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31.
In the classroom and in clinical areas, knowing how to learn, reason, reflect, think creatively, generate and evaluate ideas, make decisions, and solve problems have been identified as key elements of critical thinking. However, to be successful in the current health care arena, caregivers cannot be satisfied with possessing the ability to solve problems and simply meet preestablished "outcomes" (Alfaro-LeFevre, 1998). It is necessary to improve knowledge and practice applications and to explore the best ways to do things within a work group. This qualitative study evaluated the experiences of senior-level nursing students using case-based instruction in a course titled, Leading and Managing in Nursing. It is a replication and extension (Phase II) of an original case-based instruction study, completed with senior physical therapy students (Phase I). Phase III of this study trajectory is the creation of an interdisciplinary case-based course that addresses either or both clinical collaborative care issues or leadership and management issues for health care profession students. From this Phase II study, six thematic groupings emerged as distinct student experiences in case-based instruction-motivation, real world, learning, knowledge development, emerging from within, and group dynamic issues.  相似文献   
32.
3.男性:高催乳素血症通常导致阳痿、不孕和性功能低下.男性患者通常为大腺瘤,有神经系统症状.其原因可能是对症状认识的延误或者肿瘤生物学行为的差异.  相似文献   
33.
BACKGROUND AND OBJECTIVES: Freckles (ephelides) are small, light brown macules of sun-exposed areas in fair-skinned subjects. On the other hand, freckle-like pigmentation of the axilla is a highly characteristic feature of neurofibromatosis. To what extent (clinically and pathologically) are the two pigmentary defects similar? And to what extent are café-au-lait patches and freckle-like lesions similar pathologically? SUBJECTS AND METHODS: Ten cases of neurofibromatosis and 10 cases of freckles were examined clinically. Two biopsies were taken from the former; one obtained from an axillary freckle-like lesion, and the other from a café-au-lait patch. One biopsy only was taken from freckles. The biopsies were processed for haematoxylin and eosin, silver stain and transmission electron microscopy. RESULTS: Obvious differences were detected between freckles (ephelides) and freckle-like lesions in cases of neurofibromatosis. Café-au-lait patches and freckle-like lesions showed the same pathological changes of lentigo simplex, with increased melanin pigment from the basal layer up to the stratum corneum, moderate elongation of the rete ridges and mild inflammatory infiltrate intermingled with melanophages. Electron microscopy revealed an increase in melanocyte number and the presence of giant melanin granules in freckle-like pigmentation as well as café-au-lait patches. These ultrastructural freckles (ephelides) showed an increase in activity but not the number of melanocytes. CONCLUSIONS: The term freckle-like should be changed to lentiginous macules of neurofibromatosis. On the other hand, the café-au-lait patches should be considered as lentiginous patches. Freckles should be restricted to sun-exposed areas in fair-skinned persons only.  相似文献   
34.
目的:血液透析患者大多存在卡尼汀尤其是游离卡尼汀的缺乏,透析后补充左旋卡尼汀能够减轻、减少并发症及住院率。观察静脉补充左旋卡尼汀对肾移植前血液透析患者生活质量的影响。方法:选择2005-09/2006-09于柳州市人民医院进行维持性血液透析的患者30例,对治疗方案均知情同意。按随机数字表法分为左旋卡尼汀组和对照组,每组15例。每次透析结束后,左旋卡尼汀组静脉注射左旋卡尼汀20mg/kg,对照组注射等量的生理盐水,用药8周。用药前及用药8周时分别应用SF-36量表进行生活质量评分,由8个方面组成,每项都以0 ̄100分计,得分越高表示生活质量越好;同时记录透析相关症状及实验室参数,比较两组间差异。结果:30例患者全部进入结果分析。①与用药前相比,用药8周后左旋卡尼汀组SF-36总体评分增加了(18.29±12.71)分,对照组总评分减少了(6.40±16.39)分。与对照组相比,左旋卡尼汀组总评分及生理功能、总体健康、活力、社会功能、精神健康评分均显著增加(P<0.05 ̄0.01)。②与对照组相比,左旋卡尼汀组血红蛋白、白蛋白含量均显著增加(P<0.01)。结论:静脉补充左旋卡尼汀不仅有助于改善维持性血液透析患者的贫血状况,而且能明显提高其生活质量。  相似文献   
35.
