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21.
The World Wide Web creates new challenges and opportunities for medical educators. Prominent among these are the lack of consistent standards by which to evaluate web-based educational tools. We present the instrument that was used to review web-based innovations in medical education submissions to the 2003 Society of General Internal Medicine (SGIM) national meeting, and discuss the process used by the SGIM web-based clinical curriculum interest group to develop the instrument. The 5 highest-ranked submissions are summarized with commentary from the reviewers.  相似文献   
22.
Prof. Dr.  O. P. Steeno 《Andrologia》1989,21(2):103-112
Summary: For the quantitative determination of the testicular size or volume, two groups of apparatus are available: on the one hand, model testes, which are extremely valuable in longitudinal and cross-sectional studies during the period of pubescence, and on the other hand, measuring devices, with which the testicular dimensions can be specified. The latter instruments are helpful chiefly during the adolescent years and the diagnosis of problems surrounding fertility. The testicular volume can be calculated subsequently from the specific testicular measurements. The formula, for computing the volume of an ellipsoid, seems to be the most suitable for this purpose. Appliances also have been developed, which allow the largest (longitudinal) dimension (in mm) and the testicular volume (in cm3) to be read off simultaneously. A tonometer can be useful to quantitatively estimate the testicular consistency, which is a parameter of the testicular integrity at the level of tubular function (spermatozoa production).  相似文献   
23.
A randomized prospective study was undertaken to compare the electrical performances of three permanent, endocardial, tined pacing leads with different electrode designs--sintered platinum, vitreous carbon, and porous carbon. Ninety-nine patients received one of the leads (S80 31; 423S 32; S100 36). Acute R wave amplitude and ST elevation of the native endocardial electrogram, voltage threshold, impedance, and current flow at four pulse durations (0.25-1.0 msec) were measured. Voltage thresholds were measured noninvasively at each of four pulse durations at 2 days and 1, 3, and 6 months after implantation. No significant differences were found in sensing properties, or current flow at threshold at 0.5 msec pulse duration. The 423S lead had a significantly higher impedance at threshold and both a higher impedance and lower current flow at 5 V. No significant differences in threshold voltages were found between the three leads at any pulse duration, at any of the assessed times after implantation. Six-month thresholds for the S80, 423S, and S100 leads were 1.18 +/- 0.35, 1.17 +/- 0.29, and 1.06 +/- 0.38 V respectively at 0.5 msec pulse duration. Differences between 'high performance' pacing leads need to be of a greater order of magnitude before they can be exploited to give any real clinical advantage to patients.  相似文献   
24.
本文阐述了我院自行研制的气垫床工作模式转换器的结构、工作原理及应用效果。  相似文献   
25.
Fibre optic transillumination (FOTI) has been employed during the course of a 3-yr clinical dentifrice trial which initially involved 3003 children. At the initial examination, a subgroup of 813 13-yr-olds, and at the following annual visit, 2247 14-yr-olds, were examined using a 150 W lamp and 0.5 mm diameter probe. Routine clinical and radiographic examinations were performed separately. Compared to the clinical scores for anterior teeth, FOTI detected an additional 64% of interproximal lesions at the first visit while, for the larger number of children at the second visit, the increase in lesion detection level using FOTI was 37%. For the posterior teeth the comparable figure at the second examination was 92%. When FOTI data were compared to radiographic data for more than 52,000 posterior interproximal surfaces, FOTI could only detect 17% of radiographic Grade 2 lesions and 48% Grade 3 lesions. Thus any assumption that FOTI diagnoses may be a substitute for bitewing radiography appears premature.  相似文献   
26.
BACKGROUND: Diagnosis of atopic dermatitis (AD) depends on clinical features because no definitive diagnostic test exists. Criteria proposed by Hanifin and Rajka (Acta Derm Venereol (Stockh) 1980; Suppl 92: 44-47) were acceptable for hospital-based studies but were found not to be suitable for field studies. A UK working party formulated clinical diagnostic criteria that could be used in both hospital and epidemiological settings. Validation studies of the criteria showed widely variable results, probably due to different clinical settings and ethnicity. AIM AND OBJECTIVE: This study was undertaken to validate Hanifin and Rajka's criteria and to assess the comparative efficacy of their criteria and the UK working party's diagnostic criteria in the diagnosis of AD in a hospital setting in North India. SUBJECTS AND METHODS: This study serially included 101 patients with AD and 48 controls of paediatric age group. The study period was from July 2003 to December 2004. RESULTS: Hanifin and Rajka's criteria (sensitivity 96%, specificity 93.75%, positive predictive value 97% (PPV) and negative predictive value (NPV) 91.84%) had a statistical advantage over the UK working party's diagnostic criteria (sensitivity 86%, specificity 95.83%, PPV 97.75% and NPV 76.67%), with a P-value < 0.005.  相似文献   
27.
