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11.
Intraductal papillary mucinous tumor (IPMT) of the pancreas is characterized by slow growth and a relatively favorable prognosis, however, invasive cancer originating in an IPMT is associated with a poor prognosis. Although various parameters in imaging modalities have been advocated to differentiate between benign IPMN and malignant ones, it is not easy to obtain definite diagnosis based on these parameters. Peroral pancreatoscopy (POPS) allows a clear and direct visualization of the pancreatic duct, providing useful information regarding tumor nature in IPMT. The authors have studied the usefulness of POPS in the diagnosis of IPMT. Nevertheless, its usefulness is not necessarily widely accepted and the significance of POPS is still controversial. In this review, the authors intended to address the diagnostic value of POPS and to clarify its role in the diagnosis of IPMT. The authors think treatment of IPMT can be improved by introducing POPS because the determination of surgical procedure as well as the area of resection based on the preoperative diagnosis of the involvement of the main pancreatic duct and branch duct is inevitable. 相似文献
12.
目的治疗顽固性下颌磨牙根尖周炎。并尽量减少对牙周膜的机械性损伤。方法采用下牙槽神经阻滞麻醉,并配合局部麻醉。拔牙钳的尖置放于釉牙骨质界以上,采用颊舌向摆动的方式将患牙拔下。在不断滴有生理盐水的条件下,立即用高速车针磨除患牙根尖2 ̄3mm的牙体组织,根管内3 ̄5mm深的充填物要用圆钻将其清除,再用牙胶尖和氢氧化钙糊剂充填。将患牙再植入牙槽窝之前,务必用生理盐水将牙槽窝冲洗干净,要求严格控制在15分钟内完成再植,并尽量减少对牙周膜的机械性损伤。再植牙齿一般不需要夹板固定,必要时可采用缝线缝合固定。结果我们选择的5例患者,术后随访1 ̄2年,1例患者再植失败,4例患者再植成功。结论特异性再植术治疗顽固性下颌磨牙根尖周炎疗效理想,而且较易掌握。 相似文献
13.
14.
Michiel R. de Boer Jos Twisk Annette C. Moll Hennie J. M. Völker-Dieben Henrica C. W. de Vet Ger H. M. B. van Rens 《Ophthalmic & physiological optics》2006,26(6):535-544
Consecutive patients (n = 215) who were referred to optometric (55%) or multidisciplinary (45%) low-vision services and above 50 years of age were recruited from four hospitals in the Netherlands. They completed two vision-related quality of life questionnaires, the Vision Quality of Life Core Measure (VCM1) and the Low Vision Quality of Life Questionnaire (LVQOL), before their first visit with low-vision services and 1 year later. At follow-up, patients referred to multidisciplinary low-vision services had lower scores on the mobility subscale of the LVQOL than patients referred to optometric low-vision services [5.3 points; 95% confidence interval (CI): 0.2-10.5]. Paired sample t-tests for the two groups of patients taken together show improvement for the VCM1 (3.1 points; 95% CI: 0.6-5.6) and deterioration for the basic aspects of vision (3.5 points; 95% CI: 1.1-5.9) and the mobility (6.6 points; 95% CI: 3.7-9.5) subscales of the LVQOL. In conclusion, people referred to optometric services showed less deterioration in mobility than those referred to multidisciplinary services. No differences were observed for any of the other subscales of the LVQOL and the VCM1. Future research in this field should include randomized controlled designs comparing low-vision services with no treatment or placebo. 相似文献
15.
This paper analyses the methodological issues inherent in evaluating healthcare education and considers approaches for addressing these.Recent policies have exhorted practitioners to base their practice on evidence; however in healthcare education the evidence base is not extensive. Whilst educational evaluation has advanced in the last decades, standardised designs and toolkits are not available. Each evaluation has different aims and occurs in specific contexts, thus the design has to fit the circumstances, yet meet the challenge of scientific credibility. Indicators of educational processes and outcomes are not scientifically verified; no toolkit of standardised ‘off-the-shelf’ valid, reliable and sensitive measures exists. The evidence base of educational practice is largely derived from small-scale, single case studies; the majority of measures are self-devised, unvalidated tools of unproven reliability, thus meta-synthesis is not appropriate and results are not generalisable. Healthcare educational evaluators need valid and reliable assessments of both knowledge acquisition and its application to practice. The need to establish and explain attribution, i.e. the relationship between educational inputs and outcomes is complex and requires experimental/quasi-experimental design. In addition, educational evaluators face the pragmatic challenge of practice in healthcare contexts, where confounding variables are hard to control and resources are scarce. 相似文献
16.
Jay Magaziner Eleanor M. Simonsick T. Michael Kashner J. Richard Hebel 《Journal of clinical epidemiology》1988,41(11)
The present study evaluates the response comparability between 361 elderly hip fracture patients admitted from the community to seven Baltimore area hospitals between 1984 and 1986 and interviewer selected proxies on items pertaining to patients' pre-fracture health and functional status. Agreement across items ranges from very poor to good and varies with respect to the health or functional area assessed. Proxies tend to overestimate patient disability relative to the patients themselves, especially with regard to capacity to perform instrumental activities of daily living. Although proxies who report the greatest contact with patients respond most comparably to the patients, when they do disagree, proxies with the greatest patient contact tend to overestimate patient disability. The authors suggest that attention to item construction and phrasing may improve response comparability. 相似文献
17.
18.
This report describes a model for identifying sets of teaching abilities considered to be effective for medical school teaching staff, based on roles teachers assume and functions they are expected to perform as instructors. The specification of these teaching abilities was the first step in the development of a comprehensive course on Medical Instruction at the Basic Institute of Medical and Agricultural Biology of the State University of Sao Paulo, Botucatu, Brazil, where the senior author is employed. The work was based on the assumption that medical school teachers are expected to assume a variety of teaching roles and that identification and specification of the abilities that define their roles can result in more effective and efficient teaching. 相似文献
19.
Galanin-like immunoreactivity has been visualized in nerve fibers in the islets of Langerhans, suggesting an involvement of
galanin in the neural regulation of islet function. In this study, we investigated the effects of galanin on basal and stimulated
insulin and glucagon secretion by infusing the peptide at three different dose rates in rats. We also studied the direct effect
of galanin on insulin secretion from freshly isolated rat islets. At 320 pmol/kg/min, but not at 20 or 80 pmol/kg/min, galanin
lowered basal plasma insulin levels. In contrast, basal plasma glucagon levels were lowered by galanin already at 20 and 80
pmol/kg/min. Furthermore, galanin inhibited both glucose- and arginine-induced insulin release at all three dose levels, whereas
arginine-induced glucagon release was not affected by galanin. Glucose-stimulated insulin secretion from isolated rat islets
was dose-dependently suppressed by galanin (10-6-10-8M). Therefore, it is concluded that galanin in rats inhibits insulin secretion, both in vivo and in vitro, and that at lower
dose levels, the peptide also inhibits basal glucagon release. 相似文献
20.
J. Saßmannshausen N. Bornfeld A. Kluge W. Sauerwein F. Härting A. Wessing 《International ophthalmology》1989,13(4):243-251
Advanced malignant melanomas of the uvea unsuited for an eye salvaging approach require enucleation of the tumor containing eye. A series of 68 patients is reported who underwent enucleation combined with insertion of a spherical dura-encased implant after 30 Gray pre-irridiation therapy of the orbit. Postoperative results with special attention to cosmetic outcome and motility of the prosthesis suggest that the insertion of an orbital implant should be preferred to the enucleation with no implant. 相似文献