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This paper discusses the design and initial progress made with a virtual learning environment to help student nurses develop an understanding of cultural awareness and globalization. Using a Web-based application the Virtual Exchange Project was designed to facilitate study-elsewhere experiences located in the student's own setting. Promotion of the United Nations' Millennium Development goals provided an opportunity for student nurses to explore changes in global health and disease patterns, nursing education and systems of nurse regulation in the United Kingdom and Australia. A pedagogical framework created for this activity acknowledges the social and academic identities that learners often use, when working together in a virtual environment. The architecture of the Virtual Exchange supports local conversations about nurse education and health and social issues across hemispheres.  相似文献   
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PURPOSE: The specific aims of the study were to 1) determine what effects dose-dependent rope jumping had on os calcis stiffness index (OCSI) and 2) determine whether OCSI values measured by quantitative ultrasound (QUS) were dependent or independent of the values of bone mineral content (BMC) determined by dual energy x-ray absorptiometry (DXA) at the lumbar spine and proximal femur (femoral neck; greater trochanter). METHODS: Upon study entry, girls were randomly assigned to either one of two treatment groups (high volume; low volume) or a control group. Thirty-seven high school girls were recruited to participate in the study. QUS and DXA measurements were made at baseline and at 4-month follow-up. Students in the high-volume and low-volume groups jumped rope for 10 and 5 min, respectively. RESULTS: The follow-up mean OCSI values for the high-volume, low-volume, and control conditions were 103.95 +/- 12.55, 102.09 +/- 12.70, and 99.05 +/- 9.84, respectively. A statistically significant difference (P = 0.033) was identified between the high-volume and control groups. Baseline and follow-up OCSI values were significantly correlated with baseline and follow-up BMC measures of the femoral neck (r = 0.60, r = 0.59), greater trochanter (r = 0.47, r = 0.40), and lumbar spine (r = 0.56, r = 0.56). CONCLUSIONS: High-volume rope jumping increases the OCSI more than the control condition in postpubescent girls. Furthermore, the OCSI measured by QUS is moderately related to proximal femur and lumbar spine BMC measured by DXA.  相似文献   
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OBJECTIVE: Conventional transurethral resection of the prostate (TURP) uses a monopolar electrocautery system in which the current passes from the active electrode through the patient's body towards the return plate and may cause distant negative effects. In this study a new developed resection device, the Vista system, using a bipolar electrocautery system and 0.9% sodium chloride solution for irrigation, was evaluated in an ex-vivo model. METHODS: The modified model of the isolated blood perfused kidney was used to determine cutting qualities, ablation rate, blood loss and coagulation depth of the bipolar resectoscope. After ablating the renal tissue of a perfused kidney in a surface area, blood loss was semiquantitatively determined. Afterwards samples were taken and processed for histological evaluation of the coagulation depth. We compared the new bipolar resection device against a conventional monopolar resectoscope. RESULTS: We found good cutting qualities of the bipolar resectoscope although it is more difficult to start a cut. The ablation rate is determined by the width of the electrode and is similar to the standard device (30 cm(2)/min). The bleeding is reduced with increasing output powers (26.13 +/- 6.15 g/min (level 5); 20.49 +/- 5,47 g/min (level 6); 13.16 +/- 5,47 g/min (level 7); 10.43 +/- 4.76 g/min (level 8) and lower compared to a conventional monopolar resectoscope (17.08 +/- 4.47 g/min). The coagulation depth increases with higher output powers but is reduced compared to the standard device (118 +/- 22 microm (level 5); 121 +/- 23 microm (level 6); 141 +/- 62 microm (level 7); 163 +/- 30 microm (level 8) versus 287 +/- 57 (monopolar resectoscope)). CONCLUSION: Our results with the bipolar resection device for TURP suggest that it may offer an alternative to conventional TURP. As active and the return electrode are placed on the resectoscope, high current densities are achieved locally and complications caused by distant negative effects of the current are theoretically reduced in vivo. Furthermore the risk of TUR syndrome is theoretically eliminated by using physiological sodium chloride solution for irrigation. To prove the clinical significance of our ex-vivo findings, clinical studies including large numbers of patients have to be performed.  相似文献   
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目的 对焦虑抑郁压力量表(ADDI-27)进行汉化,并检验其在医学生焦虑抑郁压力评价中的信效度。 方法 通过翻译、回译等过程后确定中文版焦虑抑郁压力量表;选取山东某综合性大学医学部学生实施一般资料的问卷调查和焦虑抑郁压力量表评定;采用SPSS 24.0进行信度检验(Cronbachs α系数、分半信度系数)、探索性因子分析以及量表在各维度得分上的区分效度检验。 结果 共收集了404名医学大学生的信息,焦虑抑郁压力量表的Cronbachs α系数为0.907,分半信度系数为0.863;各因子得分上均具有较好的区分效度(P均<0.001),探索性因子分析共抽取3个因子,各因子所包含条目与原量表相同。 结论 焦虑抑郁压力量表具有较好的信度和效度,在医学大学生群体中被证实是有效、可行的。  相似文献   