Background: Endoscopic mucosal resection (EMR) is widely accepted as a minimally invasive treatment for early gastric cancer (EGC) in Japan. However, the criteria for EMR must be strictly adhered to otherwise patients will miss the chance for additional therapy. We assess the important factor in expanding the indication of EMR. Methods: We investigated 1101 EGCs that had been resected by EMR at the National Cancer Center Hospital (NCCH), Tokyo, Japan, according to the indication recommended by Japanese Gastric Cancer Association (JGCA) and the expanded indication proposed by NCCH. Curability and local recurrence of the EMRs were assessed related to the applied indication and the number of resected specimens. Results: The recurrence rate of non‐evaluable resection was higher than that of evaluable resection (P < 0.0001). Eighty‐three lesions among 772 lesions in the JGCA group were non‐evaluable. Thirty‐seven leisons among 329 lesions in the NCCH group were non‐evaluable. There was no difference in the rate of non‐evaluable resection between JGCA and NCCH groups (P = 0.8329). However, the rate of curative resection was lower in the NCCH group than in the JGCA group (P = 0.0009). In piecemeal resection, there was no difference in the rate of non‐evaluable resection between JGCA and NCCH groups (P = 0.0527). In one‐piece resection, the rate of non‐evaluable resection was lower in the NCCH group than the JGCA group (P = 0.0137). Conclusion: Based on our series of cases, we propose one‐piece resection as a gold standard for EMR because it enables accurate histological evaluation, even in the EMR, according to the expanded indication.  相似文献   
28.
BACKGROUND: Based on good results in the treatment of superficial skin tumours, since the early 1990s topical photodynamic therapy with aminolaevulinic acid (ALA PDT) has been used for disseminated, inflammatory dermatoses including psoriasis. However, there is still a lack of well-documented trials. OBJECTIVE: A prospective randomized, double-blind phase I/II intrapatient comparison study was conducted in 12 patients to investigate whether topical ALA PDT is an effective treatment for chronic plaque-type psoriasis. METHODS: In each patient three psoriatic plaques were randomly treated with a light dose of 20 J/cm(2) and 0.1%, 1% and 5% ALA, respectively. Treatment was conducted twice a week until complete clearance or for a maximum of 12 irradiations. Therapeutic efficacy was assessed by weekly determination of the psoriasis severity index (PSI). RESULTS: The mean percentage improvement was 37.5%, 45.6% and 51.2% in the 0.1%, 1% and 5% ALA-treated groups, respectively. Irradiation had to be interrupted several times because of severe burning and pain sensation. CONCLUSION: Topical ALA PDT did not prove to be an appropriate treatment option for plaque-type psoriasis due to disappointing clinical efficacy, the time-consuming treatment procedure and its unfavourable adverse event profile.  相似文献   
29.
Systemic lupus erythematosus (SLE) is the archetypical immunologic disease. Approximately 20% of patients present in the first two decades of life. This article highlights some of the differences between pediatric and adult onset lupus.Children are defined as different from adults on the basis of age. Lupus presents with different gender ratios based on hormonal or pubertal status with more significant skewing toward female patients in the childbearing years. Female patients in the childbearing years appear to have a higher relative risk for mortality. Despite this, children have greater disease severity at onset based on the number of patients who present with significant organ inflammation, the amount of corticosteroids required and the abnormalities in lupus serologies including autoantibodies and low complements. Children present frequently with congenital and acquired complement defects. Children have an increased risk of infections that can be confused with lupus. They have a higher risk of serious pneumococcal infection and may have less protection from vaccinations received at the time of disease onset.The clinical immunology laboratory is critical in the diagnosis and treatment of pediatric SLE. The rapid analysis and transfer of laboratory results can be life saving for the child with suspected new onset lupus. The laboratory is also helpful in determining disease activity through analysis of immunologic trends over time in pediatric lupus patients. This is especially important in the noncompliant adolescent patient who has a correlation between disease activity and lupus serologic tests. Finally, the clinical immunology laboratory is an important tool for better understanding of the immunologic phenomena associated with lupus and of disease pathophysiology.  相似文献   
30.
The Student Training, Education and Practice for Dietetics (STEP‐DIET) CD‐ROM was developed at the University of Surrey to prepare dietetic students for the practical dietetic training component of their Nutrition/Dietetics degree. This study aimed to evaluate student response to the programme and its effectiveness as a teaching tool, based on the evaluation framework of D.L. Kirkpatrick (Evaluating a Course, 2nd edn. London, Kogan Page). Quantitative and qualitative methodologies were employed, with 41 dietetic students, separated by year group, completing questionnaires and taking part in six focus groups, at the University of Surrey. Student attitudes towards the instruction method and the STEP‐DIET programme itself were investigated, in conjunction with their perceived learning achievements. Students rated the programme highly in terms of design and content, however, there was a reluctance to accept computer‐assisted instruction (CAI) as a sole teaching method. A number of learning achievements relevant to dietetic practice were reported including a perceived increase in ability to conduct a dietetic interview and an increased understanding of the management of Type 2 diabetes. In general students reacted positively to the STEP‐DIET programme and it was perceived by students to be effective in preparing them for the practical component of their dietetic training.  相似文献   
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