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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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The purpose of this study was to develop a sensitive, rapid, and inexpensive immunofluorescence assay (IFA) using a recombinant porcine circovirus type 2 (PCV2) nucleocapsid protein for the serological detection of PCV2-specific antibodies in pig sera. The viral nucleocapsid protein encoded by the PCV2 ORF2 gene has recently been identified as the most immunoreactive viral protein that carries type-specific antigenic determinants. The ORF2 sequence of the IAF-2897 strain of PCV2 has been cloned into a pCEP5 eucaryotic expression vector under the control of the cytomegalovirus promoter, downstream of a polyhistidine sequence tag. The recombinant plasmid was used in transfection experiments with human epithelial kidney 293 cells that were further tested, and positive expression of the viral nucleocapsid protein was confirmed by IFA and Western blotting. Strong, specific fluorescence was observed in the nuclei of transfected cells. Test specificity to PCV2 was verified with several related infectious agents. Sensitivity was compared to that of standard IFA using PCV2-infected cells by evaluating the reactivities of 44 field serum samples from pigs on farms with a porcine population suffering from postweaning multisystemic wasting syndrome. The recombinant nucleocapsid-based test was able to detect 15 more positive-testing pigs than the PCV2-based IFA. Therefore, the relative sensitivity of the latter test was estimated at only 57.1% compared to that of the recombinant nucleocapsid-based test. The recombinant fusion protein has been purified by affinity chromatography and is being used to develop further sensitive serological tests.  相似文献   
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Fine-needle aspirations (FNAs) of parathyroid adenomas (PA) are infrequently encountered, but the scant literature on this topic emphasizes the difficulties in distinguishing them from thyroid neoplasms. We report on a case of an unsuspected intrathyroidal PA whose two FNA specimens mimicked almost perfectly the features of lymphocytic thyroiditis (LT). The smears from two FNAs of a "thyroid nodule" in a 22-yr-old woman were received with a clinical diagnosis of "LT." The cytological features of both specimens were similar and consisted of groups of epithelial cells in a background of numerous "naked" nuclei, interpreted as Hurthle cells and lymphocytes respectively, and leading to a cytological diagnosis of LT. Subsequent surgical excision of the "nodule" revealed a large intrathyroidal PA. The oxyphil cells and chief cells (the latter devoid of cytoplasm) present in the PA resembled Hurthle cells and lymphocytes respectively, in the FNA specimens. In conclusion, PA can give a cytological picture almost identical to that of LT in FNA material. Important clues to the diagnosis of PA in FNA specimens include the presence of prominent capillaries and the knowledge of a clinical history of hyperparathyroidism. Diagn. Cytopathol. 1999;21:276-279.  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   
6.
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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Elective laparoscopic management of sigmoid diverticulitis   总被引:6,自引:2,他引:4  
BACKGROUND: The aim of this study was to evaluate the results of elective laparoscopic treatment of sigmoid diverticulitis. METHODS: Between November 1991 and February 1998, 110 patients were treated by elective laparoscopic colectomy for sigmoid diverticulitis. The main data recorded were postoperation pain, return of bowel function, operation time, duration of hospital stay, and early and late complications. RESULTS: Mean age of patients was 63 years (range, 36-83 years). Nine patients (8.2%) required conversion to laparotomy because of severe adhesions, inflammatory process, or obesity. The mean operation time was 167 min. Return of bowel function was 2.3 days. Mean postoperation stay was 8.2 days. There was no perioperation death, and the morbidity rate was 7.3%, with two complications related to the laparoscopic approach (1 trocar site bowel incarceration and 1 small bowel fistula). Of the patients with complications, four (3.6%) needed reoperation. During the follow-up (6-79 months), no incisional hernia was observed. CONCLUSIONS: Laparoscopic colectomy for sigmoid diverticulitis is feasible and safe in more than 90% of cases. Benefits of the laparoscopic approach are the improved early postoperation course and the reduction of parietal sequelae.  相似文献   
9.
Exostoses of the external auditory canal can occur in patients living in coastal, southern California communities with a history of cold-water aquatic activities such as ocean surfing and swimming. Although most canal exostoses are asymptomatic, patients with canal obstruction greater than 80% can have recurrent episodes of external otitis and a related conductive hearing loss. In most cases, medical treatment resolves the symptomatic external otitis and related hearing loss. Patients recalcitrant to medical treatment are candidates for surgical removal of the exostoses. This report reviews the authors' surgical experience with 18 patients (27 ears) who have undergone surgical removal of exostoses. Their preferred surgical technique of transmeatal removal of exostoses with a specialized mallet and thin chisel under local anesthesia is described.  相似文献   
10.
During biological monitoring of exposure to a chemical, a possible source of interindividual variability in the measurement of a urinary metabolite that undergoes enterohepatic cycling is the presence of dietary fiber in the gastrointestinal tract. This study examined the effect of diets containing either the insoluble fiber Alphacel (nonnutritive bulk cellulose) or the soluble pectin (from citrus fruit, MW 20,000-40,000). Five groups of male Sprague-Dawley rats received one of the following diets: poor (5% w/w) or rich (15% w/w) in Alphacel, poor (5% w/w) or rich (15% w/w) in pectin, or no fiber (NF). Five micromol/kg of pyrene was administered by iv injection immediately after feeding the animals with their respective diet, and urine and feces collections started for the determination of 1-hydroxypyrene (1-OHP), a metabolite of pyrene. The type of fiber had no influence on the results. The rats receiving diets both poor and rich in fiber excreted less 1-OHP (18 +/- 8 and 15 +/- 7 pmol per g of rat, respectively) in the 24-h urine samples than the NF group (28 +/- 6 pmol/g). There was a nonstatistically significant trend towards increased fecal and total (urinary + fecal) 1-OHP excretion with increasing amount of fiber in the diet. An in vitro experiment showed an inverse correlation (r(2) = 0.98) between the amount of Alphacel in suspension in a 1-OHP aqueous solution and the recovery of 1-OHP from the soluble fraction. The reduction in urinary output of the metabolite due to fiber reaching approximately 40% may contribute to its interindividual variability observed in occupational and environmental studies.  相似文献   
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