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21.
This paper examines the use of videotape simulation as a research method for the exploration of clinical problem-solving, the challenges posed and the strategies employed to overcome the difficulties encountered are discussed. The simulation forms part of a larger comparative study of outcomes of pre-registration nurse education programmes, commissioned by the English National Board for Nursing, Midwifery and Health Visiting.  相似文献   
22.
BACKGROUND AND PURPOSE: Odontoma is the most common odontogenic tumor. It includes 2 types, the compound and complex odontomas. There has not been a series study of the clinical and histologic features of odontomas from Taiwan. This study evaluated the clinicopathologic features of odontoma in Taiwanese. METHODS: Cases of odontoma treated from 1998 to 2002 identified from medical records were included. The microscopic features, radiographic features, and clinical history of the patients were reviewed and analyzed. RESULTS: A total of 81 odontomas in 81 patients (36 males and 45 females) were included. There were 62 compound and 19 complex odontomas. The mean age of the patients was 18 years with the majority of odontomas occurring in the first (32%) and second decade (38%) of life. Odontomas had a marked predilection for the maxilla (70%) and for the anterior region of the jaw (83%), particularly for the anterior maxilla (62%). Sixty four (79%) of the 81 odontomas were associated with 80 impacted teeth, including 71 permanent teeth, 2 deciduous teeth, and 7 supernumerary teeth. Of the 71 impacted permanent teeth, the maxillary central incisor (27%) was most commonly affected, followed by the maxillary canine (26%) and mandibular canine (24%). Histologic examination revealed enamel matrix in 90%, dentin in 100%, cementum in 88%, pulp tissue in 96%, fibrous capsule in 93%, ghost cells in 83%, reduced enamel epithelium in 86%, and nests of odontogenic epithelium in 58% of odontomas. Dentigerous cyst was associated with 9% of odontomas. CONCLUSIONS: In this series, odontomas occurred most often in the first and second decade of life. Although complex odontomas are usually found in the posterior jaw, in this Taiwanese series they were most commonly found in the anterior maxilla. Odontoma is frequently associated with an impacted tooth and occasionally with a dentigerous cyst. No recurrence of odontomas was found after surgical excision with follow-up of 1 to 15 years.  相似文献   
23.
The return of function following transection of the rat sciatic nerve has been assessed after repair by either standard microsurgical techniques (i.e., the use of microsutures to coapt the severed ends) or the new repair technique introduced by de Medinaceli and coworkers. The regeneration after transection was compared with that following sciatic nerve crush, i.e., a lesion in which the return of function is near optimal. Return of function was monitored serially using walking track analysis (i.e., the sciatic functional index, which indicates overall functional performance), the ability to spread the toes (which indicates intrinsic function in the foot), and the determination of muscle twitch tension of the middle digit. Function in the nerve crush group returned to within the normal range by 53 days, but function in the transection and repair groups did not return to normal before the rats were perfused at 85 postoperative days. However, the function regained when nerves were repaired with the de Medinaceli technique was significantly superior to that regained after repair with microsutures. Histological examination of the repair site (at 85 days) revealed that the regenerated nerve fibers in the de Medinaceli group crossed the site of anastomosis in a relatively orderly fashion, whereas they were more randomly arranged when microsutures were used. However, there was no statistical difference between the two groups in the number of regenerated fibers present in the distal stump. The increase in function in the de Medinaceli group may therefore arise primarily from an increase in the proportion of regenerating fibers which reach appropriate targets.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
24.
Deep brain stimulation of the subthalamic nucleus (STN-DBS) is an established therapy for Parkinson's disease (PD). A manic episode with psychotic symptoms induced by STN-DBS occurred in a previously psychiatrically healthy patient, focusing on the role of STN-DBS in influencing not only motor but also emotional behaviour.  相似文献   
25.
