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991.
Albert Kingman PhD 《Journal of public health dentistry》1992,52(6):353-360
Statistical issues associated with demonstrating significance between treatment groups (efficacy or superiority) and nonsignificance (equivalence) are presented and discussed. Methodologies for demonstrating efficacy of a product are proposed and contrasted, incorporating clinical and statistical criteria, with emphasis on situations in which placebo groups are precluded from the study design. Distinctions are drawn between study designs for demonstrating superiority and those for equivalence, including the determination of sample sizes needed for the different approaches. The "at least as good as" criterion is proposed as a reasonable alternative to that of equivalence in active control equivalence studies for demonstrating that dental product modifications or new products are efficacious. 相似文献
992.
Conway F. Saylor PhD Cynthia Cupit Swenson Ph.D. Paige Powell Ph.D. 《Child psychiatry and human development》1992,22(3):139-149
This article reports highlights from over 200 parents' observations of their preschoolers' play and verbalizations in the year following Hurricane Hugo. Commonly reported activities included reenactment and discussion of the event in multiple mediums, personification of Hugo, and expression of fears related to storms. Precocious concern for others, insight, and vocabulary were also noted. In these intact, relatively high functioning families, parents seemed able to facilitate their youngsters' adjustment without outside intervention.Portions of this report were presented in earlier form at the 1991 Society for Research in Child Development meeting in Seattle, Washington. 相似文献
993.
R. Langevin PhD P. Wright MA L. Handy 《Sexual abuse : a journal of research and treatment》1989,2(3):227-253
From a data bank of 479 sex offenders, a comparison was undertaken of those reporting any childhood sexual abuse versus those reporting none. A total of 201 men (42.0%) reported abuse, 261 (54.5%) did not and for 17 (3.5%), information was unavailable. The Abused and Nonabused Groups were compared on demographic information, the MMPI, Clarke Sex History Questionnaire and the Clarke Parent Child Relations Questionnaire. The Abused and Nonabused groups were similar in age, marital status, income, and criminal history, but the Abused Group had significantly less education. The Abused Group showed sexualization of their childhood, not only in the number of contacts with adults but also with age peers and siblings of both sexes. They tended to have wider ranging and more frequent sexual experiences as adults both with men and women. They more often raped. The Abused Group tended to show more emotional instability than the Nonabused Group in more frequent suicidal ideation and suicide attempts, as well as in elevated Mania Scale Scores on the MMPI. The family background of the Abused Group was more disturbed than the Nonabused Group's; especially father-son relations. They reported more alcohol use and abuse in their parents and more parent-child aggression than nonabused offenders did. Although it is unlikely that child sexual abuse causes sexual anomalies, the results of the present study suggest that childhood sexual victimization in the lives of adult sex offenders merits further investigation and has implications for treatment. 相似文献
994.
995.
Finite-element models of the human head 总被引:9,自引:0,他引:9
L. Voo PhD S. Kumaresan F. A. Pintar N. Yoganandan A. Sances Jr. 《Medical & biological engineering & computing》1996,34(5):375-381
A review is presented of the existing finite-element (FE) models for the biomechanics of human head injury. Finite element
analysis can be an important tool in describing the injury biomechanics of the human head. Complex geometric and material
properties pose challenges to FE modelling. Various assumptions and simplifications are made in model development that require
experimental validation. More recent models incorporate anatomic details with higher precision. The cervical vertebral column
and spinal cord are included. Model results have been more qualitative than quantitative owing to the lack of adequate experimental
validation. Advances include transient stress distribution in the brain tissue, frequency responses, effects of boundary conditions,
pressure release mechanism of the foramen magnum and the spinal cord, verification of rotation and cavitation theories of
brain injury, and protective effects of helmets. These theoretical results provide a basic understanding of the internal biomechanical
responses of the head under various dynamic loading conditions. Basic experimental research is still needed to determine more
accurate material properties and injury tolerance criteria, so that FE models can fully exercise their analytical and predictive
power for the study and prevention of human head injury. 相似文献
996.
Johannes W. G. Jacobs MD PhD Agnes van der Heide MD Johannes J. Rasker MD PhD Johannes W. J. Bijlsma MD PhD 《Patient education and counseling》1993,20(2-3):121-132
Chronic arthritis may have great impact on the patient but also on his or her family, relatives and friends. The assessment of the consequences of chronic arthritis and the effect of therapy not only in terms of physical, but also psychological and social dimensions deserves more attention. Functional ability and health status can be measured using a questionnaire or ‘instrument’, high-lighting important aspects not quantified with more traditional measurements. In this paper, arguments to apply such instruments more frequently are given. Health status instruments can be used not only to assess beneficial but also deleterious (side-)effects of therapeutic interventions. The properties are summarized of the most frequently used instruments assessing functional ability and health status. Many of these instruments have been evaluated sufficiently for validity and reliability; their sensitivity to detect change seems to be satisfactory. Therefore it is advisable to choose an internationally accepted, frequently used instrument, reflecting the area of interest. 相似文献
997.
998.
Ichiya Yamazaki MD PhD Norihisa Karube MD PhD Tamitaro Soma MD Yasuharu Noishiki MD PhD Yukio Ichikawa MD PhD 《Journal of artificial organs》2005,8(1):67-70
The aim of this study was to test the safety and efficacy of fragmented autologous adipose tissue (FAT) grafts for revascularization in aortoiliac occlusive disease. Twenty-seven patients with atherosclerotic aortoiliac occlusive disease underwent surgical treatment using FAT grafts. A piece of adipose connective tissue was obtained from the operative wound, cut into small pieces, and pressed into the wall of a fabric vascular prosthesis. Cumulative primary patency rates were 92% at 1 year, 92% at 3 years, and 86% at 6 years. Cumulative secondary patency rates were 96%, 96%, and 90% for the same intervals. In this clinical study, the FAT grafts demonstrated good long-term patency rates and no particular problems. This is the first clinical report of long-term outcomes using FAT grafts for aortofemoral or aortoiliac bypasses. FAT grafts are thus safe for revascularization in aortoiliac occlusive disease. 相似文献
999.
1000.
Benjamin B. Gelman MD PhD Dwayne A. Wolf MD PhD Juan Pablo Olano MD Lannette C. Linthicum MD 《Human pathology》1996,27(12):1282-1287
The Texas Department of Criminal Justice (TDCJ) houses many subjects with acquired immunodeficiency syndrome (AIDS) who receive medical care in a comprehensive AIDS treatment center. In this case-control autopsy survey, we compared pathological outcomes of TDCJ inmates treated at the center (n = 155) with nonincarcerated patients who died during the same period (n = 155). Using multiple regression analysis and a proportional hazards model, survival time in the prisoners was equivalent to that in the controls. With few exceptions, the prevalences of opportunistic viral, fungal, protozoal, and bacterial infections contributing to mortality were equivalent between groups. Mycobacterium tuberculosis was isolated more frequently in the inmates, and M avium intracellulare was isolated less frequently (P < .0001). The inmates had a higher prevalence of bacterial infection of the central nervous system (CNS) (9.1% v 1.4%; P < .006); half of all CNS bacterial infections were caused by M tuberculosis. Inmates had significantly lower prevalences of vacuolar myelopathy (P < .006) and severe wasting disease (P < .0009). We conclude that survival of prison inmates with AIDS treated in a comprehensive AIDS treatment center was equivalent to that of nonincarcerated subjects with AIDS. Prevalences of certain complications of AIDS differed in the inmates, showing that the prison environment influenced some of the underlying causes of AIDS morbidity and mortality. 相似文献