36.
This study investigated the impact of immediate and delayed light activation on self-polymerization of a model dual-cured luting agent. The material presented the following components: base paste – 2,2-bis[4-(2-hydroxy-3-methacryloxyprop-1-oxy)phenyl]propane/triethylene glycol dimethacrylate (TEGDMA), camphorquinone, dimethyl-p-toluidine, butylated hydroxytoluene (BHT), glass fillers; catalyst paste – bisphenol-A ethoxylated dimethacrylate/TEGDMA, benzoyl peroxide, BHT, fillers. The pastes were mixed and seven polymerization scenarios tested: immediate light activation using low (5 J cm?2) or high (20 J cm?2) energy dose; delayed light activation (after 2 min – short delay) using low or high dose; delayed light activation (after 10 min – long delay) using low or high dose; and self-polymerization only. The degree of conversion (DC) and rate of polymerization (Rp) were evaluated for 30 min by real-time infrared spectroscopy. The lowest DC was detected for the self-polymerized and immediate–low dose groups, whereas the immediate–high dose and short delay–high dose groups showed the highest values. For the self-polymerized and immediate–high dose samples, Rpmax was detected after approximately 7 s, whereas this took approximately 14 s for the immediate–low dose group. Rpmax for the immediate–high dose group was higher than for the self-polymerized sample, which in turn was higher than for the immediate–low dose group. Rpmax for the short delay groups was higher than for the long delay groups. In conclusion, the extent of self-polymerization was influenced by the light dose reaching the material, which was dependent on high radiant exposure for optimal polymerization and the moment at which the light was applied; the short delay increased the DC for lower doses, while also generally decreasing the Rp for all scenarios.  相似文献   
37.
The aim of this study was to evaluate the fracture strength of teeth with different cavosurface margin cavity preparations and restored with composite resin and different adhesive systems. Eighty premolars were randomly divided in 8 groups, as follow: G1- sound teeth; G2- MOD preparation (no restoration); G3- Adper Single Bond without bevel preparation (butt joint); G4- Adper Single Bond with bevel preparation; G5- Adper Single Bond with chamfer preparation; G6- Clearfil SE Bond without bevel (butt joint); G7- Clearfil SE Bond with bevel preparation; G8- Clearfil SE Bond with chamfer preparation. The adhesive systems were applied according to manufacturers' instructions. Composite resin (Filtek Z250) was incrementally placed in all cavities. After 24 h, the specimens were tested in a universal testing machine at a crosshead speed of 0.5 mm/min. Data were analyzed statistically by ANOVA and Tukey's test (fracture strength) and Fisher's exact test (fracture pattern). The confidence level was set at 95% for all tests. Prepared and non-restored teeth showed the worst performance and G4 exhibited the highest fracture strength among all groups (p<0.05). In conclusion, all restorative treatments were able to recover the fracture strength of non-restored teeth to levels similar to those of sound teeth. Using a total-etch adhesive system with bevel preparation significantly improved the resistance to fracture.  相似文献   
38.
This in vitro study evaluated the effect of different apicoectomy angles, instruments used in root-end preparation, and dental materials used in retrofilling on apical sealing. Root ends were resected at 45 or 90 degrees in 80 single-rooted teeth. For each type of apicoectomy, root-end cavities were prepared with either a round carbide #2 bur or an S12/90D ultrasonic tip. The root-end cavities in each subgroup (apicoectomy + root-end preparation) were filled with silver amalgam without zinc (Am) or with gray mineral trioxide aggregate -Angelus (MTA), and the specimens were immediately immersed in 0.2% rhodamine B for 24 h. Sealing was evaluated based on the dyed cross-sectional dentin area. Data were analyzed statistically by the Kruskal-Wallis test at 5% significance level. No group showed complete sealing of root-end areas. The only significant factor affecting microleakage was dental material, with MTA exhibiting less leakage.  相似文献   
39.
Clinical Oral Investigations - To evaluate the validity of partial protocols (PP) to assess the prevalence of developmental defects of enamel (DDE) in permanent teeth and identify the strength of...  相似文献   
40.
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