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OBJECTIVES: Pathological and biochemical features of prostate cancers detected on repeat biopsies in men with total PSA level between 2.0 and 4 ng/ml were evaluated and compared to those cancers detected on first biopsy. METHODS: 315 men with PSA level between 2.0 and 4 ng/ml underwent transrectal ultrasound guided sextant biopsy and two additional transition zone biopsies (Octant Biopsy). All subjects whose biopsy samples were negative for prostate cancer underwent a repeat biopsy after 6 weeks. Those with clinically localized cancers were offered surgery or radiation therapy. Pathological and clinical features of patients diagnosed with prostate cancer on initial and repeat biopsy were compared. RESULTS: Cancer detection rates on first and second biopsy were 24% (75/315) and 13% (29/224), respectively. Overall, of patients with clinically localized disease (83% of cancers detected), 87% underwent radical prostatectomy, 11% opted for radiation therapy and 2% opted for watchful waiting. Cancers found in the first biopsy group were more multifocal (p = 0.01) while cancers found on second biopsy were more located in the apical-dorsal region (p = 0.003). No significant differences were noted with respect to extracapsular extension, seminal vesical invasion, positive margins, final pathological stage, Gleason score, percentage Gleason grade 4/5, serum PSA and patient age between first and second biopsy. CONCLUSIONS: With an octant biopsy regime, biochemical and pathological features of cancers detected on initial and repeat biopsy in the PSA range 2.0 to 4 ng/ml are comparable in terms of PSA, grade, stage and cancer volume suggesting identical cancer characteristics, thus advocating for a repeat prostate biopsy in case of a negative finding on initial biopsy.  相似文献   
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OBJECT: The goal of this study was to determine the risk of adverse outcomes after contemporary surgical treatment of meningiomas in the US and trends in patient outcomes and patterns of care. METHODS: The authors performed a retrospective cohort study by using the Nationwide Inpatient Sample covering the period of 1988 to 2000. Multivariate regression models with disposition end points of death and hospital discharge were used to test patient, surgeon, and hospital characteristics, including volume of care, as outcome predictors. Multivariate analyses revealed that larger-volume centers had lower mortality rates for patients who underwent craniotomy for meningioma (odds ratio [OR] 0.74, 95% confidence interval [CI] 0.59-0.93, p = 0.01). Adverse discharge disposition was also less likely at high-volume hospitals (OR 0.71, 95% CI 0.62-0.80, p < 0.001). With respect to the surgeon caseload, there was a trend toward a lower rate of mortality after surgery when higher-caseload providers were involved, and a significantly less frequent adverse discharge disposition (OR 0.71, 95% CI 0.62-0.80, p < 0.001). The annual meningioma caseload in the US increased 83% between 1988 and 2000, from 3900 patients/year to 7200 patients/year. In-hospital mortality rates decreased 61%, from 4.5% in 1988 to 1.8% in 2000. Reductions in the mortality rates were largest at high-volume centers (a 72% reduction in the relative mortality rate at largest-volume-quintile centers, compared with a 6% increase in the relative mortality rate at lowest-volume-quintile centers). The number of US hospitals where craniotomies were performed for meningiomas increased slightly. Fewer centers hosted one meningioma resection annually, whereas the largest centers had disproportionate increases in their caseloads, indicating a modest centralization of meningioma surgery in the US during this interval. CONCLUSIONS: The mortality and adverse hospital discharge disposition rates were lower when meningioma surgery was performed by high-volume providers. The annual US caseload increased, whereas the mortality rates decreased, especially at high-volume centers.  相似文献   
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OBJECTIVE: The purpose of this study was to determine the optimal time interval for identifying a pneumothorax (PTX) on chest radiograph (CXR) after placing a chest tube on water seal. METHODS: One hundred nineteen chest tubes were placed on water seal according to a prospective, observational study protocol. After water seal, both an early (3.1 +/- 2.1 hours) and a late (17.6 +/- 8.0 hours) CXR was obtained. RESULTS: Thirty-one patients had a PTX on follow-up CXRs. There were 22 early and 9 late PTXs identified. Three patients in the early group had a clinically significant PTX or an increase in the size of PTX on follow-up CXR. None of the patients in the late group had a clinically significant PTX (any worsening of their PTX) or required further intervention. CONCLUSION: A normal chest radiograph obtained 3 hours after placing a chest tube on water seal effectively excludes development of a clinically significant pneumothorax.  相似文献   
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