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51.
The recent controversy surrounding the use of the reflex anal dilatation (RAD) sign in cases of suspected sexual abuse is a general illustration of the difficulties clinicians face in determining which symptoms, signs or laboratory tests to use in their daily practice. The evidence required fully to evaluate RAD is incomplete. The specificity in particular is uncertain. Sufficient evidence is, however, available to permit a quantitative examination of the test's performance under various circumstances. Our analysis suggests that, at the prevalence of anal abuse reported in one large series of children referred to paediatricians with suspected sexual abuse (13%), only if the specificity of the test is 99% or greater, may the positive predictive value of RAD be as high as 90%. At the likely prevalence of anal abuse in the general child population (less than 0.5%), however, an even higher specificity of 99.99% would be necessary to achieve a similar positive predictive value. 相似文献
52.
B Harvey 《Pediatrics》1991,87(1):1-6
Although the federal government has long had an interest in the health of children, action in support of this interest has been limited, fragmented, and inequitable. While health problems are increasing and becoming more complex and while policy leaders, business groups, and the public recognize that action is necessary, no response has been forthcoming. Development of a policy with measurable goals is needed. Resources must be allocated and data collected to periodically evaluate progress toward goals and to appropriately redirect resources. 相似文献
53.
54.
Infection continues to be a major complication of the use of indwelling venous catheters. In an attempt to avoid removal of the catheter and to minimize the systemic side-effects of antibiotics, the potential value of in-situ treatment of confirmed Broviac catheter infection was assessed in carefully selected patients attending an oncology unit. Fourteen episodes from 11 children were included in the study. A variety of organisms were encountered. Infective episodes were divided into two categories: (a) those occurring in patients with negative peripheral blood cultures and neutrophil count greater than 1.5 x 10(9) l-1 which were treated only by local instillation of heparinized antibiotic 8-hourly for 7-14 days (N = 8); (b) those occurring simultaneously with positive peripheral blood culture (or peripheral blood culture not performed) regardless of neutrophil count, or infection restricted to Broviac catheter but with a neutrophil count of less than 1.5 x 10(9) l-1; these were treated, with one exception, as above with the addition of systemic antibiotics (N = 6). Treatment was successful in 100% of infective episodes with negative cultures achieved between 5 and 12 days. Catheters remained in use a mean of 118 days following treatment of infection. This approach has obvious advantages but requires careful patient selection and monitoring. It prolongs the catheter life, obviates the need for systemic antibiotics for a local infection, and with appropriate instruction to parents and family practitioner, treatment may be administered on an outpatient basis. 相似文献
55.
This study investigated preferential encoding of threat material in subjects with posttraumatic stress disorder (PTSD) with a modified dot-probe paradigm. This paradigm indexes attentional bias by measuring response latency to name neutral target words that are presented adjacent to or distant from threat words. Motor vehicle accident survivors with PTSD (n = 15), subclinical PTSD (n = 15), and low anxiety (n = 15) were required to name target words that were presented either adjacent to or distant from strong threat, mild threat, positive, and neutral words. PTSD subjects named targets faster when they were in close proximity to mild threat words. Results suggested that PTSD subjects' attention was drawn to the mild threat stimuli and are discussed in the context of network models of PTSD. 相似文献
56.
57.
S S Altaie F A Meier R M Centor M Wakabongo D Toksoz K M Harvey E Basinger B A Johnson R R Brookman H P Dalton 《Diagnostic microbiology and infectious disease》1992,15(7):579-586
Two enzyme immunoassays (EIAs) detecting Chlamydia trachomatis from endocervical swabs, Syva MicroTrak (MT) and Abbott Chlamydiazyme (CZ), were compared with a tissue culture (TC) standard. Initially, 8% (100 of 1250) of specimens were TC positive, yielding sensitivities of 94% (94 of 100) for MT and 79% (79 of 100) for CZ with identical 98% specificities (1129 of 1150 for MT and 1130 of 1150 for CZ). Discrepant specimens were retested by both EIAs and assayed for elementary bodies (EBs) by a fluorescent antibody test. After discrepancy analysis, 9.5% (118) of 1240 patients were either TC or EB positive, yielding sensitivities of 94.1% for MT (111 of 118) and 79.7% for CZ (94 of 118) with identical specificities of 100% (1122 of 1122). These results indicate that the MT is significantly more sensitive (p less than 0.05, McNemar test) than CZ in detecting C. trachomatis from endocervical swabs. 相似文献
58.
S A Harvey P Ayabaca M Bucagu S Djibrina W N Edson S Gbangbade A McCaw-Binns B R Burkhalter 《International journal of gynaecology and obstetrics》2004,87(2):203-210
OBJECTIVES: Percentage of deliveries assisted by a skilled birth attendant (SBA) has become a proxy indicator for reducing maternal mortality in developing countries, but there is little data on SBA competence. Our objective was to evaluate the competence of health professionals who typically attend hospital and clinic-based births in Benin, Ecuador, Jamaica, and Rwanda. Methods: We measured competence against World Health Organization's (WHO) Integrated Management of Pregnancy and Childbirth guidelines. To evaluate knowledge, we used a 49-question multiple-choice test covering seven clinical areas. To evaluate skill, we had participants perform five different procedures on anatomical models. The 166 participants came from facilities at all levels of care in their respective countries. Results: On average, providers answered 55.8% of the knowledge questions correctly and performed 48.2% of the skills steps correctly. Scores differed somewhat by country, provider type, and subtopic. Conclusion: A wide gap exists between current evidence-based standards and current levels of provider competence. 相似文献
59.
Yuji Miyamoto Robert L. Kormos Harvey S. Borovetz Thomas Gaisor John M. Pristas John M. Armitage Robert L. Hardesty Bartley P. Griffith 《Artificial organs》1990,14(6):454-457
The interrelationships between hemodynamic variables including right ventricular (RV) performance with filling/ejection dynamics of the Novacor left ventricular assist system (LVAS) were determined in 10 of 11 patients who received LVAS as a bridge to heart transplant. Nine were successfully transplanted. Data were obtained intraoperatively, at periodic intervals up to 48 h postimplant and at explant. The hypotheses investigated included (a) RV performance influences LVAS filling characteristics and (b) LVAS pump output is influenced by systemic vascular resistance (SVR). During the period of LVAS support (2-126 days), pumping characteristics included a mean filling volume of 51 ml (range, 24-70), residual volume of 4.9 ml (range, 1-18), pump rate of 113/min (range, 63-175), and pump output of 5.81/min (range, 2.8-8.2). Multiple regression analysis identified pulmonary vascular resistance (PVR), RV stroke work index (RVSWI), and pulmonary capillary wedge pressure, but not RV ejection fraction, pulmonary artery pressure, or central venous pressure (CVP) as the most important correlates with LVAS filling volume (p less than 0.001, R2 = 0.6). In addition, LVAS pump output was influenced mainly by RVSWI, PVR, and SVR (p less than 0.001, R2 = 0.7). It was concluded that LVAS performance is highly dependent on RV function and systemic/pulmonary vascular resistances. 相似文献
60.
Extracorporeal shock wave lithotripsy is a new therapeutic technology that has received instant and widespread acceptance. The history and technical aspects of the procedure are presented, but most importantly, the authors discuss radiology's role and note the importance of management's awareness of the potential impact on departmental fiscal, equipment and personnel resources. 相似文献