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1.
Distance learning in a school nurse credential program.   总被引:4,自引:0,他引:4  
Distance learning, which encompasses many methodologies, is becoming a more readily available educational alternative. Because there are a limited number of school nurse credential programs and the demand for school nurses is increasing, distance learning may be a viable method of instruction. This article describes the authors' experiences organizing and presenting distance learning courses to five remote sites for students in a university school nurse credential program. After numerous inquiries, potential students from several areas were surveyed, and arrangements were made with universities in those areas to receive two-way audio and video transmissions of two seminar courses; later, two clinically oriented courses in the school nurse program. Students were able to complete their program requirements by taking equivalent course work at their local universities. Perceptions of students and the instructor, course evaluation, and practical suggestions are shared. Guidelines for potential students about selecting quality distance education programs are also noted.  相似文献   
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Posttransplant lymphoproliferative disorders (PTLDs) represent a morphologic, immunophenotypic, and genotypic spectrum of disease. Most recently, Knowles et al divided PTLDs into 3 distinct categories: (1) plasmacytic hyperplasia, (2) polymorphic B-cell hyperplasia and polymorphic B-cell lymphoma, and (3) immunoblastic lymphoma and multiple myeloma. Although one form of PTLD may progress to another form, only 1 previous case has been reported in which multiple myeloma developed 14 months after an original diagnosis of plasmacytic hyperplasia. The type of solid organ transplant was not specified in that case. We report a post--cardiac transplant plasmacytic hyperplasia developing 7 years posttransplant. Six years subsequent to the plasmacytic hyperplasia, the patient developed a posttransplant plasmacytic malignancy, supported by morphology, flow cytometric immunophenotyping, and genotypic studies. Since we have no data to support disseminated bony disease or an abnormal serum protein, we have not used the term "multiple myeloma" for this case.  相似文献   
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The purpose of this study was to characterize presenting imaging findings in women younger than 40 diagnosed with invasive breast cancer in the context of pathology and clinical course. Retrospective chart and imaging reviews were performed in patients under 40 diagnosed with breast cancer between July 1, 2004, and December 31, 2013. Patient demographic, imaging, pathology, and clinical data were collected. Overall and recurrence-free survival were estimated using the Kaplan-Meier method. Univariate Cox proportional hazards models were performed to identify factors associated with recurrence-free survival. Our study cohort consisted of 110 patients with invasive mammary carcinoma. One hundred one (91.8%) presented with a palpable mass. The mean size of all lesions on imaging was 3.5 cm ± 2.9 cm. Malignant calcifications were present in 54 (49.1%) cases. Imaging demonstrated multifocal or multicentric disease in 45 (40.9%) cases. Seventy four (67.3%) cancers were high grade. Luminal genomic subtypes were the most common (n = 61, 55.5%). At presentation, 4 (3.6%) patients had bilateral malignancy and 8 (7.3%) patients had distant metastatic disease. Ninety seven (88.2%) underwent neoadjuvant chemotherapy and 67 (60.9%) underwent radiation therapy. Seventy five (68.2%) of the patients underwent mastectomy. The restricted mean time to recurrence was 9.01 years (standard error 3.162 months). ER positivity was associated with compromised recurrence-free survival. The overall survival rate was 0.962 at 10 years. Young patients diagnosed with breast cancer typically present with advanced breast imaging findings and undergo aggressive treatment. Recurrence often occurs >5 years from diagnosis, and ER positive subtypes are at increased risk for recurrence.  相似文献   
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Quality control of leukocyte-reduced packed red cell units (LRprc) produced in blood facilities must conform to regulatory criteria, which state that units may not contain more than 1 x 10(6) to 5 x 10(6) white blood cells (WBC) per unit. The post-filtration WBC content of a total of n = 386 LRprc units was counted with a Nageotte chamber to model the probability that a unit would not meet the regulatory criteria. The distribution of the residual leukocyte counts is close to a negative binomial distribution (NBD) and is independent of the packed red cell volume filtered. The observed probability that a unit of blood has a residual WBC greater than 5 x 10(6) is 2.6 +/- 2.6 x 10(-3). A power analysis of the two-sample Kolmogorov-Smirnov (KS) test in this application shows that a sample size of 20 is sufficient for determining that the process is in control when an out of control process has a k NBD parameter greater than or equal to that of the in control process. The three out of control processes observed to date appear to have this property. A sample of size 80 may be necessary for confirming that process validation data sets conform to the larger 'reference' database (n = 386) for processes that are out of control in such a way that their k NBD parameter is less than the k parameter of the in control process.  相似文献   
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