From the data submitted to the Pan American Health Organization (PAHO) by nationwide programs against sexually transmitted diseases (STD), HIV infection, and AIDS (2002), one can estimate the overall prevalence of syphilis among pregnant women to be 3.1% and to range from 1.00% in Peru to 6.21% in Paraguay. According to these data, the incidence of congenital syphilis ranges from 1.4 per 1000 live births in El Salvador to 12.0 per 1000 live births in Honduras. Among men who engage in sex with other men, who often classify themselves as heterosexual, as well as in female sex workers, the prevalence of syphilis ranged from 5% to 15%. Factors that determine the persistence of congenital syphilis as public health problem include a lack of awareness of the seriousness of the problem among politicians, health officials, and health care providers, difficult access to prenatal care, and screening services, a low demand for the test among users, and the stigma and discrimination that surround sexually transmitted diseases (STD). This paper seeks to focus the attention of health professionals on maternal and congenital syphilis so they will undertake actions, using an interprogrammatic approach, to eliminate congenital syphilis from Latin America and the Caribbean. Eliminating congenital syphilis will only become possible if interventions targeting vulnerable groups are also implemented. PAHO's role in eliminating congenital syphilis includes determining the baseline situation in the Region as a whole and in each country, developing communication and procurement strategies, supporting nationwide programs, promoting operational research, and facilitating interprogrammatic coordination.  相似文献   
26.
OBJECTIVE: To investigate the opinions of stakeholders (service commissioners and providers) on how performance data should be presented, in order to develop effective feedback methods to facilitate the use of these data in decision making. DESIGN: A qualitative analysis of semi-structured face-to-face and telephone interviews. League tables and fictional box plots were presented as an illustrative guide. The themes covered in the interviews were the effectiveness of these two feedback formats, their positive and negative characteristics, and ideas for new and improved feedback mechanisms. PARTICIPANTS: Thirty-six stakeholders representing a range of clinical and non-clinical roles within palliative care and the wider health care system across a variety of statutory and non-statutory organizations from London and the West Midlands. RESULTS: Box plots were received more positively than league tables, and qualitative information was considered more appropriate than pictorial feedback. Conventional methods such as league tables and box plots were judged to lack essential information on which important decisions could be based, such as additional contextual information and the methodological assumptions of the instrument. Both feedback methods were considered useful as an impetus to further discussion. There was a consensus that feedback should be constructive and able to be adapted to the organizational realities in which UK health services function. CONCLUSION: Qualitative research was viewed as the right evidence for gaining an understanding of the quality of end of life care. Stakeholders highlighted the importance of the lay perspective, which requires approaches that illuminate the subjective meanings of patient experience.  相似文献   
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Background  

Persisting neck pain is common in society. It has been reported that the prevalence of neck pain in office workers is much higher than in the general population. The costs to the worker, employer and society associated with work-related neck pain are known to be considerable and are escalating. The factors that place office workers at greater risk of developing neck pain are not understood. The aim of this study is to investigate the incidence and risk factors of work-related neck pain in Australian office workers.  相似文献   
30.
Nitric oxide (NO) is a free radical produced by several lung cells via the enzyme nitric oxide synthetase (NOS) and can be easily measured in exhaled air by chemiluminescence analysis. As the iso-enzyme iNOS may be induced by cytokines and endotoxin, NO is elevated in several chronic inflammatory airway diseases. Prior to using exhaled nitric oxide (eNO) as a non-invasive marker of airway inflammation in daily routine, the role of possibly influencing factors such as age, time of the day, smoking exposure and intra-individual variability have to be clarified. NO concentrations were measured in 107 healthy children aged 4–18 years at an expiratory flow of 184 ml/s. Spirometry and a skin-prick test were performed and a questionnaire on family history of atopy, personal symptoms of atopic disease and smoke exposure was completed. For intra-individual variability nitric oxide was measured in six children three times daily on 6 consecutive days. Median eNO concentration was 5.7 p.p.b., and increased significantly with age but did not vary with gender. No correlation was found between eNO and smoke exposure, positive skin-prick test, FEV 1, MEF25 and time of the day. There was no circadian rhythm found in the six children measured on 6 consecutive days, but the eNO showed an intra-individual coefficient of variation of 25.9%. With the help of a two-compartment model of the lung the alveolar NO concentration was estimated to be 4.1 p.p.b and was shown to be constant with age, whereas the airway part of NO steadily increased with age. When comparing eNO values with standardized measurement techniques, the age of the children and the large intra-subject coefficient of variation have to be taken into account, whereas in healthy children subject-specific factors such as atopic history, gender and skin test reactivity did not affect eNO measurement.  相似文献   
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