated to surgical practice and operations increased in frequency and complexity. Evidence supporting LLR comes from case-series, comparative studies and meta-analysis. Despite lack of level 1 evidence, the body of literature is stronger and existing data confirms the safety, feasibility and benefits of laparoscopic approach when compared to open resection. Indications for LLR do not differ from those for open surgery. They include benign and malignant(both primary and metastatic) tumors and living donor liver harvesting. Currently, resection of lesions located on anterolateral segments and left lateral sectionectomy are performed systematically by laparoscopy in hepatobiliary specialized centers. Resection of lesions located on posterosuperior segments(1, 4a, 7, 8) and major liver resections were shown to be feasible but remain technically demanding procedures, which should be reserved to experienced surgeons. Hand-assisted and laparoscopy-assisted procedures appeared to increase the indications of minimally invasive liver surgery and are useful strategies applied to difficult and major resections. LLR proved to be safe for malignant lesions and offers some short-term advantages over open resection. Oncological results including resection margin status and long-term survival were not inferior to open resection. At present, surgical community expects high quality studies to base the already perceived better outcomes achieved by laparoscopy in major centers' practice. Continuous surgical training, as well as new technologies should augment the application of lap-aroscopic liver surgery. Future applicability of new technologies such as robot assistance and image-guided surgery is still under investigation.  相似文献   
90.
The efficacy of the quadrivalent Human Papillomavirus (HPV) vaccine is thought to be mediated by humoral immunity. We evaluated the correlation between quadrivalent HPV vaccine-induced serum anti-HPV responses and efficacy. 17,622 women were vaccinated at day 1, and months 2 and 6. At day 1 and at 6-12 months intervals for up to 48 months, subjects underwent Papanicolaou and genital HPV testing. No immune correlate of protection could be found due to low number of cases. Although 40% of vaccine subjects were anti-HPV 18 seronegative at end-of-study, efficacy against HPV 18-related disease remained high (98.4%; 95% CI: 90.5-100.0) despite high attack rates in the placebo group. These results suggest vaccine-induced protection via immune memory, or lower than detectable HPV 18 antibody titers.  相似文献   
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